Commit | Line | Data |
---|---|---|
47505b8b | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
60c778b2 | 2 | /* SCTP kernel implementation |
1da177e4 LT |
3 | * (C) Copyright IBM Corp. 2003, 2004 |
4 | * | |
60c778b2 | 5 | * This file is part of the SCTP kernel implementation |
1da177e4 | 6 | * |
59c51591 | 7 | * This file contains the code relating the chunk abstraction. |
1da177e4 | 8 | * |
1da177e4 LT |
9 | * Please send any bug reports or fixes you make to the |
10 | * email address(es): | |
91705c61 | 11 | * lksctp developers <linux-sctp@vger.kernel.org> |
1da177e4 | 12 | * |
1da177e4 LT |
13 | * Written or modified by: |
14 | * Jon Grimm <jgrimm@us.ibm.com> | |
15 | * Sridhar Samudrala <sri@us.ibm.com> | |
1da177e4 LT |
16 | */ |
17 | ||
145ce502 JP |
18 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
19 | ||
1da177e4 LT |
20 | #include <linux/types.h> |
21 | #include <linux/kernel.h> | |
22 | #include <linux/net.h> | |
23 | #include <linux/inet.h> | |
24 | #include <linux/skbuff.h> | |
5a0e3ad6 | 25 | #include <linux/slab.h> |
1da177e4 LT |
26 | #include <net/sock.h> |
27 | #include <net/sctp/sctp.h> | |
28 | #include <net/sctp/sm.h> | |
29 | ||
30 | /* This file is mostly in anticipation of future work, but initially | |
31 | * populate with fragment tracking for an outbound message. | |
32 | */ | |
33 | ||
34 | /* Initialize datamsg from memory. */ | |
35 | static void sctp_datamsg_init(struct sctp_datamsg *msg) | |
36 | { | |
c0acdfb4 | 37 | refcount_set(&msg->refcnt, 1); |
1da177e4 LT |
38 | msg->send_failed = 0; |
39 | msg->send_error = 0; | |
0e3aef8d | 40 | msg->can_delay = 1; |
e5f61296 | 41 | msg->abandoned = 0; |
1da177e4 LT |
42 | msg->expires_at = 0; |
43 | INIT_LIST_HEAD(&msg->chunks); | |
44 | } | |
45 | ||
46 | /* Allocate and initialize datamsg. */ | |
dda91928 | 47 | static struct sctp_datamsg *sctp_datamsg_new(gfp_t gfp) |
1da177e4 LT |
48 | { |
49 | struct sctp_datamsg *msg; | |
50 | msg = kmalloc(sizeof(struct sctp_datamsg), gfp); | |
e8c38751 | 51 | if (msg) { |
1da177e4 | 52 | sctp_datamsg_init(msg); |
e8c38751 LZ |
53 | SCTP_DBG_OBJCNT_INC(datamsg); |
54 | } | |
1da177e4 LT |
55 | return msg; |
56 | } | |
57 | ||
b61c654f XL |
58 | void sctp_datamsg_free(struct sctp_datamsg *msg) |
59 | { | |
60 | struct sctp_chunk *chunk; | |
61 | ||
62 | /* This doesn't have to be a _safe vairant because | |
63 | * sctp_chunk_free() only drops the refs. | |
64 | */ | |
65 | list_for_each_entry(chunk, &msg->chunks, frag_list) | |
66 | sctp_chunk_free(chunk); | |
67 | ||
68 | sctp_datamsg_put(msg); | |
69 | } | |
70 | ||
1da177e4 LT |
71 | /* Final destructruction of datamsg memory. */ |
72 | static void sctp_datamsg_destroy(struct sctp_datamsg *msg) | |
73 | { | |
a1e3a059 | 74 | struct sctp_association *asoc = NULL; |
1da177e4 LT |
