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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 | ||
337 | /* Verify the INIT chunk before processing it. */ | |
338 | err_chunk = NULL; | |
339 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
340 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
341 | &err_chunk)) { | |
342 | /* This chunk contains fatal error. It is to be discarded. | |
343 | * Send an ABORT, with causes if there is any. | |
344 | */ | |
345 | if (err_chunk) { | |
346 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
347 | (__u8 *)(err_chunk->chunk_hdr) + | |
348 | sizeof(sctp_chunkhdr_t), | |
349 | ntohs(err_chunk->chunk_hdr->length) - | |
350 | sizeof(sctp_chunkhdr_t)); | |
351 | ||
352 | sctp_chunk_free(err_chunk); | |
353 | ||
354 | if (packet) { | |
355 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
356 | SCTP_PACKET(packet)); | |
357 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
358 | return SCTP_DISPOSITION_CONSUME; | |
359 | } else { | |
360 | return SCTP_DISPOSITION_NOMEM; | |
361 | } | |
362 | } else { | |
363 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
364 | commands); | |
365 | } | |
366 | } | |
367 | ||
d808ad9a | 368 | /* Grab the INIT header. */ |
1da177e4 LT |
369 | chunk->subh.init_hdr = (sctp_inithdr_t *)chunk->skb->data; |
370 | ||
371 | /* Tag the variable length parameters. */ | |
372 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
373 | ||
374 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
375 | if (!new_asoc) | |
376 | goto nomem; | |
377 | ||
378 | /* The call, sctp_process_init(), can fail on memory allocation. */ | |
379 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
380 | sctp_source(chunk), | |
381 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
382 | GFP_ATOMIC)) | |
383 | goto nomem_init; | |
384 | ||
1da177e4 LT |
385 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ |
386 | ||
387 | /* If there are errors need to be reported for unknown parameters, | |
388 | * make sure to reserve enough room in the INIT ACK for them. | |
389 | */ | |
390 | len = 0; | |
391 | if (err_chunk) | |
392 | len = ntohs(err_chunk->chunk_hdr->length) - | |
393 | sizeof(sctp_chunkhdr_t); | |
394 | ||
395 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0) | |
df7deeb5 | 396 | goto nomem_init; |
1da177e4 LT |
397 | |
398 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); | |
399 | if (!repl) | |
df7deeb5 | 400 | goto nomem_init; |
1da177e4 LT |
401 | |
402 | /* If there are errors need to be reported for unknown parameters, | |
403 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
404 | * parameter. | |
405 | */ | |
406 | if (err_chunk) { | |
407 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
408 | * ERROR chunk generated by sctp_verify_init(). Since the | |
409 | * error cause code for "unknown parameter" and the | |
410 | * "Unrecognized parameter" type is the same, we can | |
411 | * construct the parameters in INIT ACK by copying the | |
412 | * ERROR causes over. | |
413 | */ | |
414 | unk_param = (sctp_unrecognized_param_t *) | |
415 | ((__u8 *)(err_chunk->chunk_hdr) + | |
416 | sizeof(sctp_chunkhdr_t)); | |
417 | /* Replace the cause code with the "Unrecognized parameter" | |
418 | * parameter type. | |
419 | */ | |
420 | sctp_addto_chunk(repl, len, unk_param); | |
421 | sctp_chunk_free(err_chunk); | |
422 | } | |
423 | ||
df7deeb5 VY |
424 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); |
425 | ||
1da177e4 LT |
426 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
427 | ||
428 | /* | |
429 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
430 | * "Z" MUST NOT allocate any resources, nor keep any states for the | |
431 | * new association. Otherwise, "Z" will be vulnerable to resource | |
432 | * attacks. | |
433 | */ | |
434 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
435 | ||
436 | return SCTP_DISPOSITION_DELETE_TCB; | |
437 | ||
1da177e4 LT |
438 | nomem_init: |
439 | sctp_association_free(new_asoc); | |
440 | nomem: | |
df7deeb5 VY |
441 | if (err_chunk) |
442 | sctp_chunk_free(err_chunk); | |
1da177e4 LT |
443 | return SCTP_DISPOSITION_NOMEM; |
444 | } | |
445 | ||
446 | /* | |
447 | * Respond to a normal INIT ACK chunk. | |
448 | * We are the side that is initiating the association. | |
449 | * | |
450 | * Section: 5.1 Normal Establishment of an Association, C | |
451 | * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init | |
452 | * timer and leave COOKIE-WAIT state. "A" shall then send the State | |
453 | * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start | |
454 | * the T1-cookie timer, and enter the COOKIE-ECHOED state. | |
455 | * | |
456 | * Note: The COOKIE ECHO chunk can be bundled with any pending outbound | |
457 | * DATA chunks, but it MUST be the first chunk in the packet and | |
458 | * until the COOKIE ACK is returned the sender MUST NOT send any | |
459 | * other packets to the peer. | |
460 | * | |
461 | * Verification Tag: 3.3.3 | |
462 | * If the value of the Initiate Tag in a received INIT ACK chunk is | |
463 | * found to be 0, the receiver MUST treat it as an error and close the | |
464 | * association by transmitting an ABORT. | |
465 | * | |
466 | * Inputs | |
467 | * (endpoint, asoc, chunk) | |
468 | * | |
469 | * Outputs | |
470 | * (asoc, reply_msg, msg_up, timers, counters) | |
471 | * | |
472 | * The return value is the disposition of the chunk. | |
473 | */ | |
474 | sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, | |
475 | const struct sctp_association *asoc, | |
476 | const sctp_subtype_t type, | |
477 | void *arg, | |
478 | sctp_cmd_seq_t *commands) | |
479 | { | |
480 | struct sctp_chunk *chunk = arg; | |
481 | sctp_init_chunk_t *initchunk; | |
1da177e4 LT |
482 | struct sctp_chunk *err_chunk; |
483 | struct sctp_packet *packet; | |
1da177e4 LT |
484 | |
485 | if (!sctp_vtag_verify(chunk, asoc)) | |
486 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
487 | ||
1da177e4 LT |
488 | /* 6.10 Bundling |
489 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
490 | * SHUTDOWN COMPLETE with any other chunks. | |
491 | */ | |
492 | if (!chunk->singleton) | |
ece25dfa | 493 | return sctp_sf_violation_chunk(ep, asoc, type, arg, commands); |
1da177e4 | 494 | |
ece25dfa VY |
495 | /* Make sure that the INIT-ACK chunk has a valid length */ |
496 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_initack_chunk_t))) | |
497 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
498 | commands); | |
