Commit | Line | Data |
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60c778b2 | 1 | /* SCTP kernel implementation |
1da177e4 LT |
2 | * (C) Copyright IBM Corp. 2001, 2004 |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001-2002 Intel Corp. | |
6 | * Copyright (c) 2002 Nokia Corp. | |
7 | * | |
60c778b2 | 8 | * This is part of the SCTP Linux Kernel Implementation. |
1da177e4 LT |
9 | * |
10 | * These are the state functions for the state machine. | |
11 | * | |
60c778b2 | 12 | * This SCTP implementation is free software; |
1da177e4 LT |
13 | * you can redistribute it and/or modify it under the terms of |
14 | * the GNU General Public License as published by | |
15 | * the Free Software Foundation; either version 2, or (at your option) | |
16 | * any later version. | |
17 | * | |
60c778b2 | 18 | * This SCTP implementation is distributed in the hope that it |
1da177e4 LT |
19 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
20 | * ************************ | |
21 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
22 | * See the GNU General Public License for more details. | |
23 | * | |
24 | * You should have received a copy of the GNU General Public License | |
25 | * along with GNU CC; see the file COPYING. If not, write to | |
26 | * the Free Software Foundation, 59 Temple Place - Suite 330, | |
27 | * Boston, MA 02111-1307, USA. | |
28 | * | |
29 | * Please send any bug reports or fixes you make to the | |
30 | * email address(es): | |
31 | * lksctp developers <lksctp-developers@lists.sourceforge.net> | |
32 | * | |
33 | * Or submit a bug report through the following website: | |
34 | * http://www.sf.net/projects/lksctp | |
35 | * | |
36 | * Written or modified by: | |
37 | * La Monte H.P. Yarroll <piggy@acm.org> | |
38 | * Karl Knutson <karl@athena.chicago.il.us> | |
39 | * Mathew Kotowsky <kotowsky@sctp.org> | |
40 | * Sridhar Samudrala <samudrala@us.ibm.com> | |
41 | * Jon Grimm <jgrimm@us.ibm.com> | |
42 | * Hui Huang <hui.huang@nokia.com> | |
43 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
44 | * Daisy Chang <daisyc@us.ibm.com> | |
45 | * Ardelle Fan <ardelle.fan@intel.com> | |
46 | * Ryan Layer <rmlayer@us.ibm.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 <net/sock.h> | |
60 | #include <net/inet_ecn.h> | |
61 | #include <linux/skbuff.h> | |
62 | #include <net/sctp/sctp.h> | |
63 | #include <net/sctp/sm.h> | |
64 | #include <net/sctp/structs.h> | |
65 | ||
66 | static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep, | |
67 | const struct sctp_association *asoc, | |
68 | struct sctp_chunk *chunk, | |
69 | const void *payload, | |
70 | size_t paylen); | |
71 | static int sctp_eat_data(const struct sctp_association *asoc, | |
72 | struct sctp_chunk *chunk, | |
73 | sctp_cmd_seq_t *commands); | |
74 | static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc, | |
75 | const struct sctp_chunk *chunk); | |
76 | static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep, | |
77 | const struct sctp_association *asoc, | |
78 | const struct sctp_chunk *chunk, | |
79 | sctp_cmd_seq_t *commands, | |
80 | struct sctp_chunk *err_chunk); | |
81 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, | |
82 | const struct sctp_association *asoc, | |
83 | const sctp_subtype_t type, | |
84 | void *arg, | |
85 | sctp_cmd_seq_t *commands); | |
86 | static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, | |
87 | const struct sctp_association *asoc, | |
88 | const sctp_subtype_t type, | |
89 | void *arg, | |
90 | sctp_cmd_seq_t *commands); | |
ece25dfa VY |
91 | static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, |
92 | const struct sctp_association *asoc, | |
93 | const sctp_subtype_t type, | |
94 | void *arg, | |
95 | sctp_cmd_seq_t *commands); | |
1da177e4 LT |
96 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk); |
97 | ||
52c1da39 | 98 | static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, |
f94c0198 | 99 | __be16 error, int sk_err, |
52c1da39 AB |
100 | const struct sctp_association *asoc, |
101 | struct sctp_transport *transport); | |
102 | ||
aecedeab | 103 | static sctp_disposition_t sctp_sf_abort_violation( |
ece25dfa | 104 | const struct sctp_endpoint *ep, |
aecedeab WY |
105 | const struct sctp_association *asoc, |
106 | void *arg, | |
107 | sctp_cmd_seq_t *commands, | |
108 | const __u8 *payload, | |
109 | const size_t paylen); | |
110 | ||
52c1da39 AB |
111 | static sctp_disposition_t sctp_sf_violation_chunklen( |
112 | const struct sctp_endpoint *ep, | |
113 | const struct sctp_association *asoc, | |
114 | const sctp_subtype_t type, | |
115 | void *arg, | |
116 | sctp_cmd_seq_t *commands); | |
1da177e4 | 117 | |
6f4c618d WY |
118 | static sctp_disposition_t sctp_sf_violation_paramlen( |
119 | const struct sctp_endpoint *ep, | |
120 | const struct sctp_association *asoc, | |
121 | const sctp_subtype_t type, | |
ba016670 | 122 | void *arg, void *ext, |
6f4c618d WY |
123 | sctp_cmd_seq_t *commands); |
124 | ||
aecedeab WY |
125 | static sctp_disposition_t sctp_sf_violation_ctsn( |
126 | const struct sctp_endpoint *ep, | |
127 | const struct sctp_association *asoc, | |
128 | const sctp_subtype_t type, | |
129 | void *arg, | |
130 | sctp_cmd_seq_t *commands); | |
131 | ||
ece25dfa VY |
132 | static sctp_disposition_t sctp_sf_violation_chunk( |
133 | const struct sctp_endpoint *ep, | |
134 | const struct sctp_association *asoc, | |
135 | const sctp_subtype_t type, | |
136 | void *arg, | |
137 | sctp_cmd_seq_t *commands); | |
138 | ||
bbd0d598 VY |
139 | static sctp_ierror_t sctp_sf_authenticate(const struct sctp_endpoint *ep, |
140 | const struct sctp_association *asoc, | |
141 | const sctp_subtype_t type, | |
142 | struct sctp_chunk *chunk); | |
143 | ||
75205f47 VY |
144 | static sctp_disposition_t __sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, |
145 | const struct sctp_association *asoc, | |
146 | const sctp_subtype_t type, | |
147 | void *arg, | |
148 | sctp_cmd_seq_t *commands); | |
149 | ||
1da177e4 LT |
150 | /* Small helper function that checks if the chunk length |
151 | * is of the appropriate length. The 'required_length' argument | |
152 | * is set to be the size of a specific chunk we are testing. | |
153 | * Return Values: 1 = Valid length | |
154 | * 0 = Invalid length | |
155 | * | |
156 | */ | |
157 | static inline int | |
158 | sctp_chunk_length_valid(struct sctp_chunk *chunk, | |
159 | __u16 required_length) | |
160 | { | |
161 | __u16 chunk_length = ntohs(chunk->chunk_hdr->length); | |
162 | ||
163 | if (unlikely(chunk_length < required_length)) | |
164 | return 0; | |
165 | ||
166 | return 1; | |
167 | } | |
168 | ||
169 | /********************************************************** | |
170 | * These are the state functions for handling chunk events. | |
171 | **********************************************************/ | |
172 | ||
173 | /* | |
174 | * Process the final SHUTDOWN COMPLETE. | |
175 | * | |
176 | * Section: 4 (C) (diagram), 9.2 | |
177 | * Upon reception of the SHUTDOWN COMPLETE chunk the endpoint will verify | |
178 | * that it is in SHUTDOWN-ACK-SENT state, if it is not the chunk should be | |
179 | * discarded. If the endpoint is in the SHUTDOWN-ACK-SENT state the endpoint | |
180 | * should stop the T2-shutdown timer and remove all knowledge of the | |
181 | * association (and thus the association enters the CLOSED state). | |
182 | * | |
047a2428 | 183 | * Verification Tag: 8.5.1(C), sctpimpguide 2.41. |
1da177e4 LT |
184 | * C) Rules for packet carrying SHUTDOWN COMPLETE: |
185 | * ... | |
047a2428 JF |
186 | * - The receiver of a SHUTDOWN COMPLETE shall accept the packet |
187 | * if the Verification Tag field of the packet matches its own tag and | |
188 | * the T bit is not set | |
189 | * OR | |
190 | * it is set to its peer's tag and the T bit is set in the Chunk | |
191 | * Flags. | |
192 | * Otherwise, the receiver MUST silently discard the packet | |
193 | * and take no further action. An endpoint MUST ignore the | |
194 | * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state. | |
1da177e4 LT |
195 | * |
196 | * Inputs | |
197 | * (endpoint, asoc, chunk) | |
198 | * | |
199 | * Outputs | |
200 | * (asoc, reply_msg, msg_up, timers, counters) | |
201 | * | |
202 | * The return value is the disposition of the chunk. | |
203 | */ | |
204 | sctp_disposition_t sctp_sf_do_4_C(const struct sctp_endpoint *ep, | |
205 | const struct sctp_association *asoc, | |
206 | const sctp_subtype_t type, | |
207 | void *arg, | |
208 | sctp_cmd_seq_t *commands) | |
209 | { | |
210 | struct sctp_chunk *chunk = arg; | |
211 | struct sctp_ulpevent *ev; | |
212 | ||
ece25dfa VY |
213 | if (!sctp_vtag_verify_either(chunk, asoc)) |
214 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
215 | ||
1da177e4 LT |
216 | /* RFC 2960 6.10 Bundling |
217 | * | |
218 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
219 | * SHUTDOWN COMPLETE with any other chunks. | |
220 | */ | |
221 | if (!chunk->singleton) | |
ece25dfa | 222 | return sctp_sf_violation_chunk(ep, asoc, type, arg, commands); |
1da177e4 | 223 | |
ece25dfa VY |
224 | /* Make sure that the SHUTDOWN_COMPLETE chunk has a valid length. */ |
225 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
226 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
227 | commands); | |
1da177e4 LT |
228 | |
229 | /* RFC 2960 10.2 SCTP-to-ULP | |
230 | * | |
231 | * H) SHUTDOWN COMPLETE notification | |
232 | * | |
233 | * When SCTP completes the shutdown procedures (section 9.2) this | |
234 | * notification is passed to the upper layer. | |
235 | */ | |
236 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 237 | 0, 0, 0, NULL, GFP_ATOMIC); |
df7deeb5 VY |
238 | if (ev) |
239 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
d808ad9a | 240 | SCTP_ULPEVENT(ev)); |
1da177e4 LT |
241 | |
242 | /* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint | |
243 | * will verify that it is in SHUTDOWN-ACK-SENT state, if it is | |
244 | * not the chunk should be discarded. If the endpoint is in | |
245 | * the SHUTDOWN-ACK-SENT state the endpoint should stop the | |
246 | * T2-shutdown timer and remove all knowledge of the | |
247 | * association (and thus the association enters the CLOSED | |
248 | * state). | |
249 | */ | |
250 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
251 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
252 | ||
253 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
254 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
255 | ||
256 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
257 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
258 | ||
259 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
260 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
261 | ||
262 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
263 | ||
264 | return SCTP_DISPOSITION_DELETE_TCB; | |
1da177e4 LT |
265 | } |
266 | ||
267 | /* | |
268 | * Respond to a normal INIT chunk. | |
269 | * We are the side that is being asked for an association. | |
270 | * | |
271 | * Section: 5.1 Normal Establishment of an Association, B | |
272 | * B) "Z" shall respond immediately with an INIT ACK chunk. The | |
273 | * destination IP address of the INIT ACK MUST be set to the source | |
274 | * IP address of the INIT to which this INIT ACK is responding. In | |
275 | * the response, besides filling in other parameters, "Z" must set the | |
276 | * Verification Tag field to Tag_A, and also provide its own | |
277 | * Verification Tag (Tag_Z) in the Initiate Tag field. | |
278 | * | |
d808ad9a | 279 | * Verification Tag: Must be 0. |
1da177e4 LT |
280 | * |
281 | * Inputs | |
282 | * (endpoint, asoc, chunk) | |
283 | * | |
284 | * Outputs | |
285 | * (asoc, reply_msg, msg_up, timers, counters) | |
286 | * | |
287 | * The return value is the disposition of the chunk. | |
288 | */ | |
289 | sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep, | |
290 | const struct sctp_association *asoc, | |
291 | const sctp_subtype_t type, | |
292 | void *arg, | |
293 | sctp_cmd_seq_t *commands) | |
294 | { | |
295 | struct sctp_chunk *chunk = arg; | |
296 | struct sctp_chunk *repl; | |
297 | struct sctp_association *new_asoc; | |
298 | struct sctp_chunk *err_chunk; | |
299 | struct sctp_packet *packet; | |
300 | sctp_unrecognized_param_t *unk_param; | |
1da177e4 LT |
301 | int len; |
302 | ||
303 | /* 6.10 Bundling | |
304 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
305 | * SHUTDOWN COMPLETE with any other chunks. | |
d808ad9a | 306 | * |
1da177e4 LT |
307 | * IG Section 2.11.2 |
308 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
309 | * enforce these rules by silently discarding an arriving packet | |
310 | * with an INIT chunk that is bundled with other chunks. | |
311 | */ | |
312 | if (!chunk->singleton) | |
313 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
314 | ||
315 | /* If the packet is an OOTB packet which is temporarily on the | |
316 | * control endpoint, respond with an ABORT. | |
317 | */ | |
8190f89d WY |
318 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) { |
319 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
1da177e4 | 320 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
8190f89d | 321 | } |
1da177e4 | 322 | |
1da177e4 | 323 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification |
d808ad9a | 324 | * Tag. |
1da177e4 LT |
325 | */ |
326 | if (chunk->sctp_hdr->vtag != 0) | |
327 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
328 | ||
329 | /* Make sure that the INIT chunk has a valid length. | |
330 | * Normally, this would cause an ABORT with a Protocol Violation | |
331 | * error, but since we don't have an association, we'll | |
332 | * just discard the packet. | |
333 | */ | |
334 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
335 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
336 | ||
bec9640b VY |
337 | /* If the INIT is coming toward a closing socket, we'll send back |
338 | * and ABORT. Essentially, this catches the race of INIT being | |
339 | * backloged to the socket at the same time as the user isses close(). | |
340 | * Since the socket and all its associations are going away, we | |
341 | * can treat this OOTB | |
342 | */ | |
343 | if (sctp_sstate(ep->base.sk, CLOSING)) | |
344 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
345 | ||
1da177e4 LT |
346 | /* Verify the INIT chunk before processing it. */ |
347 | err_chunk = NULL; | |
348 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
349 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
350 | &err_chunk)) { | |
351 | /* This chunk contains fatal error. It is to be discarded. | |
352 | * Send an ABORT, with causes if there is any. | |
353 | */ | |
354 | if (err_chunk) { | |
355 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
356 | (__u8 *)(err_chunk->chunk_hdr) + | |
357 | sizeof(sctp_chunkhdr_t), | |
358 | ntohs(err_chunk->chunk_hdr->length) - | |
359 | sizeof(sctp_chunkhdr_t)); | |
360 | ||
361 | sctp_chunk_free(err_chunk); | |
362 | ||
363 | if (packet) { | |
364 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
365 | SCTP_PACKET(packet)); | |
366 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
367 | return SCTP_DISPOSITION_CONSUME; | |
368 | } else { | |
369 | return SCTP_DISPOSITION_NOMEM; | |
370 | } | |
371 | } else { | |
372 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
373 | commands); | |
374 | } | |
375 | } | |
376 | ||
d808ad9a | 377 | /* Grab the INIT header. */ |
1da177e4 LT |
378 | chunk->subh.init_hdr = (sctp_inithdr_t *)chunk->skb->data; |
379 | ||
380 | /* Tag the variable length parameters. */ | |
381 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
382 | ||
383 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
384 | if (!new_asoc) | |
385 | goto nomem; | |
386 | ||
409b95af VY |
387 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
388 | sctp_scope(sctp_source(chunk)), | |
389 | GFP_ATOMIC) < 0) | |
390 | goto nomem_init; | |
391 | ||
1da177e4 LT |
392 | /* The call, sctp_process_init(), can fail on memory allocation. */ |
393 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
394 | sctp_source(chunk), | |
395 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
396 | GFP_ATOMIC)) | |
397 | goto nomem_init; | |
398 | ||
1da177e4 LT |
399 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ |
400 | ||
401 | /* If there are errors need to be reported for unknown parameters, | |
402 | * make sure to reserve enough room in the INIT ACK for them. | |
403 | */ | |
404 | len = 0; | |
405 | if (err_chunk) | |
406 | len = ntohs(err_chunk->chunk_hdr->length) - | |
407 | sizeof(sctp_chunkhdr_t); | |
408 | ||
1da177e4 LT |
409 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
410 | if (!repl) | |
df7deeb5 | 411 | goto nomem_init; |
1da177e4 LT |
412 | |
413 | /* If there are errors need to be reported for unknown parameters, | |
414 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
415 | * parameter. | |
416 | */ | |
417 | if (err_chunk) { | |
418 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
419 | * ERROR chunk generated by sctp_verify_init(). Since the | |
420 | * error cause code for "unknown parameter" and the | |
421 | * "Unrecognized parameter" type is the same, we can | |
422 | * construct the parameters in INIT ACK by copying the | |
423 | * ERROR causes over. | |
424 | */ | |
425 | unk_param = (sctp_unrecognized_param_t *) | |
426 | ((__u8 *)(err_chunk->chunk_hdr) + | |
427 | sizeof(sctp_chunkhdr_t)); | |
428 | /* Replace the cause code with the "Unrecognized parameter" | |
429 | * parameter type. | |
430 | */ | |
431 | sctp_addto_chunk(repl, len, unk_param); | |
432 | sctp_chunk_free(err_chunk); | |
433 | } | |
434 | ||
df7deeb5 VY |
435 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); |
436 | ||
1da177e4 LT |
437 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
438 | ||
439 | /* | |
440 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
441 | * "Z" MUST NOT allocate any resources, nor keep any states for the | |
442 | * new association. Otherwise, "Z" will be vulnerable to resource | |
443 | * attacks. | |
444 | */ | |
445 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
446 | ||
447 | return SCTP_DISPOSITION_DELETE_TCB; | |
448 | ||
1da177e4 LT |
449 | nomem_init: |
450 | sctp_association_free(new_asoc); | |
451 | nomem: | |
df7deeb5 VY |
452 | if (err_chunk) |
453 | sctp_chunk_free(err_chunk); | |
1da177e4 LT |
454 | return SCTP_DISPOSITION_NOMEM; |
455 | } | |
456 | ||
457 | /* | |
458 | * Respond to a normal INIT ACK chunk. | |
459 | * We are the side that is initiating the association. | |
460 | * | |
461 | * Section: 5.1 Normal Establishment of an Association, C | |
462 | * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init | |
463 | * timer and leave COOKIE-WAIT state. "A" shall then send the State | |
464 | * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start | |
465 | * the T1-cookie timer, and enter the COOKIE-ECHOED state. | |
466 | * | |
467 | * Note: The COOKIE ECHO chunk can be bundled with any pending outbound | |
468 | * DATA chunks, but it MUST be the first chunk in the packet and | |
469 | * until the COOKIE ACK is returned the sender MUST NOT send any | |
470 | * other packets to the peer. | |
471 | * | |
472 | * Verification Tag: 3.3.3 | |
473 | * If the value of the Initiate Tag in a received INIT ACK chunk is | |
474 | * found to be 0, the receiver MUST treat it as an error and close the | |
475 | * association by transmitting an ABORT. | |
476 | * | |
477 | * Inputs | |
478 | * (endpoint, asoc, chunk) | |
479 | * | |
480 | * Outputs | |
481 | * (asoc, reply_msg, msg_up, timers, counters) | |
482 | * | |
483 | * The return value is the disposition of the chunk. | |
484 | */ | |
485 | sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, | |
486 | const struct sctp_association *asoc, | |
487 | const sctp_subtype_t type, | |
488 | void *arg, | |
489 | sctp_cmd_seq_t *commands) | |
490 | { | |
491 | struct sctp_chunk *chunk = arg; | |
492 | sctp_init_chunk_t *initchunk; | |
1da177e4 LT |
493 | struct sctp_chunk *err_chunk; |
494 | struct sctp_packet *packet; | |
1da177e4 LT |
495 | |
496 | if (!sctp_vtag_verify(chunk, asoc)) | |
497 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
498 | ||
1da177e4 LT |
499 | /* 6.10 Bundling |
500 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
501 | * SHUTDOWN COMPLETE with any other chunks. | |
502 | */ | |
503 | if (!chunk->singleton) | |
ece25dfa | 504 | return sctp_sf_violation_chunk(ep, asoc, type, arg, commands); |
1da177e4 | 505 | |
ece25dfa VY |
506 | /* Make sure that the INIT-ACK chunk has a valid length */ |
507 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_initack_chunk_t))) | |
508 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
509 | commands); | |
1da177e4 LT |
510 | /* Grab the INIT header. */ |
511 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
512 | ||
1da177e4 LT |
513 | /* Verify the INIT chunk before processing it. */ |
514 | err_chunk = NULL; | |
515 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
516 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
517 | &err_chunk)) { | |
518 | ||
853f4b50 VY |
519 | sctp_error_t error = SCTP_ERROR_NO_RESOURCE; |
520 | ||
1da177e4 | 521 | /* This chunk contains fatal error. It is to be discarded. |
d6701191 VY |
522 | * Send an ABORT, with causes. If there are no causes, |
523 | * then there wasn't enough memory. Just terminate | |
524 | * the association. | |
1da177e4 LT |
525 | */ |
526 | if (err_chunk) { | |
527 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
528 | (__u8 *)(err_chunk->chunk_hdr) + | |
529 | sizeof(sctp_chunkhdr_t), | |
530 | ntohs(err_chunk->chunk_hdr->length) - | |
531 | sizeof(sctp_chunkhdr_t)); | |
532 | ||
533 | sctp_chunk_free(err_chunk); | |
534 | ||
535 | if (packet) { | |
536 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
537 | SCTP_PACKET(packet)); | |
538 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
8de8c873 | 539 | error = SCTP_ERROR_INV_PARAM; |
1da177e4 | 540 | } |
1da177e4 | 541 | } |
bbd0d598 VY |
542 | |
543 | /* SCTP-AUTH, Section 6.3: | |
544 | * It should be noted that if the receiver wants to tear | |
545 | * down an association in an authenticated way only, the | |
546 | * handling of malformed packets should not result in | |
547 | * tearing down the association. | |
548 | * | |
549 | * This means that if we only want to abort associations | |
550 | * in an authenticated way (i.e AUTH+ABORT), then we | |
ac461a03 | 551 | * can't destroy this association just becuase the packet |
bbd0d598 VY |
552 | * was malformed. |
553 | */ | |
554 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
555 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
556 | ||
557 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
8de8c873 SS |
558 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, |
559 | asoc, chunk->transport); | |
1da177e4 LT |
560 | } |
561 | ||
562 | /* Tag the variable length parameters. Note that we never | |
563 | * convert the parameters in an INIT chunk. | |
564 | */ | |
565 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
566 | ||
567 | initchunk = (sctp_init_chunk_t *) chunk->chunk_hdr; | |
568 | ||
569 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT, | |
570 | SCTP_PEER_INIT(initchunk)); | |
571 | ||
3f7a87d2 FF |
572 | /* Reset init error count upon receipt of INIT-ACK. */ |
573 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); | |
574 | ||
1da177e4 LT |
575 | /* 5.1 C) "A" shall stop the T1-init timer and leave |
576 | * COOKIE-WAIT state. "A" shall then ... start the T1-cookie | |
577 | * timer, and enter the COOKIE-ECHOED state. | |
578 | */ | |
579 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
580 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
581 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
582 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
583 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
584 | SCTP_STATE(SCTP_STATE_COOKIE_ECHOED)); | |
585 | ||
730fc3d0 VY |
586 | /* SCTP-AUTH: genereate the assocition shared keys so that |
587 | * we can potentially signe the COOKIE-ECHO. | |
588 | */ | |
589 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_SHKEY, SCTP_NULL()); | |
590 | ||
1da177e4 LT |
591 | /* 5.1 C) "A" shall then send the State Cookie received in the |
592 | * INIT ACK chunk in a COOKIE ECHO chunk, ... | |
593 | */ | |
594 | /* If there is any errors to report, send the ERROR chunk generated | |
595 | * for unknown parameters as well. | |
596 | */ | |
597 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO, | |
598 | SCTP_CHUNK(err_chunk)); | |
599 | ||
600 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
601 | } |
602 | ||
603 | /* | |
604 | * Respond to a normal COOKIE ECHO chunk. | |
605 | * We are the side that is being asked for an association. | |
606 | * | |
607 | * Section: 5.1 Normal Establishment of an Association, D | |
608 | * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply | |
609 | * with a COOKIE ACK chunk after building a TCB and moving to | |
610 | * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with | |
611 | * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK | |
612 | * chunk MUST be the first chunk in the packet. | |
613 | * | |
614 | * IMPLEMENTATION NOTE: An implementation may choose to send the | |
615 | * Communication Up notification to the SCTP user upon reception | |
616 | * of a valid COOKIE ECHO chunk. | |
617 | * | |
618 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
619 | * D) Rules for packet carrying a COOKIE ECHO | |
620 | * | |
621 | * - When sending a COOKIE ECHO, the endpoint MUST use the value of the | |
622 | * Initial Tag received in the INIT ACK. | |
623 | * | |
624 | * - The receiver of a COOKIE ECHO follows the procedures in Section 5. | |
625 | * | |
626 | * Inputs | |
627 | * (endpoint, asoc, chunk) | |
628 | * | |
629 | * Outputs | |
630 | * (asoc, reply_msg, msg_up, timers, counters) | |
631 | * | |
632 | * The return value is the disposition of the chunk. | |
633 | */ | |
634 | sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep, | |
635 | const struct sctp_association *asoc, | |
636 | const sctp_subtype_t type, void *arg, | |
637 | sctp_cmd_seq_t *commands) | |
638 | { | |
639 | struct sctp_chunk *chunk = arg; | |
640 | struct sctp_association *new_asoc; | |
641 | sctp_init_chunk_t *peer_init; | |
642 | struct sctp_chunk *repl; | |
df7deeb5 | 643 | struct sctp_ulpevent *ev, *ai_ev = NULL; |
1da177e4 LT |
644 | int error = 0; |
645 | struct sctp_chunk *err_chk_p; | |
609ee467 | 646 | struct sock *sk; |
1da177e4 LT |
647 | |
648 | /* If the packet is an OOTB packet which is temporarily on the | |
649 | * control endpoint, respond with an ABORT. | |
650 | */ | |
8190f89d WY |
651 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) { |
652 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
ece25dfa | 653 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
8190f89d | 654 | } |
1da177e4 LT |
655 | |
656 | /* Make sure that the COOKIE_ECHO chunk has a valid length. | |
657 | * In this case, we check that we have enough for at least a | |
658 | * chunk header. More detailed verification is done | |
659 | * in sctp_unpack_cookie(). | |
660 | */ | |
661 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
662 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
663 | ||
609ee467 VY |
664 | /* If the endpoint is not listening or if the number of associations |
665 | * on the TCP-style socket exceed the max backlog, respond with an | |
666 | * ABORT. | |
667 | */ | |
668 | sk = ep->base.sk; | |
669 | if (!sctp_sstate(sk, LISTENING) || | |
670 | (sctp_style(sk, TCP) && sk_acceptq_is_full(sk))) | |
671 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
672 | ||
1da177e4 LT |
673 | /* "Decode" the chunk. We have no optional parameters so we |
674 | * are in good shape. | |
675 | */ | |
d808ad9a | 676 | chunk->subh.cookie_hdr = |
1da177e4 | 677 | (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
678 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
679 | sizeof(sctp_chunkhdr_t))) | |
680 | goto nomem; | |
1da177e4 LT |
681 | |
682 | /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint | |
683 | * "Z" will reply with a COOKIE ACK chunk after building a TCB | |
684 | * and moving to the ESTABLISHED state. | |
685 | */ | |
686 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
687 | &err_chk_p); | |
688 | ||
689 | /* FIXME: | |
690 | * If the re-build failed, what is the proper error path | |
691 | * from here? | |
692 | * | |
693 | * [We should abort the association. --piggy] | |
694 | */ | |
695 | if (!new_asoc) { | |
696 | /* FIXME: Several errors are possible. A bad cookie should | |
697 | * be silently discarded, but think about logging it too. | |
698 | */ | |
699 | switch (error) { | |
700 | case -SCTP_IERROR_NOMEM: | |
701 | goto nomem; | |
702 | ||
703 | case -SCTP_IERROR_STALE_COOKIE: | |
704 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
705 | err_chk_p); | |
706 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
707 | ||
708 | case -SCTP_IERROR_BAD_SIG: | |
709 | default: | |
710 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 711 | } |
1da177e4 LT |
712 | } |
713 | ||
1da177e4 | 714 | |
df7deeb5 VY |
715 | /* Delay state machine commands until later. |
716 | * | |
717 | * Re-build the bind address for the association is done in | |
1da177e4 LT |
718 | * the sctp_unpack_cookie() already. |
719 | */ | |
720 | /* This is a brand-new association, so these are not yet side | |
721 | * effects--it is safe to run them here. | |
722 | */ | |
723 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
724 | ||
725 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
6a1e5f33 | 726 | &chunk->subh.cookie_hdr->c.peer_addr, |
1da177e4 LT |
727 | peer_init, GFP_ATOMIC)) |
728 | goto nomem_init; | |
729 | ||
730fc3d0 VY |
730 | /* SCTP-AUTH: Now that we've populate required fields in |
731 | * sctp_process_init, set up the assocaition shared keys as | |
732 | * necessary so that we can potentially authenticate the ACK | |
733 | */ | |
734 | error = sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC); | |
735 | if (error) | |
736 | goto nomem_init; | |
737 | ||
bbd0d598 VY |
738 | /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo |
739 | * is supposed to be authenticated and we have to do delayed | |
740 | * authentication. We've just recreated the association using | |
741 | * the information in the cookie and now it's much easier to | |
742 | * do the authentication. | |
743 | */ | |
744 | if (chunk->auth_chunk) { | |
745 | struct sctp_chunk auth; | |
746 | sctp_ierror_t ret; | |
747 | ||
748 | /* set-up our fake chunk so that we can process it */ | |
749 | auth.skb = chunk->auth_chunk; | |
750 | auth.asoc = chunk->asoc; | |
751 | auth.sctp_hdr = chunk->sctp_hdr; | |
752 | auth.chunk_hdr = (sctp_chunkhdr_t *)skb_push(chunk->auth_chunk, | |
753 | sizeof(sctp_chunkhdr_t)); | |
754 | skb_pull(chunk->auth_chunk, sizeof(sctp_chunkhdr_t)); | |
755 | auth.transport = chunk->transport; | |
756 | ||
757 | ret = sctp_sf_authenticate(ep, new_asoc, type, &auth); | |
758 | ||
759 | /* We can now safely free the auth_chunk clone */ | |
