Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* SCTP kernel reference Implementation |
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 | * | |
7 | * This file is part of the SCTP kernel reference Implementation | |
8 | * | |
9 | * These functions work with the state functions in sctp_sm_statefuns.c | |
10 | * to implement the state operations. These functions implement the | |
11 | * steps which require modifying existing data structures. | |
12 | * | |
13 | * The SCTP reference implementation is free software; | |
14 | * you can redistribute it and/or modify it under the terms of | |
15 | * the GNU General Public License as published by | |
16 | * the Free Software Foundation; either version 2, or (at your option) | |
17 | * any later version. | |
18 | * | |
19 | * The SCTP reference implementation is distributed in the hope that it | |
20 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied | |
21 | * ************************ | |
22 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
23 | * See the GNU General Public License for more details. | |
24 | * | |
25 | * You should have received a copy of the GNU General Public License | |
26 | * along with GNU CC; see the file COPYING. If not, write to | |
27 | * the Free Software Foundation, 59 Temple Place - Suite 330, | |
28 | * Boston, MA 02111-1307, USA. | |
29 | * | |
30 | * Please send any bug reports or fixes you make to the | |
31 | * email address(es): | |
32 | * lksctp developers <lksctp-developers@lists.sourceforge.net> | |
33 | * | |
34 | * Or submit a bug report through the following website: | |
35 | * http://www.sf.net/projects/lksctp | |
36 | * | |
37 | * Written or modified by: | |
38 | * La Monte H.P. Yarroll <piggy@acm.org> | |
39 | * Karl Knutson <karl@athena.chicago.il.us> | |
40 | * C. Robin <chris@hundredacre.ac.uk> | |
41 | * Jon Grimm <jgrimm@us.ibm.com> | |
42 | * Xingang Guo <xingang.guo@intel.com> | |
43 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
44 | * Sridhar Samudrala <sri@us.ibm.com> | |
45 | * Daisy Chang <daisyc@us.ibm.com> | |
46 | * Ardelle Fan <ardelle.fan@intel.com> | |
47 | * Kevin Gao <kevin.gao@intel.com> | |
48 | * | |
49 | * Any bugs reported given to us we will try to fix... any fixes shared will | |
50 | * be incorporated into the next SCTP release. | |
51 | */ | |
52 | ||
53 | #include <linux/types.h> | |
54 | #include <linux/kernel.h> | |
55 | #include <linux/ip.h> | |
56 | #include <linux/ipv6.h> | |
57 | #include <linux/net.h> | |
58 | #include <linux/inet.h> | |
59 | #include <asm/scatterlist.h> | |
60 | #include <linux/crypto.h> | |
61 | #include <net/sock.h> | |
62 | ||
63 | #include <linux/skbuff.h> | |
64 | #include <linux/random.h> /* for get_random_bytes */ | |
65 | #include <net/sctp/sctp.h> | |
66 | #include <net/sctp/sm.h> | |
67 | ||
68 | extern kmem_cache_t *sctp_chunk_cachep; | |
69 | ||
70 | SCTP_STATIC | |
71 | struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc, | |
72 | __u8 type, __u8 flags, int paylen); | |
73 | static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep, | |
74 | const struct sctp_association *asoc, | |
75 | const struct sctp_chunk *init_chunk, | |
76 | int *cookie_len, | |
77 | const __u8 *raw_addrs, int addrs_len); | |
78 | static int sctp_process_param(struct sctp_association *asoc, | |
79 | union sctp_params param, | |
80 | const union sctp_addr *peer_addr, | |
81 | int gfp); | |
82 | ||
83 | /* What was the inbound interface for this chunk? */ | |
84 | int sctp_chunk_iif(const struct sctp_chunk *chunk) | |
85 | { | |
86 | struct sctp_af *af; | |
87 | int iif = 0; | |
88 | ||
89 | af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->version)); | |
90 | if (af) | |
91 | iif = af->skb_iif(chunk->skb); | |
92 | ||
93 | return iif; | |
94 | } | |
95 | ||
96 | /* RFC 2960 3.3.2 Initiation (INIT) (1) | |
97 | * | |
98 | * Note 2: The ECN capable field is reserved for future use of | |
99 | * Explicit Congestion Notification. | |
100 | */ | |
101 | static const struct sctp_paramhdr ecap_param = { | |
102 | SCTP_PARAM_ECN_CAPABLE, | |
103 | __constant_htons(sizeof(struct sctp_paramhdr)), | |
104 | }; | |
105 | static const struct sctp_paramhdr prsctp_param = { | |
106 | SCTP_PARAM_FWD_TSN_SUPPORT, | |
107 | __constant_htons(sizeof(struct sctp_paramhdr)), | |
108 | }; | |
109 | ||
110 | /* A helper to initialize to initialize an op error inside a | |
111 | * provided chunk, as most cause codes will be embedded inside an | |
112 | * abort chunk. | |
113 | */ | |
114 | void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code, | |
115 | const void *payload, size_t paylen) | |
116 | { | |
117 | sctp_errhdr_t err; | |
118 | int padlen; | |
119 | __u16 len; | |
120 | ||
121 | /* Cause code constants are now defined in network order. */ | |
122 | err.cause = cause_code; | |
123 | len = sizeof(sctp_errhdr_t) + paylen; | |
124 | padlen = len % 4; | |
125 | err.length = htons(len); | |
126 | len += padlen; | |
127 | sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err); | |
128 | chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload); | |
129 | } | |
130 | ||
131 | /* 3.3.2 Initiation (INIT) (1) | |
132 | * | |
133 | * This chunk is used to initiate a SCTP association between two | |
134 | * endpoints. The format of the INIT chunk is shown below: | |
135 | * | |
136 | * 0 1 2 3 | |
137 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
138 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
139 | * | Type = 1 | Chunk Flags | Chunk Length | | |
140 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
141 | * | Initiate Tag | | |
142 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
143 | * | Advertised Receiver Window Credit (a_rwnd) | | |
144 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
145 | * | Number of Outbound Streams | Number of Inbound Streams | | |
146 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
147 | * | Initial TSN | | |
148 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
149 | * \ \ | |
150 | * / Optional/Variable-Length Parameters / | |
151 | * \ \ | |
152 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
153 | * | |
154 | * | |
155 | * The INIT chunk contains the following parameters. Unless otherwise | |
156 | * noted, each parameter MUST only be included once in the INIT chunk. | |
157 | * | |
158 | * Fixed Parameters Status | |
159 | * ---------------------------------------------- | |
160 | * Initiate Tag Mandatory | |
161 | * Advertised Receiver Window Credit Mandatory | |
162 | * Number of Outbound Streams Mandatory | |
163 | * Number of Inbound Streams Mandatory | |
164 | * Initial TSN Mandatory | |
165 | * | |
166 | * Variable Parameters Status Type Value | |
167 | * ------------------------------------------------------------- | |
168 | * IPv4 Address (Note 1) Optional 5 | |
169 | * IPv6 Address (Note 1) Optional 6 | |
170 | * Cookie Preservative Optional 9 | |
171 | * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000) | |
172 | * Host Name Address (Note 3) Optional 11 | |
173 | * Supported Address Types (Note 4) Optional 12 | |
174 | */ | |
175 | struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, | |
176 | const struct sctp_bind_addr *bp, | |
177 | int gfp, int vparam_len) | |
178 | { | |
179 | sctp_inithdr_t init; | |
180 | union sctp_params addrs; | |
181 | size_t chunksize; | |
182 | struct sctp_chunk *retval = NULL; | |
183 | int num_types, addrs_len = 0; | |
184 | struct sctp_sock *sp; | |
185 | sctp_supported_addrs_param_t sat; | |
186 | __u16 types[2]; | |
187 | sctp_adaption_ind_param_t aiparam; | |
188 | ||
189 | /* RFC 2960 3.3.2 Initiation (INIT) (1) | |
190 | * | |
191 | * Note 1: The INIT chunks can contain multiple addresses that | |
192 | * can be IPv4 and/or IPv6 in any combination. | |
193 | */ | |
194 | retval = NULL; | |
195 | ||
196 | /* Convert the provided bind address list to raw format. */ | |
197 | addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp); | |
198 | ||
199 | init.init_tag = htonl(asoc->c.my_vtag); | |
200 | init.a_rwnd = htonl(asoc->rwnd); | |
201 | init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); | |
202 | init.num_inbound_streams = htons(asoc->c.sinit_max_instreams); | |
203 | init.initial_tsn = htonl(asoc->c.initial_tsn); | |
204 | ||
205 | /* How many address types are needed? */ | |
206 | sp = sctp_sk(asoc->base.sk); | |
207 | num_types = sp->pf->supported_addrs(sp, types); | |
208 | ||
209 | chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types); | |
210 | chunksize += sizeof(ecap_param); | |
211 | if (sctp_prsctp_enable) | |
212 | chunksize += sizeof(prsctp_param); | |
213 | chunksize += sizeof(aiparam); | |
214 | chunksize += vparam_len; | |
215 | ||
216 | /* RFC 2960 3.3.2 Initiation (INIT) (1) | |
217 | * | |
218 | * Note 3: An INIT chunk MUST NOT contain more than one Host | |
219 | * Name address parameter. Moreover, the sender of the INIT | |
220 | * MUST NOT combine any other address types with the Host Name | |
221 | * address in the INIT. The receiver of INIT MUST ignore any | |
222 | * other address types if the Host Name address parameter is | |
223 | * present in the received INIT chunk. | |
224 | * | |
225 | * PLEASE DO NOT FIXME [This version does not support Host Name.] | |
226 | */ | |
227 | ||
228 | retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize); | |
229 | if (!retval) | |
230 | goto nodata; | |
231 | ||
232 | retval->subh.init_hdr = | |
233 | sctp_addto_chunk(retval, sizeof(init), &init); | |
234 | retval->param_hdr.v = | |
235 | sctp_addto_chunk(retval, addrs_len, addrs.v); | |
236 | ||
237 | /* RFC 2960 3.3.2 Initiation (INIT) (1) | |
238 | * | |
239 | * Note 4: This parameter, when present, specifies all the | |
240 | * address types the sending endpoint can support. The absence | |
241 | * of this parameter indicates that the sending endpoint can | |
242 | * support any address type. | |
243 | */ | |
244 | sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES; | |
245 | sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types)); | |
246 | sctp_addto_chunk(retval, sizeof(sat), &sat); | |
247 | sctp_addto_chunk(retval, num_types * sizeof(__u16), &types); | |
248 | ||
249 | sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); | |
250 | if (sctp_prsctp_enable) | |
251 | sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); | |
252 | aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND; | |
253 | aiparam.param_hdr.length = htons(sizeof(aiparam)); | |
254 | aiparam.adaption_ind = htonl(sp->adaption_ind); | |
255 | sctp_addto_chunk(retval, sizeof(aiparam), &aiparam); | |
256 | nodata: | |
257 | if (addrs.v) | |
258 | kfree(addrs.v); | |
259 | return retval; | |
260 | } | |
261 | ||
262 | struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, | |
263 | const struct sctp_chunk *chunk, | |
264 | int gfp, int unkparam_len) | |
265 | { | |
266 | sctp_inithdr_t initack; | |
267 | struct sctp_chunk *retval; | |
268 | union sctp_params addrs; | |
269 | int addrs_len; | |
270 | sctp_cookie_param_t *cookie; | |
271 | int cookie_len; | |
272 | size_t chunksize; | |
273 | sctp_adaption_ind_param_t aiparam; | |
274 | ||
275 | retval = NULL; | |
276 | ||
277 | /* Note: there may be no addresses to embed. */ | |
278 | addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp); | |
279 | ||
280 | initack.init_tag = htonl(asoc->c.my_vtag); | |
281 | initack.a_rwnd = htonl(asoc->rwnd); | |
282 | initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); | |
283 | initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams); | |
284 | initack.initial_tsn = htonl(asoc->c.initial_tsn); | |
285 | ||
286 | /* FIXME: We really ought to build the cookie right | |
287 | * into the packet instead of allocating more fresh memory. | |
288 | */ | |
289 | cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len, | |
290 | addrs.v, addrs_len); | |
291 | if (!cookie) | |
292 | goto nomem_cookie; | |
293 | ||
294 | /* Calculate the total size of allocation, include the reserved | |
295 | * space for reporting unknown parameters if it is specified. | |
296 | */ | |
297 | chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len; | |
298 | ||
299 | /* Tell peer that we'll do ECN only if peer advertised such cap. */ | |
300 | if (asoc->peer.ecn_capable) | |
301 | chunksize += sizeof(ecap_param); | |
302 | ||
303 | /* Tell peer that we'll do PR-SCTP only if peer advertised. */ | |
304 | if (asoc->peer.prsctp_capable) | |
305 | chunksize += sizeof(prsctp_param); | |
306 | ||
307 | chunksize += sizeof(aiparam); | |
308 | ||
309 | /* Now allocate and fill out the chunk. */ | |
310 | retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize); | |
311 | if (!retval) | |
312 | goto nomem_chunk; | |
313 | ||
314 | /* Per the advice in RFC 2960 6.4, send this reply to | |
315 | * the source of the INIT packet. | |
316 | */ | |