1da177e4 LT |
499 | /* Grab the INIT header. */ |
500 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
501 | ||
1da177e4 LT |
502 | /* Verify the INIT chunk before processing it. */ |
503 | err_chunk = NULL; | |
504 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
505 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
506 | &err_chunk)) { | |
507 | ||
853f4b50 VY |
508 | sctp_error_t error = SCTP_ERROR_NO_RESOURCE; |
509 | ||
1da177e4 | 510 | /* This chunk contains fatal error. It is to be discarded. |
d6701191 VY |
511 | * Send an ABORT, with causes. If there are no causes, |
512 | * then there wasn't enough memory. Just terminate | |
513 | * the association. | |
1da177e4 LT |
514 | */ |
515 | if (err_chunk) { | |
516 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
517 | (__u8 *)(err_chunk->chunk_hdr) + | |
518 | sizeof(sctp_chunkhdr_t), | |
519 | ntohs(err_chunk->chunk_hdr->length) - | |
520 | sizeof(sctp_chunkhdr_t)); | |
521 | ||
522 | sctp_chunk_free(err_chunk); | |
523 | ||
524 | if (packet) { | |
525 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
526 | SCTP_PACKET(packet)); | |
527 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
8de8c873 | 528 | error = SCTP_ERROR_INV_PARAM; |
1da177e4 | 529 | } |
1da177e4 | 530 | } |
bbd0d598 VY |
531 | |
532 | /* SCTP-AUTH, Section 6.3: | |
533 | * It should be noted that if the receiver wants to tear | |
534 | * down an association in an authenticated way only, the | |
535 | * handling of malformed packets should not result in | |
536 | * tearing down the association. | |
537 | * | |
538 | * This means that if we only want to abort associations | |
539 | * in an authenticated way (i.e AUTH+ABORT), then we | |
ac461a03 | 540 | * can't destroy this association just becuase the packet |
bbd0d598 VY |
541 | * was malformed. |
542 | */ | |
543 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
544 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
545 | ||
546 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
8de8c873 SS |
547 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, |
548 | asoc, chunk->transport); | |
1da177e4 LT |
549 | } |
550 | ||
551 | /* Tag the variable length parameters. Note that we never | |
552 | * convert the parameters in an INIT chunk. | |
553 | */ | |
554 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
555 | ||
556 | initchunk = (sctp_init_chunk_t *) chunk->chunk_hdr; | |
557 | ||
558 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT, | |
559 | SCTP_PEER_INIT(initchunk)); | |
560 | ||
3f7a87d2 FF |
561 | /* Reset init error count upon receipt of INIT-ACK. */ |
562 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); | |
563 | ||
1da177e4 LT |
564 | /* 5.1 C) "A" shall stop the T1-init timer and leave |
565 | * COOKIE-WAIT state. "A" shall then ... start the T1-cookie | |
566 | * timer, and enter the COOKIE-ECHOED state. | |
567 | */ | |
568 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
569 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
570 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
571 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
572 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
573 | SCTP_STATE(SCTP_STATE_COOKIE_ECHOED)); | |
574 | ||
730fc3d0 VY |
575 | /* SCTP-AUTH: genereate the assocition shared keys so that |
576 | * we can potentially signe the COOKIE-ECHO. | |
577 | */ | |
578 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_SHKEY, SCTP_NULL()); | |
579 | ||
1da177e4 LT |
580 | /* 5.1 C) "A" shall then send the State Cookie received in the |
581 | * INIT ACK chunk in a COOKIE ECHO chunk, ... | |
582 | */ | |
583 | /* If there is any errors to report, send the ERROR chunk generated | |
584 | * for unknown parameters as well. | |
585 | */ | |
586 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO, | |
587 | SCTP_CHUNK(err_chunk)); | |
588 | ||
589 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
590 | } |
591 | ||
592 | /* | |
593 | * Respond to a normal COOKIE ECHO chunk. | |
594 | * We are the side that is being asked for an association. | |
595 | * | |
596 | * Section: 5.1 Normal Establishment of an Association, D | |
597 | * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply | |
598 | * with a COOKIE ACK chunk after building a TCB and moving to | |
599 | * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with | |
600 | * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK | |
601 | * chunk MUST be the first chunk in the packet. | |
602 | * | |
603 | * IMPLEMENTATION NOTE: An implementation may choose to send the | |
604 | * Communication Up notification to the SCTP user upon reception | |
605 | * of a valid COOKIE ECHO chunk. | |
606 | * | |
607 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
608 | * D) Rules for packet carrying a COOKIE ECHO | |
609 | * | |
610 | * - When sending a COOKIE ECHO, the endpoint MUST use the value of the | |
611 | * Initial Tag received in the INIT ACK. | |
612 | * | |
613 | * - The receiver of a COOKIE ECHO follows the procedures in Section 5. | |
614 | * | |
615 | * Inputs | |
616 | * (endpoint, asoc, chunk) | |
617 | * | |
618 | * Outputs | |
619 | * (asoc, reply_msg, msg_up, timers, counters) | |
620 | * | |
621 | * The return value is the disposition of the chunk. | |
622 | */ | |
623 | sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep, | |
624 | const struct sctp_association *asoc, | |
625 | const sctp_subtype_t type, void *arg, | |
626 | sctp_cmd_seq_t *commands) | |
627 | { | |
628 | struct sctp_chunk *chunk = arg; | |
629 | struct sctp_association *new_asoc; | |
630 | sctp_init_chunk_t *peer_init; | |
631 | struct sctp_chunk *repl; | |
df7deeb5 | 632 | struct sctp_ulpevent *ev, *ai_ev = NULL; |
1da177e4 LT |
633 | int error = 0; |
634 | struct sctp_chunk *err_chk_p; | |
609ee467 | 635 | struct sock *sk; |
1da177e4 LT |
636 | |
637 | /* If the packet is an OOTB packet which is temporarily on the | |
638 | * control endpoint, respond with an ABORT. | |
639 | */ | |
8190f89d WY |
640 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) { |
641 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
ece25dfa | 642 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
8190f89d | 643 | } |
1da177e4 LT |
644 | |
645 | /* Make sure that the COOKIE_ECHO chunk has a valid length. | |
646 | * In this case, we check that we have enough for at least a | |
647 | * chunk header. More detailed verification is done | |
648 | * in sctp_unpack_cookie(). | |
649 | */ | |