75 | struct list_head *pos, *temp; |
76 | struct sctp_chunk *chunk; | |
1da177e4 | 77 | struct sctp_ulpevent *ev; |
b6e6b5f1 | 78 | int error, sent; |
1da177e4 LT |
79 | |
80 | /* Release all references. */ | |
81 | list_for_each_safe(pos, temp, &msg->chunks) { | |
82 | list_del_init(pos); | |
83 | chunk = list_entry(pos, struct sctp_chunk, frag_list); | |
b6e6b5f1 XL |
84 | |
85 | if (!msg->send_failed) { | |
86 | sctp_chunk_put(chunk); | |
87 | continue; | |
1da177e4 LT |
88 | } |
89 | ||
b6e6b5f1 XL |
90 | asoc = chunk->asoc; |
91 | error = msg->send_error ?: asoc->outqueue.error; | |
92 | sent = chunk->has_tsn ? SCTP_DATA_SENT : SCTP_DATA_UNSENT; | |
1da177e4 | 93 | |
b6e6b5f1 XL |
94 | if (sctp_ulpevent_type_enabled(asoc->subscribe, |
95 | SCTP_SEND_FAILED)) { | |
1da177e4 LT |
96 | ev = sctp_ulpevent_make_send_failed(asoc, chunk, sent, |
97 | error, GFP_ATOMIC); | |
98 | if (ev) | |
9162e0ed | 99 | asoc->stream.si->enqueue_event(&asoc->ulpq, ev); |
1da177e4 LT |
100 | } |
101 | ||
b6e6b5f1 XL |
102 | if (sctp_ulpevent_type_enabled(asoc->subscribe, |
103 | SCTP_SEND_FAILED_EVENT)) { | |
104 | ev = sctp_ulpevent_make_send_failed_event(asoc, chunk, | |
105 | sent, error, | |
106 | GFP_ATOMIC); | |
107 | if (ev) | |
108 | asoc->stream.si->enqueue_event(&asoc->ulpq, ev); | |
109 | } | |
110 | ||
1da177e4 LT |
111 | sctp_chunk_put(chunk); |
112 | } | |
113 | ||
114 | SCTP_DBG_OBJCNT_DEC(datamsg); | |
115 | kfree(msg); | |
116 | } | |
117 | ||
118 | /* Hold a reference. */ | |
119 | static void sctp_datamsg_hold(struct sctp_datamsg *msg) | |
120 | { | |
c0acdfb4 | 121 | refcount_inc(&msg->refcnt); |
1da177e4 LT |
122 | } |
123 | ||
124 | /* Release a reference. */ | |
125 | void sctp_datamsg_put(struct sctp_datamsg *msg) | |
126 | { | |
c0acdfb4 | 127 | if (refcount_dec_and_test(&msg->refcnt)) |
1da177e4 LT |
128 | sctp_datamsg_destroy(msg); |
129 | } | |
130 | ||
1da177e4 LT |
131 | /* Assign a chunk to this datamsg. */ |
132 | static void sctp_datamsg_assign(struct sctp_datamsg *msg, struct sctp_chunk *chunk) | |
133 | { | |
134 | sctp_datamsg_hold(msg); | |
135 | chunk->msg = msg; | |
136 | } | |
137 | ||
138 | ||
139 | /* A data chunk can have a maximum payload of (2^16 - 20). Break | |
140 | * down any such message into smaller chunks. Opportunistically, fragment | |
141 | * the chunks down to the current MTU constraints. We may get refragmented | |
142 | * later if the PMTU changes, but it is _much better_ to fragment immediately | |
143 | * with a reasonable guess than always doing our fragmentation on the | |
144 | * soft-interrupt. | |
145 | */ | |
146 | struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc, | |
147 | struct sctp_sndrcvinfo *sinfo, | |
e0eb093e | 148 | struct iov_iter *from) |
1da177e4 | 149 | { |
bfd2e4b8 MRL |