317 | retval->transport = chunk->transport; | |
318 | retval->subh.init_hdr = | |
319 | sctp_addto_chunk(retval, sizeof(initack), &initack); | |
320 | retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v); | |
321 | sctp_addto_chunk(retval, cookie_len, cookie); | |
322 | if (asoc->peer.ecn_capable) | |
323 | sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); | |
324 | if (asoc->peer.prsctp_capable) | |
325 | sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); | |
326 | ||
327 | aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND; | |
328 | aiparam.param_hdr.length = htons(sizeof(aiparam)); | |
329 | aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind); | |
330 | sctp_addto_chunk(retval, sizeof(aiparam), &aiparam); | |
331 | ||
332 | /* We need to remove the const qualifier at this point. */ | |
333 | retval->asoc = (struct sctp_association *) asoc; | |
334 | ||
335 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
336 | * | |
337 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
338 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
339 | * address from which it received the DATA or control chunk | |
340 | * to which it is replying. | |
341 | * | |
342 | * [INIT ACK back to where the INIT came from.] | |
343 | */ | |
344 | if (chunk) | |
345 | retval->transport = chunk->transport; | |
346 | ||
347 | nomem_chunk: | |
348 | kfree(cookie); | |
349 | nomem_cookie: | |
350 | if (addrs.v) | |
351 | kfree(addrs.v); | |
352 | return retval; | |
353 | } | |
354 | ||
355 | /* 3.3.11 Cookie Echo (COOKIE ECHO) (10): | |
356 | * | |
357 | * This chunk is used only during the initialization of an association. | |
358 | * It is sent by the initiator of an association to its peer to complete | |
359 | * the initialization process. This chunk MUST precede any DATA chunk | |
360 | * sent within the association, but MAY be bundled with one or more DATA | |
361 | * chunks in the same packet. | |
362 | * | |
363 | * 0 1 2 3 | |
364 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
365 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
366 | * | Type = 10 |Chunk Flags | Length | | |
367 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
368 | * / Cookie / | |
369 | * \ \ | |
370 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
371 | * | |
372 | * Chunk Flags: 8 bit | |
373 | * | |
374 | * Set to zero on transmit and ignored on receipt. | |
375 | * | |
376 | * Length: 16 bits (unsigned integer) | |
377 | * | |
378 | * Set to the size of the chunk in bytes, including the 4 bytes of | |
379 | * the chunk header and the size of the Cookie. | |
380 | * | |
381 | * Cookie: variable size | |
382 | * | |
383 | * This field must contain the exact cookie received in the | |
384 | * State Cookie parameter from the previous INIT ACK. | |
385 | * | |
386 | * An implementation SHOULD make the cookie as small as possible | |
387 | * to insure interoperability. | |
388 | */ | |
389 | struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc, | |
390 | const struct sctp_chunk *chunk) | |
391 | { | |
392 | struct sctp_chunk *retval; | |
393 | void *cookie; | |
394 | int cookie_len; | |
395 | ||
396 | cookie = asoc->peer.cookie; | |
397 | cookie_len = asoc->peer.cookie_len; | |
398 | ||
399 | /* Build a cookie echo chunk. */ | |
400 | retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len); | |
401 | if (!retval) | |
402 | goto nodata; | |
403 | retval->subh.cookie_hdr = | |
404 | sctp_addto_chunk(retval, cookie_len, cookie); | |
405 | ||
406 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
407 | * | |
408 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
409 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
410 | * address from which it * received the DATA or control chunk | |
411 | * to which it is replying. | |
412 | * | |
413 | * [COOKIE ECHO back to where the INIT ACK came from.] | |
414 | */ | |
415 | if (chunk) | |
416 | retval->transport = chunk->transport; | |
417 | ||
418 | nodata: | |
419 | return retval; | |
420 | } | |
421 | ||
422 | /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11): | |
423 | * | |
424 | * This chunk is used only during the initialization of an | |
425 | * association. It is used to acknowledge the receipt of a COOKIE | |
426 | * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent | |
427 | * within the association, but MAY be bundled with one or more DATA | |
428 | * chunks or SACK chunk in the same SCTP packet. | |
429 | * | |
430 | * 0 1 2 3 | |
431 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
432 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
433 | * | Type = 11 |Chunk Flags | Length = 4 | | |
434 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
435 | * | |
436 | * Chunk Flags: 8 bits | |
437 | * | |
438 | * Set to zero on transmit and ignored on receipt. | |
439 | */ | |
440 | struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc, | |
441 | const struct sctp_chunk *chunk) | |
442 | { | |
443 | struct sctp_chunk *retval; | |
444 | ||
445 | retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0); | |
446 | ||
447 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
448 | * | |
449 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
450 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
451 | * address from which it * received the DATA or control chunk | |
452 | * to which it is replying. | |
453 | * | |
454 | * [COOKIE ACK back to where the COOKIE ECHO came from.] | |
455 | */ | |
456 | if (retval && chunk) | |
457 | retval->transport = chunk->transport; | |
458 | ||
459 | return retval; | |
460 | } | |
461 | ||
462 | /* | |
463 | * Appendix A: Explicit Congestion Notification: | |
464 | * CWR: | |
465 | * | |
466 | * RFC 2481 details a specific bit for a sender to send in the header of | |
467 | * its next outbound TCP segment to indicate to its peer that it has | |
468 | * reduced its congestion window. This is termed the CWR bit. For | |
469 | * SCTP the same indication is made by including the CWR chunk. | |
470 | * This chunk contains one data element, i.e. the TSN number that | |
471 | * was sent in the ECNE chunk. This element represents the lowest | |
472 | * TSN number in the datagram that was originally marked with the | |
473 | * CE bit. | |
474 | * | |
475 | * 0 1 2 3 | |
476 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
477 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
478 | * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 | | |
479 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
480 | * | Lowest TSN Number | | |
481 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
482 | * | |
483 | * Note: The CWR is considered a Control chunk. | |
484 | */ | |
485 | struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc, | |
486 | const __u32 lowest_tsn, | |
487 | const struct sctp_chunk *chunk) | |
488 | { | |
489 | struct sctp_chunk *retval; | |
490 | sctp_cwrhdr_t cwr; | |
491 | ||
492 | cwr.lowest_tsn = htonl(lowest_tsn); | |
493 | retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0, | |
494 | sizeof(sctp_cwrhdr_t)); | |
495 | ||
496 | if (!retval) | |
497 | goto nodata; | |
498 | ||
499 | retval->subh.ecn_cwr_hdr = | |
500 | sctp_addto_chunk(retval, sizeof(cwr), &cwr); | |
501 | ||
502 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
503 | * | |
504 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
505 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
506 | * address from which it * received the DATA or control chunk | |
507 | * to which it is replying. | |
508 | * | |
509 | * [Report a reduced congestion window back to where the ECNE | |
510 | * came from.] | |
511 | */ | |
512 | if (chunk) | |
513 | retval->transport = chunk->transport; | |
514 | ||
515 | nodata: | |
516 | return retval; | |
517 | } | |
518 | ||
519 | /* Make an ECNE chunk. This is a congestion experienced report. */ | |
520 | struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc, | |
521 | const __u32 lowest_tsn) | |
522 | { | |
523 | struct sctp_chunk *retval; | |
524 | sctp_ecnehdr_t ecne; | |
525 | ||
526 | ecne.lowest_tsn = htonl(lowest_tsn); | |
527 | retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0, | |
528 | sizeof(sctp_ecnehdr_t)); | |
529 | if (!retval) | |
530 | goto nodata; | |
531 | retval->subh.ecne_hdr = | |
532 | sctp_addto_chunk(retval, sizeof(ecne), &ecne); | |
533 | ||
534 | nodata: | |
535 | return retval; | |
536 | } | |
537 | ||
538 | /* Make a DATA chunk for the given association from the provided | |
539 | * parameters. However, do not populate the data payload. | |
540 | */ | |
541 | struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc, | |
542 | const struct sctp_sndrcvinfo *sinfo, | |
543 | int data_len, __u8 flags, __u16 ssn) | |
544 | { | |
545 | struct sctp_chunk *retval; | |
546 | struct sctp_datahdr dp; | |
547 | int chunk_len; | |
548 | ||
549 | /* We assign the TSN as LATE as possible, not here when | |
550 | * creating the chunk. | |
551 | */ | |
552 | dp.tsn = 0; | |
553 | dp.stream = htons(sinfo->sinfo_stream); | |
554 | dp.ppid = sinfo->sinfo_ppid; | |
555 | ||
556 | /* Set the flags for an unordered send. */ | |
557 | if (sinfo->sinfo_flags & MSG_UNORDERED) { | |
558 | flags |= SCTP_DATA_UNORDERED; | |
559 | dp.ssn = 0; | |
560 | } else | |
561 | dp.ssn = htons(ssn); | |
562 | ||
563 | chunk_len = sizeof(dp) + data_len; | |
564 | retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len); | |
565 | if (!retval) | |
566 | goto nodata; | |
567 | ||
568 | retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp); | |
569 | memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo)); | |
570 | ||
571 | nodata: | |
572 | return retval; | |
573 | } | |
574 | ||
575 | /* Create a selective ackowledgement (SACK) for the given | |
576 | * association. This reports on which TSN's we've seen to date, | |
577 | * including duplicates and gaps. | |
578 | */ | |
579 | struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc) | |
580 | { | |
581 | struct sctp_chunk *retval; | |
582 | struct sctp_sackhdr sack; | |
583 | int len; | |
584 | __u32 ctsn; | |
585 | __u16 num_gabs, num_dup_tsns; | |
586 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; | |
587 | ||
588 | ctsn = sctp_tsnmap_get_ctsn(map); | |
589 | SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn); | |
590 | ||
591 | /* How much room is needed in the chunk? */ | |
592 | num_gabs = sctp_tsnmap_num_gabs(map); | |
593 | num_dup_tsns = sctp_tsnmap_num_dups(map); | |
594 | ||
595 | /* Initialize the SACK header. */ | |
596 | sack.cum_tsn_ack = htonl(ctsn); | |
597 | sack.a_rwnd = htonl(asoc->a_rwnd); | |
598 | sack.num_gap_ack_blocks = htons(num_gabs); | |
599 | sack.num_dup_tsns = htons(num_dup_tsns); | |
600 | ||
601 | len = sizeof(sack) | |
602 | + sizeof(struct sctp_gap_ack_block) * num_gabs | |
603 | + sizeof(__u32) * num_dup_tsns; | |
604 | ||
605 | /* Create the chunk. */ | |
606 | retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len); | |
607 | if (!retval) | |
608 | goto nodata; | |
609 | ||
610 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
611 | * | |
612 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
613 | * HEARTBEAT ACK, etc.) to the same destination transport | |
614 | * address from which it received the DATA or control chunk to | |
615 | * which it is replying. This rule should also be followed if | |
616 | * the endpoint is bundling DATA chunks together with the | |
617 | * reply chunk. | |
618 | * | |
619 | * However, when acknowledging multiple DATA chunks received | |
620 | * in packets from different source addresses in a single | |
621 | * SACK, the SACK chunk may be transmitted to one of the | |
622 | * destination transport addresses from which the DATA or | |
623 | * control chunks being acknowledged were received. | |
624 | * | |
625 | * [BUG: We do not implement the following paragraph. | |
626 | * Perhaps we should remember the last transport we used for a | |
627 | * SACK and avoid that (if possible) if we have seen any | |
628 | * duplicates. --piggy] | |
629 | * | |
630 | * When a receiver of a duplicate DATA chunk sends a SACK to a | |
631 | * multi- homed endpoint it MAY be beneficial to vary the | |
632 | * destination address and not use the source address of the | |
633 | * DATA chunk. The reason being that receiving a duplicate | |
634 | * from a multi-homed endpoint might indicate that the return | |
635 | * path (as specified in the source address of the DATA chunk) | |
636 | * for the SACK is broken. | |
637 | * | |
638 | * [Send to the address from which we last received a DATA chunk.] | |
639 | */ | |
640 | retval->transport = asoc->peer.last_data_from; | |
641 | ||
642 | retval->subh.sack_hdr = | |
643 | sctp_addto_chunk(retval, sizeof(sack), &sack); | |
644 | ||
645 | /* Add the gap ack block information. */ | |
646 | if (num_gabs) | |