760 | kfree_skb(chunk->auth_chunk); | |
761 | ||
762 | if (ret != SCTP_IERROR_NO_ERROR) { | |
763 | sctp_association_free(new_asoc); | |
764 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
765 | } | |
766 | } | |
767 | ||
1da177e4 LT |
768 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
769 | if (!repl) | |
df7deeb5 | 770 | goto nomem_init; |
1da177e4 LT |
771 | |
772 | /* RFC 2960 5.1 Normal Establishment of an Association | |
773 | * | |
774 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
775 | * send the Communication Up notification to the SCTP user | |
776 | * upon reception of a valid COOKIE ECHO chunk. | |
777 | */ | |
778 | ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0, | |
779 | new_asoc->c.sinit_num_ostreams, | |
780 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 781 | NULL, GFP_ATOMIC); |
1da177e4 LT |
782 | if (!ev) |
783 | goto nomem_ev; | |
784 | ||
d808ad9a | 785 | /* Sockets API Draft Section 5.3.1.6 |
0f3fffd8 | 786 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 787 | * delivers this notification to inform the application that of the |
0f3fffd8 | 788 | * peers requested adaptation layer. |
1da177e4 | 789 | */ |
0f3fffd8 ISJ |
790 | if (new_asoc->peer.adaptation_ind) { |
791 | ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc, | |
1da177e4 | 792 | GFP_ATOMIC); |
df7deeb5 VY |
793 | if (!ai_ev) |
794 | goto nomem_aiev; | |
795 | } | |
796 | ||
797 | /* Add all the state machine commands now since we've created | |
798 | * everything. This way we don't introduce memory corruptions | |
799 | * during side-effect processing and correclty count established | |
800 | * associations. | |
801 | */ | |
802 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
803 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
804 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
805 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
806 | SCTP_INC_STATS(SCTP_MIB_PASSIVEESTABS); | |
807 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
808 | ||
809 | if (new_asoc->autoclose) | |
810 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
811 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
812 | ||
df7deeb5 VY |
813 | /* This will send the COOKIE ACK */ |
814 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
815 | ||
816 | /* Queue the ASSOC_CHANGE event */ | |
817 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
818 | ||
819 | /* Send up the Adaptation Layer Indication event */ | |
820 | if (ai_ev) | |
1da177e4 | 821 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
df7deeb5 | 822 | SCTP_ULPEVENT(ai_ev)); |
1da177e4 LT |
823 | |
824 | return SCTP_DISPOSITION_CONSUME; | |
825 | ||
df7deeb5 VY |
826 | nomem_aiev: |
827 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
828 | nomem_ev: |
829 | sctp_chunk_free(repl); | |
1da177e4 LT |
830 | nomem_init: |
831 | sctp_association_free(new_asoc); | |
832 | nomem: | |
833 | return SCTP_DISPOSITION_NOMEM; | |
834 | } | |
835 | ||
836 | /* | |
837 | * Respond to a normal COOKIE ACK chunk. | |
838 | * We are the side that is being asked for an association. | |
839 | * | |
840 | * RFC 2960 5.1 Normal Establishment of an Association | |
841 | * | |
842 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the | |
843 | * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie | |
844 | * timer. It may also notify its ULP about the successful | |
845 | * establishment of the association with a Communication Up | |
846 | * notification (see Section 10). | |
847 | * | |
848 | * Verification Tag: | |
849 | * Inputs | |
850 | * (endpoint, asoc, chunk) | |
851 | * | |
852 | * Outputs | |
853 | * (asoc, reply_msg, msg_up, timers, counters) | |
854 | * | |
855 | * The return value is the disposition of the chunk. | |
856 | */ | |
857 | sctp_disposition_t sctp_sf_do_5_1E_ca(const struct sctp_endpoint *ep, | |
858 | const struct sctp_association *asoc, | |
859 | const sctp_subtype_t type, void *arg, | |
860 | sctp_cmd_seq_t *commands) | |
861 | { | |
862 | struct sctp_chunk *chunk = arg; | |
863 | struct sctp_ulpevent *ev; | |
864 | ||
865 | if (!sctp_vtag_verify(chunk, asoc)) | |
866 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
867 | ||
868 | /* Verify that the chunk length for the COOKIE-ACK is OK. | |
869 | * If we don't do this, any bundled chunks may be junked. | |
870 | */ | |
871 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
872 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
873 | commands); | |
874 | ||
875 | /* Reset init error count upon receipt of COOKIE-ACK, | |
876 | * to avoid problems with the managemement of this | |
877 | * counter in stale cookie situations when a transition back | |
878 | * from the COOKIE-ECHOED state to the COOKIE-WAIT | |
879 | * state is performed. | |
880 | */ | |
3f7a87d2 | 881 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); |
1da177e4 LT |
882 | |
883 | /* RFC 2960 5.1 Normal Establishment of an Association | |
884 | * | |
885 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move | |
886 | * from the COOKIE-ECHOED state to the ESTABLISHED state, | |
887 | * stopping the T1-cookie timer. | |
888 | */ | |
889 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
890 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
891 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
892 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
893 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
894 | SCTP_INC_STATS(SCTP_MIB_ACTIVEESTABS); | |
895 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
896 | if (asoc->autoclose) | |
897 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
898 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
1da177e4 LT |
899 | |
900 | /* It may also notify its ULP about the successful | |
901 | * establishment of the association with a Communication Up | |
902 | * notification (see Section 10). | |
903 | */ | |
904 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, | |
905 | 0, asoc->c.sinit_num_ostreams, | |
906 | asoc->c.sinit_max_instreams, | |
a5a35e76 | 907 | NULL, GFP_ATOMIC); |
1da177e4 LT |
908 | |
909 | if (!ev) | |
910 | goto nomem; | |
911 | ||
912 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
913 | ||
914 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 915 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 916 | * delivers this notification to inform the application that of the |
0f3fffd8 | 917 | * peers requested adaptation layer. |
1da177e4 | 918 | */ |
0f3fffd8 ISJ |
919 | if (asoc->peer.adaptation_ind) { |
920 | ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); | |
1da177e4 LT |
921 | if (!ev) |
922 | goto nomem; | |
923 | ||
924 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
925 | SCTP_ULPEVENT(ev)); | |
926 | } | |
927 | ||
928 | return SCTP_DISPOSITION_CONSUME; | |
929 | nomem: | |
930 | return SCTP_DISPOSITION_NOMEM; | |
931 | } | |
932 | ||
933 | /* Generate and sendout a heartbeat packet. */ | |
934 | static sctp_disposition_t sctp_sf_heartbeat(const struct sctp_endpoint *ep, | |
935 | const struct sctp_association *asoc, | |
936 | const sctp_subtype_t type, | |
937 | void *arg, | |
938 | sctp_cmd_seq_t *commands) | |
939 | { | |
940 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
941 | struct sctp_chunk *reply; | |
942 | sctp_sender_hb_info_t hbinfo; | |
943 | size_t paylen = 0; | |
944 | ||
945 | hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO; | |
946 | hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t)); | |
63de08f4 | 947 | hbinfo.daddr = transport->ipaddr; |
1da177e4 | 948 | hbinfo.sent_at = jiffies; |
ad8fec17 | 949 | hbinfo.hb_nonce = transport->hb_nonce; |
1da177e4 LT |
950 | |
951 | /* Send a heartbeat to our peer. */ | |
952 | paylen = sizeof(sctp_sender_hb_info_t); | |
953 | reply = sctp_make_heartbeat(asoc, transport, &hbinfo, paylen); | |
954 | if (!reply) | |
955 | return SCTP_DISPOSITION_NOMEM; | |
956 | ||
957 | /* Set rto_pending indicating that an RTT measurement | |
958 | * is started with this heartbeat chunk. | |
959 | */ | |
960 | sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING, | |
961 | SCTP_TRANSPORT(transport)); | |
962 | ||
963 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
964 | return SCTP_DISPOSITION_CONSUME; | |
965 | } | |
966 | ||
967 | /* Generate a HEARTBEAT packet on the given transport. */ | |
968 | sctp_disposition_t sctp_sf_sendbeat_8_3(const struct sctp_endpoint *ep, | |
969 | const struct sctp_association *asoc, | |
970 | const sctp_subtype_t type, | |
971 | void *arg, | |
972 | sctp_cmd_seq_t *commands) | |
973 | { | |
974 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
975 | ||
b9f84786 | 976 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
977 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
978 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
979 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
980 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 981 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
982 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
983 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
984 | return SCTP_DISPOSITION_DELETE_TCB; | |
985 | } | |
986 | ||
987 | /* Section 3.3.5. | |
988 | * The Sender-specific Heartbeat Info field should normally include | |
989 | * information about the sender's current time when this HEARTBEAT | |
990 | * chunk is sent and the destination transport address to which this | |
991 | * HEARTBEAT is sent (see Section 8.3). | |
992 | */ | |
993 | ||
52ccb8e9 | 994 | if (transport->param_flags & SPP_HB_ENABLE) { |
1da177e4 LT |
995 | if (SCTP_DISPOSITION_NOMEM == |
996 | sctp_sf_heartbeat(ep, asoc, type, arg, | |
997 | commands)) | |
998 | return SCTP_DISPOSITION_NOMEM; | |
245cba7e | 999 | |
1da177e4 LT |
1000 | /* Set transport error counter and association error counter |
1001 | * when sending heartbeat. | |
1002 | */ | |
7e99013a | 1003 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
1da177e4 LT |
1004 | SCTP_TRANSPORT(transport)); |
1005 | } | |
245cba7e VY |
1006 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_IDLE, |
1007 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
1008 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE, |
1009 | SCTP_TRANSPORT(transport)); | |
1010 | ||
d808ad9a | 1011 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
1012 | } |
1013 | ||
1014 | /* | |
1015 | * Process an heartbeat request. | |
1016 | * | |
1017 | * Section: 8.3 Path Heartbeat | |
1018 | * The receiver of the HEARTBEAT should immediately respond with a | |
1019 | * HEARTBEAT ACK that contains the Heartbeat Information field copied | |
1020 | * from the received HEARTBEAT chunk. | |
1021 | * | |
1022 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1023 | * When receiving an SCTP packet, the endpoint MUST ensure that the | |
1024 | * value in the Verification Tag field of the received SCTP packet | |
1025 | * matches its own Tag. If the received Verification Tag value does not | |
1026 | * match the receiver's own tag value, the receiver shall silently | |
1027 | * discard the packet and shall not process it any further except for | |
1028 | * those cases listed in Section 8.5.1 below. | |
1029 | * | |
1030 | * Inputs | |
1031 | * (endpoint, asoc, chunk) | |
1032 | * | |
1033 | * Outputs | |
1034 | * (asoc, reply_msg, msg_up, timers, counters) | |
1035 | * | |
1036 | * The return value is the disposition of the chunk. | |
1037 | */ | |
1038 | sctp_disposition_t sctp_sf_beat_8_3(const struct sctp_endpoint *ep, | |
1039 | const struct sctp_association *asoc, | |
1040 | const sctp_subtype_t type, | |
1041 | void *arg, | |
1042 | sctp_cmd_seq_t *commands) | |
1043 | { | |
1044 | struct sctp_chunk *chunk = arg; | |
1045 | struct sctp_chunk *reply; | |
1046 | size_t paylen = 0; | |
1047 | ||
1048 | if (!sctp_vtag_verify(chunk, asoc)) | |
1049 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1050 | ||
1051 | /* Make sure that the HEARTBEAT chunk has a valid length. */ | |
1052 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
1053 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1054 | commands); | |
1055 | ||
1056 | /* 8.3 The receiver of the HEARTBEAT should immediately | |
1057 | * respond with a HEARTBEAT ACK that contains the Heartbeat | |
1058 | * Information field copied from the received HEARTBEAT chunk. | |
1059 | */ | |
1060 | chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data; | |
1061 | paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t); | |
62b08083 SS |
1062 | if (!pskb_pull(chunk->skb, paylen)) |
1063 | goto nomem; | |
1da177e4 LT |
1064 | |
1065 | reply = sctp_make_heartbeat_ack(asoc, chunk, | |
1066 | chunk->subh.hb_hdr, paylen); | |
1067 | if (!reply) | |
1068 | goto nomem; | |
1069 | ||
1070 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
1071 | return SCTP_DISPOSITION_CONSUME; | |
1072 | ||
1073 | nomem: | |
1074 | return SCTP_DISPOSITION_NOMEM; | |
1075 | } | |
1076 | ||
1077 | /* | |
1078 | * Process the returning HEARTBEAT ACK. | |
1079 | * | |
1080 | * Section: 8.3 Path Heartbeat | |
1081 | * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT | |
1082 | * should clear the error counter of the destination transport | |
1083 | * address to which the HEARTBEAT was sent, and mark the destination | |
1084 | * transport address as active if it is not so marked. The endpoint may | |
1085 | * optionally report to the upper layer when an inactive destination | |
1086 | * address is marked as active due to the reception of the latest | |
1087 | * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also | |
1088 | * clear the association overall error count as well (as defined | |
1089 | * in section 8.1). | |
1090 | * | |
1091 | * The receiver of the HEARTBEAT ACK should also perform an RTT | |
1092 | * measurement for that destination transport address using the time | |
1093 | * value carried in the HEARTBEAT ACK chunk. | |
1094 | * | |
1095 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1096 | * | |
1097 | * Inputs | |
1098 | * (endpoint, asoc, chunk) | |
1099 | * | |
1100 | * Outputs | |
1101 | * (asoc, reply_msg, msg_up, timers, counters) | |
1102 | * | |
1103 | * The return value is the disposition of the chunk. | |
1104 | */ | |
1105 | sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep, | |
1106 | const struct sctp_association *asoc, | |
1107 | const sctp_subtype_t type, | |
1108 | void *arg, | |
1109 | sctp_cmd_seq_t *commands) | |
1110 | { | |
1111 | struct sctp_chunk *chunk = arg; | |
1112 | union sctp_addr from_addr; | |
1113 | struct sctp_transport *link; | |
1114 | sctp_sender_hb_info_t *hbinfo; | |
1115 | unsigned long max_interval; | |
1116 | ||
1117 | if (!sctp_vtag_verify(chunk, asoc)) | |
1118 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1119 | ||
1120 | /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */ | |
dadb50cc WY |
1121 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t) + |
1122 | sizeof(sctp_sender_hb_info_t))) | |
1da177e4 LT |
1123 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, |
1124 | commands); | |
1125 | ||
1126 | hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; | |
a601266e VY |
1127 | /* Make sure that the length of the parameter is what we expect */ |
1128 | if (ntohs(hbinfo->param_hdr.length) != | |
1129 | sizeof(sctp_sender_hb_info_t)) { | |
1130 | return SCTP_DISPOSITION_DISCARD; | |
1131 | } | |
1132 | ||
1da177e4 | 1133 | from_addr = hbinfo->daddr; |
63de08f4 | 1134 | link = sctp_assoc_lookup_paddr(asoc, &from_addr); |
1da177e4 LT |
1135 | |
1136 | /* This should never happen, but lets log it if so. */ | |
3f7a87d2 FF |
1137 | if (unlikely(!link)) { |
1138 | if (from_addr.sa.sa_family == AF_INET6) { | |
d99fa429 WY |
1139 | if (net_ratelimit()) |
1140 | printk(KERN_WARNING | |
5b095d98 | 1141 | "%s association %p could not find address %pI6\n", |
0dc47877 | 1142 | __func__, |
d99fa429 | 1143 | asoc, |
fdb46ee7 | 1144 | &from_addr.v6.sin6_addr); |
3f7a87d2 | 1145 | } else { |
d99fa429 WY |
1146 | if (net_ratelimit()) |
1147 | printk(KERN_WARNING | |
21454aaa | 1148 | "%s association %p could not find address %pI4\n", |
0dc47877 | 1149 | __func__, |
d99fa429 | 1150 | asoc, |
21454aaa | 1151 | &from_addr.v4.sin_addr.s_addr); |
3f7a87d2 | 1152 | } |
1da177e4 LT |
1153 | return SCTP_DISPOSITION_DISCARD; |
1154 | } | |
1155 | ||
ad8fec17 SS |
1156 | /* Validate the 64-bit random nonce. */ |
1157 | if (hbinfo->hb_nonce != link->hb_nonce) | |
1158 | return SCTP_DISPOSITION_DISCARD; | |
1159 | ||
52ccb8e9 | 1160 | max_interval = link->hbinterval + link->rto; |
1da177e4 LT |
1161 | |
1162 | /* Check if the timestamp looks valid. */ | |
1163 | if (time_after(hbinfo->sent_at, jiffies) || | |
1164 | time_after(jiffies, hbinfo->sent_at + max_interval)) { | |
9ee46f1d | 1165 | SCTP_DEBUG_PRINTK("%s: HEARTBEAT ACK with invalid timestamp " |
1da177e4 | 1166 | "received for transport: %p\n", |
0dc47877 | 1167 | __func__, link); |
1da177e4 LT |
1168 | return SCTP_DISPOSITION_DISCARD; |
1169 | } | |
1170 | ||
1171 | /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of | |
1172 | * the HEARTBEAT should clear the error counter of the | |
1173 | * destination transport address to which the HEARTBEAT was | |
1174 | * sent and mark the destination transport address as active if | |
1175 | * it is not so marked. | |
1176 | */ | |
1177 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link)); | |
1178 | ||
1179 | return SCTP_DISPOSITION_CONSUME; | |
1180 | } | |
1181 | ||
1182 | /* Helper function to send out an abort for the restart | |
1183 | * condition. | |
1184 | */ | |
1185 | static int sctp_sf_send_restart_abort(union sctp_addr *ssa, | |
1186 | struct sctp_chunk *init, | |
1187 | sctp_cmd_seq_t *commands) | |
1188 | { | |
1189 | int len; | |
1190 | struct sctp_packet *pkt; | |
1191 | union sctp_addr_param *addrparm; | |
1192 | struct sctp_errhdr *errhdr; | |
1193 | struct sctp_endpoint *ep; | |
1194 | char buffer[sizeof(struct sctp_errhdr)+sizeof(union sctp_addr_param)]; | |
1195 | struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family); | |
1196 | ||
1197 | /* Build the error on the stack. We are way to malloc crazy | |
1198 | * throughout the code today. | |
1199 | */ | |
1200 | errhdr = (struct sctp_errhdr *)buffer; | |
1201 | addrparm = (union sctp_addr_param *)errhdr->variable; | |
1202 | ||
1203 | /* Copy into a parm format. */ | |
1204 | len = af->to_addr_param(ssa, addrparm); | |
1205 | len += sizeof(sctp_errhdr_t); | |
1206 | ||
1207 | errhdr->cause = SCTP_ERROR_RESTART; | |
1208 | errhdr->length = htons(len); | |
1209 | ||
1210 | /* Assign to the control socket. */ | |
1211 | ep = sctp_sk((sctp_get_ctl_sock()))->ep; | |
1212 | ||
1213 | /* Association is NULL since this may be a restart attack and we | |
1214 | * want to send back the attacker's vtag. | |
1215 | */ | |
1216 | pkt = sctp_abort_pkt_new(ep, NULL, init, errhdr, len); | |
1217 | ||
1218 | if (!pkt) | |
1219 | goto out; | |
1220 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt)); | |
1221 | ||
1222 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1223 | ||
1224 | /* Discard the rest of the inbound packet. */ | |
1225 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); | |
1226 | ||
1227 | out: | |
1228 | /* Even if there is no memory, treat as a failure so | |
1229 | * the packet will get dropped. | |
1230 | */ | |
1231 | return 0; | |
1232 | } | |
1233 | ||
1234 | /* A restart is occurring, check to make sure no new addresses | |
1235 | * are being added as we may be under a takeover attack. | |
1236 | */ | |
1237 | static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, | |
1238 | const struct sctp_association *asoc, | |
1239 | struct sctp_chunk *init, | |
1240 | sctp_cmd_seq_t *commands) | |
1241 | { | |
1242 | struct sctp_transport *new_addr, *addr; | |
1da177e4 LT |
1243 | int found; |
1244 | ||
1245 | /* Implementor's Guide - Sectin 5.2.2 | |
1246 | * ... | |
1247 | * Before responding the endpoint MUST check to see if the | |
1248 | * unexpected INIT adds new addresses to the association. If new | |
1249 | * addresses are added to the association, the endpoint MUST respond | |
1250 | * with an ABORT.. | |
1251 | */ | |
1252 | ||
1253 | /* Search through all current addresses and make sure | |
1254 | * we aren't adding any new ones. | |
1255 | */ | |
1256 | new_addr = NULL; | |
1257 | found = 0; | |
1258 | ||
9dbc15f0 RD |
1259 | list_for_each_entry(new_addr, &new_asoc->peer.transport_addr_list, |
1260 | transports) { | |
1da177e4 | 1261 | found = 0; |
9dbc15f0 RD |
1262 | list_for_each_entry(addr, &asoc->peer.transport_addr_list, |
1263 | transports) { | |
5f242a13 AV |
1264 | if (sctp_cmp_addr_exact(&new_addr->ipaddr, |
1265 | &addr->ipaddr)) { | |
1da177e4 LT |
1266 | found = 1; |
1267 | break; | |
1268 | } | |
1269 | } | |
1270 | if (!found) | |
1271 | break; | |
1272 | } | |
1273 | ||
1274 | /* If a new address was added, ABORT the sender. */ | |
1275 | if (!found && new_addr) { | |
7dd8a582 | 1276 | sctp_sf_send_restart_abort(&new_addr->ipaddr, init, commands); |
1da177e4 LT |
1277 | } |
1278 | ||
1279 | /* Return success if all addresses were found. */ | |
1280 | return found; | |
1281 | } | |
1282 | ||
1283 | /* Populate the verification/tie tags based on overlapping INIT | |
1284 | * scenario. | |
1285 | * | |
1286 | * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state. | |
1287 | */ | |
1288 | static void sctp_tietags_populate(struct sctp_association *new_asoc, | |
1289 | const struct sctp_association *asoc) | |
1290 | { | |
1291 | switch (asoc->state) { | |
1292 | ||
1293 | /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */ | |
1294 | ||
1295 | case SCTP_STATE_COOKIE_WAIT: | |
1296 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1297 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1298 | new_asoc->c.peer_ttag = 0; | |
1299 | break; | |
1300 | ||
1301 | case SCTP_STATE_COOKIE_ECHOED: | |
1302 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1303 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1304 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1305 | break; | |
1306 | ||
1307 | /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED, | |
1308 | * COOKIE-WAIT and SHUTDOWN-ACK-SENT | |
1309 | */ | |
1310 | default: | |
1311 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1312 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1313 | break; | |
3ff50b79 | 1314 | } |
1da177e4 LT |
1315 | |
1316 | /* Other parameters for the endpoint SHOULD be copied from the | |
1317 | * existing parameters of the association (e.g. number of | |
1318 | * outbound streams) into the INIT ACK and cookie. | |
1319 | */ | |
1320 | new_asoc->rwnd = asoc->rwnd; | |
1321 | new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams; | |
1322 | new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams; | |
1323 | new_asoc->c.initial_tsn = asoc->c.initial_tsn; | |
1324 | } | |
1325 | ||
1326 | /* | |
1327 | * Compare vtag/tietag values to determine unexpected COOKIE-ECHO | |
1328 | * handling action. | |
1329 | * | |
1330 | * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists. | |
1331 | * | |
1332 | * Returns value representing action to be taken. These action values | |
1333 | * correspond to Action/Description values in RFC 2960, Table 2. | |
1334 | */ | |
1335 | static char sctp_tietags_compare(struct sctp_association *new_asoc, | |
1336 | const struct sctp_association *asoc) | |
1337 | { | |
1338 | /* In this case, the peer may have restarted. */ | |
1339 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1340 | (asoc->c.peer_vtag != new_asoc->c.peer_vtag) && | |
1341 | (asoc->c.my_vtag == new_asoc->c.my_ttag) && | |
1342 | (asoc->c.peer_vtag == new_asoc->c.peer_ttag)) | |
1343 | return 'A'; | |
1344 | ||
1345 | /* Collision case B. */ | |
1346 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1347 | ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) || | |
1348 | (0 == asoc->c.peer_vtag))) { | |
1349 | return 'B'; | |
1350 | } | |
1351 | ||
1352 | /* Collision case D. */ | |
1353 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1354 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag)) | |
1355 | return 'D'; | |
1356 | ||
1357 | /* Collision case C. */ | |
1358 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1359 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag) && | |
1360 | (0 == new_asoc->c.my_ttag) && | |
1361 | (0 == new_asoc->c.peer_ttag)) | |
1362 | return 'C'; | |
1363 | ||
1364 | /* No match to any of the special cases; discard this packet. */ | |
1365 | return 'E'; | |
1366 | } | |
1367 | ||
1368 | /* Common helper routine for both duplicate and simulataneous INIT | |
1369 | * chunk handling. | |
1370 | */ | |
1371 | static sctp_disposition_t sctp_sf_do_unexpected_init( | |
1372 | const struct sctp_endpoint *ep, | |
1373 | const struct sctp_association *asoc, | |
1374 | const sctp_subtype_t type, | |
1375 | void *arg, sctp_cmd_seq_t *commands) | |
1376 | { | |
1377 | sctp_disposition_t retval; | |
1378 | struct sctp_chunk *chunk = arg; | |
1379 | struct sctp_chunk *repl; | |
1380 | struct sctp_association *new_asoc; | |
1381 | struct sctp_chunk *err_chunk; | |
1382 | struct sctp_packet *packet; | |
1383 | sctp_unrecognized_param_t *unk_param; | |
1384 | int len; | |
1385 | ||
1386 | /* 6.10 Bundling | |
1387 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
1388 | * SHUTDOWN COMPLETE with any other chunks. | |
1389 | * | |
1390 | * IG Section 2.11.2 | |
1391 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
1392 | * enforce these rules by silently discarding an arriving packet | |
1393 | * with an INIT chunk that is bundled with other chunks. | |
1394 | */ | |
1395 | if (!chunk->singleton) | |
1396 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1397 | ||
1398 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification | |
d808ad9a | 1399 | * Tag. |
1da177e4 LT |
1400 | */ |
1401 | if (chunk->sctp_hdr->vtag != 0) | |
1402 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
1403 | ||
1404 | /* Make sure that the INIT chunk has a valid length. | |
1405 | * In this case, we generate a protocol violation since we have | |
1406 | * an association established. | |
1407 | */ | |
1408 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
1409 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1410 | commands); | |
1411 | /* Grab the INIT header. */ | |
1412 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
1413 | ||
1414 | /* Tag the variable length parameters. */ | |
1415 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
1416 | ||
1417 | /* Verify the INIT chunk before processing it. */ | |
1418 | err_chunk = NULL; | |
1419 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
1420 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
1421 | &err_chunk)) { | |
1422 | /* This chunk contains fatal error. It is to be discarded. | |
1423 | * Send an ABORT, with causes if there is any. | |
1424 | */ | |
1425 | if (err_chunk) { | |
1426 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
1427 | (__u8 *)(err_chunk->chunk_hdr) + | |
1428 | sizeof(sctp_chunkhdr_t), | |
1429 | ntohs(err_chunk->chunk_hdr->length) - | |
1430 | sizeof(sctp_chunkhdr_t)); | |
1431 | ||
1432 | if (packet) { | |
1433 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
1434 | SCTP_PACKET(packet)); | |
1435 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1436 | retval = SCTP_DISPOSITION_CONSUME; | |
1437 | } else { | |
1438 | retval = SCTP_DISPOSITION_NOMEM; | |
1439 | } | |
1440 | goto cleanup; | |
1441 | } else { | |
1442 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
1443 | commands); | |
1444 | } | |
1445 | } | |
1446 | ||
1447 | /* | |
1448 | * Other parameters for the endpoint SHOULD be copied from the | |
1449 | * existing parameters of the association (e.g. number of | |
1450 | * outbound streams) into the INIT ACK and cookie. | |
1451 | * FIXME: We are copying parameters from the endpoint not the | |
1452 | * association. | |
1453 | */ | |
1454 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
1455 | if (!new_asoc) | |
1456 | goto nomem; | |
1457 | ||
409b95af VY |
1458 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, |
1459 | sctp_scope(sctp_source(chunk)), GFP_ATOMIC) < 0) | |
1460 | goto nomem; | |
1461 | ||
1da177e4 LT |
1462 | /* In the outbound INIT ACK the endpoint MUST copy its current |
1463 | * Verification Tag and Peers Verification tag into a reserved | |
1464 | * place (local tie-tag and per tie-tag) within the state cookie. | |
1465 | */ | |
1466 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1467 | sctp_source(chunk), | |
1468 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
df7deeb5 VY |
1469 | GFP_ATOMIC)) |
1470 | goto nomem; | |
1da177e4 LT |
1471 | |
1472 | /* Make sure no new addresses are being added during the | |
1473 | * restart. Do not do this check for COOKIE-WAIT state, | |
1474 | * since there are no peer addresses to check against. | |
1475 | * Upon return an ABORT will have been sent if needed. | |
1476 | */ | |
1477 | if (!sctp_state(asoc, COOKIE_WAIT)) { | |
1478 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, | |
1479 | commands)) { | |
1480 | retval = SCTP_DISPOSITION_CONSUME; | |
df7deeb5 | 1481 | goto nomem_retval; |
1da177e4 LT |
1482 | } |
1483 | } | |
1484 | ||
1485 | sctp_tietags_populate(new_asoc, asoc); | |
1486 | ||
1487 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ | |
1488 | ||
1489 | /* If there are errors need to be reported for unknown parameters, | |
1490 | * make sure to reserve enough room in the INIT ACK for them. | |
1491 | */ | |
1492 | len = 0; | |
1493 | if (err_chunk) { | |
1494 | len = ntohs(err_chunk->chunk_hdr->length) - | |
1495 | sizeof(sctp_chunkhdr_t); | |
1496 | } | |
1497 | ||
1da177e4 LT |
1498 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); |
1499 | if (!repl) | |
1500 | goto nomem; | |
1501 | ||
1502 | /* If there are errors need to be reported for unknown parameters, | |
1503 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
1504 | * parameter. | |
1505 | */ | |
1506 | if (err_chunk) { | |
1507 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
1508 | * ERROR chunk generated by sctp_verify_init(). Since the | |
1509 | * error cause code for "unknown parameter" and the | |
1510 | * "Unrecognized parameter" type is the same, we can | |
1511 | * construct the parameters in INIT ACK by copying the | |
1512 | * ERROR causes over. | |
1513 | */ | |
1514 | unk_param = (sctp_unrecognized_param_t *) | |
1515 | ((__u8 *)(err_chunk->chunk_hdr) + | |
1516 | sizeof(sctp_chunkhdr_t)); | |
1517 | /* Replace the cause code with the "Unrecognized parameter" | |
1518 | * parameter type. | |
1519 | */ | |
1520 | sctp_addto_chunk(repl, len, unk_param); | |
1521 | } | |
1522 | ||
1523 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1524 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1525 | ||
1526 | /* | |
1527 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
1528 | * "Z" MUST NOT allocate any resources for this new association. | |
1529 | * Otherwise, "Z" will be vulnerable to resource attacks. | |
1530 | */ | |
1531 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1532 | retval = SCTP_DISPOSITION_CONSUME; | |
1533 | ||