650 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
651 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
652 | ||
609ee467 VY |
653 | /* If the endpoint is not listening or if the number of associations |
654 | * on the TCP-style socket exceed the max backlog, respond with an | |
655 | * ABORT. | |
656 | */ | |
657 | sk = ep->base.sk; | |
658 | if (!sctp_sstate(sk, LISTENING) || | |
659 | (sctp_style(sk, TCP) && sk_acceptq_is_full(sk))) | |
660 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
661 | ||
1da177e4 LT |
662 | /* "Decode" the chunk. We have no optional parameters so we |
663 | * are in good shape. | |
664 | */ | |
d808ad9a | 665 | chunk->subh.cookie_hdr = |
1da177e4 | 666 | (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
667 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
668 | sizeof(sctp_chunkhdr_t))) | |
669 | goto nomem; | |
1da177e4 LT |
670 | |
671 | /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint | |
672 | * "Z" will reply with a COOKIE ACK chunk after building a TCB | |
673 | * and moving to the ESTABLISHED state. | |
674 | */ | |
675 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
676 | &err_chk_p); | |
677 | ||
678 | /* FIXME: | |
679 | * If the re-build failed, what is the proper error path | |
680 | * from here? | |
681 | * | |
682 | * [We should abort the association. --piggy] | |
683 | */ | |
684 | if (!new_asoc) { | |
685 | /* FIXME: Several errors are possible. A bad cookie should | |
686 | * be silently discarded, but think about logging it too. | |
687 | */ | |
688 | switch (error) { | |
689 | case -SCTP_IERROR_NOMEM: | |
690 | goto nomem; | |
691 | ||
692 | case -SCTP_IERROR_STALE_COOKIE: | |
693 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
694 | err_chk_p); | |
695 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
696 | ||
697 | case -SCTP_IERROR_BAD_SIG: | |
698 | default: | |
699 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 700 | } |
1da177e4 LT |
701 | } |
702 | ||
1da177e4 | 703 | |
df7deeb5 VY |
704 | /* Delay state machine commands until later. |
705 | * | |
706 | * Re-build the bind address for the association is done in | |
1da177e4 LT |
707 | * the sctp_unpack_cookie() already. |
708 | */ | |
709 | /* This is a brand-new association, so these are not yet side | |
710 | * effects--it is safe to run them here. | |
711 | */ | |
712 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
713 | ||
714 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
6a1e5f33 | 715 | &chunk->subh.cookie_hdr->c.peer_addr, |
1da177e4 LT |
716 | peer_init, GFP_ATOMIC)) |
717 | goto nomem_init; | |
718 | ||
730fc3d0 VY |
719 | /* SCTP-AUTH: Now that we've populate required fields in |
720 | * sctp_process_init, set up the assocaition shared keys as | |
721 | * necessary so that we can potentially authenticate the ACK | |
722 | */ | |
723 | error = sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC); | |
724 | if (error) | |
725 | goto nomem_init; | |
726 | ||
bbd0d598 VY |
727 | /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo |
728 | * is supposed to be authenticated and we have to do delayed | |
729 | * authentication. We've just recreated the association using | |
730 | * the information in the cookie and now it's much easier to | |
731 | * do the authentication. | |
732 | */ | |
733 | if (chunk->auth_chunk) { | |
734 | struct sctp_chunk auth; | |
735 | sctp_ierror_t ret; | |
736 | ||
737 | /* set-up our fake chunk so that we can process it */ | |
738 | auth.skb = chunk->auth_chunk; | |
739 | auth.asoc = chunk->asoc; | |
740 | auth.sctp_hdr = chunk->sctp_hdr; | |
741 | auth.chunk_hdr = (sctp_chunkhdr_t *)skb_push(chunk->auth_chunk, | |
742 | sizeof(sctp_chunkhdr_t)); | |
743 | skb_pull(chunk->auth_chunk, sizeof(sctp_chunkhdr_t)); | |
744 | auth.transport = chunk->transport; | |
745 | ||
746 | ret = sctp_sf_authenticate(ep, new_asoc, type, &auth); | |
747 | ||
748 | /* We can now safely free the auth_chunk clone */ | |
749 | kfree_skb(chunk->auth_chunk); | |
750 | ||
751 | if (ret != SCTP_IERROR_NO_ERROR) { | |
752 | sctp_association_free(new_asoc); | |
753 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
754 | } | |
755 | } | |
756 | ||
1da177e4 LT |
757 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
758 | if (!repl) | |
df7deeb5 | 759 | goto nomem_init; |
1da177e4 LT |
760 | |
761 | /* RFC 2960 5.1 Normal Establishment of an Association | |
762 | * | |
763 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
764 | * send the Communication Up notification to the SCTP user | |
765 | * upon reception of a valid COOKIE ECHO chunk. | |
766 | */ | |
767 | ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0, | |
768 | new_asoc->c.sinit_num_ostreams, | |
769 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 770 | NULL, GFP_ATOMIC); |
1da177e4 LT |
771 | if (!ev) |
772 | goto nomem_ev; | |
773 | ||
d808ad9a | 774 | /* Sockets API Draft Section 5.3.1.6 |
0f3fffd8 | 775 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 776 | * delivers this notification to inform the application that of the |
0f3fffd8 | 777 | * peers requested adaptation layer. |
1da177e4 | 778 | */ |
0f3fffd8 ISJ |
779 | if (new_asoc->peer.adaptation_ind) { |
780 | ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc, | |
1da177e4 | 781 | GFP_ATOMIC); |
df7deeb5 VY |
782 | if (!ai_ev) |
783 | goto nomem_aiev; | |
784 | } | |
785 | ||
786 | /* Add all the state machine commands now since we've created | |
787 | * everything. This way we don't introduce memory corruptions | |
788 | * during side-effect processing and correclty count established | |
789 | * associations. | |
790 | */ | |
791 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
792 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
793 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
794 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
795 | SCTP_INC_STATS(SCTP_MIB_PASSIVEESTABS); | |
796 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
797 | ||
798 | if (new_asoc->autoclose) | |
799 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
800 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
801 | ||
df7deeb5 VY |
802 | /* This will send the COOKIE ACK */ |
803 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
804 | ||
805 | /* Queue the ASSOC_CHANGE event */ | |
806 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
807 | ||
808 | /* Send up the Adaptation Layer Indication event */ | |
809 | if (ai_ev) | |
1da177e4 | 810 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