150 | size_t len, first_len, max_data, remaining; |
151 | size_t msg_len = iov_iter_count(from); | |
1b1e0bc9 | 152 | struct sctp_shared_key *shkey = NULL; |
bfd2e4b8 | 153 | struct list_head *pos, *temp; |
1da177e4 LT |
154 | struct sctp_chunk *chunk; |
155 | struct sctp_datamsg *msg; | |
bfd2e4b8 | 156 | int err; |
1da177e4 LT |
157 | |
158 | msg = sctp_datamsg_new(GFP_KERNEL); | |
159 | if (!msg) | |
6e51fe75 | 160 | return ERR_PTR(-ENOMEM); |
1da177e4 LT |
161 | |
162 | /* Note: Calculate this outside of the loop, so that all fragments | |
163 | * have the same expiration. | |
164 | */ | |
8ae808eb XL |
165 | if (asoc->peer.prsctp_capable && sinfo->sinfo_timetolive && |
166 | (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags) || | |
167 | !SCTP_PR_POLICY(sinfo->sinfo_flags))) | |
1da177e4 | 168 | msg->expires_at = jiffies + |
bfd2e4b8 | 169 | msecs_to_jiffies(sinfo->sinfo_timetolive); |
0605483f | 170 | |
3e62abf9 VY |
171 | /* This is the biggest possible DATA chunk that can fit into |
172 | * the packet | |
173 | */ | |
2f5e3c9d | 174 | max_data = asoc->frag_point; |
afd0a800 JA |
175 | if (unlikely(!max_data)) { |
176 | max_data = sctp_min_frag_point(sctp_sk(asoc->base.sk), | |
177 | sctp_datachk_len(&asoc->stream)); | |
ac510505 | 178 | pr_warn_ratelimited("%s: asoc:%p frag_point is zero, forcing max_data to default minimum (%zu)", |
afd0a800 JA |
179 | __func__, asoc, max_data); |
180 | } | |
1da177e4 | 181 | |
9932564f | 182 | /* If the peer requested that we authenticate DATA chunks |
2bccbadf | 183 | * we need to account for bundling of the AUTH chunks along with |
4cd57c80 VY |
184 | * DATA. |
185 | */ | |
186 | if (sctp_auth_send_cid(SCTP_CID_DATA, asoc)) { | |
187 | struct sctp_hmac *hmac_desc = sctp_auth_asoc_get_hmac(asoc); | |
188 | ||
189 | if (hmac_desc) | |
bb96dec7 | 190 | max_data -= SCTP_PAD4(sizeof(struct sctp_auth_chunk) + |
e2f036a9 | 191 | hmac_desc->hmac_len); |
1b1e0bc9 | 192 | |
3ff547c0 XL |
193 | if (sinfo->sinfo_tsn && |
194 | sinfo->sinfo_ssn != asoc->active_key_id) { | |
195 | shkey = sctp_auth_get_shkey(asoc, sinfo->sinfo_ssn); | |
196 | if (!shkey) { | |
197 | err = -EINVAL; | |
198 | goto errout; | |
199 | } | |
200 | } else { | |
201 | shkey = asoc->shkey; | |
202 | } | |
4cd57c80 VY |
203 | } |
204 | ||
bfd2e4b8 MRL |
205 | /* Set first_len and then account for possible bundles on first frag */ |
206 | first_len = max_data; | |
1da177e4 | 207 | |
5d7ff261 VY |
208 | /* Check to see if we have a pending SACK and try to let it be bundled |
209 | * with this message. Do this if we don't have any data queued already. | |
210 | * To check that, look at out_qlen and retransmit list. | |
211 | * NOTE: we will not reduce to account for SACK, if the message would | |
212 | * not have been fragmented. | |
213 | */ | |
