Commit | Line | Data |
---|---|---|
60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001-2002 Intel Corp. | |
6 | * Copyright (c) 2002 Nokia Corp. | |
7 | * | |
60c778b2 | 8 | * This is part of the SCTP Linux Kernel Implementation. |
1da177e4 LT |
9 | * |
10 | * These are the state functions for the state machine. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * you can redistribute it and/or modify it under the terms of |
14 | * the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2, or (at your option) | |
16 | * any later version. | |
17 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
20 | * ************************ | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
22 | * See the GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
4b2f13a2 JK |
25 | * along with GNU CC; see the file COPYING. If not, see |
26 | * <http://www.gnu.org/licenses/>. | |
1da177e4 LT |
27 | * |
28 | * Please send any bug reports or fixes you make to the | |
29 | * email address(es): | |
91705c61 | 30 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 31 | * |
1da177e4 LT |
32 | * Written or modified by: |
33 | * La Monte H.P. Yarroll <piggy@acm.org> | |
34 | * Karl Knutson <karl@athena.chicago.il.us> | |
35 | * Mathew Kotowsky <kotowsky@sctp.org> | |
36 | * Sridhar Samudrala <samudrala@us.ibm.com> | |
37 | * Jon Grimm <jgrimm@us.ibm.com> | |
38 | * Hui Huang <hui.huang@nokia.com> | |
39 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
40 | * Daisy Chang <daisyc@us.ibm.com> | |
41 | * Ardelle Fan <ardelle.fan@intel.com> | |
42 | * Ryan Layer <rmlayer@us.ibm.com> | |
43 | * Kevin Gao <kevin.gao@intel.com> | |
1da177e4 LT |
44 | */ |
45 | ||
145ce502 JP |
46 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
47 | ||
1da177e4 LT |
48 | #include <linux/types.h> |
49 | #include <linux/kernel.h> | |
50 | #include <linux/ip.h> | |
51 | #include <linux/ipv6.h> | |
52 | #include <linux/net.h> | |
53 | #include <linux/inet.h> | |
5a0e3ad6 | 54 | #include <linux/slab.h> |
1da177e4 LT |
55 | #include <net/sock.h> |
56 | #include <net/inet_ecn.h> | |
57 | #include <linux/skbuff.h> | |
58 | #include <net/sctp/sctp.h> | |
59 | #include <net/sctp/sm.h> | |
60 | #include <net/sctp/structs.h> | |
61 | ||
103d750c MH |
62 | #define CREATE_TRACE_POINTS |
63 | #include <trace/events/sctp.h> | |
64 | ||
172a1599 XL |
65 | static struct sctp_packet *sctp_abort_pkt_new( |
66 | struct net *net, | |
67 | const struct sctp_endpoint *ep, | |
68 | const struct sctp_association *asoc, | |
69 | struct sctp_chunk *chunk, | |
70 | const void *payload, size_t paylen); | |
1da177e4 LT |
71 | static int sctp_eat_data(const struct sctp_association *asoc, |
72 | struct sctp_chunk *chunk, | |
a85bbeb2 | 73 | struct sctp_cmd_seq *commands); |
172a1599 XL |
74 | static struct sctp_packet *sctp_ootb_pkt_new( |
75 | struct net *net, | |
76 | const struct sctp_association *asoc, | |
77 | const struct sctp_chunk *chunk); | |
24cb81a6 EB |
78 | static void sctp_send_stale_cookie_err(struct net *net, |
79 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
80 | const struct sctp_association *asoc, |
81 | const struct sctp_chunk *chunk, | |
a85bbeb2 | 82 | struct sctp_cmd_seq *commands, |
1da177e4 | 83 | struct sctp_chunk *err_chunk); |
172a1599 XL |
84 | static enum sctp_disposition sctp_sf_do_5_2_6_stale( |
85 | struct net *net, | |
86 | const struct sctp_endpoint *ep, | |
87 | const struct sctp_association *asoc, | |
88 | const union sctp_subtype type, | |
89 | void *arg, | |
90 | struct sctp_cmd_seq *commands); | |
91 | static enum sctp_disposition sctp_sf_shut_8_4_5( | |
92 | struct net *net, | |
93 | const struct sctp_endpoint *ep, | |
94 | const struct sctp_association *asoc, | |
95 | const union sctp_subtype type, | |
96 | void *arg, | |
97 | struct sctp_cmd_seq *commands); | |
98 | static enum sctp_disposition sctp_sf_tabort_8_4_8( | |
99 | struct net *net, | |
24cb81a6 | 100 | const struct sctp_endpoint *ep, |
ece25dfa | 101 | const struct sctp_association *asoc, |
bfc6f827 | 102 | const union sctp_subtype type, |
ece25dfa | 103 | void *arg, |
a85bbeb2 | 104 | struct sctp_cmd_seq *commands); |
1da177e4 LT |
105 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk); |
106 | ||
172a1599 XL |
107 | static enum sctp_disposition sctp_stop_t1_and_abort( |
108 | struct net *net, | |
109 | struct sctp_cmd_seq *commands, | |
110 | __be16 error, int sk_err, | |
111 | const struct sctp_association *asoc, | |
112 | struct sctp_transport *transport); | |
52c1da39 | 113 | |
172a1599 XL |
114 | static enum sctp_disposition sctp_sf_abort_violation( |
115 | struct net *net, | |
116 | const struct sctp_endpoint *ep, | |
117 | const struct sctp_association *asoc, | |
118 | void *arg, | |
119 | struct sctp_cmd_seq *commands, | |
120 | const __u8 *payload, | |
121 | const size_t paylen); | |
aecedeab | 122 | |
172a1599 XL |
123 | static enum sctp_disposition sctp_sf_violation_chunklen( |
124 | struct net *net, | |
125 | const struct sctp_endpoint *ep, | |
126 | const struct sctp_association *asoc, | |
127 | const union sctp_subtype type, | |
128 | void *arg, | |
129 | struct sctp_cmd_seq *commands); | |
1da177e4 | 130 | |
172a1599 XL |
131 | static enum sctp_disposition sctp_sf_violation_paramlen( |
132 | struct net *net, | |
133 | const struct sctp_endpoint *ep, | |
134 | const struct sctp_association *asoc, | |
135 | const union sctp_subtype type, | |
136 | void *arg, void *ext, | |
137 | struct sctp_cmd_seq *commands); | |
6f4c618d | 138 | |
172a1599 XL |
139 | static enum sctp_disposition sctp_sf_violation_ctsn( |
140 | struct net *net, | |
141 | const struct sctp_endpoint *ep, | |
142 | const struct sctp_association *asoc, | |
143 | const union sctp_subtype type, | |
144 | void *arg, | |
145 | struct sctp_cmd_seq *commands); | |
aecedeab | 146 | |
172a1599 XL |
147 | static enum sctp_disposition sctp_sf_violation_chunk( |
148 | struct net *net, | |
149 | const struct sctp_endpoint *ep, | |
150 | const struct sctp_association *asoc, | |
151 | const union sctp_subtype type, | |
152 | void *arg, | |
153 | struct sctp_cmd_seq *commands); | |
ece25dfa | 154 | |
4785c7ae | 155 | static enum sctp_ierror sctp_sf_authenticate( |
172a1599 | 156 | const struct sctp_association *asoc, |
172a1599 | 157 | struct sctp_chunk *chunk); |
bbd0d598 | 158 | |
172a1599 XL |
159 | static enum sctp_disposition __sctp_sf_do_9_1_abort( |
160 | struct net *net, | |
24cb81a6 | 161 | const struct sctp_endpoint *ep, |
75205f47 | 162 | const struct sctp_association *asoc, |
bfc6f827 | 163 | const union sctp_subtype type, |
75205f47 | 164 | void *arg, |
a85bbeb2 | 165 | struct sctp_cmd_seq *commands); |
75205f47 | 166 | |
1da177e4 LT |
167 | /* Small helper function that checks if the chunk length |
168 | * is of the appropriate length. The 'required_length' argument | |
169 | * is set to be the size of a specific chunk we are testing. | |
509e7a31 MRL |
170 | * Return Values: true = Valid length |
171 | * false = Invalid length | |
1da177e4 LT |
172 | * |
173 | */ | |
172a1599 XL |
174 | static inline bool sctp_chunk_length_valid(struct sctp_chunk *chunk, |
175 | __u16 required_length) | |
1da177e4 LT |
176 | { |
177 | __u16 chunk_length = ntohs(chunk->chunk_hdr->length); | |
178 | ||
26b87c78 DB |
179 | /* Previously already marked? */ |
180 | if (unlikely(chunk->pdiscard)) | |
509e7a31 | 181 | return false; |
1da177e4 | 182 | if (unlikely(chunk_length < required_length)) |
509e7a31 | 183 | return false; |
1da177e4 | 184 | |
509e7a31 | 185 | return true; |
1da177e4 LT |
186 | } |
187 | ||
188 | /********************************************************** | |
189 | * These are the state functions for handling chunk events. | |
190 | **********************************************************/ | |
191 | ||
192 | /* | |
193 | * Process the final SHUTDOWN COMPLETE. | |
194 | * | |
195 | * Section: 4 (C) (diagram), 9.2 | |
196 | * Upon reception of the SHUTDOWN COMPLETE chunk the endpoint will verify | |
197 | * that it is in SHUTDOWN-ACK-SENT state, if it is not the chunk should be | |
198 | * discarded. If the endpoint is in the SHUTDOWN-ACK-SENT state the endpoint | |
199 | * should stop the T2-shutdown timer and remove all knowledge of the | |
200 | * association (and thus the association enters the CLOSED state). | |
201 | * | |
047a2428 | 202 | * Verification Tag: 8.5.1(C), sctpimpguide 2.41. |
1da177e4 LT |
203 | * C) Rules for packet carrying SHUTDOWN COMPLETE: |
204 | * ... | |
047a2428 JF |
205 | * - The receiver of a SHUTDOWN COMPLETE shall accept the packet |
206 | * if the Verification Tag field of the packet matches its own tag and | |
207 | * the T bit is not set | |
208 | * OR | |
209 | * it is set to its peer's tag and the T bit is set in the Chunk | |
210 | * Flags. | |
211 | * Otherwise, the receiver MUST silently discard the packet | |
212 | * and take no further action. An endpoint MUST ignore the | |
213 | * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state. | |
1da177e4 LT |
214 | * |
215 | * Inputs | |
216 | * (endpoint, asoc, chunk) | |
217 | * | |
218 | * Outputs | |
219 | * (asoc, reply_msg, msg_up, timers, counters) | |
220 | * | |
221 | * The return value is the disposition of the chunk. | |
222 | */ | |
172a1599 XL |
223 | enum sctp_disposition sctp_sf_do_4_C(struct net *net, |
224 | const struct sctp_endpoint *ep, | |
225 | const struct sctp_association *asoc, | |
226 | const union sctp_subtype type, | |
227 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 LT |
228 | { |
229 | struct sctp_chunk *chunk = arg; | |
230 | struct sctp_ulpevent *ev; | |
231 | ||
ece25dfa | 232 | if (!sctp_vtag_verify_either(chunk, asoc)) |
24cb81a6 | 233 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
ece25dfa | 234 | |
1da177e4 LT |
235 | /* RFC 2960 6.10 Bundling |
236 | * | |
237 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
238 | * SHUTDOWN COMPLETE with any other chunks. | |
239 | */ | |
240 | if (!chunk->singleton) | |
24cb81a6 | 241 | return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands); |
1da177e4 | 242 | |
ece25dfa | 243 | /* Make sure that the SHUTDOWN_COMPLETE chunk has a valid length. */ |
922dbc5b | 244 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 245 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 246 | commands); |
1da177e4 LT |
247 | |
248 | /* RFC 2960 10.2 SCTP-to-ULP | |
249 | * | |
250 | * H) SHUTDOWN COMPLETE notification | |
251 | * | |
252 | * When SCTP completes the shutdown procedures (section 9.2) this | |
253 | * notification is passed to the upper layer. | |
254 | */ | |
255 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 256 | 0, 0, 0, NULL, GFP_ATOMIC); |
df7deeb5 VY |
257 | if (ev) |
258 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
d808ad9a | 259 | SCTP_ULPEVENT(ev)); |
1da177e4 LT |
260 | |
261 | /* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint | |
262 | * will verify that it is in SHUTDOWN-ACK-SENT state, if it is | |
263 | * not the chunk should be discarded. If the endpoint is in | |
264 | * the SHUTDOWN-ACK-SENT state the endpoint should stop the | |
265 | * T2-shutdown timer and remove all knowledge of the | |
266 | * association (and thus the association enters the CLOSED | |
267 | * state). | |
268 | */ | |
269 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
270 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
271 | ||
272 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
273 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
274 | ||
275 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
276 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
277 | ||
b01a2407 EB |
278 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
279 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
280 | |
281 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
282 | ||
283 | return SCTP_DISPOSITION_DELETE_TCB; | |
1da177e4 LT |
284 | } |
285 | ||
286 | /* | |
287 | * Respond to a normal INIT chunk. | |
288 | * We are the side that is being asked for an association. | |
289 | * | |
290 | * Section: 5.1 Normal Establishment of an Association, B | |
291 | * B) "Z" shall respond immediately with an INIT ACK chunk. The | |
292 | * destination IP address of the INIT ACK MUST be set to the source | |
293 | * IP address of the INIT to which this INIT ACK is responding. In | |
294 | * the response, besides filling in other parameters, "Z" must set the | |
295 | * Verification Tag field to Tag_A, and also provide its own | |
296 | * Verification Tag (Tag_Z) in the Initiate Tag field. | |
297 | * | |
d808ad9a | 298 | * Verification Tag: Must be 0. |
1da177e4 LT |
299 | * |
300 | * Inputs | |
301 | * (endpoint, asoc, chunk) | |
302 | * | |
303 | * Outputs | |
304 | * (asoc, reply_msg, msg_up, timers, counters) | |
305 | * | |
306 | * The return value is the disposition of the chunk. | |
307 | */ | |
172a1599 XL |
308 | enum sctp_disposition sctp_sf_do_5_1B_init(struct net *net, |
309 | const struct sctp_endpoint *ep, | |
310 | const struct sctp_association *asoc, | |
311 | const union sctp_subtype type, | |
312 | void *arg, | |
313 | struct sctp_cmd_seq *commands) | |
1da177e4 | 314 | { |
62e6b7e4 XL |
315 | struct sctp_chunk *chunk = arg, *repl, *err_chunk; |
316 | struct sctp_unrecognized_param *unk_param; | |
1da177e4 | 317 | struct sctp_association *new_asoc; |
1da177e4 | 318 | struct sctp_packet *packet; |
1da177e4 LT |
319 | int len; |
320 | ||
2277c7cd RH |
321 | /* Update socket peer label if first association. */ |
322 | if (security_sctp_assoc_request((struct sctp_endpoint *)ep, | |
323 | chunk->skb)) | |
324 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
325 | ||
1da177e4 LT |
326 | /* 6.10 Bundling |
327 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
328 | * SHUTDOWN COMPLETE with any other chunks. | |
d808ad9a | 329 | * |
1da177e4 LT |
330 | * IG Section 2.11.2 |
331 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
332 | * enforce these rules by silently discarding an arriving packet | |
333 | * with an INIT chunk that is bundled with other chunks. | |
334 | */ | |
335 | if (!chunk->singleton) | |
24cb81a6 | 336 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
337 | |
338 | /* If the packet is an OOTB packet which is temporarily on the | |
339 | * control endpoint, respond with an ABORT. | |
340 | */ | |
2ce95503 | 341 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) { |
b01a2407 | 342 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
24cb81a6 | 343 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
8190f89d | 344 | } |
1da177e4 | 345 | |
1da177e4 | 346 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification |
d808ad9a | 347 | * Tag. |
1da177e4 LT |
348 | */ |
349 | if (chunk->sctp_hdr->vtag != 0) | |
24cb81a6 | 350 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
351 | |
352 | /* Make sure that the INIT chunk has a valid length. | |
353 | * Normally, this would cause an ABORT with a Protocol Violation | |
354 | * error, but since we don't have an association, we'll | |
355 | * just discard the packet. | |
356 | */ | |
01a992be | 357 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk))) |
24cb81a6 | 358 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 359 | |
bec9640b VY |
360 | /* If the INIT is coming toward a closing socket, we'll send back |
361 | * and ABORT. Essentially, this catches the race of INIT being | |
362 | * backloged to the socket at the same time as the user isses close(). | |
363 | * Since the socket and all its associations are going away, we | |
364 | * can treat this OOTB | |
365 | */ | |
366 | if (sctp_sstate(ep->base.sk, CLOSING)) | |
24cb81a6 | 367 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
bec9640b | 368 | |
1da177e4 LT |
369 | /* Verify the INIT chunk before processing it. */ |
370 | err_chunk = NULL; | |
b14878cc | 371 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
01a992be | 372 | (struct sctp_init_chunk *)chunk->chunk_hdr, chunk, |
1da177e4 LT |
373 | &err_chunk)) { |
374 | /* This chunk contains fatal error. It is to be discarded. | |
375 | * Send an ABORT, with causes if there is any. | |
376 | */ | |
377 | if (err_chunk) { | |
24cb81a6 | 378 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 | 379 | (__u8 *)(err_chunk->chunk_hdr) + |
922dbc5b | 380 | sizeof(struct sctp_chunkhdr), |
1da177e4 | 381 | ntohs(err_chunk->chunk_hdr->length) - |
922dbc5b | 382 | sizeof(struct sctp_chunkhdr)); |
1da177e4 LT |
383 | |
384 | sctp_chunk_free(err_chunk); | |
385 | ||
386 | if (packet) { | |
387 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
388 | SCTP_PACKET(packet)); | |
b01a2407 | 389 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
390 | return SCTP_DISPOSITION_CONSUME; |
391 | } else { | |
392 | return SCTP_DISPOSITION_NOMEM; | |
393 | } | |
394 | } else { | |
24cb81a6 | 395 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, |
1da177e4 LT |
396 | commands); |
397 | } | |
398 | } | |
399 | ||
d808ad9a | 400 | /* Grab the INIT header. */ |
4ae70c08 | 401 | chunk->subh.init_hdr = (struct sctp_inithdr *)chunk->skb->data; |
1da177e4 LT |
402 | |
403 | /* Tag the variable length parameters. */ | |
4ae70c08 | 404 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(struct sctp_inithdr)); |
1da177e4 LT |
405 | |
406 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
407 | if (!new_asoc) | |
408 | goto nomem; | |
409 | ||
409b95af VY |
410 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
411 | sctp_scope(sctp_source(chunk)), | |
412 | GFP_ATOMIC) < 0) | |
413 | goto nomem_init; | |
414 | ||
1da177e4 | 415 | /* The call, sctp_process_init(), can fail on memory allocation. */ |
de6becdc | 416 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), |
01a992be | 417 | (struct sctp_init_chunk *)chunk->chunk_hdr, |
1da177e4 LT |
418 | GFP_ATOMIC)) |
419 | goto nomem_init; | |
420 | ||
1da177e4 LT |
421 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ |
422 | ||
423 | /* If there are errors need to be reported for unknown parameters, | |
424 | * make sure to reserve enough room in the INIT ACK for them. | |
425 | */ | |
426 | len = 0; | |
427 | if (err_chunk) | |
428 | len = ntohs(err_chunk->chunk_hdr->length) - | |
922dbc5b | 429 | sizeof(struct sctp_chunkhdr); |
1da177e4 | 430 | |
1da177e4 LT |
431 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
432 | if (!repl) | |
df7deeb5 | 433 | goto nomem_init; |
1da177e4 LT |
434 | |
435 | /* If there are errors need to be reported for unknown parameters, | |
436 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
437 | * parameter. | |
438 | */ | |
439 | if (err_chunk) { | |
440 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
441 | * ERROR chunk generated by sctp_verify_init(). Since the | |
442 | * error cause code for "unknown parameter" and the | |
443 | * "Unrecognized parameter" type is the same, we can | |
444 | * construct the parameters in INIT ACK by copying the | |
445 | * ERROR causes over. | |
446 | */ | |
62e6b7e4 | 447 | unk_param = (struct sctp_unrecognized_param *) |
1da177e4 | 448 | ((__u8 *)(err_chunk->chunk_hdr) + |
922dbc5b | 449 | sizeof(struct sctp_chunkhdr)); |
1da177e4 LT |
450 | /* Replace the cause code with the "Unrecognized parameter" |
451 | * parameter type. | |
452 | */ | |
453 | sctp_addto_chunk(repl, len, unk_param); | |
454 | sctp_chunk_free(err_chunk); | |
455 | } | |
456 | ||
df7deeb5 VY |
457 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); |
458 | ||
1da177e4 LT |
459 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
460 | ||
461 | /* | |
462 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
463 | * "Z" MUST NOT allocate any resources, nor keep any states for the | |
464 | * new association. Otherwise, "Z" will be vulnerable to resource | |
465 | * attacks. | |
466 | */ | |
467 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
468 | ||
469 | return SCTP_DISPOSITION_DELETE_TCB; | |
470 | ||
1da177e4 LT |
471 | nomem_init: |
472 | sctp_association_free(new_asoc); | |
473 | nomem: | |
df7deeb5 VY |
474 | if (err_chunk) |
475 | sctp_chunk_free(err_chunk); | |
1da177e4 LT |
476 | return SCTP_DISPOSITION_NOMEM; |
477 | } | |
478 | ||
479 | /* | |
480 | * Respond to a normal INIT ACK chunk. | |
481 | * We are the side that is initiating the association. | |
482 | * | |
483 | * Section: 5.1 Normal Establishment of an Association, C | |
484 | * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init | |
485 | * timer and leave COOKIE-WAIT state. "A" shall then send the State | |
486 | * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start | |
487 | * the T1-cookie timer, and enter the COOKIE-ECHOED state. | |
488 | * | |
489 | * Note: The COOKIE ECHO chunk can be bundled with any pending outbound | |
490 | * DATA chunks, but it MUST be the first chunk in the packet and | |
491 | * until the COOKIE ACK is returned the sender MUST NOT send any | |
492 | * other packets to the peer. | |
493 | * | |
494 | * Verification Tag: 3.3.3 | |
495 | * If the value of the Initiate Tag in a received INIT ACK chunk is | |
496 | * found to be 0, the receiver MUST treat it as an error and close the | |
497 | * association by transmitting an ABORT. | |
498 | * | |
499 | * Inputs | |
500 | * (endpoint, asoc, chunk) | |
501 | * | |
502 | * Outputs | |
503 | * (asoc, reply_msg, msg_up, timers, counters) | |
504 | * | |
505 | * The return value is the disposition of the chunk. | |
506 | */ | |
172a1599 XL |
507 | enum sctp_disposition sctp_sf_do_5_1C_ack(struct net *net, |
508 | const struct sctp_endpoint *ep, | |
509 | const struct sctp_association *asoc, | |
510 | const union sctp_subtype type, | |
511 | void *arg, | |
512 | struct sctp_cmd_seq *commands) | |
1da177e4 | 513 | { |
01a992be | 514 | struct sctp_init_chunk *initchunk; |
172a1599 | 515 | struct sctp_chunk *chunk = arg; |
1da177e4 LT |
516 | struct sctp_chunk *err_chunk; |
517 | struct sctp_packet *packet; | |
1da177e4 LT |
518 | |
519 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 520 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 521 | |
1da177e4 LT |
522 | /* 6.10 Bundling |
523 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
524 | * SHUTDOWN COMPLETE with any other chunks. | |
525 | */ | |
526 | if (!chunk->singleton) | |
24cb81a6 | 527 | return sctp_sf_violation_chunk(net, ep, asoc, type, arg, commands); |
1da177e4 | 528 | |
ece25dfa | 529 | /* Make sure that the INIT-ACK chunk has a valid length */ |
cb1844c4 | 530 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_initack_chunk))) |
24cb81a6 | 531 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 532 | commands); |
1da177e4 | 533 | /* Grab the INIT header. */ |
4ae70c08 | 534 | chunk->subh.init_hdr = (struct sctp_inithdr *)chunk->skb->data; |
1da177e4 | 535 | |
1da177e4 LT |
536 | /* Verify the INIT chunk before processing it. */ |
537 | err_chunk = NULL; | |
b14878cc | 538 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
01a992be | 539 | (struct sctp_init_chunk *)chunk->chunk_hdr, chunk, |
1da177e4 LT |
540 | &err_chunk)) { |
541 | ||
2a493216 | 542 | enum sctp_error error = SCTP_ERROR_NO_RESOURCE; |
853f4b50 | 543 | |
1da177e4 | 544 | /* This chunk contains fatal error. It is to be discarded. |
d6701191 VY |
545 | * Send an ABORT, with causes. If there are no causes, |
546 | * then there wasn't enough memory. Just terminate | |
547 | * the association. | |
1da177e4 LT |
548 | */ |
549 | if (err_chunk) { | |
24cb81a6 | 550 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 | 551 | (__u8 *)(err_chunk->chunk_hdr) + |
922dbc5b | 552 | sizeof(struct sctp_chunkhdr), |
1da177e4 | 553 | ntohs(err_chunk->chunk_hdr->length) - |
922dbc5b | 554 | sizeof(struct sctp_chunkhdr)); |
1da177e4 LT |
555 | |
556 | sctp_chunk_free(err_chunk); | |
557 | ||
558 | if (packet) { | |
559 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
560 | SCTP_PACKET(packet)); | |
24cb81a6 | 561 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
8de8c873 | 562 | error = SCTP_ERROR_INV_PARAM; |
1da177e4 | 563 | } |
1da177e4 | 564 | } |
bbd0d598 VY |
565 | |
566 | /* SCTP-AUTH, Section 6.3: | |
567 | * It should be noted that if the receiver wants to tear | |
568 | * down an association in an authenticated way only, the | |
569 | * handling of malformed packets should not result in | |
570 | * tearing down the association. | |
571 | * | |
572 | * This means that if we only want to abort associations | |
573 | * in an authenticated way (i.e AUTH+ABORT), then we | |
25985edc | 574 | * can't destroy this association just because the packet |
bbd0d598 VY |
575 | * was malformed. |
576 | */ | |
577 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
24cb81a6 | 578 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
bbd0d598 | 579 | |
24cb81a6 EB |
580 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
581 | return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED, | |
8de8c873 | 582 | asoc, chunk->transport); |
1da177e4 LT |
583 | } |
584 | ||
585 | /* Tag the variable length parameters. Note that we never | |
586 | * convert the parameters in an INIT chunk. | |
587 | */ | |
4ae70c08 | 588 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(struct sctp_inithdr)); |
1da177e4 | 589 | |
01a992be | 590 | initchunk = (struct sctp_init_chunk *)chunk->chunk_hdr; |
1da177e4 LT |
591 | |
592 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT, | |
593 | SCTP_PEER_INIT(initchunk)); | |
594 | ||
3f7a87d2 FF |
595 | /* Reset init error count upon receipt of INIT-ACK. */ |
596 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); | |
597 | ||
1da177e4 LT |
598 | /* 5.1 C) "A" shall stop the T1-init timer and leave |
599 | * COOKIE-WAIT state. "A" shall then ... start the T1-cookie | |
600 | * timer, and enter the COOKIE-ECHOED state. | |
601 | */ | |
602 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
603 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
604 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
605 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
606 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
607 | SCTP_STATE(SCTP_STATE_COOKIE_ECHOED)); | |
608 | ||
730fc3d0 VY |
609 | /* SCTP-AUTH: genereate the assocition shared keys so that |
610 | * we can potentially signe the COOKIE-ECHO. | |
611 | */ | |
612 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_SHKEY, SCTP_NULL()); | |
613 | ||
1da177e4 LT |
614 | /* 5.1 C) "A" shall then send the State Cookie received in the |
615 | * INIT ACK chunk in a COOKIE ECHO chunk, ... | |
616 | */ | |
617 | /* If there is any errors to report, send the ERROR chunk generated | |
618 | * for unknown parameters as well. | |
619 | */ | |
620 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO, | |
621 | SCTP_CHUNK(err_chunk)); | |
622 | ||
623 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
624 | } |
625 | ||
59d8d443 XL |
626 | static bool sctp_auth_chunk_verify(struct net *net, struct sctp_chunk *chunk, |
627 | const struct sctp_association *asoc) | |
628 | { | |
629 | struct sctp_chunk auth; | |
630 | ||
631 | if (!chunk->auth_chunk) | |
632 | return true; | |
633 | ||
634 | /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo | |
635 | * is supposed to be authenticated and we have to do delayed | |
636 | * authentication. We've just recreated the association using | |
637 | * the information in the cookie and now it's much easier to | |
638 | * do the authentication. | |
639 | */ | |
640 | ||
641 | /* Make sure that we and the peer are AUTH capable */ | |
642 | if (!net->sctp.auth_enable || !asoc->peer.auth_capable) | |
643 | return false; | |
644 | ||
645 | /* set-up our fake chunk so that we can process it */ | |
646 | auth.skb = chunk->auth_chunk; | |
647 | auth.asoc = chunk->asoc; | |
648 | auth.sctp_hdr = chunk->sctp_hdr; | |
649 | auth.chunk_hdr = (struct sctp_chunkhdr *) | |
650 | skb_push(chunk->auth_chunk, | |
651 | sizeof(struct sctp_chunkhdr)); | |
652 | skb_pull(chunk->auth_chunk, sizeof(struct sctp_chunkhdr)); | |
653 | auth.transport = chunk->transport; | |
654 | ||
655 | return sctp_sf_authenticate(asoc, &auth) == SCTP_IERROR_NO_ERROR; | |
656 | } | |
657 | ||
1da177e4 LT |
658 | /* |
659 | * Respond to a normal COOKIE ECHO chunk. | |
660 | * We are the side that is being asked for an association. | |
661 | * | |
662 | * Section: 5.1 Normal Establishment of an Association, D | |
663 | * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply | |
664 | * with a COOKIE ACK chunk after building a TCB and moving to | |
665 | * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with | |
666 | * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK | |
667 | * chunk MUST be the first chunk in the packet. | |
668 | * | |
669 | * IMPLEMENTATION NOTE: An implementation may choose to send the | |
670 | * Communication Up notification to the SCTP user upon reception | |
671 | * of a valid COOKIE ECHO chunk. | |
672 | * | |
673 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
674 | * D) Rules for packet carrying a COOKIE ECHO | |
675 | * | |
676 | * - When sending a COOKIE ECHO, the endpoint MUST use the value of the | |
677 | * Initial Tag received in the INIT ACK. | |
678 | * | |
679 | * - The receiver of a COOKIE ECHO follows the procedures in Section 5. | |
680 | * | |
681 | * Inputs | |
682 | * (endpoint, asoc, chunk) | |
683 | * | |
684 | * Outputs | |
685 | * (asoc, reply_msg, msg_up, timers, counters) | |
686 | * | |
687 | * The return value is the disposition of the chunk. | |
688 | */ | |
172a1599 XL |
689 | enum sctp_disposition sctp_sf_do_5_1D_ce(struct net *net, |
690 | const struct sctp_endpoint *ep, | |
691 | const struct sctp_association *asoc, | |
692 | const union sctp_subtype type, | |
693 | void *arg, | |
694 | struct sctp_cmd_seq *commands) | |
1da177e4 | 695 | { |
30f6ebf6 | 696 | struct sctp_ulpevent *ev, *ai_ev = NULL, *auth_ev = NULL; |
1da177e4 | 697 | struct sctp_association *new_asoc; |
01a992be | 698 | struct sctp_init_chunk *peer_init; |
172a1599 | 699 | struct sctp_chunk *chunk = arg; |
1da177e4 | 700 | struct sctp_chunk *err_chk_p; |
172a1599 | 701 | struct sctp_chunk *repl; |
609ee467 | 702 | struct sock *sk; |
172a1599 | 703 | int error = 0; |
1da177e4 LT |
704 | |
705 | /* If the packet is an OOTB packet which is temporarily on the | |
706 | * control endpoint, respond with an ABORT. | |
707 | */ | |
2ce95503 | 708 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) { |
b01a2407 | 709 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
24cb81a6 | 710 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
8190f89d | 711 | } |
1da177e4 LT |
712 | |
713 | /* Make sure that the COOKIE_ECHO chunk has a valid length. | |
714 | * In this case, we check that we have enough for at least a | |
715 | * chunk header. More detailed verification is done | |
716 | * in sctp_unpack_cookie(). | |
717 | */ | |
922dbc5b | 718 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 719 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 720 | |
609ee467 VY |
721 | /* If the endpoint is not listening or if the number of associations |
722 | * on the TCP-style socket exceed the max backlog, respond with an | |
723 | * ABORT. | |
724 | */ | |
725 | sk = ep->base.sk; | |
726 | if (!sctp_sstate(sk, LISTENING) || | |
727 | (sctp_style(sk, TCP) && sk_acceptq_is_full(sk))) | |
24cb81a6 | 728 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
609ee467 | 729 | |
1da177e4 LT |
730 | /* "Decode" the chunk. We have no optional parameters so we |
731 | * are in good shape. | |
732 | */ | |
d808ad9a | 733 | chunk->subh.cookie_hdr = |
1da177e4 | 734 | (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 | 735 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
922dbc5b | 736 | sizeof(struct sctp_chunkhdr))) |
62b08083 | 737 | goto nomem; |
1da177e4 LT |
738 | |
739 | /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint | |
740 | * "Z" will reply with a COOKIE ACK chunk after building a TCB | |
741 | * and moving to the ESTABLISHED state. | |
742 | */ | |
743 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
744 | &err_chk_p); | |
745 | ||
746 | /* FIXME: | |
747 | * If the re-build failed, what is the proper error path | |
748 | * from here? | |
749 | * | |
750 | * [We should abort the association. --piggy] | |
751 | */ | |
752 | if (!new_asoc) { | |
753 | /* FIXME: Several errors are possible. A bad cookie should | |
754 | * be silently discarded, but think about logging it too. | |
755 | */ | |
756 | switch (error) { | |
757 | case -SCTP_IERROR_NOMEM: | |
758 | goto nomem; | |
759 | ||
760 | case -SCTP_IERROR_STALE_COOKIE: | |
24cb81a6 | 761 | sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands, |
1da177e4 | 762 | err_chk_p); |
24cb81a6 | 763 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
764 | |
765 | case -SCTP_IERROR_BAD_SIG: | |
766 | default: | |
24cb81a6 | 767 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
3ff50b79 | 768 | } |
1da177e4 LT |
769 | } |
770 | ||
1da177e4 | 771 | |
df7deeb5 VY |
772 | /* Delay state machine commands until later. |
773 | * | |
774 | * Re-build the bind address for the association is done in | |
1da177e4 LT |
775 | * the sctp_unpack_cookie() already. |
776 | */ | |
777 | /* This is a brand-new association, so these are not yet side | |
778 | * effects--it is safe to run them here. | |
779 | */ | |
780 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
781 | ||
de6becdc | 782 | if (!sctp_process_init(new_asoc, chunk, |
6a1e5f33 | 783 | &chunk->subh.cookie_hdr->c.peer_addr, |
1da177e4 LT |
784 | peer_init, GFP_ATOMIC)) |
785 | goto nomem_init; | |
786 | ||
730fc3d0 VY |
787 | /* SCTP-AUTH: Now that we've populate required fields in |
788 | * sctp_process_init, set up the assocaition shared keys as | |
789 | * necessary so that we can potentially authenticate the ACK | |
790 | */ | |
791 | error = sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC); | |
792 | if (error) | |
793 | goto nomem_init; | |
794 | ||
59d8d443 XL |
795 | if (!sctp_auth_chunk_verify(net, chunk, new_asoc)) { |
796 | sctp_association_free(new_asoc); | |
797 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
bbd0d598 VY |
798 | } |
799 | ||
1da177e4 LT |
800 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
801 | if (!repl) | |
df7deeb5 | 802 | goto nomem_init; |
1da177e4 LT |
803 | |
804 | /* RFC 2960 5.1 Normal Establishment of an Association | |
805 | * | |
806 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
807 | * send the Communication Up notification to the SCTP user | |
808 | * upon reception of a valid COOKIE ECHO chunk. | |
809 | */ | |
810 | ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0, | |
811 | new_asoc->c.sinit_num_ostreams, | |
812 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 813 | NULL, GFP_ATOMIC); |
1da177e4 LT |
814 | if (!ev) |
815 | goto nomem_ev; | |
816 | ||