df7deeb5 VY |
1534 | return retval; |
1535 | ||
1536 | nomem: | |
1537 | retval = SCTP_DISPOSITION_NOMEM; | |
1538 | nomem_retval: | |
1539 | if (new_asoc) | |
1540 | sctp_association_free(new_asoc); | |
1da177e4 LT |
1541 | cleanup: |
1542 | if (err_chunk) | |
1543 | sctp_chunk_free(err_chunk); | |
1544 | return retval; | |
1da177e4 LT |
1545 | } |
1546 | ||
1547 | /* | |
1548 | * Handle simultanous INIT. | |
1549 | * This means we started an INIT and then we got an INIT request from | |
1550 | * our peer. | |
1551 | * | |
1552 | * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B) | |
1553 | * This usually indicates an initialization collision, i.e., each | |
1554 | * endpoint is attempting, at about the same time, to establish an | |
1555 | * association with the other endpoint. | |
1556 | * | |
1557 | * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an | |
1558 | * endpoint MUST respond with an INIT ACK using the same parameters it | |
1559 | * sent in its original INIT chunk (including its Verification Tag, | |
1560 | * unchanged). These original parameters are combined with those from the | |
1561 | * newly received INIT chunk. The endpoint shall also generate a State | |
1562 | * Cookie with the INIT ACK. The endpoint uses the parameters sent in its | |
1563 | * INIT to calculate the State Cookie. | |
1564 | * | |
1565 | * After that, the endpoint MUST NOT change its state, the T1-init | |
1566 | * timer shall be left running and the corresponding TCB MUST NOT be | |
1567 | * destroyed. The normal procedures for handling State Cookies when | |
1568 | * a TCB exists will resolve the duplicate INITs to a single association. | |
1569 | * | |
1570 | * For an endpoint that is in the COOKIE-ECHOED state it MUST populate | |
1571 | * its Tie-Tags with the Tag information of itself and its peer (see | |
1572 | * section 5.2.2 for a description of the Tie-Tags). | |
1573 | * | |
1574 | * Verification Tag: Not explicit, but an INIT can not have a valid | |
1575 | * verification tag, so we skip the check. | |
1576 | * | |
1577 | * Inputs | |
1578 | * (endpoint, asoc, chunk) | |
1579 | * | |
1580 | * Outputs | |
1581 | * (asoc, reply_msg, msg_up, timers, counters) | |
1582 | * | |
1583 | * The return value is the disposition of the chunk. | |
1584 | */ | |
1585 | sctp_disposition_t sctp_sf_do_5_2_1_siminit(const struct sctp_endpoint *ep, | |
1586 | const struct sctp_association *asoc, | |
1587 | const sctp_subtype_t type, | |
1588 | void *arg, | |
1589 | sctp_cmd_seq_t *commands) | |
1590 | { | |
1591 | /* Call helper to do the real work for both simulataneous and | |
1592 | * duplicate INIT chunk handling. | |
1593 | */ | |
1594 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1595 | } | |
1596 | ||
1597 | /* | |
1598 | * Handle duplicated INIT messages. These are usually delayed | |
1599 | * restransmissions. | |
1600 | * | |
1601 | * Section: 5.2.2 Unexpected INIT in States Other than CLOSED, | |
1602 | * COOKIE-ECHOED and COOKIE-WAIT | |
1603 | * | |
1604 | * Unless otherwise stated, upon reception of an unexpected INIT for | |
1605 | * this association, the endpoint shall generate an INIT ACK with a | |
1606 | * State Cookie. In the outbound INIT ACK the endpoint MUST copy its | |
1607 | * current Verification Tag and peer's Verification Tag into a reserved | |
1608 | * place within the state cookie. We shall refer to these locations as | |
1609 | * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet | |
1610 | * containing this INIT ACK MUST carry a Verification Tag value equal to | |
1611 | * the Initiation Tag found in the unexpected INIT. And the INIT ACK | |
1612 | * MUST contain a new Initiation Tag (randomly generated see Section | |
1613 | * 5.3.1). Other parameters for the endpoint SHOULD be copied from the | |
1614 | * existing parameters of the association (e.g. number of outbound | |
1615 | * streams) into the INIT ACK and cookie. | |
1616 | * | |
1617 | * After sending out the INIT ACK, the endpoint shall take no further | |
1618 | * actions, i.e., the existing association, including its current state, | |
1619 | * and the corresponding TCB MUST NOT be changed. | |
1620 | * | |
1621 | * Note: Only when a TCB exists and the association is not in a COOKIE- | |
1622 | * WAIT state are the Tie-Tags populated. For a normal association INIT | |
1623 | * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be | |
1624 | * set to 0 (indicating that no previous TCB existed). The INIT ACK and | |
1625 | * State Cookie are populated as specified in section 5.2.1. | |
1626 | * | |
1627 | * Verification Tag: Not specified, but an INIT has no way of knowing | |
1628 | * what the verification tag could be, so we ignore it. | |
1629 | * | |
1630 | * Inputs | |
1631 | * (endpoint, asoc, chunk) | |
1632 | * | |
1633 | * Outputs | |
1634 | * (asoc, reply_msg, msg_up, timers, counters) | |
1635 | * | |
1636 | * The return value is the disposition of the chunk. | |
1637 | */ | |
1638 | sctp_disposition_t sctp_sf_do_5_2_2_dupinit(const struct sctp_endpoint *ep, | |
1639 | const struct sctp_association *asoc, | |
1640 | const sctp_subtype_t type, | |
1641 | void *arg, | |
1642 | sctp_cmd_seq_t *commands) | |
1643 | { | |
1644 | /* Call helper to do the real work for both simulataneous and | |
1645 | * duplicate INIT chunk handling. | |
1646 | */ | |
1647 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1648 | } | |
1649 | ||
1650 | ||
610ab73a VY |
1651 | /* |
1652 | * Unexpected INIT-ACK handler. | |
1653 | * | |
1654 | * Section 5.2.3 | |
1655 | * If an INIT ACK received by an endpoint in any state other than the | |
1656 | * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk. | |
1657 | * An unexpected INIT ACK usually indicates the processing of an old or | |
1658 | * duplicated INIT chunk. | |
1659 | */ | |
1660 | sctp_disposition_t sctp_sf_do_5_2_3_initack(const struct sctp_endpoint *ep, | |
1661 | const struct sctp_association *asoc, | |
1662 | const sctp_subtype_t type, | |
1663 | void *arg, sctp_cmd_seq_t *commands) | |
1664 | { | |
1665 | /* Per the above section, we'll discard the chunk if we have an | |
1666 | * endpoint. If this is an OOTB INIT-ACK, treat it as such. | |
1667 | */ | |
d808ad9a | 1668 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) |
610ab73a VY |
1669 | return sctp_sf_ootb(ep, asoc, type, arg, commands); |
1670 | else | |
1671 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
1672 | } | |
1da177e4 LT |
1673 | |
1674 | /* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A') | |
1675 | * | |
1676 | * Section 5.2.4 | |
1677 | * A) In this case, the peer may have restarted. | |
1678 | */ | |
1679 | static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep, | |
1680 | const struct sctp_association *asoc, | |
1681 | struct sctp_chunk *chunk, | |
1682 | sctp_cmd_seq_t *commands, | |
1683 | struct sctp_association *new_asoc) | |
1684 | { | |
1685 | sctp_init_chunk_t *peer_init; | |
1686 | struct sctp_ulpevent *ev; | |
1687 | struct sctp_chunk *repl; | |
1688 | struct sctp_chunk *err; | |
1689 | sctp_disposition_t disposition; | |
1690 | ||
1691 | /* new_asoc is a brand-new association, so these are not yet | |
1692 | * side effects--it is safe to run them here. | |
1693 | */ | |
1694 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1695 | ||
1696 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1697 | sctp_source(chunk), peer_init, | |
1698 | GFP_ATOMIC)) | |
1699 | goto nomem; | |
1700 | ||
1701 | /* Make sure no new addresses are being added during the | |
1702 | * restart. Though this is a pretty complicated attack | |
1703 | * since you'd have to get inside the cookie. | |
1704 | */ | |
1705 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) { | |
1706 | return SCTP_DISPOSITION_CONSUME; | |
1707 | } | |
1708 | ||
1709 | /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes | |
1710 | * the peer has restarted (Action A), it MUST NOT setup a new | |
1711 | * association but instead resend the SHUTDOWN ACK and send an ERROR | |
1712 | * chunk with a "Cookie Received while Shutting Down" error cause to | |
1713 | * its peer. | |
1714 | */ | |
1715 | if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) { | |
1716 | disposition = sctp_sf_do_9_2_reshutack(ep, asoc, | |
1717 | SCTP_ST_CHUNK(chunk->chunk_hdr->type), | |
1718 | chunk, commands); | |
1719 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
1720 | goto nomem; | |
1721 | ||
1722 | err = sctp_make_op_error(asoc, chunk, | |
1723 | SCTP_ERROR_COOKIE_IN_SHUTDOWN, | |
6383cfb3 | 1724 | NULL, 0, 0); |
1da177e4 LT |
1725 | if (err) |
1726 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1727 | SCTP_CHUNK(err)); | |
1728 | ||
1729 | return SCTP_DISPOSITION_CONSUME; | |
1730 | } | |
1731 | ||
1732 | /* For now, fail any unsent/unacked data. Consider the optional | |
1733 | * choice of resending of this data. | |
1734 | */ | |
1735 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL()); | |
1736 | ||
1da177e4 LT |
1737 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
1738 | if (!repl) | |
1739 | goto nomem; | |
1740 | ||
1da177e4 LT |
1741 | /* Report association restart to upper layer. */ |
1742 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0, | |
1743 | new_asoc->c.sinit_num_ostreams, | |
1744 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 1745 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1746 | if (!ev) |
1747 | goto nomem_ev; | |
1748 | ||
df7deeb5 VY |
1749 | /* Update the content of current association. */ |
1750 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1751 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1752 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
1753 | return SCTP_DISPOSITION_CONSUME; | |
1754 | ||
1755 | nomem_ev: | |
1756 | sctp_chunk_free(repl); | |
1757 | nomem: | |
1758 | return SCTP_DISPOSITION_NOMEM; | |
1759 | } | |
1760 | ||
1761 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B') | |
1762 | * | |
1763 | * Section 5.2.4 | |
1764 | * B) In this case, both sides may be attempting to start an association | |
1765 | * at about the same time but the peer endpoint started its INIT | |
1766 | * after responding to the local endpoint's INIT | |
1767 | */ | |
1768 | /* This case represents an initialization collision. */ | |
1769 | static sctp_disposition_t sctp_sf_do_dupcook_b(const struct sctp_endpoint *ep, | |
1770 | const struct sctp_association *asoc, | |
1771 | struct sctp_chunk *chunk, | |
1772 | sctp_cmd_seq_t *commands, | |
1773 | struct sctp_association *new_asoc) | |
1774 | { | |
1775 | sctp_init_chunk_t *peer_init; | |
1da177e4 LT |
1776 | struct sctp_chunk *repl; |
1777 | ||
1778 | /* new_asoc is a brand-new association, so these are not yet | |
1779 | * side effects--it is safe to run them here. | |
1780 | */ | |
1781 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1782 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1783 | sctp_source(chunk), peer_init, | |
1784 | GFP_ATOMIC)) | |
1785 | goto nomem; | |
1786 | ||
1787 | /* Update the content of current association. */ | |
1788 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1789 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1790 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1791 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1792 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
1793 | ||
1794 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1795 | if (!repl) | |
1796 | goto nomem; | |
1797 | ||
1798 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1799 | |
1800 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1801 | * | |
1802 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
1803 | * send the Communication Up notification to the SCTP user | |
1804 | * upon reception of a valid COOKIE ECHO chunk. | |
07d93967 VY |
1805 | * |
1806 | * Sadly, this needs to be implemented as a side-effect, because | |
1807 | * we are not guaranteed to have set the association id of the real | |
1808 | * association and so these notifications need to be delayed until | |
1809 | * the association id is allocated. | |
1da177e4 | 1810 | */ |
1da177e4 | 1811 | |
07d93967 | 1812 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP)); |
1da177e4 LT |
1813 | |
1814 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1815 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 1816 | * delivers this notification to inform the application that of the |
0f3fffd8 | 1817 | * peers requested adaptation layer. |
07d93967 VY |
1818 | * |
1819 | * This also needs to be done as a side effect for the same reason as | |
1820 | * above. | |
1da177e4 | 1821 | */ |
07d93967 VY |
1822 | if (asoc->peer.adaptation_ind) |
1823 | sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL()); | |
1da177e4 LT |
1824 | |
1825 | return SCTP_DISPOSITION_CONSUME; | |
1826 | ||
1da177e4 LT |
1827 | nomem: |
1828 | return SCTP_DISPOSITION_NOMEM; | |
1829 | } | |
1830 | ||
1831 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C') | |
1832 | * | |
1833 | * Section 5.2.4 | |
1834 | * C) In this case, the local endpoint's cookie has arrived late. | |
1835 | * Before it arrived, the local endpoint sent an INIT and received an | |
1836 | * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag | |
1837 | * but a new tag of its own. | |
1838 | */ | |
1839 | /* This case represents an initialization collision. */ | |
1840 | static sctp_disposition_t sctp_sf_do_dupcook_c(const struct sctp_endpoint *ep, | |
1841 | const struct sctp_association *asoc, | |
1842 | struct sctp_chunk *chunk, | |
1843 | sctp_cmd_seq_t *commands, | |
1844 | struct sctp_association *new_asoc) | |
1845 | { | |
1846 | /* The cookie should be silently discarded. | |
1847 | * The endpoint SHOULD NOT change states and should leave | |
1848 | * any timers running. | |
1849 | */ | |
1850 | return SCTP_DISPOSITION_DISCARD; | |
1851 | } | |
1852 | ||
1853 | /* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D') | |
1854 | * | |
1855 | * Section 5.2.4 | |
1856 | * | |
1857 | * D) When both local and remote tags match the endpoint should always | |
1858 | * enter the ESTABLISHED state, if it has not already done so. | |
1859 | */ | |
1860 | /* This case represents an initialization collision. */ | |
1861 | static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep, | |
1862 | const struct sctp_association *asoc, | |
1863 | struct sctp_chunk *chunk, | |
1864 | sctp_cmd_seq_t *commands, | |
1865 | struct sctp_association *new_asoc) | |
1866 | { | |
df7deeb5 | 1867 | struct sctp_ulpevent *ev = NULL, *ai_ev = NULL; |
1da177e4 LT |
1868 | struct sctp_chunk *repl; |
1869 | ||
1870 | /* Clarification from Implementor's Guide: | |
1871 | * D) When both local and remote tags match the endpoint should | |
d808ad9a YH |
1872 | * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state. |
1873 | * It should stop any cookie timer that may be running and send | |
1874 | * a COOKIE ACK. | |
1da177e4 LT |
1875 | */ |
1876 | ||
1877 | /* Don't accidentally move back into established state. */ | |
1878 | if (asoc->state < SCTP_STATE_ESTABLISHED) { | |
1879 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1880 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
1881 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1882 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1883 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1884 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, | |
1885 | SCTP_NULL()); | |
1886 | ||
1887 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1888 | * | |
1889 | * D) IMPLEMENTATION NOTE: An implementation may choose | |
1890 | * to send the Communication Up notification to the | |
1891 | * SCTP user upon reception of a valid COOKIE | |
1892 | * ECHO chunk. | |
1893 | */ | |
df7deeb5 | 1894 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, |
1da177e4 | 1895 | SCTP_COMM_UP, 0, |
df7deeb5 VY |
1896 | asoc->c.sinit_num_ostreams, |
1897 | asoc->c.sinit_max_instreams, | |
9cbcbf4e | 1898 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1899 | if (!ev) |
1900 | goto nomem; | |
1da177e4 LT |
1901 | |
1902 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1903 | * When a peer sends a Adaptation Layer Indication parameter, |
1da177e4 | 1904 | * SCTP delivers this notification to inform the application |
0f3fffd8 | 1905 | * that of the peers requested adaptation layer. |
1da177e4 | 1906 | */ |
0f3fffd8 ISJ |
1907 | if (asoc->peer.adaptation_ind) { |
1908 | ai_ev = sctp_ulpevent_make_adaptation_indication(asoc, | |
1da177e4 | 1909 | GFP_ATOMIC); |
df7deeb5 | 1910 | if (!ai_ev) |
1da177e4 LT |
1911 | goto nomem; |
1912 | ||
1da177e4 LT |
1913 | } |
1914 | } | |
1da177e4 LT |
1915 | |
1916 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1917 | if (!repl) | |
1918 | goto nomem; | |
1919 | ||
2e3216cd VY |
1920 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
1921 | ||
df7deeb5 VY |
1922 | if (ev) |
1923 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1924 | SCTP_ULPEVENT(ev)); | |
1925 | if (ai_ev) | |
1926 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1927 | SCTP_ULPEVENT(ai_ev)); | |
1928 | ||
1da177e4 LT |
1929 | return SCTP_DISPOSITION_CONSUME; |
1930 | ||
1931 | nomem: | |
df7deeb5 VY |
1932 | if (ai_ev) |
1933 | sctp_ulpevent_free(ai_ev); | |
1da177e4 LT |
1934 | if (ev) |
1935 | sctp_ulpevent_free(ev); | |
1936 | return SCTP_DISPOSITION_NOMEM; | |
1937 | } | |
1938 | ||
1939 | /* | |
1940 | * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying | |
1941 | * chunk was retransmitted and then delayed in the network. | |
1942 | * | |
1943 | * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists | |
1944 | * | |
1945 | * Verification Tag: None. Do cookie validation. | |
1946 | * | |
1947 | * Inputs | |
1948 | * (endpoint, asoc, chunk) | |
1949 | * | |
1950 | * Outputs | |
1951 | * (asoc, reply_msg, msg_up, timers, counters) | |
1952 | * | |
1953 | * The return value is the disposition of the chunk. | |
1954 | */ | |
1955 | sctp_disposition_t sctp_sf_do_5_2_4_dupcook(const struct sctp_endpoint *ep, | |
1956 | const struct sctp_association *asoc, | |
1957 | const sctp_subtype_t type, | |
1958 | void *arg, | |
1959 | sctp_cmd_seq_t *commands) | |
1960 | { | |
1961 | sctp_disposition_t retval; | |
1962 | struct sctp_chunk *chunk = arg; | |
1963 | struct sctp_association *new_asoc; | |
1964 | int error = 0; | |
1965 | char action; | |
1966 | struct sctp_chunk *err_chk_p; | |
1967 | ||
1968 | /* Make sure that the chunk has a valid length from the protocol | |
1969 | * perspective. In this case check to make sure we have at least | |
1970 | * enough for the chunk header. Cookie length verification is | |
1971 | * done later. | |
1972 | */ | |
1973 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
1974 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1975 | commands); | |
1976 | ||
1977 | /* "Decode" the chunk. We have no optional parameters so we | |
1978 | * are in good shape. | |
1979 | */ | |
d808ad9a | 1980 | chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
1981 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
1982 | sizeof(sctp_chunkhdr_t))) | |
1983 | goto nomem; | |
1da177e4 LT |
1984 | |
1985 | /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie | |
1986 | * of a duplicate COOKIE ECHO match the Verification Tags of the | |
1987 | * current association, consider the State Cookie valid even if | |
1988 | * the lifespan is exceeded. | |
1989 | */ | |
1990 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
1991 | &err_chk_p); | |
1992 | ||
1993 | /* FIXME: | |
1994 | * If the re-build failed, what is the proper error path | |
1995 | * from here? | |
1996 | * | |
1997 | * [We should abort the association. --piggy] | |
1998 | */ | |
1999 | if (!new_asoc) { | |
2000 | /* FIXME: Several errors are possible. A bad cookie should | |
2001 | * be silently discarded, but think about logging it too. | |
2002 | */ | |
2003 | switch (error) { | |
2004 | case -SCTP_IERROR_NOMEM: | |
2005 | goto nomem; | |
2006 | ||
2007 | case -SCTP_IERROR_STALE_COOKIE: | |
2008 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
2009 | err_chk_p); | |
2010 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2011 | case -SCTP_IERROR_BAD_SIG: | |
2012 | default: | |
2013 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 2014 | } |
1da177e4 LT |
2015 | } |
2016 | ||
2017 | /* Compare the tie_tag in cookie with the verification tag of | |
2018 | * current association. | |
2019 | */ | |
2020 | action = sctp_tietags_compare(new_asoc, asoc); | |
2021 | ||
2022 | switch (action) { | |
2023 | case 'A': /* Association restart. */ | |
2024 | retval = sctp_sf_do_dupcook_a(ep, asoc, chunk, commands, | |
2025 | new_asoc); | |
2026 | break; | |
2027 | ||
2028 | case 'B': /* Collision case B. */ | |
2029 | retval = sctp_sf_do_dupcook_b(ep, asoc, chunk, commands, | |
2030 | new_asoc); | |
2031 | break; | |
2032 | ||
2033 | case 'C': /* Collision case C. */ | |
2034 | retval = sctp_sf_do_dupcook_c(ep, asoc, chunk, commands, | |
2035 | new_asoc); | |
2036 | break; | |
2037 | ||
2038 | case 'D': /* Collision case D. */ | |
2039 | retval = sctp_sf_do_dupcook_d(ep, asoc, chunk, commands, | |
2040 | new_asoc); | |
2041 | break; | |
2042 | ||
2043 | default: /* Discard packet for all others. */ | |
2044 | retval = sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2045 | break; | |
3ff50b79 | 2046 | } |
1da177e4 LT |
2047 | |
2048 | /* Delete the tempory new association. */ | |
2049 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
2050 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
2051 | ||
2052 | return retval; | |
2053 | ||
2054 | nomem: | |
2055 | return SCTP_DISPOSITION_NOMEM; | |
2056 | } | |
2057 | ||
2058 | /* | |
2059 | * Process an ABORT. (SHUTDOWN-PENDING state) | |
2060 | * | |
2061 | * See sctp_sf_do_9_1_abort(). | |
2062 | */ | |
2063 | sctp_disposition_t sctp_sf_shutdown_pending_abort( | |
2064 | const struct sctp_endpoint *ep, | |
2065 | const struct sctp_association *asoc, | |
2066 | const sctp_subtype_t type, | |
2067 | void *arg, | |
2068 | sctp_cmd_seq_t *commands) | |
2069 | { | |
2070 | struct sctp_chunk *chunk = arg; | |
2071 | ||
2072 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2073 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2074 | ||
2075 | /* Make sure that the ABORT chunk has a valid length. | |
2076 | * Since this is an ABORT chunk, we have to discard it | |
2077 | * because of the following text: | |
2078 | * RFC 2960, Section 3.3.7 | |
2079 | * If an endpoint receives an ABORT with a format error or for an | |
2080 | * association that doesn't exist, it MUST silently discard it. | |
2081 | * Becasue the length is "invalid", we can't really discard just | |
2082 | * as we do not know its true length. So, to be safe, discard the | |
2083 | * packet. | |
2084 | */ | |
2085 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2086 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2087 | ||
75205f47 VY |
2088 | /* ADD-IP: Special case for ABORT chunks |
2089 | * F4) One special consideration is that ABORT Chunks arriving | |
2090 | * destined to the IP address being deleted MUST be | |
2091 | * ignored (see Section 5.3.1 for further details). | |
2092 | */ | |
2093 | if (SCTP_ADDR_DEL == | |
2094 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2095 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2096 | ||
75205f47 | 2097 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); |
1da177e4 LT |
2098 | } |
2099 | ||
2100 | /* | |
2101 | * Process an ABORT. (SHUTDOWN-SENT state) | |
2102 | * | |
2103 | * See sctp_sf_do_9_1_abort(). | |
2104 | */ | |
2105 | sctp_disposition_t sctp_sf_shutdown_sent_abort(const struct sctp_endpoint *ep, | |
2106 | const struct sctp_association *asoc, | |
2107 | const sctp_subtype_t type, | |
2108 | void *arg, | |
2109 | sctp_cmd_seq_t *commands) | |
2110 | { | |
2111 | struct sctp_chunk *chunk = arg; | |
2112 | ||
2113 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2114 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2115 | ||
2116 | /* Make sure that the ABORT chunk has a valid length. | |
2117 | * Since this is an ABORT chunk, we have to discard it | |
2118 | * because of the following text: | |
2119 | * RFC 2960, Section 3.3.7 | |
2120 | * If an endpoint receives an ABORT with a format error or for an | |
2121 | * association that doesn't exist, it MUST silently discard it. | |
2122 | * Becasue the length is "invalid", we can't really discard just | |
2123 | * as we do not know its true length. So, to be safe, discard the | |
2124 | * packet. | |
2125 | */ | |
2126 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2127 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2128 | ||
75205f47 VY |
2129 | /* ADD-IP: Special case for ABORT chunks |
2130 | * F4) One special consideration is that ABORT Chunks arriving | |
2131 | * destined to the IP address being deleted MUST be | |
2132 | * ignored (see Section 5.3.1 for further details). | |
2133 | */ | |
2134 | if (SCTP_ADDR_DEL == | |
2135 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2136 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2137 | ||
1da177e4 LT |
2138 | /* Stop the T2-shutdown timer. */ |
2139 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2140 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2141 | ||
2142 | /* Stop the T5-shutdown guard timer. */ | |
2143 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2144 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2145 | ||
75205f47 | 2146 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); |
1da177e4 LT |
2147 | } |
2148 | ||
2149 | /* | |
2150 | * Process an ABORT. (SHUTDOWN-ACK-SENT state) | |
2151 | * | |
2152 | * See sctp_sf_do_9_1_abort(). | |
2153 | */ | |
2154 | sctp_disposition_t sctp_sf_shutdown_ack_sent_abort( | |
2155 | const struct sctp_endpoint *ep, | |
2156 | const struct sctp_association *asoc, | |
2157 | const sctp_subtype_t type, | |
2158 | void *arg, | |
2159 | sctp_cmd_seq_t *commands) | |
2160 | { | |
2161 | /* The same T2 timer, so we should be able to use | |
2162 | * common function with the SHUTDOWN-SENT state. | |
2163 | */ | |
2164 | return sctp_sf_shutdown_sent_abort(ep, asoc, type, arg, commands); | |
2165 | } | |
2166 | ||
2167 | /* | |
2168 | * Handle an Error received in COOKIE_ECHOED state. | |
2169 | * | |
2170 | * Only handle the error type of stale COOKIE Error, the other errors will | |
2171 | * be ignored. | |
2172 | * | |
2173 | * Inputs | |
2174 | * (endpoint, asoc, chunk) | |
2175 | * | |
2176 | * Outputs | |
2177 | * (asoc, reply_msg, msg_up, timers, counters) | |
2178 | * | |
2179 | * The return value is the disposition of the chunk. | |
2180 | */ | |
2181 | sctp_disposition_t sctp_sf_cookie_echoed_err(const struct sctp_endpoint *ep, | |
2182 | const struct sctp_association *asoc, | |
2183 | const sctp_subtype_t type, | |
2184 | void *arg, | |
2185 | sctp_cmd_seq_t *commands) | |
2186 | { | |
2187 | struct sctp_chunk *chunk = arg; | |
2188 | sctp_errhdr_t *err; | |
2189 | ||
2190 | if (!sctp_vtag_verify(chunk, asoc)) | |
2191 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2192 | ||
2193 | /* Make sure that the ERROR chunk has a valid length. | |
2194 | * The parameter walking depends on this as well. | |
2195 | */ | |
2196 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
2197 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2198 | commands); | |
2199 | ||
2200 | /* Process the error here */ | |
2201 | /* FUTURE FIXME: When PR-SCTP related and other optional | |
2202 | * parms are emitted, this will have to change to handle multiple | |
2203 | * errors. | |
2204 | */ | |
2205 | sctp_walk_errors(err, chunk->chunk_hdr) { | |
2206 | if (SCTP_ERROR_STALE_COOKIE == err->cause) | |
d808ad9a | 2207 | return sctp_sf_do_5_2_6_stale(ep, asoc, type, |
1da177e4 LT |
2208 | arg, commands); |
2209 | } | |
2210 | ||
2211 | /* It is possible to have malformed error causes, and that | |
2212 | * will cause us to end the walk early. However, since | |
2213 | * we are discarding the packet, there should be no adverse | |
2214 | * affects. | |
2215 | */ | |
2216 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2217 | } | |
2218 | ||
2219 | /* | |
2220 | * Handle a Stale COOKIE Error | |
2221 | * | |
2222 | * Section: 5.2.6 Handle Stale COOKIE Error | |
2223 | * If the association is in the COOKIE-ECHOED state, the endpoint may elect | |
2224 | * one of the following three alternatives. | |
2225 | * ... | |
2226 | * 3) Send a new INIT chunk to the endpoint, adding a Cookie | |
2227 | * Preservative parameter requesting an extension to the lifetime of | |
2228 | * the State Cookie. When calculating the time extension, an | |
2229 | * implementation SHOULD use the RTT information measured based on the | |
2230 | * previous COOKIE ECHO / ERROR exchange, and should add no more | |
2231 | * than 1 second beyond the measured RTT, due to long State Cookie | |
2232 | * lifetimes making the endpoint more subject to a replay attack. | |
2233 | * | |
2234 | * Verification Tag: Not explicit, but safe to ignore. | |
2235 | * | |
2236 | * Inputs | |
2237 | * (endpoint, asoc, chunk) | |
2238 | * | |
2239 | * Outputs | |
2240 | * (asoc, reply_msg, msg_up, timers, counters) | |
2241 | * | |
2242 | * The return value is the disposition of the chunk. | |
2243 | */ | |
2244 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, | |
2245 | const struct sctp_association *asoc, | |
2246 | const sctp_subtype_t type, | |
2247 | void *arg, | |
2248 | sctp_cmd_seq_t *commands) | |
2249 | { | |
2250 | struct sctp_chunk *chunk = arg; | |
2251 | time_t stale; | |
2252 | sctp_cookie_preserve_param_t bht; | |
2253 | sctp_errhdr_t *err; | |
2254 | struct sctp_chunk *reply; | |
2255 | struct sctp_bind_addr *bp; | |
3f7a87d2 | 2256 | int attempts = asoc->init_err_counter + 1; |
1da177e4 | 2257 | |
81845c21 | 2258 | if (attempts > asoc->max_init_attempts) { |
8de8c873 SS |
2259 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
2260 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 2261 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 2262 | SCTP_PERR(SCTP_ERROR_STALE_COOKIE)); |
1da177e4 LT |
2263 | return SCTP_DISPOSITION_DELETE_TCB; |
2264 | } | |
2265 | ||
2266 | err = (sctp_errhdr_t *)(chunk->skb->data); | |
2267 | ||
2268 | /* When calculating the time extension, an implementation | |
2269 | * SHOULD use the RTT information measured based on the | |
2270 | * previous COOKIE ECHO / ERROR exchange, and should add no | |
2271 | * more than 1 second beyond the measured RTT, due to long | |
2272 | * State Cookie lifetimes making the endpoint more subject to | |
2273 | * a replay attack. | |
2274 | * Measure of Staleness's unit is usec. (1/1000000 sec) | |
2275 | * Suggested Cookie Life-span Increment's unit is msec. | |
2276 | * (1/1000 sec) | |
2277 | * In general, if you use the suggested cookie life, the value | |
2278 | * found in the field of measure of staleness should be doubled | |
2279 | * to give ample time to retransmit the new cookie and thus | |
2280 | * yield a higher probability of success on the reattempt. | |
2281 | */ | |
34bcca28 | 2282 | stale = ntohl(*(__be32 *)((u8 *)err + sizeof(sctp_errhdr_t))); |
1da177e4 LT |