214 | if (timer_pending(&asoc->timers[SCTP_EVENT_TIMEOUT_SACK]) && | |
215 | asoc->outqueue.out_qlen == 0 && | |
216 | list_empty(&asoc->outqueue.retransmit) && | |
bfd2e4b8 | 217 | msg_len > max_data) |
d4d6c614 | 218 | first_len -= SCTP_PAD4(sizeof(struct sctp_sack_chunk)); |
5d7ff261 | 219 | |
1da177e4 | 220 | /* Encourage Cookie-ECHO bundling. */ |
5d7ff261 | 221 | if (asoc->state < SCTP_STATE_COOKIE_ECHOED) |
bfd2e4b8 | 222 | first_len -= SCTP_ARBITRARY_COOKIE_ECHO_LEN; |
3e62abf9 VY |
223 | |
224 | /* Account for a different sized first fragment */ | |
225 | if (msg_len >= first_len) { | |
0e3aef8d | 226 | msg->can_delay = 0; |
fedb1bd3 | 227 | if (msg_len > first_len) |
4e7696d9 | 228 | SCTP_INC_STATS(asoc->base.net, |
fedb1bd3 | 229 | SCTP_MIB_FRAGUSRMSGS); |
bfd2e4b8 MRL |
230 | } else { |
231 | /* Which may be the only one... */ | |
232 | first_len = msg_len; | |
233 | } | |
1da177e4 | 234 | |
bfd2e4b8 MRL |
235 | /* Create chunks for all DATA chunks. */ |
236 | for (remaining = msg_len; remaining; remaining -= len) { | |
237 | u8 frag = SCTP_DATA_MIDDLE_FRAG; | |
1da177e4 | 238 | |
bfd2e4b8 MRL |
239 | if (remaining == msg_len) { |
240 | /* First frag, which may also be the last */ | |
1da177e4 | 241 | frag |= SCTP_DATA_FIRST_FRAG; |
bfd2e4b8 MRL |
242 | len = first_len; |
243 | } else { | |
244 | /* Middle frags */ | |
245 | len = max_data; | |
246 | } | |
1da177e4 | 247 | |
bfd2e4b8 MRL |
248 | if (len >= remaining) { |
249 | /* Last frag, which may also be the first */ | |
250 | len = remaining; | |
1da177e4 LT |
251 | frag |= SCTP_DATA_LAST_FRAG; |
252 | ||
b93d6471 WY |
253 | /* The application requests to set the I-bit of the |
254 | * last DATA chunk of a user message when providing | |
255 | * the user message to the SCTP implementation. | |
256 | */ | |
257 | if ((sinfo->sinfo_flags & SCTP_EOF) || | |
258 | (sinfo->sinfo_flags & SCTP_SACK_IMMEDIATELY)) | |
259 | frag |= SCTP_DATA_SACK_IMM; | |
260 | } | |
261 | ||
0c3f6f65 XL |
262 | chunk = asoc->stream.si->make_datafrag(asoc, sinfo, len, frag, |
263 | GFP_KERNEL); | |
6e51fe75 TR |
264 | if (!chunk) { |
265 | err = -ENOMEM; | |
1da177e4 | 266 | goto errout; |
6e51fe75 TR |
267 | } |
268 | ||
e0eb093e | 269 | err = sctp_user_addto_chunk(chunk, len, from); |
1da177e4 | 270 | if (err < 0) |
be364c8c | 271 | goto errout_chunk_free; |
1da177e4 | 272 | |
1b1e0bc9 XL |
273 | chunk->shkey = shkey; |
274 | ||
1da177e4 | 275 | /* Put the chunk->skb back into the form expected by send. */ |
bfd2e4b8 MRL |
276 | __skb_pull(chunk->skb, (__u8 *)chunk->chunk_hdr - |
277 | chunk->skb->data); | |
1da177e4 LT |
278 | |
279 | sctp_datamsg_assign(msg, chunk); | |
280 | list_add_tail(&chunk->frag_list, &msg->chunks); | |
281 | } | |
282 | ||
283 | return msg; | |
284 | ||
be364c8c TR |
285 | errout_chunk_free: |