d808ad9a | 817 | /* Sockets API Draft Section 5.3.1.6 |
0f3fffd8 | 818 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 819 | * delivers this notification to inform the application that of the |
0f3fffd8 | 820 | * peers requested adaptation layer. |
1da177e4 | 821 | */ |
0f3fffd8 ISJ |
822 | if (new_asoc->peer.adaptation_ind) { |
823 | ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc, | |
1da177e4 | 824 | GFP_ATOMIC); |
df7deeb5 VY |
825 | if (!ai_ev) |
826 | goto nomem_aiev; | |
827 | } | |
828 | ||
30f6ebf6 XL |
829 | if (!new_asoc->peer.auth_capable) { |
830 | auth_ev = sctp_ulpevent_make_authkey(new_asoc, 0, | |
831 | SCTP_AUTH_NO_AUTH, | |
832 | GFP_ATOMIC); | |
833 | if (!auth_ev) | |
834 | goto nomem_authev; | |
835 | } | |
836 | ||
df7deeb5 VY |
837 | /* Add all the state machine commands now since we've created |
838 | * everything. This way we don't introduce memory corruptions | |
839 | * during side-effect processing and correclty count established | |
840 | * associations. | |
841 | */ | |
842 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
843 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
844 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
b01a2407 EB |
845 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
846 | SCTP_INC_STATS(net, SCTP_MIB_PASSIVEESTABS); | |
df7deeb5 VY |
847 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
848 | ||
9f70f46b | 849 | if (new_asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
df7deeb5 VY |
850 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, |
851 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
852 | ||
df7deeb5 VY |
853 | /* This will send the COOKIE ACK */ |
854 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
855 | ||
856 | /* Queue the ASSOC_CHANGE event */ | |
857 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
858 | ||
859 | /* Send up the Adaptation Layer Indication event */ | |
860 | if (ai_ev) | |
1da177e4 | 861 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
df7deeb5 | 862 | SCTP_ULPEVENT(ai_ev)); |
1da177e4 | 863 | |
30f6ebf6 XL |
864 | if (auth_ev) |
865 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
866 | SCTP_ULPEVENT(auth_ev)); | |
867 | ||
1da177e4 LT |
868 | return SCTP_DISPOSITION_CONSUME; |
869 | ||
30f6ebf6 XL |
870 | nomem_authev: |
871 | sctp_ulpevent_free(ai_ev); | |
df7deeb5 VY |
872 | nomem_aiev: |
873 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
874 | nomem_ev: |
875 | sctp_chunk_free(repl); | |
1da177e4 LT |
876 | nomem_init: |
877 | sctp_association_free(new_asoc); | |
878 | nomem: | |
879 | return SCTP_DISPOSITION_NOMEM; | |
880 | } | |
881 | ||
882 | /* | |
883 | * Respond to a normal COOKIE ACK chunk. | |
b52effd2 | 884 | * We are the side that is asking for an association. |
1da177e4 LT |
885 | * |
886 | * RFC 2960 5.1 Normal Establishment of an Association | |
887 | * | |
888 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the | |
889 | * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie | |
890 | * timer. It may also notify its ULP about the successful | |
891 | * establishment of the association with a Communication Up | |
892 | * notification (see Section 10). | |
893 | * | |
894 | * Verification Tag: | |
895 | * Inputs | |
896 | * (endpoint, asoc, chunk) | |
897 | * | |
898 | * Outputs | |
899 | * (asoc, reply_msg, msg_up, timers, counters) | |
900 | * | |
901 | * The return value is the disposition of the chunk. | |
902 | */ | |
172a1599 XL |
903 | enum sctp_disposition sctp_sf_do_5_1E_ca(struct net *net, |
904 | const struct sctp_endpoint *ep, | |
905 | const struct sctp_association *asoc, | |
906 | const union sctp_subtype type, | |
907 | void *arg, | |
908 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
909 | { |
910 | struct sctp_chunk *chunk = arg; | |
911 | struct sctp_ulpevent *ev; | |
912 | ||
913 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 914 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
915 | |
916 | /* Verify that the chunk length for the COOKIE-ACK is OK. | |
917 | * If we don't do this, any bundled chunks may be junked. | |
918 | */ | |
922dbc5b | 919 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 920 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
921 | commands); |
922 | ||
923 | /* Reset init error count upon receipt of COOKIE-ACK, | |
924 | * to avoid problems with the managemement of this | |
925 | * counter in stale cookie situations when a transition back | |
926 | * from the COOKIE-ECHOED state to the COOKIE-WAIT | |
927 | * state is performed. | |
928 | */ | |
3f7a87d2 | 929 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); |
1da177e4 | 930 | |
2277c7cd RH |
931 | /* Set peer label for connection. */ |
932 | security_inet_conn_established(ep->base.sk, chunk->skb); | |
933 | ||
1da177e4 LT |
934 | /* RFC 2960 5.1 Normal Establishment of an Association |
935 | * | |
936 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move | |
937 | * from the COOKIE-ECHOED state to the ESTABLISHED state, | |
938 | * stopping the T1-cookie timer. | |
939 | */ | |
940 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
941 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
942 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
943 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
b01a2407 EB |
944 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
945 | SCTP_INC_STATS(net, SCTP_MIB_ACTIVEESTABS); | |
1da177e4 | 946 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
9f70f46b | 947 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
948 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, |
949 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
1da177e4 LT |
950 | |
951 | /* It may also notify its ULP about the successful | |
952 | * establishment of the association with a Communication Up | |
953 | * notification (see Section 10). | |
954 | */ | |
955 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, | |
956 | 0, asoc->c.sinit_num_ostreams, | |
957 | asoc->c.sinit_max_instreams, | |
a5a35e76 | 958 | NULL, GFP_ATOMIC); |
1da177e4 LT |
959 | |
960 | if (!ev) | |
961 | goto nomem; | |
962 | ||
963 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
964 | ||
965 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 966 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 967 | * delivers this notification to inform the application that of the |
0f3fffd8 | 968 | * peers requested adaptation layer. |
1da177e4 | 969 | */ |
0f3fffd8 ISJ |
970 | if (asoc->peer.adaptation_ind) { |
971 | ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); | |
1da177e4 LT |
972 | if (!ev) |
973 | goto nomem; | |
974 | ||
975 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
976 | SCTP_ULPEVENT(ev)); | |
977 | } | |
978 | ||
30f6ebf6 XL |
979 | if (!asoc->peer.auth_capable) { |
980 | ev = sctp_ulpevent_make_authkey(asoc, 0, SCTP_AUTH_NO_AUTH, | |
981 | GFP_ATOMIC); | |
982 | if (!ev) | |
983 | goto nomem; | |
984 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
985 | SCTP_ULPEVENT(ev)); | |
986 | } | |
987 | ||
1da177e4 LT |
988 | return SCTP_DISPOSITION_CONSUME; |
989 | nomem: | |
990 | return SCTP_DISPOSITION_NOMEM; | |
991 | } | |
992 | ||
993 | /* Generate and sendout a heartbeat packet. */ | |
172a1599 XL |
994 | static enum sctp_disposition sctp_sf_heartbeat( |
995 | const struct sctp_endpoint *ep, | |
996 | const struct sctp_association *asoc, | |
997 | const union sctp_subtype type, | |
998 | void *arg, | |
999 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
1000 | { |
1001 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
1002 | struct sctp_chunk *reply; | |
1da177e4 LT |
1003 | |
1004 | /* Send a heartbeat to our peer. */ | |
92c73af5 | 1005 | reply = sctp_make_heartbeat(asoc, transport); |
1da177e4 LT |
1006 | if (!reply) |
1007 | return SCTP_DISPOSITION_NOMEM; | |
1008 | ||
1009 | /* Set rto_pending indicating that an RTT measurement | |
1010 | * is started with this heartbeat chunk. | |
1011 | */ | |
1012 | sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING, | |
1013 | SCTP_TRANSPORT(transport)); | |
1014 | ||
1015 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
1016 | return SCTP_DISPOSITION_CONSUME; | |
1017 | } | |
1018 | ||
1019 | /* Generate a HEARTBEAT packet on the given transport. */ | |
172a1599 XL |
1020 | enum sctp_disposition sctp_sf_sendbeat_8_3(struct net *net, |
1021 | const struct sctp_endpoint *ep, | |
1022 | const struct sctp_association *asoc, | |
1023 | const union sctp_subtype type, | |
1024 | void *arg, | |
1025 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
1026 | { |
1027 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
1028 | ||
b9f84786 | 1029 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
1030 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
1031 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
1032 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
1033 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 1034 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
1035 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
1036 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
1037 | return SCTP_DISPOSITION_DELETE_TCB; |
1038 | } | |
1039 | ||
1040 | /* Section 3.3.5. | |
1041 | * The Sender-specific Heartbeat Info field should normally include | |
1042 | * information about the sender's current time when this HEARTBEAT | |
1043 | * chunk is sent and the destination transport address to which this | |
1044 | * HEARTBEAT is sent (see Section 8.3). | |
1045 | */ | |
1046 | ||
52ccb8e9 | 1047 | if (transport->param_flags & SPP_HB_ENABLE) { |
1da177e4 LT |
1048 | if (SCTP_DISPOSITION_NOMEM == |
1049 | sctp_sf_heartbeat(ep, asoc, type, arg, | |
1050 | commands)) | |
1051 | return SCTP_DISPOSITION_NOMEM; | |
245cba7e | 1052 | |
1da177e4 LT |
1053 | /* Set transport error counter and association error counter |
1054 | * when sending heartbeat. | |
1055 | */ | |
7e99013a | 1056 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
1da177e4 LT |
1057 | SCTP_TRANSPORT(transport)); |
1058 | } | |
245cba7e VY |
1059 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_IDLE, |
1060 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
1061 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE, |
1062 | SCTP_TRANSPORT(transport)); | |
1063 | ||
d808ad9a | 1064 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
1065 | } |
1066 | ||
7b9438de | 1067 | /* resend asoc strreset_chunk. */ |
172a1599 XL |
1068 | enum sctp_disposition sctp_sf_send_reconf(struct net *net, |
1069 | const struct sctp_endpoint *ep, | |
1070 | const struct sctp_association *asoc, | |
1071 | const union sctp_subtype type, | |
1072 | void *arg, | |
1073 | struct sctp_cmd_seq *commands) | |
7b9438de XL |
1074 | { |
1075 | struct sctp_transport *transport = arg; | |
1076 | ||
1077 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
1078 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
1079 | SCTP_ERROR(ETIMEDOUT)); | |
1080 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ | |
1081 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
1082 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); | |
1083 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); | |
1084 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1085 | return SCTP_DISPOSITION_DELETE_TCB; | |
1086 | } | |
1087 | ||
1088 | sctp_chunk_hold(asoc->strreset_chunk); | |
1089 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1090 | SCTP_CHUNK(asoc->strreset_chunk)); | |
1091 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
1092 | ||
1093 | return SCTP_DISPOSITION_CONSUME; | |
1094 | } | |
1095 | ||
1da177e4 LT |
1096 | /* |
1097 | * Process an heartbeat request. | |
1098 | * | |
1099 | * Section: 8.3 Path Heartbeat | |
1100 | * The receiver of the HEARTBEAT should immediately respond with a | |
1101 | * HEARTBEAT ACK that contains the Heartbeat Information field copied | |
1102 | * from the received HEARTBEAT chunk. | |
1103 | * | |
1104 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1105 | * When receiving an SCTP packet, the endpoint MUST ensure that the | |
1106 | * value in the Verification Tag field of the received SCTP packet | |
1107 | * matches its own Tag. If the received Verification Tag value does not | |
1108 | * match the receiver's own tag value, the receiver shall silently | |
1109 | * discard the packet and shall not process it any further except for | |
1110 | * those cases listed in Section 8.5.1 below. | |
1111 | * | |
1112 | * Inputs | |
1113 | * (endpoint, asoc, chunk) | |
1114 | * | |
1115 | * Outputs | |
1116 | * (asoc, reply_msg, msg_up, timers, counters) | |
1117 | * | |
1118 | * The return value is the disposition of the chunk. | |
1119 | */ | |
172a1599 XL |
1120 | enum sctp_disposition sctp_sf_beat_8_3(struct net *net, |
1121 | const struct sctp_endpoint *ep, | |
1122 | const struct sctp_association *asoc, | |
1123 | const union sctp_subtype type, | |
1124 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 | 1125 | { |
3c918704 | 1126 | struct sctp_paramhdr *param_hdr; |
1da177e4 LT |
1127 | struct sctp_chunk *chunk = arg; |
1128 | struct sctp_chunk *reply; | |
1129 | size_t paylen = 0; | |
1130 | ||
1131 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 1132 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1133 | |
1134 | /* Make sure that the HEARTBEAT chunk has a valid length. */ | |
38c00f74 XL |
1135 | if (!sctp_chunk_length_valid(chunk, |
1136 | sizeof(struct sctp_heartbeat_chunk))) | |
24cb81a6 | 1137 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1138 | commands); |
1139 | ||
1140 | /* 8.3 The receiver of the HEARTBEAT should immediately | |
1141 | * respond with a HEARTBEAT ACK that contains the Heartbeat | |
1142 | * Information field copied from the received HEARTBEAT chunk. | |
1143 | */ | |
4d2dcdf4 | 1144 | chunk->subh.hb_hdr = (struct sctp_heartbeathdr *)chunk->skb->data; |
3c918704 | 1145 | param_hdr = (struct sctp_paramhdr *)chunk->subh.hb_hdr; |
922dbc5b | 1146 | paylen = ntohs(chunk->chunk_hdr->length) - sizeof(struct sctp_chunkhdr); |
06a31e2b TG |
1147 | |
1148 | if (ntohs(param_hdr->length) > paylen) | |
1149 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, | |
1150 | param_hdr, commands); | |
1151 | ||
62b08083 SS |
1152 | if (!pskb_pull(chunk->skb, paylen)) |
1153 | goto nomem; | |
1da177e4 | 1154 | |
06a31e2b | 1155 | reply = sctp_make_heartbeat_ack(asoc, chunk, param_hdr, paylen); |
1da177e4 LT |
1156 | if (!reply) |
1157 | goto nomem; | |
1158 | ||
1159 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
1160 | return SCTP_DISPOSITION_CONSUME; | |
1161 | ||
1162 | nomem: | |
1163 | return SCTP_DISPOSITION_NOMEM; | |
1164 | } | |
1165 | ||
1166 | /* | |
1167 | * Process the returning HEARTBEAT ACK. | |
1168 | * | |
1169 | * Section: 8.3 Path Heartbeat | |
1170 | * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT | |
1171 | * should clear the error counter of the destination transport | |
1172 | * address to which the HEARTBEAT was sent, and mark the destination | |
1173 | * transport address as active if it is not so marked. The endpoint may | |
1174 | * optionally report to the upper layer when an inactive destination | |
1175 | * address is marked as active due to the reception of the latest | |
1176 | * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also | |
1177 | * clear the association overall error count as well (as defined | |
1178 | * in section 8.1). | |
1179 | * | |
1180 | * The receiver of the HEARTBEAT ACK should also perform an RTT | |
1181 | * measurement for that destination transport address using the time | |
1182 | * value carried in the HEARTBEAT ACK chunk. | |
1183 | * | |
1184 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1185 | * | |
1186 | * Inputs | |
1187 | * (endpoint, asoc, chunk) | |
1188 | * | |
1189 | * Outputs | |
1190 | * (asoc, reply_msg, msg_up, timers, counters) | |
1191 | * | |
1192 | * The return value is the disposition of the chunk. | |
1193 | */ | |
172a1599 XL |
1194 | enum sctp_disposition sctp_sf_backbeat_8_3(struct net *net, |
1195 | const struct sctp_endpoint *ep, | |
1196 | const struct sctp_association *asoc, | |
1197 | const union sctp_subtype type, | |
1198 | void *arg, | |
1199 | struct sctp_cmd_seq *commands) | |
1da177e4 | 1200 | { |
edf903f8 | 1201 | struct sctp_sender_hb_info *hbinfo; |
1da177e4 | 1202 | struct sctp_chunk *chunk = arg; |
1da177e4 | 1203 | struct sctp_transport *link; |
1da177e4 | 1204 | unsigned long max_interval; |
edf903f8 | 1205 | union sctp_addr from_addr; |
1da177e4 LT |
1206 | |
1207 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 1208 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1209 | |
1210 | /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */ | |
922dbc5b | 1211 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr) + |
edf903f8 | 1212 | sizeof(*hbinfo))) |
24cb81a6 | 1213 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1214 | commands); |
1215 | ||
edf903f8 | 1216 | hbinfo = (struct sctp_sender_hb_info *)chunk->skb->data; |
a601266e | 1217 | /* Make sure that the length of the parameter is what we expect */ |
edf903f8 | 1218 | if (ntohs(hbinfo->param_hdr.length) != sizeof(*hbinfo)) |
a601266e | 1219 | return SCTP_DISPOSITION_DISCARD; |
a601266e | 1220 | |
1da177e4 | 1221 | from_addr = hbinfo->daddr; |
63de08f4 | 1222 | link = sctp_assoc_lookup_paddr(asoc, &from_addr); |
1da177e4 LT |
1223 | |
1224 | /* This should never happen, but lets log it if so. */ | |
3f7a87d2 FF |
1225 | if (unlikely(!link)) { |
1226 | if (from_addr.sa.sa_family == AF_INET6) { | |
e87cc472 JP |
1227 | net_warn_ratelimited("%s association %p could not find address %pI6\n", |
1228 | __func__, | |
1229 | asoc, | |
1230 | &from_addr.v6.sin6_addr); | |
3f7a87d2 | 1231 | } else { |
e87cc472 JP |
1232 | net_warn_ratelimited("%s association %p could not find address %pI4\n", |
1233 | __func__, | |
1234 | asoc, | |
1235 | &from_addr.v4.sin_addr.s_addr); | |
3f7a87d2 | 1236 | } |
1da177e4 LT |
1237 | return SCTP_DISPOSITION_DISCARD; |
1238 | } | |
1239 | ||
ad8fec17 SS |
1240 | /* Validate the 64-bit random nonce. */ |
1241 | if (hbinfo->hb_nonce != link->hb_nonce) | |
1242 | return SCTP_DISPOSITION_DISCARD; | |
1243 | ||
52ccb8e9 | 1244 | max_interval = link->hbinterval + link->rto; |
1da177e4 LT |
1245 | |
1246 | /* Check if the timestamp looks valid. */ | |
1247 | if (time_after(hbinfo->sent_at, jiffies) || | |
1248 | time_after(jiffies, hbinfo->sent_at + max_interval)) { | |
bb33381d DB |
1249 | pr_debug("%s: HEARTBEAT ACK with invalid timestamp received " |
1250 | "for transport:%p\n", __func__, link); | |
1251 | ||
1da177e4 LT |
1252 | return SCTP_DISPOSITION_DISCARD; |
1253 | } | |
1254 | ||
1255 | /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of | |
1256 | * the HEARTBEAT should clear the error counter of the | |
1257 | * destination transport address to which the HEARTBEAT was | |
1258 | * sent and mark the destination transport address as active if | |
1259 | * it is not so marked. | |
1260 | */ | |
1261 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link)); | |
1262 | ||
1263 | return SCTP_DISPOSITION_CONSUME; | |
1264 | } | |
1265 | ||
1266 | /* Helper function to send out an abort for the restart | |
1267 | * condition. | |
1268 | */ | |
2ce95503 | 1269 | static int sctp_sf_send_restart_abort(struct net *net, union sctp_addr *ssa, |
1da177e4 | 1270 | struct sctp_chunk *init, |
a85bbeb2 | 1271 | struct sctp_cmd_seq *commands) |
1da177e4 | 1272 | { |
172a1599 | 1273 | struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family); |
1da177e4 LT |
1274 | union sctp_addr_param *addrparm; |
1275 | struct sctp_errhdr *errhdr; | |
d8238d9d | 1276 | char buffer[sizeof(*errhdr) + sizeof(*addrparm)]; |
172a1599 XL |
1277 | struct sctp_endpoint *ep; |
1278 | struct sctp_packet *pkt; | |
1279 | int len; | |
1da177e4 LT |
1280 | |
1281 | /* Build the error on the stack. We are way to malloc crazy | |
1282 | * throughout the code today. | |
1283 | */ | |
1284 | errhdr = (struct sctp_errhdr *)buffer; | |
1285 | addrparm = (union sctp_addr_param *)errhdr->variable; | |
1286 | ||
1287 | /* Copy into a parm format. */ | |
1288 | len = af->to_addr_param(ssa, addrparm); | |
d8238d9d | 1289 | len += sizeof(*errhdr); |
1da177e4 LT |
1290 | |
1291 | errhdr->cause = SCTP_ERROR_RESTART; | |
1292 | errhdr->length = htons(len); | |
1293 | ||
1294 | /* Assign to the control socket. */ | |
2ce95503 | 1295 | ep = sctp_sk(net->sctp.ctl_sock)->ep; |
1da177e4 LT |
1296 | |
1297 | /* Association is NULL since this may be a restart attack and we | |
1298 | * want to send back the attacker's vtag. | |
1299 | */ | |
24cb81a6 | 1300 | pkt = sctp_abort_pkt_new(net, ep, NULL, init, errhdr, len); |
1da177e4 LT |
1301 | |
1302 | if (!pkt) | |
1303 | goto out; | |
1304 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt)); | |
1305 | ||
b01a2407 | 1306 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
1307 | |
1308 | /* Discard the rest of the inbound packet. */ | |
1309 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); | |
1310 | ||
1311 | out: | |
1312 | /* Even if there is no memory, treat as a failure so | |
1313 | * the packet will get dropped. | |
1314 | */ | |
1315 | return 0; | |
1316 | } | |
1317 | ||
123031c0 JP |
1318 | static bool list_has_sctp_addr(const struct list_head *list, |
1319 | union sctp_addr *ipaddr) | |
1320 | { | |
1321 | struct sctp_transport *addr; | |
1322 | ||
1323 | list_for_each_entry(addr, list, transports) { | |
1324 | if (sctp_cmp_addr_exact(ipaddr, &addr->ipaddr)) | |
1325 | return true; | |
1326 | } | |
1327 | ||
1328 | return false; | |
1329 | } | |
1da177e4 LT |
1330 | /* A restart is occurring, check to make sure no new addresses |
1331 | * are being added as we may be under a takeover attack. | |
1332 | */ | |
1333 | static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, | |
1334 | const struct sctp_association *asoc, | |
1335 | struct sctp_chunk *init, | |
a85bbeb2 | 1336 | struct sctp_cmd_seq *commands) |
1da177e4 | 1337 | { |
2ce95503 | 1338 | struct net *net = sock_net(new_asoc->base.sk); |
123031c0 JP |
1339 | struct sctp_transport *new_addr; |
1340 | int ret = 1; | |
1da177e4 | 1341 | |
123031c0 | 1342 | /* Implementor's Guide - Section 5.2.2 |
1da177e4 LT |
1343 | * ... |
1344 | * Before responding the endpoint MUST check to see if the | |
1345 | * unexpected INIT adds new addresses to the association. If new | |
1346 | * addresses are added to the association, the endpoint MUST respond | |
1347 | * with an ABORT.. | |
1348 | */ | |
1349 | ||
1350 | /* Search through all current addresses and make sure | |
1351 | * we aren't adding any new ones. | |
1352 | */ | |
9dbc15f0 | 1353 | list_for_each_entry(new_addr, &new_asoc->peer.transport_addr_list, |
123031c0 JP |
1354 | transports) { |
1355 | if (!list_has_sctp_addr(&asoc->peer.transport_addr_list, | |
1356 | &new_addr->ipaddr)) { | |
2ce95503 | 1357 | sctp_sf_send_restart_abort(net, &new_addr->ipaddr, init, |
123031c0 JP |
1358 | commands); |
1359 | ret = 0; | |
1da177e4 | 1360 | break; |
123031c0 | 1361 | } |
1da177e4 LT |
1362 | } |
1363 | ||
1364 | /* Return success if all addresses were found. */ | |
123031c0 | 1365 | return ret; |
1da177e4 LT |
1366 | } |
1367 | ||
1368 | /* Populate the verification/tie tags based on overlapping INIT | |
1369 | * scenario. | |
1370 | * | |
1371 | * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state. | |
1372 | */ | |
1373 | static void sctp_tietags_populate(struct sctp_association *new_asoc, | |
1374 | const struct sctp_association *asoc) | |
1375 | { | |
1376 | switch (asoc->state) { | |
1377 | ||
1378 | /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */ | |
1379 | ||
1380 | case SCTP_STATE_COOKIE_WAIT: | |
1381 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1382 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1383 | new_asoc->c.peer_ttag = 0; | |
1384 | break; | |
1385 | ||
1386 | case SCTP_STATE_COOKIE_ECHOED: | |
1387 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1388 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1389 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1390 | break; | |
1391 | ||
1392 | /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED, | |
1393 | * COOKIE-WAIT and SHUTDOWN-ACK-SENT | |
1394 | */ | |
1395 | default: | |
1396 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1397 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1398 | break; | |
3ff50b79 | 1399 | } |
1da177e4 LT |
1400 | |
1401 | /* Other parameters for the endpoint SHOULD be copied from the | |
1402 | * existing parameters of the association (e.g. number of | |
1403 | * outbound streams) into the INIT ACK and cookie. | |
1404 | */ | |
1405 | new_asoc->rwnd = asoc->rwnd; | |
1406 | new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams; | |
1407 | new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams; | |
1408 | new_asoc->c.initial_tsn = asoc->c.initial_tsn; | |
1409 | } | |
1410 | ||
1411 | /* | |
1412 | * Compare vtag/tietag values to determine unexpected COOKIE-ECHO | |
1413 | * handling action. | |
1414 | * | |
1415 | * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists. | |
1416 | * | |
1417 | * Returns value representing action to be taken. These action values | |
1418 | * correspond to Action/Description values in RFC 2960, Table 2. | |
1419 | */ | |
1420 | static char sctp_tietags_compare(struct sctp_association *new_asoc, | |
1421 | const struct sctp_association *asoc) | |
1422 | { | |
1423 | /* In this case, the peer may have restarted. */ | |
1424 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1425 | (asoc->c.peer_vtag != new_asoc->c.peer_vtag) && | |
1426 | (asoc->c.my_vtag == new_asoc->c.my_ttag) && | |
1427 | (asoc->c.peer_vtag == new_asoc->c.peer_ttag)) | |
1428 | return 'A'; | |
1429 | ||
1430 | /* Collision case B. */ | |
1431 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1432 | ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) || | |
1433 | (0 == asoc->c.peer_vtag))) { | |
1434 | return 'B'; | |
1435 | } | |
1436 | ||
1437 | /* Collision case D. */ | |
1438 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1439 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag)) | |
1440 | return 'D'; | |
1441 | ||
1442 | /* Collision case C. */ | |
1443 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1444 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag) && | |
1445 | (0 == new_asoc->c.my_ttag) && | |
1446 | (0 == new_asoc->c.peer_ttag)) | |
1447 | return 'C'; | |
1448 | ||
1449 | /* No match to any of the special cases; discard this packet. */ | |
1450 | return 'E'; | |
1451 | } | |
1452 | ||
1453 | /* Common helper routine for both duplicate and simulataneous INIT | |
1454 | * chunk handling. | |
1455 | */ | |
172a1599 XL |
1456 | static enum sctp_disposition sctp_sf_do_unexpected_init( |
1457 | struct net *net, | |
1458 | const struct sctp_endpoint *ep, | |
1459 | const struct sctp_association *asoc, | |
1460 | const union sctp_subtype type, | |
1461 | void *arg, | |
1462 | struct sctp_cmd_seq *commands) | |
1da177e4 | 1463 | { |
62e6b7e4 XL |
1464 | struct sctp_chunk *chunk = arg, *repl, *err_chunk; |
1465 | struct sctp_unrecognized_param *unk_param; | |
1da177e4 | 1466 | struct sctp_association *new_asoc; |
172a1599 | 1467 | enum sctp_disposition retval; |
1da177e4 | 1468 | struct sctp_packet *packet; |
1da177e4 LT |
1469 | int len; |
1470 | ||
2277c7cd RH |
1471 | /* Update socket peer label if first association. */ |
1472 | if (security_sctp_assoc_request((struct sctp_endpoint *)ep, | |
1473 | chunk->skb)) | |
1474 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
1475 | ||
1da177e4 LT |
1476 | /* 6.10 Bundling |
1477 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
1478 | * SHUTDOWN COMPLETE with any other chunks. | |
1479 | * | |
1480 | * IG Section 2.11.2 | |
1481 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
1482 | * enforce these rules by silently discarding an arriving packet | |
1483 | * with an INIT chunk that is bundled with other chunks. | |
1484 | */ | |
1485 | if (!chunk->singleton) | |
24cb81a6 | 1486 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1487 | |
1488 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification | |
d808ad9a | 1489 | * Tag. |
1da177e4 LT |
1490 | */ |
1491 | if (chunk->sctp_hdr->vtag != 0) | |
24cb81a6 | 1492 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1493 | |
1494 | /* Make sure that the INIT chunk has a valid length. | |
1495 | * In this case, we generate a protocol violation since we have | |
1496 | * an association established. | |
1497 | */ | |
01a992be | 1498 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_init_chunk))) |
24cb81a6 | 1499 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
1500 | commands); |
1501 | /* Grab the INIT header. */ | |
4ae70c08 | 1502 | chunk->subh.init_hdr = (struct sctp_inithdr *)chunk->skb->data; |
1da177e4 LT |
1503 | |
1504 | /* Tag the variable length parameters. */ | |
4ae70c08 | 1505 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(struct sctp_inithdr)); |
1da177e4 LT |
1506 | |
1507 | /* Verify the INIT chunk before processing it. */ | |
1508 | err_chunk = NULL; | |
b14878cc | 1509 | if (!sctp_verify_init(net, ep, asoc, chunk->chunk_hdr->type, |
01a992be | 1510 | (struct sctp_init_chunk *)chunk->chunk_hdr, chunk, |
1da177e4 LT |
1511 | &err_chunk)) { |
1512 | /* This chunk contains fatal error. It is to be discarded. | |
1513 | * Send an ABORT, with causes if there is any. | |
1514 | */ | |
1515 | if (err_chunk) { | |
24cb81a6 | 1516 | packet = sctp_abort_pkt_new(net, ep, asoc, arg, |
1da177e4 | 1517 | (__u8 *)(err_chunk->chunk_hdr) + |
922dbc5b | 1518 | sizeof(struct sctp_chunkhdr), |
1da177e4 | 1519 | ntohs(err_chunk->chunk_hdr->length) - |
922dbc5b | 1520 | sizeof(struct sctp_chunkhdr)); |
1da177e4 LT |
1521 | |
1522 | if (packet) { | |
1523 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
1524 | SCTP_PACKET(packet)); | |
24cb81a6 | 1525 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
1526 | retval = SCTP_DISPOSITION_CONSUME; |
1527 | } else { | |
1528 | retval = SCTP_DISPOSITION_NOMEM; | |
1529 | } | |
1530 | goto cleanup; | |
1531 | } else { | |
24cb81a6 | 1532 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, |
1da177e4 LT |
1533 | commands); |
1534 | } | |
1535 | } | |
1536 | ||
1537 | /* | |
1538 | * Other parameters for the endpoint SHOULD be copied from the | |
1539 | * existing parameters of the association (e.g. number of | |
1540 | * outbound streams) into the INIT ACK and cookie. | |
1541 | * FIXME: We are copying parameters from the endpoint not the | |
1542 | * association. | |
1543 | */ | |
1544 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
1545 | if (!new_asoc) | |
1546 | goto nomem; | |
1547 | ||
409b95af VY |
1548 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
1549 | sctp_scope(sctp_source(chunk)), GFP_ATOMIC) < 0) | |
1550 | goto nomem; | |
1551 | ||
1da177e4 LT |
1552 | /* In the outbound INIT ACK the endpoint MUST copy its current |
1553 | * Verification Tag and Peers Verification tag into a reserved | |
1554 | * place (local tie-tag and per tie-tag) within the state cookie. | |
1555 | */ | |
de6becdc | 1556 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), |
01a992be | 1557 | (struct sctp_init_chunk *)chunk->chunk_hdr, |
df7deeb5 VY |
1558 | GFP_ATOMIC)) |
1559 | goto nomem; | |
1da177e4 LT |
1560 | |
1561 | /* Make sure no new addresses are being added during the | |
1562 | * restart. Do not do this check for COOKIE-WAIT state, | |
1563 | * since there are no peer addresses to check against. | |
1564 | * Upon return an ABORT will have been sent if needed. | |
1565 | */ | |
1566 | if (!sctp_state(asoc, COOKIE_WAIT)) { | |
1567 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, | |
1568 | commands)) { | |
1569 | retval = SCTP_DISPOSITION_CONSUME; | |
df7deeb5 | 1570 | goto nomem_retval; |
1da177e4 LT |
1571 | } |
1572 | } | |
1573 | ||
1574 | sctp_tietags_populate(new_asoc, asoc); | |
1575 | ||
1576 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ | |
1577 | ||
1578 | /* If there are errors need to be reported for unknown parameters, | |
1579 | * make sure to reserve enough room in the INIT ACK for them. | |
1580 | */ | |
1581 | len = 0; | |
1582 | if (err_chunk) { | |
1583 | len = ntohs(err_chunk->chunk_hdr->length) - | |
922dbc5b | 1584 | sizeof(struct sctp_chunkhdr); |
1da177e4 LT |
1585 | } |
1586 | ||
1da177e4 LT |
1587 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
1588 | if (!repl) | |
1589 | goto nomem; | |
1590 | ||
1591 | /* If there are errors need to be reported for unknown parameters, | |
1592 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
1593 | * parameter. | |
1594 | */ | |
1595 | if (err_chunk) { | |
1596 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
1597 | * ERROR chunk generated by sctp_verify_init(). Since the | |
1598 | * error cause code for "unknown parameter" and the | |
1599 | * "Unrecognized parameter" type is the same, we can | |
1600 | * construct the parameters in INIT ACK by copying the | |
1601 | * ERROR causes over. | |
1602 | */ | |
62e6b7e4 | 1603 | unk_param = (struct sctp_unrecognized_param *) |
1da177e4 | 1604 | ((__u8 *)(err_chunk->chunk_hdr) + |
922dbc5b | 1605 | sizeof(struct sctp_chunkhdr)); |
1da177e4 LT |
1606 | /* Replace the cause code with the "Unrecognized parameter" |
1607 | * parameter type. | |
1608 | */ | |
1609 | sctp_addto_chunk(repl, len, unk_param); | |
1610 | } | |
1611 | ||
1612 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1613 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1614 | ||
1615 | /* | |
1616 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
1617 | * "Z" MUST NOT allocate any resources for this new association. | |
1618 | * Otherwise, "Z" will be vulnerable to resource attacks. | |
1619 | */ | |
1620 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1621 | retval = SCTP_DISPOSITION_CONSUME; | |
1622 | ||
df7deeb5 VY |
1623 | return retval; |
1624 | ||
1625 | nomem: | |
1626 | retval = SCTP_DISPOSITION_NOMEM; | |
1627 | nomem_retval: | |
1628 | if (new_asoc) | |
1629 | sctp_association_free(new_asoc); | |
1da177e4 LT |
1630 | cleanup: |
1631 | if (err_chunk) | |
1632 | sctp_chunk_free(err_chunk); | |
1633 | return retval; | |
1da177e4 LT |
1634 | } |
1635 | ||
1636 | /* | |
25985edc | 1637 | * Handle simultaneous INIT. |
1da177e4 LT |
1638 | * This means we started an INIT and then we got an INIT request from |
1639 | * our peer. | |
1640 | * | |
1641 | * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B) | |
1642 | * This usually indicates an initialization collision, i.e., each | |
1643 | * endpoint is attempting, at about the same time, to establish an | |