2283 | stale = (stale * 2) / 1000; |
2284 | ||
2285 | bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE; | |
2286 | bht.param_hdr.length = htons(sizeof(bht)); | |
2287 | bht.lifespan_increment = htonl(stale); | |
2288 | ||
2289 | /* Build that new INIT chunk. */ | |
2290 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; | |
2291 | reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht)); | |
2292 | if (!reply) | |
2293 | goto nomem; | |
2294 | ||
2295 | sctp_addto_chunk(reply, sizeof(bht), &bht); | |
2296 | ||
2297 | /* Clear peer's init_tag cached in assoc as we are sending a new INIT */ | |
2298 | sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL()); | |
2299 | ||
2300 | /* Stop pending T3-rtx and heartbeat timers */ | |
2301 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); | |
2302 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
2303 | ||
2304 | /* Delete non-primary peer ip addresses since we are transitioning | |
2305 | * back to the COOKIE-WAIT state | |
2306 | */ | |
2307 | sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL()); | |
2308 | ||
d808ad9a YH |
2309 | /* If we've sent any data bundled with COOKIE-ECHO we will need to |
2310 | * resend | |
1da177e4 | 2311 | */ |
b6157d8e | 2312 | sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN, |
1da177e4 LT |
2313 | SCTP_TRANSPORT(asoc->peer.primary_path)); |
2314 | ||
2315 | /* Cast away the const modifier, as we want to just | |
2316 | * rerun it through as a sideffect. | |
2317 | */ | |
3f7a87d2 | 2318 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL()); |
1da177e4 LT |
2319 | |
2320 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2321 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2322 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2323 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
2324 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
2325 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
2326 | ||
2327 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2328 | ||
2329 | return SCTP_DISPOSITION_CONSUME; | |
2330 | ||
2331 | nomem: | |
2332 | return SCTP_DISPOSITION_NOMEM; | |
2333 | } | |
2334 | ||
2335 | /* | |
2336 | * Process an ABORT. | |
2337 | * | |
2338 | * Section: 9.1 | |
2339 | * After checking the Verification Tag, the receiving endpoint shall | |
2340 | * remove the association from its record, and shall report the | |
2341 | * termination to its upper layer. | |
2342 | * | |
2343 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
2344 | * B) Rules for packet carrying ABORT: | |
2345 | * | |
2346 | * - The endpoint shall always fill in the Verification Tag field of the | |
2347 | * outbound packet with the destination endpoint's tag value if it | |
2348 | * is known. | |
2349 | * | |
2350 | * - If the ABORT is sent in response to an OOTB packet, the endpoint | |
2351 | * MUST follow the procedure described in Section 8.4. | |
2352 | * | |
2353 | * - The receiver MUST accept the packet if the Verification Tag | |
2354 | * matches either its own tag, OR the tag of its peer. Otherwise, the | |
2355 | * receiver MUST silently discard the packet and take no further | |
2356 | * action. | |
2357 | * | |
2358 | * Inputs | |
2359 | * (endpoint, asoc, chunk) | |
2360 | * | |
2361 | * Outputs | |
2362 | * (asoc, reply_msg, msg_up, timers, counters) | |
2363 | * | |
2364 | * The return value is the disposition of the chunk. | |
2365 | */ | |
2366 | sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, | |
2367 | const struct sctp_association *asoc, | |
2368 | const sctp_subtype_t type, | |
2369 | void *arg, | |
2370 | sctp_cmd_seq_t *commands) | |
2371 | { | |
2372 | struct sctp_chunk *chunk = arg; | |
1da177e4 LT |
2373 | |
2374 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2375 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2376 | ||
2377 | /* Make sure that the ABORT chunk has a valid length. | |
2378 | * Since this is an ABORT chunk, we have to discard it | |
2379 | * because of the following text: | |
2380 | * RFC 2960, Section 3.3.7 | |
2381 | * If an endpoint receives an ABORT with a format error or for an | |
2382 | * association that doesn't exist, it MUST silently discard it. | |
2383 | * Becasue the length is "invalid", we can't really discard just | |
2384 | * as we do not know its true length. So, to be safe, discard the | |
2385 | * packet. | |
2386 | */ | |
2387 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2388 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2389 | ||
75205f47 VY |
2390 | /* ADD-IP: Special case for ABORT chunks |
2391 | * F4) One special consideration is that ABORT Chunks arriving | |
2392 | * destined to the IP address being deleted MUST be | |
2393 | * ignored (see Section 5.3.1 for further details). | |
2394 | */ | |
2395 | if (SCTP_ADDR_DEL == | |
2396 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2397 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2398 | ||
2399 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); | |
2400 | } | |
2401 | ||
2402 | static sctp_disposition_t __sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, | |
2403 | const struct sctp_association *asoc, | |
2404 | const sctp_subtype_t type, | |
2405 | void *arg, | |
2406 | sctp_cmd_seq_t *commands) | |
2407 | { | |
2408 | struct sctp_chunk *chunk = arg; | |
2409 | unsigned len; | |
2410 | __be16 error = SCTP_ERROR_NO_ERROR; | |
2411 | ||
1da177e4 LT |
2412 | /* See if we have an error cause code in the chunk. */ |
2413 | len = ntohs(chunk->chunk_hdr->length); | |
2414 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2415 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2416 | ||
8de8c873 | 2417 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); |
d808ad9a | 2418 | /* ASSOC_FAILED will DELETE_TCB. */ |
5be291fe | 2419 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error)); |
1da177e4 LT |
2420 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
2421 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
2422 | ||
2423 | return SCTP_DISPOSITION_ABORT; | |
2424 | } | |
2425 | ||
2426 | /* | |
2427 | * Process an ABORT. (COOKIE-WAIT state) | |
2428 | * | |
2429 | * See sctp_sf_do_9_1_abort() above. | |
2430 | */ | |
2431 | sctp_disposition_t sctp_sf_cookie_wait_abort(const struct sctp_endpoint *ep, | |
2432 | const struct sctp_association *asoc, | |
2433 | const sctp_subtype_t type, | |
2434 | void *arg, | |
2435 | sctp_cmd_seq_t *commands) | |
2436 | { | |
2437 | struct sctp_chunk *chunk = arg; | |
2438 | unsigned len; | |
f94c0198 | 2439 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 LT |
2440 | |
2441 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2442 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2443 | ||
2444 | /* Make sure that the ABORT chunk has a valid length. | |
2445 | * Since this is an ABORT chunk, we have to discard it | |
2446 | * because of the following text: | |
2447 | * RFC 2960, Section 3.3.7 | |
2448 | * If an endpoint receives an ABORT with a format error or for an | |
2449 | * association that doesn't exist, it MUST silently discard it. | |
2450 | * Becasue the length is "invalid", we can't really discard just | |
2451 | * as we do not know its true length. So, to be safe, discard the | |
2452 | * packet. | |
2453 | */ | |
2454 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2455 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2456 | ||
2457 | /* See if we have an error cause code in the chunk. */ | |
2458 | len = ntohs(chunk->chunk_hdr->length); | |
2459 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2460 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2461 | ||
8de8c873 SS |
2462 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, asoc, |
2463 | chunk->transport); | |
1da177e4 LT |
2464 | } |
2465 | ||
2466 | /* | |
2467 | * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state) | |
2468 | */ | |
2469 | sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(const struct sctp_endpoint *ep, | |
2470 | const struct sctp_association *asoc, | |
2471 | const sctp_subtype_t type, | |
2472 | void *arg, | |
2473 | sctp_cmd_seq_t *commands) | |
2474 | { | |
8de8c873 SS |
2475 | return sctp_stop_t1_and_abort(commands, SCTP_ERROR_NO_ERROR, |
2476 | ENOPROTOOPT, asoc, | |
3f7a87d2 | 2477 | (struct sctp_transport *)arg); |
1da177e4 LT |
2478 | } |
2479 | ||
2480 | /* | |
2481 | * Process an ABORT. (COOKIE-ECHOED state) | |
2482 | */ | |
2483 | sctp_disposition_t sctp_sf_cookie_echoed_abort(const struct sctp_endpoint *ep, | |
2484 | const struct sctp_association *asoc, | |
2485 | const sctp_subtype_t type, | |
2486 | void *arg, | |
2487 | sctp_cmd_seq_t *commands) | |
2488 | { | |
2489 | /* There is a single T1 timer, so we should be able to use | |
2490 | * common function with the COOKIE-WAIT state. | |
2491 | */ | |
2492 | return sctp_sf_cookie_wait_abort(ep, asoc, type, arg, commands); | |
2493 | } | |
2494 | ||
2495 | /* | |
2496 | * Stop T1 timer and abort association with "INIT failed". | |
2497 | * | |
2498 | * This is common code called by several sctp_sf_*_abort() functions above. | |
2499 | */ | |
52c1da39 | 2500 | static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, |
f94c0198 | 2501 | __be16 error, int sk_err, |
3f7a87d2 FF |
2502 | const struct sctp_association *asoc, |
2503 | struct sctp_transport *transport) | |
1da177e4 | 2504 | { |
3f7a87d2 | 2505 | SCTP_DEBUG_PRINTK("ABORT received (INIT).\n"); |
1da177e4 LT |
2506 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
2507 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
2508 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
2509 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2510 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
8de8c873 | 2511 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); |
1da177e4 LT |
2512 | /* CMD_INIT_FAILED will DELETE_TCB. */ |
2513 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 2514 | SCTP_PERR(error)); |
3f7a87d2 | 2515 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
2516 | } |
2517 | ||
2518 | /* | |
2519 | * sctp_sf_do_9_2_shut | |
2520 | * | |
2521 | * Section: 9.2 | |
2522 | * Upon the reception of the SHUTDOWN, the peer endpoint shall | |
2523 | * - enter the SHUTDOWN-RECEIVED state, | |
2524 | * | |
2525 | * - stop accepting new data from its SCTP user | |
2526 | * | |
2527 | * - verify, by checking the Cumulative TSN Ack field of the chunk, | |
2528 | * that all its outstanding DATA chunks have been received by the | |
2529 | * SHUTDOWN sender. | |
2530 | * | |
2531 | * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT | |
2532 | * send a SHUTDOWN in response to a ULP request. And should discard | |
2533 | * subsequent SHUTDOWN chunks. | |
2534 | * | |
2535 | * If there are still outstanding DATA chunks left, the SHUTDOWN | |
2536 | * receiver shall continue to follow normal data transmission | |
2537 | * procedures defined in Section 6 until all outstanding DATA chunks | |
2538 | * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept | |
2539 | * new data from its SCTP user. | |
2540 | * | |
2541 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2542 | * | |
2543 | * Inputs | |
2544 | * (endpoint, asoc, chunk) | |
2545 | * | |
2546 | * Outputs | |
2547 | * (asoc, reply_msg, msg_up, timers, counters) | |
2548 | * | |
2549 | * The return value is the disposition of the chunk. | |
2550 | */ | |
2551 | sctp_disposition_t sctp_sf_do_9_2_shutdown(const struct sctp_endpoint *ep, | |
2552 | const struct sctp_association *asoc, | |
2553 | const sctp_subtype_t type, | |
2554 | void *arg, | |
2555 | sctp_cmd_seq_t *commands) | |
2556 | { | |
2557 | struct sctp_chunk *chunk = arg; | |
2558 | sctp_shutdownhdr_t *sdh; | |
2559 | sctp_disposition_t disposition; | |
2560 | struct sctp_ulpevent *ev; | |
df10eec4 | 2561 | __u32 ctsn; |
1da177e4 LT |
2562 | |
2563 | if (!sctp_vtag_verify(chunk, asoc)) | |
2564 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2565 | ||
2566 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2567 | if (!sctp_chunk_length_valid(chunk, | |
2568 | sizeof(struct sctp_shutdown_chunk_t))) | |
2569 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2570 | commands); | |
2571 | ||
2572 | /* Convert the elaborate header. */ | |
2573 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
2574 | skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t)); | |
2575 | chunk->subh.shutdown_hdr = sdh; | |
df10eec4 WY |
2576 | ctsn = ntohl(sdh->cum_tsn_ack); |
2577 | ||
a2f36eec WY |
2578 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { |
2579 | SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); | |
2580 | SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); | |
2581 | return SCTP_DISPOSITION_DISCARD; | |
2582 | } | |
2583 | ||
df10eec4 WY |
2584 | /* If Cumulative TSN Ack beyond the max tsn currently |
2585 | * send, terminating the association and respond to the | |
2586 | * sender with an ABORT. | |
2587 | */ | |
2588 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
2589 | return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); | |
1da177e4 | 2590 | |
eb0e0076 SS |
2591 | /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT |
2592 | * When a peer sends a SHUTDOWN, SCTP delivers this notification to | |
2593 | * inform the application that it should cease sending data. | |
2594 | */ | |
2595 | ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC); | |
2596 | if (!ev) { | |
2597 | disposition = SCTP_DISPOSITION_NOMEM; | |
d808ad9a | 2598 | goto out; |
eb0e0076 SS |
2599 | } |
2600 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
2601 | ||
1da177e4 LT |
2602 | /* Upon the reception of the SHUTDOWN, the peer endpoint shall |
2603 | * - enter the SHUTDOWN-RECEIVED state, | |
2604 | * - stop accepting new data from its SCTP user | |
2605 | * | |
2606 | * [This is implicit in the new state.] | |
2607 | */ | |
2608 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2609 | SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED)); | |
2610 | disposition = SCTP_DISPOSITION_CONSUME; | |
2611 | ||
2612 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
2613 | disposition = sctp_sf_do_9_2_shutdown_ack(ep, asoc, type, | |
2614 | arg, commands); | |
2615 | } | |
2616 | ||
2617 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
2618 | goto out; | |
2619 | ||
2620 | /* - verify, by checking the Cumulative TSN Ack field of the | |
2621 | * chunk, that all its outstanding DATA chunks have been | |
2622 | * received by the SHUTDOWN sender. | |
2623 | */ | |
2624 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2178eda8 | 2625 | SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack)); |
1da177e4 | 2626 | |
1da177e4 LT |
2627 | out: |
2628 | return disposition; | |
2629 | } | |
2630 | ||
2e3f92da WY |
2631 | /* |
2632 | * sctp_sf_do_9_2_shut_ctsn | |
2633 | * | |
2634 | * Once an endpoint has reached the SHUTDOWN-RECEIVED state, | |
2635 | * it MUST NOT send a SHUTDOWN in response to a ULP request. | |
2636 | * The Cumulative TSN Ack of the received SHUTDOWN chunk | |
2637 | * MUST be processed. | |
2638 | */ | |
2639 | sctp_disposition_t sctp_sf_do_9_2_shut_ctsn(const struct sctp_endpoint *ep, | |
2640 | const struct sctp_association *asoc, | |
2641 | const sctp_subtype_t type, | |
2642 | void *arg, | |
2643 | sctp_cmd_seq_t *commands) | |
2644 | { | |
2645 | struct sctp_chunk *chunk = arg; | |
2646 | sctp_shutdownhdr_t *sdh; | |
a2f36eec | 2647 | __u32 ctsn; |
2e3f92da WY |
2648 | |
2649 | if (!sctp_vtag_verify(chunk, asoc)) | |
2650 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2651 | ||
2652 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2653 | if (!sctp_chunk_length_valid(chunk, | |
2654 | sizeof(struct sctp_shutdown_chunk_t))) | |
2655 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2656 | commands); | |
2657 | ||
2658 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
a2f36eec WY |
2659 | ctsn = ntohl(sdh->cum_tsn_ack); |
2660 | ||
2661 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
2662 | SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); | |
2663 | SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); | |
2664 | return SCTP_DISPOSITION_DISCARD; | |
2665 | } | |
2e3f92da WY |
2666 | |
2667 | /* If Cumulative TSN Ack beyond the max tsn currently | |
2668 | * send, terminating the association and respond to the | |
2669 | * sender with an ABORT. | |
2670 | */ | |
a2f36eec | 2671 | if (!TSN_lt(ctsn, asoc->next_tsn)) |
2e3f92da WY |
2672 | return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); |
2673 | ||
2674 | /* verify, by checking the Cumulative TSN Ack field of the | |
2675 | * chunk, that all its outstanding DATA chunks have been | |
2676 | * received by the SHUTDOWN sender. | |
2677 | */ | |
2678 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2679 | SCTP_BE32(sdh->cum_tsn_ack)); | |
2680 | ||
2681 | return SCTP_DISPOSITION_CONSUME; | |
2682 | } | |
2683 | ||
1da177e4 LT |
2684 | /* RFC 2960 9.2 |
2685 | * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk | |
2686 | * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination | |
2687 | * transport addresses (either in the IP addresses or in the INIT chunk) | |
2688 | * that belong to this association, it should discard the INIT chunk and | |
2689 | * retransmit the SHUTDOWN ACK chunk. | |
2690 | */ | |
2691 | sctp_disposition_t sctp_sf_do_9_2_reshutack(const struct sctp_endpoint *ep, | |
2692 | const struct sctp_association *asoc, | |
2693 | const sctp_subtype_t type, | |
2694 | void *arg, | |
2695 | sctp_cmd_seq_t *commands) | |
2696 | { | |
2697 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
2698 | struct sctp_chunk *reply; | |
2699 | ||
ece25dfa VY |
2700 | /* Make sure that the chunk has a valid length */ |
2701 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
2702 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2703 | commands); | |
2704 | ||
1da177e4 LT |
2705 | /* Since we are not going to really process this INIT, there |
2706 | * is no point in verifying chunk boundries. Just generate | |
2707 | * the SHUTDOWN ACK. | |
2708 | */ | |
2709 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
2710 | if (NULL == reply) | |
2711 | goto nomem; | |
2712 | ||
2713 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
2714 | * the T2-SHUTDOWN timer. | |
2715 | */ | |
2716 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
2717 | ||
2718 | /* and restart the T2-shutdown timer. */ | |
2719 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2720 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2721 | ||
2722 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2723 | ||
2724 | return SCTP_DISPOSITION_CONSUME; | |
2725 | nomem: | |
2726 | return SCTP_DISPOSITION_NOMEM; | |
2727 | } | |
2728 | ||
2729 | /* | |
2730 | * sctp_sf_do_ecn_cwr | |
2731 | * | |
2732 | * Section: Appendix A: Explicit Congestion Notification | |
2733 | * | |
2734 | * CWR: | |
2735 | * | |
2736 | * RFC 2481 details a specific bit for a sender to send in the header of | |
2737 | * its next outbound TCP segment to indicate to its peer that it has | |
2738 | * reduced its congestion window. This is termed the CWR bit. For | |
2739 | * SCTP the same indication is made by including the CWR chunk. | |
2740 | * This chunk contains one data element, i.e. the TSN number that | |
2741 | * was sent in the ECNE chunk. This element represents the lowest | |
2742 | * TSN number in the datagram that was originally marked with the | |
2743 | * CE bit. | |
2744 | * | |
2745 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2746 | * Inputs | |
2747 | * (endpoint, asoc, chunk) | |
2748 | * | |
2749 | * Outputs | |
2750 | * (asoc, reply_msg, msg_up, timers, counters) | |
2751 | * | |
2752 | * The return value is the disposition of the chunk. | |
2753 | */ | |
2754 | sctp_disposition_t sctp_sf_do_ecn_cwr(const struct sctp_endpoint *ep, | |
2755 | const struct sctp_association *asoc, | |
2756 | const sctp_subtype_t type, | |
2757 | void *arg, | |
2758 | sctp_cmd_seq_t *commands) | |
2759 | { | |
2760 | sctp_cwrhdr_t *cwr; | |
2761 | struct sctp_chunk *chunk = arg; | |
34bcca28 | 2762 | u32 lowest_tsn; |
1da177e4 LT |
2763 | |
2764 | if (!sctp_vtag_verify(chunk, asoc)) | |
2765 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2766 | ||
2767 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2768 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2769 | commands); | |
d808ad9a | 2770 | |
1da177e4 LT |
2771 | cwr = (sctp_cwrhdr_t *) chunk->skb->data; |
2772 | skb_pull(chunk->skb, sizeof(sctp_cwrhdr_t)); | |
2773 | ||
34bcca28 | 2774 | lowest_tsn = ntohl(cwr->lowest_tsn); |
1da177e4 LT |
2775 | |
2776 | /* Does this CWR ack the last sent congestion notification? */ | |
34bcca28 | 2777 | if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) { |
1da177e4 LT |
2778 | /* Stop sending ECNE. */ |
2779 | sctp_add_cmd_sf(commands, | |
2780 | SCTP_CMD_ECN_CWR, | |
34bcca28 | 2781 | SCTP_U32(lowest_tsn)); |
1da177e4 LT |
2782 | } |
2783 | return SCTP_DISPOSITION_CONSUME; | |
2784 | } | |
2785 | ||
2786 | /* | |
2787 | * sctp_sf_do_ecne | |
2788 | * | |
2789 | * Section: Appendix A: Explicit Congestion Notification | |
2790 | * | |
2791 | * ECN-Echo | |
2792 | * | |
2793 | * RFC 2481 details a specific bit for a receiver to send back in its | |
2794 | * TCP acknowledgements to notify the sender of the Congestion | |
2795 | * Experienced (CE) bit having arrived from the network. For SCTP this | |
2796 | * same indication is made by including the ECNE chunk. This chunk | |
2797 | * contains one data element, i.e. the lowest TSN associated with the IP | |
2798 | * datagram marked with the CE bit..... | |
2799 | * | |
2800 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2801 | * Inputs | |
2802 | * (endpoint, asoc, chunk) | |
2803 | * | |
2804 | * Outputs | |
2805 | * (asoc, reply_msg, msg_up, timers, counters) | |
2806 | * | |
2807 | * The return value is the disposition of the chunk. | |
2808 | */ | |
2809 | sctp_disposition_t sctp_sf_do_ecne(const struct sctp_endpoint *ep, | |
2810 | const struct sctp_association *asoc, | |
2811 | const sctp_subtype_t type, | |
2812 | void *arg, | |
2813 | sctp_cmd_seq_t *commands) | |
2814 | { | |
2815 | sctp_ecnehdr_t *ecne; | |
2816 | struct sctp_chunk *chunk = arg; | |
2817 | ||
2818 | if (!sctp_vtag_verify(chunk, asoc)) | |
2819 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2820 | ||
2821 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2822 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2823 | commands); | |
2824 | ||
2825 | ecne = (sctp_ecnehdr_t *) chunk->skb->data; | |
2826 | skb_pull(chunk->skb, sizeof(sctp_ecnehdr_t)); | |
2827 | ||
2828 | /* If this is a newer ECNE than the last CWR packet we sent out */ | |
2829 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE, | |
2830 | SCTP_U32(ntohl(ecne->lowest_tsn))); | |
2831 | ||
2832 | return SCTP_DISPOSITION_CONSUME; | |
2833 | } | |
2834 | ||
2835 | /* | |
2836 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
2837 | * | |
2838 | * The SCTP endpoint MUST always acknowledge the reception of each valid | |
2839 | * DATA chunk. | |
2840 | * | |
2841 | * The guidelines on delayed acknowledgement algorithm specified in | |
2842 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
2843 | * acknowledgement SHOULD be generated for at least every second packet | |
2844 | * (not every second DATA chunk) received, and SHOULD be generated within | |
2845 | * 200 ms of the arrival of any unacknowledged DATA chunk. In some | |
2846 | * situations it may be beneficial for an SCTP transmitter to be more | |
2847 | * conservative than the algorithms detailed in this document allow. | |
2848 | * However, an SCTP transmitter MUST NOT be more aggressive than the | |
2849 | * following algorithms allow. | |
2850 | * | |
2851 | * A SCTP receiver MUST NOT generate more than one SACK for every | |
2852 | * incoming packet, other than to update the offered window as the | |
2853 | * receiving application consumes new data. | |
2854 | * | |
2855 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2856 | * | |
2857 | * Inputs | |
2858 | * (endpoint, asoc, chunk) | |
2859 | * | |
2860 | * Outputs | |
2861 | * (asoc, reply_msg, msg_up, timers, counters) | |
2862 | * | |
2863 | * The return value is the disposition of the chunk. | |
2864 | */ | |
2865 | sctp_disposition_t sctp_sf_eat_data_6_2(const struct sctp_endpoint *ep, | |
2866 | const struct sctp_association *asoc, | |
2867 | const sctp_subtype_t type, | |
2868 | void *arg, | |
2869 | sctp_cmd_seq_t *commands) | |
2870 | { | |
2871 | struct sctp_chunk *chunk = arg; | |
6dc7694f | 2872 | sctp_arg_t force = SCTP_NOFORCE(); |
1da177e4 LT |
2873 | int error; |
2874 | ||
2875 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2876 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2877 | SCTP_NULL()); | |
2878 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 2879 | } |
1da177e4 LT |
2880 | |
2881 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
2882 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2883 | commands); | |
2884 | ||
2885 | error = sctp_eat_data(asoc, chunk, commands ); | |
2886 | switch (error) { | |
2887 | case SCTP_IERROR_NO_ERROR: | |
2888 | break; | |
2889 | case SCTP_IERROR_HIGH_TSN: | |
2890 | case SCTP_IERROR_BAD_STREAM: | |
ac0b0462 | 2891 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2892 | goto discard_noforce; |
2893 | case SCTP_IERROR_DUP_TSN: | |
2894 | case SCTP_IERROR_IGNORE_TSN: | |
ac0b0462 | 2895 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2896 | goto discard_force; |
2897 | case SCTP_IERROR_NO_DATA: | |
2898 | goto consume; | |
f1751c57 VY |
2899 | case SCTP_IERROR_PROTO_VIOLATION: |
2900 | return sctp_sf_abort_violation(ep, asoc, chunk, commands, | |
2901 | (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t)); | |
1da177e4 LT |
2902 | default: |
2903 | BUG(); | |
2904 | } | |
2905 | ||
6dc7694f WY |
2906 | if (chunk->chunk_hdr->flags & SCTP_DATA_SACK_IMM) |
2907 | force = SCTP_FORCE(); | |
2908 | ||
1da177e4 LT |
2909 | if (asoc->autoclose) { |
2910 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2911 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
2912 | } | |
2913 | ||
2914 | /* If this is the last chunk in a packet, we need to count it | |
2915 | * toward sack generation. Note that we need to SACK every | |
2916 | * OTHER packet containing data chunks, EVEN IF WE DISCARD | |
2917 | * THEM. We elect to NOT generate SACK's if the chunk fails | |
2918 | * the verification tag test. | |
2919 | * | |
2920 | * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2921 | * | |
2922 | * The SCTP endpoint MUST always acknowledge the reception of | |
2923 | * each valid DATA chunk. | |
2924 | * | |
2925 | * The guidelines on delayed acknowledgement algorithm | |
2926 | * specified in Section 4.2 of [RFC2581] SHOULD be followed. | |
2927 | * Specifically, an acknowledgement SHOULD be generated for at | |
2928 | * least every second packet (not every second DATA chunk) | |
2929 | * received, and SHOULD be generated within 200 ms of the | |
2930 | * arrival of any unacknowledged DATA chunk. In some | |
2931 | * situations it may be beneficial for an SCTP transmitter to | |
2932 | * be more conservative than the algorithms detailed in this | |
2933 | * document allow. However, an SCTP transmitter MUST NOT be | |
2934 | * more aggressive than the following algorithms allow. | |
2935 | */ | |
52ccb8e9 | 2936 | if (chunk->end_of_packet) |
6dc7694f | 2937 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 2938 | |
1da177e4 LT |
2939 | return SCTP_DISPOSITION_CONSUME; |
2940 | ||
2941 | discard_force: | |
2942 | /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2943 | * | |
2944 | * When a packet arrives with duplicate DATA chunk(s) and with | |
2945 | * no new DATA chunk(s), the endpoint MUST immediately send a | |
2946 | * SACK with no delay. If a packet arrives with duplicate | |
2947 | * DATA chunk(s) bundled with new DATA chunks, the endpoint | |
2948 | * MAY immediately send a SACK. Normally receipt of duplicate | |
2949 | * DATA chunks will occur when the original SACK chunk was lost | |
2950 | * and the peer's RTO has expired. The duplicate TSN number(s) | |
2951 | * SHOULD be reported in the SACK as duplicate. | |
2952 | */ | |
2953 | /* In our case, we split the MAY SACK advice up whether or not | |
2954 | * the last chunk is a duplicate.' | |
2955 | */ | |
2956 | if (chunk->end_of_packet) | |
2957 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
2958 | return SCTP_DISPOSITION_DISCARD; | |
2959 | ||
2960 | discard_noforce: | |
52ccb8e9 | 2961 | if (chunk->end_of_packet) |
6dc7694f | 2962 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, force); |
1da177e4 | 2963 | |
1da177e4 LT |
2964 | return SCTP_DISPOSITION_DISCARD; |
2965 | consume: | |
2966 | return SCTP_DISPOSITION_CONSUME; | |
d808ad9a | 2967 | |
1da177e4 LT |
2968 | } |
2969 | ||
2970 | /* | |
2971 | * sctp_sf_eat_data_fast_4_4 | |
2972 | * | |
2973 | * Section: 4 (4) | |
2974 | * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received | |
2975 | * DATA chunks without delay. | |
2976 | * | |
2977 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2978 | * Inputs | |
2979 | * (endpoint, asoc, chunk) | |
2980 | * | |
2981 | * Outputs | |
2982 | * (asoc, reply_msg, msg_up, timers, counters) | |
2983 | * | |
2984 | * The return value is the disposition of the chunk. | |
2985 | */ | |
2986 | sctp_disposition_t sctp_sf_eat_data_fast_4_4(const struct sctp_endpoint *ep, | |
2987 | const struct sctp_association *asoc, | |
2988 | const sctp_subtype_t type, | |
2989 | void *arg, | |
2990 | sctp_cmd_seq_t *commands) | |
2991 | { | |
2992 | struct sctp_chunk *chunk = arg; | |
2993 | int error; | |
2994 | ||
2995 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2996 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2997 | SCTP_NULL()); | |
2998 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2999 | } | |
3000 | ||
3001 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
3002 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3003 | commands); | |
3004 | ||
3005 | error = sctp_eat_data(asoc, chunk, commands ); | |
3006 | switch (error) { | |
3007 | case SCTP_IERROR_NO_ERROR: | |
3008 | case SCTP_IERROR_HIGH_TSN: | |
3009 | case SCTP_IERROR_DUP_TSN: | |
3010 | case SCTP_IERROR_IGNORE_TSN: | |
3011 | case SCTP_IERROR_BAD_STREAM: | |
3012 | break; | |
3013 | case SCTP_IERROR_NO_DATA: | |
3014 | goto consume; | |
f1751c57 VY |
3015 | case SCTP_IERROR_PROTO_VIOLATION: |
3016 | return sctp_sf_abort_violation(ep, asoc, chunk, commands, | |
3017 | (u8 *)chunk->subh.data_hdr, sizeof(sctp_datahdr_t)); | |
1da177e4 LT |
3018 | default: |
3019 | BUG(); | |
3020 | } | |
3021 | ||
3022 | /* Go a head and force a SACK, since we are shutting down. */ | |
3023 | ||
3024 | /* Implementor's Guide. | |
3025 | * | |
3026 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3027 | * respond to each received packet containing one or more DATA chunk(s) | |
3028 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3029 | */ | |
3030 | if (chunk->end_of_packet) { | |
3031 | /* We must delay the chunk creation since the cumulative | |
3032 | * TSN has not been updated yet. | |