286 | sctp_chunk_free(chunk); | |
287 | ||
1da177e4 LT |
288 | errout: |
289 | list_for_each_safe(pos, temp, &msg->chunks) { | |
290 | list_del_init(pos); | |
291 | chunk = list_entry(pos, struct sctp_chunk, frag_list); | |
292 | sctp_chunk_free(chunk); | |
293 | } | |
80445cfb | 294 | sctp_datamsg_put(msg); |
bfd2e4b8 | 295 | |
6e51fe75 | 296 | return ERR_PTR(err); |
1da177e4 LT |
297 | } |
298 | ||
299 | /* Check whether this message has expired. */ | |
300 | int sctp_chunk_abandoned(struct sctp_chunk *chunk) | |
301 | { | |
8ae808eb | 302 | if (!chunk->asoc->peer.prsctp_capable) |
1da177e4 LT |
303 | return 0; |
304 | ||
e5f61296 XL |
305 | if (chunk->msg->abandoned) |
306 | return 1; | |
307 | ||
779edd73 XL |
308 | if (!chunk->has_tsn && |
309 | !(chunk->chunk_hdr->flags & SCTP_DATA_FIRST_FRAG)) | |
310 | return 0; | |
311 | ||
a6c2f792 | 312 | if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) && |
0605483f | 313 | time_after(jiffies, chunk->msg->expires_at)) { |
d229d48d | 314 | struct sctp_stream_out *streamout = |
05364ca0 KK |
315 | SCTP_SO(&chunk->asoc->stream, |
316 | chunk->sinfo.sinfo_stream); | |
d229d48d XL |
317 | |
318 | if (chunk->sent_count) { | |
a6c2f792 | 319 | chunk->asoc->abandoned_sent[SCTP_PR_INDEX(TTL)]++; |
f952be79 | 320 | streamout->ext->abandoned_sent[SCTP_PR_INDEX(TTL)]++; |
d229d48d | 321 | } else { |
a6c2f792 | 322 | chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++; |
f952be79 | 323 | streamout->ext->abandoned_unsent[SCTP_PR_INDEX(TTL)]++; |
d229d48d | 324 | } |
e5f61296 | 325 | chunk->msg->abandoned = 1; |
1da177e4 | 326 | return 1; |
01aadb3a | 327 | } else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) && |
0605483f | 328 | chunk->sent_count > chunk->sinfo.sinfo_timetolive) { |
d229d48d | 329 | struct sctp_stream_out *streamout = |
05364ca0 KK |
330 | SCTP_SO(&chunk->asoc->stream, |
331 | chunk->sinfo.sinfo_stream); | |
d229d48d | 332 | |
01aadb3a | 333 | chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++; |
f952be79 | 334 | streamout->ext->abandoned_sent[SCTP_PR_INDEX(RTX)]++; |
e5f61296 | 335 | chunk->msg->abandoned = 1; |
01aadb3a | 336 | return 1; |
8ae808eb XL |
337 | } else if (!SCTP_PR_POLICY(chunk->sinfo.sinfo_flags) && |
338 | chunk->msg->expires_at && | |
339 | time_after(jiffies, chunk->msg->expires_at)) { | |
e5f61296 | 340 | chunk->msg->abandoned = 1; |
8ae808eb | 341 | return 1; |
a6c2f792 | 342 | } |
8dbdf1f5 | 343 | /* PRIO policy is processed by sendmsg, not here */ |
1da177e4 LT |
344 | |
345 | return 0; | |
346 | } | |
347 | ||
348 | /* This chunk (and consequently entire message) has failed in its sending. */ | |
349 | void sctp_chunk_fail(struct sctp_chunk *chunk, int error) | |
350 | { | |
351 | chunk->msg->send_failed = 1; | |
352 | chunk->msg->send_error = error; | |
353 | } |