647 | sctp_addto_chunk(retval, sizeof(__u32) * num_gabs, | |
648 | sctp_tsnmap_get_gabs(map)); | |
649 | ||
650 | /* Add the duplicate TSN information. */ | |
651 | if (num_dup_tsns) | |
652 | sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns, | |
653 | sctp_tsnmap_get_dups(map)); | |
654 | ||
655 | nodata: | |
656 | return retval; | |
657 | } | |
658 | ||
659 | /* Make a SHUTDOWN chunk. */ | |
660 | struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc, | |
661 | const struct sctp_chunk *chunk) | |
662 | { | |
663 | struct sctp_chunk *retval; | |
664 | sctp_shutdownhdr_t shut; | |
665 | __u32 ctsn; | |
666 | ||
667 | ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); | |
668 | shut.cum_tsn_ack = htonl(ctsn); | |
669 | ||
670 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0, | |
671 | sizeof(sctp_shutdownhdr_t)); | |
672 | if (!retval) | |
673 | goto nodata; | |
674 | ||
675 | retval->subh.shutdown_hdr = | |
676 | sctp_addto_chunk(retval, sizeof(shut), &shut); | |
677 | ||
678 | if (chunk) | |
679 | retval->transport = chunk->transport; | |
680 | nodata: | |
681 | return retval; | |
682 | } | |
683 | ||
684 | struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc, | |
685 | const struct sctp_chunk *chunk) | |
686 | { | |
687 | struct sctp_chunk *retval; | |
688 | ||
689 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0); | |
690 | ||
691 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
692 | * | |
693 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
694 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
695 | * address from which it * received the DATA or control chunk | |
696 | * to which it is replying. | |
697 | * | |
698 | * [ACK back to where the SHUTDOWN came from.] | |
699 | */ | |
700 | if (retval && chunk) | |
701 | retval->transport = chunk->transport; | |
702 | ||
703 | return retval; | |
704 | } | |
705 | ||
706 | struct sctp_chunk *sctp_make_shutdown_complete( | |
707 | const struct sctp_association *asoc, | |
708 | const struct sctp_chunk *chunk) | |
709 | { | |
710 | struct sctp_chunk *retval; | |
711 | __u8 flags = 0; | |
712 | ||
713 | /* Maybe set the T-bit if we have no association. */ | |
714 | flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T; | |
715 | ||
716 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0); | |
717 | ||
718 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
719 | * | |
720 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
721 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
722 | * address from which it * received the DATA or control chunk | |
723 | * to which it is replying. | |
724 | * | |
725 | * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK | |
726 | * came from.] | |
727 | */ | |
728 | if (retval && chunk) | |
729 | retval->transport = chunk->transport; | |
730 | ||
731 | return retval; | |
732 | } | |
733 | ||
734 | /* Create an ABORT. Note that we set the T bit if we have no | |
735 | * association. | |
736 | */ | |
737 | struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc, | |
738 | const struct sctp_chunk *chunk, | |
739 | const size_t hint) | |
740 | { | |
741 | struct sctp_chunk *retval; | |
742 | __u8 flags = 0; | |
743 | ||
744 | /* Maybe set the T-bit if we have no association. */ | |
745 | flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T; | |
746 | ||
747 | retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint); | |
748 | ||
749 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
750 | * | |
751 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
752 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
753 | * address from which it * received the DATA or control chunk | |
754 | * to which it is replying. | |
755 | * | |
756 | * [ABORT back to where the offender came from.] | |
757 | */ | |
758 | if (retval && chunk) | |
759 | retval->transport = chunk->transport; | |
760 | ||
761 | return retval; | |
762 | } | |
763 | ||
764 | /* Helper to create ABORT with a NO_USER_DATA error. */ | |
765 | struct sctp_chunk *sctp_make_abort_no_data( | |
766 | const struct sctp_association *asoc, | |
767 | const struct sctp_chunk *chunk, __u32 tsn) | |
768 | { | |
769 | struct sctp_chunk *retval; | |
770 | __u32 payload; | |
771 | ||
772 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) | |
773 | + sizeof(tsn)); | |
774 | ||
775 | if (!retval) | |
776 | goto no_mem; | |
777 | ||
778 | /* Put the tsn back into network byte order. */ | |
779 | payload = htonl(tsn); | |
780 | sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload, | |
781 | sizeof(payload)); | |
782 | ||
783 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
784 | * | |
785 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
786 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
787 | * address from which it * received the DATA or control chunk | |
788 | * to which it is replying. | |
789 | * | |
790 | * [ABORT back to where the offender came from.] | |
791 | */ | |
792 | if (chunk) | |
793 | retval->transport = chunk->transport; | |
794 | ||
795 | no_mem: | |
796 | return retval; | |
797 | } | |
798 | ||
799 | /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */ | |
800 | struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc, | |
801 | const struct sctp_chunk *chunk, | |
802 | const struct msghdr *msg) | |
803 | { | |
804 | struct sctp_chunk *retval; | |
805 | void *payload = NULL, *payoff; | |
806 | size_t paylen = 0; | |
807 | struct iovec *iov = NULL; | |
808 | int iovlen = 0; | |
809 | ||
810 | if (msg) { | |
811 | iov = msg->msg_iov; | |
812 | iovlen = msg->msg_iovlen; | |
813 | paylen = get_user_iov_size(iov, iovlen); | |
814 | } | |
815 | ||
816 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen); | |
817 | if (!retval) | |
818 | goto err_chunk; | |
819 | ||
820 | if (paylen) { | |
821 | /* Put the msg_iov together into payload. */ | |
822 | payload = kmalloc(paylen, GFP_ATOMIC); | |
823 | if (!payload) | |
824 | goto err_payload; | |
825 | payoff = payload; | |
826 | ||
827 | for (; iovlen > 0; --iovlen) { | |
828 | if (copy_from_user(payoff, iov->iov_base,iov->iov_len)) | |
829 | goto err_copy; | |
830 | payoff += iov->iov_len; | |
831 | iov++; | |
832 | } | |
833 | } | |
834 | ||
835 | sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen); | |
836 | ||
837 | if (paylen) | |
838 | kfree(payload); | |
839 | ||
840 | return retval; | |
841 | ||
842 | err_copy: | |
843 | kfree(payload); | |
844 | err_payload: | |
845 | sctp_chunk_free(retval); | |
846 | retval = NULL; | |
847 | err_chunk: | |
848 | return retval; | |
849 | } | |
850 | ||
851 | /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */ | |
852 | struct sctp_chunk *sctp_make_abort_violation( | |
853 | const struct sctp_association *asoc, | |
854 | const struct sctp_chunk *chunk, | |
855 | const __u8 *payload, | |
856 | const size_t paylen) | |
857 | { | |
858 | struct sctp_chunk *retval; | |
859 | struct sctp_paramhdr phdr; | |
860 | ||
861 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen | |
862 | + sizeof(sctp_chunkhdr_t)); | |
863 | if (!retval) | |
864 | goto end; | |
865 | ||
866 | sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen); | |
867 | ||
868 | phdr.type = htons(chunk->chunk_hdr->type); | |
869 | phdr.length = chunk->chunk_hdr->length; | |
870 | sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr); | |
871 | ||
872 | end: | |
873 | return retval; | |
874 | } | |
875 | ||
876 | /* Make a HEARTBEAT chunk. */ | |
877 | struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc, | |
878 | const struct sctp_transport *transport, | |
879 | const void *payload, const size_t paylen) | |
880 | { | |
881 | struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT, | |
882 | 0, paylen); | |
883 | ||
884 | if (!retval) | |
885 | goto nodata; | |
886 | ||
887 | /* Cast away the 'const', as this is just telling the chunk | |
888 | * what transport it belongs to. | |
889 | */ | |
890 | retval->transport = (struct sctp_transport *) transport; | |
891 | retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload); | |
892 | ||
893 | nodata: | |
894 | return retval; | |
895 | } | |
896 | ||
897 | struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc, | |
898 | const struct sctp_chunk *chunk, | |
899 | const void *payload, const size_t paylen) | |
900 | { | |
901 | struct sctp_chunk *retval; | |
902 | ||
903 | retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen); | |
904 | if (!retval) | |
905 | goto nodata; | |
906 | ||
907 | retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload); | |
908 | ||
909 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
910 | * | |
911 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
912 | * HEARTBEAT ACK, * etc.) to the same destination transport | |
913 | * address from which it * received the DATA or control chunk | |
914 | * to which it is replying. | |
915 | * | |
916 | * [HBACK back to where the HEARTBEAT came from.] | |
917 | */ | |
918 | if (chunk) | |
919 | retval->transport = chunk->transport; | |
920 | ||
921 | nodata: | |
922 | return retval; | |
923 | } | |
924 | ||
925 | /* Create an Operation Error chunk with the specified space reserved. | |
926 | * This routine can be used for containing multiple causes in the chunk. | |
927 | */ | |
928 | static struct sctp_chunk *sctp_make_op_error_space( | |
929 | const struct sctp_association *asoc, | |
930 | const struct sctp_chunk *chunk, | |
931 | size_t size) | |
932 | { | |
933 | struct sctp_chunk *retval; | |
934 | ||
935 | retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0, | |
936 | sizeof(sctp_errhdr_t) + size); | |
937 | if (!retval) | |
938 | goto nodata; | |
939 | ||
940 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints | |
941 | * | |
942 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, | |
943 | * HEARTBEAT ACK, etc.) to the same destination transport | |
944 | * address from which it received the DATA or control chunk | |
945 | * to which it is replying. | |
946 | * | |
947 | */ | |
948 | if (chunk) | |
949 | retval->transport = chunk->transport; | |
950 | ||
951 | nodata: | |
952 | return retval; | |
953 | } | |
954 | ||
955 | /* Create an Operation Error chunk. */ | |
956 | struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc, | |
957 | const struct sctp_chunk *chunk, | |
958 | __u16 cause_code, const void *payload, | |
959 | size_t paylen) | |
960 | { | |
961 | struct sctp_chunk *retval; | |
962 | ||
963 | retval = sctp_make_op_error_space(asoc, chunk, paylen); | |
964 | if (!retval) | |
965 | goto nodata; | |
966 | ||
967 | sctp_init_cause(retval, cause_code, payload, paylen); | |
968 | ||
969 | nodata: | |
970 | return retval; | |
971 | } | |
972 | ||
973 | /******************************************************************** | |
974 | * 2nd Level Abstractions | |
975 | ********************************************************************/ | |
976 | ||
977 | /* Turn an skb into a chunk. | |
978 | * FIXME: Eventually move the structure directly inside the skb->cb[]. | |
979 | */ | |
980 | struct sctp_chunk *sctp_chunkify(struct sk_buff *skb, | |
981 | const struct sctp_association *asoc, | |
982 | struct sock *sk) | |
983 | { | |
984 | struct sctp_chunk *retval; | |
985 | ||
986 | retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC); | |
987 | ||
988 | if (!retval) | |
989 | goto nodata; | |
990 | memset(retval, 0, sizeof(struct sctp_chunk)); | |
991 | ||
992 | if (!sk) { | |
993 | SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb); | |
994 | } | |
995 | ||
996 | retval->skb = skb; | |
997 | retval->asoc = (struct sctp_association *)asoc; | |
998 | retval->resent = 0; | |
999 | retval->has_tsn = 0; | |
1000 | retval->has_ssn = 0; | |
1001 | retval->rtt_in_progress = 0; | |
1002 | retval->sent_at = 0; | |
1003 | retval->singleton = 1; | |
1004 | retval->end_of_packet = 0; | |
1005 | retval->ecn_ce_done = 0; | |
1006 | retval->pdiscard = 0; | |
1007 | ||
1008 | /* sctpimpguide-05.txt Section 2.8.2 | |
1009 | * M1) Each time a new DATA chunk is transmitted | |
1010 | * set the 'TSN.Missing.Report' count for that TSN to 0. The | |
1011 | * 'TSN.Missing.Report' count will be used to determine missing chunks | |
1012 | * and when to fast retransmit. | |
1013 | */ | |
1014 | retval->tsn_missing_report = 0; | |
1015 | retval->tsn_gap_acked = 0; | |
1016 | retval->fast_retransmit = 0; | |
1017 | ||
1018 | /* If this is a fragmented message, track all fragments | |
1019 | * of the message (for SEND_FAILED). | |
1020 | */ | |
1021 | retval->msg = NULL; | |
1022 | ||
1023 | /* Polish the bead hole. */ | |
1024 | INIT_LIST_HEAD(&retval->transmitted_list); | |
1025 | INIT_LIST_HEAD(&retval->frag_list); | |
1026 | SCTP_DBG_OBJCNT_INC(chunk); | |
1027 | atomic_set(&retval->refcnt, 1); | |
1028 | ||
1029 | nodata: | |
1030 | return retval; | |
1031 | } | |
1032 | ||
1033 | /* Set chunk->source and dest based on the IP header in chunk->skb. */ | |