3033 | */ | |
3034 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3035 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3036 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3037 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3038 | } | |
3039 | ||
3040 | consume: | |
3041 | return SCTP_DISPOSITION_CONSUME; | |
3042 | } | |
3043 | ||
3044 | /* | |
3045 | * Section: 6.2 Processing a Received SACK | |
3046 | * D) Any time a SACK arrives, the endpoint performs the following: | |
3047 | * | |
3048 | * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point, | |
3049 | * then drop the SACK. Since Cumulative TSN Ack is monotonically | |
3050 | * increasing, a SACK whose Cumulative TSN Ack is less than the | |
3051 | * Cumulative TSN Ack Point indicates an out-of-order SACK. | |
3052 | * | |
3053 | * ii) Set rwnd equal to the newly received a_rwnd minus the number | |
3054 | * of bytes still outstanding after processing the Cumulative TSN Ack | |
3055 | * and the Gap Ack Blocks. | |
3056 | * | |
3057 | * iii) If the SACK is missing a TSN that was previously | |
3058 | * acknowledged via a Gap Ack Block (e.g., the data receiver | |
3059 | * reneged on the data), then mark the corresponding DATA chunk | |
3060 | * as available for retransmit: Mark it as missing for fast | |
3061 | * retransmit as described in Section 7.2.4 and if no retransmit | |
3062 | * timer is running for the destination address to which the DATA | |
3063 | * chunk was originally transmitted, then T3-rtx is started for | |
3064 | * that destination address. | |
3065 | * | |
3066 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3067 | * | |
3068 | * Inputs | |
3069 | * (endpoint, asoc, chunk) | |
3070 | * | |
3071 | * Outputs | |
3072 | * (asoc, reply_msg, msg_up, timers, counters) | |
3073 | * | |
3074 | * The return value is the disposition of the chunk. | |
3075 | */ | |
3076 | sctp_disposition_t sctp_sf_eat_sack_6_2(const struct sctp_endpoint *ep, | |
3077 | const struct sctp_association *asoc, | |
3078 | const sctp_subtype_t type, | |
3079 | void *arg, | |
3080 | sctp_cmd_seq_t *commands) | |
3081 | { | |
3082 | struct sctp_chunk *chunk = arg; | |
3083 | sctp_sackhdr_t *sackh; | |
3084 | __u32 ctsn; | |
3085 | ||
3086 | if (!sctp_vtag_verify(chunk, asoc)) | |
3087 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3088 | ||
3089 | /* Make sure that the SACK chunk has a valid length. */ | |
3090 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t))) | |
3091 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3092 | commands); | |
3093 | ||
3094 | /* Pull the SACK chunk from the data buffer */ | |
3095 | sackh = sctp_sm_pull_sack(chunk); | |
3096 | /* Was this a bogus SACK? */ | |
3097 | if (!sackh) | |
3098 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3099 | chunk->subh.sack_hdr = sackh; | |
3100 | ctsn = ntohl(sackh->cum_tsn_ack); | |
3101 | ||
3102 | /* i) If Cumulative TSN Ack is less than the Cumulative TSN | |
3103 | * Ack Point, then drop the SACK. Since Cumulative TSN | |
3104 | * Ack is monotonically increasing, a SACK whose | |
3105 | * Cumulative TSN Ack is less than the Cumulative TSN Ack | |
3106 | * Point indicates an out-of-order SACK. | |
3107 | */ | |
3108 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
3109 | SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); | |
3110 | SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); | |
3111 | return SCTP_DISPOSITION_DISCARD; | |
3112 | } | |
3113 | ||
aecedeab WY |
3114 | /* If Cumulative TSN Ack beyond the max tsn currently |
3115 | * send, terminating the association and respond to the | |
3116 | * sender with an ABORT. | |
3117 | */ | |
3118 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
3119 | return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); | |
3120 | ||
1da177e4 LT |
3121 | /* Return this SACK for further processing. */ |
3122 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_SACKH(sackh)); | |
3123 | ||
3124 | /* Note: We do the rest of the work on the PROCESS_SACK | |
3125 | * sideeffect. | |
3126 | */ | |
3127 | return SCTP_DISPOSITION_CONSUME; | |
3128 | } | |
3129 | ||
3130 | /* | |
3131 | * Generate an ABORT in response to a packet. | |
3132 | * | |
047a2428 | 3133 | * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41 |
1da177e4 | 3134 | * |
047a2428 JF |
3135 | * 8) The receiver should respond to the sender of the OOTB packet with |
3136 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3137 | * MUST fill in the Verification Tag field of the outbound packet | |
3138 | * with the value found in the Verification Tag field of the OOTB | |
3139 | * packet and set the T-bit in the Chunk Flags to indicate that the | |
3140 | * Verification Tag is reflected. After sending this ABORT, the | |
3141 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3142 | * no further action. | |
1da177e4 LT |
3143 | * |
3144 | * Verification Tag: | |
3145 | * | |
3146 | * The return value is the disposition of the chunk. | |
3147 | */ | |
ece25dfa | 3148 | static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, |
1da177e4 LT |
3149 | const struct sctp_association *asoc, |
3150 | const sctp_subtype_t type, | |
3151 | void *arg, | |
3152 | sctp_cmd_seq_t *commands) | |
3153 | { | |
3154 | struct sctp_packet *packet = NULL; | |
3155 | struct sctp_chunk *chunk = arg; | |
3156 | struct sctp_chunk *abort; | |
3157 | ||
3158 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
3159 | ||
3160 | if (packet) { | |
3161 | /* Make an ABORT. The T bit will be set if the asoc | |
3162 | * is NULL. | |
3163 | */ | |
d808ad9a | 3164 | abort = sctp_make_abort(asoc, chunk, 0); |
1da177e4 LT |
3165 | if (!abort) { |
3166 | sctp_ootb_pkt_free(packet); | |
3167 | return SCTP_DISPOSITION_NOMEM; | |
3168 | } | |
3169 | ||
047a2428 JF |
3170 | /* Reflect vtag if T-Bit is set */ |
3171 | if (sctp_test_T_bit(abort)) | |
3172 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3173 | ||
1da177e4 LT |
3174 | /* Set the skb to the belonging sock for accounting. */ |
3175 | abort->skb->sk = ep->base.sk; | |
3176 | ||
3177 | sctp_packet_append_chunk(packet, abort); | |
3178 | ||
3179 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3180 | SCTP_PACKET(packet)); | |
3181 | ||
3182 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
3183 | ||
d3f25968 | 3184 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); |
1da177e4 LT |
3185 | return SCTP_DISPOSITION_CONSUME; |
3186 | } | |
3187 | ||
3188 | return SCTP_DISPOSITION_NOMEM; | |
3189 | } | |
3190 | ||
3191 | /* | |
3192 | * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR | |
3193 | * event as ULP notification for each cause included in the chunk. | |
3194 | * | |
3195 | * API 5.3.1.3 - SCTP_REMOTE_ERROR | |
3196 | * | |
3197 | * The return value is the disposition of the chunk. | |
3198 | */ | |
3199 | sctp_disposition_t sctp_sf_operr_notify(const struct sctp_endpoint *ep, | |
3200 | const struct sctp_association *asoc, | |
3201 | const sctp_subtype_t type, | |
3202 | void *arg, | |
3203 | sctp_cmd_seq_t *commands) | |
3204 | { | |
3205 | struct sctp_chunk *chunk = arg; | |
1da177e4 LT |
3206 | |
3207 | if (!sctp_vtag_verify(chunk, asoc)) | |
3208 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3209 | ||
3210 | /* Make sure that the ERROR chunk has a valid length. */ | |
3211 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
3212 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3213 | commands); | |
3214 | ||
3df26787 WY |
3215 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR, |
3216 | SCTP_CHUNK(chunk)); | |
1da177e4 | 3217 | |
1da177e4 | 3218 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3219 | } |
3220 | ||
3221 | /* | |
3222 | * Process an inbound SHUTDOWN ACK. | |
3223 | * | |
3224 | * From Section 9.2: | |
3225 | * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3226 | * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its | |
3227 | * peer, and remove all record of the association. | |
3228 | * | |
3229 | * The return value is the disposition. | |
3230 | */ | |
3231 | sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep, | |
3232 | const struct sctp_association *asoc, | |
3233 | const sctp_subtype_t type, | |
3234 | void *arg, | |
3235 | sctp_cmd_seq_t *commands) | |
3236 | { | |
3237 | struct sctp_chunk *chunk = arg; | |
3238 | struct sctp_chunk *reply; | |
3239 | struct sctp_ulpevent *ev; | |
3240 | ||
3241 | if (!sctp_vtag_verify(chunk, asoc)) | |
3242 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3243 | ||
3244 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3245 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3246 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3247 | commands); | |
1da177e4 LT |
3248 | /* 10.2 H) SHUTDOWN COMPLETE notification |
3249 | * | |
3250 | * When SCTP completes the shutdown procedures (section 9.2) this | |
3251 | * notification is passed to the upper layer. | |
3252 | */ | |
3253 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 3254 | 0, 0, 0, NULL, GFP_ATOMIC); |
1da177e4 LT |
3255 | if (!ev) |
3256 | goto nomem; | |
3257 | ||
df7deeb5 VY |
3258 | /* ...send a SHUTDOWN COMPLETE chunk to its peer, */ |
3259 | reply = sctp_make_shutdown_complete(asoc, chunk); | |
3260 | if (!reply) | |
3261 | goto nomem_chunk; | |
3262 | ||
3263 | /* Do all the commands now (after allocation), so that we | |
3264 | * have consistent state if memory allocation failes | |
3265 | */ | |
1da177e4 LT |
3266 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
3267 | ||
3268 | /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3269 | * stop the T2-shutdown timer, | |
3270 | */ | |
3271 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3272 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3273 | ||
3274 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3275 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
3276 | ||
1da177e4 LT |
3277 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
3278 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
3279 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
3280 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3281 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
3282 | ||
3283 | /* ...and remove all record of the association. */ | |
3284 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
3285 | return SCTP_DISPOSITION_DELETE_TCB; | |
3286 | ||
df7deeb5 VY |
3287 | nomem_chunk: |
3288 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
3289 | nomem: |
3290 | return SCTP_DISPOSITION_NOMEM; | |
3291 | } | |
3292 | ||
3293 | /* | |
047a2428 JF |
3294 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41. |
3295 | * | |
1da177e4 LT |
3296 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
3297 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. | |
3298 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3299 | * packet must fill in the Verification Tag field of the outbound | |
3300 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
047a2428 JF |
3301 | * set the T-bit in the Chunk Flags to indicate that the Verification |
3302 | * Tag is reflected. | |
1da177e4 LT |
3303 | * |
3304 | * 8) The receiver should respond to the sender of the OOTB packet with | |
3305 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3306 | * MUST fill in the Verification Tag field of the outbound packet | |
3307 | * with the value found in the Verification Tag field of the OOTB | |
047a2428 JF |
3308 | * packet and set the T-bit in the Chunk Flags to indicate that the |
3309 | * Verification Tag is reflected. After sending this ABORT, the | |
3310 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3311 | * no further action. | |
1da177e4 LT |
3312 | */ |
3313 | sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep, | |
3314 | const struct sctp_association *asoc, | |
3315 | const sctp_subtype_t type, | |
3316 | void *arg, | |
3317 | sctp_cmd_seq_t *commands) | |
3318 | { | |
3319 | struct sctp_chunk *chunk = arg; | |
3320 | struct sk_buff *skb = chunk->skb; | |
3321 | sctp_chunkhdr_t *ch; | |
3322 | __u8 *ch_end; | |
3323 | int ootb_shut_ack = 0; | |
3324 | ||
3325 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
3326 | ||
3327 | ch = (sctp_chunkhdr_t *) chunk->chunk_hdr; | |
3328 | do { | |
ece25dfa | 3329 | /* Report violation if the chunk is less then minimal */ |
1da177e4 | 3330 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
ece25dfa VY |
3331 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, |
3332 | commands); | |
1da177e4 | 3333 | |
ece25dfa VY |
3334 | /* Now that we know we at least have a chunk header, |
3335 | * do things that are type appropriate. | |
3336 | */ | |
1da177e4 LT |
3337 | if (SCTP_CID_SHUTDOWN_ACK == ch->type) |
3338 | ootb_shut_ack = 1; | |
3339 | ||
3340 | /* RFC 2960, Section 3.3.7 | |
3341 | * Moreover, under any circumstances, an endpoint that | |
3342 | * receives an ABORT MUST NOT respond to that ABORT by | |
3343 | * sending an ABORT of its own. | |
3344 | */ | |
3345 | if (SCTP_CID_ABORT == ch->type) | |
3346 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 3347 | |
ece25dfa VY |
3348 | /* Report violation if chunk len overflows */ |
3349 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); | |
3350 | if (ch_end > skb_tail_pointer(skb)) | |
3351 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3352 | commands); | |
3353 | ||
1da177e4 | 3354 | ch = (sctp_chunkhdr_t *) ch_end; |
27a884dc | 3355 | } while (ch_end < skb_tail_pointer(skb)); |
1da177e4 LT |
3356 | |
3357 | if (ootb_shut_ack) | |
d3f25968 | 3358 | return sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands); |
1da177e4 | 3359 | else |
d3f25968 | 3360 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
1da177e4 LT |
3361 | } |
3362 | ||
3363 | /* | |
3364 | * Handle an "Out of the blue" SHUTDOWN ACK. | |
3365 | * | |
047a2428 JF |
3366 | * Section: 8.4 5, sctpimpguide 2.41. |
3367 | * | |
1da177e4 | 3368 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
047a2428 JF |
3369 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. |
3370 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3371 | * packet must fill in the Verification Tag field of the outbound | |
3372 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
3373 | * set the T-bit in the Chunk Flags to indicate that the Verification | |
3374 | * Tag is reflected. | |
1da177e4 LT |
3375 | * |
3376 | * Inputs | |
3377 | * (endpoint, asoc, type, arg, commands) | |
3378 | * | |
3379 | * Outputs | |
3380 | * (sctp_disposition_t) | |
3381 | * | |
3382 | * The return value is the disposition of the chunk. | |
3383 | */ | |
3384 | static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, | |
3385 | const struct sctp_association *asoc, | |
3386 | const sctp_subtype_t type, | |
3387 | void *arg, | |
3388 | sctp_cmd_seq_t *commands) | |
3389 | { | |
3390 | struct sctp_packet *packet = NULL; | |
3391 | struct sctp_chunk *chunk = arg; | |
3392 | struct sctp_chunk *shut; | |
3393 | ||
3394 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
3395 | ||
3396 | if (packet) { | |
3397 | /* Make an SHUTDOWN_COMPLETE. | |
d808ad9a YH |
3398 | * The T bit will be set if the asoc is NULL. |
3399 | */ | |
1da177e4 LT |
3400 | shut = sctp_make_shutdown_complete(asoc, chunk); |
3401 | if (!shut) { | |
3402 | sctp_ootb_pkt_free(packet); | |
3403 | return SCTP_DISPOSITION_NOMEM; | |
3404 | } | |
3405 | ||
047a2428 JF |
3406 | /* Reflect vtag if T-Bit is set */ |
3407 | if (sctp_test_T_bit(shut)) | |
3408 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3409 | ||
1da177e4 LT |
3410 | /* Set the skb to the belonging sock for accounting. */ |
3411 | shut->skb->sk = ep->base.sk; | |
3412 | ||
3413 | sctp_packet_append_chunk(packet, shut); | |
3414 | ||
3415 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3416 | SCTP_PACKET(packet)); | |
3417 | ||
3418 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
3419 | ||
3420 | /* If the chunk length is invalid, we don't want to process | |
3421 | * the reset of the packet. | |
3422 | */ | |
3423 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3424 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3425 | ||
d3f25968 VY |
3426 | /* We need to discard the rest of the packet to prevent |
3427 | * potential bomming attacks from additional bundled chunks. | |
3428 | * This is documented in SCTP Threats ID. | |
3429 | */ | |
3430 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1da177e4 LT |
3431 | } |
3432 | ||
3433 | return SCTP_DISPOSITION_NOMEM; | |
3434 | } | |
3435 | ||
3436 | /* | |
3437 | * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state. | |
3438 | * | |
3439 | * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK | |
3440 | * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the | |
3441 | * procedures in section 8.4 SHOULD be followed, in other words it | |
3442 | * should be treated as an Out Of The Blue packet. | |
3443 | * [This means that we do NOT check the Verification Tag on these | |
3444 | * chunks. --piggy ] | |
3445 | * | |
3446 | */ | |
3447 | sctp_disposition_t sctp_sf_do_8_5_1_E_sa(const struct sctp_endpoint *ep, | |
3448 | const struct sctp_association *asoc, | |
3449 | const sctp_subtype_t type, | |
3450 | void *arg, | |
3451 | sctp_cmd_seq_t *commands) | |
3452 | { | |
ece25dfa VY |
3453 | struct sctp_chunk *chunk = arg; |
3454 | ||
3455 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3456 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3457 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3458 | commands); | |
3459 | ||
1da177e4 LT |
3460 | /* Although we do have an association in this case, it corresponds |
3461 | * to a restarted association. So the packet is treated as an OOTB | |
3462 | * packet and the state function that handles OOTB SHUTDOWN_ACK is | |
3463 | * called with a NULL association. | |
3464 | */ | |
8190f89d WY |
3465 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); |
3466 | ||
1da177e4 LT |
3467 | return sctp_sf_shut_8_4_5(ep, NULL, type, arg, commands); |
3468 | } | |
3469 | ||
3470 | /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */ | |
3471 | sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep, | |
3472 | const struct sctp_association *asoc, | |
3473 | const sctp_subtype_t type, void *arg, | |
3474 | sctp_cmd_seq_t *commands) | |
3475 | { | |
3476 | struct sctp_chunk *chunk = arg; | |
3477 | struct sctp_chunk *asconf_ack = NULL; | |
6f4c618d | 3478 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 | 3479 | sctp_addiphdr_t *hdr; |
6f4c618d | 3480 | union sctp_addr_param *addr_param; |
1da177e4 | 3481 | __u32 serial; |
6f4c618d | 3482 | int length; |
1da177e4 LT |
3483 | |
3484 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3485 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3486 | SCTP_NULL()); | |
3487 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3488 | } | |
3489 | ||
6afd2e83 VY |
3490 | /* ADD-IP: Section 4.1.1 |
3491 | * This chunk MUST be sent in an authenticated way by using | |
3492 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3493 | * is received unauthenticated it MUST be silently discarded as | |
3494 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3495 | */ | |
3496 | if (!sctp_addip_noauth && !chunk->auth) | |
3497 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
3498 | ||
1da177e4 LT |
3499 | /* Make sure that the ASCONF ADDIP chunk has a valid length. */ |
3500 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t))) | |
3501 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3502 | commands); | |
3503 | ||
3504 | hdr = (sctp_addiphdr_t *)chunk->skb->data; | |
3505 | serial = ntohl(hdr->serial); | |
3506 | ||
6f4c618d WY |
3507 | addr_param = (union sctp_addr_param *)hdr->params; |
3508 | length = ntohs(addr_param->p.length); | |
3509 | if (length < sizeof(sctp_paramhdr_t)) | |
ba016670 | 3510 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
6f4c618d WY |
3511 | (void *)addr_param, commands); |
3512 | ||
3513 | /* Verify the ASCONF chunk before processing it. */ | |
3514 | if (!sctp_verify_asconf(asoc, | |
a08de64d VY |
3515 | (sctp_paramhdr_t *)((void *)addr_param + length), |
3516 | (void *)chunk->chunk_end, | |
3517 | &err_param)) | |
ba016670 WY |
3518 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
3519 | (void *)err_param, commands); | |
6f4c618d | 3520 | |
a08de64d | 3521 | /* ADDIP 5.2 E1) Compare the value of the serial number to the value |
1da177e4 | 3522 | * the endpoint stored in a new association variable |
d808ad9a | 3523 | * 'Peer-Serial-Number'. |
1da177e4 LT |
3524 | */ |
3525 | if (serial == asoc->peer.addip_serial + 1) { | |
a08de64d VY |
3526 | /* If this is the first instance of ASCONF in the packet, |
3527 | * we can clean our old ASCONF-ACKs. | |
3528 | */ | |
3529 | if (!chunk->has_asconf) | |
3530 | sctp_assoc_clean_asconf_ack_cache(asoc); | |
3531 | ||
3532 | /* ADDIP 5.2 E4) When the Sequence Number matches the next one | |
3533 | * expected, process the ASCONF as described below and after | |
3534 | * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to | |
3535 | * the response packet and cache a copy of it (in the event it | |
3536 | * later needs to be retransmitted). | |
3537 | * | |
3538 | * Essentially, do V1-V5. | |
1da177e4 LT |
3539 | */ |
3540 | asconf_ack = sctp_process_asconf((struct sctp_association *) | |
3541 | asoc, chunk); | |
3542 | if (!asconf_ack) | |
3543 | return SCTP_DISPOSITION_NOMEM; | |
a08de64d VY |
3544 | } else if (serial < asoc->peer.addip_serial + 1) { |
3545 | /* ADDIP 5.2 E2) | |
3546 | * If the value found in the Sequence Number is less than the | |
3547 | * ('Peer- Sequence-Number' + 1), simply skip to the next | |
3548 | * ASCONF, and include in the outbound response packet | |
3549 | * any previously cached ASCONF-ACK response that was | |
3550 | * sent and saved that matches the Sequence Number of the | |
3551 | * ASCONF. Note: It is possible that no cached ASCONF-ACK | |
3552 | * Chunk exists. This will occur when an older ASCONF | |
3553 | * arrives out of order. In such a case, the receiver | |
3554 | * should skip the ASCONF Chunk and not include ASCONF-ACK | |
3555 | * Chunk for that chunk. | |
1da177e4 | 3556 | */ |
a08de64d VY |
3557 | asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial); |
3558 | if (!asconf_ack) | |
1da177e4 | 3559 | return SCTP_DISPOSITION_DISCARD; |
31b02e15 VY |
3560 | |
3561 | /* Reset the transport so that we select the correct one | |
3562 | * this time around. This is to make sure that we don't | |
3563 | * accidentally use a stale transport that's been removed. | |
3564 | */ | |
3565 | asconf_ack->transport = NULL; | |
1da177e4 | 3566 | } else { |
a08de64d | 3567 | /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since |
1da177e4 | 3568 | * it must be either a stale packet or from an attacker. |
d808ad9a | 3569 | */ |
1da177e4 LT |
3570 | return SCTP_DISPOSITION_DISCARD; |
3571 | } | |
3572 | ||
a08de64d VY |
3573 | /* ADDIP 5.2 E6) The destination address of the SCTP packet |
3574 | * containing the ASCONF-ACK Chunks MUST be the source address of | |
3575 | * the SCTP packet that held the ASCONF Chunks. | |
3576 | * | |
3577 | * To do this properly, we'll set the destination address of the chunk | |
3578 | * and at the transmit time, will try look up the transport to use. | |
3579 | * Since ASCONFs may be bundled, the correct transport may not be | |
94e2bd68 | 3580 | * created until we process the entire packet, thus this workaround. |
1da177e4 | 3581 | */ |
a08de64d | 3582 | asconf_ack->dest = chunk->source; |
1da177e4 | 3583 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack)); |
d808ad9a | 3584 | |
1da177e4 LT |
3585 | return SCTP_DISPOSITION_CONSUME; |
3586 | } | |
3587 | ||
3588 | /* | |
3589 | * ADDIP Section 4.3 General rules for address manipulation | |
3590 | * When building TLV parameters for the ASCONF Chunk that will add or | |
3591 | * delete IP addresses the D0 to D13 rules should be applied: | |
3592 | */ | |
3593 | sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, | |
3594 | const struct sctp_association *asoc, | |
d808ad9a | 3595 | const sctp_subtype_t type, void *arg, |
1da177e4 LT |
3596 | sctp_cmd_seq_t *commands) |
3597 | { | |
3598 | struct sctp_chunk *asconf_ack = arg; | |
3599 | struct sctp_chunk *last_asconf = asoc->addip_last_asconf; | |
3600 | struct sctp_chunk *abort; | |
6f4c618d | 3601 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 LT |
3602 | sctp_addiphdr_t *addip_hdr; |
3603 | __u32 sent_serial, rcvd_serial; | |
3604 | ||
3605 | if (!sctp_vtag_verify(asconf_ack, asoc)) { | |
3606 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3607 | SCTP_NULL()); | |
3608 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3609 | } | |
3610 | ||
6afd2e83 VY |
3611 | /* ADD-IP, Section 4.1.2: |
3612 | * This chunk MUST be sent in an authenticated way by using | |
3613 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3614 | * is received unauthenticated it MUST be silently discarded as | |
3615 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3616 | */ | |
3617 | if (!sctp_addip_noauth && !asconf_ack->auth) | |
3618 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
3619 | ||
1da177e4 LT |
3620 | /* Make sure that the ADDIP chunk has a valid length. */ |
3621 | if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t))) | |
3622 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3623 | commands); | |
3624 | ||
3625 | addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data; | |
3626 | rcvd_serial = ntohl(addip_hdr->serial); | |
3627 | ||
6f4c618d WY |
3628 | /* Verify the ASCONF-ACK chunk before processing it. */ |
3629 | if (!sctp_verify_asconf(asoc, | |
3630 | (sctp_paramhdr_t *)addip_hdr->params, | |
3631 | (void *)asconf_ack->chunk_end, | |
3632 | &err_param)) | |
ba016670 WY |
3633 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
3634 | (void *)err_param, commands); | |
6f4c618d | 3635 | |
1da177e4 LT |
3636 | if (last_asconf) { |
3637 | addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr; | |
3638 | sent_serial = ntohl(addip_hdr->serial); | |
3639 | } else { | |
3640 | sent_serial = asoc->addip_serial - 1; | |
3641 | } | |
3642 | ||
3643 | /* D0) If an endpoint receives an ASCONF-ACK that is greater than or | |
3644 | * equal to the next serial number to be used but no ASCONF chunk is | |
3645 | * outstanding the endpoint MUST ABORT the association. Note that a | |
3646 | * sequence number is greater than if it is no more than 2^^31-1 | |
3647 | * larger than the current sequence number (using serial arithmetic). | |
3648 | */ | |
3649 | if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) && | |
3650 | !(asoc->addip_last_asconf)) { | |
3651 | abort = sctp_make_abort(asoc, asconf_ack, | |
3652 | sizeof(sctp_errhdr_t)); | |
3653 | if (abort) { | |
00f1c2df | 3654 | sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0); |
1da177e4 LT |
3655 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3656 | SCTP_CHUNK(abort)); | |
3657 | } | |
3658 | /* We are going to ABORT, so we might as well stop | |
3659 | * processing the rest of the chunks in the packet. | |
3660 | */ | |
3661 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3662 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3663 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3664 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3665 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3666 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3667 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3668 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3669 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3670 | return SCTP_DISPOSITION_ABORT; | |
3671 | } | |
3672 | ||
3673 | if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) { | |
3674 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3675 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3676 | ||
3677 | if (!sctp_process_asconf_ack((struct sctp_association *)asoc, | |
3678 | asconf_ack)) | |
3679 | return SCTP_DISPOSITION_CONSUME; | |
3680 | ||
3681 | abort = sctp_make_abort(asoc, asconf_ack, | |
3682 | sizeof(sctp_errhdr_t)); | |
3683 | if (abort) { | |
00f1c2df | 3684 | sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0); |
1da177e4 LT |
3685 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3686 | SCTP_CHUNK(abort)); | |
3687 | } | |
3688 | /* We are going to ABORT, so we might as well stop | |
3689 | * processing the rest of the chunks in the packet. | |
3690 | */ | |
3691 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3692 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3693 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3694 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3695 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3696 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3697 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3698 | return SCTP_DISPOSITION_ABORT; | |
3699 | } | |
3700 | ||
3701 | return SCTP_DISPOSITION_DISCARD; | |
3702 | } | |
3703 | ||
3704 | /* | |
3705 | * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP | |
3706 | * | |
3707 | * When a FORWARD TSN chunk arrives, the data receiver MUST first update | |
3708 | * its cumulative TSN point to the value carried in the FORWARD TSN | |
3709 | * chunk, and then MUST further advance its cumulative TSN point locally | |
3710 | * if possible. | |
3711 | * After the above processing, the data receiver MUST stop reporting any | |
3712 | * missing TSNs earlier than or equal to the new cumulative TSN point. | |
3713 | * | |
3714 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3715 | * | |
3716 | * The return value is the disposition of the chunk. | |
3717 | */ | |
3718 | sctp_disposition_t sctp_sf_eat_fwd_tsn(const struct sctp_endpoint *ep, | |
3719 | const struct sctp_association *asoc, | |
3720 | const sctp_subtype_t type, | |
3721 | void *arg, | |
3722 | sctp_cmd_seq_t *commands) | |
3723 | { | |
3724 | struct sctp_chunk *chunk = arg; | |
3725 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
9fcb95a1 | 3726 | struct sctp_fwdtsn_skip *skip; |
1da177e4 LT |
3727 | __u16 len; |
3728 | __u32 tsn; | |
3729 | ||
3730 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3731 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3732 | SCTP_NULL()); | |
3733 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3734 | } | |
3735 | ||
3736 | /* Make sure that the FORWARD_TSN chunk has valid length. */ | |
3737 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3738 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3739 | commands); | |
3740 | ||
3741 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3742 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3743 | len = ntohs(chunk->chunk_hdr->length); | |
3744 | len -= sizeof(struct sctp_chunkhdr); | |
3745 | skb_pull(chunk->skb, len); | |
3746 | ||
3747 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
0dc47877 | 3748 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __func__, tsn); |
1da177e4 LT |
3749 | |
3750 | /* The TSN is too high--silently discard the chunk and count on it | |
3751 | * getting retransmitted later. | |
3752 | */ | |
3753 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3754 | goto discard_noforce; | |