1644 | * association with the other endpoint. | |
1645 | * | |
1646 | * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an | |
1647 | * endpoint MUST respond with an INIT ACK using the same parameters it | |
1648 | * sent in its original INIT chunk (including its Verification Tag, | |
1649 | * unchanged). These original parameters are combined with those from the | |
1650 | * newly received INIT chunk. The endpoint shall also generate a State | |
1651 | * Cookie with the INIT ACK. The endpoint uses the parameters sent in its | |
1652 | * INIT to calculate the State Cookie. | |
1653 | * | |
1654 | * After that, the endpoint MUST NOT change its state, the T1-init | |
1655 | * timer shall be left running and the corresponding TCB MUST NOT be | |
1656 | * destroyed. The normal procedures for handling State Cookies when | |
1657 | * a TCB exists will resolve the duplicate INITs to a single association. | |
1658 | * | |
1659 | * For an endpoint that is in the COOKIE-ECHOED state it MUST populate | |
1660 | * its Tie-Tags with the Tag information of itself and its peer (see | |
1661 | * section 5.2.2 for a description of the Tie-Tags). | |
1662 | * | |
1663 | * Verification Tag: Not explicit, but an INIT can not have a valid | |
1664 | * verification tag, so we skip the check. | |
1665 | * | |
1666 | * Inputs | |
1667 | * (endpoint, asoc, chunk) | |
1668 | * | |
1669 | * Outputs | |
1670 | * (asoc, reply_msg, msg_up, timers, counters) | |
1671 | * | |
1672 | * The return value is the disposition of the chunk. | |
1673 | */ | |
172a1599 XL |
1674 | enum sctp_disposition sctp_sf_do_5_2_1_siminit( |
1675 | struct net *net, | |
1676 | const struct sctp_endpoint *ep, | |
1677 | const struct sctp_association *asoc, | |
1678 | const union sctp_subtype type, | |
1679 | void *arg, | |
1680 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
1681 | { |
1682 | /* Call helper to do the real work for both simulataneous and | |
1683 | * duplicate INIT chunk handling. | |
1684 | */ | |
24cb81a6 | 1685 | return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1686 | } |
1687 | ||
1688 | /* | |
1689 | * Handle duplicated INIT messages. These are usually delayed | |
1690 | * restransmissions. | |
1691 | * | |
1692 | * Section: 5.2.2 Unexpected INIT in States Other than CLOSED, | |
1693 | * COOKIE-ECHOED and COOKIE-WAIT | |
1694 | * | |
1695 | * Unless otherwise stated, upon reception of an unexpected INIT for | |
1696 | * this association, the endpoint shall generate an INIT ACK with a | |
1697 | * State Cookie. In the outbound INIT ACK the endpoint MUST copy its | |
1698 | * current Verification Tag and peer's Verification Tag into a reserved | |
1699 | * place within the state cookie. We shall refer to these locations as | |
1700 | * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet | |
1701 | * containing this INIT ACK MUST carry a Verification Tag value equal to | |
1702 | * the Initiation Tag found in the unexpected INIT. And the INIT ACK | |
1703 | * MUST contain a new Initiation Tag (randomly generated see Section | |
1704 | * 5.3.1). Other parameters for the endpoint SHOULD be copied from the | |
1705 | * existing parameters of the association (e.g. number of outbound | |
1706 | * streams) into the INIT ACK and cookie. | |
1707 | * | |
1708 | * After sending out the INIT ACK, the endpoint shall take no further | |
1709 | * actions, i.e., the existing association, including its current state, | |
1710 | * and the corresponding TCB MUST NOT be changed. | |
1711 | * | |
1712 | * Note: Only when a TCB exists and the association is not in a COOKIE- | |
1713 | * WAIT state are the Tie-Tags populated. For a normal association INIT | |
1714 | * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be | |
1715 | * set to 0 (indicating that no previous TCB existed). The INIT ACK and | |
1716 | * State Cookie are populated as specified in section 5.2.1. | |
1717 | * | |
1718 | * Verification Tag: Not specified, but an INIT has no way of knowing | |
1719 | * what the verification tag could be, so we ignore it. | |
1720 | * | |
1721 | * Inputs | |
1722 | * (endpoint, asoc, chunk) | |
1723 | * | |
1724 | * Outputs | |
1725 | * (asoc, reply_msg, msg_up, timers, counters) | |
1726 | * | |
1727 | * The return value is the disposition of the chunk. | |
1728 | */ | |
172a1599 XL |
1729 | enum sctp_disposition sctp_sf_do_5_2_2_dupinit( |
1730 | struct net *net, | |
24cb81a6 | 1731 | const struct sctp_endpoint *ep, |
1da177e4 | 1732 | const struct sctp_association *asoc, |
bfc6f827 | 1733 | const union sctp_subtype type, |
1da177e4 | 1734 | void *arg, |
a85bbeb2 | 1735 | struct sctp_cmd_seq *commands) |
1da177e4 LT |
1736 | { |
1737 | /* Call helper to do the real work for both simulataneous and | |
1738 | * duplicate INIT chunk handling. | |
1739 | */ | |
24cb81a6 | 1740 | return sctp_sf_do_unexpected_init(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
1741 | } |
1742 | ||
1743 | ||
610ab73a VY |
1744 | /* |
1745 | * Unexpected INIT-ACK handler. | |
1746 | * | |
1747 | * Section 5.2.3 | |
1748 | * If an INIT ACK received by an endpoint in any state other than the | |
1749 | * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk. | |
1750 | * An unexpected INIT ACK usually indicates the processing of an old or | |
1751 | * duplicated INIT chunk. | |
1752 | */ | |
172a1599 XL |
1753 | enum sctp_disposition sctp_sf_do_5_2_3_initack( |
1754 | struct net *net, | |
1755 | const struct sctp_endpoint *ep, | |
1756 | const struct sctp_association *asoc, | |
1757 | const union sctp_subtype type, | |
1758 | void *arg, | |
1759 | struct sctp_cmd_seq *commands) | |
610ab73a VY |
1760 | { |
1761 | /* Per the above section, we'll discard the chunk if we have an | |
1762 | * endpoint. If this is an OOTB INIT-ACK, treat it as such. | |
1763 | */ | |
2ce95503 | 1764 | if (ep == sctp_sk(net->sctp.ctl_sock)->ep) |
24cb81a6 | 1765 | return sctp_sf_ootb(net, ep, asoc, type, arg, commands); |
610ab73a | 1766 | else |
24cb81a6 | 1767 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
610ab73a | 1768 | } |
1da177e4 LT |
1769 | |
1770 | /* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A') | |
1771 | * | |
1772 | * Section 5.2.4 | |
1773 | * A) In this case, the peer may have restarted. | |
1774 | */ | |
172a1599 XL |
1775 | static enum sctp_disposition sctp_sf_do_dupcook_a( |
1776 | struct net *net, | |
24cb81a6 | 1777 | const struct sctp_endpoint *ep, |
1da177e4 LT |
1778 | const struct sctp_association *asoc, |
1779 | struct sctp_chunk *chunk, | |
a85bbeb2 | 1780 | struct sctp_cmd_seq *commands, |
1da177e4 LT |
1781 | struct sctp_association *new_asoc) |
1782 | { | |
01a992be | 1783 | struct sctp_init_chunk *peer_init; |
172a1599 | 1784 | enum sctp_disposition disposition; |
1da177e4 LT |
1785 | struct sctp_ulpevent *ev; |
1786 | struct sctp_chunk *repl; | |
1787 | struct sctp_chunk *err; | |
1da177e4 LT |
1788 | |
1789 | /* new_asoc is a brand-new association, so these are not yet | |
1790 | * side effects--it is safe to run them here. | |
1791 | */ | |
1792 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1793 | ||
de6becdc | 1794 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init, |
1da177e4 LT |
1795 | GFP_ATOMIC)) |
1796 | goto nomem; | |
1797 | ||
4842a08f XL |
1798 | if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) |
1799 | goto nomem; | |
1800 | ||
59d8d443 XL |
1801 | if (!sctp_auth_chunk_verify(net, chunk, new_asoc)) |
1802 | return SCTP_DISPOSITION_DISCARD; | |
1803 | ||
1da177e4 LT |
1804 | /* Make sure no new addresses are being added during the |
1805 | * restart. Though this is a pretty complicated attack | |
1806 | * since you'd have to get inside the cookie. | |
1807 | */ | |
59d8d443 | 1808 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) |
1da177e4 | 1809 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
1810 | |
1811 | /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes | |
1812 | * the peer has restarted (Action A), it MUST NOT setup a new | |
1813 | * association but instead resend the SHUTDOWN ACK and send an ERROR | |
1814 | * chunk with a "Cookie Received while Shutting Down" error cause to | |
1815 | * its peer. | |
1816 | */ | |
1817 | if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) { | |
24cb81a6 | 1818 | disposition = sctp_sf_do_9_2_reshutack(net, ep, asoc, |
1da177e4 LT |
1819 | SCTP_ST_CHUNK(chunk->chunk_hdr->type), |
1820 | chunk, commands); | |
1821 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
1822 | goto nomem; | |
1823 | ||
1824 | err = sctp_make_op_error(asoc, chunk, | |
1825 | SCTP_ERROR_COOKIE_IN_SHUTDOWN, | |
6383cfb3 | 1826 | NULL, 0, 0); |
1da177e4 LT |
1827 | if (err) |
1828 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1829 | SCTP_CHUNK(err)); | |
1830 | ||
1831 | return SCTP_DISPOSITION_CONSUME; | |
1832 | } | |
1833 | ||
a000c01e WY |
1834 | /* For now, stop pending T3-rtx and SACK timers, fail any unsent/unacked |
1835 | * data. Consider the optional choice of resending of this data. | |
1da177e4 | 1836 | */ |
a000c01e WY |
1837 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); |
1838 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1839 | SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); | |
1da177e4 LT |
1840 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL()); |
1841 | ||
a000c01e WY |
1842 | /* Stop pending T4-rto timer, teardown ASCONF queue, ASCONF-ACK queue |
1843 | * and ASCONF-ACK cache. | |
1844 | */ | |
1845 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1846 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
1847 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_ASCONF_QUEUE, SCTP_NULL()); | |
1848 | ||
1da177e4 LT |
1849 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
1850 | if (!repl) | |
1851 | goto nomem; | |
1852 | ||
1da177e4 LT |
1853 | /* Report association restart to upper layer. */ |
1854 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0, | |
1855 | new_asoc->c.sinit_num_ostreams, | |
1856 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 1857 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1858 | if (!ev) |
1859 | goto nomem_ev; | |
1860 | ||
df7deeb5 VY |
1861 | /* Update the content of current association. */ |
1862 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1da177e4 | 1863 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
bdf6fa52 VY |
1864 | if (sctp_state(asoc, SHUTDOWN_PENDING) && |
1865 | (sctp_sstate(asoc->base.sk, CLOSING) || | |
1866 | sock_flag(asoc->base.sk, SOCK_DEAD))) { | |
1867 | /* if were currently in SHUTDOWN_PENDING, but the socket | |
1868 | * has been closed by user, don't transition to ESTABLISHED. | |
1869 | * Instead trigger SHUTDOWN bundled with COOKIE_ACK. | |
1870 | */ | |
1871 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1872 | return sctp_sf_do_9_2_start_shutdown(net, ep, asoc, | |
1873 | SCTP_ST_CHUNK(0), NULL, | |
1874 | commands); | |
1875 | } else { | |
1876 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1877 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1878 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1879 | } | |
1da177e4 LT |
1880 | return SCTP_DISPOSITION_CONSUME; |
1881 | ||
1882 | nomem_ev: | |
1883 | sctp_chunk_free(repl); | |
1884 | nomem: | |
1885 | return SCTP_DISPOSITION_NOMEM; | |
1886 | } | |
1887 | ||
1888 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B') | |
1889 | * | |
1890 | * Section 5.2.4 | |
1891 | * B) In this case, both sides may be attempting to start an association | |
1892 | * at about the same time but the peer endpoint started its INIT | |
1893 | * after responding to the local endpoint's INIT | |
1894 | */ | |
1895 | /* This case represents an initialization collision. */ | |
172a1599 XL |
1896 | static enum sctp_disposition sctp_sf_do_dupcook_b( |
1897 | struct net *net, | |
24cb81a6 | 1898 | const struct sctp_endpoint *ep, |
1da177e4 LT |
1899 | const struct sctp_association *asoc, |
1900 | struct sctp_chunk *chunk, | |
a85bbeb2 | 1901 | struct sctp_cmd_seq *commands, |
1da177e4 LT |
1902 | struct sctp_association *new_asoc) |
1903 | { | |
01a992be | 1904 | struct sctp_init_chunk *peer_init; |
1da177e4 LT |
1905 | struct sctp_chunk *repl; |
1906 | ||
1907 | /* new_asoc is a brand-new association, so these are not yet | |
1908 | * side effects--it is safe to run them here. | |
1909 | */ | |
1910 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
de6becdc | 1911 | if (!sctp_process_init(new_asoc, chunk, sctp_source(chunk), peer_init, |
1da177e4 LT |
1912 | GFP_ATOMIC)) |
1913 | goto nomem; | |
1914 | ||
4842a08f XL |
1915 | if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC)) |
1916 | goto nomem; | |
1917 | ||
59d8d443 XL |
1918 | if (!sctp_auth_chunk_verify(net, chunk, new_asoc)) |
1919 | return SCTP_DISPOSITION_DISCARD; | |
1920 | ||
1da177e4 LT |
1921 | /* Update the content of current association. */ |
1922 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1923 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1924 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
24cb81a6 | 1925 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
1da177e4 LT |
1926 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); |
1927 | ||
1928 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1929 | if (!repl) | |
1930 | goto nomem; | |
1931 | ||
1932 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1933 | |
1934 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1935 | * | |
1936 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
1937 | * send the Communication Up notification to the SCTP user | |
1938 | * upon reception of a valid COOKIE ECHO chunk. | |
07d93967 VY |
1939 | * |
1940 | * Sadly, this needs to be implemented as a side-effect, because | |
1941 | * we are not guaranteed to have set the association id of the real | |
1942 | * association and so these notifications need to be delayed until | |
1943 | * the association id is allocated. | |
1da177e4 | 1944 | */ |
1da177e4 | 1945 | |
07d93967 | 1946 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP)); |
1da177e4 LT |
1947 | |
1948 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1949 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 1950 | * delivers this notification to inform the application that of the |
0f3fffd8 | 1951 | * peers requested adaptation layer. |
07d93967 VY |
1952 | * |
1953 | * This also needs to be done as a side effect for the same reason as | |
1954 | * above. | |
1da177e4 | 1955 | */ |
07d93967 VY |
1956 | if (asoc->peer.adaptation_ind) |
1957 | sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL()); | |
1da177e4 | 1958 | |
30f6ebf6 XL |
1959 | if (!asoc->peer.auth_capable) |
1960 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_NO_AUTH, SCTP_NULL()); | |
1961 | ||
1da177e4 LT |
1962 | return SCTP_DISPOSITION_CONSUME; |
1963 | ||
1da177e4 LT |
1964 | nomem: |
1965 | return SCTP_DISPOSITION_NOMEM; | |
1966 | } | |
1967 | ||
1968 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C') | |
1969 | * | |
1970 | * Section 5.2.4 | |
1971 | * C) In this case, the local endpoint's cookie has arrived late. | |
1972 | * Before it arrived, the local endpoint sent an INIT and received an | |
1973 | * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag | |
1974 | * but a new tag of its own. | |
1975 | */ | |
1976 | /* This case represents an initialization collision. */ | |
172a1599 XL |
1977 | static enum sctp_disposition sctp_sf_do_dupcook_c( |
1978 | struct net *net, | |
24cb81a6 | 1979 | const struct sctp_endpoint *ep, |
1da177e4 LT |
1980 | const struct sctp_association *asoc, |
1981 | struct sctp_chunk *chunk, | |
a85bbeb2 | 1982 | struct sctp_cmd_seq *commands, |
1da177e4 LT |
1983 | struct sctp_association *new_asoc) |
1984 | { | |
1985 | /* The cookie should be silently discarded. | |
1986 | * The endpoint SHOULD NOT change states and should leave | |
1987 | * any timers running. | |
1988 | */ | |
1989 | return SCTP_DISPOSITION_DISCARD; | |
1990 | } | |
1991 | ||
1992 | /* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D') | |
1993 | * | |
1994 | * Section 5.2.4 | |
1995 | * | |
1996 | * D) When both local and remote tags match the endpoint should always | |
1997 | * enter the ESTABLISHED state, if it has not already done so. | |
1998 | */ | |
1999 | /* This case represents an initialization collision. */ | |
172a1599 XL |
2000 | static enum sctp_disposition sctp_sf_do_dupcook_d( |
2001 | struct net *net, | |
24cb81a6 | 2002 | const struct sctp_endpoint *ep, |
1da177e4 LT |
2003 | const struct sctp_association *asoc, |
2004 | struct sctp_chunk *chunk, | |
a85bbeb2 | 2005 | struct sctp_cmd_seq *commands, |
1da177e4 LT |
2006 | struct sctp_association *new_asoc) |
2007 | { | |
30f6ebf6 | 2008 | struct sctp_ulpevent *ev = NULL, *ai_ev = NULL, *auth_ev = NULL; |
1da177e4 LT |
2009 | struct sctp_chunk *repl; |
2010 | ||
2011 | /* Clarification from Implementor's Guide: | |
2012 | * D) When both local and remote tags match the endpoint should | |
d808ad9a YH |
2013 | * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state. |
2014 | * It should stop any cookie timer that may be running and send | |
2015 | * a COOKIE ACK. | |
1da177e4 LT |
2016 | */ |
2017 | ||
59d8d443 XL |
2018 | if (!sctp_auth_chunk_verify(net, chunk, asoc)) |
2019 | return SCTP_DISPOSITION_DISCARD; | |
2020 | ||
1da177e4 LT |
2021 | /* Don't accidentally move back into established state. */ |
2022 | if (asoc->state < SCTP_STATE_ESTABLISHED) { | |
2023 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2024 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2025 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2026 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
24cb81a6 | 2027 | SCTP_INC_STATS(net, SCTP_MIB_CURRESTAB); |
1da177e4 LT |
2028 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, |
2029 | SCTP_NULL()); | |
2030 | ||
2031 | /* RFC 2960 5.1 Normal Establishment of an Association | |
2032 | * | |
2033 | * D) IMPLEMENTATION NOTE: An implementation may choose | |
2034 | * to send the Communication Up notification to the | |
2035 | * SCTP user upon reception of a valid COOKIE | |
2036 | * ECHO chunk. | |
2037 | */ | |
df7deeb5 | 2038 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, |
1da177e4 | 2039 | SCTP_COMM_UP, 0, |
df7deeb5 VY |
2040 | asoc->c.sinit_num_ostreams, |
2041 | asoc->c.sinit_max_instreams, | |
9cbcbf4e | 2042 | NULL, GFP_ATOMIC); |
1da177e4 LT |
2043 | if (!ev) |
2044 | goto nomem; | |
1da177e4 LT |
2045 | |
2046 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 2047 | * When a peer sends a Adaptation Layer Indication parameter, |
1da177e4 | 2048 | * SCTP delivers this notification to inform the application |
0f3fffd8 | 2049 | * that of the peers requested adaptation layer. |
1da177e4 | 2050 | */ |
0f3fffd8 ISJ |
2051 | if (asoc->peer.adaptation_ind) { |
2052 | ai_ev = sctp_ulpevent_make_adaptation_indication(asoc, | |
1da177e4 | 2053 | GFP_ATOMIC); |
df7deeb5 | 2054 | if (!ai_ev) |
1da177e4 LT |
2055 | goto nomem; |
2056 | ||
1da177e4 | 2057 | } |
30f6ebf6 XL |
2058 | |
2059 | if (!asoc->peer.auth_capable) { | |
2060 | auth_ev = sctp_ulpevent_make_authkey(asoc, 0, | |
2061 | SCTP_AUTH_NO_AUTH, | |
2062 | GFP_ATOMIC); | |
2063 | if (!auth_ev) | |
2064 | goto nomem; | |
2065 | } | |
1da177e4 | 2066 | } |
1da177e4 | 2067 | |
46e16d4b | 2068 | repl = sctp_make_cookie_ack(asoc, chunk); |
1da177e4 LT |
2069 | if (!repl) |
2070 | goto nomem; | |
2071 | ||
2e3216cd VY |
2072 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
2073 | ||
df7deeb5 VY |
2074 | if (ev) |
2075 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
2076 | SCTP_ULPEVENT(ev)); | |
2077 | if (ai_ev) | |
2078 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
2079 | SCTP_ULPEVENT(ai_ev)); | |
30f6ebf6 XL |
2080 | if (auth_ev) |
2081 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
2082 | SCTP_ULPEVENT(auth_ev)); | |
df7deeb5 | 2083 | |
1da177e4 LT |
2084 | return SCTP_DISPOSITION_CONSUME; |
2085 | ||
2086 | nomem: | |
30f6ebf6 XL |
2087 | if (auth_ev) |
2088 | sctp_ulpevent_free(auth_ev); | |
df7deeb5 VY |
2089 | if (ai_ev) |
2090 | sctp_ulpevent_free(ai_ev); | |
1da177e4 LT |
2091 | if (ev) |
2092 | sctp_ulpevent_free(ev); | |
2093 | return SCTP_DISPOSITION_NOMEM; | |
2094 | } | |
2095 | ||
2096 | /* | |
2097 | * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying | |
2098 | * chunk was retransmitted and then delayed in the network. | |
2099 | * | |
2100 | * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists | |
2101 | * | |
2102 | * Verification Tag: None. Do cookie validation. | |
2103 | * | |
2104 | * Inputs | |
2105 | * (endpoint, asoc, chunk) | |
2106 | * | |
2107 | * Outputs | |
2108 | * (asoc, reply_msg, msg_up, timers, counters) | |
2109 | * | |
2110 | * The return value is the disposition of the chunk. | |
2111 | */ | |
172a1599 XL |
2112 | enum sctp_disposition sctp_sf_do_5_2_4_dupcook( |
2113 | struct net *net, | |
24cb81a6 | 2114 | const struct sctp_endpoint *ep, |
1da177e4 | 2115 | const struct sctp_association *asoc, |
bfc6f827 | 2116 | const union sctp_subtype type, |
1da177e4 | 2117 | void *arg, |
a85bbeb2 | 2118 | struct sctp_cmd_seq *commands) |
1da177e4 | 2119 | { |
1da177e4 | 2120 | struct sctp_association *new_asoc; |
172a1599 XL |
2121 | struct sctp_chunk *chunk = arg; |
2122 | enum sctp_disposition retval; | |
2123 | struct sctp_chunk *err_chk_p; | |
1da177e4 LT |
2124 | int error = 0; |
2125 | char action; | |
1da177e4 LT |
2126 | |
2127 | /* Make sure that the chunk has a valid length from the protocol | |
2128 | * perspective. In this case check to make sure we have at least | |
2129 | * enough for the chunk header. Cookie length verification is | |
2130 | * done later. | |
2131 | */ | |
922dbc5b | 2132 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 2133 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2134 | commands); |
2135 | ||
2136 | /* "Decode" the chunk. We have no optional parameters so we | |
2137 | * are in good shape. | |
2138 | */ | |
d808ad9a | 2139 | chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 | 2140 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
922dbc5b | 2141 | sizeof(struct sctp_chunkhdr))) |
62b08083 | 2142 | goto nomem; |
1da177e4 LT |
2143 | |
2144 | /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie | |
2145 | * of a duplicate COOKIE ECHO match the Verification Tags of the | |
2146 | * current association, consider the State Cookie valid even if | |
2147 | * the lifespan is exceeded. | |
2148 | */ | |
2149 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
2150 | &err_chk_p); | |
2151 | ||
2152 | /* FIXME: | |
2153 | * If the re-build failed, what is the proper error path | |
2154 | * from here? | |
2155 | * | |
2156 | * [We should abort the association. --piggy] | |
2157 | */ | |
2158 | if (!new_asoc) { | |
2159 | /* FIXME: Several errors are possible. A bad cookie should | |
2160 | * be silently discarded, but think about logging it too. | |
2161 | */ | |
2162 | switch (error) { | |
2163 | case -SCTP_IERROR_NOMEM: | |
2164 | goto nomem; | |
2165 | ||
2166 | case -SCTP_IERROR_STALE_COOKIE: | |
24cb81a6 | 2167 | sctp_send_stale_cookie_err(net, ep, asoc, chunk, commands, |
1da177e4 | 2168 | err_chk_p); |
24cb81a6 | 2169 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2170 | case -SCTP_IERROR_BAD_SIG: |
2171 | default: | |
24cb81a6 | 2172 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
3ff50b79 | 2173 | } |
1da177e4 LT |
2174 | } |
2175 | ||
2277c7cd RH |
2176 | /* Update socket peer label if first association. */ |
2177 | if (security_sctp_assoc_request((struct sctp_endpoint *)ep, | |
2178 | chunk->skb)) | |
2179 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
2180 | ||
7e062977 XL |
2181 | /* Set temp so that it won't be added into hashtable */ |
2182 | new_asoc->temp = 1; | |
2183 | ||
1da177e4 LT |
2184 | /* Compare the tie_tag in cookie with the verification tag of |
2185 | * current association. | |
2186 | */ | |
2187 | action = sctp_tietags_compare(new_asoc, asoc); | |
2188 | ||
2189 | switch (action) { | |
2190 | case 'A': /* Association restart. */ | |
24cb81a6 | 2191 | retval = sctp_sf_do_dupcook_a(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2192 | new_asoc); |
2193 | break; | |
2194 | ||
2195 | case 'B': /* Collision case B. */ | |
24cb81a6 | 2196 | retval = sctp_sf_do_dupcook_b(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2197 | new_asoc); |
2198 | break; | |
2199 | ||
2200 | case 'C': /* Collision case C. */ | |
24cb81a6 | 2201 | retval = sctp_sf_do_dupcook_c(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2202 | new_asoc); |
2203 | break; | |
2204 | ||
2205 | case 'D': /* Collision case D. */ | |
24cb81a6 | 2206 | retval = sctp_sf_do_dupcook_d(net, ep, asoc, chunk, commands, |
1da177e4 LT |
2207 | new_asoc); |
2208 | break; | |
2209 | ||
2210 | default: /* Discard packet for all others. */ | |
24cb81a6 | 2211 | retval = sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2212 | break; |
3ff50b79 | 2213 | } |
1da177e4 LT |
2214 | |
2215 | /* Delete the tempory new association. */ | |
f2815633 | 2216 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC, SCTP_ASOC(new_asoc)); |
1da177e4 LT |
2217 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); |
2218 | ||
d5ccd496 MM |
2219 | /* Restore association pointer to provide SCTP command interpeter |
2220 | * with a valid context in case it needs to manipulate | |
2221 | * the queues */ | |
2222 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_ASOC, | |
2223 | SCTP_ASOC((struct sctp_association *)asoc)); | |
2224 | ||
1da177e4 LT |
2225 | return retval; |
2226 | ||
2227 | nomem: | |
2228 | return SCTP_DISPOSITION_NOMEM; | |
2229 | } | |
2230 | ||
2231 | /* | |
2232 | * Process an ABORT. (SHUTDOWN-PENDING state) | |
2233 | * | |
2234 | * See sctp_sf_do_9_1_abort(). | |
2235 | */ | |
172a1599 XL |
2236 | enum sctp_disposition sctp_sf_shutdown_pending_abort( |
2237 | struct net *net, | |
2238 | const struct sctp_endpoint *ep, | |
2239 | const struct sctp_association *asoc, | |
2240 | const union sctp_subtype type, | |
2241 | void *arg, | |
2242 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
2243 | { |
2244 | struct sctp_chunk *chunk = arg; | |
2245 | ||
2246 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2247 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2248 | |
2249 | /* Make sure that the ABORT chunk has a valid length. | |
2250 | * Since this is an ABORT chunk, we have to discard it | |
2251 | * because of the following text: | |
2252 | * RFC 2960, Section 3.3.7 | |
2253 | * If an endpoint receives an ABORT with a format error or for an | |
2254 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2255 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2256 | * as we do not know its true length. So, to be safe, discard the |
2257 | * packet. | |
2258 | */ | |
441ae65a | 2259 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_abort_chunk))) |
24cb81a6 | 2260 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2261 | |
75205f47 VY |
2262 | /* ADD-IP: Special case for ABORT chunks |
2263 | * F4) One special consideration is that ABORT Chunks arriving | |
2264 | * destined to the IP address being deleted MUST be | |
2265 | * ignored (see Section 5.3.1 for further details). | |
2266 | */ | |
2267 | if (SCTP_ADDR_DEL == | |
2268 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2269 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2270 | |
24cb81a6 | 2271 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2272 | } |
2273 | ||
2274 | /* | |
2275 | * Process an ABORT. (SHUTDOWN-SENT state) | |
2276 | * | |
2277 | * See sctp_sf_do_9_1_abort(). | |
2278 | */ | |
172a1599 XL |
2279 | enum sctp_disposition sctp_sf_shutdown_sent_abort( |
2280 | struct net *net, | |
24cb81a6 | 2281 | const struct sctp_endpoint *ep, |
1da177e4 | 2282 | const struct sctp_association *asoc, |
bfc6f827 | 2283 | const union sctp_subtype type, |
1da177e4 | 2284 | void *arg, |
a85bbeb2 | 2285 | struct sctp_cmd_seq *commands) |
1da177e4 LT |
2286 | { |
2287 | struct sctp_chunk *chunk = arg; | |
2288 | ||
2289 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2290 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2291 | |
2292 | /* Make sure that the ABORT chunk has a valid length. | |
2293 | * Since this is an ABORT chunk, we have to discard it | |
2294 | * because of the following text: | |
2295 | * RFC 2960, Section 3.3.7 | |
2296 | * If an endpoint receives an ABORT with a format error or for an | |
2297 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2298 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2299 | * as we do not know its true length. So, to be safe, discard the |
2300 | * packet. | |
2301 | */ | |
441ae65a | 2302 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_abort_chunk))) |
24cb81a6 | 2303 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2304 | |
75205f47 VY |
2305 | /* ADD-IP: Special case for ABORT chunks |
2306 | * F4) One special consideration is that ABORT Chunks arriving | |
2307 | * destined to the IP address being deleted MUST be | |
2308 | * ignored (see Section 5.3.1 for further details). | |
2309 | */ | |
2310 | if (SCTP_ADDR_DEL == | |
2311 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2312 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2313 | |
1da177e4 LT |
2314 | /* Stop the T2-shutdown timer. */ |
2315 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2316 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2317 | ||
2318 | /* Stop the T5-shutdown guard timer. */ | |
2319 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2320 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2321 | ||
24cb81a6 | 2322 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2323 | } |
2324 | ||
2325 | /* | |
2326 | * Process an ABORT. (SHUTDOWN-ACK-SENT state) | |
2327 | * | |
2328 | * See sctp_sf_do_9_1_abort(). | |
2329 | */ | |
172a1599 XL |
2330 | enum sctp_disposition sctp_sf_shutdown_ack_sent_abort( |
2331 | struct net *net, | |
2332 | const struct sctp_endpoint *ep, | |
2333 | const struct sctp_association *asoc, | |
2334 | const union sctp_subtype type, | |
2335 | void *arg, | |
2336 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
2337 | { |
2338 | /* The same T2 timer, so we should be able to use | |
2339 | * common function with the SHUTDOWN-SENT state. | |
2340 | */ | |
24cb81a6 | 2341 | return sctp_sf_shutdown_sent_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2342 | } |
2343 | ||
2344 | /* | |
2345 | * Handle an Error received in COOKIE_ECHOED state. | |
2346 | * | |
2347 | * Only handle the error type of stale COOKIE Error, the other errors will | |
2348 | * be ignored. | |
2349 | * | |
2350 | * Inputs | |
2351 | * (endpoint, asoc, chunk) | |
2352 | * | |
2353 | * Outputs | |
2354 | * (asoc, reply_msg, msg_up, timers, counters) | |
2355 | * | |
2356 | * The return value is the disposition of the chunk. | |
2357 | */ | |
172a1599 XL |
2358 | enum sctp_disposition sctp_sf_cookie_echoed_err( |
2359 | struct net *net, | |
24cb81a6 | 2360 | const struct sctp_endpoint *ep, |
1da177e4 | 2361 | const struct sctp_association *asoc, |
bfc6f827 | 2362 | const union sctp_subtype type, |
1da177e4 | 2363 | void *arg, |
a85bbeb2 | 2364 | struct sctp_cmd_seq *commands) |
1da177e4 LT |
2365 | { |
2366 | struct sctp_chunk *chunk = arg; | |
d8238d9d | 2367 | struct sctp_errhdr *err; |
1da177e4 LT |
2368 | |
2369 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2370 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2371 | |
2372 | /* Make sure that the ERROR chunk has a valid length. | |
2373 | * The parameter walking depends on this as well. | |
2374 | */ | |
87caeba7 | 2375 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_operr_chunk))) |
24cb81a6 | 2376 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2377 | commands); |
2378 | ||
2379 | /* Process the error here */ | |
2380 | /* FUTURE FIXME: When PR-SCTP related and other optional | |
2381 | * parms are emitted, this will have to change to handle multiple | |
2382 | * errors. | |
2383 | */ | |
2384 | sctp_walk_errors(err, chunk->chunk_hdr) { | |
2385 | if (SCTP_ERROR_STALE_COOKIE == err->cause) | |
24cb81a6 | 2386 | return sctp_sf_do_5_2_6_stale(net, ep, asoc, type, |
1da177e4 LT |
2387 | arg, commands); |
2388 | } | |
2389 | ||
2390 | /* It is possible to have malformed error causes, and that | |
2391 | * will cause us to end the walk early. However, since | |
2392 | * we are discarding the packet, there should be no adverse | |
2393 | * affects. | |
2394 | */ | |
24cb81a6 | 2395 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2396 | } |
2397 | ||
2398 | /* | |
2399 | * Handle a Stale COOKIE Error | |
2400 | * | |
2401 | * Section: 5.2.6 Handle Stale COOKIE Error | |
2402 | * If the association is in the COOKIE-ECHOED state, the endpoint may elect | |
2403 | * one of the following three alternatives. | |
2404 | * ... | |
2405 | * 3) Send a new INIT chunk to the endpoint, adding a Cookie | |
2406 | * Preservative parameter requesting an extension to the lifetime of | |
2407 | * the State Cookie. When calculating the time extension, an | |
2408 | * implementation SHOULD use the RTT information measured based on the | |
2409 | * previous COOKIE ECHO / ERROR exchange, and should add no more | |
2410 | * than 1 second beyond the measured RTT, due to long State Cookie | |
2411 | * lifetimes making the endpoint more subject to a replay attack. | |
2412 | * | |
2413 | * Verification Tag: Not explicit, but safe to ignore. | |
2414 | * | |
2415 | * Inputs | |
2416 | * (endpoint, asoc, chunk) | |
2417 | * | |
2418 | * Outputs | |
2419 | * (asoc, reply_msg, msg_up, timers, counters) | |
2420 | * | |
2421 | * The return value is the disposition of the chunk. | |
2422 | */ | |
172a1599 XL |
2423 | static enum sctp_disposition sctp_sf_do_5_2_6_stale( |
2424 | struct net *net, | |
2425 | const struct sctp_endpoint *ep, | |
2426 | const struct sctp_association *asoc, | |
2427 | const union sctp_subtype type, | |
2428 | void *arg, | |
2429 | struct sctp_cmd_seq *commands) | |
1da177e4 | 2430 | { |
3f7a87d2 | 2431 | int attempts = asoc->init_err_counter + 1; |
365ddb65 XL |
2432 | struct sctp_chunk *chunk = arg, *reply; |
2433 | struct sctp_cookie_preserve_param bht; | |
2434 | struct sctp_bind_addr *bp; | |
d8238d9d | 2435 | struct sctp_errhdr *err; |
365ddb65 | 2436 | u32 stale; |
1da177e4 | 2437 | |
81845c21 | 2438 | if (attempts > asoc->max_init_attempts) { |
8de8c873 SS |
2439 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
2440 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 2441 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 2442 | SCTP_PERR(SCTP_ERROR_STALE_COOKIE)); |
1da177e4 LT |
2443 | return SCTP_DISPOSITION_DELETE_TCB; |
2444 | } | |
2445 | ||