1034 | void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src, | |
1035 | union sctp_addr *dest) | |
1036 | { | |
1037 | memcpy(&chunk->source, src, sizeof(union sctp_addr)); | |
1038 | memcpy(&chunk->dest, dest, sizeof(union sctp_addr)); | |
1039 | } | |
1040 | ||
1041 | /* Extract the source address from a chunk. */ | |
1042 | const union sctp_addr *sctp_source(const struct sctp_chunk *chunk) | |
1043 | { | |
1044 | /* If we have a known transport, use that. */ | |
1045 | if (chunk->transport) { | |
1046 | return &chunk->transport->ipaddr; | |
1047 | } else { | |
1048 | /* Otherwise, extract it from the IP header. */ | |
1049 | return &chunk->source; | |
1050 | } | |
1051 | } | |
1052 | ||
1053 | /* Create a new chunk, setting the type and flags headers from the | |
1054 | * arguments, reserving enough space for a 'paylen' byte payload. | |
1055 | */ | |
1056 | SCTP_STATIC | |
1057 | struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc, | |
1058 | __u8 type, __u8 flags, int paylen) | |
1059 | { | |
1060 | struct sctp_chunk *retval; | |
1061 | sctp_chunkhdr_t *chunk_hdr; | |
1062 | struct sk_buff *skb; | |
1063 | struct sock *sk; | |
1064 | ||
1065 | /* No need to allocate LL here, as this is only a chunk. */ | |
1066 | skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen), | |
1067 | GFP_ATOMIC); | |
1068 | if (!skb) | |
1069 | goto nodata; | |
1070 | ||
1071 | /* Make room for the chunk header. */ | |
1072 | chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t)); | |
1073 | chunk_hdr->type = type; | |
1074 | chunk_hdr->flags = flags; | |
1075 | chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t)); | |
1076 | ||
1077 | sk = asoc ? asoc->base.sk : NULL; | |
1078 | retval = sctp_chunkify(skb, asoc, sk); | |
1079 | if (!retval) { | |
1080 | kfree_skb(skb); | |
1081 | goto nodata; | |
1082 | } | |
1083 | ||
1084 | retval->chunk_hdr = chunk_hdr; | |
1085 | retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr); | |
1086 | ||
1087 | /* Set the skb to the belonging sock for accounting. */ | |
1088 | skb->sk = sk; | |
1089 | ||
1090 | return retval; | |
1091 | nodata: | |
1092 | return NULL; | |
1093 | } | |
1094 | ||
1095 | ||
1096 | /* Release the memory occupied by a chunk. */ | |
1097 | static void sctp_chunk_destroy(struct sctp_chunk *chunk) | |
1098 | { | |
1099 | /* Free the chunk skb data and the SCTP_chunk stub itself. */ | |
1100 | dev_kfree_skb(chunk->skb); | |
1101 | ||
1102 | SCTP_DBG_OBJCNT_DEC(chunk); | |
1103 | kmem_cache_free(sctp_chunk_cachep, chunk); | |
1104 | } | |
1105 | ||
1106 | /* Possibly, free the chunk. */ | |
1107 | void sctp_chunk_free(struct sctp_chunk *chunk) | |
1108 | { | |
1109 | /* Make sure that we are not on any list. */ | |
1110 | skb_unlink((struct sk_buff *) chunk); | |
1111 | list_del_init(&chunk->transmitted_list); | |
1112 | ||
1113 | /* Release our reference on the message tracker. */ | |
1114 | if (chunk->msg) | |
1115 | sctp_datamsg_put(chunk->msg); | |
1116 | ||
1117 | sctp_chunk_put(chunk); | |
1118 | } | |
1119 | ||
1120 | /* Grab a reference to the chunk. */ | |
1121 | void sctp_chunk_hold(struct sctp_chunk *ch) | |
1122 | { | |
1123 | atomic_inc(&ch->refcnt); | |
1124 | } | |
1125 | ||
1126 | /* Release a reference to the chunk. */ | |
1127 | void sctp_chunk_put(struct sctp_chunk *ch) | |
1128 | { | |
1129 | if (atomic_dec_and_test(&ch->refcnt)) | |
1130 | sctp_chunk_destroy(ch); | |
1131 | } | |
1132 | ||
1133 | /* Append bytes to the end of a chunk. Will panic if chunk is not big | |
1134 | * enough. | |
1135 | */ | |
1136 | void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data) | |
1137 | { | |
1138 | void *target; | |
1139 | void *padding; | |
1140 | int chunklen = ntohs(chunk->chunk_hdr->length); | |
1141 | int padlen = chunklen % 4; | |
1142 | ||
1143 | padding = skb_put(chunk->skb, padlen); | |
1144 | target = skb_put(chunk->skb, len); | |
1145 | ||
1146 | memset(padding, 0, padlen); | |
1147 | memcpy(target, data, len); | |
1148 | ||
1149 | /* Adjust the chunk length field. */ | |
1150 | chunk->chunk_hdr->length = htons(chunklen + padlen + len); | |
1151 | chunk->chunk_end = chunk->skb->tail; | |
1152 | ||
1153 | return target; | |
1154 | } | |
1155 | ||
1156 | /* Append bytes from user space to the end of a chunk. Will panic if | |
1157 | * chunk is not big enough. | |
1158 | * Returns a kernel err value. | |
1159 | */ | |
1160 | int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len, | |
1161 | struct iovec *data) | |
1162 | { | |
1163 | __u8 *target; | |
1164 | int err = 0; | |
1165 | ||
1166 | /* Make room in chunk for data. */ | |
1167 | target = skb_put(chunk->skb, len); | |
1168 | ||
1169 | /* Copy data (whole iovec) into chunk */ | |
1170 | if ((err = memcpy_fromiovecend(target, data, off, len))) | |
1171 | goto out; | |
1172 | ||
1173 | /* Adjust the chunk length field. */ | |
1174 | chunk->chunk_hdr->length = | |
1175 | htons(ntohs(chunk->chunk_hdr->length) + len); | |
1176 | chunk->chunk_end = chunk->skb->tail; | |
1177 | ||
1178 | out: | |
1179 | return err; | |
1180 | } | |
1181 | ||
1182 | /* Helper function to assign a TSN if needed. This assumes that both | |
1183 | * the data_hdr and association have already been assigned. | |
1184 | */ | |
1185 | void sctp_chunk_assign_ssn(struct sctp_chunk *chunk) | |
1186 | { | |
1187 | __u16 ssn; | |
1188 | __u16 sid; | |
1189 | ||
1190 | if (chunk->has_ssn) | |
1191 | return; | |
1192 | ||
1193 | /* This is the last possible instant to assign a SSN. */ | |
1194 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) { | |
1195 | ssn = 0; | |
1196 | } else { | |
1197 | sid = htons(chunk->subh.data_hdr->stream); | |
1198 | if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG) | |
1199 | ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid); | |
1200 | else | |
1201 | ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid); | |
1202 | ssn = htons(ssn); | |
1203 | } | |
1204 | ||
1205 | chunk->subh.data_hdr->ssn = ssn; | |
1206 | chunk->has_ssn = 1; | |
1207 | } | |
1208 | ||
1209 | /* Helper function to assign a TSN if needed. This assumes that both | |
1210 | * the data_hdr and association have already been assigned. | |
1211 | */ | |
1212 | void sctp_chunk_assign_tsn(struct sctp_chunk *chunk) | |
1213 | { | |
1214 | if (!chunk->has_tsn) { | |
1215 | /* This is the last possible instant to | |
1216 | * assign a TSN. | |
1217 | */ | |
1218 | chunk->subh.data_hdr->tsn = | |
1219 | htonl(sctp_association_get_next_tsn(chunk->asoc)); | |
1220 | chunk->has_tsn = 1; | |
1221 | } | |
1222 | } | |
1223 | ||
1224 | /* Create a CLOSED association to use with an incoming packet. */ | |
1225 | struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep, | |
1226 | struct sctp_chunk *chunk, int gfp) | |
1227 | { | |
1228 | struct sctp_association *asoc; | |
1229 | struct sk_buff *skb; | |
1230 | sctp_scope_t scope; | |
1231 | struct sctp_af *af; | |
1232 | ||
1233 | /* Create the bare association. */ | |
1234 | scope = sctp_scope(sctp_source(chunk)); | |
1235 | asoc = sctp_association_new(ep, ep->base.sk, scope, gfp); | |
1236 | if (!asoc) | |
1237 | goto nodata; | |
1238 | asoc->temp = 1; | |
1239 | skb = chunk->skb; | |
1240 | /* Create an entry for the source address of the packet. */ | |
1241 | af = sctp_get_af_specific(ipver2af(skb->nh.iph->version)); | |
1242 | if (unlikely(!af)) | |
1243 | goto fail; | |
1244 | af->from_skb(&asoc->c.peer_addr, skb, 1); | |
1245 | nodata: | |
1246 | return asoc; | |
1247 | ||
1248 | fail: | |
1249 | sctp_association_free(asoc); | |
1250 | return NULL; | |
1251 | } | |
1252 | ||
1253 | /* Build a cookie representing asoc. | |
1254 | * This INCLUDES the param header needed to put the cookie in the INIT ACK. | |
1255 | */ | |
1256 | static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep, | |
1257 | const struct sctp_association *asoc, | |
1258 | const struct sctp_chunk *init_chunk, | |
1259 | int *cookie_len, | |
1260 | const __u8 *raw_addrs, int addrs_len) | |
1261 | { | |
1262 | sctp_cookie_param_t *retval; | |
1263 | struct sctp_signed_cookie *cookie; | |
1264 | struct scatterlist sg; | |
1265 | int headersize, bodysize; | |
1266 | unsigned int keylen; | |
1267 | char *key; | |
1268 | ||
1269 | headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE; | |
1270 | bodysize = sizeof(struct sctp_cookie) | |
1271 | + ntohs(init_chunk->chunk_hdr->length) + addrs_len; | |
1272 | ||
1273 | /* Pad out the cookie to a multiple to make the signature | |
1274 | * functions simpler to write. | |
1275 | */ | |
1276 | if (bodysize % SCTP_COOKIE_MULTIPLE) | |
1277 | bodysize += SCTP_COOKIE_MULTIPLE | |
1278 | - (bodysize % SCTP_COOKIE_MULTIPLE); | |
1279 | *cookie_len = headersize + bodysize; | |
1280 | ||
1281 | retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC); | |
1282 | ||
1283 | if (!retval) { | |
1284 | *cookie_len = 0; | |
1285 | goto nodata; | |
1286 | } | |
1287 | ||
1288 | /* Clear this memory since we are sending this data structure | |
1289 | * out on the network. | |
1290 | */ | |
1291 | memset(retval, 0x00, *cookie_len); | |
1292 | cookie = (struct sctp_signed_cookie *) retval->body; | |
1293 | ||
1294 | /* Set up the parameter header. */ | |
1295 | retval->p.type = SCTP_PARAM_STATE_COOKIE; | |
1296 | retval->p.length = htons(*cookie_len); | |
1297 | ||
1298 | /* Copy the cookie part of the association itself. */ | |
1299 | cookie->c = asoc->c; | |
1300 | /* Save the raw address list length in the cookie. */ | |
1301 | cookie->c.raw_addr_list_len = addrs_len; | |
1302 | ||
1303 | /* Remember PR-SCTP capability. */ | |
1304 | cookie->c.prsctp_capable = asoc->peer.prsctp_capable; | |
1305 | ||
1306 | /* Save adaption indication in the cookie. */ | |
1307 | cookie->c.adaption_ind = asoc->peer.adaption_ind; | |
1308 | ||
1309 | /* Set an expiration time for the cookie. */ | |
1310 | do_gettimeofday(&cookie->c.expiration); | |
1311 | TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration); | |
1312 | ||
1313 | /* Copy the peer's init packet. */ | |
1314 | memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr, | |
1315 | ntohs(init_chunk->chunk_hdr->length)); | |
1316 | ||
1317 | /* Copy the raw local address list of the association. */ | |
1318 | memcpy((__u8 *)&cookie->c.peer_init[0] + | |
1319 | ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len); | |
1320 | ||
1321 | if (sctp_sk(ep->base.sk)->hmac) { | |
1322 | /* Sign the message. */ | |
1323 | sg.page = virt_to_page(&cookie->c); | |
1324 | sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE; | |
1325 | sg.length = bodysize; | |
1326 | keylen = SCTP_SECRET_SIZE; | |
1327 | key = (char *)ep->secret_key[ep->current_key]; | |
1328 | ||
1329 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, | |
1330 | &sg, 1, cookie->signature); | |
1331 | } | |
1332 | ||
1333 | nodata: | |
1334 | return retval; | |
1335 | } | |
1336 | ||
1337 | /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */ | |
1338 | struct sctp_association *sctp_unpack_cookie( | |
1339 | const struct sctp_endpoint *ep, | |
1340 | const struct sctp_association *asoc, | |
1341 | struct sctp_chunk *chunk, int gfp, | |
1342 | int *error, struct sctp_chunk **errp) | |
1343 | { | |
1344 | struct sctp_association *retval = NULL; | |
1345 | struct sctp_signed_cookie *cookie; | |
1346 | struct sctp_cookie *bear_cookie; | |
1347 | int headersize, bodysize, fixed_size; | |
1348 | __u8 digest[SCTP_SIGNATURE_SIZE]; | |
1349 | struct scatterlist sg; | |
1350 | unsigned int keylen, len; | |
1351 | char *key; | |
1352 | sctp_scope_t scope; | |
1353 | struct sk_buff *skb = chunk->skb; | |
1354 | ||
1355 | headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE; | |
1356 | bodysize = ntohs(chunk->chunk_hdr->length) - headersize; | |
1357 | fixed_size = headersize + sizeof(struct sctp_cookie); | |
1358 | ||
1359 | /* Verify that the chunk looks like it even has a cookie. | |
1360 | * There must be enough room for our cookie and our peer's | |
1361 | * INIT chunk. | |
1362 | */ | |
1363 | len = ntohs(chunk->chunk_hdr->length); | |
1364 | if (len < fixed_size + sizeof(struct sctp_chunkhdr)) | |
1365 | goto malformed; | |
1366 | ||
1367 | /* Verify that the cookie has been padded out. */ | |
1368 | if (bodysize % SCTP_COOKIE_MULTIPLE) | |
1369 | goto malformed; | |
1370 | ||
1371 | /* Process the cookie. */ | |
1372 | cookie = chunk->subh.cookie_hdr; | |
1373 | bear_cookie = &cookie->c; | |
1374 | ||
1375 | if (!sctp_sk(ep->base.sk)->hmac) | |
1376 | goto no_hmac; | |
1377 | ||
1378 | /* Check the signature. */ | |
1379 | keylen = SCTP_SECRET_SIZE; | |
1380 | sg.page = virt_to_page(bear_cookie); | |
1381 | sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE; | |
1382 | sg.length = bodysize; | |
1383 | key = (char *)ep->secret_key[ep->current_key]; | |
1384 | ||
1385 | memset(digest, 0x00, sizeof(digest)); | |