3755 | ||
9fcb95a1 WY |
3756 | /* Silently discard the chunk if stream-id is not valid */ |
3757 | sctp_walk_fwdtsn(skip, chunk) { | |
3758 | if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams) | |
3759 | goto discard_noforce; | |
3760 | } | |
3761 | ||
1da177e4 LT |
3762 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
3763 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3764 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3765 | SCTP_CHUNK(chunk)); |
d808ad9a | 3766 | |
1da177e4 LT |
3767 | /* Count this as receiving DATA. */ |
3768 | if (asoc->autoclose) { | |
3769 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3770 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
3771 | } | |
d808ad9a | 3772 | |
1da177e4 | 3773 | /* FIXME: For now send a SACK, but DATA processing may |
d808ad9a | 3774 | * send another. |
1da177e4 LT |
3775 | */ |
3776 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); | |
1da177e4 LT |
3777 | |
3778 | return SCTP_DISPOSITION_CONSUME; | |
3779 | ||
3780 | discard_noforce: | |
3781 | return SCTP_DISPOSITION_DISCARD; | |
3782 | } | |
3783 | ||
3784 | sctp_disposition_t sctp_sf_eat_fwd_tsn_fast( | |
3785 | const struct sctp_endpoint *ep, | |
3786 | const struct sctp_association *asoc, | |
3787 | const sctp_subtype_t type, | |
3788 | void *arg, | |
3789 | sctp_cmd_seq_t *commands) | |
3790 | { | |
3791 | struct sctp_chunk *chunk = arg; | |
3792 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
9fcb95a1 | 3793 | struct sctp_fwdtsn_skip *skip; |
1da177e4 LT |
3794 | __u16 len; |
3795 | __u32 tsn; | |
3796 | ||
3797 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3798 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3799 | SCTP_NULL()); | |
3800 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3801 | } | |
3802 | ||
3803 | /* Make sure that the FORWARD_TSN chunk has a valid length. */ | |
3804 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3805 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3806 | commands); | |
3807 | ||
3808 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3809 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3810 | len = ntohs(chunk->chunk_hdr->length); | |
3811 | len -= sizeof(struct sctp_chunkhdr); | |
3812 | skb_pull(chunk->skb, len); | |
3813 | ||
3814 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
0dc47877 | 3815 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __func__, tsn); |
1da177e4 LT |
3816 | |
3817 | /* The TSN is too high--silently discard the chunk and count on it | |
3818 | * getting retransmitted later. | |
3819 | */ | |
3820 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3821 | goto gen_shutdown; | |
3822 | ||
9fcb95a1 WY |
3823 | /* Silently discard the chunk if stream-id is not valid */ |
3824 | sctp_walk_fwdtsn(skip, chunk) { | |
3825 | if (ntohs(skip->stream) >= asoc->c.sinit_max_instreams) | |
3826 | goto gen_shutdown; | |
3827 | } | |
3828 | ||
1da177e4 LT |
3829 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); |
3830 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3831 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3832 | SCTP_CHUNK(chunk)); |
d808ad9a | 3833 | |
1da177e4 LT |
3834 | /* Go a head and force a SACK, since we are shutting down. */ |
3835 | gen_shutdown: | |
3836 | /* Implementor's Guide. | |
3837 | * | |
3838 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3839 | * respond to each received packet containing one or more DATA chunk(s) | |
3840 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3841 | */ | |
3842 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3843 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3844 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3845 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3846 | ||
d808ad9a | 3847 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3848 | } |
3849 | ||
bbd0d598 VY |
3850 | /* |
3851 | * SCTP-AUTH Section 6.3 Receving authenticated chukns | |
3852 | * | |
3853 | * The receiver MUST use the HMAC algorithm indicated in the HMAC | |
3854 | * Identifier field. If this algorithm was not specified by the | |
3855 | * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk | |
3856 | * during association setup, the AUTH chunk and all chunks after it MUST | |
3857 | * be discarded and an ERROR chunk SHOULD be sent with the error cause | |
3858 | * defined in Section 4.1. | |
3859 | * | |
3860 | * If an endpoint with no shared key receives a Shared Key Identifier | |
3861 | * other than 0, it MUST silently discard all authenticated chunks. If | |
3862 | * the endpoint has at least one endpoint pair shared key for the peer, | |
3863 | * it MUST use the key specified by the Shared Key Identifier if a | |
3864 | * key has been configured for that Shared Key Identifier. If no | |
3865 | * endpoint pair shared key has been configured for that Shared Key | |
3866 | * Identifier, all authenticated chunks MUST be silently discarded. | |
3867 | * | |
3868 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3869 | * | |
3870 | * The return value is the disposition of the chunk. | |
3871 | */ | |
3872 | static sctp_ierror_t sctp_sf_authenticate(const struct sctp_endpoint *ep, | |
3873 | const struct sctp_association *asoc, | |
3874 | const sctp_subtype_t type, | |
3875 | struct sctp_chunk *chunk) | |
3876 | { | |
3877 | struct sctp_authhdr *auth_hdr; | |
3878 | struct sctp_hmac *hmac; | |
3879 | unsigned int sig_len; | |
3880 | __u16 key_id; | |
3881 | __u8 *save_digest; | |
3882 | __u8 *digest; | |
3883 | ||
3884 | /* Pull in the auth header, so we can do some more verification */ | |
3885 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
3886 | chunk->subh.auth_hdr = auth_hdr; | |
3887 | skb_pull(chunk->skb, sizeof(struct sctp_authhdr)); | |
3888 | ||
3889 | /* Make sure that we suport the HMAC algorithm from the auth | |
3890 | * chunk. | |
3891 | */ | |
3892 | if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id)) | |
3893 | return SCTP_IERROR_AUTH_BAD_HMAC; | |
3894 | ||
3895 | /* Make sure that the provided shared key identifier has been | |
3896 | * configured | |
3897 | */ | |
3898 | key_id = ntohs(auth_hdr->shkey_id); | |
3899 | if (key_id != asoc->active_key_id && !sctp_auth_get_shkey(asoc, key_id)) | |
3900 | return SCTP_IERROR_AUTH_BAD_KEYID; | |
3901 | ||
3902 | ||
3903 | /* Make sure that the length of the signature matches what | |
3904 | * we expect. | |
3905 | */ | |
3906 | sig_len = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_auth_chunk_t); | |
3907 | hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id)); | |
3908 | if (sig_len != hmac->hmac_len) | |
3909 | return SCTP_IERROR_PROTO_VIOLATION; | |
3910 | ||
3911 | /* Now that we've done validation checks, we can compute and | |
3912 | * verify the hmac. The steps involved are: | |
3913 | * 1. Save the digest from the chunk. | |
3914 | * 2. Zero out the digest in the chunk. | |
3915 | * 3. Compute the new digest | |
3916 | * 4. Compare saved and new digests. | |
3917 | */ | |
3918 | digest = auth_hdr->hmac; | |
3919 | skb_pull(chunk->skb, sig_len); | |
3920 | ||
3921 | save_digest = kmemdup(digest, sig_len, GFP_ATOMIC); | |
3922 | if (!save_digest) | |
3923 | goto nomem; | |
3924 | ||
3925 | memset(digest, 0, sig_len); | |
3926 | ||
3927 | sctp_auth_calculate_hmac(asoc, chunk->skb, | |
3928 | (struct sctp_auth_chunk *)chunk->chunk_hdr, | |
3929 | GFP_ATOMIC); | |
3930 | ||
3931 | /* Discard the packet if the digests do not match */ | |
3932 | if (memcmp(save_digest, digest, sig_len)) { | |
3933 | kfree(save_digest); | |
3934 | return SCTP_IERROR_BAD_SIG; | |
3935 | } | |
3936 | ||
3937 | kfree(save_digest); | |
3938 | chunk->auth = 1; | |
3939 | ||
3940 | return SCTP_IERROR_NO_ERROR; | |
3941 | nomem: | |
3942 | return SCTP_IERROR_NOMEM; | |
3943 | } | |
3944 | ||
3945 | sctp_disposition_t sctp_sf_eat_auth(const struct sctp_endpoint *ep, | |
3946 | const struct sctp_association *asoc, | |
3947 | const sctp_subtype_t type, | |
3948 | void *arg, | |
3949 | sctp_cmd_seq_t *commands) | |
3950 | { | |
3951 | struct sctp_authhdr *auth_hdr; | |
3952 | struct sctp_chunk *chunk = arg; | |
3953 | struct sctp_chunk *err_chunk; | |
3954 | sctp_ierror_t error; | |
3955 | ||
d2f19fa1 WY |
3956 | /* Make sure that the peer has AUTH capable */ |
3957 | if (!asoc->peer.auth_capable) | |
3958 | return sctp_sf_unk_chunk(ep, asoc, type, arg, commands); | |
3959 | ||
bbd0d598 VY |
3960 | if (!sctp_vtag_verify(chunk, asoc)) { |
3961 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3962 | SCTP_NULL()); | |
3963 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3964 | } | |
3965 | ||
3966 | /* Make sure that the AUTH chunk has valid length. */ | |
3967 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk))) | |
3968 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3969 | commands); | |
3970 | ||
3971 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
3972 | error = sctp_sf_authenticate(ep, asoc, type, chunk); | |
3973 | switch (error) { | |
3974 | case SCTP_IERROR_AUTH_BAD_HMAC: | |
3975 | /* Generate the ERROR chunk and discard the rest | |
3976 | * of the packet | |
3977 | */ | |
3978 | err_chunk = sctp_make_op_error(asoc, chunk, | |
3979 | SCTP_ERROR_UNSUP_HMAC, | |
3980 | &auth_hdr->hmac_id, | |
6383cfb3 | 3981 | sizeof(__u16), 0); |
bbd0d598 VY |
3982 | if (err_chunk) { |
3983 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3984 | SCTP_CHUNK(err_chunk)); | |
3985 | } | |
3986 | /* Fall Through */ | |
3987 | case SCTP_IERROR_AUTH_BAD_KEYID: | |
3988 | case SCTP_IERROR_BAD_SIG: | |
3989 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3990 | break; | |
3991 | case SCTP_IERROR_PROTO_VIOLATION: | |
3992 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3993 | commands); | |
3994 | break; | |
3995 | case SCTP_IERROR_NOMEM: | |
3996 | return SCTP_DISPOSITION_NOMEM; | |
3997 | default: | |
3998 | break; | |
3999 | } | |
4000 | ||
65b07e5d VY |
4001 | if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) { |
4002 | struct sctp_ulpevent *ev; | |
4003 | ||
4004 | ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id), | |
4005 | SCTP_AUTH_NEWKEY, GFP_ATOMIC); | |
4006 | ||
4007 | if (!ev) | |
4008 | return -ENOMEM; | |
4009 | ||
4010 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
4011 | SCTP_ULPEVENT(ev)); | |
4012 | } | |
4013 | ||
bbd0d598 VY |
4014 | return SCTP_DISPOSITION_CONSUME; |
4015 | } | |
4016 | ||
1da177e4 LT |
4017 | /* |
4018 | * Process an unknown chunk. | |
4019 | * | |
4020 | * Section: 3.2. Also, 2.1 in the implementor's guide. | |
4021 | * | |
4022 | * Chunk Types are encoded such that the highest-order two bits specify | |
4023 | * the action that must be taken if the processing endpoint does not | |
4024 | * recognize the Chunk Type. | |
4025 | * | |
4026 | * 00 - Stop processing this SCTP packet and discard it, do not process | |
4027 | * any further chunks within it. | |
4028 | * | |
4029 | * 01 - Stop processing this SCTP packet and discard it, do not process | |
4030 | * any further chunks within it, and report the unrecognized | |
4031 | * chunk in an 'Unrecognized Chunk Type'. | |
4032 | * | |
4033 | * 10 - Skip this chunk and continue processing. | |
4034 | * | |
4035 | * 11 - Skip this chunk and continue processing, but report in an ERROR | |
4036 | * Chunk using the 'Unrecognized Chunk Type' cause of error. | |
4037 | * | |
4038 | * The return value is the disposition of the chunk. | |
4039 | */ | |
4040 | sctp_disposition_t sctp_sf_unk_chunk(const struct sctp_endpoint *ep, | |
4041 | const struct sctp_association *asoc, | |
4042 | const sctp_subtype_t type, | |
4043 | void *arg, | |
4044 | sctp_cmd_seq_t *commands) | |
4045 | { | |
4046 | struct sctp_chunk *unk_chunk = arg; | |
4047 | struct sctp_chunk *err_chunk; | |
4048 | sctp_chunkhdr_t *hdr; | |
4049 | ||
4050 | SCTP_DEBUG_PRINTK("Processing the unknown chunk id %d.\n", type.chunk); | |
4051 | ||
4052 | if (!sctp_vtag_verify(unk_chunk, asoc)) | |
4053 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
4054 | ||
4055 | /* Make sure that the chunk has a valid length. | |
4056 | * Since we don't know the chunk type, we use a general | |
4057 | * chunkhdr structure to make a comparison. | |
4058 | */ | |
4059 | if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t))) | |
4060 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4061 | commands); | |
4062 | ||
4063 | switch (type.chunk & SCTP_CID_ACTION_MASK) { | |
4064 | case SCTP_CID_ACTION_DISCARD: | |
4065 | /* Discard the packet. */ | |
4066 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
4067 | break; | |
4068 | case SCTP_CID_ACTION_DISCARD_ERR: | |
1da177e4 LT |
4069 | /* Generate an ERROR chunk as response. */ |
4070 | hdr = unk_chunk->chunk_hdr; | |
4071 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4072 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
6383cfb3 VY |
4073 | WORD_ROUND(ntohs(hdr->length)), |
4074 | 0); | |
1da177e4 LT |
4075 | if (err_chunk) { |
4076 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4077 | SCTP_CHUNK(err_chunk)); | |
4078 | } | |
2e3216cd VY |
4079 | |
4080 | /* Discard the packet. */ | |
4081 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1da177e4 LT |
4082 | return SCTP_DISPOSITION_CONSUME; |
4083 | break; | |
4084 | case SCTP_CID_ACTION_SKIP: | |
4085 | /* Skip the chunk. */ | |
4086 | return SCTP_DISPOSITION_DISCARD; | |
4087 | break; | |
4088 | case SCTP_CID_ACTION_SKIP_ERR: | |
4089 | /* Generate an ERROR chunk as response. */ | |
4090 | hdr = unk_chunk->chunk_hdr; | |
4091 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
4092 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
6383cfb3 VY |
4093 | WORD_ROUND(ntohs(hdr->length)), |
4094 | 0); | |
1da177e4 LT |
4095 | if (err_chunk) { |
4096 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
4097 | SCTP_CHUNK(err_chunk)); | |
4098 | } | |
4099 | /* Skip the chunk. */ | |
4100 | return SCTP_DISPOSITION_CONSUME; | |
4101 | break; | |
4102 | default: | |
4103 | break; | |
4104 | } | |
4105 | ||
4106 | return SCTP_DISPOSITION_DISCARD; | |
4107 | } | |
4108 | ||
4109 | /* | |
4110 | * Discard the chunk. | |
4111 | * | |
4112 | * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2 | |
4113 | * [Too numerous to mention...] | |
4114 | * Verification Tag: No verification needed. | |
4115 | * Inputs | |
4116 | * (endpoint, asoc, chunk) | |
4117 | * | |
4118 | * Outputs | |
4119 | * (asoc, reply_msg, msg_up, timers, counters) | |
4120 | * | |
4121 | * The return value is the disposition of the chunk. | |
4122 | */ | |
4123 | sctp_disposition_t sctp_sf_discard_chunk(const struct sctp_endpoint *ep, | |
4124 | const struct sctp_association *asoc, | |
4125 | const sctp_subtype_t type, | |
4126 | void *arg, | |
4127 | sctp_cmd_seq_t *commands) | |
4128 | { | |
ece25dfa VY |
4129 | struct sctp_chunk *chunk = arg; |
4130 | ||
4131 | /* Make sure that the chunk has a valid length. | |
4132 | * Since we don't know the chunk type, we use a general | |
4133 | * chunkhdr structure to make a comparison. | |
4134 | */ | |
4135 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
4136 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4137 | commands); | |
4138 | ||
1da177e4 LT |
4139 | SCTP_DEBUG_PRINTK("Chunk %d is discarded\n", type.chunk); |
4140 | return SCTP_DISPOSITION_DISCARD; | |
4141 | } | |
4142 | ||
4143 | /* | |
4144 | * Discard the whole packet. | |
4145 | * | |
4146 | * Section: 8.4 2) | |
4147 | * | |
4148 | * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST | |
4149 | * silently discard the OOTB packet and take no further action. | |
1da177e4 LT |
4150 | * |
4151 | * Verification Tag: No verification necessary | |
4152 | * | |
4153 | * Inputs | |
4154 | * (endpoint, asoc, chunk) | |
4155 | * | |
4156 | * Outputs | |
4157 | * (asoc, reply_msg, msg_up, timers, counters) | |
4158 | * | |
4159 | * The return value is the disposition of the chunk. | |
4160 | */ | |
4161 | sctp_disposition_t sctp_sf_pdiscard(const struct sctp_endpoint *ep, | |
4162 | const struct sctp_association *asoc, | |
4163 | const sctp_subtype_t type, | |
4164 | void *arg, | |
4165 | sctp_cmd_seq_t *commands) | |
4166 | { | |
ac0b0462 | 4167 | SCTP_INC_STATS(SCTP_MIB_IN_PKT_DISCARDS); |
1da177e4 LT |
4168 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
4169 | ||
4170 | return SCTP_DISPOSITION_CONSUME; | |
4171 | } | |
4172 | ||
4173 | ||
4174 | /* | |
4175 | * The other end is violating protocol. | |
4176 | * | |
4177 | * Section: Not specified | |
4178 | * Verification Tag: Not specified | |
4179 | * Inputs | |
4180 | * (endpoint, asoc, chunk) | |
4181 | * | |
4182 | * Outputs | |
4183 | * (asoc, reply_msg, msg_up, timers, counters) | |
4184 | * | |
4185 | * We simply tag the chunk as a violation. The state machine will log | |
4186 | * the violation and continue. | |
4187 | */ | |
4188 | sctp_disposition_t sctp_sf_violation(const struct sctp_endpoint *ep, | |
4189 | const struct sctp_association *asoc, | |
4190 | const sctp_subtype_t type, | |
4191 | void *arg, | |
4192 | sctp_cmd_seq_t *commands) | |
4193 | { | |
ece25dfa VY |
4194 | struct sctp_chunk *chunk = arg; |
4195 | ||
4196 | /* Make sure that the chunk has a valid length. */ | |
4197 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
4198 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4199 | commands); | |
4200 | ||
1da177e4 LT |
4201 | return SCTP_DISPOSITION_VIOLATION; |
4202 | } | |
4203 | ||
1da177e4 | 4204 | /* |
aecedeab | 4205 | * Common function to handle a protocol violation. |
1da177e4 | 4206 | */ |
aecedeab | 4207 | static sctp_disposition_t sctp_sf_abort_violation( |
ece25dfa | 4208 | const struct sctp_endpoint *ep, |
1da177e4 | 4209 | const struct sctp_association *asoc, |
1da177e4 | 4210 | void *arg, |
aecedeab WY |
4211 | sctp_cmd_seq_t *commands, |
4212 | const __u8 *payload, | |
4213 | const size_t paylen) | |
1da177e4 | 4214 | { |
ece25dfa | 4215 | struct sctp_packet *packet = NULL; |
1da177e4 LT |
4216 | struct sctp_chunk *chunk = arg; |
4217 | struct sctp_chunk *abort = NULL; | |
1da177e4 | 4218 | |
bbd0d598 VY |
4219 | /* SCTP-AUTH, Section 6.3: |
4220 | * It should be noted that if the receiver wants to tear | |
4221 | * down an association in an authenticated way only, the | |
4222 | * handling of malformed packets should not result in | |
4223 | * tearing down the association. | |
4224 | * | |
4225 | * This means that if we only want to abort associations | |
4226 | * in an authenticated way (i.e AUTH+ABORT), then we | |
ac461a03 | 4227 | * can't destroy this association just becuase the packet |
bbd0d598 VY |
4228 | * was malformed. |
4229 | */ | |
4230 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
4231 | goto discard; | |
4232 | ||
9abed245 JJ |
4233 | /* Make the abort chunk. */ |
4234 | abort = sctp_make_abort_violation(asoc, chunk, payload, paylen); | |
4235 | if (!abort) | |
4236 | goto nomem; | |
4237 | ||
ece25dfa | 4238 | if (asoc) { |
f4ad85ca GJ |
4239 | /* Treat INIT-ACK as a special case during COOKIE-WAIT. */ |
4240 | if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK && | |
4241 | !asoc->peer.i.init_tag) { | |
4242 | sctp_initack_chunk_t *initack; | |
4243 | ||
4244 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
4245 | if (!sctp_chunk_length_valid(chunk, | |
4246 | sizeof(sctp_initack_chunk_t))) | |
4247 | abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T; | |
4248 | else { | |
4249 | unsigned int inittag; | |
4250 | ||
4251 | inittag = ntohl(initack->init_hdr.init_tag); | |
4252 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG, | |
4253 | SCTP_U32(inittag)); | |
4254 | } | |
4255 | } | |
4256 | ||
ece25dfa VY |
4257 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
4258 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 | 4259 | |
ece25dfa VY |
4260 | if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { |
4261 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4262 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4263 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4264 | SCTP_ERROR(ECONNREFUSED)); | |
4265 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
4266 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4267 | } else { | |
4268 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4269 | SCTP_ERROR(ECONNABORTED)); | |
4270 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4271 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4272 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4273 | } | |
1da177e4 | 4274 | } else { |
ece25dfa VY |
4275 | packet = sctp_ootb_pkt_new(asoc, chunk); |
4276 | ||
4277 | if (!packet) | |
4278 | goto nomem_pkt; | |
4279 | ||
4280 | if (sctp_test_T_bit(abort)) | |
4281 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
4282 | ||
4283 | abort->skb->sk = ep->base.sk; | |
4284 | ||
4285 | sctp_packet_append_chunk(packet, abort); | |
4286 | ||
4287 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
4288 | SCTP_PACKET(packet)); | |
4289 | ||
4290 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 LT |
4291 | } |
4292 | ||
1da177e4 | 4293 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
d808ad9a | 4294 | |
56eb82bb VY |
4295 | discard: |
4296 | sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); | |
1da177e4 LT |
4297 | return SCTP_DISPOSITION_ABORT; |
4298 | ||
ece25dfa VY |
4299 | nomem_pkt: |
4300 | sctp_chunk_free(abort); | |
1da177e4 LT |
4301 | nomem: |
4302 | return SCTP_DISPOSITION_NOMEM; | |
4303 | } | |
4304 | ||
aecedeab WY |
4305 | /* |
4306 | * Handle a protocol violation when the chunk length is invalid. | |
025dfdaf | 4307 | * "Invalid" length is identified as smaller than the minimal length a |
aecedeab | 4308 | * given chunk can be. For example, a SACK chunk has invalid length |
025dfdaf | 4309 | * if its length is set to be smaller than the size of sctp_sack_chunk_t. |
aecedeab WY |
4310 | * |
4311 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4312 | * error code. | |
4313 | * | |
4314 | * Section: Not specified | |
4315 | * Verification Tag: Nothing to do | |
4316 | * Inputs | |
4317 | * (endpoint, asoc, chunk) | |
4318 | * | |
4319 | * Outputs | |
4320 | * (reply_msg, msg_up, counters) | |
4321 | * | |
4322 | * Generate an ABORT chunk and terminate the association. | |
4323 | */ | |
4324 | static sctp_disposition_t sctp_sf_violation_chunklen( | |
4325 | const struct sctp_endpoint *ep, | |
4326 | const struct sctp_association *asoc, | |
4327 | const sctp_subtype_t type, | |
4328 | void *arg, | |
4329 | sctp_cmd_seq_t *commands) | |
4330 | { | |
2444844c | 4331 | static const char err_str[]="The following chunk had invalid length:"; |
aecedeab | 4332 | |
ece25dfa | 4333 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
4334 | sizeof(err_str)); |
4335 | } | |
4336 | ||
6f4c618d WY |
4337 | /* |
4338 | * Handle a protocol violation when the parameter length is invalid. | |
025dfdaf | 4339 | * "Invalid" length is identified as smaller than the minimal length a |
6f4c618d WY |
4340 | * given parameter can be. |
4341 | */ | |
4342 | static sctp_disposition_t sctp_sf_violation_paramlen( | |
4343 | const struct sctp_endpoint *ep, | |
4344 | const struct sctp_association *asoc, | |
4345 | const sctp_subtype_t type, | |
ba016670 WY |
4346 | void *arg, void *ext, |
4347 | sctp_cmd_seq_t *commands) | |
4348 | { | |
4349 | struct sctp_chunk *chunk = arg; | |
4350 | struct sctp_paramhdr *param = ext; | |
4351 | struct sctp_chunk *abort = NULL; | |
6f4c618d | 4352 | |
ba016670 WY |
4353 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) |
4354 | goto discard; | |
4355 | ||
4356 | /* Make the abort chunk. */ | |
4357 | abort = sctp_make_violation_paramlen(asoc, chunk, param); | |
4358 | if (!abort) | |
4359 | goto nomem; | |
4360 | ||
4361 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
4362 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
4363 | ||
4364 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4365 | SCTP_ERROR(ECONNABORTED)); | |
4366 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4367 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4368 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
56eb82bb | 4369 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
ba016670 WY |
4370 | |
4371 | discard: | |
4372 | sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); | |
ba016670 WY |
4373 | return SCTP_DISPOSITION_ABORT; |
4374 | nomem: | |
4375 | return SCTP_DISPOSITION_NOMEM; | |
6f4c618d WY |
4376 | } |
4377 | ||
aecedeab WY |
4378 | /* Handle a protocol violation when the peer trying to advance the |
4379 | * cumulative tsn ack to a point beyond the max tsn currently sent. | |
4380 | * | |
4381 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4382 | * error code. | |
4383 | */ | |
4384 | static sctp_disposition_t sctp_sf_violation_ctsn( | |
4385 | const struct sctp_endpoint *ep, | |
4386 | const struct sctp_association *asoc, | |
4387 | const sctp_subtype_t type, | |
4388 | void *arg, | |
4389 | sctp_cmd_seq_t *commands) | |
4390 | { | |
2444844c | 4391 | static const char err_str[]="The cumulative tsn ack beyond the max tsn currently sent:"; |
aecedeab | 4392 | |
ece25dfa | 4393 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
4394 | sizeof(err_str)); |
4395 | } | |
4396 | ||
ece25dfa VY |
4397 | /* Handle protocol violation of an invalid chunk bundling. For example, |
4398 | * when we have an association and we recieve bundled INIT-ACK, or | |
4399 | * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle" | |
4400 | * statement from the specs. Additinally, there might be an attacker | |
4401 | * on the path and we may not want to continue this communication. | |
4402 | */ | |
4403 | static sctp_disposition_t sctp_sf_violation_chunk( | |
4404 | const struct sctp_endpoint *ep, | |
4405 | const struct sctp_association *asoc, | |
4406 | const sctp_subtype_t type, | |
4407 | void *arg, | |
4408 | sctp_cmd_seq_t *commands) | |
4409 | { | |
2444844c | 4410 | static const char err_str[]="The following chunk violates protocol:"; |
ece25dfa VY |
4411 | |
4412 | if (!asoc) | |
4413 | return sctp_sf_violation(ep, asoc, type, arg, commands); | |
4414 | ||
4415 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, | |
4416 | sizeof(err_str)); | |
4417 | } | |
1da177e4 LT |
4418 | /*************************************************************************** |
4419 | * These are the state functions for handling primitive (Section 10) events. | |
4420 | ***************************************************************************/ | |
4421 | /* | |
4422 | * sctp_sf_do_prm_asoc | |
4423 | * | |
4424 | * Section: 10.1 ULP-to-SCTP | |
4425 | * B) Associate | |
4426 | * | |
4427 | * Format: ASSOCIATE(local SCTP instance name, destination transport addr, | |
4428 | * outbound stream count) | |
4429 | * -> association id [,destination transport addr list] [,outbound stream | |
4430 | * count] | |
4431 | * | |
4432 | * This primitive allows the upper layer to initiate an association to a | |
4433 | * specific peer endpoint. | |
4434 | * | |
4435 | * The peer endpoint shall be specified by one of the transport addresses | |
4436 | * which defines the endpoint (see Section 1.4). If the local SCTP | |
4437 | * instance has not been initialized, the ASSOCIATE is considered an | |
4438 | * error. | |
4439 | * [This is not relevant for the kernel implementation since we do all | |
4440 | * initialization at boot time. It we hadn't initialized we wouldn't | |
4441 | * get anywhere near this code.] | |
4442 | * | |
4443 | * An association id, which is a local handle to the SCTP association, | |
4444 | * will be returned on successful establishment of the association. If | |
4445 | * SCTP is not able to open an SCTP association with the peer endpoint, | |
4446 | * an error is returned. | |
4447 | * [In the kernel implementation, the struct sctp_association needs to | |
4448 | * be created BEFORE causing this primitive to run.] | |
4449 | * | |
4450 | * Other association parameters may be returned, including the | |
4451 | * complete destination transport addresses of the peer as well as the | |
4452 | * outbound stream count of the local endpoint. One of the transport | |
4453 | * address from the returned destination addresses will be selected by | |
4454 | * the local endpoint as default primary path for sending SCTP packets | |
4455 | * to this peer. The returned "destination transport addr list" can | |
4456 | * be used by the ULP to change the default primary path or to force | |
4457 | * sending a packet to a specific transport address. [All of this | |
4458 | * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING | |
4459 | * function.] | |
4460 | * | |
4461 | * Mandatory attributes: | |
4462 | * | |
4463 | * o local SCTP instance name - obtained from the INITIALIZE operation. | |
4464 | * [This is the argument asoc.] | |
4465 | * o destination transport addr - specified as one of the transport | |
4466 | * addresses of the peer endpoint with which the association is to be | |
4467 | * established. | |
4468 | * [This is asoc->peer.active_path.] | |
4469 | * o outbound stream count - the number of outbound streams the ULP | |
4470 | * would like to open towards this peer endpoint. | |
4471 | * [BUG: This is not currently implemented.] | |
4472 | * Optional attributes: | |
4473 | * | |
4474 | * None. | |
4475 | * | |
4476 | * The return value is a disposition. | |
4477 | */ | |
4478 | sctp_disposition_t sctp_sf_do_prm_asoc(const struct sctp_endpoint *ep, | |
4479 | const struct sctp_association *asoc, | |
4480 | const sctp_subtype_t type, | |
4481 | void *arg, | |
4482 | sctp_cmd_seq_t *commands) | |
4483 | { | |
4484 | struct sctp_chunk *repl; | |
ab38fb04 | 4485 | struct sctp_association* my_asoc; |
1da177e4 LT |
4486 | |
4487 | /* The comment below says that we enter COOKIE-WAIT AFTER | |
4488 | * sending the INIT, but that doesn't actually work in our | |
4489 | * implementation... | |
4490 | */ | |
4491 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4492 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
4493 | ||
4494 | /* RFC 2960 5.1 Normal Establishment of an Association | |
4495 | * | |
4496 | * A) "A" first sends an INIT chunk to "Z". In the INIT, "A" | |
4497 | * must provide its Verification Tag (Tag_A) in the Initiate | |
4498 | * Tag field. Tag_A SHOULD be a random number in the range of | |
4499 | * 1 to 4294967295 (see 5.3.1 for Tag value selection). ... | |
4500 | */ | |
4501 | ||
4502 | repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0); | |
4503 | if (!repl) | |
4504 | goto nomem; | |
4505 | ||
4506 | /* Cast away the const modifier, as we want to just | |
4507 | * rerun it through as a sideffect. | |
4508 | */ | |
ab38fb04 VY |
4509 | my_asoc = (struct sctp_association *)asoc; |
4510 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc)); | |
1da177e4 | 4511 | |
3f7a87d2 FF |
4512 | /* Choose transport for INIT. */ |
4513 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4514 | SCTP_CHUNK(repl)); | |
4515 | ||
1da177e4 LT |
4516 | /* After sending the INIT, "A" starts the T1-init timer and |
4517 | * enters the COOKIE-WAIT state. | |
4518 | */ | |