df7deeb5 | 811 | SCTP_ULPEVENT(ai_ev)); |
1da177e4 LT |
812 | |
813 | return SCTP_DISPOSITION_CONSUME; | |
814 | ||
df7deeb5 VY |
815 | nomem_aiev: |
816 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
817 | nomem_ev: |
818 | sctp_chunk_free(repl); | |
1da177e4 LT |
819 | nomem_init: |
820 | sctp_association_free(new_asoc); | |
821 | nomem: | |
822 | return SCTP_DISPOSITION_NOMEM; | |
823 | } | |
824 | ||
825 | /* | |
826 | * Respond to a normal COOKIE ACK chunk. | |
827 | * We are the side that is being asked for an association. | |
828 | * | |
829 | * RFC 2960 5.1 Normal Establishment of an Association | |
830 | * | |
831 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the | |
832 | * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie | |
833 | * timer. It may also notify its ULP about the successful | |
834 | * establishment of the association with a Communication Up | |
835 | * notification (see Section 10). | |
836 | * | |
837 | * Verification Tag: | |
838 | * Inputs | |
839 | * (endpoint, asoc, chunk) | |
840 | * | |
841 | * Outputs | |
842 | * (asoc, reply_msg, msg_up, timers, counters) | |
843 | * | |
844 | * The return value is the disposition of the chunk. | |
845 | */ | |
846 | sctp_disposition_t sctp_sf_do_5_1E_ca(const struct sctp_endpoint *ep, | |
847 | const struct sctp_association *asoc, | |
848 | const sctp_subtype_t type, void *arg, | |
849 | sctp_cmd_seq_t *commands) | |
850 | { | |
851 | struct sctp_chunk *chunk = arg; | |
852 | struct sctp_ulpevent *ev; | |
853 | ||
854 | if (!sctp_vtag_verify(chunk, asoc)) | |
855 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
856 | ||
857 | /* Verify that the chunk length for the COOKIE-ACK is OK. | |
858 | * If we don't do this, any bundled chunks may be junked. | |
859 | */ | |
860 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
861 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
862 | commands); | |
863 | ||
864 | /* Reset init error count upon receipt of COOKIE-ACK, | |
865 | * to avoid problems with the managemement of this | |
866 | * counter in stale cookie situations when a transition back | |
867 | * from the COOKIE-ECHOED state to the COOKIE-WAIT | |
868 | * state is performed. | |
869 | */ | |
3f7a87d2 | 870 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); |
1da177e4 LT |
871 | |
872 | /* RFC 2960 5.1 Normal Establishment of an Association | |
873 | * | |
874 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move | |
875 | * from the COOKIE-ECHOED state to the ESTABLISHED state, | |
876 | * stopping the T1-cookie timer. | |
877 | */ | |
878 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
879 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
880 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
881 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
882 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
883 | SCTP_INC_STATS(SCTP_MIB_ACTIVEESTABS); | |
884 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
885 | if (asoc->autoclose) | |
886 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
887 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
1da177e4 LT |
888 | |
889 | /* It may also notify its ULP about the successful | |
890 | * establishment of the association with a Communication Up | |
891 | * notification (see Section 10). | |
892 | */ | |
893 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, | |
894 | 0, asoc->c.sinit_num_ostreams, | |
895 | asoc->c.sinit_max_instreams, | |
a5a35e76 | 896 | NULL, GFP_ATOMIC); |
1da177e4 LT |
897 | |
898 | if (!ev) | |
899 | goto nomem; | |
900 | ||
901 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
902 | ||
903 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 904 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 905 | * delivers this notification to inform the application that of the |
0f3fffd8 | 906 | * peers requested adaptation layer. |
1da177e4 | 907 | */ |
0f3fffd8 ISJ |
908 | if (asoc->peer.adaptation_ind) { |
909 | ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); | |
1da177e4 LT |
910 | if (!ev) |
911 | goto nomem; | |
912 | ||
913 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
914 | SCTP_ULPEVENT(ev)); | |
915 | } | |
916 | ||
917 | return SCTP_DISPOSITION_CONSUME; | |
918 | nomem: | |
919 | return SCTP_DISPOSITION_NOMEM; | |
920 | } | |
921 | ||
922 | /* Generate and sendout a heartbeat packet. */ | |
923 | static sctp_disposition_t sctp_sf_heartbeat(const struct sctp_endpoint *ep, | |
924 | const struct sctp_association *asoc, | |
925 | const sctp_subtype_t type, | |
926 | void *arg, | |
927 | sctp_cmd_seq_t *commands) | |
928 | { | |
929 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
930 | struct sctp_chunk *reply; | |
931 | sctp_sender_hb_info_t hbinfo; | |
932 | size_t paylen = 0; | |
933 | ||
934 | hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO; | |
935 | hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t)); | |
63de08f4 | 936 | hbinfo.daddr = transport->ipaddr; |
1da177e4 | 937 | hbinfo.sent_at = jiffies; |
ad8fec17 | 938 | hbinfo.hb_nonce = transport->hb_nonce; |
1da177e4 LT |
939 | |
940 | /* Send a heartbeat to our peer. */ | |
941 | paylen = sizeof(sctp_sender_hb_info_t); | |
942 | reply = sctp_make_heartbeat(asoc, transport, &hbinfo, paylen); | |
943 | if (!reply) | |
944 | return SCTP_DISPOSITION_NOMEM; | |
945 | ||
946 | /* Set rto_pending indicating that an RTT measurement | |
947 | * is started with this heartbeat chunk. | |
948 | */ | |
949 | sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING, | |
950 | SCTP_TRANSPORT(transport)); | |
951 | ||
952 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
953 | return SCTP_DISPOSITION_CONSUME; | |
954 | } | |
955 | ||
956 | /* Generate a HEARTBEAT packet on the given transport. */ | |
957 | sctp_disposition_t sctp_sf_sendbeat_8_3(const struct sctp_endpoint *ep, | |
958 | const struct sctp_association *asoc, | |
959 | const sctp_subtype_t type, | |
960 | void *arg, | |
961 | sctp_cmd_seq_t *commands) | |
962 | { | |
963 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
964 | ||
fd10279b | 965 | if (asoc->overall_error_count > asoc->max_retrans) { |
8de8c873 SS |
966 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
967 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
968 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
969 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 970 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
971 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