1386 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg, | |
1387 | 1, digest); | |
1388 | ||
1389 | if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) { | |
1390 | /* Try the previous key. */ | |
1391 | key = (char *)ep->secret_key[ep->last_key]; | |
1392 | memset(digest, 0x00, sizeof(digest)); | |
1393 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, | |
1394 | &sg, 1, digest); | |
1395 | ||
1396 | if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) { | |
1397 | /* Yikes! Still bad signature! */ | |
1398 | *error = -SCTP_IERROR_BAD_SIG; | |
1399 | goto fail; | |
1400 | } | |
1401 | } | |
1402 | ||
1403 | no_hmac: | |
1404 | /* IG Section 2.35.2: | |
1405 | * 3) Compare the port numbers and the verification tag contained | |
1406 | * within the COOKIE ECHO chunk to the actual port numbers and the | |
1407 | * verification tag within the SCTP common header of the received | |
1408 | * packet. If these values do not match the packet MUST be silently | |
1409 | * discarded, | |
1410 | */ | |
1411 | if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) { | |
1412 | *error = -SCTP_IERROR_BAD_TAG; | |
1413 | goto fail; | |
1414 | } | |
1415 | ||
1416 | if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port || | |
1417 | ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) { | |
1418 | *error = -SCTP_IERROR_BAD_PORTS; | |
1419 | goto fail; | |
1420 | } | |
1421 | ||
1422 | /* Check to see if the cookie is stale. If there is already | |
1423 | * an association, there is no need to check cookie's expiration | |
1424 | * for init collision case of lost COOKIE ACK. | |
1425 | */ | |
1426 | if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) { | |
1427 | __u16 len; | |
1428 | /* | |
1429 | * Section 3.3.10.3 Stale Cookie Error (3) | |
1430 | * | |
1431 | * Cause of error | |
1432 | * --------------- | |
1433 | * Stale Cookie Error: Indicates the receipt of a valid State | |
1434 | * Cookie that has expired. | |
1435 | */ | |
1436 | len = ntohs(chunk->chunk_hdr->length); | |
1437 | *errp = sctp_make_op_error_space(asoc, chunk, len); | |
1438 | if (*errp) { | |
1439 | suseconds_t usecs = (skb->stamp.tv_sec - | |
1440 | bear_cookie->expiration.tv_sec) * 1000000L + | |
1441 | skb->stamp.tv_usec - | |
1442 | bear_cookie->expiration.tv_usec; | |
1443 | ||
1444 | usecs = htonl(usecs); | |
1445 | sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE, | |
1446 | &usecs, sizeof(usecs)); | |
1447 | *error = -SCTP_IERROR_STALE_COOKIE; | |
1448 | } else | |
1449 | *error = -SCTP_IERROR_NOMEM; | |
1450 | ||
1451 | goto fail; | |
1452 | } | |
1453 | ||
1454 | /* Make a new base association. */ | |
1455 | scope = sctp_scope(sctp_source(chunk)); | |
1456 | retval = sctp_association_new(ep, ep->base.sk, scope, gfp); | |
1457 | if (!retval) { | |
1458 | *error = -SCTP_IERROR_NOMEM; | |
1459 | goto fail; | |
1460 | } | |
1461 | ||
1462 | /* Set up our peer's port number. */ | |
1463 | retval->peer.port = ntohs(chunk->sctp_hdr->source); | |
1464 | ||
1465 | /* Populate the association from the cookie. */ | |
1466 | memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie)); | |
1467 | ||
1468 | if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie, | |
1469 | GFP_ATOMIC) < 0) { | |
1470 | *error = -SCTP_IERROR_NOMEM; | |
1471 | goto fail; | |
1472 | } | |
1473 | ||
1474 | /* Also, add the destination address. */ | |
1475 | if (list_empty(&retval->base.bind_addr.address_list)) { | |
1476 | sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest, | |
1477 | GFP_ATOMIC); | |
1478 | } | |
1479 | ||
1480 | retval->next_tsn = retval->c.initial_tsn; | |
1481 | retval->ctsn_ack_point = retval->next_tsn - 1; | |
1482 | retval->addip_serial = retval->c.initial_tsn; | |
1483 | retval->adv_peer_ack_point = retval->ctsn_ack_point; | |
1484 | retval->peer.prsctp_capable = retval->c.prsctp_capable; | |
1485 | retval->peer.adaption_ind = retval->c.adaption_ind; | |
1486 | ||
1487 | /* The INIT stuff will be done by the side effects. */ | |
1488 | return retval; | |
1489 | ||
1490 | fail: | |
1491 | if (retval) | |
1492 | sctp_association_free(retval); | |
1493 | ||
1494 | return NULL; | |
1495 | ||
1496 | malformed: | |
1497 | /* Yikes! The packet is either corrupt or deliberately | |
1498 | * malformed. | |
1499 | */ | |
1500 | *error = -SCTP_IERROR_MALFORMED; | |
1501 | goto fail; | |
1502 | } | |
1503 | ||
1504 | /******************************************************************** | |
1505 | * 3rd Level Abstractions | |
1506 | ********************************************************************/ | |
1507 | ||
1508 | struct __sctp_missing { | |
1509 | __u32 num_missing; | |
1510 | __u16 type; | |
1511 | } __attribute__((packed)); | |
1512 | ||
1513 | /* | |
1514 | * Report a missing mandatory parameter. | |
1515 | */ | |
1516 | static int sctp_process_missing_param(const struct sctp_association *asoc, | |
1517 | sctp_param_t paramtype, | |
1518 | struct sctp_chunk *chunk, | |
1519 | struct sctp_chunk **errp) | |
1520 | { | |
1521 | struct __sctp_missing report; | |
1522 | __u16 len; | |
1523 | ||
1524 | len = WORD_ROUND(sizeof(report)); | |
1525 | ||
1526 | /* Make an ERROR chunk, preparing enough room for | |
1527 | * returning multiple unknown parameters. | |
1528 | */ | |
1529 | if (!*errp) | |
1530 | *errp = sctp_make_op_error_space(asoc, chunk, len); | |
1531 | ||
1532 | if (*errp) { | |
1533 | report.num_missing = htonl(1); | |
1534 | report.type = paramtype; | |
1535 | sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, | |
1536 | &report, sizeof(report)); | |
1537 | } | |
1538 | ||
1539 | /* Stop processing this chunk. */ | |
1540 | return 0; | |
1541 | } | |
1542 | ||
1543 | /* Report an Invalid Mandatory Parameter. */ | |
1544 | static int sctp_process_inv_mandatory(const struct sctp_association *asoc, | |
1545 | struct sctp_chunk *chunk, | |
1546 | struct sctp_chunk **errp) | |
1547 | { | |
1548 | /* Invalid Mandatory Parameter Error has no payload. */ | |
1549 | ||
1550 | if (!*errp) | |
1551 | *errp = sctp_make_op_error_space(asoc, chunk, 0); | |
1552 | ||
1553 | if (*errp) | |
1554 | sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0); | |
1555 | ||
1556 | /* Stop processing this chunk. */ | |
1557 | return 0; | |
1558 | } | |
1559 | ||
1560 | static int sctp_process_inv_paramlength(const struct sctp_association *asoc, | |
1561 | struct sctp_paramhdr *param, | |
1562 | const struct sctp_chunk *chunk, | |
1563 | struct sctp_chunk **errp) | |
1564 | { | |
1565 | char error[] = "The following parameter had invalid length:"; | |
1566 | size_t payload_len = WORD_ROUND(sizeof(error)) + | |
1567 | sizeof(sctp_paramhdr_t); | |
1568 | ||
1569 | ||
1570 | /* Create an error chunk and fill it in with our payload. */ | |
1571 | if (!*errp) | |
1572 | *errp = sctp_make_op_error_space(asoc, chunk, payload_len); | |
1573 | ||
1574 | if (*errp) { | |
1575 | sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error, | |
1576 | sizeof(error)); | |
1577 | sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param); | |
1578 | } | |
1579 | ||
1580 | return 0; | |
1581 | } | |
1582 | ||
1583 | ||
1584 | /* Do not attempt to handle the HOST_NAME parm. However, do | |
1585 | * send back an indicator to the peer. | |
1586 | */ | |
1587 | static int sctp_process_hn_param(const struct sctp_association *asoc, | |
1588 | union sctp_params param, | |
1589 | struct sctp_chunk *chunk, | |
1590 | struct sctp_chunk **errp) | |
1591 | { | |
1592 | __u16 len = ntohs(param.p->length); | |
1593 | ||
1594 | /* Make an ERROR chunk. */ | |
1595 | if (!*errp) | |
1596 | *errp = sctp_make_op_error_space(asoc, chunk, len); | |
1597 | ||
1598 | if (*errp) | |
1599 | sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, | |
1600 | param.v, len); | |
1601 | ||
1602 | /* Stop processing this chunk. */ | |
1603 | return 0; | |
1604 | } | |
1605 | ||
1606 | /* RFC 3.2.1 & the Implementers Guide 2.2. | |
1607 | * | |
1608 | * The Parameter Types are encoded such that the | |
1609 | * highest-order two bits specify the action that must be | |
1610 | * taken if the processing endpoint does not recognize the | |
1611 | * Parameter Type. | |
1612 | * | |
1613 | * 00 - Stop processing this SCTP chunk and discard it, | |
1614 | * do not process any further chunks within it. | |
1615 | * | |
1616 | * 01 - Stop processing this SCTP chunk and discard it, | |
1617 | * do not process any further chunks within it, and report | |
1618 | * the unrecognized parameter in an 'Unrecognized | |
1619 | * Parameter Type' (in either an ERROR or in the INIT ACK). | |
1620 | * | |
1621 | * 10 - Skip this parameter and continue processing. | |
1622 | * | |
1623 | * 11 - Skip this parameter and continue processing but | |
1624 | * report the unrecognized parameter in an | |
1625 | * 'Unrecognized Parameter Type' (in either an ERROR or in | |
1626 | * the INIT ACK). | |
1627 | * | |
1628 | * Return value: | |
1629 | * 0 - discard the chunk | |
1630 | * 1 - continue with the chunk | |
1631 | */ | |
1632 | static int sctp_process_unk_param(const struct sctp_association *asoc, | |
1633 | union sctp_params param, | |
1634 | struct sctp_chunk *chunk, | |
1635 | struct sctp_chunk **errp) | |
1636 | { | |
1637 | int retval = 1; | |
1638 | ||
1639 | switch (param.p->type & SCTP_PARAM_ACTION_MASK) { | |
1640 | case SCTP_PARAM_ACTION_DISCARD: | |
1641 | retval = 0; | |
1642 | break; | |
1643 | case SCTP_PARAM_ACTION_DISCARD_ERR: | |
1644 | retval = 0; | |
1645 | /* Make an ERROR chunk, preparing enough room for | |
1646 | * returning multiple unknown parameters. | |
1647 | */ | |
1648 | if (NULL == *errp) | |
1649 | *errp = sctp_make_op_error_space(asoc, chunk, | |
1650 | ntohs(chunk->chunk_hdr->length)); | |
1651 | ||
1652 | if (*errp) | |
1653 | sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM, | |
1654 | param.v, | |
1655 | WORD_ROUND(ntohs(param.p->length))); | |
1656 | ||
1657 | break; | |
1658 | case SCTP_PARAM_ACTION_SKIP: | |
1659 | break; | |
1660 | case SCTP_PARAM_ACTION_SKIP_ERR: | |
1661 | /* Make an ERROR chunk, preparing enough room for | |
1662 | * returning multiple unknown parameters. | |
1663 | */ | |
1664 | if (NULL == *errp) | |
1665 | *errp = sctp_make_op_error_space(asoc, chunk, | |
1666 | ntohs(chunk->chunk_hdr->length)); | |
1667 | ||
1668 | if (*errp) { | |
1669 | sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM, | |
1670 | param.v, | |
1671 | WORD_ROUND(ntohs(param.p->length))); | |
1672 | } else { | |
1673 | /* If there is no memory for generating the ERROR | |
1674 | * report as specified, an ABORT will be triggered | |
1675 | * to the peer and the association won't be | |
1676 | * established. | |
1677 | */ | |
1678 | retval = 0; | |
1679 | } | |
1680 | ||
1681 | break; | |
1682 | default: | |
1683 | break; | |
1684 | } | |
1685 | ||
1686 | return retval; | |
1687 | } | |
1688 | ||
1689 | /* Find unrecognized parameters in the chunk. | |
1690 | * Return values: | |
1691 | * 0 - discard the chunk | |
1692 | * 1 - continue with the chunk | |
1693 | */ | |
1694 | static int sctp_verify_param(const struct sctp_association *asoc, | |
1695 | union sctp_params param, | |
1696 | sctp_cid_t cid, | |
1697 | struct sctp_chunk *chunk, | |
1698 | struct sctp_chunk **err_chunk) | |
1699 | { | |
1700 | int retval = 1; | |
1701 | ||
1702 | /* FIXME - This routine is not looking at each parameter per the | |
1703 | * chunk type, i.e., unrecognized parameters should be further | |
1704 | * identified based on the chunk id. | |
1705 | */ | |
1706 | ||
1707 | switch (param.p->type) { | |
1708 | case SCTP_PARAM_IPV4_ADDRESS: | |
1709 | case SCTP_PARAM_IPV6_ADDRESS: | |
1710 | case SCTP_PARAM_COOKIE_PRESERVATIVE: | |
1711 | case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES: | |
1712 | case SCTP_PARAM_STATE_COOKIE: | |
1713 | case SCTP_PARAM_HEARTBEAT_INFO: | |
1714 | case SCTP_PARAM_UNRECOGNIZED_PARAMETERS: | |
1715 | case SCTP_PARAM_ECN_CAPABLE: | |
1716 | case SCTP_PARAM_ADAPTION_LAYER_IND: | |
1717 | break; | |
1718 | ||
1719 | case SCTP_PARAM_HOST_NAME_ADDRESS: | |
1720 | /* Tell the peer, we won't support this param. */ | |
1721 | return sctp_process_hn_param(asoc, param, chunk, err_chunk); | |
1722 | case SCTP_PARAM_FWD_TSN_SUPPORT: | |
1723 | if (sctp_prsctp_enable) | |
1724 | break; | |
1725 | /* Fall Through */ | |
1726 | default: | |
1727 | SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n", | |
1728 | ntohs(param.p->type), cid); | |
1729 | return sctp_process_unk_param(asoc, param, chunk, err_chunk); | |
1730 | ||
1731 | break; | |
1732 | } | |
1733 | return retval; | |
1734 | } | |
1735 | ||
1736 | /* Verify the INIT packet before we process it. */ | |
1737 | int sctp_verify_init(const struct sctp_association *asoc, | |
1738 | sctp_cid_t cid, | |
1739 | sctp_init_chunk_t *peer_init, | |
1740 | struct sctp_chunk *chunk, | |
1741 | struct sctp_chunk **errp) | |
1742 | { | |