4519 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4520 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4521 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4522 | return SCTP_DISPOSITION_CONSUME; | |
4523 | ||
4524 | nomem: | |
4525 | return SCTP_DISPOSITION_NOMEM; | |
4526 | } | |
4527 | ||
4528 | /* | |
4529 | * Process the SEND primitive. | |
4530 | * | |
4531 | * Section: 10.1 ULP-to-SCTP | |
4532 | * E) Send | |
4533 | * | |
4534 | * Format: SEND(association id, buffer address, byte count [,context] | |
4535 | * [,stream id] [,life time] [,destination transport address] | |
4536 | * [,unorder flag] [,no-bundle flag] [,payload protocol-id] ) | |
4537 | * -> result | |
4538 | * | |
4539 | * This is the main method to send user data via SCTP. | |
4540 | * | |
4541 | * Mandatory attributes: | |
4542 | * | |
4543 | * o association id - local handle to the SCTP association | |
4544 | * | |
4545 | * o buffer address - the location where the user message to be | |
4546 | * transmitted is stored; | |
4547 | * | |
4548 | * o byte count - The size of the user data in number of bytes; | |
4549 | * | |
4550 | * Optional attributes: | |
4551 | * | |
4552 | * o context - an optional 32 bit integer that will be carried in the | |
4553 | * sending failure notification to the ULP if the transportation of | |
4554 | * this User Message fails. | |
4555 | * | |
4556 | * o stream id - to indicate which stream to send the data on. If not | |
4557 | * specified, stream 0 will be used. | |
4558 | * | |
4559 | * o life time - specifies the life time of the user data. The user data | |
4560 | * will not be sent by SCTP after the life time expires. This | |
4561 | * parameter can be used to avoid efforts to transmit stale | |
4562 | * user messages. SCTP notifies the ULP if the data cannot be | |
4563 | * initiated to transport (i.e. sent to the destination via SCTP's | |
4564 | * send primitive) within the life time variable. However, the | |
4565 | * user data will be transmitted if SCTP has attempted to transmit a | |
4566 | * chunk before the life time expired. | |
4567 | * | |
4568 | * o destination transport address - specified as one of the destination | |
4569 | * transport addresses of the peer endpoint to which this packet | |
4570 | * should be sent. Whenever possible, SCTP should use this destination | |
4571 | * transport address for sending the packets, instead of the current | |
4572 | * primary path. | |
4573 | * | |
4574 | * o unorder flag - this flag, if present, indicates that the user | |
4575 | * would like the data delivered in an unordered fashion to the peer | |
4576 | * (i.e., the U flag is set to 1 on all DATA chunks carrying this | |
4577 | * message). | |
4578 | * | |
4579 | * o no-bundle flag - instructs SCTP not to bundle this user data with | |
4580 | * other outbound DATA chunks. SCTP MAY still bundle even when | |
4581 | * this flag is present, when faced with network congestion. | |
4582 | * | |
4583 | * o payload protocol-id - A 32 bit unsigned integer that is to be | |
4584 | * passed to the peer indicating the type of payload protocol data | |
4585 | * being transmitted. This value is passed as opaque data by SCTP. | |
4586 | * | |
4587 | * The return value is the disposition. | |
4588 | */ | |
4589 | sctp_disposition_t sctp_sf_do_prm_send(const struct sctp_endpoint *ep, | |
4590 | const struct sctp_association *asoc, | |
4591 | const sctp_subtype_t type, | |
4592 | void *arg, | |
4593 | sctp_cmd_seq_t *commands) | |
4594 | { | |
9c5c62be | 4595 | struct sctp_datamsg *msg = arg; |
1da177e4 | 4596 | |
9c5c62be | 4597 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_MSG, SCTP_DATAMSG(msg)); |
1da177e4 LT |
4598 | return SCTP_DISPOSITION_CONSUME; |
4599 | } | |
4600 | ||
4601 | /* | |
4602 | * Process the SHUTDOWN primitive. | |
4603 | * | |
4604 | * Section: 10.1: | |
4605 | * C) Shutdown | |
4606 | * | |
4607 | * Format: SHUTDOWN(association id) | |
4608 | * -> result | |
4609 | * | |
4610 | * Gracefully closes an association. Any locally queued user data | |
4611 | * will be delivered to the peer. The association will be terminated only | |
4612 | * after the peer acknowledges all the SCTP packets sent. A success code | |
4613 | * will be returned on successful termination of the association. If | |
4614 | * attempting to terminate the association results in a failure, an error | |
4615 | * code shall be returned. | |
4616 | * | |
4617 | * Mandatory attributes: | |
4618 | * | |
4619 | * o association id - local handle to the SCTP association | |
4620 | * | |
4621 | * Optional attributes: | |
4622 | * | |
4623 | * None. | |
4624 | * | |
4625 | * The return value is the disposition. | |
4626 | */ | |
4627 | sctp_disposition_t sctp_sf_do_9_2_prm_shutdown( | |
4628 | const struct sctp_endpoint *ep, | |
4629 | const struct sctp_association *asoc, | |
4630 | const sctp_subtype_t type, | |
4631 | void *arg, | |
4632 | sctp_cmd_seq_t *commands) | |
4633 | { | |
4634 | int disposition; | |
4635 | ||
4636 | /* From 9.2 Shutdown of an Association | |
4637 | * Upon receipt of the SHUTDOWN primitive from its upper | |
4638 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
4639 | * remains there until all outstanding data has been | |
4640 | * acknowledged by its peer. The endpoint accepts no new data | |
4641 | * from its upper layer, but retransmits data to the far end | |
4642 | * if necessary to fill gaps. | |
4643 | */ | |
4644 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4645 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
4646 | ||
1da177e4 LT |
4647 | disposition = SCTP_DISPOSITION_CONSUME; |
4648 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
4649 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
4650 | arg, commands); | |
4651 | } | |
4652 | return disposition; | |
4653 | } | |
4654 | ||
4655 | /* | |
4656 | * Process the ABORT primitive. | |
4657 | * | |
4658 | * Section: 10.1: | |
4659 | * C) Abort | |
4660 | * | |
4661 | * Format: Abort(association id [, cause code]) | |
4662 | * -> result | |
4663 | * | |
4664 | * Ungracefully closes an association. Any locally queued user data | |
4665 | * will be discarded and an ABORT chunk is sent to the peer. A success code | |
4666 | * will be returned on successful abortion of the association. If | |
4667 | * attempting to abort the association results in a failure, an error | |
4668 | * code shall be returned. | |
4669 | * | |
4670 | * Mandatory attributes: | |
4671 | * | |
4672 | * o association id - local handle to the SCTP association | |
4673 | * | |
4674 | * Optional attributes: | |
4675 | * | |
4676 | * o cause code - reason of the abort to be passed to the peer | |
4677 | * | |
4678 | * None. | |
4679 | * | |
4680 | * The return value is the disposition. | |
4681 | */ | |
4682 | sctp_disposition_t sctp_sf_do_9_1_prm_abort( | |
4683 | const struct sctp_endpoint *ep, | |
4684 | const struct sctp_association *asoc, | |
4685 | const sctp_subtype_t type, | |
4686 | void *arg, | |
4687 | sctp_cmd_seq_t *commands) | |
4688 | { | |
4689 | /* From 9.1 Abort of an Association | |
4690 | * Upon receipt of the ABORT primitive from its upper | |
4691 | * layer, the endpoint enters CLOSED state and | |
4692 | * discard all outstanding data has been | |
4693 | * acknowledged by its peer. The endpoint accepts no new data | |
4694 | * from its upper layer, but retransmits data to the far end | |
4695 | * if necessary to fill gaps. | |
4696 | */ | |
c164a9ba | 4697 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4698 | sctp_disposition_t retval; |
4699 | ||
4700 | retval = SCTP_DISPOSITION_CONSUME; | |
4701 | ||
c164a9ba | 4702 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4703 | |
4704 | /* Even if we can't send the ABORT due to low memory delete the | |
4705 | * TCB. This is a departure from our typical NOMEM handling. | |
4706 | */ | |
4707 | ||
8de8c873 SS |
4708 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4709 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 LT |
4710 | /* Delete the established association. */ |
4711 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4712 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4713 | |
4714 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4715 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4716 | ||
4717 | return retval; | |
4718 | } | |
4719 | ||
4720 | /* We tried an illegal operation on an association which is closed. */ | |
4721 | sctp_disposition_t sctp_sf_error_closed(const struct sctp_endpoint *ep, | |
4722 | const struct sctp_association *asoc, | |
4723 | const sctp_subtype_t type, | |
4724 | void *arg, | |
4725 | sctp_cmd_seq_t *commands) | |
4726 | { | |
4727 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL)); | |
4728 | return SCTP_DISPOSITION_CONSUME; | |
4729 | } | |
4730 | ||
4731 | /* We tried an illegal operation on an association which is shutting | |
4732 | * down. | |
4733 | */ | |
4734 | sctp_disposition_t sctp_sf_error_shutdown(const struct sctp_endpoint *ep, | |
4735 | const struct sctp_association *asoc, | |
4736 | const sctp_subtype_t type, | |
4737 | void *arg, | |
4738 | sctp_cmd_seq_t *commands) | |
4739 | { | |
4740 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, | |
4741 | SCTP_ERROR(-ESHUTDOWN)); | |
4742 | return SCTP_DISPOSITION_CONSUME; | |
4743 | } | |
4744 | ||
4745 | /* | |
4746 | * sctp_cookie_wait_prm_shutdown | |
4747 | * | |
4748 | * Section: 4 Note: 2 | |
4749 | * Verification Tag: | |
4750 | * Inputs | |
4751 | * (endpoint, asoc) | |
4752 | * | |
4753 | * The RFC does not explicitly address this issue, but is the route through the | |
4754 | * state table when someone issues a shutdown while in COOKIE_WAIT state. | |
4755 | * | |
4756 | * Outputs | |
4757 | * (timers) | |
4758 | */ | |
4759 | sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown( | |
4760 | const struct sctp_endpoint *ep, | |
4761 | const struct sctp_association *asoc, | |
4762 | const sctp_subtype_t type, | |
4763 | void *arg, | |
4764 | sctp_cmd_seq_t *commands) | |
4765 | { | |
4766 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4767 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4768 | ||
4769 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4770 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4771 | ||
4772 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
4773 | ||
4774 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
4775 | ||
4776 | return SCTP_DISPOSITION_DELETE_TCB; | |
4777 | } | |
4778 | ||
4779 | /* | |
4780 | * sctp_cookie_echoed_prm_shutdown | |
4781 | * | |
4782 | * Section: 4 Note: 2 | |
4783 | * Verification Tag: | |
4784 | * Inputs | |
4785 | * (endpoint, asoc) | |
4786 | * | |
4787 | * The RFC does not explcitly address this issue, but is the route through the | |
4788 | * state table when someone issues a shutdown while in COOKIE_ECHOED state. | |
4789 | * | |
4790 | * Outputs | |
4791 | * (timers) | |
4792 | */ | |
4793 | sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown( | |
4794 | const struct sctp_endpoint *ep, | |
4795 | const struct sctp_association *asoc, | |
4796 | const sctp_subtype_t type, | |
4797 | void *arg, sctp_cmd_seq_t *commands) | |
4798 | { | |
4799 | /* There is a single T1 timer, so we should be able to use | |
4800 | * common function with the COOKIE-WAIT state. | |
4801 | */ | |
4802 | return sctp_sf_cookie_wait_prm_shutdown(ep, asoc, type, arg, commands); | |
4803 | } | |
4804 | ||
4805 | /* | |
4806 | * sctp_sf_cookie_wait_prm_abort | |
4807 | * | |
4808 | * Section: 4 Note: 2 | |
4809 | * Verification Tag: | |
4810 | * Inputs | |
4811 | * (endpoint, asoc) | |
4812 | * | |
4813 | * The RFC does not explicitly address this issue, but is the route through the | |
4814 | * state table when someone issues an abort while in COOKIE_WAIT state. | |
4815 | * | |
4816 | * Outputs | |
4817 | * (timers) | |
4818 | */ | |
4819 | sctp_disposition_t sctp_sf_cookie_wait_prm_abort( | |
4820 | const struct sctp_endpoint *ep, | |
4821 | const struct sctp_association *asoc, | |
4822 | const sctp_subtype_t type, | |
4823 | void *arg, | |
4824 | sctp_cmd_seq_t *commands) | |
4825 | { | |
c164a9ba | 4826 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4827 | sctp_disposition_t retval; |
4828 | ||
4829 | /* Stop T1-init timer */ | |
4830 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4831 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4832 | retval = SCTP_DISPOSITION_CONSUME; | |
4833 | ||
c164a9ba | 4834 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4835 | |
4836 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4837 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4838 | ||
4839 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4840 | ||
4841 | /* Even if we can't send the ABORT due to low memory delete the | |
4842 | * TCB. This is a departure from our typical NOMEM handling. | |
4843 | */ | |
4844 | ||
8de8c873 SS |
4845 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4846 | SCTP_ERROR(ECONNREFUSED)); | |
1da177e4 LT |
4847 | /* Delete the established association. */ |
4848 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 4849 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4850 | |
4851 | return retval; | |
4852 | } | |
4853 | ||
4854 | /* | |
4855 | * sctp_sf_cookie_echoed_prm_abort | |
4856 | * | |
4857 | * Section: 4 Note: 3 | |
4858 | * Verification Tag: | |
4859 | * Inputs | |
4860 | * (endpoint, asoc) | |
4861 | * | |
4862 | * The RFC does not explcitly address this issue, but is the route through the | |
4863 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4864 | * | |
4865 | * Outputs | |
4866 | * (timers) | |
4867 | */ | |
4868 | sctp_disposition_t sctp_sf_cookie_echoed_prm_abort( | |
4869 | const struct sctp_endpoint *ep, | |
4870 | const struct sctp_association *asoc, | |
4871 | const sctp_subtype_t type, | |
4872 | void *arg, | |
4873 | sctp_cmd_seq_t *commands) | |
4874 | { | |
4875 | /* There is a single T1 timer, so we should be able to use | |
4876 | * common function with the COOKIE-WAIT state. | |
4877 | */ | |
4878 | return sctp_sf_cookie_wait_prm_abort(ep, asoc, type, arg, commands); | |
4879 | } | |
4880 | ||
4881 | /* | |
4882 | * sctp_sf_shutdown_pending_prm_abort | |
4883 | * | |
4884 | * Inputs | |
4885 | * (endpoint, asoc) | |
4886 | * | |
4887 | * The RFC does not explicitly address this issue, but is the route through the | |
4888 | * state table when someone issues an abort while in SHUTDOWN-PENDING state. | |
4889 | * | |
4890 | * Outputs | |
4891 | * (timers) | |
4892 | */ | |
4893 | sctp_disposition_t sctp_sf_shutdown_pending_prm_abort( | |
4894 | const struct sctp_endpoint *ep, | |
4895 | const struct sctp_association *asoc, | |
4896 | const sctp_subtype_t type, | |
4897 | void *arg, | |
4898 | sctp_cmd_seq_t *commands) | |
4899 | { | |
4900 | /* Stop the T5-shutdown guard timer. */ | |
4901 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4902 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4903 | ||
4904 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4905 | } | |
4906 | ||
4907 | /* | |
4908 | * sctp_sf_shutdown_sent_prm_abort | |
4909 | * | |
4910 | * Inputs | |
4911 | * (endpoint, asoc) | |
4912 | * | |
4913 | * The RFC does not explicitly address this issue, but is the route through the | |
4914 | * state table when someone issues an abort while in SHUTDOWN-SENT state. | |
4915 | * | |
4916 | * Outputs | |
4917 | * (timers) | |
4918 | */ | |
4919 | sctp_disposition_t sctp_sf_shutdown_sent_prm_abort( | |
4920 | const struct sctp_endpoint *ep, | |
4921 | const struct sctp_association *asoc, | |
4922 | const sctp_subtype_t type, | |
4923 | void *arg, | |
4924 | sctp_cmd_seq_t *commands) | |
4925 | { | |
4926 | /* Stop the T2-shutdown timer. */ | |
4927 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4928 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4929 | ||
4930 | /* Stop the T5-shutdown guard timer. */ | |
4931 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4932 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4933 | ||
4934 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4935 | } | |
4936 | ||
4937 | /* | |
4938 | * sctp_sf_cookie_echoed_prm_abort | |
4939 | * | |
4940 | * Inputs | |
4941 | * (endpoint, asoc) | |
4942 | * | |
4943 | * The RFC does not explcitly address this issue, but is the route through the | |
4944 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4945 | * | |
4946 | * Outputs | |
4947 | * (timers) | |
4948 | */ | |
4949 | sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort( | |
4950 | const struct sctp_endpoint *ep, | |
4951 | const struct sctp_association *asoc, | |
4952 | const sctp_subtype_t type, | |
4953 | void *arg, | |
4954 | sctp_cmd_seq_t *commands) | |
4955 | { | |
4956 | /* The same T2 timer, so we should be able to use | |
4957 | * common function with the SHUTDOWN-SENT state. | |
4958 | */ | |
4959 | return sctp_sf_shutdown_sent_prm_abort(ep, asoc, type, arg, commands); | |
4960 | } | |
4961 | ||
4962 | /* | |
4963 | * Process the REQUESTHEARTBEAT primitive | |
4964 | * | |
4965 | * 10.1 ULP-to-SCTP | |
4966 | * J) Request Heartbeat | |
4967 | * | |
4968 | * Format: REQUESTHEARTBEAT(association id, destination transport address) | |
4969 | * | |
4970 | * -> result | |
4971 | * | |
4972 | * Instructs the local endpoint to perform a HeartBeat on the specified | |
4973 | * destination transport address of the given association. The returned | |
4974 | * result should indicate whether the transmission of the HEARTBEAT | |
4975 | * chunk to the destination address is successful. | |
4976 | * | |
4977 | * Mandatory attributes: | |
4978 | * | |
4979 | * o association id - local handle to the SCTP association | |
4980 | * | |
4981 | * o destination transport address - the transport address of the | |
4982 | * association on which a heartbeat should be issued. | |
4983 | */ | |
4984 | sctp_disposition_t sctp_sf_do_prm_requestheartbeat( | |
4985 | const struct sctp_endpoint *ep, | |
4986 | const struct sctp_association *asoc, | |
4987 | const sctp_subtype_t type, | |
4988 | void *arg, | |
4989 | sctp_cmd_seq_t *commands) | |
4990 | { | |
fb78525a VY |
4991 | if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type, |
4992 | (struct sctp_transport *)arg, commands)) | |
4993 | return SCTP_DISPOSITION_NOMEM; | |
4994 | ||
4995 | /* | |
4996 | * RFC 2960 (bis), section 8.3 | |
4997 | * | |
4998 | * D) Request an on-demand HEARTBEAT on a specific destination | |
4999 | * transport address of a given association. | |
5000 | * | |
5001 | * The endpoint should increment the respective error counter of | |
5002 | * the destination transport address each time a HEARTBEAT is sent | |
5003 | * to that address and not acknowledged within one RTO. | |
5004 | * | |
5005 | */ | |
7e99013a | 5006 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_HB_SENT, |
fb78525a VY |
5007 | SCTP_TRANSPORT(arg)); |
5008 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5009 | } |
5010 | ||
5011 | /* | |
5012 | * ADDIP Section 4.1 ASCONF Chunk Procedures | |
5013 | * When an endpoint has an ASCONF signaled change to be sent to the | |
5014 | * remote endpoint it should do A1 to A9 | |
5015 | */ | |
5016 | sctp_disposition_t sctp_sf_do_prm_asconf(const struct sctp_endpoint *ep, | |
5017 | const struct sctp_association *asoc, | |
5018 | const sctp_subtype_t type, | |
5019 | void *arg, | |
5020 | sctp_cmd_seq_t *commands) | |
5021 | { | |
5022 | struct sctp_chunk *chunk = arg; | |
5023 | ||
5024 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5025 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5026 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5027 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
5028 | return SCTP_DISPOSITION_CONSUME; | |
5029 | } | |
5030 | ||
5031 | /* | |
5032 | * Ignore the primitive event | |
5033 | * | |
5034 | * The return value is the disposition of the primitive. | |
5035 | */ | |
5036 | sctp_disposition_t sctp_sf_ignore_primitive( | |
5037 | const struct sctp_endpoint *ep, | |
5038 | const struct sctp_association *asoc, | |
5039 | const sctp_subtype_t type, | |
5040 | void *arg, | |
5041 | sctp_cmd_seq_t *commands) | |
5042 | { | |
5043 | SCTP_DEBUG_PRINTK("Primitive type %d is ignored.\n", type.primitive); | |
5044 | return SCTP_DISPOSITION_DISCARD; | |
5045 | } | |
5046 | ||
5047 | /*************************************************************************** | |
5048 | * These are the state functions for the OTHER events. | |
5049 | ***************************************************************************/ | |
5050 | ||
5051 | /* | |
5052 | * Start the shutdown negotiation. | |
5053 | * | |
5054 | * From Section 9.2: | |
5055 | * Once all its outstanding data has been acknowledged, the endpoint | |
5056 | * shall send a SHUTDOWN chunk to its peer including in the Cumulative | |
5057 | * TSN Ack field the last sequential TSN it has received from the peer. | |
5058 | * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT | |
5059 | * state. If the timer expires, the endpoint must re-send the SHUTDOWN | |
5060 | * with the updated last sequential TSN received from its peer. | |
5061 | * | |
5062 | * The return value is the disposition. | |
5063 | */ | |
5064 | sctp_disposition_t sctp_sf_do_9_2_start_shutdown( | |
5065 | const struct sctp_endpoint *ep, | |
5066 | const struct sctp_association *asoc, | |
5067 | const sctp_subtype_t type, | |
5068 | void *arg, | |
5069 | sctp_cmd_seq_t *commands) | |
5070 | { | |
5071 | struct sctp_chunk *reply; | |
5072 | ||
5073 | /* Once all its outstanding data has been acknowledged, the | |
5074 | * endpoint shall send a SHUTDOWN chunk to its peer including | |
5075 | * in the Cumulative TSN Ack field the last sequential TSN it | |
5076 | * has received from the peer. | |
5077 | */ | |
5078 | reply = sctp_make_shutdown(asoc, NULL); | |
5079 | if (!reply) | |
5080 | goto nomem; | |
5081 | ||
5082 | /* Set the transport for the SHUTDOWN chunk and the timeout for the | |
5083 | * T2-shutdown timer. | |
5084 | */ | |
5085 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5086 | ||
5087 | /* It shall then start the T2-shutdown timer */ | |
5088 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5089 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5090 | ||
536428a9 WY |
5091 | /* RFC 4960 Section 9.2 |
5092 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5093 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5094 | */ | |
5095 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
5096 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5097 | ||
1da177e4 LT |
5098 | if (asoc->autoclose) |
5099 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5100 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5101 | ||
5102 | /* and enter the SHUTDOWN-SENT state. */ | |
5103 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5104 | SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT)); | |
5105 | ||
5106 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5107 | * | |
5108 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5109 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5110 | */ |
5111 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5112 | ||
5113 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5114 | ||
5115 | return SCTP_DISPOSITION_CONSUME; | |
5116 | ||
5117 | nomem: | |
5118 | return SCTP_DISPOSITION_NOMEM; | |
5119 | } | |
5120 | ||
5121 | /* | |
5122 | * Generate a SHUTDOWN ACK now that everything is SACK'd. | |
5123 | * | |
5124 | * From Section 9.2: | |
5125 | * | |
5126 | * If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5127 | * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own, | |
5128 | * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the | |
5129 | * endpoint must re-send the SHUTDOWN ACK. | |
5130 | * | |
5131 | * The return value is the disposition. | |
5132 | */ | |
5133 | sctp_disposition_t sctp_sf_do_9_2_shutdown_ack( | |
5134 | const struct sctp_endpoint *ep, | |
5135 | const struct sctp_association *asoc, | |
5136 | const sctp_subtype_t type, | |
5137 | void *arg, | |
5138 | sctp_cmd_seq_t *commands) | |
5139 | { | |
5140 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
5141 | struct sctp_chunk *reply; | |
5142 | ||
5143 | /* There are 2 ways of getting here: | |
5144 | * 1) called in response to a SHUTDOWN chunk | |
5145 | * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued. | |
5146 | * | |
5147 | * For the case (2), the arg parameter is set to NULL. We need | |
5148 | * to check that we have a chunk before accessing it's fields. | |
5149 | */ | |
5150 | if (chunk) { | |
5151 | if (!sctp_vtag_verify(chunk, asoc)) | |
5152 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
5153 | ||
5154 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
5155 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t))) | |
5156 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
5157 | commands); | |
5158 | } | |
5159 | ||
5160 | /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5161 | * shall send a SHUTDOWN ACK ... | |
5162 | */ | |
5163 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
5164 | if (!reply) | |
5165 | goto nomem; | |
5166 | ||
5167 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
5168 | * the T2-shutdown timer. | |
5169 | */ | |
5170 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5171 | ||
5172 | /* and start/restart a T2-shutdown timer of its own, */ | |
5173 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5174 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5175 | ||
5176 | if (asoc->autoclose) | |
5177 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5178 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5179 | ||
5180 | /* Enter the SHUTDOWN-ACK-SENT state. */ | |
5181 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5182 | SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT)); | |
5183 | ||
5184 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5185 | * | |
5186 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5187 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5188 | */ |
5189 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5190 | ||
5191 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5192 | ||
5193 | return SCTP_DISPOSITION_CONSUME; | |
5194 | ||
5195 | nomem: | |
5196 | return SCTP_DISPOSITION_NOMEM; | |
5197 | } | |
5198 | ||
5199 | /* | |
5200 | * Ignore the event defined as other | |
5201 | * | |
5202 | * The return value is the disposition of the event. | |
5203 | */ | |
5204 | sctp_disposition_t sctp_sf_ignore_other(const struct sctp_endpoint *ep, | |
5205 | const struct sctp_association *asoc, | |
5206 | const sctp_subtype_t type, | |
5207 | void *arg, | |
5208 | sctp_cmd_seq_t *commands) | |
5209 | { | |
5210 | SCTP_DEBUG_PRINTK("The event other type %d is ignored\n", type.other); | |
5211 | return SCTP_DISPOSITION_DISCARD; | |
5212 | } | |
5213 | ||
5214 | /************************************************************ | |
5215 | * These are the state functions for handling timeout events. | |
5216 | ************************************************************/ | |
5217 | ||
5218 | /* | |
5219 | * RTX Timeout | |
5220 | * | |
5221 | * Section: 6.3.3 Handle T3-rtx Expiration | |
5222 | * | |
5223 | * Whenever the retransmission timer T3-rtx expires for a destination | |
5224 | * address, do the following: | |
5225 | * [See below] | |
5226 | * | |
5227 | * The return value is the disposition of the chunk. | |
5228 | */ | |
5229 | sctp_disposition_t sctp_sf_do_6_3_3_rtx(const struct sctp_endpoint *ep, | |
5230 | const struct sctp_association *asoc, | |
5231 | const sctp_subtype_t type, | |
5232 | void *arg, | |
5233 | sctp_cmd_seq_t *commands) | |
5234 | { | |
5235 | struct sctp_transport *transport = arg; | |
5236 | ||
ac0b0462 SS |
5237 | SCTP_INC_STATS(SCTP_MIB_T3_RTX_EXPIREDS); |
5238 | ||
1da177e4 | 5239 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5240 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5241 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5242 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5243 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5244 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5245 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5246 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5247 | return SCTP_DISPOSITION_DELETE_TCB; | |
5248 | } | |
5249 | ||
5250 | /* E1) For the destination address for which the timer | |
5251 | * expires, adjust its ssthresh with rules defined in Section | |
5252 | * 7.2.3 and set the cwnd <- MTU. | |
5253 | */ | |
5254 | ||
5255 | /* E2) For the destination address for which the timer | |
5256 | * expires, set RTO <- RTO * 2 ("back off the timer"). The | |
5257 | * maximum value discussed in rule C7 above (RTO.max) may be | |
5258 | * used to provide an upper bound to this doubling operation. | |
5259 | */ | |
5260 | ||
5261 | /* E3) Determine how many of the earliest (i.e., lowest TSN) | |
5262 | * outstanding DATA chunks for the address for which the | |
5263 | * T3-rtx has expired will fit into a single packet, subject | |
5264 | * to the MTU constraint for the path corresponding to the | |
5265 | * destination transport address to which the retransmission | |
5266 | * is being sent (this may be different from the address for | |
5267 | * which the timer expires [see Section 6.4]). Call this | |
5268 | * value K. Bundle and retransmit those K DATA chunks in a | |
5269 | * single packet to the destination endpoint. | |
5270 | * | |
5271 | * Note: Any DATA chunks that were sent to the address for | |
5272 | * which the T3-rtx timer expired but did not fit in one MTU | |
5273 | * (rule E3 above), should be marked for retransmission and | |
5274 | * sent as soon as cwnd allows (normally when a SACK arrives). | |
5275 | */ | |
5276 | ||
1da177e4 LT |
5277 | /* Do some failure management (Section 8.2). */ |
5278 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5279 | ||
1845a579 VY |
5280 | /* NB: Rules E4 and F1 are implicit in R1. */ |
5281 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport)); | |
5282 | ||
1da177e4 LT |
5283 | return SCTP_DISPOSITION_CONSUME; |
5284 | } | |
5285 | ||
5286 | /* | |
5287 | * Generate delayed SACK on timeout | |
5288 | * | |
5289 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
5290 | * | |
5291 | * The guidelines on delayed acknowledgement algorithm specified in | |
5292 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
5293 | * acknowledgement SHOULD be generated for at least every second packet | |
5294 | * (not every second DATA chunk) received, and SHOULD be generated | |
5295 | * within 200 ms of the arrival of any unacknowledged DATA chunk. In | |
5296 | * some situations it may be beneficial for an SCTP transmitter to be | |
5297 | * more conservative than the algorithms detailed in this document | |
5298 | * allow. However, an SCTP transmitter MUST NOT be more aggressive than | |
5299 | * the following algorithms allow. | |
5300 | */ | |
5301 | sctp_disposition_t sctp_sf_do_6_2_sack(const struct sctp_endpoint *ep, | |
5302 | const struct sctp_association *asoc, | |
5303 | const sctp_subtype_t type, | |
5304 | void *arg, | |
5305 | sctp_cmd_seq_t *commands) | |
5306 | { | |
ac0b0462 | 5307 | SCTP_INC_STATS(SCTP_MIB_DELAY_SACK_EXPIREDS); |
1da177e4 LT |