d8238d9d | 2446 | err = (struct sctp_errhdr *)(chunk->skb->data); |
1da177e4 LT |
2447 | |
2448 | /* When calculating the time extension, an implementation | |
2449 | * SHOULD use the RTT information measured based on the | |
2450 | * previous COOKIE ECHO / ERROR exchange, and should add no | |
2451 | * more than 1 second beyond the measured RTT, due to long | |
2452 | * State Cookie lifetimes making the endpoint more subject to | |
2453 | * a replay attack. | |
2454 | * Measure of Staleness's unit is usec. (1/1000000 sec) | |
2455 | * Suggested Cookie Life-span Increment's unit is msec. | |
2456 | * (1/1000 sec) | |
2457 | * In general, if you use the suggested cookie life, the value | |
2458 | * found in the field of measure of staleness should be doubled | |
2459 | * to give ample time to retransmit the new cookie and thus | |
2460 | * yield a higher probability of success on the reattempt. | |
2461 | */ | |
d8238d9d | 2462 | stale = ntohl(*(__be32 *)((u8 *)err + sizeof(*err))); |
1da177e4 LT |
2463 | stale = (stale * 2) / 1000; |
2464 | ||
2465 | bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE; | |
2466 | bht.param_hdr.length = htons(sizeof(bht)); | |
2467 | bht.lifespan_increment = htonl(stale); | |
2468 | ||
2469 | /* Build that new INIT chunk. */ | |
2470 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; | |
2471 | reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht)); | |
2472 | if (!reply) | |
2473 | goto nomem; | |
2474 | ||
2475 | sctp_addto_chunk(reply, sizeof(bht), &bht); | |
2476 | ||
2477 | /* Clear peer's init_tag cached in assoc as we are sending a new INIT */ | |
2478 | sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL()); | |
2479 | ||
2480 | /* Stop pending T3-rtx and heartbeat timers */ | |
2481 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); | |
2482 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
2483 | ||
2484 | /* Delete non-primary peer ip addresses since we are transitioning | |
2485 | * back to the COOKIE-WAIT state | |
2486 | */ | |
2487 | sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL()); | |
2488 | ||
d808ad9a YH |
2489 | /* If we've sent any data bundled with COOKIE-ECHO we will need to |
2490 | * resend | |
1da177e4 | 2491 | */ |
b6157d8e | 2492 | sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN, |
1da177e4 LT |
2493 | SCTP_TRANSPORT(asoc->peer.primary_path)); |
2494 | ||
2495 | /* Cast away the const modifier, as we want to just | |
2496 | * rerun it through as a sideffect. | |
2497 | */ | |
3f7a87d2 | 2498 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL()); |
1da177e4 LT |
2499 | |
2500 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2501 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2502 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2503 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
2504 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
2505 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
2506 | ||
2507 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2508 | ||
2509 | return SCTP_DISPOSITION_CONSUME; | |
2510 | ||
2511 | nomem: | |
2512 | return SCTP_DISPOSITION_NOMEM; | |
2513 | } | |
2514 | ||
2515 | /* | |
2516 | * Process an ABORT. | |
2517 | * | |
2518 | * Section: 9.1 | |
2519 | * After checking the Verification Tag, the receiving endpoint shall | |
2520 | * remove the association from its record, and shall report the | |
2521 | * termination to its upper layer. | |
2522 | * | |
2523 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
2524 | * B) Rules for packet carrying ABORT: | |
2525 | * | |
2526 | * - The endpoint shall always fill in the Verification Tag field of the | |
2527 | * outbound packet with the destination endpoint's tag value if it | |
2528 | * is known. | |
2529 | * | |
2530 | * - If the ABORT is sent in response to an OOTB packet, the endpoint | |
2531 | * MUST follow the procedure described in Section 8.4. | |
2532 | * | |
2533 | * - The receiver MUST accept the packet if the Verification Tag | |
2534 | * matches either its own tag, OR the tag of its peer. Otherwise, the | |
2535 | * receiver MUST silently discard the packet and take no further | |
2536 | * action. | |
2537 | * | |
2538 | * Inputs | |
2539 | * (endpoint, asoc, chunk) | |
2540 | * | |
2541 | * Outputs | |
2542 | * (asoc, reply_msg, msg_up, timers, counters) | |
2543 | * | |
2544 | * The return value is the disposition of the chunk. | |
2545 | */ | |
172a1599 XL |
2546 | enum sctp_disposition sctp_sf_do_9_1_abort( |
2547 | struct net *net, | |
24cb81a6 | 2548 | const struct sctp_endpoint *ep, |
1da177e4 | 2549 | const struct sctp_association *asoc, |
bfc6f827 | 2550 | const union sctp_subtype type, |
1da177e4 | 2551 | void *arg, |
a85bbeb2 | 2552 | struct sctp_cmd_seq *commands) |
1da177e4 LT |
2553 | { |
2554 | struct sctp_chunk *chunk = arg; | |
1da177e4 LT |
2555 | |
2556 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2557 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2558 | |
2559 | /* Make sure that the ABORT chunk has a valid length. | |
2560 | * Since this is an ABORT chunk, we have to discard it | |
2561 | * because of the following text: | |
2562 | * RFC 2960, Section 3.3.7 | |
2563 | * If an endpoint receives an ABORT with a format error or for an | |
2564 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2565 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2566 | * as we do not know its true length. So, to be safe, discard the |
2567 | * packet. | |
2568 | */ | |
441ae65a | 2569 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_abort_chunk))) |
24cb81a6 | 2570 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2571 | |
75205f47 VY |
2572 | /* ADD-IP: Special case for ABORT chunks |
2573 | * F4) One special consideration is that ABORT Chunks arriving | |
2574 | * destined to the IP address being deleted MUST be | |
2575 | * ignored (see Section 5.3.1 for further details). | |
2576 | */ | |
2577 | if (SCTP_ADDR_DEL == | |
2578 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
24cb81a6 | 2579 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, commands); |
75205f47 | 2580 | |
24cb81a6 | 2581 | return __sctp_sf_do_9_1_abort(net, ep, asoc, type, arg, commands); |
75205f47 VY |
2582 | } |
2583 | ||
172a1599 XL |
2584 | static enum sctp_disposition __sctp_sf_do_9_1_abort( |
2585 | struct net *net, | |
24cb81a6 | 2586 | const struct sctp_endpoint *ep, |
75205f47 | 2587 | const struct sctp_association *asoc, |
bfc6f827 | 2588 | const union sctp_subtype type, |
75205f47 | 2589 | void *arg, |
a85bbeb2 | 2590 | struct sctp_cmd_seq *commands) |
75205f47 | 2591 | { |
172a1599 | 2592 | __be16 error = SCTP_ERROR_NO_ERROR; |
75205f47 | 2593 | struct sctp_chunk *chunk = arg; |
95c96174 | 2594 | unsigned int len; |
75205f47 | 2595 | |
1da177e4 LT |
2596 | /* See if we have an error cause code in the chunk. */ |
2597 | len = ntohs(chunk->chunk_hdr->length); | |
96ca468b | 2598 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) { |
d8238d9d | 2599 | struct sctp_errhdr *err; |
96ca468b | 2600 | |
96ca468b SW |
2601 | sctp_walk_errors(err, chunk->chunk_hdr); |
2602 | if ((void *)err != (void *)chunk->chunk_end) | |
d8238d9d XL |
2603 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, |
2604 | commands); | |
96ca468b | 2605 | |
d8238d9d | 2606 | error = ((struct sctp_errhdr *)chunk->skb->data)->cause; |
96ca468b | 2607 | } |
1da177e4 | 2608 | |
8de8c873 | 2609 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); |
d808ad9a | 2610 | /* ASSOC_FAILED will DELETE_TCB. */ |
5be291fe | 2611 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error)); |
b01a2407 EB |
2612 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
2613 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
2614 | |
2615 | return SCTP_DISPOSITION_ABORT; | |
2616 | } | |
2617 | ||
2618 | /* | |
2619 | * Process an ABORT. (COOKIE-WAIT state) | |
2620 | * | |
2621 | * See sctp_sf_do_9_1_abort() above. | |
2622 | */ | |
172a1599 XL |
2623 | enum sctp_disposition sctp_sf_cookie_wait_abort( |
2624 | struct net *net, | |
2625 | const struct sctp_endpoint *ep, | |
2626 | const struct sctp_association *asoc, | |
2627 | const union sctp_subtype type, | |
2628 | void *arg, | |
2629 | struct sctp_cmd_seq *commands) | |
1da177e4 | 2630 | { |
172a1599 | 2631 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 | 2632 | struct sctp_chunk *chunk = arg; |
95c96174 | 2633 | unsigned int len; |
1da177e4 LT |
2634 | |
2635 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
24cb81a6 | 2636 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2637 | |
2638 | /* Make sure that the ABORT chunk has a valid length. | |
2639 | * Since this is an ABORT chunk, we have to discard it | |
2640 | * because of the following text: | |
2641 | * RFC 2960, Section 3.3.7 | |
2642 | * If an endpoint receives an ABORT with a format error or for an | |
2643 | * association that doesn't exist, it MUST silently discard it. | |
25985edc | 2644 | * Because the length is "invalid", we can't really discard just |
1da177e4 LT |
2645 | * as we do not know its true length. So, to be safe, discard the |
2646 | * packet. | |
2647 | */ | |
441ae65a | 2648 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_abort_chunk))) |
24cb81a6 | 2649 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2650 | |
2651 | /* See if we have an error cause code in the chunk. */ | |
2652 | len = ntohs(chunk->chunk_hdr->length); | |
2653 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
d8238d9d | 2654 | error = ((struct sctp_errhdr *)chunk->skb->data)->cause; |
1da177e4 | 2655 | |
24cb81a6 | 2656 | return sctp_stop_t1_and_abort(net, commands, error, ECONNREFUSED, asoc, |
8de8c873 | 2657 | chunk->transport); |
1da177e4 LT |
2658 | } |
2659 | ||
2660 | /* | |
2661 | * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state) | |
2662 | */ | |
172a1599 XL |
2663 | enum sctp_disposition sctp_sf_cookie_wait_icmp_abort( |
2664 | struct net *net, | |
24cb81a6 | 2665 | const struct sctp_endpoint *ep, |
1da177e4 | 2666 | const struct sctp_association *asoc, |
bfc6f827 | 2667 | const union sctp_subtype type, |
1da177e4 | 2668 | void *arg, |
a85bbeb2 | 2669 | struct sctp_cmd_seq *commands) |
1da177e4 | 2670 | { |
24cb81a6 | 2671 | return sctp_stop_t1_and_abort(net, commands, SCTP_ERROR_NO_ERROR, |
8de8c873 | 2672 | ENOPROTOOPT, asoc, |
3f7a87d2 | 2673 | (struct sctp_transport *)arg); |
1da177e4 LT |
2674 | } |
2675 | ||
2676 | /* | |
2677 | * Process an ABORT. (COOKIE-ECHOED state) | |
2678 | */ | |
172a1599 XL |
2679 | enum sctp_disposition sctp_sf_cookie_echoed_abort( |
2680 | struct net *net, | |
2681 | const struct sctp_endpoint *ep, | |
2682 | const struct sctp_association *asoc, | |
2683 | const union sctp_subtype type, | |
2684 | void *arg, | |
2685 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
2686 | { |
2687 | /* There is a single T1 timer, so we should be able to use | |
2688 | * common function with the COOKIE-WAIT state. | |
2689 | */ | |
24cb81a6 | 2690 | return sctp_sf_cookie_wait_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2691 | } |
2692 | ||
2693 | /* | |
2694 | * Stop T1 timer and abort association with "INIT failed". | |
2695 | * | |
2696 | * This is common code called by several sctp_sf_*_abort() functions above. | |
2697 | */ | |
172a1599 XL |
2698 | static enum sctp_disposition sctp_stop_t1_and_abort( |
2699 | struct net *net, | |
2700 | struct sctp_cmd_seq *commands, | |
2701 | __be16 error, int sk_err, | |
2702 | const struct sctp_association *asoc, | |
2703 | struct sctp_transport *transport) | |
1da177e4 | 2704 | { |
bb33381d DB |
2705 | pr_debug("%s: ABORT received (INIT)\n", __func__); |
2706 | ||
1da177e4 LT |
2707 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
2708 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
24cb81a6 | 2709 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
1da177e4 LT |
2710 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
2711 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
8de8c873 | 2712 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); |
1da177e4 LT |
2713 | /* CMD_INIT_FAILED will DELETE_TCB. */ |
2714 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 2715 | SCTP_PERR(error)); |
bb33381d | 2716 | |
3f7a87d2 | 2717 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
2718 | } |
2719 | ||
2720 | /* | |
2721 | * sctp_sf_do_9_2_shut | |
2722 | * | |
2723 | * Section: 9.2 | |
2724 | * Upon the reception of the SHUTDOWN, the peer endpoint shall | |
2725 | * - enter the SHUTDOWN-RECEIVED state, | |
2726 | * | |
2727 | * - stop accepting new data from its SCTP user | |
2728 | * | |
2729 | * - verify, by checking the Cumulative TSN Ack field of the chunk, | |
2730 | * that all its outstanding DATA chunks have been received by the | |
2731 | * SHUTDOWN sender. | |
2732 | * | |
2733 | * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT | |
2734 | * send a SHUTDOWN in response to a ULP request. And should discard | |
2735 | * subsequent SHUTDOWN chunks. | |
2736 | * | |
2737 | * If there are still outstanding DATA chunks left, the SHUTDOWN | |
2738 | * receiver shall continue to follow normal data transmission | |
2739 | * procedures defined in Section 6 until all outstanding DATA chunks | |
2740 | * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept | |
2741 | * new data from its SCTP user. | |
2742 | * | |
2743 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2744 | * | |
2745 | * Inputs | |
2746 | * (endpoint, asoc, chunk) | |
2747 | * | |
2748 | * Outputs | |
2749 | * (asoc, reply_msg, msg_up, timers, counters) | |
2750 | * | |
2751 | * The return value is the disposition of the chunk. | |
2752 | */ | |
172a1599 XL |
2753 | enum sctp_disposition sctp_sf_do_9_2_shutdown( |
2754 | struct net *net, | |
2755 | const struct sctp_endpoint *ep, | |
2756 | const struct sctp_association *asoc, | |
2757 | const union sctp_subtype type, | |
2758 | void *arg, | |
2759 | struct sctp_cmd_seq *commands) | |
2760 | { | |
2761 | enum sctp_disposition disposition; | |
1da177e4 | 2762 | struct sctp_chunk *chunk = arg; |
e61e4055 | 2763 | struct sctp_shutdownhdr *sdh; |
1da177e4 | 2764 | struct sctp_ulpevent *ev; |
df10eec4 | 2765 | __u32 ctsn; |
1da177e4 LT |
2766 | |
2767 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2768 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
2769 | |
2770 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
ac23e681 | 2771 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk))) |
24cb81a6 | 2772 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
2773 | commands); |
2774 | ||
2775 | /* Convert the elaborate header. */ | |
e61e4055 XL |
2776 | sdh = (struct sctp_shutdownhdr *)chunk->skb->data; |
2777 | skb_pull(chunk->skb, sizeof(*sdh)); | |
1da177e4 | 2778 | chunk->subh.shutdown_hdr = sdh; |
df10eec4 WY |
2779 | ctsn = ntohl(sdh->cum_tsn_ack); |
2780 | ||
a2f36eec | 2781 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { |
bb33381d DB |
2782 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
2783 | asoc->ctsn_ack_point); | |
2784 | ||
a2f36eec WY |
2785 | return SCTP_DISPOSITION_DISCARD; |
2786 | } | |
2787 | ||
df10eec4 WY |
2788 | /* If Cumulative TSN Ack beyond the max tsn currently |
2789 | * send, terminating the association and respond to the | |
2790 | * sender with an ABORT. | |
2791 | */ | |
2792 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
24cb81a6 | 2793 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
1da177e4 | 2794 | |
eb0e0076 SS |
2795 | /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT |
2796 | * When a peer sends a SHUTDOWN, SCTP delivers this notification to | |
2797 | * inform the application that it should cease sending data. | |
2798 | */ | |
2799 | ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC); | |
2800 | if (!ev) { | |
2801 | disposition = SCTP_DISPOSITION_NOMEM; | |
d808ad9a | 2802 | goto out; |
eb0e0076 SS |
2803 | } |
2804 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
2805 | ||
1da177e4 LT |
2806 | /* Upon the reception of the SHUTDOWN, the peer endpoint shall |
2807 | * - enter the SHUTDOWN-RECEIVED state, | |
2808 | * - stop accepting new data from its SCTP user | |
2809 | * | |
2810 | * [This is implicit in the new state.] | |
2811 | */ | |
2812 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2813 | SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED)); | |
2814 | disposition = SCTP_DISPOSITION_CONSUME; | |
2815 | ||
2816 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 2817 | disposition = sctp_sf_do_9_2_shutdown_ack(net, ep, asoc, type, |
1da177e4 LT |
2818 | arg, commands); |
2819 | } | |
2820 | ||
2821 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
2822 | goto out; | |
2823 | ||
2824 | /* - verify, by checking the Cumulative TSN Ack field of the | |
2825 | * chunk, that all its outstanding DATA chunks have been | |
2826 | * received by the SHUTDOWN sender. | |
2827 | */ | |
2828 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2178eda8 | 2829 | SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack)); |
1da177e4 | 2830 | |
1da177e4 LT |
2831 | out: |
2832 | return disposition; | |
2833 | } | |
2834 | ||
2e3f92da WY |
2835 | /* |
2836 | * sctp_sf_do_9_2_shut_ctsn | |
2837 | * | |
2838 | * Once an endpoint has reached the SHUTDOWN-RECEIVED state, | |
2839 | * it MUST NOT send a SHUTDOWN in response to a ULP request. | |
2840 | * The Cumulative TSN Ack of the received SHUTDOWN chunk | |
2841 | * MUST be processed. | |
2842 | */ | |
172a1599 XL |
2843 | enum sctp_disposition sctp_sf_do_9_2_shut_ctsn( |
2844 | struct net *net, | |
2845 | const struct sctp_endpoint *ep, | |
2846 | const struct sctp_association *asoc, | |
2847 | const union sctp_subtype type, | |
2848 | void *arg, | |
2849 | struct sctp_cmd_seq *commands) | |
2e3f92da WY |
2850 | { |
2851 | struct sctp_chunk *chunk = arg; | |
e61e4055 | 2852 | struct sctp_shutdownhdr *sdh; |
a2f36eec | 2853 | __u32 ctsn; |
2e3f92da WY |
2854 | |
2855 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2856 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
2e3f92da WY |
2857 | |
2858 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
ac23e681 | 2859 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk))) |
24cb81a6 | 2860 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
2e3f92da WY |
2861 | commands); |
2862 | ||
e61e4055 | 2863 | sdh = (struct sctp_shutdownhdr *)chunk->skb->data; |
a2f36eec WY |
2864 | ctsn = ntohl(sdh->cum_tsn_ack); |
2865 | ||
2866 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
bb33381d DB |
2867 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
2868 | asoc->ctsn_ack_point); | |
2869 | ||
a2f36eec WY |
2870 | return SCTP_DISPOSITION_DISCARD; |
2871 | } | |
2e3f92da WY |
2872 | |
2873 | /* If Cumulative TSN Ack beyond the max tsn currently | |
2874 | * send, terminating the association and respond to the | |
2875 | * sender with an ABORT. | |
2876 | */ | |
a2f36eec | 2877 | if (!TSN_lt(ctsn, asoc->next_tsn)) |
24cb81a6 | 2878 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
2e3f92da WY |
2879 | |
2880 | /* verify, by checking the Cumulative TSN Ack field of the | |
2881 | * chunk, that all its outstanding DATA chunks have been | |
2882 | * received by the SHUTDOWN sender. | |
2883 | */ | |
2884 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2885 | SCTP_BE32(sdh->cum_tsn_ack)); | |
2886 | ||
2887 | return SCTP_DISPOSITION_CONSUME; | |
2888 | } | |
2889 | ||
1da177e4 LT |
2890 | /* RFC 2960 9.2 |
2891 | * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk | |
2892 | * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination | |
2893 | * transport addresses (either in the IP addresses or in the INIT chunk) | |
2894 | * that belong to this association, it should discard the INIT chunk and | |
2895 | * retransmit the SHUTDOWN ACK chunk. | |
2896 | */ | |
172a1599 XL |
2897 | enum sctp_disposition sctp_sf_do_9_2_reshutack( |
2898 | struct net *net, | |
2899 | const struct sctp_endpoint *ep, | |
2900 | const struct sctp_association *asoc, | |
2901 | const union sctp_subtype type, | |
2902 | void *arg, | |
2903 | struct sctp_cmd_seq *commands) | |
1da177e4 | 2904 | { |
172a1599 | 2905 | struct sctp_chunk *chunk = arg; |
1da177e4 LT |
2906 | struct sctp_chunk *reply; |
2907 | ||
ece25dfa | 2908 | /* Make sure that the chunk has a valid length */ |
922dbc5b | 2909 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 2910 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
2911 | commands); |
2912 | ||
1da177e4 LT |
2913 | /* Since we are not going to really process this INIT, there |
2914 | * is no point in verifying chunk boundries. Just generate | |
2915 | * the SHUTDOWN ACK. | |
2916 | */ | |
2917 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
2918 | if (NULL == reply) | |
2919 | goto nomem; | |
2920 | ||
2921 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
2922 | * the T2-SHUTDOWN timer. | |
2923 | */ | |
2924 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
2925 | ||
2926 | /* and restart the T2-shutdown timer. */ | |
2927 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2928 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2929 | ||
2930 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2931 | ||
2932 | return SCTP_DISPOSITION_CONSUME; | |
2933 | nomem: | |
2934 | return SCTP_DISPOSITION_NOMEM; | |
2935 | } | |
2936 | ||
2937 | /* | |
2938 | * sctp_sf_do_ecn_cwr | |
2939 | * | |
2940 | * Section: Appendix A: Explicit Congestion Notification | |
2941 | * | |
2942 | * CWR: | |
2943 | * | |
2944 | * RFC 2481 details a specific bit for a sender to send in the header of | |
2945 | * its next outbound TCP segment to indicate to its peer that it has | |
2946 | * reduced its congestion window. This is termed the CWR bit. For | |
2947 | * SCTP the same indication is made by including the CWR chunk. | |
2948 | * This chunk contains one data element, i.e. the TSN number that | |
2949 | * was sent in the ECNE chunk. This element represents the lowest | |
2950 | * TSN number in the datagram that was originally marked with the | |
2951 | * CE bit. | |
2952 | * | |
2953 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2954 | * Inputs | |
2955 | * (endpoint, asoc, chunk) | |
2956 | * | |
2957 | * Outputs | |
2958 | * (asoc, reply_msg, msg_up, timers, counters) | |
2959 | * | |
2960 | * The return value is the disposition of the chunk. | |
2961 | */ | |
172a1599 XL |
2962 | enum sctp_disposition sctp_sf_do_ecn_cwr(struct net *net, |
2963 | const struct sctp_endpoint *ep, | |
2964 | const struct sctp_association *asoc, | |
2965 | const union sctp_subtype type, | |
2966 | void *arg, | |
2967 | struct sctp_cmd_seq *commands) | |
1da177e4 | 2968 | { |
1da177e4 | 2969 | struct sctp_chunk *chunk = arg; |
65f77105 | 2970 | struct sctp_cwrhdr *cwr; |
34bcca28 | 2971 | u32 lowest_tsn; |
1da177e4 LT |
2972 | |
2973 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 2974 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 2975 | |
b515fd27 | 2976 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_ecne_chunk))) |
24cb81a6 | 2977 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 2978 | commands); |
d808ad9a | 2979 | |
65f77105 XL |
2980 | cwr = (struct sctp_cwrhdr *)chunk->skb->data; |
2981 | skb_pull(chunk->skb, sizeof(*cwr)); | |
1da177e4 | 2982 | |
34bcca28 | 2983 | lowest_tsn = ntohl(cwr->lowest_tsn); |
1da177e4 LT |
2984 | |
2985 | /* Does this CWR ack the last sent congestion notification? */ | |
34bcca28 | 2986 | if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) { |
1da177e4 LT |
2987 | /* Stop sending ECNE. */ |
2988 | sctp_add_cmd_sf(commands, | |
2989 | SCTP_CMD_ECN_CWR, | |
34bcca28 | 2990 | SCTP_U32(lowest_tsn)); |
1da177e4 LT |
2991 | } |
2992 | return SCTP_DISPOSITION_CONSUME; | |
2993 | } | |
2994 | ||
2995 | /* | |
2996 | * sctp_sf_do_ecne | |
2997 | * | |
2998 | * Section: Appendix A: Explicit Congestion Notification | |
2999 | * | |
3000 | * ECN-Echo | |
3001 | * | |
3002 | * RFC 2481 details a specific bit for a receiver to send back in its | |
3003 | * TCP acknowledgements to notify the sender of the Congestion | |
3004 | * Experienced (CE) bit having arrived from the network. For SCTP this | |
3005 | * same indication is made by including the ECNE chunk. This chunk | |
3006 | * contains one data element, i.e. the lowest TSN associated with the IP | |
3007 | * datagram marked with the CE bit..... | |
3008 | * | |
3009 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3010 | * Inputs | |
3011 | * (endpoint, asoc, chunk) | |
3012 | * | |
3013 | * Outputs | |
3014 | * (asoc, reply_msg, msg_up, timers, counters) | |
3015 | * | |
3016 | * The return value is the disposition of the chunk. | |
3017 | */ | |
172a1599 XL |
3018 | enum sctp_disposition sctp_sf_do_ecne(struct net *net, |
3019 | const struct sctp_endpoint *ep, | |
3020 | const struct sctp_association *asoc, | |
3021 | const union sctp_subtype type, | |
3022 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 | 3023 | { |
1da177e4 | 3024 | struct sctp_chunk *chunk = arg; |
1fb6d83b | 3025 | struct sctp_ecnehdr *ecne; |
1da177e4 LT |
3026 | |
3027 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3028 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 3029 | |
b515fd27 | 3030 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_ecne_chunk))) |
24cb81a6 | 3031 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3032 | commands); |
3033 | ||
1fb6d83b XL |
3034 | ecne = (struct sctp_ecnehdr *)chunk->skb->data; |
3035 | skb_pull(chunk->skb, sizeof(*ecne)); | |
1da177e4 LT |
3036 | |
3037 | /* If this is a newer ECNE than the last CWR packet we sent out */ | |
3038 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE, | |
3039 | SCTP_U32(ntohl(ecne->lowest_tsn))); | |
3040 | ||
3041 | return SCTP_DISPOSITION_CONSUME; | |
3042 | } | |
3043 | ||
3044 | /* | |
3045 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
3046 | * | |
3047 | * The SCTP endpoint MUST always acknowledge the reception of each valid | |
3048 | * DATA chunk. | |
3049 | * | |
3050 | * The guidelines on delayed acknowledgement algorithm specified in | |
3051 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
3052 | * acknowledgement SHOULD be generated for at least every second packet | |
3053 | * (not every second DATA chunk) received, and SHOULD be generated within | |
3054 | * 200 ms of the arrival of any unacknowledged DATA chunk. In some | |
3055 | * situations it may be beneficial for an SCTP transmitter to be more | |
3056 | * conservative than the algorithms detailed in this document allow. | |
3057 | * However, an SCTP transmitter MUST NOT be more aggressive than the | |
3058 | * following algorithms allow. | |
3059 | * | |
3060 | * A SCTP receiver MUST NOT generate more than one SACK for every | |
3061 | * incoming packet, other than to update the offered window as the | |
3062 | * receiving application consumes new data. | |
3063 | * | |
3064 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3065 | * | |
3066 | * Inputs | |
3067 | * (endpoint, asoc, chunk) | |
3068 | * | |
3069 | * Outputs | |
3070 | * (asoc, reply_msg, msg_up, timers, counters) | |
3071 | * | |
3072 | * The return value is the disposition of the chunk. | |
3073 | */ | |
172a1599 XL |
3074 | enum sctp_disposition sctp_sf_eat_data_6_2(struct net *net, |
3075 | const struct sctp_endpoint *ep, | |
3076 | const struct sctp_association *asoc, | |
3077 | const union sctp_subtype type, | |
3078 | void *arg, | |
3079 | struct sctp_cmd_seq *commands) | |
1da177e4 | 3080 | { |
c488b770 | 3081 | union sctp_arg force = SCTP_NOFORCE(); |
1da177e4 LT |
3082 | struct sctp_chunk *chunk = arg; |
3083 | int error; | |
3084 | ||
3085 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3086 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3087 | SCTP_NULL()); | |
24cb81a6 | 3088 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
d808ad9a | 3089 | } |
1da177e4 | 3090 | |
9d4ceaf1 | 3091 | if (!sctp_chunk_length_valid(chunk, sctp_datachk_len(&asoc->stream))) |
24cb81a6 | 3092 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3093 | commands); |
3094 | ||
cb3f837b | 3095 | error = sctp_eat_data(asoc, chunk, commands); |
1da177e4 LT |
3096 | switch (error) { |
3097 | case SCTP_IERROR_NO_ERROR: | |
3098 | break; | |
3099 | case SCTP_IERROR_HIGH_TSN: | |
3100 | case SCTP_IERROR_BAD_STREAM: | |
24cb81a6 | 3101 | SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
3102 | goto discard_noforce; |
3103 | case SCTP_IERROR_DUP_TSN: | |
3104 | case SCTP_IERROR_IGNORE_TSN: | |
24cb81a6 | 3105 | SCTP_INC_STATS(net, SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
3106 | goto discard_force; |
3107 | case SCTP_IERROR_NO_DATA: | |
649621e3 | 3108 | return SCTP_DISPOSITION_ABORT; |
f1751c57 | 3109 | case SCTP_IERROR_PROTO_VIOLATION: |
24cb81a6 | 3110 | return sctp_sf_abort_violation(net, ep, asoc, chunk, commands, |
3583df1a | 3111 | (u8 *)chunk->subh.data_hdr, |
9d4ceaf1 | 3112 | sctp_datahdr_len(&asoc->stream)); |
1da177e4 LT |
3113 | default: |
3114 | BUG(); | |
3115 | } | |
3116 | ||
6dc7694f WY |
3117 | if (chunk->chunk_hdr->flags & SCTP_DATA_SACK_IMM) |
3118 | force = SCTP_FORCE(); | |
3119 | ||
9f70f46b | 3120 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) { |
1da177e4 LT |
3121 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
3122 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
3123 | } | |
3124 | ||
3125 | /* If this is the last chunk in a packet, we need to count it | |
3126 | * toward sack generation. Note that we need to SACK every | |
3127 | * OTHER packet containing data chunks, EVEN IF WE DISCARD | |
3128 | * THEM. We elect to NOT generate SACK's if the chunk fails | |
3129 | * the verification tag test. | |
3130 | * | |
3131 | * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
3132 | * | |
3133 | * The SCTP endpoint MUST always acknowledge the reception of | |
3134 | * each valid DATA chunk. | |
3135 | * | |
3136 | * The guidelines on delayed acknowledgement algorithm | |
3137 | * specified in Section 4.2 of [RFC2581] SHOULD be followed. | |
3138 | * Specifically, an acknowledgement SHOULD be generated for at | |
3139 | * least every second packet (not every second DATA chunk) | |
3140 | * received, and SHOULD be generated within 200 ms of the | |
3141 | * arrival of any unacknowledged DATA chunk. In some | |
3142 | * situations it may be beneficial for an SCTP transmitter to | |
3143 | * be more conservative than the algorithms detailed in this | |
3144 | * document allow. However, an SCTP transmitter MUST NOT be | |
3145 | * more aggressive than the following algorithms allow. | |
3146 | */ | |
52ccb8e9 | 3147 | if (chunk->end_of_packet) |
6dc7694f | 3148 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 3149 | |
1da177e4 LT |
3150 | return SCTP_DISPOSITION_CONSUME; |
3151 | ||
3152 | discard_force: | |
3153 | /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
3154 | * | |
3155 | * When a packet arrives with duplicate DATA chunk(s) and with | |
3156 | * no new DATA chunk(s), the endpoint MUST immediately send a | |
3157 | * SACK with no delay. If a packet arrives with duplicate | |
3158 | * DATA chunk(s) bundled with new DATA chunks, the endpoint | |
3159 | * MAY immediately send a SACK. Normally receipt of duplicate | |
3160 | * DATA chunks will occur when the original SACK chunk was lost | |
3161 | * and the peer's RTO has expired. The duplicate TSN number(s) | |
3162 | * SHOULD be reported in the SACK as duplicate. | |
3163 | */ | |
3164 | /* In our case, we split the MAY SACK advice up whether or not | |
3165 | * the last chunk is a duplicate.' | |
3166 | */ | |
3167 | if (chunk->end_of_packet) | |
3168 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3169 | return SCTP_DISPOSITION_DISCARD; | |
3170 | ||
3171 | discard_noforce: | |
52ccb8e9 | 3172 | if (chunk->end_of_packet) |
6dc7694f | 3173 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 3174 | |
1da177e4 | 3175 | return SCTP_DISPOSITION_DISCARD; |
1da177e4 LT |
3176 | } |
3177 | ||
3178 | /* | |
3179 | * sctp_sf_eat_data_fast_4_4 | |
3180 | * | |
3181 | * Section: 4 (4) | |
3182 | * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received | |
3183 | * DATA chunks without delay. | |
3184 | * | |
3185 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3186 | * Inputs | |
3187 | * (endpoint, asoc, chunk) | |
3188 | * | |
3189 | * Outputs | |
3190 | * (asoc, reply_msg, msg_up, timers, counters) | |
3191 | * | |
3192 | * The return value is the disposition of the chunk. | |
3193 | */ | |
172a1599 XL |
3194 | enum sctp_disposition sctp_sf_eat_data_fast_4_4( |
3195 | struct net *net, | |
3196 | const struct sctp_endpoint *ep, | |
3197 | const struct sctp_association *asoc, | |
3198 | const union sctp_subtype type, | |
3199 | void *arg, | |
3200 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3201 | { |
3202 | struct sctp_chunk *chunk = arg; | |
3203 | int error; | |
3204 | ||
3205 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3206 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3207 | SCTP_NULL()); | |
24cb81a6 | 3208 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3209 | } |
3210 | ||
9d4ceaf1 | 3211 | if (!sctp_chunk_length_valid(chunk, sctp_datachk_len(&asoc->stream))) |
24cb81a6 | 3212 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3213 | commands); |
3214 | ||
cb3f837b | 3215 | error = sctp_eat_data(asoc, chunk, commands); |
1da177e4 LT |
3216 | switch (error) { |
3217 | case SCTP_IERROR_NO_ERROR: | |
3218 | case SCTP_IERROR_HIGH_TSN: | |
3219 | case SCTP_IERROR_DUP_TSN: | |
3220 | case SCTP_IERROR_IGNORE_TSN: | |
3221 | case SCTP_IERROR_BAD_STREAM: | |
3222 | break; | |
3223 | case SCTP_IERROR_NO_DATA: | |
649621e3 | 3224 | return SCTP_DISPOSITION_ABORT; |
f1751c57 | 3225 | case SCTP_IERROR_PROTO_VIOLATION: |
24cb81a6 | 3226 | return sctp_sf_abort_violation(net, ep, asoc, chunk, commands, |
3583df1a | 3227 | (u8 *)chunk->subh.data_hdr, |
9d4ceaf1 | 3228 | sctp_datahdr_len(&asoc->stream)); |
1da177e4 LT |
3229 | default: |
3230 | BUG(); | |
3231 | } | |
3232 | ||
3233 | /* Go a head and force a SACK, since we are shutting down. */ | |
3234 | ||
3235 | /* Implementor's Guide. | |
3236 | * | |
3237 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3238 | * respond to each received packet containing one or more DATA chunk(s) | |
3239 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3240 | */ | |
3241 | if (chunk->end_of_packet) { | |
3242 | /* We must delay the chunk creation since the cumulative | |
3243 | * TSN has not been updated yet. | |
3244 | */ | |
3245 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3246 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3247 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3248 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3249 | } | |