972 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
973 | return SCTP_DISPOSITION_DELETE_TCB; | |
974 | } | |
975 | ||
976 | /* Section 3.3.5. | |
977 | * The Sender-specific Heartbeat Info field should normally include | |
978 | * information about the sender's current time when this HEARTBEAT | |
979 | * chunk is sent and the destination transport address to which this | |
980 | * HEARTBEAT is sent (see Section 8.3). | |
981 | */ | |
982 | ||
52ccb8e9 | 983 | if (transport->param_flags & SPP_HB_ENABLE) { |
1da177e4 LT |
984 | if (SCTP_DISPOSITION_NOMEM == |
985 | sctp_sf_heartbeat(ep, asoc, type, arg, | |
986 | commands)) | |
987 | return SCTP_DISPOSITION_NOMEM; | |
988 | /* Set transport error counter and association error counter | |
989 | * when sending heartbeat. | |
990 | */ | |
991 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_RESET, | |
992 | SCTP_TRANSPORT(transport)); | |
993 | } | |
994 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE, | |
995 | SCTP_TRANSPORT(transport)); | |
996 | ||
d808ad9a | 997 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
998 | } |
999 | ||
1000 | /* | |
1001 | * Process an heartbeat request. | |
1002 | * | |
1003 | * Section: 8.3 Path Heartbeat | |
1004 | * The receiver of the HEARTBEAT should immediately respond with a | |
1005 | * HEARTBEAT ACK that contains the Heartbeat Information field copied | |
1006 | * from the received HEARTBEAT chunk. | |
1007 | * | |
1008 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1009 | * When receiving an SCTP packet, the endpoint MUST ensure that the | |
1010 | * value in the Verification Tag field of the received SCTP packet | |
1011 | * matches its own Tag. If the received Verification Tag value does not | |
1012 | * match the receiver's own tag value, the receiver shall silently | |
1013 | * discard the packet and shall not process it any further except for | |
1014 | * those cases listed in Section 8.5.1 below. | |
1015 | * | |
1016 | * Inputs | |
1017 | * (endpoint, asoc, chunk) | |
1018 | * | |
1019 | * Outputs | |
1020 | * (asoc, reply_msg, msg_up, timers, counters) | |
1021 | * | |
1022 | * The return value is the disposition of the chunk. | |
1023 | */ | |
1024 | sctp_disposition_t sctp_sf_beat_8_3(const struct sctp_endpoint *ep, | |
1025 | const struct sctp_association *asoc, | |
1026 | const sctp_subtype_t type, | |
1027 | void *arg, | |
1028 | sctp_cmd_seq_t *commands) | |
1029 | { | |
1030 | struct sctp_chunk *chunk = arg; | |
1031 | struct sctp_chunk *reply; | |
1032 | size_t paylen = 0; | |
1033 | ||
1034 | if (!sctp_vtag_verify(chunk, asoc)) | |
1035 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1036 | ||
1037 | /* Make sure that the HEARTBEAT chunk has a valid length. */ | |
1038 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
1039 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1040 | commands); | |
1041 | ||
1042 | /* 8.3 The receiver of the HEARTBEAT should immediately | |
1043 | * respond with a HEARTBEAT ACK that contains the Heartbeat | |
1044 | * Information field copied from the received HEARTBEAT chunk. | |
1045 | */ | |
1046 | chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data; | |
1047 | paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t); | |
62b08083 SS |
1048 | if (!pskb_pull(chunk->skb, paylen)) |
1049 | goto nomem; | |
1da177e4 LT |
1050 | |
1051 | reply = sctp_make_heartbeat_ack(asoc, chunk, | |
1052 | chunk->subh.hb_hdr, paylen); | |
1053 | if (!reply) | |
1054 | goto nomem; | |
1055 | ||
1056 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
1057 | return SCTP_DISPOSITION_CONSUME; | |
1058 | ||
1059 | nomem: | |
1060 | return SCTP_DISPOSITION_NOMEM; | |
1061 | } | |
1062 | ||
1063 | /* | |
1064 | * Process the returning HEARTBEAT ACK. | |
1065 | * | |
1066 | * Section: 8.3 Path Heartbeat | |
1067 | * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT | |
1068 | * should clear the error counter of the destination transport | |
1069 | * address to which the HEARTBEAT was sent, and mark the destination | |
1070 | * transport address as active if it is not so marked. The endpoint may | |
1071 | * optionally report to the upper layer when an inactive destination | |
1072 | * address is marked as active due to the reception of the latest | |
1073 | * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also | |
1074 | * clear the association overall error count as well (as defined | |
1075 | * in section 8.1). | |
1076 | * | |
1077 | * The receiver of the HEARTBEAT ACK should also perform an RTT | |
1078 | * measurement for that destination transport address using the time | |
1079 | * value carried in the HEARTBEAT ACK chunk. | |
1080 | * | |
1081 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1082 | * | |
1083 | * Inputs | |
1084 | * (endpoint, asoc, chunk) | |
1085 | * | |
1086 | * Outputs | |
1087 | * (asoc, reply_msg, msg_up, timers, counters) | |
1088 | * | |
1089 | * The return value is the disposition of the chunk. | |
1090 | */ | |
1091 | sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep, | |
1092 | const struct sctp_association *asoc, | |
1093 | const sctp_subtype_t type, | |
1094 | void *arg, | |
1095 | sctp_cmd_seq_t *commands) | |
1096 | { | |
1097 | struct sctp_chunk *chunk = arg; | |
1098 | union sctp_addr from_addr; | |
1099 | struct sctp_transport *link; | |
1100 | sctp_sender_hb_info_t *hbinfo; | |
1101 | unsigned long max_interval; | |
1102 | ||
1103 | if (!sctp_vtag_verify(chunk, asoc)) | |
1104 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1105 | ||
1106 | /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */ | |
1107 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
1108 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1109 | commands); | |
1110 | ||
1111 | hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; | |
a601266e VY |
1112 | /* Make sure that the length of the parameter is what we expect */ |
1113 | if (ntohs(hbinfo->param_hdr.length) != | |
1114 | sizeof(sctp_sender_hb_info_t)) { | |
1115 | return SCTP_DISPOSITION_DISCARD; | |
1116 | } | |
1117 | ||
1da177e4 | 1118 | from_addr = hbinfo->daddr; |
63de08f4 | 1119 | link = sctp_assoc_lookup_paddr(asoc, &from_addr); |
1da177e4 LT |
1120 | |
1121 | /* This should never happen, but lets log it if so. */ | |
3f7a87d2 FF |
1122 | if (unlikely(!link)) { |
1123 | if (from_addr.sa.sa_family == AF_INET6) { | |
d99fa429 WY |
1124 | if (net_ratelimit()) |
1125 | printk(KERN_WARNING | |