1743 | union sctp_params param; | |
1744 | int has_cookie = 0; | |
1745 | ||
1746 | /* Verify stream values are non-zero. */ | |
1747 | if ((0 == peer_init->init_hdr.num_outbound_streams) || | |
1748 | (0 == peer_init->init_hdr.num_inbound_streams)) { | |
1749 | ||
1750 | sctp_process_inv_mandatory(asoc, chunk, errp); | |
1751 | return 0; | |
1752 | } | |
1753 | ||
1754 | /* Check for missing mandatory parameters. */ | |
1755 | sctp_walk_params(param, peer_init, init_hdr.params) { | |
1756 | ||
1757 | if (SCTP_PARAM_STATE_COOKIE == param.p->type) | |
1758 | has_cookie = 1; | |
1759 | ||
1760 | } /* for (loop through all parameters) */ | |
1761 | ||
1762 | /* There is a possibility that a parameter length was bad and | |
1763 | * in that case we would have stoped walking the parameters. | |
1764 | * The current param.p would point at the bad one. | |
1765 | * Current consensus on the mailing list is to generate a PROTOCOL | |
1766 | * VIOLATION error. We build the ERROR chunk here and let the normal | |
1767 | * error handling code build and send the packet. | |
1768 | */ | |
1769 | if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) { | |
1770 | sctp_process_inv_paramlength(asoc, param.p, chunk, errp); | |
1771 | return 0; | |
1772 | } | |
1773 | ||
1774 | /* The only missing mandatory param possible today is | |
1775 | * the state cookie for an INIT-ACK chunk. | |
1776 | */ | |
1777 | if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) { | |
1778 | sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE, | |
1779 | chunk, errp); | |
1780 | return 0; | |
1781 | } | |
1782 | ||
1783 | /* Find unrecognized parameters. */ | |
1784 | ||
1785 | sctp_walk_params(param, peer_init, init_hdr.params) { | |
1786 | ||
1787 | if (!sctp_verify_param(asoc, param, cid, chunk, errp)) { | |
1788 | if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type) | |
1789 | return 0; | |
1790 | else | |
1791 | return 1; | |
1792 | } | |
1793 | ||
1794 | } /* for (loop through all parameters) */ | |
1795 | ||
1796 | return 1; | |
1797 | } | |
1798 | ||
1799 | /* Unpack the parameters in an INIT packet into an association. | |
1800 | * Returns 0 on failure, else success. | |
1801 | * FIXME: This is an association method. | |
1802 | */ | |
1803 | int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid, | |
1804 | const union sctp_addr *peer_addr, | |
1805 | sctp_init_chunk_t *peer_init, int gfp) | |
1806 | { | |
1807 | union sctp_params param; | |
1808 | struct sctp_transport *transport; | |
1809 | struct list_head *pos, *temp; | |
1810 | char *cookie; | |
1811 | ||
1812 | /* We must include the address that the INIT packet came from. | |
1813 | * This is the only address that matters for an INIT packet. | |
1814 | * When processing a COOKIE ECHO, we retrieve the from address | |
1815 | * of the INIT from the cookie. | |
1816 | */ | |
1817 | ||
1818 | /* This implementation defaults to making the first transport | |
1819 | * added as the primary transport. The source address seems to | |
1820 | * be a a better choice than any of the embedded addresses. | |
1821 | */ | |
1822 | if (peer_addr) | |
1823 | if(!sctp_assoc_add_peer(asoc, peer_addr, gfp)) | |
1824 | goto nomem; | |
1825 | ||
1826 | /* Process the initialization parameters. */ | |
1827 | ||
1828 | sctp_walk_params(param, peer_init, init_hdr.params) { | |
1829 | ||
1830 | if (!sctp_process_param(asoc, param, peer_addr, gfp)) | |
1831 | goto clean_up; | |
1832 | } | |
1833 | ||
1834 | /* The fixed INIT headers are always in network byte | |
1835 | * order. | |
1836 | */ | |
1837 | asoc->peer.i.init_tag = | |
1838 | ntohl(peer_init->init_hdr.init_tag); | |
1839 | asoc->peer.i.a_rwnd = | |
1840 | ntohl(peer_init->init_hdr.a_rwnd); | |
1841 | asoc->peer.i.num_outbound_streams = | |
1842 | ntohs(peer_init->init_hdr.num_outbound_streams); | |
1843 | asoc->peer.i.num_inbound_streams = | |
1844 | ntohs(peer_init->init_hdr.num_inbound_streams); | |
1845 | asoc->peer.i.initial_tsn = | |
1846 | ntohl(peer_init->init_hdr.initial_tsn); | |
1847 | ||
1848 | /* Apply the upper bounds for output streams based on peer's | |
1849 | * number of inbound streams. | |
1850 | */ | |
1851 | if (asoc->c.sinit_num_ostreams > | |
1852 | ntohs(peer_init->init_hdr.num_inbound_streams)) { | |
1853 | asoc->c.sinit_num_ostreams = | |
1854 | ntohs(peer_init->init_hdr.num_inbound_streams); | |
1855 | } | |
1856 | ||
1857 | if (asoc->c.sinit_max_instreams > | |
1858 | ntohs(peer_init->init_hdr.num_outbound_streams)) { | |
1859 | asoc->c.sinit_max_instreams = | |
1860 | ntohs(peer_init->init_hdr.num_outbound_streams); | |
1861 | } | |
1862 | ||
1863 | /* Copy Initiation tag from INIT to VT_peer in cookie. */ | |
1864 | asoc->c.peer_vtag = asoc->peer.i.init_tag; | |
1865 | ||
1866 | /* Peer Rwnd : Current calculated value of the peer's rwnd. */ | |
1867 | asoc->peer.rwnd = asoc->peer.i.a_rwnd; | |
1868 | ||
1869 | /* Copy cookie in case we need to resend COOKIE-ECHO. */ | |
1870 | cookie = asoc->peer.cookie; | |
1871 | if (cookie) { | |
1872 | asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp); | |
1873 | if (!asoc->peer.cookie) | |
1874 | goto clean_up; | |
1875 | memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len); | |
1876 | } | |
1877 | ||
1878 | /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily | |
1879 | * high (for example, implementations MAY use the size of the receiver | |
1880 | * advertised window). | |
1881 | */ | |
1882 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
1883 | transport = list_entry(pos, struct sctp_transport, transports); | |
1884 | transport->ssthresh = asoc->peer.i.a_rwnd; | |
1885 | } | |
1886 | ||
1887 | /* Set up the TSN tracking pieces. */ | |
1888 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, | |
1889 | asoc->peer.i.initial_tsn); | |
1890 | ||
1891 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
1892 | * | |
1893 | * The stream sequence number in all the streams shall start | |
1894 | * from 0 when the association is established. Also, when the | |
1895 | * stream sequence number reaches the value 65535 the next | |
1896 | * stream sequence number shall be set to 0. | |
1897 | */ | |
1898 | ||
1899 | /* Allocate storage for the negotiated streams if it is not a temporary * association. | |
1900 | */ | |
1901 | if (!asoc->temp) { | |
1902 | int assoc_id; | |
1903 | int error; | |
1904 | ||
1905 | asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams, | |
1906 | asoc->c.sinit_num_ostreams, gfp); | |
1907 | if (!asoc->ssnmap) | |
1908 | goto clean_up; | |
1909 | ||
1910 | retry: | |
1911 | if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp))) | |
1912 | goto clean_up; | |
1913 | spin_lock_bh(&sctp_assocs_id_lock); | |
1914 | error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1, | |
1915 | &assoc_id); | |
1916 | spin_unlock_bh(&sctp_assocs_id_lock); | |
1917 | if (error == -EAGAIN) | |
1918 | goto retry; | |
1919 | else if (error) | |
1920 | goto clean_up; | |
1921 | ||
1922 | asoc->assoc_id = (sctp_assoc_t) assoc_id; | |
1923 | } | |
1924 | ||
1925 | /* ADDIP Section 4.1 ASCONF Chunk Procedures | |
1926 | * | |
1927 | * When an endpoint has an ASCONF signaled change to be sent to the | |
1928 | * remote endpoint it should do the following: | |
1929 | * ... | |
1930 | * A2) A serial number should be assigned to the Chunk. The serial | |
1931 | * number should be a monotonically increasing number. All serial | |
1932 | * numbers are defined to be initialized at the start of the | |
1933 | * association to the same value as the Initial TSN. | |
1934 | */ | |
1935 | asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1; | |
1936 | return 1; | |
1937 | ||
1938 | clean_up: | |
1939 | /* Release the transport structures. */ | |
1940 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { | |
1941 | transport = list_entry(pos, struct sctp_transport, transports); | |
1942 | list_del_init(pos); | |
1943 | sctp_transport_free(transport); | |
1944 | } | |
1945 | nomem: | |
1946 | return 0; | |
1947 | } | |
1948 | ||
1949 | ||
1950 | /* Update asoc with the option described in param. | |
1951 | * | |
1952 | * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT | |
1953 | * | |
1954 | * asoc is the association to update. | |
1955 | * param is the variable length parameter to use for update. | |
1956 | * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO. | |
1957 | * If the current packet is an INIT we want to minimize the amount of | |
1958 | * work we do. In particular, we should not build transport | |
1959 | * structures for the addresses. | |
1960 | */ | |
1961 | static int sctp_process_param(struct sctp_association *asoc, | |
1962 | union sctp_params param, | |
1963 | const union sctp_addr *peer_addr, | |
1964 | int gfp) | |
1965 | { | |
1966 | union sctp_addr addr; | |
1967 | int i; | |
1968 | __u16 sat; | |
1969 | int retval = 1; | |
1970 | sctp_scope_t scope; | |
1971 | time_t stale; | |
1972 | struct sctp_af *af; | |
1973 | ||
1974 | /* We maintain all INIT parameters in network byte order all the | |
1975 | * time. This allows us to not worry about whether the parameters | |
1976 | * came from a fresh INIT, and INIT ACK, or were stored in a cookie. | |
1977 | */ | |
1978 | switch (param.p->type) { | |
1979 | case SCTP_PARAM_IPV6_ADDRESS: | |
1980 | if (PF_INET6 != asoc->base.sk->sk_family) | |
1981 | break; | |
1982 | /* Fall through. */ | |
1983 | case SCTP_PARAM_IPV4_ADDRESS: | |
1984 | af = sctp_get_af_specific(param_type2af(param.p->type)); | |
1985 | af->from_addr_param(&addr, param.addr, asoc->peer.port, 0); | |
1986 | scope = sctp_scope(peer_addr); | |
1987 | if (sctp_in_scope(&addr, scope)) | |
1988 | if (!sctp_assoc_add_peer(asoc, &addr, gfp)) | |
1989 | return 0; | |
1990 | break; | |
1991 | ||
1992 | case SCTP_PARAM_COOKIE_PRESERVATIVE: | |
1993 | if (!sctp_cookie_preserve_enable) | |
1994 | break; | |
1995 | ||
1996 | stale = ntohl(param.life->lifespan_increment); | |
1997 | ||
1998 | /* Suggested Cookie Life span increment's unit is msec, | |
1999 | * (1/1000sec). | |
2000 | */ | |
2001 | asoc->cookie_life.tv_sec += stale / 1000; | |
2002 | asoc->cookie_life.tv_usec += (stale % 1000) * 1000; | |
2003 | break; | |
2004 | ||
2005 | case SCTP_PARAM_HOST_NAME_ADDRESS: | |
2006 | SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n"); | |
2007 | break; | |
2008 | ||
2009 | case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES: | |
2010 | /* Turn off the default values first so we'll know which | |
2011 | * ones are really set by the peer. | |
2012 | */ | |
2013 | asoc->peer.ipv4_address = 0; | |
2014 | asoc->peer.ipv6_address = 0; | |
2015 | ||
2016 | /* Cycle through address types; avoid divide by 0. */ | |
2017 | sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t); | |
2018 | if (sat) | |
2019 | sat /= sizeof(__u16); | |
2020 | ||
2021 | for (i = 0; i < sat; ++i) { | |
2022 | switch (param.sat->types[i]) { | |
2023 | case SCTP_PARAM_IPV4_ADDRESS: | |
2024 | asoc->peer.ipv4_address = 1; | |
2025 | break; | |
2026 | ||
2027 | case SCTP_PARAM_IPV6_ADDRESS: | |
2028 | asoc->peer.ipv6_address = 1; | |
2029 | break; | |
2030 | ||
2031 | case SCTP_PARAM_HOST_NAME_ADDRESS: | |
2032 | asoc->peer.hostname_address = 1; | |
2033 | break; | |
2034 | ||
2035 | default: /* Just ignore anything else. */ | |
2036 | break; | |
2037 | }; | |
2038 | } | |
2039 | break; | |
2040 | ||
2041 | case SCTP_PARAM_STATE_COOKIE: | |
2042 | asoc->peer.cookie_len = | |
2043 | ntohs(param.p->length) - sizeof(sctp_paramhdr_t); | |
2044 | asoc->peer.cookie = param.cookie->body; | |
2045 | break; | |
2046 | ||
2047 | case SCTP_PARAM_HEARTBEAT_INFO: | |
2048 | /* Would be odd to receive, but it causes no problems. */ | |
2049 | break; | |
2050 | ||
2051 | case SCTP_PARAM_UNRECOGNIZED_PARAMETERS: | |
2052 | /* Rejected during verify stage. */ | |
2053 | break; | |
2054 | ||
2055 | case SCTP_PARAM_ECN_CAPABLE: | |
2056 | asoc->peer.ecn_capable = 1; | |
2057 | break; | |
2058 | ||
2059 | case SCTP_PARAM_ADAPTION_LAYER_IND: | |
2060 | asoc->peer.adaption_ind = param.aind->adaption_ind; | |
2061 | break; | |
2062 | ||
2063 | case SCTP_PARAM_FWD_TSN_SUPPORT: | |
2064 | if (sctp_prsctp_enable) { | |
2065 | asoc->peer.prsctp_capable = 1; | |
2066 | break; | |
2067 | } | |
2068 | /* Fall Through */ | |
2069 | default: | |
2070 | /* Any unrecognized parameters should have been caught | |
2071 | * and handled by sctp_verify_param() which should be | |
2072 | * called prior to this routine. Simply log the error | |
2073 | * here. | |
2074 | */ | |
2075 | SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n", | |
2076 | ntohs(param.p->type), asoc); | |
2077 | break; | |
2078 | }; | |
2079 | ||
2080 | return retval; | |
2081 | } | |
2082 | ||
2083 | /* Select a new verification tag. */ | |
2084 | __u32 sctp_generate_tag(const struct sctp_endpoint *ep) | |
2085 | { | |