3250 | ||
1da177e4 LT |
3251 | return SCTP_DISPOSITION_CONSUME; |
3252 | } | |
3253 | ||
3254 | /* | |
3255 | * Section: 6.2 Processing a Received SACK | |
3256 | * D) Any time a SACK arrives, the endpoint performs the following: | |
3257 | * | |
3258 | * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point, | |
3259 | * then drop the SACK. Since Cumulative TSN Ack is monotonically | |
3260 | * increasing, a SACK whose Cumulative TSN Ack is less than the | |
3261 | * Cumulative TSN Ack Point indicates an out-of-order SACK. | |
3262 | * | |
3263 | * ii) Set rwnd equal to the newly received a_rwnd minus the number | |
3264 | * of bytes still outstanding after processing the Cumulative TSN Ack | |
3265 | * and the Gap Ack Blocks. | |
3266 | * | |
3267 | * iii) If the SACK is missing a TSN that was previously | |
3268 | * acknowledged via a Gap Ack Block (e.g., the data receiver | |
3269 | * reneged on the data), then mark the corresponding DATA chunk | |
3270 | * as available for retransmit: Mark it as missing for fast | |
3271 | * retransmit as described in Section 7.2.4 and if no retransmit | |
3272 | * timer is running for the destination address to which the DATA | |
3273 | * chunk was originally transmitted, then T3-rtx is started for | |
3274 | * that destination address. | |
3275 | * | |
3276 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3277 | * | |
3278 | * Inputs | |
3279 | * (endpoint, asoc, chunk) | |
3280 | * | |
3281 | * Outputs | |
3282 | * (asoc, reply_msg, msg_up, timers, counters) | |
3283 | * | |
3284 | * The return value is the disposition of the chunk. | |
3285 | */ | |
172a1599 XL |
3286 | enum sctp_disposition sctp_sf_eat_sack_6_2(struct net *net, |
3287 | const struct sctp_endpoint *ep, | |
3288 | const struct sctp_association *asoc, | |
3289 | const union sctp_subtype type, | |
3290 | void *arg, | |
3291 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3292 | { |
3293 | struct sctp_chunk *chunk = arg; | |
78731085 | 3294 | struct sctp_sackhdr *sackh; |
1da177e4 LT |
3295 | __u32 ctsn; |
3296 | ||
103d750c MH |
3297 | trace_sctp_probe(ep, asoc, chunk); |
3298 | ||
1da177e4 | 3299 | if (!sctp_vtag_verify(chunk, asoc)) |
24cb81a6 | 3300 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3301 | |
3302 | /* Make sure that the SACK chunk has a valid length. */ | |
d4d6c614 | 3303 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_sack_chunk))) |
24cb81a6 | 3304 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3305 | commands); |
3306 | ||
3307 | /* Pull the SACK chunk from the data buffer */ | |
3308 | sackh = sctp_sm_pull_sack(chunk); | |
3309 | /* Was this a bogus SACK? */ | |
3310 | if (!sackh) | |
24cb81a6 | 3311 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3312 | chunk->subh.sack_hdr = sackh; |
3313 | ctsn = ntohl(sackh->cum_tsn_ack); | |
3314 | ||
3315 | /* i) If Cumulative TSN Ack is less than the Cumulative TSN | |
3316 | * Ack Point, then drop the SACK. Since Cumulative TSN | |
3317 | * Ack is monotonically increasing, a SACK whose | |
3318 | * Cumulative TSN Ack is less than the Cumulative TSN Ack | |
3319 | * Point indicates an out-of-order SACK. | |
3320 | */ | |
3321 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
bb33381d DB |
3322 | pr_debug("%s: ctsn:%x, ctsn_ack_point:%x\n", __func__, ctsn, |
3323 | asoc->ctsn_ack_point); | |
3324 | ||
1da177e4 LT |
3325 | return SCTP_DISPOSITION_DISCARD; |
3326 | } | |
3327 | ||
aecedeab WY |
3328 | /* If Cumulative TSN Ack beyond the max tsn currently |
3329 | * send, terminating the association and respond to the | |
3330 | * sender with an ABORT. | |
3331 | */ | |
3332 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
24cb81a6 | 3333 | return sctp_sf_violation_ctsn(net, ep, asoc, type, arg, commands); |
aecedeab | 3334 | |
1da177e4 | 3335 | /* Return this SACK for further processing. */ |
edfee033 | 3336 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_CHUNK(chunk)); |
1da177e4 LT |
3337 | |
3338 | /* Note: We do the rest of the work on the PROCESS_SACK | |
3339 | * sideeffect. | |
3340 | */ | |
3341 | return SCTP_DISPOSITION_CONSUME; | |
3342 | } | |
3343 | ||
3344 | /* | |
3345 | * Generate an ABORT in response to a packet. | |
3346 | * | |
047a2428 | 3347 | * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41 |
1da177e4 | 3348 | * |
047a2428 JF |
3349 | * 8) The receiver should respond to the sender of the OOTB packet with |
3350 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3351 | * MUST fill in the Verification Tag field of the outbound packet | |
3352 | * with the value found in the Verification Tag field of the OOTB | |
3353 | * packet and set the T-bit in the Chunk Flags to indicate that the | |
3354 | * Verification Tag is reflected. After sending this ABORT, the | |
3355 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3356 | * no further action. | |
1da177e4 LT |
3357 | * |
3358 | * Verification Tag: | |
3359 | * | |
3360 | * The return value is the disposition of the chunk. | |
3361 | */ | |
172a1599 XL |
3362 | static enum sctp_disposition sctp_sf_tabort_8_4_8( |
3363 | struct net *net, | |
24cb81a6 | 3364 | const struct sctp_endpoint *ep, |
1da177e4 | 3365 | const struct sctp_association *asoc, |
bfc6f827 | 3366 | const union sctp_subtype type, |
1da177e4 | 3367 | void *arg, |
a85bbeb2 | 3368 | struct sctp_cmd_seq *commands) |
1da177e4 LT |
3369 | { |
3370 | struct sctp_packet *packet = NULL; | |
3371 | struct sctp_chunk *chunk = arg; | |
3372 | struct sctp_chunk *abort; | |
3373 | ||
2ce95503 | 3374 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
eab59075 MRL |
3375 | if (!packet) |
3376 | return SCTP_DISPOSITION_NOMEM; | |
1da177e4 | 3377 | |
eab59075 MRL |
3378 | /* Make an ABORT. The T bit will be set if the asoc |
3379 | * is NULL. | |
3380 | */ | |
3381 | abort = sctp_make_abort(asoc, chunk, 0); | |
3382 | if (!abort) { | |
3383 | sctp_ootb_pkt_free(packet); | |
3384 | return SCTP_DISPOSITION_NOMEM; | |
3385 | } | |
047a2428 | 3386 | |
eab59075 MRL |
3387 | /* Reflect vtag if T-Bit is set */ |
3388 | if (sctp_test_T_bit(abort)) | |
3389 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
1da177e4 | 3390 | |
eab59075 MRL |
3391 | /* Set the skb to the belonging sock for accounting. */ |
3392 | abort->skb->sk = ep->base.sk; | |
1da177e4 | 3393 | |
eab59075 | 3394 | sctp_packet_append_chunk(packet, abort); |
1da177e4 | 3395 | |
eab59075 MRL |
3396 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, |
3397 | SCTP_PACKET(packet)); | |
1da177e4 | 3398 | |
eab59075 | 3399 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 | 3400 | |
eab59075 MRL |
3401 | sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
3402 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
3403 | } |
3404 | ||
3405 | /* | |
3406 | * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR | |
3407 | * event as ULP notification for each cause included in the chunk. | |
3408 | * | |
3409 | * API 5.3.1.3 - SCTP_REMOTE_ERROR | |
3410 | * | |
3411 | * The return value is the disposition of the chunk. | |
3412 | */ | |
172a1599 XL |
3413 | enum sctp_disposition sctp_sf_operr_notify(struct net *net, |
3414 | const struct sctp_endpoint *ep, | |
3415 | const struct sctp_association *asoc, | |
3416 | const union sctp_subtype type, | |
3417 | void *arg, | |
3418 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3419 | { |
3420 | struct sctp_chunk *chunk = arg; | |
d8238d9d | 3421 | struct sctp_errhdr *err; |
1da177e4 LT |
3422 | |
3423 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3424 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3425 | |
3426 | /* Make sure that the ERROR chunk has a valid length. */ | |
87caeba7 | 3427 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_operr_chunk))) |
24cb81a6 | 3428 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 3429 | commands); |
8a00be1c SW |
3430 | sctp_walk_errors(err, chunk->chunk_hdr); |
3431 | if ((void *)err != (void *)chunk->chunk_end) | |
24cb81a6 | 3432 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
8a00be1c | 3433 | (void *)err, commands); |
1da177e4 | 3434 | |
3df26787 WY |
3435 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR, |
3436 | SCTP_CHUNK(chunk)); | |
1da177e4 | 3437 | |
1da177e4 | 3438 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3439 | } |
3440 | ||
3441 | /* | |
3442 | * Process an inbound SHUTDOWN ACK. | |
3443 | * | |
3444 | * From Section 9.2: | |
3445 | * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3446 | * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its | |
3447 | * peer, and remove all record of the association. | |
3448 | * | |
3449 | * The return value is the disposition. | |
3450 | */ | |
172a1599 XL |
3451 | enum sctp_disposition sctp_sf_do_9_2_final(struct net *net, |
3452 | const struct sctp_endpoint *ep, | |
3453 | const struct sctp_association *asoc, | |
3454 | const union sctp_subtype type, | |
3455 | void *arg, | |
3456 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3457 | { |
3458 | struct sctp_chunk *chunk = arg; | |
3459 | struct sctp_chunk *reply; | |
3460 | struct sctp_ulpevent *ev; | |
3461 | ||
3462 | if (!sctp_vtag_verify(chunk, asoc)) | |
24cb81a6 | 3463 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3464 | |
3465 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
922dbc5b | 3466 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 3467 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 | 3468 | commands); |
1da177e4 LT |
3469 | /* 10.2 H) SHUTDOWN COMPLETE notification |
3470 | * | |
3471 | * When SCTP completes the shutdown procedures (section 9.2) this | |
3472 | * notification is passed to the upper layer. | |
3473 | */ | |
3474 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 3475 | 0, 0, 0, NULL, GFP_ATOMIC); |
1da177e4 LT |
3476 | if (!ev) |
3477 | goto nomem; | |
3478 | ||
df7deeb5 VY |
3479 | /* ...send a SHUTDOWN COMPLETE chunk to its peer, */ |
3480 | reply = sctp_make_shutdown_complete(asoc, chunk); | |
3481 | if (!reply) | |
3482 | goto nomem_chunk; | |
3483 | ||
3484 | /* Do all the commands now (after allocation), so that we | |
3485 | * have consistent state if memory allocation failes | |
3486 | */ | |
1da177e4 LT |
3487 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
3488 | ||
3489 | /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3490 | * stop the T2-shutdown timer, | |
3491 | */ | |
3492 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3493 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3494 | ||
3495 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3496 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
3497 | ||
1da177e4 LT |
3498 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
3499 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
b01a2407 EB |
3500 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
3501 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3502 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); |
3503 | ||
3504 | /* ...and remove all record of the association. */ | |
3505 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
3506 | return SCTP_DISPOSITION_DELETE_TCB; | |
3507 | ||
df7deeb5 VY |
3508 | nomem_chunk: |
3509 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
3510 | nomem: |
3511 | return SCTP_DISPOSITION_NOMEM; | |
3512 | } | |
3513 | ||
3514 | /* | |
047a2428 JF |
3515 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41. |
3516 | * | |
1da177e4 LT |
3517 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
3518 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. | |
3519 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3520 | * packet must fill in the Verification Tag field of the outbound | |
3521 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
047a2428 JF |
3522 | * set the T-bit in the Chunk Flags to indicate that the Verification |
3523 | * Tag is reflected. | |
1da177e4 LT |
3524 | * |
3525 | * 8) The receiver should respond to the sender of the OOTB packet with | |
3526 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3527 | * MUST fill in the Verification Tag field of the outbound packet | |
3528 | * with the value found in the Verification Tag field of the OOTB | |
047a2428 JF |
3529 | * packet and set the T-bit in the Chunk Flags to indicate that the |
3530 | * Verification Tag is reflected. After sending this ABORT, the | |
3531 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3532 | * no further action. | |
1da177e4 | 3533 | */ |
172a1599 XL |
3534 | enum sctp_disposition sctp_sf_ootb(struct net *net, |
3535 | const struct sctp_endpoint *ep, | |
3536 | const struct sctp_association *asoc, | |
3537 | const union sctp_subtype type, | |
3538 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3539 | { |
3540 | struct sctp_chunk *chunk = arg; | |
3541 | struct sk_buff *skb = chunk->skb; | |
922dbc5b | 3542 | struct sctp_chunkhdr *ch; |
d8238d9d | 3543 | struct sctp_errhdr *err; |
85c5ed4e | 3544 | int ootb_cookie_ack = 0; |
172a1599 XL |
3545 | int ootb_shut_ack = 0; |
3546 | __u8 *ch_end; | |
1da177e4 | 3547 | |
b01a2407 | 3548 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
1da177e4 | 3549 | |
922dbc5b | 3550 | ch = (struct sctp_chunkhdr *)chunk->chunk_hdr; |
1da177e4 | 3551 | do { |
ece25dfa | 3552 | /* Report violation if the chunk is less then minimal */ |
922dbc5b | 3553 | if (ntohs(ch->length) < sizeof(*ch)) |
24cb81a6 | 3554 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa | 3555 | commands); |
1da177e4 | 3556 | |
bf911e98 MRL |
3557 | /* Report violation if chunk len overflows */ |
3558 | ch_end = ((__u8 *)ch) + SCTP_PAD4(ntohs(ch->length)); | |
3559 | if (ch_end > skb_tail_pointer(skb)) | |
3560 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, | |
3561 | commands); | |
3562 | ||
ece25dfa VY |
3563 | /* Now that we know we at least have a chunk header, |
3564 | * do things that are type appropriate. | |
3565 | */ | |
1da177e4 LT |
3566 | if (SCTP_CID_SHUTDOWN_ACK == ch->type) |
3567 | ootb_shut_ack = 1; | |
3568 | ||
3569 | /* RFC 2960, Section 3.3.7 | |
3570 | * Moreover, under any circumstances, an endpoint that | |
3571 | * receives an ABORT MUST NOT respond to that ABORT by | |
3572 | * sending an ABORT of its own. | |
3573 | */ | |
3574 | if (SCTP_CID_ABORT == ch->type) | |
24cb81a6 | 3575 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
d808ad9a | 3576 | |
85c5ed4e SW |
3577 | /* RFC 8.4, 7) If the packet contains a "Stale cookie" ERROR |
3578 | * or a COOKIE ACK the SCTP Packet should be silently | |
3579 | * discarded. | |
3580 | */ | |
3581 | ||
3582 | if (SCTP_CID_COOKIE_ACK == ch->type) | |
3583 | ootb_cookie_ack = 1; | |
3584 | ||
3585 | if (SCTP_CID_ERROR == ch->type) { | |
3586 | sctp_walk_errors(err, ch) { | |
3587 | if (SCTP_ERROR_STALE_COOKIE == err->cause) { | |
3588 | ootb_cookie_ack = 1; | |
3589 | break; | |
3590 | } | |
3591 | } | |
3592 | } | |
3593 | ||
922dbc5b | 3594 | ch = (struct sctp_chunkhdr *)ch_end; |
27a884dc | 3595 | } while (ch_end < skb_tail_pointer(skb)); |
1da177e4 LT |
3596 | |
3597 | if (ootb_shut_ack) | |
24cb81a6 | 3598 | return sctp_sf_shut_8_4_5(net, ep, asoc, type, arg, commands); |
85c5ed4e | 3599 | else if (ootb_cookie_ack) |
24cb81a6 | 3600 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 3601 | else |
24cb81a6 | 3602 | return sctp_sf_tabort_8_4_8(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3603 | } |
3604 | ||
3605 | /* | |
3606 | * Handle an "Out of the blue" SHUTDOWN ACK. | |
3607 | * | |
047a2428 JF |
3608 | * Section: 8.4 5, sctpimpguide 2.41. |
3609 | * | |
1da177e4 | 3610 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
047a2428 JF |
3611 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. |
3612 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3613 | * packet must fill in the Verification Tag field of the outbound | |
3614 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
3615 | * set the T-bit in the Chunk Flags to indicate that the Verification | |
3616 | * Tag is reflected. | |
1da177e4 LT |
3617 | * |
3618 | * Inputs | |
3619 | * (endpoint, asoc, type, arg, commands) | |
3620 | * | |
3621 | * Outputs | |
172a1599 | 3622 | * (enum sctp_disposition) |
1da177e4 LT |
3623 | * |
3624 | * The return value is the disposition of the chunk. | |
3625 | */ | |
172a1599 XL |
3626 | static enum sctp_disposition sctp_sf_shut_8_4_5( |
3627 | struct net *net, | |
3628 | const struct sctp_endpoint *ep, | |
3629 | const struct sctp_association *asoc, | |
3630 | const union sctp_subtype type, | |
3631 | void *arg, | |
3632 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
3633 | { |
3634 | struct sctp_packet *packet = NULL; | |
3635 | struct sctp_chunk *chunk = arg; | |
3636 | struct sctp_chunk *shut; | |
3637 | ||
2ce95503 | 3638 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1ff01561 MRL |
3639 | if (!packet) |
3640 | return SCTP_DISPOSITION_NOMEM; | |
1da177e4 | 3641 | |
1ff01561 MRL |
3642 | /* Make an SHUTDOWN_COMPLETE. |
3643 | * The T bit will be set if the asoc is NULL. | |
3644 | */ | |
3645 | shut = sctp_make_shutdown_complete(asoc, chunk); | |
3646 | if (!shut) { | |
3647 | sctp_ootb_pkt_free(packet); | |
3648 | return SCTP_DISPOSITION_NOMEM; | |
3649 | } | |
047a2428 | 3650 | |
1ff01561 MRL |
3651 | /* Reflect vtag if T-Bit is set */ |
3652 | if (sctp_test_T_bit(shut)) | |
3653 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
1da177e4 | 3654 | |
1ff01561 MRL |
3655 | /* Set the skb to the belonging sock for accounting. */ |
3656 | shut->skb->sk = ep->base.sk; | |
1da177e4 | 3657 | |
1ff01561 | 3658 | sctp_packet_append_chunk(packet, shut); |
1da177e4 | 3659 | |
1ff01561 MRL |
3660 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, |
3661 | SCTP_PACKET(packet)); | |
1da177e4 | 3662 | |
1ff01561 | 3663 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 | 3664 | |
1ff01561 MRL |
3665 | /* If the chunk length is invalid, we don't want to process |
3666 | * the reset of the packet. | |
3667 | */ | |
922dbc5b | 3668 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 3669 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 3670 | |
1ff01561 MRL |
3671 | /* We need to discard the rest of the packet to prevent |
3672 | * potential bomming attacks from additional bundled chunks. | |
3673 | * This is documented in SCTP Threats ID. | |
3674 | */ | |
3675 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
1da177e4 LT |
3676 | } |
3677 | ||
3678 | /* | |
3679 | * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state. | |
3680 | * | |
3681 | * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK | |
3682 | * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the | |
3683 | * procedures in section 8.4 SHOULD be followed, in other words it | |
3684 | * should be treated as an Out Of The Blue packet. | |
3685 | * [This means that we do NOT check the Verification Tag on these | |
3686 | * chunks. --piggy ] | |
3687 | * | |
3688 | */ | |
172a1599 XL |
3689 | enum sctp_disposition sctp_sf_do_8_5_1_E_sa(struct net *net, |
3690 | const struct sctp_endpoint *ep, | |
3691 | const struct sctp_association *asoc, | |
3692 | const union sctp_subtype type, | |
3693 | void *arg, | |
3694 | struct sctp_cmd_seq *commands) | |
1da177e4 | 3695 | { |
ece25dfa VY |
3696 | struct sctp_chunk *chunk = arg; |
3697 | ||
3698 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
922dbc5b | 3699 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 3700 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
3701 | commands); |
3702 | ||
1da177e4 LT |
3703 | /* Although we do have an association in this case, it corresponds |
3704 | * to a restarted association. So the packet is treated as an OOTB | |
3705 | * packet and the state function that handles OOTB SHUTDOWN_ACK is | |
3706 | * called with a NULL association. | |
3707 | */ | |
24cb81a6 | 3708 | SCTP_INC_STATS(net, SCTP_MIB_OUTOFBLUES); |
8190f89d | 3709 | |
24cb81a6 | 3710 | return sctp_sf_shut_8_4_5(net, ep, NULL, type, arg, commands); |
1da177e4 LT |
3711 | } |
3712 | ||
3713 | /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */ | |
172a1599 XL |
3714 | enum sctp_disposition sctp_sf_do_asconf(struct net *net, |
3715 | const struct sctp_endpoint *ep, | |
3716 | const struct sctp_association *asoc, | |
3717 | const union sctp_subtype type, | |
3718 | void *arg, | |
3719 | struct sctp_cmd_seq *commands) | |
1da177e4 | 3720 | { |
172a1599 XL |
3721 | struct sctp_paramhdr *err_param = NULL; |
3722 | struct sctp_chunk *asconf_ack = NULL; | |
3723 | struct sctp_chunk *chunk = arg; | |
3724 | struct sctp_addiphdr *hdr; | |
3725 | __u32 serial; | |
1da177e4 LT |
3726 | |
3727 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3728 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3729 | SCTP_NULL()); | |
24cb81a6 | 3730 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3731 | } |
3732 | ||
6afd2e83 VY |
3733 | /* ADD-IP: Section 4.1.1 |
3734 | * This chunk MUST be sent in an authenticated way by using | |
3735 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3736 | * is received unauthenticated it MUST be silently discarded as | |
3737 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3738 | */ | |
e1fc3b14 | 3739 | if (!net->sctp.addip_noauth && !chunk->auth) |
68d75469 XL |
3740 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, |
3741 | commands); | |
6afd2e83 | 3742 | |
1da177e4 | 3743 | /* Make sure that the ASCONF ADDIP chunk has a valid length. */ |
68d75469 | 3744 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_addip_chunk))) |
24cb81a6 | 3745 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3746 | commands); |
3747 | ||
65205cc4 | 3748 | hdr = (struct sctp_addiphdr *)chunk->skb->data; |
1da177e4 LT |
3749 | serial = ntohl(hdr->serial); |
3750 | ||
6f4c618d | 3751 | /* Verify the ASCONF chunk before processing it. */ |
9de7922b | 3752 | if (!sctp_verify_asconf(asoc, chunk, true, &err_param)) |
24cb81a6 | 3753 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
ba016670 | 3754 | (void *)err_param, commands); |
6f4c618d | 3755 | |
a08de64d | 3756 | /* ADDIP 5.2 E1) Compare the value of the serial number to the value |
1da177e4 | 3757 | * the endpoint stored in a new association variable |
d808ad9a | 3758 | * 'Peer-Serial-Number'. |
1da177e4 LT |
3759 | */ |
3760 | if (serial == asoc->peer.addip_serial + 1) { | |
a08de64d VY |
3761 | /* If this is the first instance of ASCONF in the packet, |
3762 | * we can clean our old ASCONF-ACKs. | |
3763 | */ | |
3764 | if (!chunk->has_asconf) | |
3765 | sctp_assoc_clean_asconf_ack_cache(asoc); | |
3766 | ||
3767 | /* ADDIP 5.2 E4) When the Sequence Number matches the next one | |
3768 | * expected, process the ASCONF as described below and after | |
3769 | * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to | |
3770 | * the response packet and cache a copy of it (in the event it | |
3771 | * later needs to be retransmitted). | |
3772 | * | |
3773 | * Essentially, do V1-V5. | |
1da177e4 LT |
3774 | */ |
3775 | asconf_ack = sctp_process_asconf((struct sctp_association *) | |
3776 | asoc, chunk); | |
3777 | if (!asconf_ack) | |
3778 | return SCTP_DISPOSITION_NOMEM; | |
a08de64d VY |
3779 | } else if (serial < asoc->peer.addip_serial + 1) { |
3780 | /* ADDIP 5.2 E2) | |
3781 | * If the value found in the Sequence Number is less than the | |
3782 | * ('Peer- Sequence-Number' + 1), simply skip to the next | |
3783 | * ASCONF, and include in the outbound response packet | |
3784 | * any previously cached ASCONF-ACK response that was | |
3785 | * sent and saved that matches the Sequence Number of the | |
3786 | * ASCONF. Note: It is possible that no cached ASCONF-ACK | |
3787 | * Chunk exists. This will occur when an older ASCONF | |
3788 | * arrives out of order. In such a case, the receiver | |
3789 | * should skip the ASCONF Chunk and not include ASCONF-ACK | |
3790 | * Chunk for that chunk. | |
1da177e4 | 3791 | */ |
a08de64d VY |
3792 | asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial); |
3793 | if (!asconf_ack) | |
1da177e4 | 3794 | return SCTP_DISPOSITION_DISCARD; |
31b02e15 VY |
3795 | |
3796 | /* Reset the transport so that we select the correct one | |
3797 | * this time around. This is to make sure that we don't | |
3798 | * accidentally use a stale transport that's been removed. | |
3799 | */ | |
3800 | asconf_ack->transport = NULL; | |
1da177e4 | 3801 | } else { |
a08de64d | 3802 | /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since |
1da177e4 | 3803 | * it must be either a stale packet or from an attacker. |
d808ad9a | 3804 | */ |
1da177e4 LT |
3805 | return SCTP_DISPOSITION_DISCARD; |
3806 | } | |
3807 | ||
a08de64d VY |
3808 | /* ADDIP 5.2 E6) The destination address of the SCTP packet |
3809 | * containing the ASCONF-ACK Chunks MUST be the source address of | |
3810 | * the SCTP packet that held the ASCONF Chunks. | |
3811 | * | |
3812 | * To do this properly, we'll set the destination address of the chunk | |
3813 | * and at the transmit time, will try look up the transport to use. | |
3814 | * Since ASCONFs may be bundled, the correct transport may not be | |
94e2bd68 | 3815 | * created until we process the entire packet, thus this workaround. |
1da177e4 | 3816 | */ |
a08de64d | 3817 | asconf_ack->dest = chunk->source; |
1da177e4 | 3818 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack)); |
6af29ccc | 3819 | if (asoc->new_transport) { |
f7010e61 | 3820 | sctp_sf_heartbeat(ep, asoc, type, asoc->new_transport, commands); |
6af29ccc MH |
3821 | ((struct sctp_association *)asoc)->new_transport = NULL; |
3822 | } | |
d808ad9a | 3823 | |
1da177e4 LT |
3824 | return SCTP_DISPOSITION_CONSUME; |
3825 | } | |
3826 | ||
fbd01973 XL |
3827 | static enum sctp_disposition sctp_send_next_asconf( |
3828 | struct net *net, | |
3829 | const struct sctp_endpoint *ep, | |
3830 | struct sctp_association *asoc, | |
3831 | const union sctp_subtype type, | |
3832 | struct sctp_cmd_seq *commands) | |
3833 | { | |
3834 | struct sctp_chunk *asconf; | |
3835 | struct list_head *entry; | |
3836 | ||
3837 | if (list_empty(&asoc->addip_chunk_list)) | |
3838 | return SCTP_DISPOSITION_CONSUME; | |
3839 | ||
3840 | entry = asoc->addip_chunk_list.next; | |
3841 | asconf = list_entry(entry, struct sctp_chunk, list); | |
3842 | ||
3843 | list_del_init(entry); | |
3844 | sctp_chunk_hold(asconf); | |
3845 | asoc->addip_last_asconf = asconf; | |
3846 | ||
3847 | return sctp_sf_do_prm_asconf(net, ep, asoc, type, asconf, commands); | |
3848 | } | |
3849 | ||
1da177e4 LT |
3850 | /* |
3851 | * ADDIP Section 4.3 General rules for address manipulation | |
3852 | * When building TLV parameters for the ASCONF Chunk that will add or | |
3853 | * delete IP addresses the D0 to D13 rules should be applied: | |
3854 | */ | |
172a1599 XL |
3855 | enum sctp_disposition sctp_sf_do_asconf_ack(struct net *net, |
3856 | const struct sctp_endpoint *ep, | |
3857 | const struct sctp_association *asoc, | |
3858 | const union sctp_subtype type, | |
3859 | void *arg, | |
3860 | struct sctp_cmd_seq *commands) | |
1da177e4 | 3861 | { |
172a1599 XL |
3862 | struct sctp_chunk *last_asconf = asoc->addip_last_asconf; |
3863 | struct sctp_paramhdr *err_param = NULL; | |
3864 | struct sctp_chunk *asconf_ack = arg; | |
3865 | struct sctp_addiphdr *addip_hdr; | |
3866 | __u32 sent_serial, rcvd_serial; | |
3867 | struct sctp_chunk *abort; | |
1da177e4 LT |
3868 | |
3869 | if (!sctp_vtag_verify(asconf_ack, asoc)) { | |
3870 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3871 | SCTP_NULL()); | |
24cb81a6 | 3872 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
3873 | } |
3874 | ||
6afd2e83 VY |
3875 | /* ADD-IP, Section 4.1.2: |
3876 | * This chunk MUST be sent in an authenticated way by using | |
3877 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3878 | * is received unauthenticated it MUST be silently discarded as | |
3879 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3880 | */ | |
e1fc3b14 | 3881 | if (!net->sctp.addip_noauth && !asconf_ack->auth) |
68d75469 XL |
3882 | return sctp_sf_discard_chunk(net, ep, asoc, type, arg, |
3883 | commands); | |
6afd2e83 | 3884 | |
1da177e4 | 3885 | /* Make sure that the ADDIP chunk has a valid length. */ |
68d75469 XL |
3886 | if (!sctp_chunk_length_valid(asconf_ack, |
3887 | sizeof(struct sctp_addip_chunk))) | |
24cb81a6 | 3888 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
3889 | commands); |
3890 | ||
65205cc4 | 3891 | addip_hdr = (struct sctp_addiphdr *)asconf_ack->skb->data; |
1da177e4 LT |
3892 | rcvd_serial = ntohl(addip_hdr->serial); |
3893 | ||
6f4c618d | 3894 | /* Verify the ASCONF-ACK chunk before processing it. */ |
9de7922b | 3895 | if (!sctp_verify_asconf(asoc, asconf_ack, false, &err_param)) |
24cb81a6 | 3896 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, |
ba016670 | 3897 | (void *)err_param, commands); |
6f4c618d | 3898 | |
1da177e4 | 3899 | if (last_asconf) { |
65205cc4 | 3900 | addip_hdr = (struct sctp_addiphdr *)last_asconf->subh.addip_hdr; |
1da177e4 LT |
3901 | sent_serial = ntohl(addip_hdr->serial); |
3902 | } else { | |
3903 | sent_serial = asoc->addip_serial - 1; | |
3904 | } | |
3905 | ||
3906 | /* D0) If an endpoint receives an ASCONF-ACK that is greater than or | |
3907 | * equal to the next serial number to be used but no ASCONF chunk is | |
3908 | * outstanding the endpoint MUST ABORT the association. Note that a | |
3909 | * sequence number is greater than if it is no more than 2^^31-1 | |
3910 | * larger than the current sequence number (using serial arithmetic). | |
3911 | */ | |
3912 | if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) && | |
3913 | !(asoc->addip_last_asconf)) { | |
3914 | abort = sctp_make_abort(asoc, asconf_ack, | |
d8238d9d | 3915 | sizeof(struct sctp_errhdr)); |
1da177e4 | 3916 | if (abort) { |
00f1c2df | 3917 | sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0); |
1da177e4 LT |
3918 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3919 | SCTP_CHUNK(abort)); | |
3920 | } | |
3921 | /* We are going to ABORT, so we might as well stop | |
3922 | * processing the rest of the chunks in the packet. | |
3923 | */ | |
3924 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3925 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
cb3f837b | 3926 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 | 3927 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3928 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3929 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3930 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
b01a2407 EB |
3931 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
3932 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3933 | return SCTP_DISPOSITION_ABORT; |
3934 | } | |
3935 | ||
3936 | if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) { | |
3937 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3938 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3939 | ||
3940 | if (!sctp_process_asconf_ack((struct sctp_association *)asoc, | |
fbd01973 XL |
3941 | asconf_ack)) |
3942 | return sctp_send_next_asconf(net, ep, | |
3943 | (struct sctp_association *)asoc, | |
3944 | type, commands); | |
1da177e4 LT |
3945 | |
3946 | abort = sctp_make_abort(asoc, asconf_ack, | |
d8238d9d | 3947 | sizeof(struct sctp_errhdr)); |
1da177e4 | 3948 | if (abort) { |
00f1c2df | 3949 | sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0); |
1da177e4 LT |
3950 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3951 | SCTP_CHUNK(abort)); | |
3952 | } | |
3953 | /* We are going to ABORT, so we might as well stop | |
3954 | * processing the rest of the chunks in the packet. | |
3955 | */ | |
cb3f837b | 3956 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 | 3957 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3958 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3959 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3960 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
b01a2407 EB |
3961 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
3962 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
3963 | return SCTP_DISPOSITION_ABORT; |
3964 | } | |
3965 | ||
3966 | return SCTP_DISPOSITION_DISCARD; | |
3967 | } | |
3968 | ||
2040d3d7 | 3969 | /* RE-CONFIG Section 5.2 Upon reception of an RECONF Chunk. */ |
172a1599 XL |
3970 | enum sctp_disposition sctp_sf_do_reconf(struct net *net, |
3971 | const struct sctp_endpoint *ep, | |
3972 | const struct sctp_association *asoc, | |
3973 | const union sctp_subtype type, | |
3974 | void *arg, | |
3975 | struct sctp_cmd_seq *commands) | |
2040d3d7 XL |
3976 | { |
3977 | struct sctp_paramhdr *err_param = NULL; | |
3978 | struct sctp_chunk *chunk = arg; | |
3979 | struct sctp_reconf_chunk *hdr; | |
3980 | union sctp_params param; | |
3981 | ||
3982 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3983 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3984 | SCTP_NULL()); | |
3985 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); | |
3986 | } | |
3987 | ||
3988 | /* Make sure that the RECONF chunk has a valid length. */ | |
3989 | if (!sctp_chunk_length_valid(chunk, sizeof(*hdr))) | |
3990 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, | |
3991 | commands); | |
3992 | ||
3993 | if (!sctp_verify_reconf(asoc, chunk, &err_param)) | |
3994 | return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, | |
3995 | (void *)err_param, commands); | |
3996 | ||
3997 | hdr = (struct sctp_reconf_chunk *)chunk->chunk_hdr; | |
3998 | sctp_walk_params(param, hdr, params) { | |
3999 | struct sctp_chunk *reply = NULL; | |
4000 | struct sctp_ulpevent *ev = NULL; | |
4001 | ||
4002 | if (param.p->type == SCTP_PARAM_RESET_OUT_REQUEST) | |
4003 | reply = sctp_process_strreset_outreq( | |
4004 | (struct sctp_association *)asoc, param, &ev); | |
4005 | else if (param.p->type == SCTP_PARAM_RESET_IN_REQUEST) | |
4006 | reply = sctp_process_strreset_inreq( | |
4007 | (struct sctp_association *)asoc, param, &ev); | |
692787ce XL |
4008 | else if (param.p->type == SCTP_PARAM_RESET_TSN_REQUEST) |
4009 | reply = sctp_process_strreset_tsnreq( | |
4010 | (struct sctp_association *)asoc, param, &ev); | |
50a41591 XL |
4011 | else if (param.p->type == SCTP_PARAM_RESET_ADD_OUT_STREAMS) |
4012 | reply = sctp_process_strreset_addstrm_out( | |
4013 | (struct sctp_association *)asoc, param, &ev); | |
c5c4ebb3 XL |
4014 | else if (param.p->type == SCTP_PARAM_RESET_ADD_IN_STREAMS) |
4015 | reply = sctp_process_strreset_addstrm_in( | |
4016 | (struct sctp_association *)asoc, param, &ev); | |
11ae76e6 XL |
4017 | else if (param.p->type == SCTP_PARAM_RESET_RESPONSE) |
4018 | reply = sctp_process_strreset_resp( | |
4019 | (struct sctp_association *)asoc, param, &ev); | |
2040d3d7 XL |
4020 | |
4021 | if (ev) | |
4022 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
4023 | SCTP_ULPEVENT(ev)); | |