5308 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); |
5309 | return SCTP_DISPOSITION_CONSUME; | |
5310 | } | |
5311 | ||
5312 | /* | |
3f7a87d2 | 5313 | * sctp_sf_t1_init_timer_expire |
1da177e4 LT |
5314 | * |
5315 | * Section: 4 Note: 2 | |
5316 | * Verification Tag: | |
5317 | * Inputs | |
5318 | * (endpoint, asoc) | |
5319 | * | |
5320 | * RFC 2960 Section 4 Notes | |
5321 | * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT | |
5322 | * and re-start the T1-init timer without changing state. This MUST | |
5323 | * be repeated up to 'Max.Init.Retransmits' times. After that, the | |
5324 | * endpoint MUST abort the initialization process and report the | |
5325 | * error to SCTP user. | |
5326 | * | |
3f7a87d2 FF |
5327 | * Outputs |
5328 | * (timers, events) | |
5329 | * | |
5330 | */ | |
5331 | sctp_disposition_t sctp_sf_t1_init_timer_expire(const struct sctp_endpoint *ep, | |
5332 | const struct sctp_association *asoc, | |
5333 | const sctp_subtype_t type, | |
5334 | void *arg, | |
5335 | sctp_cmd_seq_t *commands) | |
5336 | { | |
5337 | struct sctp_chunk *repl = NULL; | |
5338 | struct sctp_bind_addr *bp; | |
5339 | int attempts = asoc->init_err_counter + 1; | |
5340 | ||
5341 | SCTP_DEBUG_PRINTK("Timer T1 expired (INIT).\n"); | |
ac0b0462 | 5342 | SCTP_INC_STATS(SCTP_MIB_T1_INIT_EXPIREDS); |
3f7a87d2 | 5343 | |
81845c21 | 5344 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 FF |
5345 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; |
5346 | repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0); | |
5347 | if (!repl) | |
5348 | return SCTP_DISPOSITION_NOMEM; | |
5349 | ||
5350 | /* Choose transport for INIT. */ | |
5351 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
5352 | SCTP_CHUNK(repl)); | |
5353 | ||
5354 | /* Issue a sideeffect to do the needed accounting. */ | |
5355 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART, | |
5356 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
5357 | ||
5358 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
5359 | } else { | |
5360 | SCTP_DEBUG_PRINTK("Giving up on INIT, attempts: %d" | |
5361 | " max_init_attempts: %d\n", | |
5362 | attempts, asoc->max_init_attempts); | |
8de8c873 SS |
5363 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5364 | SCTP_ERROR(ETIMEDOUT)); | |
3f7a87d2 | 5365 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5366 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
3f7a87d2 FF |
5367 | return SCTP_DISPOSITION_DELETE_TCB; |
5368 | } | |
5369 | ||
5370 | return SCTP_DISPOSITION_CONSUME; | |
5371 | } | |
5372 | ||
5373 | /* | |
5374 | * sctp_sf_t1_cookie_timer_expire | |
5375 | * | |
5376 | * Section: 4 Note: 2 | |
5377 | * Verification Tag: | |
5378 | * Inputs | |
5379 | * (endpoint, asoc) | |
5380 | * | |
5381 | * RFC 2960 Section 4 Notes | |
5382 | * 3) If the T1-cookie timer expires, the endpoint MUST retransmit | |
1da177e4 LT |
5383 | * COOKIE ECHO and re-start the T1-cookie timer without changing |
5384 | * state. This MUST be repeated up to 'Max.Init.Retransmits' times. | |
5385 | * After that, the endpoint MUST abort the initialization process and | |
5386 | * report the error to SCTP user. | |
5387 | * | |
5388 | * Outputs | |
5389 | * (timers, events) | |
5390 | * | |
5391 | */ | |
3f7a87d2 | 5392 | sctp_disposition_t sctp_sf_t1_cookie_timer_expire(const struct sctp_endpoint *ep, |
1da177e4 LT |
5393 | const struct sctp_association *asoc, |
5394 | const sctp_subtype_t type, | |
5395 | void *arg, | |
5396 | sctp_cmd_seq_t *commands) | |
5397 | { | |
3f7a87d2 FF |
5398 | struct sctp_chunk *repl = NULL; |
5399 | int attempts = asoc->init_err_counter + 1; | |
1da177e4 | 5400 | |
3f7a87d2 | 5401 | SCTP_DEBUG_PRINTK("Timer T1 expired (COOKIE-ECHO).\n"); |
ac0b0462 | 5402 | SCTP_INC_STATS(SCTP_MIB_T1_COOKIE_EXPIREDS); |
1da177e4 | 5403 | |
81845c21 | 5404 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 | 5405 | repl = sctp_make_cookie_echo(asoc, NULL); |
1da177e4 | 5406 | if (!repl) |
3f7a87d2 | 5407 | return SCTP_DISPOSITION_NOMEM; |
1da177e4 | 5408 | |
96cd0d3d VY |
5409 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, |
5410 | SCTP_CHUNK(repl)); | |
1da177e4 | 5411 | /* Issue a sideeffect to do the needed accounting. */ |
3f7a87d2 FF |
5412 | sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART, |
5413 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
5414 | ||
1da177e4 LT |
5415 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
5416 | } else { | |
8de8c873 SS |
5417 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5418 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5419 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5420 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5421 | return SCTP_DISPOSITION_DELETE_TCB; |
5422 | } | |
5423 | ||
5424 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5425 | } |
5426 | ||
5427 | /* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN | |
5428 | * with the updated last sequential TSN received from its peer. | |
5429 | * | |
5430 | * An endpoint should limit the number of retransmissions of the | |
5431 | * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'. | |
5432 | * If this threshold is exceeded the endpoint should destroy the TCB and | |
5433 | * MUST report the peer endpoint unreachable to the upper layer (and | |
5434 | * thus the association enters the CLOSED state). The reception of any | |
5435 | * packet from its peer (i.e. as the peer sends all of its queued DATA | |
5436 | * chunks) should clear the endpoint's retransmission count and restart | |
5437 | * the T2-Shutdown timer, giving its peer ample opportunity to transmit | |
5438 | * all of its queued DATA chunks that have not yet been sent. | |
5439 | */ | |
5440 | sctp_disposition_t sctp_sf_t2_timer_expire(const struct sctp_endpoint *ep, | |
5441 | const struct sctp_association *asoc, | |
5442 | const sctp_subtype_t type, | |
5443 | void *arg, | |
5444 | sctp_cmd_seq_t *commands) | |
5445 | { | |
5446 | struct sctp_chunk *reply = NULL; | |
5447 | ||
5448 | SCTP_DEBUG_PRINTK("Timer T2 expired.\n"); | |
ac0b0462 SS |
5449 | SCTP_INC_STATS(SCTP_MIB_T2_SHUTDOWN_EXPIREDS); |
5450 | ||
58fbbed4 NH |
5451 | ((struct sctp_association *)asoc)->shutdown_retries++; |
5452 | ||
1da177e4 | 5453 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5454 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5455 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5456 | /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5457 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5458 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5459 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5460 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5461 | return SCTP_DISPOSITION_DELETE_TCB; | |
5462 | } | |
5463 | ||
5464 | switch (asoc->state) { | |
5465 | case SCTP_STATE_SHUTDOWN_SENT: | |
5466 | reply = sctp_make_shutdown(asoc, NULL); | |
5467 | break; | |
5468 | ||
5469 | case SCTP_STATE_SHUTDOWN_ACK_SENT: | |
5470 | reply = sctp_make_shutdown_ack(asoc, NULL); | |
5471 | break; | |
5472 | ||
5473 | default: | |
5474 | BUG(); | |
5475 | break; | |
3ff50b79 | 5476 | } |
1da177e4 LT |
5477 | |
5478 | if (!reply) | |
5479 | goto nomem; | |
5480 | ||
6345b199 WY |
5481 | /* Do some failure management (Section 8.2). |
5482 | * If we remove the transport an SHUTDOWN was last sent to, don't | |
5483 | * do failure management. | |
5484 | */ | |
5485 | if (asoc->shutdown_last_sent_to) | |
5486 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5487 | SCTP_TRANSPORT(asoc->shutdown_last_sent_to)); | |
1da177e4 LT |
5488 | |
5489 | /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for | |
5490 | * the T2-shutdown timer. | |
5491 | */ | |
5492 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5493 | ||
5494 | /* Restart the T2-shutdown timer. */ | |
5495 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5496 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5497 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5498 | return SCTP_DISPOSITION_CONSUME; | |
5499 | ||
5500 | nomem: | |
5501 | return SCTP_DISPOSITION_NOMEM; | |
5502 | } | |
5503 | ||
5504 | /* | |
5505 | * ADDIP Section 4.1 ASCONF CHunk Procedures | |
5506 | * If the T4 RTO timer expires the endpoint should do B1 to B5 | |
5507 | */ | |
5508 | sctp_disposition_t sctp_sf_t4_timer_expire( | |
5509 | const struct sctp_endpoint *ep, | |
5510 | const struct sctp_association *asoc, | |
5511 | const sctp_subtype_t type, | |
5512 | void *arg, | |
5513 | sctp_cmd_seq_t *commands) | |
5514 | { | |
5515 | struct sctp_chunk *chunk = asoc->addip_last_asconf; | |
5516 | struct sctp_transport *transport = chunk->transport; | |
5517 | ||
ac0b0462 SS |
5518 | SCTP_INC_STATS(SCTP_MIB_T4_RTO_EXPIREDS); |
5519 | ||
1da177e4 LT |
5520 | /* ADDIP 4.1 B1) Increment the error counters and perform path failure |
5521 | * detection on the appropriate destination address as defined in | |
5522 | * RFC2960 [5] section 8.1 and 8.2. | |
5523 | */ | |
10a43cea WY |
5524 | if (transport) |
5525 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5526 | SCTP_TRANSPORT(transport)); | |
1da177e4 LT |
5527 | |
5528 | /* Reconfig T4 timer and transport. */ | |
5529 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5530 | ||
5531 | /* ADDIP 4.1 B2) Increment the association error counters and perform | |
5532 | * endpoint failure detection on the association as defined in | |
5533 | * RFC2960 [5] section 8.1 and 8.2. | |
5534 | * association error counter is incremented in SCTP_CMD_STRIKE. | |
5535 | */ | |
5536 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
5537 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5538 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
8de8c873 SS |
5539 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5540 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5541 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5542 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 | 5543 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3d5a019d | 5544 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); |
1da177e4 LT |
5545 | return SCTP_DISPOSITION_ABORT; |
5546 | } | |
5547 | ||
5548 | /* ADDIP 4.1 B3) Back-off the destination address RTO value to which | |
5549 | * the ASCONF chunk was sent by doubling the RTO timer value. | |
5550 | * This is done in SCTP_CMD_STRIKE. | |
5551 | */ | |
5552 | ||
5553 | /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible | |
5554 | * choose an alternate destination address (please refer to RFC2960 | |
5555 | * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this | |
d808ad9a | 5556 | * chunk, it MUST be the same (including its serial number) as the last |
1da177e4 LT |
5557 | * ASCONF sent. |
5558 | */ | |
5559 | sctp_chunk_hold(asoc->addip_last_asconf); | |
5560 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5561 | SCTP_CHUNK(asoc->addip_last_asconf)); | |
5562 | ||
5563 | /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different | |
5564 | * destination is selected, then the RTO used will be that of the new | |
5565 | * destination address. | |
5566 | */ | |
5567 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5568 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5569 | ||
5570 | return SCTP_DISPOSITION_CONSUME; | |
5571 | } | |
5572 | ||
5573 | /* sctpimpguide-05 Section 2.12.2 | |
5574 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5575 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5576 | * At the expiration of this timer the sender SHOULD abort the association | |
5577 | * by sending an ABORT chunk. | |
5578 | */ | |
5579 | sctp_disposition_t sctp_sf_t5_timer_expire(const struct sctp_endpoint *ep, | |
5580 | const struct sctp_association *asoc, | |
5581 | const sctp_subtype_t type, | |
5582 | void *arg, | |
5583 | sctp_cmd_seq_t *commands) | |
5584 | { | |
5585 | struct sctp_chunk *reply = NULL; | |
5586 | ||
5587 | SCTP_DEBUG_PRINTK("Timer T5 expired.\n"); | |
ac0b0462 | 5588 | SCTP_INC_STATS(SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS); |
1da177e4 LT |
5589 | |
5590 | reply = sctp_make_abort(asoc, NULL, 0); | |
5591 | if (!reply) | |
5592 | goto nomem; | |
5593 | ||
5594 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
8de8c873 SS |
5595 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5596 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5597 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5598 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 | 5599 | |
a1080a8b VY |
5600 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5601 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5602 | ||
1da177e4 LT |
5603 | return SCTP_DISPOSITION_DELETE_TCB; |
5604 | nomem: | |
5605 | return SCTP_DISPOSITION_NOMEM; | |
5606 | } | |
5607 | ||
5608 | /* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires, | |
5609 | * the association is automatically closed by starting the shutdown process. | |
5610 | * The work that needs to be done is same as when SHUTDOWN is initiated by | |
5611 | * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown(). | |
5612 | */ | |
5613 | sctp_disposition_t sctp_sf_autoclose_timer_expire( | |
5614 | const struct sctp_endpoint *ep, | |
5615 | const struct sctp_association *asoc, | |
5616 | const sctp_subtype_t type, | |
5617 | void *arg, | |
5618 | sctp_cmd_seq_t *commands) | |
5619 | { | |
5620 | int disposition; | |
5621 | ||
ac0b0462 SS |
5622 | SCTP_INC_STATS(SCTP_MIB_AUTOCLOSE_EXPIREDS); |
5623 | ||
1da177e4 LT |
5624 | /* From 9.2 Shutdown of an Association |
5625 | * Upon receipt of the SHUTDOWN primitive from its upper | |
5626 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
5627 | * remains there until all outstanding data has been | |
5628 | * acknowledged by its peer. The endpoint accepts no new data | |
5629 | * from its upper layer, but retransmits data to the far end | |
5630 | * if necessary to fill gaps. | |
5631 | */ | |
5632 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5633 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
5634 | ||
1da177e4 LT |
5635 | disposition = SCTP_DISPOSITION_CONSUME; |
5636 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
5637 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
5638 | arg, commands); | |
5639 | } | |
5640 | return disposition; | |
5641 | } | |
5642 | ||
5643 | /***************************************************************************** | |
5644 | * These are sa state functions which could apply to all types of events. | |
5645 | ****************************************************************************/ | |
5646 | ||
5647 | /* | |
5648 | * This table entry is not implemented. | |
5649 | * | |
5650 | * Inputs | |
5651 | * (endpoint, asoc, chunk) | |
5652 | * | |
5653 | * The return value is the disposition of the chunk. | |
5654 | */ | |
5655 | sctp_disposition_t sctp_sf_not_impl(const struct sctp_endpoint *ep, | |
5656 | const struct sctp_association *asoc, | |
5657 | const sctp_subtype_t type, | |
5658 | void *arg, | |
5659 | sctp_cmd_seq_t *commands) | |
5660 | { | |
5661 | return SCTP_DISPOSITION_NOT_IMPL; | |
5662 | } | |
5663 | ||
5664 | /* | |
5665 | * This table entry represents a bug. | |
5666 | * | |
5667 | * Inputs | |
5668 | * (endpoint, asoc, chunk) | |
5669 | * | |
5670 | * The return value is the disposition of the chunk. | |
5671 | */ | |
5672 | sctp_disposition_t sctp_sf_bug(const struct sctp_endpoint *ep, | |
5673 | const struct sctp_association *asoc, | |
5674 | const sctp_subtype_t type, | |
5675 | void *arg, | |
5676 | sctp_cmd_seq_t *commands) | |
5677 | { | |
5678 | return SCTP_DISPOSITION_BUG; | |
5679 | } | |
5680 | ||
5681 | /* | |
5682 | * This table entry represents the firing of a timer in the wrong state. | |
5683 | * Since timer deletion cannot be guaranteed a timer 'may' end up firing | |
5684 | * when the association is in the wrong state. This event should | |
5685 | * be ignored, so as to prevent any rearming of the timer. | |
5686 | * | |
5687 | * Inputs | |
5688 | * (endpoint, asoc, chunk) | |
5689 | * | |
5690 | * The return value is the disposition of the chunk. | |
5691 | */ | |
5692 | sctp_disposition_t sctp_sf_timer_ignore(const struct sctp_endpoint *ep, | |
5693 | const struct sctp_association *asoc, | |
5694 | const sctp_subtype_t type, | |
5695 | void *arg, | |
5696 | sctp_cmd_seq_t *commands) | |
5697 | { | |
5698 | SCTP_DEBUG_PRINTK("Timer %d ignored.\n", type.chunk); | |
5699 | return SCTP_DISPOSITION_CONSUME; | |
5700 | } | |
5701 | ||
5702 | /******************************************************************** | |
5703 | * 2nd Level Abstractions | |
5704 | ********************************************************************/ | |
5705 | ||
5706 | /* Pull the SACK chunk based on the SACK header. */ | |
5707 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk) | |
5708 | { | |
5709 | struct sctp_sackhdr *sack; | |
5710 | unsigned int len; | |
5711 | __u16 num_blocks; | |
5712 | __u16 num_dup_tsns; | |
5713 | ||
5714 | /* Protect ourselves from reading too far into | |
5715 | * the skb from a bogus sender. | |
5716 | */ | |
5717 | sack = (struct sctp_sackhdr *) chunk->skb->data; | |
5718 | ||
5719 | num_blocks = ntohs(sack->num_gap_ack_blocks); | |
5720 | num_dup_tsns = ntohs(sack->num_dup_tsns); | |
5721 | len = sizeof(struct sctp_sackhdr); | |
5722 | len += (num_blocks + num_dup_tsns) * sizeof(__u32); | |
5723 | if (len > chunk->skb->len) | |
5724 | return NULL; | |
5725 | ||
5726 | skb_pull(chunk->skb, len); | |
5727 | ||
5728 | return sack; | |
5729 | } | |
5730 | ||
5731 | /* Create an ABORT packet to be sent as a response, with the specified | |
5732 | * error causes. | |
5733 | */ | |
5734 | static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep, | |
5735 | const struct sctp_association *asoc, | |
5736 | struct sctp_chunk *chunk, | |
5737 | const void *payload, | |
5738 | size_t paylen) | |
5739 | { | |
5740 | struct sctp_packet *packet; | |
5741 | struct sctp_chunk *abort; | |
5742 | ||
5743 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5744 | ||
5745 | if (packet) { | |
5746 | /* Make an ABORT. | |
5747 | * The T bit will be set if the asoc is NULL. | |
5748 | */ | |
5749 | abort = sctp_make_abort(asoc, chunk, paylen); | |
5750 | if (!abort) { | |
5751 | sctp_ootb_pkt_free(packet); | |
5752 | return NULL; | |
5753 | } | |
047a2428 JF |
5754 | |
5755 | /* Reflect vtag if T-Bit is set */ | |
5756 | if (sctp_test_T_bit(abort)) | |
5757 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
5758 | ||
1da177e4 LT |
5759 | /* Add specified error causes, i.e., payload, to the |
5760 | * end of the chunk. | |
5761 | */ | |
5762 | sctp_addto_chunk(abort, paylen, payload); | |
5763 | ||
5764 | /* Set the skb to the belonging sock for accounting. */ | |
5765 | abort->skb->sk = ep->base.sk; | |
5766 | ||
5767 | sctp_packet_append_chunk(packet, abort); | |
5768 | ||
5769 | } | |
5770 | ||
5771 | return packet; | |
5772 | } | |
5773 | ||
5774 | /* Allocate a packet for responding in the OOTB conditions. */ | |
5775 | static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc, | |
5776 | const struct sctp_chunk *chunk) | |
5777 | { | |
5778 | struct sctp_packet *packet; | |
5779 | struct sctp_transport *transport; | |
5780 | __u16 sport; | |
5781 | __u16 dport; | |
5782 | __u32 vtag; | |
5783 | ||
5784 | /* Get the source and destination port from the inbound packet. */ | |
5785 | sport = ntohs(chunk->sctp_hdr->dest); | |
5786 | dport = ntohs(chunk->sctp_hdr->source); | |
5787 | ||
5788 | /* The V-tag is going to be the same as the inbound packet if no | |
5789 | * association exists, otherwise, use the peer's vtag. | |
5790 | */ | |
5791 | if (asoc) { | |
02c4e12c WY |
5792 | /* Special case the INIT-ACK as there is no peer's vtag |
5793 | * yet. | |
5794 | */ | |
5795 | switch(chunk->chunk_hdr->type) { | |
5796 | case SCTP_CID_INIT_ACK: | |
5797 | { | |
5798 | sctp_initack_chunk_t *initack; | |
5799 | ||
5800 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
5801 | vtag = ntohl(initack->init_hdr.init_tag); | |
5802 | break; | |
5803 | } | |
5804 | default: | |
5805 | vtag = asoc->peer.i.init_tag; | |
5806 | break; | |
5807 | } | |
1da177e4 LT |
5808 | } else { |
5809 | /* Special case the INIT and stale COOKIE_ECHO as there is no | |
5810 | * vtag yet. | |
5811 | */ | |
5812 | switch(chunk->chunk_hdr->type) { | |
5813 | case SCTP_CID_INIT: | |
5814 | { | |
5815 | sctp_init_chunk_t *init; | |
5816 | ||
5817 | init = (sctp_init_chunk_t *)chunk->chunk_hdr; | |
5818 | vtag = ntohl(init->init_hdr.init_tag); | |
5819 | break; | |
5820 | } | |
d808ad9a | 5821 | default: |
1da177e4 LT |
5822 | vtag = ntohl(chunk->sctp_hdr->vtag); |
5823 | break; | |
5824 | } | |
5825 | } | |
5826 | ||
5827 | /* Make a transport for the bucket, Eliza... */ | |
6a1e5f33 | 5828 | transport = sctp_transport_new(sctp_source(chunk), GFP_ATOMIC); |
1da177e4 LT |
5829 | if (!transport) |
5830 | goto nomem; | |
5831 | ||
5832 | /* Cache a route for the transport with the chunk's destination as | |
5833 | * the source address. | |
5834 | */ | |
16b0a030 | 5835 | sctp_transport_route(transport, (union sctp_addr *)&chunk->dest, |
1da177e4 LT |
5836 | sctp_sk(sctp_get_ctl_sock())); |
5837 | ||
5838 | packet = sctp_packet_init(&transport->packet, transport, sport, dport); | |
5839 | packet = sctp_packet_config(packet, vtag, 0); | |
5840 | ||
5841 | return packet; | |
5842 | ||
5843 | nomem: | |
5844 | return NULL; | |
5845 | } | |
5846 | ||
5847 | /* Free the packet allocated earlier for responding in the OOTB condition. */ | |
5848 | void sctp_ootb_pkt_free(struct sctp_packet *packet) | |
5849 | { | |
5850 | sctp_transport_free(packet->transport); | |
5851 | } | |
5852 | ||
5853 | /* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */ | |
5854 | static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep, | |
5855 | const struct sctp_association *asoc, | |
5856 | const struct sctp_chunk *chunk, | |
5857 | sctp_cmd_seq_t *commands, | |
5858 | struct sctp_chunk *err_chunk) | |
5859 | { | |
5860 | struct sctp_packet *packet; | |
5861 | ||
5862 | if (err_chunk) { | |
5863 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5864 | if (packet) { | |
5865 | struct sctp_signed_cookie *cookie; | |
5866 | ||
5867 | /* Override the OOTB vtag from the cookie. */ | |
5868 | cookie = chunk->subh.cookie_hdr; | |
5869 | packet->vtag = cookie->c.peer_vtag; | |
d808ad9a | 5870 | |
1da177e4 LT |
5871 | /* Set the skb to the belonging sock for accounting. */ |
5872 | err_chunk->skb->sk = ep->base.sk; | |
5873 | sctp_packet_append_chunk(packet, err_chunk); | |
5874 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
5875 | SCTP_PACKET(packet)); | |
5876 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
5877 | } else | |
5878 | sctp_chunk_free (err_chunk); | |
5879 | } | |
5880 | } | |
5881 | ||
5882 | ||
5883 | /* Process a data chunk */ | |
5884 | static int sctp_eat_data(const struct sctp_association *asoc, | |
5885 | struct sctp_chunk *chunk, | |
5886 | sctp_cmd_seq_t *commands) | |
5887 | { | |
5888 | sctp_datahdr_t *data_hdr; | |
5889 | struct sctp_chunk *err; | |
5890 | size_t datalen; | |
5891 | sctp_verb_t deliver; | |
5892 | int tmp; | |
5893 | __u32 tsn; | |
7c3ceb4f | 5894 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
049b3ff5 | 5895 | struct sock *sk = asoc->base.sk; |
f1751c57 VY |
5896 | u16 ssn; |
5897 | u16 sid; | |
5898 | u8 ordered = 0; | |
1da177e4 LT |
5899 | |
5900 | data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data; | |
5901 | skb_pull(chunk->skb, sizeof(sctp_datahdr_t)); | |
5902 | ||
5903 | tsn = ntohl(data_hdr->tsn); | |
5904 | SCTP_DEBUG_PRINTK("eat_data: TSN 0x%x.\n", tsn); | |
5905 | ||
5906 | /* ASSERT: Now skb->data is really the user data. */ | |
5907 | ||
5908 | /* Process ECN based congestion. | |
5909 | * | |
5910 | * Since the chunk structure is reused for all chunks within | |
5911 | * a packet, we use ecn_ce_done to track if we've already | |
5912 | * done CE processing for this packet. | |
5913 | * | |
5914 | * We need to do ECN processing even if we plan to discard the | |
5915 | * chunk later. | |
5916 | */ | |
5917 | ||
5918 | if (!chunk->ecn_ce_done) { | |
5919 | struct sctp_af *af; | |
5920 | chunk->ecn_ce_done = 1; | |
5921 | ||
5922 | af = sctp_get_af_specific( | |
eddc9ec5 | 5923 | ipver2af(ip_hdr(chunk->skb)->version)); |
1da177e4 LT |
5924 | |
5925 | if (af && af->is_ce(chunk->skb) && asoc->peer.ecn_capable) { | |
5926 | /* Do real work as sideffect. */ | |
5927 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE, | |
5928 | SCTP_U32(tsn)); | |
5929 | } | |
5930 | } | |
5931 | ||
5932 | tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn); | |
5933 | if (tmp < 0) { | |
5934 | /* The TSN is too high--silently discard the chunk and | |
5935 | * count on it getting retransmitted later. | |
5936 | */ | |
5937 | return SCTP_IERROR_HIGH_TSN; | |
5938 | } else if (tmp > 0) { | |
5939 | /* This is a duplicate. Record it. */ | |
5940 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn)); | |
5941 | return SCTP_IERROR_DUP_TSN; | |
5942 | } | |
5943 | ||
5944 | /* This is a new TSN. */ | |
5945 | ||
5946 | /* Discard if there is no room in the receive window. | |
5947 | * Actually, allow a little bit of overflow (up to a MTU). | |
5948 | */ | |
5949 | datalen = ntohs(chunk->chunk_hdr->length); | |
5950 | datalen -= sizeof(sctp_data_chunk_t); | |
5951 | ||
5952 | deliver = SCTP_CMD_CHUNK_ULP; | |
5953 | ||
5954 | /* Think about partial delivery. */ | |
5955 | if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) { | |
5956 | ||
5957 | /* Even if we don't accept this chunk there is | |
5958 | * memory pressure. | |
5959 | */ | |
5960 | sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL()); | |
5961 | } | |
5962 | ||
d808ad9a | 5963 | /* Spill over rwnd a little bit. Note: While allowed, this spill over |
1da177e4 LT |
5964 | * seems a bit troublesome in that frag_point varies based on |
5965 | * PMTU. In cases, such as loopback, this might be a rather | |
5966 | * large spill over. | |
4d93df0a NH |
5967 | */ |
5968 | if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over || | |
5969 | (datalen > asoc->rwnd + asoc->frag_point))) { | |
1da177e4 LT |
5970 | |
5971 | /* If this is the next TSN, consider reneging to make | |
5972 | * room. Note: Playing nice with a confused sender. A | |
5973 | * malicious sender can still eat up all our buffer | |
5974 | * space and in the future we may want to detect and | |
5975 | * do more drastic reneging. | |
5976 | */ | |
7c3ceb4f NH |
5977 | if (sctp_tsnmap_has_gap(map) && |
5978 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
1da177e4 LT |
5979 | SCTP_DEBUG_PRINTK("Reneging for tsn:%u\n", tsn); |
5980 | deliver = SCTP_CMD_RENEGE; | |
5981 | } else { | |
5982 | SCTP_DEBUG_PRINTK("Discard tsn: %u len: %Zd, " | |
5983 | "rwnd: %d\n", tsn, datalen, | |
5984 | asoc->rwnd); | |
5985 | return SCTP_IERROR_IGNORE_TSN; | |
5986 | } | |
5987 | } | |
5988 | ||
4d93df0a NH |
5989 | /* |
5990 | * Also try to renege to limit our memory usage in the event that | |
5991 | * we are under memory pressure | |
3ab224be | 5992 | * If we can't renege, don't worry about it, the sk_rmem_schedule |
4d93df0a NH |
5993 | * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our |
5994 | * memory usage too much | |
5995 | */ | |
5996 | if (*sk->sk_prot_creator->memory_pressure) { | |
5997 | if (sctp_tsnmap_has_gap(map) && | |
5998 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
5999 | SCTP_DEBUG_PRINTK("Under Pressure! Reneging for tsn:%u\n", tsn); | |
6000 | deliver = SCTP_CMD_RENEGE; | |
6001 | } | |
6002 | } | |
6003 | ||
1da177e4 LT |
6004 | /* |
6005 | * Section 3.3.10.9 No User Data (9) | |
6006 | * | |
6007 | * Cause of error | |
6008 | * --------------- | |
6009 | * No User Data: This error cause is returned to the originator of a | |
6010 | * DATA chunk if a received DATA chunk has no user data. | |
6011 | */ | |
6012 | if (unlikely(0 == datalen)) { | |
6013 | err = sctp_make_abort_no_data(asoc, chunk, tsn); | |
6014 | if (err) { | |
6015 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6016 | SCTP_CHUNK(err)); | |
6017 | } | |
6018 | /* We are going to ABORT, so we might as well stop | |
6019 | * processing the rest of the chunks in the packet. | |
6020 | */ | |
6021 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 SS |
6022 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
6023 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 | 6024 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 6025 | SCTP_PERR(SCTP_ERROR_NO_DATA)); |
1da177e4 LT |
6026 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
6027 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
6028 | return SCTP_IERROR_NO_DATA; | |
6029 | } | |
6030 | ||
9faa730f SS |
6031 | chunk->data_accepted = 1; |
6032 | ||
1da177e4 LT |
6033 | /* Note: Some chunks may get overcounted (if we drop) or overcounted |
6034 | * if we renege and the chunk arrives again. | |
6035 | */ | |
6036 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) | |
6037 | SCTP_INC_STATS(SCTP_MIB_INUNORDERCHUNKS); | |
f1751c57 | 6038 | else { |
1da177e4 | 6039 | SCTP_INC_STATS(SCTP_MIB_INORDERCHUNKS); |
f1751c57 VY |
6040 | ordered = 1; |
6041 | } | |
1da177e4 LT |
6042 | |
6043 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
6044 | * | |
6045 | * If an endpoint receive a DATA chunk with an invalid stream | |
6046 | * identifier, it shall acknowledge the reception of the DATA chunk | |
6047 | * following the normal procedure, immediately send an ERROR chunk | |
6048 | * with cause set to "Invalid Stream Identifier" (See Section 3.3.10) | |
6049 | * and discard the DATA chunk. | |
6050 | */ | |
f1751c57 VY |
6051 | sid = ntohs(data_hdr->stream); |
6052 | if (sid >= asoc->c.sinit_max_instreams) { | |
3888e9ef VY |
6053 | /* Mark tsn as received even though we drop it */ |
6054 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn)); | |
6055 | ||
1da177e4 LT |
6056 | err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM, |
6057 | &data_hdr->stream, | |
6383cfb3 VY |
6058 | sizeof(data_hdr->stream), |
6059 | sizeof(u16)); | |
1da177e4 LT |
6060 | if (err) |
6061 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
6062 | SCTP_CHUNK(err)); | |
6063 | return SCTP_IERROR_BAD_STREAM; | |
6064 | } | |
6065 | ||
f1751c57 VY |
6066 | /* Check to see if the SSN is possible for this TSN. |
6067 | * The biggest gap we can record is 4K wide. Since SSNs wrap | |
6068 | * at an unsigned short, there is no way that an SSN can | |
6069 | * wrap and for a valid TSN. We can simply check if the current | |
6070 | * SSN is smaller then the next expected one. If it is, it wrapped | |
6071 | * and is invalid. | |
6072 | */ | |
6073 | ssn = ntohs(data_hdr->ssn); | |
6074 | if (ordered && SSN_lt(ssn, sctp_ssn_peek(&asoc->ssnmap->in, sid))) { | |
6075 | return SCTP_IERROR_PROTO_VIOLATION; | |
6076 | } | |
6077 | ||
1da177e4 LT |
6078 | /* Send the data up to the user. Note: Schedule the |
6079 | * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK | |
6080 | * chunk needs the updated rwnd. | |
6081 | */ | |
6082 | sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk)); | |
6083 | ||
6084 | return SCTP_IERROR_NO_ERROR; | |
6085 | } |