2086 | /* I believe that this random number generator complies with RFC1750. | |
2087 | * A tag of 0 is reserved for special cases (e.g. INIT). | |
2088 | */ | |
2089 | __u32 x; | |
2090 | ||
2091 | do { | |
2092 | get_random_bytes(&x, sizeof(__u32)); | |
2093 | } while (x == 0); | |
2094 | ||
2095 | return x; | |
2096 | } | |
2097 | ||
2098 | /* Select an initial TSN to send during startup. */ | |
2099 | __u32 sctp_generate_tsn(const struct sctp_endpoint *ep) | |
2100 | { | |
2101 | __u32 retval; | |
2102 | ||
2103 | get_random_bytes(&retval, sizeof(__u32)); | |
2104 | return retval; | |
2105 | } | |
2106 | ||
2107 | /* | |
2108 | * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF) | |
2109 | * 0 1 2 3 | |
2110 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
2111 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2112 | * | Type = 0xC1 | Chunk Flags | Chunk Length | | |
2113 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2114 | * | Serial Number | | |
2115 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2116 | * | Address Parameter | | |
2117 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2118 | * | ASCONF Parameter #1 | | |
2119 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2120 | * \ \ | |
2121 | * / .... / | |
2122 | * \ \ | |
2123 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2124 | * | ASCONF Parameter #N | | |
2125 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2126 | * | |
2127 | * Address Parameter and other parameter will not be wrapped in this function | |
2128 | */ | |
2129 | static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc, | |
2130 | union sctp_addr *addr, | |
2131 | int vparam_len) | |
2132 | { | |
2133 | sctp_addiphdr_t asconf; | |
2134 | struct sctp_chunk *retval; | |
2135 | int length = sizeof(asconf) + vparam_len; | |
2136 | union sctp_addr_param addrparam; | |
2137 | int addrlen; | |
2138 | struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family); | |
2139 | ||
2140 | addrlen = af->to_addr_param(addr, &addrparam); | |
2141 | if (!addrlen) | |
2142 | return NULL; | |
2143 | length += addrlen; | |
2144 | ||
2145 | /* Create the chunk. */ | |
2146 | retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length); | |
2147 | if (!retval) | |
2148 | return NULL; | |
2149 | ||
2150 | asconf.serial = htonl(asoc->addip_serial++); | |
2151 | ||
2152 | retval->subh.addip_hdr = | |
2153 | sctp_addto_chunk(retval, sizeof(asconf), &asconf); | |
2154 | retval->param_hdr.v = | |
2155 | sctp_addto_chunk(retval, addrlen, &addrparam); | |
2156 | ||
2157 | return retval; | |
2158 | } | |
2159 | ||
2160 | /* ADDIP | |
2161 | * 3.2.1 Add IP Address | |
2162 | * 0 1 2 3 | |
2163 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
2164 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2165 | * | Type = 0xC001 | Length = Variable | | |
2166 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2167 | * | ASCONF-Request Correlation ID | | |
2168 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2169 | * | Address Parameter | | |
2170 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2171 | * | |
2172 | * 3.2.2 Delete IP Address | |
2173 | * 0 1 2 3 | |
2174 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
2175 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2176 | * | Type = 0xC002 | Length = Variable | | |
2177 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2178 | * | ASCONF-Request Correlation ID | | |
2179 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2180 | * | Address Parameter | | |
2181 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2182 | * | |
2183 | */ | |
2184 | struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc, | |
2185 | union sctp_addr *laddr, | |
2186 | struct sockaddr *addrs, | |
2187 | int addrcnt, | |
2188 | __u16 flags) | |
2189 | { | |
2190 | sctp_addip_param_t param; | |
2191 | struct sctp_chunk *retval; | |
2192 | union sctp_addr_param addr_param; | |
2193 | union sctp_addr *addr; | |
2194 | void *addr_buf; | |
2195 | struct sctp_af *af; | |
2196 | int paramlen = sizeof(param); | |
2197 | int addr_param_len = 0; | |
2198 | int totallen = 0; | |
2199 | int i; | |
2200 | ||
2201 | /* Get total length of all the address parameters. */ | |
2202 | addr_buf = addrs; | |
2203 | for (i = 0; i < addrcnt; i++) { | |
2204 | addr = (union sctp_addr *)addr_buf; | |
2205 | af = sctp_get_af_specific(addr->v4.sin_family); | |
2206 | addr_param_len = af->to_addr_param(addr, &addr_param); | |
2207 | ||
2208 | totallen += paramlen; | |
2209 | totallen += addr_param_len; | |
2210 | ||
2211 | addr_buf += af->sockaddr_len; | |
2212 | } | |
2213 | ||
2214 | /* Create an asconf chunk with the required length. */ | |
2215 | retval = sctp_make_asconf(asoc, laddr, totallen); | |
2216 | if (!retval) | |
2217 | return NULL; | |
2218 | ||
2219 | /* Add the address parameters to the asconf chunk. */ | |
2220 | addr_buf = addrs; | |
2221 | for (i = 0; i < addrcnt; i++) { | |
2222 | addr = (union sctp_addr *)addr_buf; | |
2223 | af = sctp_get_af_specific(addr->v4.sin_family); | |
2224 | addr_param_len = af->to_addr_param(addr, &addr_param); | |
2225 | param.param_hdr.type = flags; | |
2226 | param.param_hdr.length = htons(paramlen + addr_param_len); | |
2227 | param.crr_id = i; | |
2228 | ||
2229 | sctp_addto_chunk(retval, paramlen, ¶m); | |
2230 | sctp_addto_chunk(retval, addr_param_len, &addr_param); | |
2231 | ||
2232 | addr_buf += af->sockaddr_len; | |
2233 | } | |
2234 | return retval; | |
2235 | } | |
2236 | ||
2237 | /* ADDIP | |
2238 | * 3.2.4 Set Primary IP Address | |
2239 | * 0 1 2 3 | |
2240 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
2241 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2242 | * | Type =0xC004 | Length = Variable | | |
2243 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2244 | * | ASCONF-Request Correlation ID | | |
2245 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2246 | * | Address Parameter | | |
2247 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2248 | * | |
2249 | * Create an ASCONF chunk with Set Primary IP address parameter. | |
2250 | */ | |
2251 | struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc, | |
2252 | union sctp_addr *addr) | |
2253 | { | |
2254 | sctp_addip_param_t param; | |
2255 | struct sctp_chunk *retval; | |
2256 | int len = sizeof(param); | |
2257 | union sctp_addr_param addrparam; | |
2258 | int addrlen; | |
2259 | struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family); | |
2260 | ||
2261 | addrlen = af->to_addr_param(addr, &addrparam); | |
2262 | if (!addrlen) | |
2263 | return NULL; | |
2264 | len += addrlen; | |
2265 | ||
2266 | /* Create the chunk and make asconf header. */ | |
2267 | retval = sctp_make_asconf(asoc, addr, len); | |
2268 | if (!retval) | |
2269 | return NULL; | |
2270 | ||
2271 | param.param_hdr.type = SCTP_PARAM_SET_PRIMARY; | |
2272 | param.param_hdr.length = htons(len); | |
2273 | param.crr_id = 0; | |
2274 | ||
2275 | sctp_addto_chunk(retval, sizeof(param), ¶m); | |
2276 | sctp_addto_chunk(retval, addrlen, &addrparam); | |
2277 | ||
2278 | return retval; | |
2279 | } | |
2280 | ||
2281 | /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK) | |
2282 | * 0 1 2 3 | |
2283 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 | |
2284 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2285 | * | Type = 0x80 | Chunk Flags | Chunk Length | | |
2286 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2287 | * | Serial Number | | |
2288 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2289 | * | ASCONF Parameter Response#1 | | |
2290 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2291 | * \ \ | |
2292 | * / .... / | |
2293 | * \ \ | |
2294 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2295 | * | ASCONF Parameter Response#N | | |
2296 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | |
2297 | * | |
2298 | * Create an ASCONF_ACK chunk with enough space for the parameter responses. | |
2299 | */ | |
2300 | static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc, | |
2301 | __u32 serial, int vparam_len) | |
2302 | { | |
2303 | sctp_addiphdr_t asconf; | |
2304 | struct sctp_chunk *retval; | |
2305 | int length = sizeof(asconf) + vparam_len; | |
2306 | ||
2307 | /* Create the chunk. */ | |
2308 | retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length); | |
2309 | if (!retval) | |
2310 | return NULL; | |
2311 | ||
2312 | asconf.serial = htonl(serial); | |
2313 | ||
2314 | retval->subh.addip_hdr = | |
2315 | sctp_addto_chunk(retval, sizeof(asconf), &asconf); | |
2316 | ||
2317 | return retval; | |
2318 | } | |
2319 | ||
2320 | /* Add response parameters to an ASCONF_ACK chunk. */ | |
2321 | static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id, | |
2322 | __u16 err_code, sctp_addip_param_t *asconf_param) | |
2323 | { | |
2324 | sctp_addip_param_t ack_param; | |
2325 | sctp_errhdr_t err_param; | |
2326 | int asconf_param_len = 0; | |
2327 | int err_param_len = 0; | |
2328 | __u16 response_type; | |
2329 | ||
2330 | if (SCTP_ERROR_NO_ERROR == err_code) { | |
2331 | response_type = SCTP_PARAM_SUCCESS_REPORT; | |
2332 | } else { | |
2333 | response_type = SCTP_PARAM_ERR_CAUSE; | |
2334 | err_param_len = sizeof(err_param); | |
2335 | if (asconf_param) | |
2336 | asconf_param_len = | |
2337 | ntohs(asconf_param->param_hdr.length); | |
2338 | } | |
2339 | ||
2340 | /* Add Success Indication or Error Cause Indication parameter. */ | |
2341 | ack_param.param_hdr.type = response_type; | |
2342 | ack_param.param_hdr.length = htons(sizeof(ack_param) + | |
2343 | err_param_len + | |
2344 | asconf_param_len); | |
2345 | ack_param.crr_id = crr_id; | |
2346 | sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param); | |
2347 | ||
2348 | if (SCTP_ERROR_NO_ERROR == err_code) | |
2349 | return; | |
2350 | ||
2351 | /* Add Error Cause parameter. */ | |
2352 | err_param.cause = err_code; | |
2353 | err_param.length = htons(err_param_len + asconf_param_len); | |
2354 | sctp_addto_chunk(chunk, err_param_len, &err_param); | |
2355 | ||
2356 | /* Add the failed TLV copied from ASCONF chunk. */ | |
2357 | if (asconf_param) | |
2358 | sctp_addto_chunk(chunk, asconf_param_len, asconf_param); | |
2359 | } | |
2360 | ||
2361 | /* Process a asconf parameter. */ | |
2362 | static __u16 sctp_process_asconf_param(struct sctp_association *asoc, | |
2363 | struct sctp_chunk *asconf, | |
2364 | sctp_addip_param_t *asconf_param) | |
2365 | { | |
2366 | struct sctp_transport *peer; | |
2367 | struct sctp_af *af; | |
2368 | union sctp_addr addr; | |
2369 | struct list_head *pos; | |
2370 | union sctp_addr_param *addr_param; | |
2371 | ||
2372 | addr_param = (union sctp_addr_param *) | |
2373 | ((void *)asconf_param + sizeof(sctp_addip_param_t)); | |
2374 | ||
2375 | af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type)); | |
2376 | if (unlikely(!af)) | |
2377 | return SCTP_ERROR_INV_PARAM; | |
2378 | ||
2379 | af->from_addr_param(&addr, addr_param, asoc->peer.port, 0); | |
2380 | switch (asconf_param->param_hdr.type) { | |
2381 | case SCTP_PARAM_ADD_IP: | |
2382 | /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address | |
2383 | * request and does not have the local resources to add this | |
2384 | * new address to the association, it MUST return an Error | |
2385 | * Cause TLV set to the new error code 'Operation Refused | |
2386 | * Due to Resource Shortage'. | |
2387 | */ | |
2388 | ||
2389 | peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC); | |
2390 | if (!peer) | |
2391 | return SCTP_ERROR_RSRC_LOW; | |
2392 | ||
2393 | /* Start the heartbeat timer. */ | |
2394 | if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer))) | |
2395 | sctp_transport_hold(peer); | |
2396 | break; | |
2397 | case SCTP_PARAM_DEL_IP: | |
2398 | /* ADDIP 4.3 D7) If a request is received to delete the | |
2399 | * last remaining IP address of a peer endpoint, the receiver | |
2400 | * MUST send an Error Cause TLV with the error cause set to the | |
2401 | * new error code 'Request to Delete Last Remaining IP Address'. | |
2402 | */ | |
2403 | pos = asoc->peer.transport_addr_list.next; | |
2404 | if (pos->next == &asoc->peer.transport_addr_list) | |
2405 | return SCTP_ERROR_DEL_LAST_IP; | |
2406 | ||
2407 | /* ADDIP 4.3 D8) If a request is received to delete an IP | |
2408 | * address which is also the source address of the IP packet | |
2409 | * which contained the ASCONF chunk, the receiver MUST reject | |
2410 | * this request. To reject the request the receiver MUST send | |
2411 | * an Error Cause TLV set to the new error code 'Request to | |
2412 | * Delete Source IP Address' | |
2413 | */ | |
2414 | if (sctp_cmp_addr_exact(sctp_source(asconf), &addr)) | |
2415 | return SCTP_ERROR_DEL_SRC_IP; | |
2416 | ||
2417 | sctp_assoc_del_peer(asoc, &addr); | |
2418 | break; | |
2419 | case SCTP_PARAM_SET_PRIMARY: | |
2420 | peer = sctp_assoc_lookup_paddr(asoc, &addr); | |