4024 | ||
4025 | if (reply) | |
4026 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4027 | SCTP_CHUNK(reply)); | |
4028 | } | |
4029 | ||
4030 | return SCTP_DISPOSITION_CONSUME; | |
4031 | } | |
4032 | ||
1da177e4 LT |
4033 | /* |
4034 | * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP | |
4035 | * | |
4036 | * When a FORWARD TSN chunk arrives, the data receiver MUST first update | |
4037 | * its cumulative TSN point to the value carried in the FORWARD TSN | |
4038 | * chunk, and then MUST further advance its cumulative TSN point locally | |
4039 | * if possible. | |
4040 | * After the above processing, the data receiver MUST stop reporting any | |
4041 | * missing TSNs earlier than or equal to the new cumulative TSN point. | |
4042 | * | |
4043 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
4044 | * | |
4045 | * The return value is the disposition of the chunk. | |
4046 | */ | |
172a1599 XL |
4047 | enum sctp_disposition sctp_sf_eat_fwd_tsn(struct net *net, |
4048 | const struct sctp_endpoint *ep, | |
4049 | const struct sctp_association *asoc, | |
4050 | const union sctp_subtype type, | |
4051 | void *arg, | |
4052 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4053 | { |
1da177e4 | 4054 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; |
172a1599 | 4055 | struct sctp_chunk *chunk = arg; |
1da177e4 LT |
4056 | __u16 len; |
4057 | __u32 tsn; | |
4058 | ||
4059 | if (!sctp_vtag_verify(chunk, asoc)) { | |
4060 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
4061 | SCTP_NULL()); | |
24cb81a6 | 4062 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
4063 | } |
4064 | ||
d15c9ede XL |
4065 | if (!asoc->peer.prsctp_capable) |
4066 | return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands); | |
4067 | ||
1da177e4 | 4068 | /* Make sure that the FORWARD_TSN chunk has valid length. */ |
0fc2ea92 | 4069 | if (!sctp_chunk_length_valid(chunk, sctp_ftsnchk_len(&asoc->stream))) |
24cb81a6 | 4070 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
4071 | commands); |
4072 | ||
4073 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
4074 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
4075 | len = ntohs(chunk->chunk_hdr->length); | |
4076 | len -= sizeof(struct sctp_chunkhdr); | |
4077 | skb_pull(chunk->skb, len); | |
4078 | ||
4079 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
bb33381d | 4080 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
4081 | |
4082 | /* The TSN is too high--silently discard the chunk and count on it | |
4083 | * getting retransmitted later. | |
4084 | */ | |
4085 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
4086 | goto discard_noforce; | |
4087 | ||
0fc2ea92 XL |
4088 | if (!asoc->stream.si->validate_ftsn(chunk)) |
4089 | goto discard_noforce; | |
9fcb95a1 | 4090 | |
1da177e4 | 4091 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
0fc2ea92 | 4092 | if (len > sctp_ftsnhdr_len(&asoc->stream)) |
d808ad9a | 4093 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 4094 | SCTP_CHUNK(chunk)); |
d808ad9a | 4095 | |
1da177e4 | 4096 | /* Count this as receiving DATA. */ |
9f70f46b | 4097 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) { |
1da177e4 LT |
4098 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
4099 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
4100 | } | |
d808ad9a | 4101 | |
1da177e4 | 4102 | /* FIXME: For now send a SACK, but DATA processing may |
d808ad9a | 4103 | * send another. |
1da177e4 LT |
4104 | */ |
4105 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); | |
1da177e4 LT |
4106 | |
4107 | return SCTP_DISPOSITION_CONSUME; | |
4108 | ||
4109 | discard_noforce: | |
4110 | return SCTP_DISPOSITION_DISCARD; | |
4111 | } | |
4112 | ||
172a1599 XL |
4113 | enum sctp_disposition sctp_sf_eat_fwd_tsn_fast( |
4114 | struct net *net, | |
4115 | const struct sctp_endpoint *ep, | |
4116 | const struct sctp_association *asoc, | |
4117 | const union sctp_subtype type, | |
4118 | void *arg, | |
4119 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4120 | { |
1da177e4 | 4121 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; |
172a1599 | 4122 | struct sctp_chunk *chunk = arg; |
1da177e4 LT |
4123 | __u16 len; |
4124 | __u32 tsn; | |
4125 | ||
4126 | if (!sctp_vtag_verify(chunk, asoc)) { | |
4127 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
4128 | SCTP_NULL()); | |
24cb81a6 | 4129 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
4130 | } |
4131 | ||
d15c9ede XL |
4132 | if (!asoc->peer.prsctp_capable) |
4133 | return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands); | |
4134 | ||
1da177e4 | 4135 | /* Make sure that the FORWARD_TSN chunk has a valid length. */ |
0fc2ea92 | 4136 | if (!sctp_chunk_length_valid(chunk, sctp_ftsnchk_len(&asoc->stream))) |
24cb81a6 | 4137 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
4138 | commands); |
4139 | ||
4140 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
4141 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
4142 | len = ntohs(chunk->chunk_hdr->length); | |
4143 | len -= sizeof(struct sctp_chunkhdr); | |
4144 | skb_pull(chunk->skb, len); | |
4145 | ||
4146 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
bb33381d | 4147 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
4148 | |
4149 | /* The TSN is too high--silently discard the chunk and count on it | |
4150 | * getting retransmitted later. | |
4151 | */ | |
4152 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
4153 | goto gen_shutdown; | |
4154 | ||
0fc2ea92 XL |
4155 | if (!asoc->stream.si->validate_ftsn(chunk)) |
4156 | goto gen_shutdown; | |
9fcb95a1 | 4157 | |
1da177e4 | 4158 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
0fc2ea92 | 4159 | if (len > sctp_ftsnhdr_len(&asoc->stream)) |
d808ad9a | 4160 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 4161 | SCTP_CHUNK(chunk)); |
d808ad9a | 4162 | |
1da177e4 LT |
4163 | /* Go a head and force a SACK, since we are shutting down. */ |
4164 | gen_shutdown: | |
4165 | /* Implementor's Guide. | |
4166 | * | |
4167 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
4168 | * respond to each received packet containing one or more DATA chunk(s) | |
4169 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
4170 | */ | |
4171 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
4172 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
4173 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
4174 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4175 | ||
d808ad9a | 4176 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
4177 | } |
4178 | ||
bbd0d598 | 4179 | /* |
25985edc | 4180 | * SCTP-AUTH Section 6.3 Receiving authenticated chukns |
bbd0d598 VY |
4181 | * |
4182 | * The receiver MUST use the HMAC algorithm indicated in the HMAC | |
4183 | * Identifier field. If this algorithm was not specified by the | |
4184 | * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk | |
4185 | * during association setup, the AUTH chunk and all chunks after it MUST | |
4186 | * be discarded and an ERROR chunk SHOULD be sent with the error cause | |
4187 | * defined in Section 4.1. | |
4188 | * | |
4189 | * If an endpoint with no shared key receives a Shared Key Identifier | |
4190 | * other than 0, it MUST silently discard all authenticated chunks. If | |
4191 | * the endpoint has at least one endpoint pair shared key for the peer, | |
4192 | * it MUST use the key specified by the Shared Key Identifier if a | |
4193 | * key has been configured for that Shared Key Identifier. If no | |
4194 | * endpoint pair shared key has been configured for that Shared Key | |
4195 | * Identifier, all authenticated chunks MUST be silently discarded. | |
4196 | * | |
4197 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
4198 | * | |
4199 | * The return value is the disposition of the chunk. | |
4200 | */ | |
4785c7ae | 4201 | static enum sctp_ierror sctp_sf_authenticate( |
172a1599 | 4202 | const struct sctp_association *asoc, |
172a1599 | 4203 | struct sctp_chunk *chunk) |
bbd0d598 | 4204 | { |
1b1e0bc9 | 4205 | struct sctp_shared_key *sh_key = NULL; |
bbd0d598 | 4206 | struct sctp_authhdr *auth_hdr; |
172a1599 | 4207 | __u8 *save_digest, *digest; |
bbd0d598 VY |
4208 | struct sctp_hmac *hmac; |
4209 | unsigned int sig_len; | |
4210 | __u16 key_id; | |
bbd0d598 VY |
4211 | |
4212 | /* Pull in the auth header, so we can do some more verification */ | |
4213 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
4214 | chunk->subh.auth_hdr = auth_hdr; | |
bb96dec7 | 4215 | skb_pull(chunk->skb, sizeof(*auth_hdr)); |
bbd0d598 | 4216 | |
02582e9b | 4217 | /* Make sure that we support the HMAC algorithm from the auth |
bbd0d598 VY |
4218 | * chunk. |
4219 | */ | |
4220 | if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id)) | |
4221 | return SCTP_IERROR_AUTH_BAD_HMAC; | |
4222 | ||
4223 | /* Make sure that the provided shared key identifier has been | |
4224 | * configured | |
4225 | */ | |
4226 | key_id = ntohs(auth_hdr->shkey_id); | |
1b1e0bc9 XL |
4227 | if (key_id != asoc->active_key_id) { |
4228 | sh_key = sctp_auth_get_shkey(asoc, key_id); | |
4229 | if (!sh_key) | |
4230 | return SCTP_IERROR_AUTH_BAD_KEYID; | |
4231 | } | |
bbd0d598 VY |
4232 | |
4233 | /* Make sure that the length of the signature matches what | |
4234 | * we expect. | |
4235 | */ | |
bb96dec7 XL |
4236 | sig_len = ntohs(chunk->chunk_hdr->length) - |
4237 | sizeof(struct sctp_auth_chunk); | |
bbd0d598 VY |
4238 | hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id)); |
4239 | if (sig_len != hmac->hmac_len) | |
4240 | return SCTP_IERROR_PROTO_VIOLATION; | |
4241 | ||
4242 | /* Now that we've done validation checks, we can compute and | |
4243 | * verify the hmac. The steps involved are: | |
4244 | * 1. Save the digest from the chunk. | |
4245 | * 2. Zero out the digest in the chunk. | |
4246 | * 3. Compute the new digest | |
4247 | * 4. Compare saved and new digests. | |
4248 | */ | |
4249 | digest = auth_hdr->hmac; | |
4250 | skb_pull(chunk->skb, sig_len); | |
4251 | ||
4252 | save_digest = kmemdup(digest, sig_len, GFP_ATOMIC); | |
4253 | if (!save_digest) | |
4254 | goto nomem; | |
4255 | ||
4256 | memset(digest, 0, sig_len); | |
4257 | ||
4258 | sctp_auth_calculate_hmac(asoc, chunk->skb, | |
bb96dec7 | 4259 | (struct sctp_auth_chunk *)chunk->chunk_hdr, |
1b1e0bc9 | 4260 | sh_key, GFP_ATOMIC); |
bbd0d598 VY |
4261 | |
4262 | /* Discard the packet if the digests do not match */ | |
4263 | if (memcmp(save_digest, digest, sig_len)) { | |
4264 | kfree(save_digest); | |
4265 | return SCTP_IERROR_BAD_SIG; | |
4266 | } | |
4267 | ||
4268 | kfree(save_digest); | |
4269 | chunk->auth = 1; | |
4270 | ||
4271 | return SCTP_IERROR_NO_ERROR; | |
4272 | nomem: | |
4273 | return SCTP_IERROR_NOMEM; | |
4274 | } | |
4275 | ||
172a1599 XL |
4276 | enum sctp_disposition sctp_sf_eat_auth(struct net *net, |
4277 | const struct sctp_endpoint *ep, | |
4278 | const struct sctp_association *asoc, | |
4279 | const union sctp_subtype type, | |
4280 | void *arg, struct sctp_cmd_seq *commands) | |
bbd0d598 | 4281 | { |
bbd0d598 | 4282 | struct sctp_chunk *chunk = arg; |
4785c7ae | 4283 | struct sctp_authhdr *auth_hdr; |
bbd0d598 | 4284 | struct sctp_chunk *err_chunk; |
4785c7ae | 4285 | enum sctp_ierror error; |
bbd0d598 | 4286 | |
d2f19fa1 WY |
4287 | /* Make sure that the peer has AUTH capable */ |
4288 | if (!asoc->peer.auth_capable) | |
24cb81a6 | 4289 | return sctp_sf_unk_chunk(net, ep, asoc, type, arg, commands); |
d2f19fa1 | 4290 | |
bbd0d598 VY |
4291 | if (!sctp_vtag_verify(chunk, asoc)) { |
4292 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
4293 | SCTP_NULL()); | |
24cb81a6 | 4294 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
bbd0d598 VY |
4295 | } |
4296 | ||
4297 | /* Make sure that the AUTH chunk has valid length. */ | |
4298 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk))) | |
24cb81a6 | 4299 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
bbd0d598 VY |
4300 | commands); |
4301 | ||
4302 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
59d8d443 | 4303 | error = sctp_sf_authenticate(asoc, chunk); |
bbd0d598 | 4304 | switch (error) { |
7fd71b1e JP |
4305 | case SCTP_IERROR_AUTH_BAD_HMAC: |
4306 | /* Generate the ERROR chunk and discard the rest | |
4307 | * of the packet | |
4308 | */ | |
4309 | err_chunk = sctp_make_op_error(asoc, chunk, | |
4310 | SCTP_ERROR_UNSUP_HMAC, | |
4311 | &auth_hdr->hmac_id, | |
4312 | sizeof(__u16), 0); | |
4313 | if (err_chunk) { | |
4314 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4315 | SCTP_CHUNK(err_chunk)); | |
4316 | } | |
4317 | /* Fall Through */ | |
4318 | case SCTP_IERROR_AUTH_BAD_KEYID: | |
4319 | case SCTP_IERROR_BAD_SIG: | |
24cb81a6 | 4320 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
7fd71b1e JP |
4321 | |
4322 | case SCTP_IERROR_PROTO_VIOLATION: | |
24cb81a6 | 4323 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
7fd71b1e JP |
4324 | commands); |
4325 | ||
4326 | case SCTP_IERROR_NOMEM: | |
4327 | return SCTP_DISPOSITION_NOMEM; | |
4328 | ||
4329 | default: /* Prevent gcc warnings */ | |
4330 | break; | |
bbd0d598 VY |
4331 | } |
4332 | ||
65b07e5d VY |
4333 | if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) { |
4334 | struct sctp_ulpevent *ev; | |
4335 | ||
4336 | ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id), | |
ec2e506c | 4337 | SCTP_AUTH_NEW_KEY, GFP_ATOMIC); |
65b07e5d VY |
4338 | |
4339 | if (!ev) | |
4340 | return -ENOMEM; | |
4341 | ||
4342 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
4343 | SCTP_ULPEVENT(ev)); | |
4344 | } | |
4345 | ||
bbd0d598 VY |
4346 | return SCTP_DISPOSITION_CONSUME; |
4347 | } | |
4348 | ||
1da177e4 LT |
4349 | /* |
4350 | * Process an unknown chunk. | |
4351 | * | |
4352 | * Section: 3.2. Also, 2.1 in the implementor's guide. | |
4353 | * | |
4354 | * Chunk Types are encoded such that the highest-order two bits specify | |
4355 | * the action that must be taken if the processing endpoint does not | |
4356 | * recognize the Chunk Type. | |
4357 | * | |
4358 | * 00 - Stop processing this SCTP packet and discard it, do not process | |
4359 | * any further chunks within it. | |
4360 | * | |
4361 | * 01 - Stop processing this SCTP packet and discard it, do not process | |
4362 | * any further chunks within it, and report the unrecognized | |
4363 | * chunk in an 'Unrecognized Chunk Type'. | |
4364 | * | |
4365 | * 10 - Skip this chunk and continue processing. | |
4366 | * | |
4367 | * 11 - Skip this chunk and continue processing, but report in an ERROR | |
4368 | * Chunk using the 'Unrecognized Chunk Type' cause of error. | |
4369 | * | |
4370 | * The return value is the disposition of the chunk. | |
4371 | */ | |
172a1599 XL |
4372 | enum sctp_disposition sctp_sf_unk_chunk(struct net *net, |
4373 | const struct sctp_endpoint *ep, | |
4374 | const struct sctp_association *asoc, | |
4375 | const union sctp_subtype type, | |
4376 | void *arg, | |
4377 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
4378 | { |
4379 | struct sctp_chunk *unk_chunk = arg; | |
4380 | struct sctp_chunk *err_chunk; | |
922dbc5b | 4381 | struct sctp_chunkhdr *hdr; |
1da177e4 | 4382 | |
bb33381d | 4383 | pr_debug("%s: processing unknown chunk id:%d\n", __func__, type.chunk); |
1da177e4 LT |
4384 | |
4385 | if (!sctp_vtag_verify(unk_chunk, asoc)) | |
24cb81a6 | 4386 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
4387 | |
4388 | /* Make sure that the chunk has a valid length. | |
4389 | * Since we don't know the chunk type, we use a general | |
4390 | * chunkhdr structure to make a comparison. | |
4391 | */ | |
922dbc5b | 4392 | if (!sctp_chunk_length_valid(unk_chunk, sizeof(*hdr))) |
24cb81a6 | 4393 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
1da177e4 LT |
4394 | commands); |
4395 | ||
4396 | switch (type.chunk & SCTP_CID_ACTION_MASK) { | |
4397 | case SCTP_CID_ACTION_DISCARD: | |
4398 | /* Discard the packet. */ | |
24cb81a6 | 4399 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 4400 | case SCTP_CID_ACTION_DISCARD_ERR: |
1da177e4 LT |
4401 | /* Generate an ERROR chunk as response. */ |
4402 | hdr = unk_chunk->chunk_hdr; | |
4403 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4404 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
e2f036a9 | 4405 | SCTP_PAD4(ntohs(hdr->length)), |
6383cfb3 | 4406 | 0); |
1da177e4 LT |
4407 | if (err_chunk) { |
4408 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4409 | SCTP_CHUNK(err_chunk)); | |
4410 | } | |
2e3216cd VY |
4411 | |
4412 | /* Discard the packet. */ | |
24cb81a6 | 4413 | sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); |
1da177e4 | 4414 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
4415 | case SCTP_CID_ACTION_SKIP: |
4416 | /* Skip the chunk. */ | |
4417 | return SCTP_DISPOSITION_DISCARD; | |
1da177e4 LT |
4418 | case SCTP_CID_ACTION_SKIP_ERR: |
4419 | /* Generate an ERROR chunk as response. */ | |
4420 | hdr = unk_chunk->chunk_hdr; | |
4421 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4422 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
e2f036a9 | 4423 | SCTP_PAD4(ntohs(hdr->length)), |
6383cfb3 | 4424 | 0); |
1da177e4 LT |
4425 | if (err_chunk) { |
4426 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4427 | SCTP_CHUNK(err_chunk)); | |
4428 | } | |
4429 | /* Skip the chunk. */ | |
4430 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
4431 | default: |
4432 | break; | |
4433 | } | |
4434 | ||
4435 | return SCTP_DISPOSITION_DISCARD; | |
4436 | } | |
4437 | ||
4438 | /* | |
4439 | * Discard the chunk. | |
4440 | * | |
4441 | * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2 | |
4442 | * [Too numerous to mention...] | |
4443 | * Verification Tag: No verification needed. | |
4444 | * Inputs | |
4445 | * (endpoint, asoc, chunk) | |
4446 | * | |
4447 | * Outputs | |
4448 | * (asoc, reply_msg, msg_up, timers, counters) | |
4449 | * | |
4450 | * The return value is the disposition of the chunk. | |
4451 | */ | |
172a1599 XL |
4452 | enum sctp_disposition sctp_sf_discard_chunk(struct net *net, |
4453 | const struct sctp_endpoint *ep, | |
4454 | const struct sctp_association *asoc, | |
4455 | const union sctp_subtype type, | |
4456 | void *arg, | |
4457 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4458 | { |
ece25dfa VY |
4459 | struct sctp_chunk *chunk = arg; |
4460 | ||
4461 | /* Make sure that the chunk has a valid length. | |
4462 | * Since we don't know the chunk type, we use a general | |
4463 | * chunkhdr structure to make a comparison. | |
4464 | */ | |
922dbc5b | 4465 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 4466 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
4467 | commands); |
4468 | ||
bb33381d DB |
4469 | pr_debug("%s: chunk:%d is discarded\n", __func__, type.chunk); |
4470 | ||
1da177e4 LT |
4471 | return SCTP_DISPOSITION_DISCARD; |
4472 | } | |
4473 | ||
4474 | /* | |
4475 | * Discard the whole packet. | |
4476 | * | |
4477 | * Section: 8.4 2) | |
4478 | * | |
4479 | * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST | |
4480 | * silently discard the OOTB packet and take no further action. | |
1da177e4 LT |
4481 | * |
4482 | * Verification Tag: No verification necessary | |
4483 | * | |
4484 | * Inputs | |
4485 | * (endpoint, asoc, chunk) | |
4486 | * | |
4487 | * Outputs | |
4488 | * (asoc, reply_msg, msg_up, timers, counters) | |
4489 | * | |
4490 | * The return value is the disposition of the chunk. | |
4491 | */ | |
172a1599 XL |
4492 | enum sctp_disposition sctp_sf_pdiscard(struct net *net, |
4493 | const struct sctp_endpoint *ep, | |
4494 | const struct sctp_association *asoc, | |
4495 | const union sctp_subtype type, | |
4496 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 | 4497 | { |
24cb81a6 | 4498 | SCTP_INC_STATS(net, SCTP_MIB_IN_PKT_DISCARDS); |
1da177e4 LT |
4499 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
4500 | ||
4501 | return SCTP_DISPOSITION_CONSUME; | |
4502 | } | |
4503 | ||
4504 | ||
4505 | /* | |
4506 | * The other end is violating protocol. | |
4507 | * | |
4508 | * Section: Not specified | |
4509 | * Verification Tag: Not specified | |
4510 | * Inputs | |
4511 | * (endpoint, asoc, chunk) | |
4512 | * | |
4513 | * Outputs | |
4514 | * (asoc, reply_msg, msg_up, timers, counters) | |
4515 | * | |
4516 | * We simply tag the chunk as a violation. The state machine will log | |
4517 | * the violation and continue. | |
4518 | */ | |
172a1599 XL |
4519 | enum sctp_disposition sctp_sf_violation(struct net *net, |
4520 | const struct sctp_endpoint *ep, | |
4521 | const struct sctp_association *asoc, | |
4522 | const union sctp_subtype type, | |
4523 | void *arg, | |
4524 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4525 | { |
ece25dfa VY |
4526 | struct sctp_chunk *chunk = arg; |
4527 | ||
4528 | /* Make sure that the chunk has a valid length. */ | |
922dbc5b | 4529 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_chunkhdr))) |
24cb81a6 | 4530 | return sctp_sf_violation_chunklen(net, ep, asoc, type, arg, |
ece25dfa VY |
4531 | commands); |
4532 | ||
1da177e4 LT |
4533 | return SCTP_DISPOSITION_VIOLATION; |
4534 | } | |
4535 | ||
1da177e4 | 4536 | /* |
aecedeab | 4537 | * Common function to handle a protocol violation. |
1da177e4 | 4538 | */ |
172a1599 XL |
4539 | static enum sctp_disposition sctp_sf_abort_violation( |
4540 | struct net *net, | |
4541 | const struct sctp_endpoint *ep, | |
4542 | const struct sctp_association *asoc, | |
4543 | void *arg, | |
4544 | struct sctp_cmd_seq *commands, | |
4545 | const __u8 *payload, | |
4546 | const size_t paylen) | |
1da177e4 | 4547 | { |
ece25dfa | 4548 | struct sctp_packet *packet = NULL; |
1da177e4 LT |
4549 | struct sctp_chunk *chunk = arg; |
4550 | struct sctp_chunk *abort = NULL; | |
1da177e4 | 4551 | |
bbd0d598 VY |
4552 | /* SCTP-AUTH, Section 6.3: |
4553 | * It should be noted that if the receiver wants to tear | |
4554 | * down an association in an authenticated way only, the | |
4555 | * handling of malformed packets should not result in | |
4556 | * tearing down the association. | |
4557 | * | |
4558 | * This means that if we only want to abort associations | |
4559 | * in an authenticated way (i.e AUTH+ABORT), then we | |
25985edc | 4560 | * can't destroy this association just because the packet |
bbd0d598 VY |
4561 | * was malformed. |
4562 | */ | |
4563 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
4564 | goto discard; | |
4565 | ||
9abed245 JJ |
4566 | /* Make the abort chunk. */ |
4567 | abort = sctp_make_abort_violation(asoc, chunk, payload, paylen); | |
4568 | if (!abort) | |
4569 | goto nomem; | |
4570 | ||
ece25dfa | 4571 | if (asoc) { |
f4ad85ca GJ |
4572 | /* Treat INIT-ACK as a special case during COOKIE-WAIT. */ |
4573 | if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK && | |
4574 | !asoc->peer.i.init_tag) { | |
cb1844c4 | 4575 | struct sctp_initack_chunk *initack; |
f4ad85ca | 4576 | |
cb1844c4 XL |
4577 | initack = (struct sctp_initack_chunk *)chunk->chunk_hdr; |
4578 | if (!sctp_chunk_length_valid(chunk, sizeof(*initack))) | |
f4ad85ca GJ |
4579 | abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T; |
4580 | else { | |
4581 | unsigned int inittag; | |
4582 | ||
4583 | inittag = ntohl(initack->init_hdr.init_tag); | |
4584 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG, | |
4585 | SCTP_U32(inittag)); | |
4586 | } | |
4587 | } | |
4588 | ||
ece25dfa | 4589 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
b01a2407 | 4590 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 | 4591 | |
ece25dfa VY |
4592 | if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { |
4593 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4594 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4595 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4596 | SCTP_ERROR(ECONNREFUSED)); | |
4597 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
4598 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4599 | } else { | |
4600 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4601 | SCTP_ERROR(ECONNABORTED)); | |
4602 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4603 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
b01a2407 | 4604 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); |
ece25dfa | 4605 | } |
1da177e4 | 4606 | } else { |
2ce95503 | 4607 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
ece25dfa VY |
4608 | |
4609 | if (!packet) | |
4610 | goto nomem_pkt; | |
4611 | ||
4612 | if (sctp_test_T_bit(abort)) | |
4613 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
4614 | ||
4615 | abort->skb->sk = ep->base.sk; | |
4616 | ||
4617 | sctp_packet_append_chunk(packet, abort); | |
4618 | ||
4619 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
4620 | SCTP_PACKET(packet)); | |
4621 | ||
b01a2407 | 4622 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
4623 | } |
4624 | ||
b01a2407 | 4625 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
d808ad9a | 4626 | |
56eb82bb | 4627 | discard: |
24cb81a6 | 4628 | sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
1da177e4 LT |
4629 | return SCTP_DISPOSITION_ABORT; |
4630 | ||
ece25dfa VY |
4631 | nomem_pkt: |
4632 | sctp_chunk_free(abort); | |
1da177e4 LT |
4633 | nomem: |
4634 | return SCTP_DISPOSITION_NOMEM; | |
4635 | } | |
4636 | ||
aecedeab WY |
4637 | /* |
4638 | * Handle a protocol violation when the chunk length is invalid. | |
025dfdaf | 4639 | * "Invalid" length is identified as smaller than the minimal length a |
aecedeab | 4640 | * given chunk can be. For example, a SACK chunk has invalid length |
d4d6c614 | 4641 | * if its length is set to be smaller than the size of struct sctp_sack_chunk. |
aecedeab WY |
4642 | * |
4643 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4644 | * error code. | |
4645 | * | |
4646 | * Section: Not specified | |
4647 | * Verification Tag: Nothing to do | |
4648 | * Inputs | |
4649 | * (endpoint, asoc, chunk) | |
4650 | * | |
4651 | * Outputs | |
4652 | * (reply_msg, msg_up, counters) | |
4653 | * | |
4654 | * Generate an ABORT chunk and terminate the association. | |
4655 | */ | |
172a1599 XL |
4656 | static enum sctp_disposition sctp_sf_violation_chunklen( |
4657 | struct net *net, | |
4658 | const struct sctp_endpoint *ep, | |
4659 | const struct sctp_association *asoc, | |
4660 | const union sctp_subtype type, | |
4661 | void *arg, | |
4662 | struct sctp_cmd_seq *commands) | |
aecedeab | 4663 | { |
cb3f837b | 4664 | static const char err_str[] = "The following chunk had invalid length:"; |
aecedeab | 4665 | |
24cb81a6 | 4666 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
172a1599 | 4667 | sizeof(err_str)); |
aecedeab WY |
4668 | } |
4669 | ||
6f4c618d WY |
4670 | /* |
4671 | * Handle a protocol violation when the parameter length is invalid. | |
33c7cfdb SW |
4672 | * If the length is smaller than the minimum length of a given parameter, |
4673 | * or accumulated length in multi parameters exceeds the end of the chunk, | |
4674 | * the length is considered as invalid. | |
6f4c618d | 4675 | */ |
172a1599 XL |
4676 | static enum sctp_disposition sctp_sf_violation_paramlen( |
4677 | struct net *net, | |
4678 | const struct sctp_endpoint *ep, | |
4679 | const struct sctp_association *asoc, | |
4680 | const union sctp_subtype type, | |
4681 | void *arg, void *ext, | |
4682 | struct sctp_cmd_seq *commands) | |
ba016670 | 4683 | { |
ba016670 WY |
4684 | struct sctp_paramhdr *param = ext; |
4685 | struct sctp_chunk *abort = NULL; | |
172a1599 | 4686 | struct sctp_chunk *chunk = arg; |
6f4c618d | 4687 | |
ba016670 WY |
4688 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) |
4689 | goto discard; | |
4690 | ||
4691 | /* Make the abort chunk. */ | |
4692 | abort = sctp_make_violation_paramlen(asoc, chunk, param); | |
4693 | if (!abort) | |
4694 | goto nomem; | |
4695 | ||
4696 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
b01a2407 | 4697 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
ba016670 WY |
4698 | |
4699 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4700 | SCTP_ERROR(ECONNABORTED)); | |
4701 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4702 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
b01a2407 EB |
4703 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); |
4704 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); | |
ba016670 WY |
4705 | |
4706 | discard: | |
24cb81a6 | 4707 | sctp_sf_pdiscard(net, ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
ba016670 WY |
4708 | return SCTP_DISPOSITION_ABORT; |
4709 | nomem: | |
4710 | return SCTP_DISPOSITION_NOMEM; | |
6f4c618d WY |
4711 | } |
4712 | ||
aecedeab WY |
4713 | /* Handle a protocol violation when the peer trying to advance the |
4714 | * cumulative tsn ack to a point beyond the max tsn currently sent. | |
4715 | * | |
4716 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4717 | * error code. | |
4718 | */ | |
172a1599 XL |
4719 | static enum sctp_disposition sctp_sf_violation_ctsn( |
4720 | struct net *net, | |
4721 | const struct sctp_endpoint *ep, | |
4722 | const struct sctp_association *asoc, | |
4723 | const union sctp_subtype type, | |
4724 | void *arg, | |
4725 | struct sctp_cmd_seq *commands) | |
aecedeab | 4726 | { |
cb3f837b | 4727 | static const char err_str[] = "The cumulative tsn ack beyond the max tsn currently sent:"; |
aecedeab | 4728 | |
24cb81a6 | 4729 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
172a1599 | 4730 | sizeof(err_str)); |
aecedeab WY |
4731 | } |
4732 | ||
ece25dfa | 4733 | /* Handle protocol violation of an invalid chunk bundling. For example, |
25985edc | 4734 | * when we have an association and we receive bundled INIT-ACK, or |
ece25dfa | 4735 | * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle" |
25985edc | 4736 | * statement from the specs. Additionally, there might be an attacker |
ece25dfa VY |
4737 | * on the path and we may not want to continue this communication. |
4738 | */ | |
172a1599 XL |
4739 | static enum sctp_disposition sctp_sf_violation_chunk( |
4740 | struct net *net, | |
4741 | const struct sctp_endpoint *ep, | |
4742 | const struct sctp_association *asoc, | |
4743 | const union sctp_subtype type, | |
4744 | void *arg, | |
4745 | struct sctp_cmd_seq *commands) | |
ece25dfa | 4746 | { |
cb3f837b | 4747 | static const char err_str[] = "The following chunk violates protocol:"; |
ece25dfa VY |
4748 | |
4749 | if (!asoc) | |
24cb81a6 | 4750 | return sctp_sf_violation(net, ep, asoc, type, arg, commands); |
ece25dfa | 4751 | |
24cb81a6 | 4752 | return sctp_sf_abort_violation(net, ep, asoc, arg, commands, err_str, |
172a1599 | 4753 | sizeof(err_str)); |
ece25dfa | 4754 | } |
1da177e4 LT |
4755 | /*************************************************************************** |
4756 | * These are the state functions for handling primitive (Section 10) events. | |
4757 | ***************************************************************************/ | |
4758 | /* | |
4759 | * sctp_sf_do_prm_asoc | |
4760 | * | |
4761 | * Section: 10.1 ULP-to-SCTP | |
4762 | * B) Associate | |
4763 | * | |
4764 | * Format: ASSOCIATE(local SCTP instance name, destination transport addr, | |
4765 | * outbound stream count) | |
4766 | * -> association id [,destination transport addr list] [,outbound stream | |
4767 | * count] | |
4768 | * | |
4769 | * This primitive allows the upper layer to initiate an association to a | |
4770 | * specific peer endpoint. | |
4771 | * | |
4772 | * The peer endpoint shall be specified by one of the transport addresses | |
4773 | * which defines the endpoint (see Section 1.4). If the local SCTP | |
4774 | * instance has not been initialized, the ASSOCIATE is considered an | |
4775 | * error. | |
4776 | * [This is not relevant for the kernel implementation since we do all | |
4777 | * initialization at boot time. It we hadn't initialized we wouldn't | |
4778 | * get anywhere near this code.] | |
4779 | * | |
4780 | * An association id, which is a local handle to the SCTP association, | |
4781 | * will be returned on successful establishment of the association. If | |
4782 | * SCTP is not able to open an SCTP association with the peer endpoint, | |
4783 | * an error is returned. | |
4784 | * [In the kernel implementation, the struct sctp_association needs to | |
4785 | * be created BEFORE causing this primitive to run.] | |
4786 | * | |
4787 | * Other association parameters may be returned, including the | |
4788 | * complete destination transport addresses of the peer as well as the | |
4789 | * outbound stream count of the local endpoint. One of the transport | |
4790 | * address from the returned destination addresses will be selected by | |
4791 | * the local endpoint as default primary path for sending SCTP packets | |
4792 | * to this peer. The returned "destination transport addr list" can | |
4793 | * be used by the ULP to change the default primary path or to force | |
4794 | * sending a packet to a specific transport address. [All of this | |
4795 | * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING | |
4796 | * function.] | |
4797 | * | |
4798 | * Mandatory attributes: | |
4799 | * | |
4800 | * o local SCTP instance name - obtained from the INITIALIZE operation. | |
4801 | * [This is the argument asoc.] | |
4802 | * o destination transport addr - specified as one of the transport | |
4803 | * addresses of the peer endpoint with which the association is to be | |
4804 | * established. | |
4805 | * [This is asoc->peer.active_path.] | |
4806 | * o outbound stream count - the number of outbound streams the ULP | |
4807 | * would like to open towards this peer endpoint. | |
4808 | * [BUG: This is not currently implemented.] | |
4809 | * Optional attributes: | |
4810 | * | |
4811 | * None. | |
4812 | * | |
4813 | * The return value is a disposition. | |
4814 | */ | |
172a1599 XL |
4815 | enum sctp_disposition sctp_sf_do_prm_asoc(struct net *net, |
4816 | const struct sctp_endpoint *ep, | |
4817 | const struct sctp_association *asoc, | |
4818 | const union sctp_subtype type, | |
4819 | void *arg, | |
4820 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4821 | { |
26ac8e5f | 4822 | struct sctp_association *my_asoc; |
172a1599 | 4823 | struct sctp_chunk *repl; |
1da177e4 LT |
4824 | |
4825 | /* The comment below says that we enter COOKIE-WAIT AFTER | |
4826 | * sending the INIT, but that doesn't actually work in our | |
4827 | * implementation... | |
4828 | */ | |
4829 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4830 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
4831 | ||
4832 | /* RFC 2960 5.1 Normal Establishment of an Association | |
4833 | * | |
4834 | * A) "A" first sends an INIT chunk to "Z". In the INIT, "A" | |
4835 | * must provide its Verification Tag (Tag_A) in the Initiate | |
4836 | * Tag field. Tag_A SHOULD be a random number in the range of | |
4837 | * 1 to 4294967295 (see 5.3.1 for Tag value selection). ... | |