1126 | "%s association %p could not find address " | |
1127 | NIP6_FMT "\n", | |
0dc47877 | 1128 | __func__, |
d99fa429 WY |
1129 | asoc, |
1130 | NIP6(from_addr.v6.sin6_addr)); | |
3f7a87d2 | 1131 | } else { |
d99fa429 WY |
1132 | if (net_ratelimit()) |
1133 | printk(KERN_WARNING | |
1134 | "%s association %p could not find address " | |
1135 | NIPQUAD_FMT "\n", | |
0dc47877 | 1136 | __func__, |
d99fa429 WY |
1137 | asoc, |
1138 | NIPQUAD(from_addr.v4.sin_addr.s_addr)); | |
3f7a87d2 | 1139 | } |
1da177e4 LT |
1140 | return SCTP_DISPOSITION_DISCARD; |
1141 | } | |
1142 | ||
ad8fec17 SS |
1143 | /* Validate the 64-bit random nonce. */ |
1144 | if (hbinfo->hb_nonce != link->hb_nonce) | |
1145 | return SCTP_DISPOSITION_DISCARD; | |
1146 | ||
52ccb8e9 | 1147 | max_interval = link->hbinterval + link->rto; |
1da177e4 LT |
1148 | |
1149 | /* Check if the timestamp looks valid. */ | |
1150 | if (time_after(hbinfo->sent_at, jiffies) || | |
1151 | time_after(jiffies, hbinfo->sent_at + max_interval)) { | |
9ee46f1d | 1152 | SCTP_DEBUG_PRINTK("%s: HEARTBEAT ACK with invalid timestamp " |
1da177e4 | 1153 | "received for transport: %p\n", |
0dc47877 | 1154 | __func__, link); |
1da177e4 LT |
1155 | return SCTP_DISPOSITION_DISCARD; |
1156 | } | |
1157 | ||
1158 | /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of | |
1159 | * the HEARTBEAT should clear the error counter of the | |
1160 | * destination transport address to which the HEARTBEAT was | |
1161 | * sent and mark the destination transport address as active if | |
1162 | * it is not so marked. | |
1163 | */ | |
1164 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link)); | |
1165 | ||
1166 | return SCTP_DISPOSITION_CONSUME; | |
1167 | } | |
1168 | ||
1169 | /* Helper function to send out an abort for the restart | |
1170 | * condition. | |
1171 | */ | |
1172 | static int sctp_sf_send_restart_abort(union sctp_addr *ssa, | |
1173 | struct sctp_chunk *init, | |
1174 | sctp_cmd_seq_t *commands) | |
1175 | { | |
1176 | int len; | |
1177 | struct sctp_packet *pkt; | |
1178 | union sctp_addr_param *addrparm; | |
1179 | struct sctp_errhdr *errhdr; | |
1180 | struct sctp_endpoint *ep; | |
1181 | char buffer[sizeof(struct sctp_errhdr)+sizeof(union sctp_addr_param)]; | |
1182 | struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family); | |
1183 | ||
1184 | /* Build the error on the stack. We are way to malloc crazy | |
1185 | * throughout the code today. | |
1186 | */ | |
1187 | errhdr = (struct sctp_errhdr *)buffer; | |
1188 | addrparm = (union sctp_addr_param *)errhdr->variable; | |
1189 | ||
1190 | /* Copy into a parm format. */ | |
1191 | len = af->to_addr_param(ssa, addrparm); | |
1192 | len += sizeof(sctp_errhdr_t); | |
1193 | ||
1194 | errhdr->cause = SCTP_ERROR_RESTART; | |
1195 | errhdr->length = htons(len); | |
1196 | ||
1197 | /* Assign to the control socket. */ | |
1198 | ep = sctp_sk((sctp_get_ctl_sock()))->ep; | |
1199 | ||
1200 | /* Association is NULL since this may be a restart attack and we | |
1201 | * want to send back the attacker's vtag. | |
1202 | */ | |
1203 | pkt = sctp_abort_pkt_new(ep, NULL, init, errhdr, len); | |
1204 | ||
1205 | if (!pkt) | |
1206 | goto out; | |
1207 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt)); | |
1208 | ||
1209 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1210 | ||
1211 | /* Discard the rest of the inbound packet. */ | |
1212 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); | |
1213 | ||
1214 | out: | |
1215 | /* Even if there is no memory, treat as a failure so | |
1216 | * the packet will get dropped. | |
1217 | */ | |
1218 | return 0; | |
1219 | } | |
1220 | ||
1221 | /* A restart is occurring, check to make sure no new addresses | |
1222 | * are being added as we may be under a takeover attack. | |
1223 | */ | |
1224 | static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, | |
1225 | const struct sctp_association *asoc, | |
1226 | struct sctp_chunk *init, | |
1227 | sctp_cmd_seq_t *commands) | |
1228 | { | |
1229 | struct sctp_transport *new_addr, *addr; | |
1da177e4 LT |
1230 | int found; |
1231 | ||
1232 | /* Implementor's Guide - Sectin 5.2.2 | |
1233 | * ... | |
1234 | * Before responding the endpoint MUST check to see if the | |
1235 | * unexpected INIT adds new addresses to the association. If new | |
1236 | * addresses are added to the association, the endpoint MUST respond | |
1237 | * with an ABORT.. | |
1238 | */ | |
1239 | ||
1240 | /* Search through all current addresses and make sure | |
1241 | * we aren't adding any new ones. | |
1242 | */ | |
1243 | new_addr = NULL; | |
1244 | found = 0; | |
1245 | ||
9dbc15f0 RD |
1246 | list_for_each_entry(new_addr, &new_asoc->peer.transport_addr_list, |
1247 | transports) { | |
1da177e4 | 1248 | found = 0; |
9dbc15f0 RD |
1249 | list_for_each_entry(addr, &asoc->peer.transport_addr_list, |
1250 | transports) { | |
5f242a13 AV |
1251 | if (sctp_cmp_addr_exact(&new_addr->ipaddr, |
1252 | &addr->ipaddr)) { | |
1da177e4 LT |
1253 | found = 1; |
1254 | break; | |
1255 | } | |
1256 | } | |
1257 | if (!found) | |
1258 | break; | |
1259 | } | |
1260 | ||
1261 | /* If a new address was added, ABORT the sender. */ | |
1262 | if (!found && new_addr) { | |
7dd8a582 | 1263 | sctp_sf_send_restart_abort(&new_addr->ipaddr, init, commands); |
1da177e4 LT |
1264 | } |
1265 | ||
1266 | /* Return success if all addresses were found. */ | |
1267 | return found; | |
1268 | } | |
1269 | ||
1270 | /* Populate the verification/tie tags based on overlapping INIT | |
1271 | * scenario. | |
1272 | * | |
1273 | * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state. | |
1274 | */ | |
1275 | static void sctp_tietags_populate(struct sctp_association *new_asoc, | |
1276 | const struct sctp_association *asoc) | |
1277 | { | |
1278 | switch (asoc->state) { | |
1279 | ||
1280 | /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */ | |
1281 | ||
1282 | case SCTP_STATE_COOKIE_WAIT: | |
1283 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1284 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1285 | new_asoc->c.peer_ttag = 0; | |
1286 | break; | |
1287 | ||
1288 | case SCTP_STATE_COOKIE_ECHOED: | |
1289 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1290 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1291 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1292 | break; | |
1293 | ||
1294 | /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED, | |
1295 | * COOKIE-WAIT and SHUTDOWN-ACK-SENT | |
1296 | */ | |
1297 | default: | |