2421 | if (!peer) | |
2422 | return SCTP_ERROR_INV_PARAM; | |
2423 | ||
2424 | sctp_assoc_set_primary(asoc, peer); | |
2425 | break; | |
2426 | default: | |
2427 | return SCTP_ERROR_INV_PARAM; | |
2428 | break; | |
2429 | } | |
2430 | ||
2431 | return SCTP_ERROR_NO_ERROR; | |
2432 | } | |
2433 | ||
2434 | /* Process an incoming ASCONF chunk with the next expected serial no. and | |
2435 | * return an ASCONF_ACK chunk to be sent in response. | |
2436 | */ | |
2437 | struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc, | |
2438 | struct sctp_chunk *asconf) | |
2439 | { | |
2440 | sctp_addiphdr_t *hdr; | |
2441 | union sctp_addr_param *addr_param; | |
2442 | sctp_addip_param_t *asconf_param; | |
2443 | struct sctp_chunk *asconf_ack; | |
2444 | ||
2445 | __u16 err_code; | |
2446 | int length = 0; | |
2447 | int chunk_len = asconf->skb->len; | |
2448 | __u32 serial; | |
2449 | int all_param_pass = 1; | |
2450 | ||
2451 | hdr = (sctp_addiphdr_t *)asconf->skb->data; | |
2452 | serial = ntohl(hdr->serial); | |
2453 | ||
2454 | /* Skip the addiphdr and store a pointer to address parameter. */ | |
2455 | length = sizeof(sctp_addiphdr_t); | |
2456 | addr_param = (union sctp_addr_param *)(asconf->skb->data + length); | |
2457 | chunk_len -= length; | |
2458 | ||
2459 | /* Skip the address parameter and store a pointer to the first | |
2460 | * asconf paramter. | |
2461 | */ | |
2462 | length = ntohs(addr_param->v4.param_hdr.length); | |
2463 | asconf_param = (sctp_addip_param_t *)((void *)addr_param + length); | |
2464 | chunk_len -= length; | |
2465 | ||
2466 | /* create an ASCONF_ACK chunk. | |
2467 | * Based on the definitions of parameters, we know that the size of | |
2468 | * ASCONF_ACK parameters are less than or equal to the twice of ASCONF | |
2469 | * paramters. | |
2470 | */ | |
2471 | asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2); | |
2472 | if (!asconf_ack) | |
2473 | goto done; | |
2474 | ||
2475 | /* Process the TLVs contained within the ASCONF chunk. */ | |
2476 | while (chunk_len > 0) { | |
2477 | err_code = sctp_process_asconf_param(asoc, asconf, | |
2478 | asconf_param); | |
2479 | /* ADDIP 4.1 A7) | |
2480 | * If an error response is received for a TLV parameter, | |
2481 | * all TLVs with no response before the failed TLV are | |
2482 | * considered successful if not reported. All TLVs after | |
2483 | * the failed response are considered unsuccessful unless | |
2484 | * a specific success indication is present for the parameter. | |
2485 | */ | |
2486 | if (SCTP_ERROR_NO_ERROR != err_code) | |
2487 | all_param_pass = 0; | |
2488 | ||
2489 | if (!all_param_pass) | |
2490 | sctp_add_asconf_response(asconf_ack, | |
2491 | asconf_param->crr_id, err_code, | |
2492 | asconf_param); | |
2493 | ||
2494 | /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add | |
2495 | * an IP address sends an 'Out of Resource' in its response, it | |
2496 | * MUST also fail any subsequent add or delete requests bundled | |
2497 | * in the ASCONF. | |
2498 | */ | |
2499 | if (SCTP_ERROR_RSRC_LOW == err_code) | |
2500 | goto done; | |
2501 | ||
2502 | /* Move to the next ASCONF param. */ | |
2503 | length = ntohs(asconf_param->param_hdr.length); | |
2504 | asconf_param = (sctp_addip_param_t *)((void *)asconf_param + | |
2505 | length); | |
2506 | chunk_len -= length; | |
2507 | } | |
2508 | ||
2509 | done: | |
2510 | asoc->peer.addip_serial++; | |
2511 | ||
2512 | /* If we are sending a new ASCONF_ACK hold a reference to it in assoc | |
2513 | * after freeing the reference to old asconf ack if any. | |
2514 | */ | |
2515 | if (asconf_ack) { | |
2516 | if (asoc->addip_last_asconf_ack) | |
2517 | sctp_chunk_free(asoc->addip_last_asconf_ack); | |
2518 | ||
2519 | sctp_chunk_hold(asconf_ack); | |
2520 | asoc->addip_last_asconf_ack = asconf_ack; | |
2521 | } | |
2522 | ||
2523 | return asconf_ack; | |
2524 | } | |
2525 | ||
2526 | /* Process a asconf parameter that is successfully acked. */ | |
2527 | static int sctp_asconf_param_success(struct sctp_association *asoc, | |
2528 | sctp_addip_param_t *asconf_param) | |
2529 | { | |
2530 | struct sctp_af *af; | |
2531 | union sctp_addr addr; | |
2532 | struct sctp_bind_addr *bp = &asoc->base.bind_addr; | |
2533 | union sctp_addr_param *addr_param; | |
2534 | struct list_head *pos; | |
2535 | struct sctp_transport *transport; | |
2536 | int retval = 0; | |
2537 | ||
2538 | addr_param = (union sctp_addr_param *) | |
2539 | ((void *)asconf_param + sizeof(sctp_addip_param_t)); | |
2540 | ||
2541 | /* We have checked the packet before, so we do not check again. */ | |
2542 | af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type)); | |
2543 | af->from_addr_param(&addr, addr_param, bp->port, 0); | |
2544 | ||
2545 | switch (asconf_param->param_hdr.type) { | |
2546 | case SCTP_PARAM_ADD_IP: | |
2547 | sctp_local_bh_disable(); | |
2548 | sctp_write_lock(&asoc->base.addr_lock); | |
2549 | retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC); | |
2550 | sctp_write_unlock(&asoc->base.addr_lock); | |
2551 | sctp_local_bh_enable(); | |
2552 | break; | |
2553 | case SCTP_PARAM_DEL_IP: | |
2554 | sctp_local_bh_disable(); | |
2555 | sctp_write_lock(&asoc->base.addr_lock); | |
2556 | retval = sctp_del_bind_addr(bp, &addr); | |
2557 | sctp_write_unlock(&asoc->base.addr_lock); | |
2558 | sctp_local_bh_enable(); | |
2559 | list_for_each(pos, &asoc->peer.transport_addr_list) { | |
2560 | transport = list_entry(pos, struct sctp_transport, | |
2561 | transports); | |
2562 | sctp_transport_route(transport, NULL, | |
2563 | sctp_sk(asoc->base.sk)); | |
2564 | } | |
2565 | break; | |
2566 | default: | |
2567 | break; | |
2568 | } | |
2569 | ||
2570 | return retval; | |
2571 | } | |
2572 | ||
2573 | /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk | |
2574 | * for the given asconf parameter. If there is no response for this parameter, | |
2575 | * return the error code based on the third argument 'no_err'. | |
2576 | * ADDIP 4.1 | |
2577 | * A7) If an error response is received for a TLV parameter, all TLVs with no | |
2578 | * response before the failed TLV are considered successful if not reported. | |
2579 | * All TLVs after the failed response are considered unsuccessful unless a | |
2580 | * specific success indication is present for the parameter. | |
2581 | */ | |
2582 | static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack, | |
2583 | sctp_addip_param_t *asconf_param, | |
2584 | int no_err) | |
2585 | { | |
2586 | sctp_addip_param_t *asconf_ack_param; | |
2587 | sctp_errhdr_t *err_param; | |
2588 | int length; | |
2589 | int asconf_ack_len = asconf_ack->skb->len; | |
2590 | __u16 err_code; | |
2591 | ||
2592 | if (no_err) | |
2593 | err_code = SCTP_ERROR_NO_ERROR; | |
2594 | else | |
2595 | err_code = SCTP_ERROR_REQ_REFUSED; | |
2596 | ||
2597 | /* Skip the addiphdr from the asconf_ack chunk and store a pointer to | |
2598 | * the first asconf_ack parameter. | |
2599 | */ | |
2600 | length = sizeof(sctp_addiphdr_t); | |
2601 | asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data + | |
2602 | length); | |
2603 | asconf_ack_len -= length; | |
2604 | ||
2605 | while (asconf_ack_len > 0) { | |
2606 | if (asconf_ack_param->crr_id == asconf_param->crr_id) { | |
2607 | switch(asconf_ack_param->param_hdr.type) { | |
2608 | case SCTP_PARAM_SUCCESS_REPORT: | |
2609 | return SCTP_ERROR_NO_ERROR; | |
2610 | case SCTP_PARAM_ERR_CAUSE: | |
2611 | length = sizeof(sctp_addip_param_t); | |
2612 | err_param = (sctp_errhdr_t *) | |
2613 | ((void *)asconf_ack_param + length); | |
2614 | asconf_ack_len -= length; | |
2615 | if (asconf_ack_len > 0) | |
2616 | return err_param->cause; | |
2617 | else | |
2618 | return SCTP_ERROR_INV_PARAM; | |
2619 | break; | |
2620 | default: | |
2621 | return SCTP_ERROR_INV_PARAM; | |
2622 | } | |
2623 | } | |
2624 | ||
2625 | length = ntohs(asconf_ack_param->param_hdr.length); | |
2626 | asconf_ack_param = (sctp_addip_param_t *) | |
2627 | ((void *)asconf_ack_param + length); | |
2628 | asconf_ack_len -= length; | |
2629 | } | |
2630 | ||
2631 | return err_code; | |
2632 | } | |
2633 | ||
2634 | /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */ | |
2635 | int sctp_process_asconf_ack(struct sctp_association *asoc, | |
2636 | struct sctp_chunk *asconf_ack) | |
2637 | { | |
2638 | struct sctp_chunk *asconf = asoc->addip_last_asconf; | |
2639 | union sctp_addr_param *addr_param; | |
2640 | sctp_addip_param_t *asconf_param; | |
2641 | int length = 0; | |
2642 | int asconf_len = asconf->skb->len; | |
2643 | int all_param_pass = 0; | |
2644 | int no_err = 1; | |
2645 | int retval = 0; | |
2646 | __u16 err_code = SCTP_ERROR_NO_ERROR; | |
2647 | ||
2648 | /* Skip the chunkhdr and addiphdr from the last asconf sent and store | |
2649 | * a pointer to address parameter. | |
2650 | */ | |
2651 | length = sizeof(sctp_addip_chunk_t); | |
2652 | addr_param = (union sctp_addr_param *)(asconf->skb->data + length); | |
2653 | asconf_len -= length; | |
2654 | ||
2655 | /* Skip the address parameter in the last asconf sent and store a | |
2656 | * pointer to the first asconf paramter. | |
2657 | */ | |
2658 | length = ntohs(addr_param->v4.param_hdr.length); | |
2659 | asconf_param = (sctp_addip_param_t *)((void *)addr_param + length); | |
2660 | asconf_len -= length; | |
2661 | ||
2662 | /* ADDIP 4.1 | |
2663 | * A8) If there is no response(s) to specific TLV parameter(s), and no | |
2664 | * failures are indicated, then all request(s) are considered | |
2665 | * successful. | |
2666 | */ | |
2667 | if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t)) | |
2668 | all_param_pass = 1; | |
2669 | ||
2670 | /* Process the TLVs contained in the last sent ASCONF chunk. */ | |
2671 | while (asconf_len > 0) { | |
2672 | if (all_param_pass) | |
2673 | err_code = SCTP_ERROR_NO_ERROR; | |
2674 | else { | |
2675 | err_code = sctp_get_asconf_response(asconf_ack, | |
2676 | asconf_param, | |
2677 | no_err); | |
2678 | if (no_err && (SCTP_ERROR_NO_ERROR != err_code)) | |
2679 | no_err = 0; | |
2680 | } | |
2681 | ||
2682 | switch (err_code) { | |
2683 | case SCTP_ERROR_NO_ERROR: | |
2684 | retval = sctp_asconf_param_success(asoc, asconf_param); | |
2685 | break; | |
2686 | ||
2687 | case SCTP_ERROR_RSRC_LOW: | |
2688 | retval = 1; | |
2689 | break; | |
2690 | ||
2691 | case SCTP_ERROR_INV_PARAM: | |
2692 | /* Disable sending this type of asconf parameter in | |
2693 | * future. | |
2694 | */ | |
2695 | asoc->peer.addip_disabled_mask |= | |
2696 | asconf_param->param_hdr.type; | |
2697 | break; | |
2698 | ||
2699 | case SCTP_ERROR_REQ_REFUSED: | |
2700 | case SCTP_ERROR_DEL_LAST_IP: | |
2701 | case SCTP_ERROR_DEL_SRC_IP: | |
2702 | default: | |
2703 | break; | |
2704 | } | |
2705 | ||
2706 | /* Skip the processed asconf parameter and move to the next | |
2707 | * one. | |
2708 | */ | |
2709 | length = ntohs(asconf_param->param_hdr.length); | |
2710 | asconf_param = (sctp_addip_param_t *)((void *)asconf_param + | |
2711 | length); | |
2712 | asconf_len -= length; | |
2713 | } | |
2714 | ||
2715 | /* Free the cached last sent asconf chunk. */ | |
2716 | sctp_chunk_free(asconf); | |
2717 | asoc->addip_last_asconf = NULL; | |
2718 | ||
2719 | /* Send the next asconf chunk from the addip chunk queue. */ | |
2720 | asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks); | |
2721 | if (asconf) { | |
2722 | /* Hold the chunk until an ASCONF_ACK is received. */ | |
2723 | sctp_chunk_hold(asconf); | |
2724 | if (sctp_primitive_ASCONF(asoc, asconf)) | |
2725 | sctp_chunk_free(asconf); | |
2726 | else | |
2727 | asoc->addip_last_asconf = asconf; | |
2728 | } | |
2729 | ||
2730 | return retval; | |
2731 | } | |
2732 | ||
2733 | /* Make a FWD TSN chunk. */ | |
2734 | struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc, | |
2735 | __u32 new_cum_tsn, size_t nstreams, | |
2736 | struct sctp_fwdtsn_skip *skiplist) | |
2737 | { | |
2738 | struct sctp_chunk *retval = NULL; | |
2739 | struct sctp_fwdtsn_chunk *ftsn_chunk; | |
2740 | struct sctp_fwdtsn_hdr ftsn_hdr; | |
2741 | struct sctp_fwdtsn_skip skip; | |
2742 | size_t hint; | |
2743 | int i; | |
2744 | ||
2745 | hint = (nstreams + 1) * sizeof(__u32); | |
2746 | ||
2747 | /* Maybe set the T-bit if we have no association. */ | |
2748 | retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint); | |
2749 | ||
2750 | if (!retval) | |
2751 | return NULL; | |
2752 | ||
2753 | ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr; | |
2754 | ||
2755 | ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn); | |
2756 | retval->subh.fwdtsn_hdr = | |
2757 | sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr); | |
2758 | ||
2759 | for (i = 0; i < nstreams; i++) { | |
2760 | skip.stream = skiplist[i].stream; | |
2761 | skip.ssn = skiplist[i].ssn; | |
2762 | sctp_addto_chunk(retval, sizeof(skip), &skip); | |
2763 | } | |
2764 | ||
2765 | return retval; | |
2766 | } |