4838 | */ | |
4839 | ||
4840 | repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0); | |
4841 | if (!repl) | |
4842 | goto nomem; | |
4843 | ||
405426f6 DB |
4844 | /* Choose transport for INIT. */ |
4845 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4846 | SCTP_CHUNK(repl)); | |
4847 | ||
1da177e4 LT |
4848 | /* Cast away the const modifier, as we want to just |
4849 | * rerun it through as a sideffect. | |
4850 | */ | |
ab38fb04 VY |
4851 | my_asoc = (struct sctp_association *)asoc; |
4852 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc)); | |
1da177e4 LT |
4853 | |
4854 | /* After sending the INIT, "A" starts the T1-init timer and | |
4855 | * enters the COOKIE-WAIT state. | |
4856 | */ | |
4857 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4858 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4859 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4860 | return SCTP_DISPOSITION_CONSUME; | |
4861 | ||
4862 | nomem: | |
4863 | return SCTP_DISPOSITION_NOMEM; | |
4864 | } | |
4865 | ||
4866 | /* | |
4867 | * Process the SEND primitive. | |
4868 | * | |
4869 | * Section: 10.1 ULP-to-SCTP | |
4870 | * E) Send | |
4871 | * | |
4872 | * Format: SEND(association id, buffer address, byte count [,context] | |
4873 | * [,stream id] [,life time] [,destination transport address] | |
4874 | * [,unorder flag] [,no-bundle flag] [,payload protocol-id] ) | |
4875 | * -> result | |
4876 | * | |
4877 | * This is the main method to send user data via SCTP. | |
4878 | * | |
4879 | * Mandatory attributes: | |
4880 | * | |
4881 | * o association id - local handle to the SCTP association | |
4882 | * | |
4883 | * o buffer address - the location where the user message to be | |
4884 | * transmitted is stored; | |
4885 | * | |
4886 | * o byte count - The size of the user data in number of bytes; | |
4887 | * | |
4888 | * Optional attributes: | |
4889 | * | |
4890 | * o context - an optional 32 bit integer that will be carried in the | |
4891 | * sending failure notification to the ULP if the transportation of | |
4892 | * this User Message fails. | |
4893 | * | |
4894 | * o stream id - to indicate which stream to send the data on. If not | |
4895 | * specified, stream 0 will be used. | |
4896 | * | |
4897 | * o life time - specifies the life time of the user data. The user data | |
4898 | * will not be sent by SCTP after the life time expires. This | |
4899 | * parameter can be used to avoid efforts to transmit stale | |
4900 | * user messages. SCTP notifies the ULP if the data cannot be | |
4901 | * initiated to transport (i.e. sent to the destination via SCTP's | |
4902 | * send primitive) within the life time variable. However, the | |
4903 | * user data will be transmitted if SCTP has attempted to transmit a | |
4904 | * chunk before the life time expired. | |
4905 | * | |
4906 | * o destination transport address - specified as one of the destination | |
4907 | * transport addresses of the peer endpoint to which this packet | |
4908 | * should be sent. Whenever possible, SCTP should use this destination | |
4909 | * transport address for sending the packets, instead of the current | |
4910 | * primary path. | |
4911 | * | |
4912 | * o unorder flag - this flag, if present, indicates that the user | |
4913 | * would like the data delivered in an unordered fashion to the peer | |
4914 | * (i.e., the U flag is set to 1 on all DATA chunks carrying this | |
4915 | * message). | |
4916 | * | |
4917 | * o no-bundle flag - instructs SCTP not to bundle this user data with | |
4918 | * other outbound DATA chunks. SCTP MAY still bundle even when | |
4919 | * this flag is present, when faced with network congestion. | |
4920 | * | |
4921 | * o payload protocol-id - A 32 bit unsigned integer that is to be | |
4922 | * passed to the peer indicating the type of payload protocol data | |
4923 | * being transmitted. This value is passed as opaque data by SCTP. | |
4924 | * | |
4925 | * The return value is the disposition. | |
4926 | */ | |
172a1599 XL |
4927 | enum sctp_disposition sctp_sf_do_prm_send(struct net *net, |
4928 | const struct sctp_endpoint *ep, | |
4929 | const struct sctp_association *asoc, | |
4930 | const union sctp_subtype type, | |
4931 | void *arg, | |
4932 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4933 | { |
9c5c62be | 4934 | struct sctp_datamsg *msg = arg; |
1da177e4 | 4935 | |
9c5c62be | 4936 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_MSG, SCTP_DATAMSG(msg)); |
1da177e4 LT |
4937 | return SCTP_DISPOSITION_CONSUME; |
4938 | } | |
4939 | ||
4940 | /* | |
4941 | * Process the SHUTDOWN primitive. | |
4942 | * | |
4943 | * Section: 10.1: | |
4944 | * C) Shutdown | |
4945 | * | |
4946 | * Format: SHUTDOWN(association id) | |
4947 | * -> result | |
4948 | * | |
4949 | * Gracefully closes an association. Any locally queued user data | |
4950 | * will be delivered to the peer. The association will be terminated only | |
4951 | * after the peer acknowledges all the SCTP packets sent. A success code | |
4952 | * will be returned on successful termination of the association. If | |
4953 | * attempting to terminate the association results in a failure, an error | |
4954 | * code shall be returned. | |
4955 | * | |
4956 | * Mandatory attributes: | |
4957 | * | |
4958 | * o association id - local handle to the SCTP association | |
4959 | * | |
4960 | * Optional attributes: | |
4961 | * | |
4962 | * None. | |
4963 | * | |
4964 | * The return value is the disposition. | |
4965 | */ | |
172a1599 XL |
4966 | enum sctp_disposition sctp_sf_do_9_2_prm_shutdown( |
4967 | struct net *net, | |
4968 | const struct sctp_endpoint *ep, | |
4969 | const struct sctp_association *asoc, | |
4970 | const union sctp_subtype type, | |
4971 | void *arg, | |
4972 | struct sctp_cmd_seq *commands) | |
1da177e4 | 4973 | { |
172a1599 | 4974 | enum sctp_disposition disposition; |
1da177e4 LT |
4975 | |
4976 | /* From 9.2 Shutdown of an Association | |
4977 | * Upon receipt of the SHUTDOWN primitive from its upper | |
4978 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
4979 | * remains there until all outstanding data has been | |
4980 | * acknowledged by its peer. The endpoint accepts no new data | |
4981 | * from its upper layer, but retransmits data to the far end | |
4982 | * if necessary to fill gaps. | |
4983 | */ | |
4984 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4985 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
4986 | ||
1da177e4 LT |
4987 | disposition = SCTP_DISPOSITION_CONSUME; |
4988 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 4989 | disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type, |
1da177e4 LT |
4990 | arg, commands); |
4991 | } | |
172a1599 | 4992 | |
1da177e4 LT |
4993 | return disposition; |
4994 | } | |
4995 | ||
4996 | /* | |
4997 | * Process the ABORT primitive. | |
4998 | * | |
4999 | * Section: 10.1: | |
5000 | * C) Abort | |
5001 | * | |
5002 | * Format: Abort(association id [, cause code]) | |
5003 | * -> result | |
5004 | * | |
5005 | * Ungracefully closes an association. Any locally queued user data | |
5006 | * will be discarded and an ABORT chunk is sent to the peer. A success code | |
5007 | * will be returned on successful abortion of the association. If | |
5008 | * attempting to abort the association results in a failure, an error | |
5009 | * code shall be returned. | |
5010 | * | |
5011 | * Mandatory attributes: | |
5012 | * | |
5013 | * o association id - local handle to the SCTP association | |
5014 | * | |
5015 | * Optional attributes: | |
5016 | * | |
5017 | * o cause code - reason of the abort to be passed to the peer | |
5018 | * | |
5019 | * None. | |
5020 | * | |
5021 | * The return value is the disposition. | |
5022 | */ | |
172a1599 XL |
5023 | enum sctp_disposition sctp_sf_do_9_1_prm_abort( |
5024 | struct net *net, | |
5025 | const struct sctp_endpoint *ep, | |
5026 | const struct sctp_association *asoc, | |
5027 | const union sctp_subtype type, | |
5028 | void *arg, | |
5029 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5030 | { |
5031 | /* From 9.1 Abort of an Association | |
5032 | * Upon receipt of the ABORT primitive from its upper | |
5033 | * layer, the endpoint enters CLOSED state and | |
5034 | * discard all outstanding data has been | |
5035 | * acknowledged by its peer. The endpoint accepts no new data | |
5036 | * from its upper layer, but retransmits data to the far end | |
5037 | * if necessary to fill gaps. | |
5038 | */ | |
c164a9ba | 5039 | struct sctp_chunk *abort = arg; |
1da177e4 | 5040 | |
068d8bd3 XL |
5041 | if (abort) |
5042 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
1da177e4 LT |
5043 | |
5044 | /* Even if we can't send the ABORT due to low memory delete the | |
5045 | * TCB. This is a departure from our typical NOMEM handling. | |
5046 | */ | |
5047 | ||
8de8c873 SS |
5048 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5049 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 LT |
5050 | /* Delete the established association. */ |
5051 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5052 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 | 5053 | |
b01a2407 EB |
5054 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5055 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 | 5056 | |
649621e3 | 5057 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
5058 | } |
5059 | ||
5060 | /* We tried an illegal operation on an association which is closed. */ | |
172a1599 XL |
5061 | enum sctp_disposition sctp_sf_error_closed(struct net *net, |
5062 | const struct sctp_endpoint *ep, | |
5063 | const struct sctp_association *asoc, | |
5064 | const union sctp_subtype type, | |
5065 | void *arg, | |
5066 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5067 | { |
5068 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL)); | |
5069 | return SCTP_DISPOSITION_CONSUME; | |
5070 | } | |
5071 | ||
5072 | /* We tried an illegal operation on an association which is shutting | |
5073 | * down. | |
5074 | */ | |
172a1599 XL |
5075 | enum sctp_disposition sctp_sf_error_shutdown( |
5076 | struct net *net, | |
5077 | const struct sctp_endpoint *ep, | |
5078 | const struct sctp_association *asoc, | |
5079 | const union sctp_subtype type, | |
5080 | void *arg, | |
5081 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5082 | { |
5083 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, | |
5084 | SCTP_ERROR(-ESHUTDOWN)); | |
5085 | return SCTP_DISPOSITION_CONSUME; | |
5086 | } | |
5087 | ||
5088 | /* | |
5089 | * sctp_cookie_wait_prm_shutdown | |
5090 | * | |
5091 | * Section: 4 Note: 2 | |
5092 | * Verification Tag: | |
5093 | * Inputs | |
5094 | * (endpoint, asoc) | |
5095 | * | |
5096 | * The RFC does not explicitly address this issue, but is the route through the | |
5097 | * state table when someone issues a shutdown while in COOKIE_WAIT state. | |
5098 | * | |
5099 | * Outputs | |
5100 | * (timers) | |
5101 | */ | |
172a1599 XL |
5102 | enum sctp_disposition sctp_sf_cookie_wait_prm_shutdown( |
5103 | struct net *net, | |
5104 | const struct sctp_endpoint *ep, | |
5105 | const struct sctp_association *asoc, | |
5106 | const union sctp_subtype type, | |
5107 | void *arg, | |
5108 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5109 | { |
5110 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5111 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
5112 | ||
5113 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5114 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
5115 | ||
b01a2407 | 5116 | SCTP_INC_STATS(net, SCTP_MIB_SHUTDOWNS); |
1da177e4 LT |
5117 | |
5118 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
5119 | ||
5120 | return SCTP_DISPOSITION_DELETE_TCB; | |
5121 | } | |
5122 | ||
5123 | /* | |
5124 | * sctp_cookie_echoed_prm_shutdown | |
5125 | * | |
5126 | * Section: 4 Note: 2 | |
5127 | * Verification Tag: | |
5128 | * Inputs | |
5129 | * (endpoint, asoc) | |
5130 | * | |
5131 | * The RFC does not explcitly address this issue, but is the route through the | |
5132 | * state table when someone issues a shutdown while in COOKIE_ECHOED state. | |
5133 | * | |
5134 | * Outputs | |
5135 | * (timers) | |
5136 | */ | |
172a1599 XL |
5137 | enum sctp_disposition sctp_sf_cookie_echoed_prm_shutdown( |
5138 | struct net *net, | |
5139 | const struct sctp_endpoint *ep, | |
5140 | const struct sctp_association *asoc, | |
5141 | const union sctp_subtype type, | |
5142 | void *arg, | |
5143 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5144 | { |
5145 | /* There is a single T1 timer, so we should be able to use | |
5146 | * common function with the COOKIE-WAIT state. | |
5147 | */ | |
24cb81a6 | 5148 | return sctp_sf_cookie_wait_prm_shutdown(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5149 | } |
5150 | ||
5151 | /* | |
5152 | * sctp_sf_cookie_wait_prm_abort | |
5153 | * | |
5154 | * Section: 4 Note: 2 | |
5155 | * Verification Tag: | |
5156 | * Inputs | |
5157 | * (endpoint, asoc) | |
5158 | * | |
5159 | * The RFC does not explicitly address this issue, but is the route through the | |
5160 | * state table when someone issues an abort while in COOKIE_WAIT state. | |
5161 | * | |
5162 | * Outputs | |
5163 | * (timers) | |
5164 | */ | |
172a1599 XL |
5165 | enum sctp_disposition sctp_sf_cookie_wait_prm_abort( |
5166 | struct net *net, | |
5167 | const struct sctp_endpoint *ep, | |
5168 | const struct sctp_association *asoc, | |
5169 | const union sctp_subtype type, | |
5170 | void *arg, | |
5171 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5172 | { |
c164a9ba | 5173 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
5174 | |
5175 | /* Stop T1-init timer */ | |
5176 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5177 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
1da177e4 | 5178 | |
068d8bd3 XL |
5179 | if (abort) |
5180 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
1da177e4 LT |
5181 | |
5182 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5183 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
5184 | ||
b01a2407 | 5185 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
1da177e4 LT |
5186 | |
5187 | /* Even if we can't send the ABORT due to low memory delete the | |
5188 | * TCB. This is a departure from our typical NOMEM handling. | |
5189 | */ | |
5190 | ||
8de8c873 SS |
5191 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5192 | SCTP_ERROR(ECONNREFUSED)); | |
1da177e4 LT |
5193 | /* Delete the established association. */ |
5194 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 5195 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 | 5196 | |
649621e3 | 5197 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
5198 | } |
5199 | ||
5200 | /* | |
5201 | * sctp_sf_cookie_echoed_prm_abort | |
5202 | * | |
5203 | * Section: 4 Note: 3 | |
5204 | * Verification Tag: | |
5205 | * Inputs | |
5206 | * (endpoint, asoc) | |
5207 | * | |
5208 | * The RFC does not explcitly address this issue, but is the route through the | |
5209 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
5210 | * | |
5211 | * Outputs | |
5212 | * (timers) | |
5213 | */ | |
172a1599 XL |
5214 | enum sctp_disposition sctp_sf_cookie_echoed_prm_abort( |
5215 | struct net *net, | |
5216 | const struct sctp_endpoint *ep, | |
5217 | const struct sctp_association *asoc, | |
5218 | const union sctp_subtype type, | |
5219 | void *arg, | |
5220 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5221 | { |
5222 | /* There is a single T1 timer, so we should be able to use | |
5223 | * common function with the COOKIE-WAIT state. | |
5224 | */ | |
24cb81a6 | 5225 | return sctp_sf_cookie_wait_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5226 | } |
5227 | ||
5228 | /* | |
5229 | * sctp_sf_shutdown_pending_prm_abort | |
5230 | * | |
5231 | * Inputs | |
5232 | * (endpoint, asoc) | |
5233 | * | |
5234 | * The RFC does not explicitly address this issue, but is the route through the | |
5235 | * state table when someone issues an abort while in SHUTDOWN-PENDING state. | |
5236 | * | |
5237 | * Outputs | |
5238 | * (timers) | |
5239 | */ | |
172a1599 XL |
5240 | enum sctp_disposition sctp_sf_shutdown_pending_prm_abort( |
5241 | struct net *net, | |
5242 | const struct sctp_endpoint *ep, | |
5243 | const struct sctp_association *asoc, | |
5244 | const union sctp_subtype type, | |
5245 | void *arg, | |
5246 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5247 | { |
5248 | /* Stop the T5-shutdown guard timer. */ | |
5249 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5250 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5251 | ||
24cb81a6 | 5252 | return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5253 | } |
5254 | ||
5255 | /* | |
5256 | * sctp_sf_shutdown_sent_prm_abort | |
5257 | * | |
5258 | * Inputs | |
5259 | * (endpoint, asoc) | |
5260 | * | |
5261 | * The RFC does not explicitly address this issue, but is the route through the | |
5262 | * state table when someone issues an abort while in SHUTDOWN-SENT state. | |
5263 | * | |
5264 | * Outputs | |
5265 | * (timers) | |
5266 | */ | |
172a1599 XL |
5267 | enum sctp_disposition sctp_sf_shutdown_sent_prm_abort( |
5268 | struct net *net, | |
5269 | const struct sctp_endpoint *ep, | |
5270 | const struct sctp_association *asoc, | |
5271 | const union sctp_subtype type, | |
5272 | void *arg, | |
5273 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5274 | { |
5275 | /* Stop the T2-shutdown timer. */ | |
5276 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5277 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5278 | ||
5279 | /* Stop the T5-shutdown guard timer. */ | |
5280 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5281 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5282 | ||
24cb81a6 | 5283 | return sctp_sf_do_9_1_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5284 | } |
5285 | ||
5286 | /* | |
5287 | * sctp_sf_cookie_echoed_prm_abort | |
5288 | * | |
5289 | * Inputs | |
5290 | * (endpoint, asoc) | |
5291 | * | |
5292 | * The RFC does not explcitly address this issue, but is the route through the | |
5293 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
5294 | * | |
5295 | * Outputs | |
5296 | * (timers) | |
5297 | */ | |
172a1599 XL |
5298 | enum sctp_disposition sctp_sf_shutdown_ack_sent_prm_abort( |
5299 | struct net *net, | |
5300 | const struct sctp_endpoint *ep, | |
5301 | const struct sctp_association *asoc, | |
5302 | const union sctp_subtype type, | |
5303 | void *arg, | |
5304 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5305 | { |
5306 | /* The same T2 timer, so we should be able to use | |
5307 | * common function with the SHUTDOWN-SENT state. | |
5308 | */ | |
24cb81a6 | 5309 | return sctp_sf_shutdown_sent_prm_abort(net, ep, asoc, type, arg, commands); |
1da177e4 LT |
5310 | } |
5311 | ||
5312 | /* | |
5313 | * Process the REQUESTHEARTBEAT primitive | |
5314 | * | |
5315 | * 10.1 ULP-to-SCTP | |
5316 | * J) Request Heartbeat | |
5317 | * | |
5318 | * Format: REQUESTHEARTBEAT(association id, destination transport address) | |
5319 | * | |
5320 | * -> result | |
5321 | * | |
5322 | * Instructs the local endpoint to perform a HeartBeat on the specified | |
5323 | * destination transport address of the given association. The returned | |
5324 | * result should indicate whether the transmission of the HEARTBEAT | |
5325 | * chunk to the destination address is successful. | |
5326 | * | |
5327 | * Mandatory attributes: | |
5328 | * | |
5329 | * o association id - local handle to the SCTP association | |
5330 | * | |
5331 | * o destination transport address - the transport address of the | |
5332 | * association on which a heartbeat should be issued. | |
5333 | */ | |
172a1599 | 5334 | enum sctp_disposition sctp_sf_do_prm_requestheartbeat( |
24cb81a6 | 5335 | struct net *net, |
1da177e4 LT |
5336 | const struct sctp_endpoint *ep, |
5337 | const struct sctp_association *asoc, | |
bfc6f827 | 5338 | const union sctp_subtype type, |
1da177e4 | 5339 | void *arg, |
a85bbeb2 | 5340 | struct sctp_cmd_seq *commands) |
1da177e4 | 5341 | { |
fb78525a VY |
5342 | if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type, |
5343 | (struct sctp_transport *)arg, commands)) | |
5344 | return SCTP_DISPOSITION_NOMEM; | |
5345 | ||
5346 | /* | |
5347 | * RFC 2960 (bis), section 8.3 | |
5348 | * | |
5349 | * D) Request an on-demand HEARTBEAT on a specific destination | |
5350 | * transport address of a given association. | |
5351 | * | |
5352 | * The endpoint should increment the respective error counter of | |
5353 | * the destination transport address each time a HEARTBEAT is sent | |
5354 | * to that address and not acknowledged within one RTO. | |
5355 | * | |
5356 | */ | |
7e99013a | 5357 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
fb78525a VY |
5358 | SCTP_TRANSPORT(arg)); |
5359 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5360 | } |
5361 | ||
5362 | /* | |
5363 | * ADDIP Section 4.1 ASCONF Chunk Procedures | |
5364 | * When an endpoint has an ASCONF signaled change to be sent to the | |
5365 | * remote endpoint it should do A1 to A9 | |
5366 | */ | |
172a1599 XL |
5367 | enum sctp_disposition sctp_sf_do_prm_asconf(struct net *net, |
5368 | const struct sctp_endpoint *ep, | |
5369 | const struct sctp_association *asoc, | |
5370 | const union sctp_subtype type, | |
5371 | void *arg, | |
5372 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5373 | { |
5374 | struct sctp_chunk *chunk = arg; | |
5375 | ||
5376 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5377 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5378 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5379 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
5380 | return SCTP_DISPOSITION_CONSUME; | |
5381 | } | |
5382 | ||
7a090b04 | 5383 | /* RE-CONFIG Section 5.1 RECONF Chunk Procedures */ |
172a1599 XL |
5384 | enum sctp_disposition sctp_sf_do_prm_reconf(struct net *net, |
5385 | const struct sctp_endpoint *ep, | |
5386 | const struct sctp_association *asoc, | |
5387 | const union sctp_subtype type, | |
5388 | void *arg, | |
5389 | struct sctp_cmd_seq *commands) | |
7a090b04 XL |
5390 | { |
5391 | struct sctp_chunk *chunk = arg; | |
5392 | ||
5393 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
5394 | return SCTP_DISPOSITION_CONSUME; | |
5395 | } | |
5396 | ||
1da177e4 LT |
5397 | /* |
5398 | * Ignore the primitive event | |
5399 | * | |
5400 | * The return value is the disposition of the primitive. | |
5401 | */ | |
172a1599 XL |
5402 | enum sctp_disposition sctp_sf_ignore_primitive( |
5403 | struct net *net, | |
5404 | const struct sctp_endpoint *ep, | |
5405 | const struct sctp_association *asoc, | |
5406 | const union sctp_subtype type, | |
5407 | void *arg, | |
5408 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5409 | { |
bb33381d DB |
5410 | pr_debug("%s: primitive type:%d is ignored\n", __func__, |
5411 | type.primitive); | |
5412 | ||
1da177e4 LT |
5413 | return SCTP_DISPOSITION_DISCARD; |
5414 | } | |
5415 | ||
5416 | /*************************************************************************** | |
5417 | * These are the state functions for the OTHER events. | |
5418 | ***************************************************************************/ | |
5419 | ||
e1cdd553 WY |
5420 | /* |
5421 | * When the SCTP stack has no more user data to send or retransmit, this | |
5422 | * notification is given to the user. Also, at the time when a user app | |
5423 | * subscribes to this event, if there is no data to be sent or | |
5424 | * retransmit, the stack will immediately send up this notification. | |
5425 | */ | |
172a1599 XL |
5426 | enum sctp_disposition sctp_sf_do_no_pending_tsn( |
5427 | struct net *net, | |
5428 | const struct sctp_endpoint *ep, | |
5429 | const struct sctp_association *asoc, | |
5430 | const union sctp_subtype type, | |
5431 | void *arg, | |
5432 | struct sctp_cmd_seq *commands) | |
e1cdd553 WY |
5433 | { |
5434 | struct sctp_ulpevent *event; | |
5435 | ||
5436 | event = sctp_ulpevent_make_sender_dry_event(asoc, GFP_ATOMIC); | |
5437 | if (!event) | |
5438 | return SCTP_DISPOSITION_NOMEM; | |
5439 | ||
5440 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(event)); | |
5441 | ||
5442 | return SCTP_DISPOSITION_CONSUME; | |
5443 | } | |
5444 | ||
1da177e4 LT |
5445 | /* |
5446 | * Start the shutdown negotiation. | |
5447 | * | |
5448 | * From Section 9.2: | |
5449 | * Once all its outstanding data has been acknowledged, the endpoint | |
5450 | * shall send a SHUTDOWN chunk to its peer including in the Cumulative | |
5451 | * TSN Ack field the last sequential TSN it has received from the peer. | |
5452 | * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT | |
5453 | * state. If the timer expires, the endpoint must re-send the SHUTDOWN | |
5454 | * with the updated last sequential TSN received from its peer. | |
5455 | * | |
5456 | * The return value is the disposition. | |
5457 | */ | |
172a1599 XL |
5458 | enum sctp_disposition sctp_sf_do_9_2_start_shutdown( |
5459 | struct net *net, | |
5460 | const struct sctp_endpoint *ep, | |
5461 | const struct sctp_association *asoc, | |
5462 | const union sctp_subtype type, | |
5463 | void *arg, | |
5464 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5465 | { |
5466 | struct sctp_chunk *reply; | |
5467 | ||
5468 | /* Once all its outstanding data has been acknowledged, the | |
5469 | * endpoint shall send a SHUTDOWN chunk to its peer including | |
5470 | * in the Cumulative TSN Ack field the last sequential TSN it | |
5471 | * has received from the peer. | |
5472 | */ | |
5473 | reply = sctp_make_shutdown(asoc, NULL); | |
5474 | if (!reply) | |
5475 | goto nomem; | |
5476 | ||
5477 | /* Set the transport for the SHUTDOWN chunk and the timeout for the | |
5478 | * T2-shutdown timer. | |
5479 | */ | |
5480 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5481 | ||
5482 | /* It shall then start the T2-shutdown timer */ | |
5483 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5484 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5485 | ||
536428a9 WY |
5486 | /* RFC 4960 Section 9.2 |
5487 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5488 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5489 | */ | |
f8d96052 | 5490 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, |
536428a9 WY |
5491 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); |
5492 | ||
9f70f46b | 5493 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
5494 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
5495 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5496 | ||
5497 | /* and enter the SHUTDOWN-SENT state. */ | |
5498 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5499 | SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT)); | |
5500 | ||
5501 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5502 | * | |
5503 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5504 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5505 | */ |
5506 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5507 | ||
5508 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5509 | ||
5510 | return SCTP_DISPOSITION_CONSUME; | |
5511 | ||
5512 | nomem: | |
5513 | return SCTP_DISPOSITION_NOMEM; | |
5514 | } | |
5515 | ||
5516 | /* | |
5517 | * Generate a SHUTDOWN ACK now that everything is SACK'd. | |
5518 | * | |
5519 | * From Section 9.2: | |
5520 | * | |
5521 | * If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5522 | * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own, | |
5523 | * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the | |
5524 | * endpoint must re-send the SHUTDOWN ACK. | |
5525 | * | |
5526 | * The return value is the disposition. | |
5527 | */ | |
172a1599 XL |
5528 | enum sctp_disposition sctp_sf_do_9_2_shutdown_ack( |
5529 | struct net *net, | |
5530 | const struct sctp_endpoint *ep, | |
5531 | const struct sctp_association *asoc, | |
5532 | const union sctp_subtype type, | |
5533 | void *arg, | |
5534 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5535 | { |
172a1599 | 5536 | struct sctp_chunk *chunk = arg; |
1da177e4 LT |
5537 | struct sctp_chunk *reply; |
5538 | ||
5539 | /* There are 2 ways of getting here: | |
5540 | * 1) called in response to a SHUTDOWN chunk | |
5541 | * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued. | |
5542 | * | |
5543 | * For the case (2), the arg parameter is set to NULL. We need | |
5544 | * to check that we have a chunk before accessing it's fields. | |
5545 | */ | |
5546 | if (chunk) { | |
5547 | if (!sctp_vtag_verify(chunk, asoc)) | |
ac23e681 XL |
5548 | return sctp_sf_pdiscard(net, ep, asoc, type, arg, |
5549 | commands); | |
1da177e4 LT |
5550 | |
5551 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
ac23e681 XL |
5552 | if (!sctp_chunk_length_valid( |
5553 | chunk, sizeof(struct sctp_shutdown_chunk))) | |
5554 | return sctp_sf_violation_chunklen(net, ep, asoc, type, | |
5555 | arg, commands); | |
1da177e4 LT |
5556 | } |
5557 | ||
5558 | /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5559 | * shall send a SHUTDOWN ACK ... | |
5560 | */ | |
5561 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
5562 | if (!reply) | |
5563 | goto nomem; | |
5564 | ||
5565 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
5566 | * the T2-shutdown timer. | |
5567 | */ | |
5568 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5569 | ||
5570 | /* and start/restart a T2-shutdown timer of its own, */ | |
5571 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5572 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5573 | ||
9f70f46b | 5574 | if (asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE]) |
1da177e4 LT |
5575 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, |
5576 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5577 | ||
5578 | /* Enter the SHUTDOWN-ACK-SENT state. */ | |
5579 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5580 | SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT)); | |
5581 | ||
5582 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5583 | * | |
5584 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5585 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5586 | */ |
5587 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5588 | ||
5589 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5590 | ||
5591 | return SCTP_DISPOSITION_CONSUME; | |
5592 | ||
5593 | nomem: | |
5594 | return SCTP_DISPOSITION_NOMEM; | |
5595 | } | |
5596 | ||
5597 | /* | |
5598 | * Ignore the event defined as other | |
5599 | * | |
5600 | * The return value is the disposition of the event. | |
5601 | */ | |
172a1599 XL |
5602 | enum sctp_disposition sctp_sf_ignore_other(struct net *net, |
5603 | const struct sctp_endpoint *ep, | |
5604 | const struct sctp_association *asoc, | |
5605 | const union sctp_subtype type, | |
5606 | void *arg, | |
5607 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5608 | { |
bb33381d DB |
5609 | pr_debug("%s: the event other type:%d is ignored\n", |
5610 | __func__, type.other); | |
5611 | ||
1da177e4 LT |
5612 | return SCTP_DISPOSITION_DISCARD; |
5613 | } | |
5614 | ||
5615 | /************************************************************ | |
5616 | * These are the state functions for handling timeout events. | |
5617 | ************************************************************/ | |
5618 | ||
5619 | /* | |
5620 | * RTX Timeout | |
5621 | * | |
5622 | * Section: 6.3.3 Handle T3-rtx Expiration | |
5623 | * | |
5624 | * Whenever the retransmission timer T3-rtx expires for a destination | |
5625 | * address, do the following: | |
5626 | * [See below] | |
5627 | * | |
5628 | * The return value is the disposition of the chunk. | |
5629 | */ | |
172a1599 XL |
5630 | enum sctp_disposition sctp_sf_do_6_3_3_rtx(struct net *net, |
5631 | const struct sctp_endpoint *ep, | |
5632 | const struct sctp_association *asoc, | |
5633 | const union sctp_subtype type, | |
5634 | void *arg, | |
5635 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5636 | { |
5637 | struct sctp_transport *transport = arg; | |
5638 | ||
b01a2407 | 5639 | SCTP_INC_STATS(net, SCTP_MIB_T3_RTX_EXPIREDS); |
ac0b0462 | 5640 | |
1da177e4 | 5641 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8a0d19c5 | 5642 | if (asoc->peer.zero_window_announced && |
5643 | asoc->state == SCTP_STATE_SHUTDOWN_PENDING) { | |
f8d96052 TG |
5644 | /* |
5645 | * We are here likely because the receiver had its rwnd | |
5646 | * closed for a while and we have not been able to | |
5647 | * transmit the locally queued data within the maximum | |
5648 | * retransmission attempts limit. Start the T5 | |
5649 | * shutdown guard timer to give the receiver one last | |
5650 | * chance and some additional time to recover before | |
5651 | * aborting. | |
5652 | */ | |
5653 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START_ONCE, | |
5654 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5655 | } else { | |
5656 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
5657 | SCTP_ERROR(ETIMEDOUT)); | |
5658 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ | |
5659 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5660 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); | |
b01a2407 EB |
5661 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5662 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
f8d96052 TG |
5663 | return SCTP_DISPOSITION_DELETE_TCB; |
5664 | } | |
1da177e4 LT |
5665 | } |
5666 | ||
5667 | /* E1) For the destination address for which the timer | |
5668 | * expires, adjust its ssthresh with rules defined in Section | |
5669 | * 7.2.3 and set the cwnd <- MTU. | |
5670 | */ | |
5671 | ||
5672 | /* E2) For the destination address for which the timer | |
5673 | * expires, set RTO <- RTO * 2 ("back off the timer"). The | |
5674 | * maximum value discussed in rule C7 above (RTO.max) may be | |
5675 | * used to provide an upper bound to this doubling operation. | |
5676 | */ | |
5677 | ||
5678 | /* E3) Determine how many of the earliest (i.e., lowest TSN) | |
5679 | * outstanding DATA chunks for the address for which the | |
5680 | * T3-rtx has expired will fit into a single packet, subject | |
5681 | * to the MTU constraint for the path corresponding to the | |
5682 | * destination transport address to which the retransmission | |
5683 | * is being sent (this may be different from the address for | |
5684 | * which the timer expires [see Section 6.4]). Call this | |
5685 | * value K. Bundle and retransmit those K DATA chunks in a | |
5686 | * single packet to the destination endpoint. | |
5687 | * | |
5688 | * Note: Any DATA chunks that were sent to the address for | |
5689 | * which the T3-rtx timer expired but did not fit in one MTU | |
5690 | * (rule E3 above), should be marked for retransmission and | |
5691 | * sent as soon as cwnd allows (normally when a SACK arrives). | |