1298 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1299 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1300 | break; | |
3ff50b79 | 1301 | } |
1da177e4 LT |
1302 | |
1303 | /* Other parameters for the endpoint SHOULD be copied from the | |
1304 | * existing parameters of the association (e.g. number of | |
1305 | * outbound streams) into the INIT ACK and cookie. | |
1306 | */ | |
1307 | new_asoc->rwnd = asoc->rwnd; | |
1308 | new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams; | |
1309 | new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams; | |
1310 | new_asoc->c.initial_tsn = asoc->c.initial_tsn; | |
1311 | } | |
1312 | ||
1313 | /* | |
1314 | * Compare vtag/tietag values to determine unexpected COOKIE-ECHO | |
1315 | * handling action. | |
1316 | * | |
1317 | * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists. | |
1318 | * | |
1319 | * Returns value representing action to be taken. These action values | |
1320 | * correspond to Action/Description values in RFC 2960, Table 2. | |
1321 | */ | |
1322 | static char sctp_tietags_compare(struct sctp_association *new_asoc, | |
1323 | const struct sctp_association *asoc) | |
1324 | { | |
1325 | /* In this case, the peer may have restarted. */ | |
1326 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1327 | (asoc->c.peer_vtag != new_asoc->c.peer_vtag) && | |
1328 | (asoc->c.my_vtag == new_asoc->c.my_ttag) && | |
1329 | (asoc->c.peer_vtag == new_asoc->c.peer_ttag)) | |
1330 | return 'A'; | |
1331 | ||
1332 | /* Collision case B. */ | |
1333 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1334 | ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) || | |
1335 | (0 == asoc->c.peer_vtag))) { | |
1336 | return 'B'; | |
1337 | } | |
1338 | ||
1339 | /* Collision case D. */ | |
1340 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1341 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag)) | |
1342 | return 'D'; | |
1343 | ||
1344 | /* Collision case C. */ | |
1345 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1346 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag) && | |
1347 | (0 == new_asoc->c.my_ttag) && | |
1348 | (0 == new_asoc->c.peer_ttag)) | |
1349 | return 'C'; | |
1350 | ||
1351 | /* No match to any of the special cases; discard this packet. */ | |
1352 | return 'E'; | |
1353 | } | |
1354 | ||
1355 | /* Common helper routine for both duplicate and simulataneous INIT | |
1356 | * chunk handling. | |
1357 | */ | |
1358 | static sctp_disposition_t sctp_sf_do_unexpected_init( | |
1359 | const struct sctp_endpoint *ep, | |
1360 | const struct sctp_association *asoc, | |
1361 | const sctp_subtype_t type, | |
1362 | void *arg, sctp_cmd_seq_t *commands) | |
1363 | { | |
1364 | sctp_disposition_t retval; | |
1365 | struct sctp_chunk *chunk = arg; | |
1366 | struct sctp_chunk *repl; | |
1367 | struct sctp_association *new_asoc; | |
1368 | struct sctp_chunk *err_chunk; | |
1369 | struct sctp_packet *packet; | |
1370 | sctp_unrecognized_param_t *unk_param; | |
1371 | int len; | |
1372 | ||
1373 | /* 6.10 Bundling | |
1374 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
1375 | * SHUTDOWN COMPLETE with any other chunks. | |
1376 | * | |
1377 | * IG Section 2.11.2 | |
1378 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
1379 | * enforce these rules by silently discarding an arriving packet | |
1380 | * with an INIT chunk that is bundled with other chunks. | |
1381 | */ | |
1382 | if (!chunk->singleton) | |
1383 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1384 | ||
1385 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification | |
d808ad9a | 1386 | * Tag. |
1da177e4 LT |
1387 | */ |
1388 | if (chunk->sctp_hdr->vtag != 0) | |
1389 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
1390 | ||
1391 | /* Make sure that the INIT chunk has a valid length. | |
1392 | * In this case, we generate a protocol violation since we have | |
1393 | * an association established. | |
1394 | */ | |
1395 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
1396 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1397 | commands); | |
1398 | /* Grab the INIT header. */ | |
1399 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
1400 | ||
1401 | /* Tag the variable length parameters. */ | |
1402 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
1403 | ||
1404 | /* Verify the INIT chunk before processing it. */ | |
1405 | err_chunk = NULL; | |
1406 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
1407 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
1408 | &err_chunk)) { | |
1409 | /* This chunk contains fatal error. It is to be discarded. | |
1410 | * Send an ABORT, with causes if there is any. | |
1411 | */ | |
1412 | if (err_chunk) { | |
1413 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
1414 | (__u8 *)(err_chunk->chunk_hdr) + | |
1415 | sizeof(sctp_chunkhdr_t), | |
1416 | ntohs(err_chunk->chunk_hdr->length) - | |
1417 | sizeof(sctp_chunkhdr_t)); | |
1418 | ||
1419 | if (packet) { | |
1420 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
1421 | SCTP_PACKET(packet)); | |
1422 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1423 | retval = SCTP_DISPOSITION_CONSUME; | |
1424 | } else { | |
1425 | retval = SCTP_DISPOSITION_NOMEM; | |
1426 | } | |
1427 | goto cleanup; | |
1428 | } else { | |
1429 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
1430 | commands); | |
1431 | } | |
1432 | } | |
1433 | ||
1434 | /* | |
1435 | * Other parameters for the endpoint SHOULD be copied from the | |
1436 | * existing parameters of the association (e.g. number of | |
1437 | * outbound streams) into the INIT ACK and cookie. | |
1438 | * FIXME: We are copying parameters from the endpoint not the | |
1439 | * association. | |
1440 | */ | |
1441 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
1442 | if (!new_asoc) | |
1443 | goto nomem; | |
1444 | ||
1445 | /* In the outbound INIT ACK the endpoint MUST copy its current | |
1446 | * Verification Tag and Peers Verification tag into a reserved | |
1447 | * place (local tie-tag and per tie-tag) within the state cookie. | |
1448 | */ | |
1449 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1450 | sctp_source(chunk), | |
1451 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
df7deeb5 VY |
1452 | GFP_ATOMIC)) |
1453 | goto nomem; | |
1da177e4 LT |
1454 | |
1455 | /* Make sure no new addresses are being added during the | |
1456 | * restart. Do not do this check for COOKIE-WAIT state, | |
1457 | * since there are no peer addresses to check against. | |