5692 | */ | |
5693 | ||
1da177e4 LT |
5694 | /* Do some failure management (Section 8.2). */ |
5695 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5696 | ||
1845a579 VY |
5697 | /* NB: Rules E4 and F1 are implicit in R1. */ |
5698 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport)); | |
5699 | ||
1da177e4 LT |
5700 | return SCTP_DISPOSITION_CONSUME; |
5701 | } | |
5702 | ||
5703 | /* | |
5704 | * Generate delayed SACK on timeout | |
5705 | * | |
5706 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
5707 | * | |
5708 | * The guidelines on delayed acknowledgement algorithm specified in | |
5709 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
5710 | * acknowledgement SHOULD be generated for at least every second packet | |
5711 | * (not every second DATA chunk) received, and SHOULD be generated | |
5712 | * within 200 ms of the arrival of any unacknowledged DATA chunk. In | |
5713 | * some situations it may be beneficial for an SCTP transmitter to be | |
5714 | * more conservative than the algorithms detailed in this document | |
5715 | * allow. However, an SCTP transmitter MUST NOT be more aggressive than | |
5716 | * the following algorithms allow. | |
5717 | */ | |
172a1599 XL |
5718 | enum sctp_disposition sctp_sf_do_6_2_sack(struct net *net, |
5719 | const struct sctp_endpoint *ep, | |
5720 | const struct sctp_association *asoc, | |
5721 | const union sctp_subtype type, | |
5722 | void *arg, | |
5723 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5724 | { |
b01a2407 | 5725 | SCTP_INC_STATS(net, SCTP_MIB_DELAY_SACK_EXPIREDS); |
1da177e4 LT |
5726 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); |
5727 | return SCTP_DISPOSITION_CONSUME; | |
5728 | } | |
5729 | ||
5730 | /* | |
3f7a87d2 | 5731 | * sctp_sf_t1_init_timer_expire |
1da177e4 LT |
5732 | * |
5733 | * Section: 4 Note: 2 | |
5734 | * Verification Tag: | |
5735 | * Inputs | |
5736 | * (endpoint, asoc) | |
5737 | * | |
5738 | * RFC 2960 Section 4 Notes | |
5739 | * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT | |
5740 | * and re-start the T1-init timer without changing state. This MUST | |
5741 | * be repeated up to 'Max.Init.Retransmits' times. After that, the | |
5742 | * endpoint MUST abort the initialization process and report the | |
5743 | * error to SCTP user. | |
5744 | * | |
3f7a87d2 FF |
5745 | * Outputs |
5746 | * (timers, events) | |
5747 | * | |
5748 | */ | |
172a1599 XL |
5749 | enum sctp_disposition sctp_sf_t1_init_timer_expire( |
5750 | struct net *net, | |
5751 | const struct sctp_endpoint *ep, | |
5752 | const struct sctp_association *asoc, | |
5753 | const union sctp_subtype type, | |
5754 | void *arg, | |
5755 | struct sctp_cmd_seq *commands) | |
3f7a87d2 | 5756 | { |
172a1599 | 5757 | int attempts = asoc->init_err_counter + 1; |
3f7a87d2 FF |
5758 | struct sctp_chunk *repl = NULL; |
5759 | struct sctp_bind_addr *bp; | |
3f7a87d2 | 5760 | |
bb33381d DB |
5761 | pr_debug("%s: timer T1 expired (INIT)\n", __func__); |
5762 | ||
b01a2407 | 5763 | SCTP_INC_STATS(net, SCTP_MIB_T1_INIT_EXPIREDS); |
3f7a87d2 | 5764 | |
81845c21 | 5765 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 FF |
5766 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; |
5767 | repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0); | |
5768 | if (!repl) | |
5769 | return SCTP_DISPOSITION_NOMEM; | |
5770 | ||
5771 | /* Choose transport for INIT. */ | |
5772 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
5773 | SCTP_CHUNK(repl)); | |
5774 | ||
5775 | /* Issue a sideeffect to do the needed accounting. */ | |
5776 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART, | |
5777 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
5778 | ||
5779 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
5780 | } else { | |
bb33381d DB |
5781 | pr_debug("%s: giving up on INIT, attempts:%d " |
5782 | "max_init_attempts:%d\n", __func__, attempts, | |
5783 | asoc->max_init_attempts); | |
5784 | ||
8de8c873 SS |
5785 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5786 | SCTP_ERROR(ETIMEDOUT)); | |
3f7a87d2 | 5787 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5788 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
3f7a87d2 FF |
5789 | return SCTP_DISPOSITION_DELETE_TCB; |
5790 | } | |
5791 | ||
5792 | return SCTP_DISPOSITION_CONSUME; | |
5793 | } | |
5794 | ||
5795 | /* | |
5796 | * sctp_sf_t1_cookie_timer_expire | |
5797 | * | |
5798 | * Section: 4 Note: 2 | |
5799 | * Verification Tag: | |
5800 | * Inputs | |
5801 | * (endpoint, asoc) | |
5802 | * | |
5803 | * RFC 2960 Section 4 Notes | |
5804 | * 3) If the T1-cookie timer expires, the endpoint MUST retransmit | |
1da177e4 LT |
5805 | * COOKIE ECHO and re-start the T1-cookie timer without changing |
5806 | * state. This MUST be repeated up to 'Max.Init.Retransmits' times. | |
5807 | * After that, the endpoint MUST abort the initialization process and | |
5808 | * report the error to SCTP user. | |
5809 | * | |
5810 | * Outputs | |
5811 | * (timers, events) | |
5812 | * | |
5813 | */ | |
172a1599 XL |
5814 | enum sctp_disposition sctp_sf_t1_cookie_timer_expire( |
5815 | struct net *net, | |
5816 | const struct sctp_endpoint *ep, | |
5817 | const struct sctp_association *asoc, | |
5818 | const union sctp_subtype type, | |
5819 | void *arg, | |
5820 | struct sctp_cmd_seq *commands) | |
1da177e4 | 5821 | { |
3f7a87d2 | 5822 | int attempts = asoc->init_err_counter + 1; |
172a1599 | 5823 | struct sctp_chunk *repl = NULL; |
1da177e4 | 5824 | |
bb33381d DB |
5825 | pr_debug("%s: timer T1 expired (COOKIE-ECHO)\n", __func__); |
5826 | ||
b01a2407 | 5827 | SCTP_INC_STATS(net, SCTP_MIB_T1_COOKIE_EXPIREDS); |
1da177e4 | 5828 | |
81845c21 | 5829 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 | 5830 | repl = sctp_make_cookie_echo(asoc, NULL); |
1da177e4 | 5831 | if (!repl) |
3f7a87d2 | 5832 | return SCTP_DISPOSITION_NOMEM; |
1da177e4 | 5833 | |
96cd0d3d VY |
5834 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, |
5835 | SCTP_CHUNK(repl)); | |
1da177e4 | 5836 | /* Issue a sideeffect to do the needed accounting. */ |
3f7a87d2 FF |
5837 | sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART, |
5838 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
5839 | ||
1da177e4 LT |
5840 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
5841 | } else { | |
8de8c873 SS |
5842 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5843 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5844 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5845 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5846 | return SCTP_DISPOSITION_DELETE_TCB; |
5847 | } | |
5848 | ||
5849 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5850 | } |
5851 | ||
5852 | /* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN | |
5853 | * with the updated last sequential TSN received from its peer. | |
5854 | * | |
5855 | * An endpoint should limit the number of retransmissions of the | |
5856 | * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'. | |
5857 | * If this threshold is exceeded the endpoint should destroy the TCB and | |
5858 | * MUST report the peer endpoint unreachable to the upper layer (and | |
5859 | * thus the association enters the CLOSED state). The reception of any | |
5860 | * packet from its peer (i.e. as the peer sends all of its queued DATA | |
5861 | * chunks) should clear the endpoint's retransmission count and restart | |
5862 | * the T2-Shutdown timer, giving its peer ample opportunity to transmit | |
5863 | * all of its queued DATA chunks that have not yet been sent. | |
5864 | */ | |
172a1599 XL |
5865 | enum sctp_disposition sctp_sf_t2_timer_expire( |
5866 | struct net *net, | |
5867 | const struct sctp_endpoint *ep, | |
5868 | const struct sctp_association *asoc, | |
5869 | const union sctp_subtype type, | |
5870 | void *arg, | |
5871 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5872 | { |
5873 | struct sctp_chunk *reply = NULL; | |
5874 | ||
bb33381d DB |
5875 | pr_debug("%s: timer T2 expired\n", __func__); |
5876 | ||
b01a2407 | 5877 | SCTP_INC_STATS(net, SCTP_MIB_T2_SHUTDOWN_EXPIREDS); |
ac0b0462 | 5878 | |
58fbbed4 NH |
5879 | ((struct sctp_association *)asoc)->shutdown_retries++; |
5880 | ||
1da177e4 | 5881 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5882 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5883 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5884 | /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5885 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5886 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
5887 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5888 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
5889 | return SCTP_DISPOSITION_DELETE_TCB; |
5890 | } | |
5891 | ||
5892 | switch (asoc->state) { | |
5893 | case SCTP_STATE_SHUTDOWN_SENT: | |
5894 | reply = sctp_make_shutdown(asoc, NULL); | |
5895 | break; | |
5896 | ||
5897 | case SCTP_STATE_SHUTDOWN_ACK_SENT: | |
5898 | reply = sctp_make_shutdown_ack(asoc, NULL); | |
5899 | break; | |
5900 | ||
5901 | default: | |
5902 | BUG(); | |
5903 | break; | |
3ff50b79 | 5904 | } |
1da177e4 LT |
5905 | |
5906 | if (!reply) | |
5907 | goto nomem; | |
5908 | ||
6345b199 WY |
5909 | /* Do some failure management (Section 8.2). |
5910 | * If we remove the transport an SHUTDOWN was last sent to, don't | |
5911 | * do failure management. | |
5912 | */ | |
5913 | if (asoc->shutdown_last_sent_to) | |
5914 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5915 | SCTP_TRANSPORT(asoc->shutdown_last_sent_to)); | |
1da177e4 LT |
5916 | |
5917 | /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for | |
5918 | * the T2-shutdown timer. | |
5919 | */ | |
5920 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5921 | ||
5922 | /* Restart the T2-shutdown timer. */ | |
5923 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5924 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5925 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5926 | return SCTP_DISPOSITION_CONSUME; | |
5927 | ||
5928 | nomem: | |
5929 | return SCTP_DISPOSITION_NOMEM; | |
5930 | } | |
5931 | ||
5932 | /* | |
5933 | * ADDIP Section 4.1 ASCONF CHunk Procedures | |
5934 | * If the T4 RTO timer expires the endpoint should do B1 to B5 | |
5935 | */ | |
172a1599 XL |
5936 | enum sctp_disposition sctp_sf_t4_timer_expire( |
5937 | struct net *net, | |
5938 | const struct sctp_endpoint *ep, | |
5939 | const struct sctp_association *asoc, | |
5940 | const union sctp_subtype type, | |
5941 | void *arg, | |
5942 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
5943 | { |
5944 | struct sctp_chunk *chunk = asoc->addip_last_asconf; | |
5945 | struct sctp_transport *transport = chunk->transport; | |
5946 | ||
b01a2407 | 5947 | SCTP_INC_STATS(net, SCTP_MIB_T4_RTO_EXPIREDS); |
ac0b0462 | 5948 | |
1da177e4 LT |
5949 | /* ADDIP 4.1 B1) Increment the error counters and perform path failure |
5950 | * detection on the appropriate destination address as defined in | |
5951 | * RFC2960 [5] section 8.1 and 8.2. | |
5952 | */ | |
10a43cea WY |
5953 | if (transport) |
5954 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5955 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
5956 | |
5957 | /* Reconfig T4 timer and transport. */ | |
5958 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5959 | ||
5960 | /* ADDIP 4.1 B2) Increment the association error counters and perform | |
5961 | * endpoint failure detection on the association as defined in | |
5962 | * RFC2960 [5] section 8.1 and 8.2. | |
5963 | * association error counter is incremented in SCTP_CMD_STRIKE. | |
5964 | */ | |
5965 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
5966 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5967 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
8de8c873 SS |
5968 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5969 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5970 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5971 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
b01a2407 EB |
5972 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
5973 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
5974 | return SCTP_DISPOSITION_ABORT; |
5975 | } | |
5976 | ||
5977 | /* ADDIP 4.1 B3) Back-off the destination address RTO value to which | |
5978 | * the ASCONF chunk was sent by doubling the RTO timer value. | |
5979 | * This is done in SCTP_CMD_STRIKE. | |
5980 | */ | |
5981 | ||
5982 | /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible | |
5983 | * choose an alternate destination address (please refer to RFC2960 | |
5984 | * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this | |
d808ad9a | 5985 | * chunk, it MUST be the same (including its serial number) as the last |
1da177e4 LT |
5986 | * ASCONF sent. |
5987 | */ | |
5988 | sctp_chunk_hold(asoc->addip_last_asconf); | |
5989 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5990 | SCTP_CHUNK(asoc->addip_last_asconf)); | |
5991 | ||
5992 | /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different | |
5993 | * destination is selected, then the RTO used will be that of the new | |
5994 | * destination address. | |
5995 | */ | |
5996 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5997 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5998 | ||
5999 | return SCTP_DISPOSITION_CONSUME; | |
6000 | } | |
6001 | ||
6002 | /* sctpimpguide-05 Section 2.12.2 | |
6003 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
6004 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
6005 | * At the expiration of this timer the sender SHOULD abort the association | |
6006 | * by sending an ABORT chunk. | |
6007 | */ | |
172a1599 XL |
6008 | enum sctp_disposition sctp_sf_t5_timer_expire( |
6009 | struct net *net, | |
6010 | const struct sctp_endpoint *ep, | |
6011 | const struct sctp_association *asoc, | |
6012 | const union sctp_subtype type, | |
6013 | void *arg, | |
6014 | struct sctp_cmd_seq *commands) | |
1da177e4 LT |
6015 | { |
6016 | struct sctp_chunk *reply = NULL; | |
6017 | ||
bb33381d DB |
6018 | pr_debug("%s: timer T5 expired\n", __func__); |
6019 | ||
b01a2407 | 6020 | SCTP_INC_STATS(net, SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS); |
1da177e4 LT |
6021 | |
6022 | reply = sctp_make_abort(asoc, NULL, 0); | |
6023 | if (!reply) | |
6024 | goto nomem; | |
6025 | ||
6026 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
8de8c873 SS |
6027 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
6028 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 6029 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 6030 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 | 6031 | |
b01a2407 EB |
6032 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
6033 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
a1080a8b | 6034 | |
1da177e4 LT |
6035 | return SCTP_DISPOSITION_DELETE_TCB; |
6036 | nomem: | |
6037 | return SCTP_DISPOSITION_NOMEM; | |
6038 | } | |
6039 | ||
6040 | /* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires, | |
6041 | * the association is automatically closed by starting the shutdown process. | |
6042 | * The work that needs to be done is same as when SHUTDOWN is initiated by | |
6043 | * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown(). | |
6044 | */ | |
172a1599 XL |
6045 | enum sctp_disposition sctp_sf_autoclose_timer_expire( |
6046 | struct net *net, | |
6047 | const struct sctp_endpoint *ep, | |
6048 | const struct sctp_association *asoc, | |
6049 | const union sctp_subtype type, | |
6050 | void *arg, | |
6051 | struct sctp_cmd_seq *commands) | |
1da177e4 | 6052 | { |
172a1599 | 6053 | enum sctp_disposition disposition; |
1da177e4 | 6054 | |
b01a2407 | 6055 | SCTP_INC_STATS(net, SCTP_MIB_AUTOCLOSE_EXPIREDS); |
ac0b0462 | 6056 | |
1da177e4 LT |
6057 | /* From 9.2 Shutdown of an Association |
6058 | * Upon receipt of the SHUTDOWN primitive from its upper | |
6059 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
6060 | * remains there until all outstanding data has been | |
6061 | * acknowledged by its peer. The endpoint accepts no new data | |
6062 | * from its upper layer, but retransmits data to the far end | |
6063 | * if necessary to fill gaps. | |
6064 | */ | |
6065 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
6066 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
6067 | ||
1da177e4 LT |
6068 | disposition = SCTP_DISPOSITION_CONSUME; |
6069 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
24cb81a6 | 6070 | disposition = sctp_sf_do_9_2_start_shutdown(net, ep, asoc, type, |
1da177e4 LT |
6071 | arg, commands); |
6072 | } | |
172a1599 | 6073 | |
1da177e4 LT |
6074 | return disposition; |
6075 | } | |
6076 | ||
6077 | /***************************************************************************** | |
6078 | * These are sa state functions which could apply to all types of events. | |
6079 | ****************************************************************************/ | |
6080 | ||
6081 | /* | |
6082 | * This table entry is not implemented. | |
6083 | * | |
6084 | * Inputs | |
6085 | * (endpoint, asoc, chunk) | |
6086 | * | |
6087 | * The return value is the disposition of the chunk. | |
6088 | */ | |
172a1599 XL |
6089 | enum sctp_disposition sctp_sf_not_impl(struct net *net, |
6090 | const struct sctp_endpoint *ep, | |
6091 | const struct sctp_association *asoc, | |
6092 | const union sctp_subtype type, | |
6093 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 LT |
6094 | { |
6095 | return SCTP_DISPOSITION_NOT_IMPL; | |
6096 | } | |
6097 | ||
6098 | /* | |
6099 | * This table entry represents a bug. | |
6100 | * | |
6101 | * Inputs | |
6102 | * (endpoint, asoc, chunk) | |
6103 | * | |
6104 | * The return value is the disposition of the chunk. | |
6105 | */ | |
172a1599 XL |
6106 | enum sctp_disposition sctp_sf_bug(struct net *net, |
6107 | const struct sctp_endpoint *ep, | |
6108 | const struct sctp_association *asoc, | |
6109 | const union sctp_subtype type, | |
6110 | void *arg, struct sctp_cmd_seq *commands) | |
1da177e4 LT |
6111 | { |
6112 | return SCTP_DISPOSITION_BUG; | |
6113 | } | |
6114 | ||
6115 | /* | |
6116 | * This table entry represents the firing of a timer in the wrong state. | |
6117 | * Since timer deletion cannot be guaranteed a timer 'may' end up firing | |
6118 | * when the association is in the wrong state. This event should | |
6119 | * be ignored, so as to prevent any rearming of the timer. | |
6120 | * | |
6121 | * Inputs | |
6122 | * (endpoint, asoc, chunk) | |
6123 | * | |
6124 | * The return value is the disposition of the chunk. | |
6125 | */ | |
172a1599 XL |
6126 | enum sctp_disposition sctp_sf_timer_ignore(struct net *net, |
6127 | const struct sctp_endpoint *ep, | |
6128 | const struct sctp_association *asoc, | |
6129 | const union sctp_subtype type, | |
6130 | void *arg, | |
6131 | struct sctp_cmd_seq *commands) | |
1da177e4 | 6132 | { |
bb33381d DB |
6133 | pr_debug("%s: timer %d ignored\n", __func__, type.chunk); |
6134 | ||
1da177e4 LT |
6135 | return SCTP_DISPOSITION_CONSUME; |
6136 | } | |
6137 | ||
6138 | /******************************************************************** | |
6139 | * 2nd Level Abstractions | |
6140 | ********************************************************************/ | |
6141 | ||
6142 | /* Pull the SACK chunk based on the SACK header. */ | |
6143 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk) | |
6144 | { | |
6145 | struct sctp_sackhdr *sack; | |
172a1599 | 6146 | __u16 num_dup_tsns; |
1da177e4 LT |
6147 | unsigned int len; |
6148 | __u16 num_blocks; | |
1da177e4 LT |
6149 | |
6150 | /* Protect ourselves from reading too far into | |
6151 | * the skb from a bogus sender. | |
6152 | */ | |
6153 | sack = (struct sctp_sackhdr *) chunk->skb->data; | |
6154 | ||
6155 | num_blocks = ntohs(sack->num_gap_ack_blocks); | |
6156 | num_dup_tsns = ntohs(sack->num_dup_tsns); | |
6157 | len = sizeof(struct sctp_sackhdr); | |
6158 | len += (num_blocks + num_dup_tsns) * sizeof(__u32); | |
6159 | if (len > chunk->skb->len) | |
6160 | return NULL; | |
6161 | ||
6162 | skb_pull(chunk->skb, len); | |
6163 | ||
6164 | return sack; | |
6165 | } | |
6166 | ||
6167 | /* Create an ABORT packet to be sent as a response, with the specified | |
6168 | * error causes. | |
6169 | */ | |
172a1599 XL |
6170 | static struct sctp_packet *sctp_abort_pkt_new( |
6171 | struct net *net, | |
6172 | const struct sctp_endpoint *ep, | |
6173 | const struct sctp_association *asoc, | |
6174 | struct sctp_chunk *chunk, | |
6175 | const void *payload, size_t paylen) | |
1da177e4 LT |
6176 | { |
6177 | struct sctp_packet *packet; | |
6178 | struct sctp_chunk *abort; | |
6179 | ||
2ce95503 | 6180 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
6181 | |
6182 | if (packet) { | |
6183 | /* Make an ABORT. | |
6184 | * The T bit will be set if the asoc is NULL. | |
6185 | */ | |
6186 | abort = sctp_make_abort(asoc, chunk, paylen); | |
6187 | if (!abort) { | |
6188 | sctp_ootb_pkt_free(packet); | |
6189 | return NULL; | |
6190 | } | |
047a2428 JF |
6191 | |
6192 | /* Reflect vtag if T-Bit is set */ | |
6193 | if (sctp_test_T_bit(abort)) | |
6194 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
6195 | ||
1da177e4 LT |
6196 | /* Add specified error causes, i.e., payload, to the |
6197 | * end of the chunk. | |
6198 | */ | |
6199 | sctp_addto_chunk(abort, paylen, payload); | |
6200 | ||
6201 | /* Set the skb to the belonging sock for accounting. */ | |
6202 | abort->skb->sk = ep->base.sk; | |
6203 | ||
6204 | sctp_packet_append_chunk(packet, abort); | |
6205 | ||
6206 | } | |
6207 | ||
6208 | return packet; | |
6209 | } | |
6210 | ||
6211 | /* Allocate a packet for responding in the OOTB conditions. */ | |
172a1599 XL |
6212 | static struct sctp_packet *sctp_ootb_pkt_new( |
6213 | struct net *net, | |
6214 | const struct sctp_association *asoc, | |
6215 | const struct sctp_chunk *chunk) | |
1da177e4 | 6216 | { |
1da177e4 | 6217 | struct sctp_transport *transport; |
172a1599 XL |
6218 | struct sctp_packet *packet; |
6219 | __u16 sport, dport; | |
1da177e4 LT |
6220 | __u32 vtag; |
6221 | ||
6222 | /* Get the source and destination port from the inbound packet. */ | |
6223 | sport = ntohs(chunk->sctp_hdr->dest); | |
6224 | dport = ntohs(chunk->sctp_hdr->source); | |
6225 | ||
6226 | /* The V-tag is going to be the same as the inbound packet if no | |
6227 | * association exists, otherwise, use the peer's vtag. | |
6228 | */ | |
6229 | if (asoc) { | |
02c4e12c WY |
6230 | /* Special case the INIT-ACK as there is no peer's vtag |
6231 | * yet. | |
6232 | */ | |
cb3f837b | 6233 | switch (chunk->chunk_hdr->type) { |
02c4e12c WY |
6234 | case SCTP_CID_INIT_ACK: |
6235 | { | |
cb1844c4 | 6236 | struct sctp_initack_chunk *initack; |
02c4e12c | 6237 | |
cb1844c4 | 6238 | initack = (struct sctp_initack_chunk *)chunk->chunk_hdr; |
02c4e12c WY |
6239 | vtag = ntohl(initack->init_hdr.init_tag); |
6240 | break; | |
6241 | } | |
6242 | default: | |
6243 | vtag = asoc->peer.i.init_tag; | |
6244 | break; | |
6245 | } | |
1da177e4 LT |
6246 | } else { |
6247 | /* Special case the INIT and stale COOKIE_ECHO as there is no | |
6248 | * vtag yet. | |
6249 | */ | |
cb3f837b | 6250 | switch (chunk->chunk_hdr->type) { |
1da177e4 LT |
6251 | case SCTP_CID_INIT: |
6252 | { | |
01a992be | 6253 | struct sctp_init_chunk *init; |
1da177e4 | 6254 | |
01a992be | 6255 | init = (struct sctp_init_chunk *)chunk->chunk_hdr; |
1da177e4 LT |
6256 | vtag = ntohl(init->init_hdr.init_tag); |
6257 | break; | |
6258 | } | |
d808ad9a | 6259 | default: |
1da177e4 LT |
6260 | vtag = ntohl(chunk->sctp_hdr->vtag); |
6261 | break; | |
6262 | } | |
6263 | } | |
6264 | ||
6265 | /* Make a transport for the bucket, Eliza... */ | |
89bf3450 | 6266 | transport = sctp_transport_new(net, sctp_source(chunk), GFP_ATOMIC); |
1da177e4 LT |
6267 | if (!transport) |
6268 | goto nomem; | |
6269 | ||
6270 | /* Cache a route for the transport with the chunk's destination as | |
6271 | * the source address. | |
6272 | */ | |
16b0a030 | 6273 | sctp_transport_route(transport, (union sctp_addr *)&chunk->dest, |
2ce95503 | 6274 | sctp_sk(net->sctp.ctl_sock)); |
1da177e4 | 6275 | |
66b91d2c MRL |
6276 | packet = &transport->packet; |
6277 | sctp_packet_init(packet, transport, sport, dport); | |
6278 | sctp_packet_config(packet, vtag, 0); | |
1da177e4 LT |
6279 | |
6280 | return packet; | |
6281 | ||
6282 | nomem: | |
6283 | return NULL; | |
6284 | } | |
6285 | ||
6286 | /* Free the packet allocated earlier for responding in the OOTB condition. */ | |
6287 | void sctp_ootb_pkt_free(struct sctp_packet *packet) | |
6288 | { | |
6289 | sctp_transport_free(packet->transport); | |
6290 | } | |
6291 | ||
6292 | /* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */ | |
24cb81a6 EB |
6293 | static void sctp_send_stale_cookie_err(struct net *net, |
6294 | const struct sctp_endpoint *ep, | |
1da177e4 LT |
6295 | const struct sctp_association *asoc, |
6296 | const struct sctp_chunk *chunk, | |
a85bbeb2 | 6297 | struct sctp_cmd_seq *commands, |
1da177e4 LT |
6298 | struct sctp_chunk *err_chunk) |
6299 | { | |
6300 | struct sctp_packet *packet; | |
6301 | ||
6302 | if (err_chunk) { | |
2ce95503 | 6303 | packet = sctp_ootb_pkt_new(net, asoc, chunk); |
1da177e4 LT |
6304 | if (packet) { |
6305 | struct sctp_signed_cookie *cookie; | |
6306 | ||
6307 | /* Override the OOTB vtag from the cookie. */ | |
6308 | cookie = chunk->subh.cookie_hdr; | |
6309 | packet->vtag = cookie->c.peer_vtag; | |
d808ad9a | 6310 | |
1da177e4 LT |
6311 | /* Set the skb to the belonging sock for accounting. */ |
6312 | err_chunk->skb->sk = ep->base.sk; | |
6313 | sctp_packet_append_chunk(packet, err_chunk); | |
6314 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
6315 | SCTP_PACKET(packet)); | |
b01a2407 | 6316 | SCTP_INC_STATS(net, SCTP_MIB_OUTCTRLCHUNKS); |
1da177e4 LT |
6317 | } else |
6318 | sctp_chunk_free (err_chunk); | |
6319 | } | |
6320 | } | |
6321 | ||
6322 | ||
6323 | /* Process a data chunk */ | |
6324 | static int sctp_eat_data(const struct sctp_association *asoc, | |
6325 | struct sctp_chunk *chunk, | |
a85bbeb2 | 6326 | struct sctp_cmd_seq *commands) |
1da177e4 | 6327 | { |
7c3ceb4f | 6328 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
049b3ff5 | 6329 | struct sock *sk = asoc->base.sk; |
24cb81a6 | 6330 | struct net *net = sock_net(sk); |
172a1599 XL |
6331 | struct sctp_datahdr *data_hdr; |
6332 | struct sctp_chunk *err; | |
6333 | enum sctp_verb deliver; | |
6334 | size_t datalen; | |
172a1599 XL |
6335 | __u32 tsn; |
6336 | int tmp; | |
1da177e4 | 6337 | |
3583df1a XL |
6338 | data_hdr = (struct sctp_datahdr *)chunk->skb->data; |
6339 | chunk->subh.data_hdr = data_hdr; | |
9d4ceaf1 | 6340 | skb_pull(chunk->skb, sctp_datahdr_len(&asoc->stream)); |
1da177e4 LT |
6341 | |
6342 | tsn = ntohl(data_hdr->tsn); | |
bb33381d | 6343 | pr_debug("%s: TSN 0x%x\n", __func__, tsn); |
1da177e4 LT |
6344 | |
6345 | /* ASSERT: Now skb->data is really the user data. */ | |
6346 | ||
6347 | /* Process ECN based congestion. | |
6348 | * | |
6349 | * Since the chunk structure is reused for all chunks within | |
6350 | * a packet, we use ecn_ce_done to track if we've already | |
6351 | * done CE processing for this packet. | |
6352 | * | |
6353 | * We need to do ECN processing even if we plan to discard the | |
6354 | * chunk later. | |
6355 | */ | |
6356 | ||
2d47fd12 | 6357 | if (asoc->peer.ecn_capable && !chunk->ecn_ce_done) { |
e7487c86 | 6358 | struct sctp_af *af = SCTP_INPUT_CB(chunk->skb)->af; |
1da177e4 LT |
6359 | chunk->ecn_ce_done = 1; |
6360 | ||
2d47fd12 | 6361 | if (af->is_ce(sctp_gso_headskb(chunk->skb))) { |
1da177e4 LT |
6362 | /* Do real work as sideffect. */ |
6363 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE, | |
6364 | SCTP_U32(tsn)); | |
6365 | } | |
6366 | } | |
6367 | ||
6368 | tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn); | |
6369 | if (tmp < 0) { | |
6370 | /* The TSN is too high--silently discard the chunk and | |
6371 | * count on it getting retransmitted later. | |
6372 | */ | |
196d6759 MB |
6373 | if (chunk->asoc) |
6374 | chunk->asoc->stats.outofseqtsns++; | |
1da177e4 LT |
6375 | return SCTP_IERROR_HIGH_TSN; |
6376 | } else if (tmp > 0) { | |
6377 | /* This is a duplicate. Record it. */ | |
6378 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn)); | |
6379 | return SCTP_IERROR_DUP_TSN; | |
6380 | } | |
6381 | ||
6382 | /* This is a new TSN. */ | |
6383 | ||
6384 | /* Discard if there is no room in the receive window. | |
6385 | * Actually, allow a little bit of overflow (up to a MTU). | |
6386 | */ | |
6387 | datalen = ntohs(chunk->chunk_hdr->length); | |
9d4ceaf1 | 6388 | datalen -= sctp_datachk_len(&asoc->stream); |
1da177e4 LT |
6389 | |
6390 | deliver = SCTP_CMD_CHUNK_ULP; | |
6391 | ||
6392 | /* Think about partial delivery. */ | |
6393 | if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) { | |
6394 | ||
6395 | /* Even if we don't accept this chunk there is | |
6396 | * memory pressure. | |
6397 | */ | |
6398 | sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL()); | |
6399 | } | |
6400 | ||
d808ad9a | 6401 | /* Spill over rwnd a little bit. Note: While allowed, this spill over |
1da177e4 LT |
6402 | * seems a bit troublesome in that frag_point varies based on |
6403 | * PMTU. In cases, such as loopback, this might be a rather | |
6404 | * large spill over. | |
4d93df0a | 6405 | */ |
362d5204 | 6406 | if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over || |
4d93df0a | 6407 | (datalen > asoc->rwnd + asoc->frag_point))) { |
1da177e4 LT |
6408 | |
6409 | /* If this is the next TSN, consider reneging to make | |
6410 | * room. Note: Playing nice with a confused sender. A | |
6411 | * malicious sender can still eat up all our buffer | |
6412 | * space and in the future we may want to detect and | |
6413 | * do more drastic reneging. | |
6414 | */ | |
7c3ceb4f NH |
6415 | if (sctp_tsnmap_has_gap(map) && |
6416 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
bb33381d | 6417 | pr_debug("%s: reneging for tsn:%u\n", __func__, tsn); |
1da177e4 LT |
6418 | deliver = SCTP_CMD_RENEGE; |
6419 | } else { | |
bb33381d DB |
6420 | pr_debug("%s: discard tsn:%u len:%zu, rwnd:%d\n", |
6421 | __func__, tsn, datalen, asoc->rwnd); | |
6422 | ||
1da177e4 LT |
6423 | return SCTP_IERROR_IGNORE_TSN; |
6424 | } | |
6425 | } | |
6426 | ||
4d93df0a NH |
6427 | /* |
6428 | * Also try to renege to limit our memory usage in the event that | |
6429 | * we are under memory pressure | |
3ab224be | 6430 | * If we can't renege, don't worry about it, the sk_rmem_schedule |
4d93df0a NH |
6431 | * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our |
6432 | * memory usage too much | |
6433 | */ | |
6434 | if (*sk->sk_prot_creator->memory_pressure) { | |
6435 | if (sctp_tsnmap_has_gap(map) && | |
f7010e61 | 6436 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { |
bb33381d DB |
6437 | pr_debug("%s: under pressure, reneging for tsn:%u\n", |
6438 | __func__, tsn); | |
4d93df0a NH |
6439 | deliver = SCTP_CMD_RENEGE; |
6440 | } | |
6441 | } | |
6442 | ||
1da177e4 LT |
6443 | /* |
6444 | * Section 3.3.10.9 No User Data (9) | |
6445 | * | |
6446 | * Cause of error | |
6447 | * --------------- | |
6448 | * No User Data: This error cause is returned to the originator of a | |
6449 | * DATA chunk if a received DATA chunk has no user data. | |
6450 | */ | |
6451 | if (unlikely(0 == datalen)) { | |
6452 | err = sctp_make_abort_no_data(asoc, chunk, tsn); | |
6453 | if (err) { | |
6454 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6455 | SCTP_CHUNK(err)); | |
6456 | } | |
6457 | /* We are going to ABORT, so we might as well stop | |
6458 | * processing the rest of the chunks in the packet. | |
6459 | */ | |
cb3f837b | 6460 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
8de8c873 SS |
6461 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
6462 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 | 6463 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 6464 | SCTP_PERR(SCTP_ERROR_NO_DATA)); |
b01a2407 EB |
6465 | SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS); |
6466 | SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB); | |
1da177e4 LT |
6467 | return SCTP_IERROR_NO_DATA; |
6468 | } | |
6469 | ||
9faa730f SS |
6470 | chunk->data_accepted = 1; |
6471 | ||
1da177e4 LT |
6472 | /* Note: Some chunks may get overcounted (if we drop) or overcounted |
6473 | * if we renege and the chunk arrives again. | |
6474 | */ | |
196d6759 | 6475 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) { |
b01a2407 | 6476 | SCTP_INC_STATS(net, SCTP_MIB_INUNORDERCHUNKS); |
196d6759 MB |
6477 | if (chunk->asoc) |
6478 | chunk->asoc->stats.iuodchunks++; | |
6479 | } else { | |
b01a2407 | 6480 | SCTP_INC_STATS(net, SCTP_MIB_INORDERCHUNKS); |
196d6759 MB |
6481 | if (chunk->asoc) |
6482 | chunk->asoc->stats.iodchunks++; | |
f1751c57 | 6483 | } |
1da177e4 LT |
6484 | |
6485 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
6486 | * | |
6487 | * If an endpoint receive a DATA chunk with an invalid stream | |
6488 | * identifier, it shall acknowledge the reception of the DATA chunk | |
6489 | * following the normal procedure, immediately send an ERROR chunk | |
6490 | * with cause set to "Invalid Stream Identifier" (See Section 3.3.10) | |
6491 | * and discard the DATA chunk. | |
6492 | */ | |
9d4ceaf1 | 6493 | if (ntohs(data_hdr->stream) >= asoc->stream.incnt) { |
3888e9ef VY |
6494 | /* Mark tsn as received even though we drop it */ |
6495 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn)); | |
6496 | ||
1da177e4 LT |
6497 | err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM, |
6498 | &data_hdr->stream, | |
6383cfb3 VY |
6499 | sizeof(data_hdr->stream), |
6500 | sizeof(u16)); | |
1da177e4 LT |
6501 | if (err) |
6502 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6503 | SCTP_CHUNK(err)); | |
6504 | return SCTP_IERROR_BAD_STREAM; | |
6505 | } | |
6506 | ||
f1751c57 VY |
6507 | /* Check to see if the SSN is possible for this TSN. |
6508 | * The biggest gap we can record is 4K wide. Since SSNs wrap | |
6509 | * at an unsigned short, there is no way that an SSN can | |
6510 | * wrap and for a valid TSN. We can simply check if the current | |
6511 | * SSN is smaller then the next expected one. If it is, it wrapped | |
6512 | * and is invalid. | |
6513 | */ | |
9d4ceaf1 | 6514 | if (!asoc->stream.si->validate_data(chunk)) |
f1751c57 | 6515 | return SCTP_IERROR_PROTO_VIOLATION; |
f1751c57 | 6516 | |
1da177e4 LT |
6517 | /* Send the data up to the user. Note: Schedule the |
6518 | * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK | |
6519 | * chunk needs the updated rwnd. | |
6520 | */ | |
6521 | sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk)); | |
6522 | ||
6523 | return SCTP_IERROR_NO_ERROR; | |
6524 | } |