1458 | * Upon return an ABORT will have been sent if needed. | |
1459 | */ | |
1460 | if (!sctp_state(asoc, COOKIE_WAIT)) { | |
1461 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, | |
1462 | commands)) { | |
1463 | retval = SCTP_DISPOSITION_CONSUME; | |
df7deeb5 | 1464 | goto nomem_retval; |
1da177e4 LT |
1465 | } |
1466 | } | |
1467 | ||
1468 | sctp_tietags_populate(new_asoc, asoc); | |
1469 | ||
1470 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ | |
1471 | ||
1472 | /* If there are errors need to be reported for unknown parameters, | |
1473 | * make sure to reserve enough room in the INIT ACK for them. | |
1474 | */ | |
1475 | len = 0; | |
1476 | if (err_chunk) { | |
1477 | len = ntohs(err_chunk->chunk_hdr->length) - | |
1478 | sizeof(sctp_chunkhdr_t); | |
1479 | } | |
1480 | ||
1481 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0) | |
1482 | goto nomem; | |
1483 | ||
1484 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); | |
1485 | if (!repl) | |
1486 | goto nomem; | |
1487 | ||
1488 | /* If there are errors need to be reported for unknown parameters, | |
1489 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
1490 | * parameter. | |
1491 | */ | |
1492 | if (err_chunk) { | |
1493 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
1494 | * ERROR chunk generated by sctp_verify_init(). Since the | |
1495 | * error cause code for "unknown parameter" and the | |
1496 | * "Unrecognized parameter" type is the same, we can | |
1497 | * construct the parameters in INIT ACK by copying the | |
1498 | * ERROR causes over. | |
1499 | */ | |
1500 | unk_param = (sctp_unrecognized_param_t *) | |
1501 | ((__u8 *)(err_chunk->chunk_hdr) + | |
1502 | sizeof(sctp_chunkhdr_t)); | |
1503 | /* Replace the cause code with the "Unrecognized parameter" | |
1504 | * parameter type. | |
1505 | */ | |
1506 | sctp_addto_chunk(repl, len, unk_param); | |
1507 | } | |
1508 | ||
1509 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1510 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1511 | ||
1512 | /* | |
1513 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
1514 | * "Z" MUST NOT allocate any resources for this new association. | |
1515 | * Otherwise, "Z" will be vulnerable to resource attacks. | |
1516 | */ | |
1517 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1518 | retval = SCTP_DISPOSITION_CONSUME; | |
1519 | ||
df7deeb5 VY |
1520 | return retval; |
1521 | ||
1522 | nomem: | |
1523 | retval = SCTP_DISPOSITION_NOMEM; | |
1524 | nomem_retval: | |
1525 | if (new_asoc) | |
1526 | sctp_association_free(new_asoc); | |
1da177e4 LT |
1527 | cleanup: |
1528 | if (err_chunk) | |
1529 | sctp_chunk_free(err_chunk); | |
1530 | return retval; | |
1da177e4 LT |
1531 | } |
1532 | ||
1533 | /* | |
1534 | * Handle simultanous INIT. | |
1535 | * This means we started an INIT and then we got an INIT request from | |
1536 | * our peer. | |
1537 | * | |
1538 | * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B) | |
1539 | * This usually indicates an initialization collision, i.e., each | |
1540 | * endpoint is attempting, at about the same time, to establish an | |
1541 | * association with the other endpoint. | |
1542 | * | |
1543 | * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an | |
1544 | * endpoint MUST respond with an INIT ACK using the same parameters it | |
1545 | * sent in its original INIT chunk (including its Verification Tag, | |
1546 | * unchanged). These original parameters are combined with those from the | |
1547 | * newly received INIT chunk. The endpoint shall also generate a State | |
1548 | * Cookie with the INIT ACK. The endpoint uses the parameters sent in its | |
1549 | * INIT to calculate the State Cookie. | |
1550 | * | |
1551 | * After that, the endpoint MUST NOT change its state, the T1-init | |
1552 | * timer shall be left running and the corresponding TCB MUST NOT be | |
1553 | * destroyed. The normal procedures for handling State Cookies when | |
1554 | * a TCB exists will resolve the duplicate INITs to a single association. | |
1555 | * | |
1556 | * For an endpoint that is in the COOKIE-ECHOED state it MUST populate | |
1557 | * its Tie-Tags with the Tag information of itself and its peer (see | |
1558 | * section 5.2.2 for a description of the Tie-Tags). | |
1559 | * | |
1560 | * Verification Tag: Not explicit, but an INIT can not have a valid | |
1561 | * verification tag, so we skip the check. | |
1562 | * | |
1563 | * Inputs | |
1564 | * (endpoint, asoc, chunk) | |
1565 | * | |
1566 | * Outputs | |
1567 | * (asoc, reply_msg, msg_up, timers, counters) | |
1568 | * | |
1569 | * The return value is the disposition of the chunk. | |
1570 | */ | |
1571 | sctp_disposition_t sctp_sf_do_5_2_1_siminit(const struct sctp_endpoint *ep, | |
1572 | const struct sctp_association *asoc, | |
1573 | const sctp_subtype_t type, | |
1574 | void *arg, | |
1575 | sctp_cmd_seq_t *commands) | |
1576 | { | |
1577 | /* Call helper to do the real work for both simulataneous and | |
1578 | * duplicate INIT chunk handling. | |
1579 | */ | |
1580 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1581 | } | |
1582 | ||
1583 | /* | |
1584 | * Handle duplicated INIT messages. These are usually delayed | |
1585 | * restransmissions. | |
1586 | * | |
1587 | * Section: 5.2.2 Unexpected INIT in States Other than CLOSED, | |
1588 | * COOKIE-ECHOED and COOKIE-WAIT | |
1589 | * | |
1590 | * Unless otherwise stated, upon reception of an unexpected INIT for | |
1591 | * this association, the endpoint shall generate an INIT ACK with a | |
1592 | * State Cookie. In the outbound INIT ACK the endpoint MUST copy its | |
1593 | * current Verification Tag and peer's Verification Tag into a reserved | |
1594 | * place within the state cookie. We shall refer to these locations as | |
1595 | * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet | |
1596 | * containing this INIT ACK MUST carry a Verification Tag value equal to | |
1597 | * the Initiation Tag found in the unexpected INIT. And the INIT ACK | |
1598 | * MUST contain a new Initiation Tag (randomly generated see Section | |
1599 | * 5.3.1). Other parameters for the endpoint SHOULD be copied from the | |
1600 | * existing parameters of the association (e.g. number of outbound | |
1601 | * streams) into the INIT ACK and cookie. | |
1602 | * | |
1603 | * After sending out the INIT ACK, the endpoint shall take no further | |
1604 | * actions, i.e., the existing association, including its current state, | |
1605 | * and the corresponding TCB MUST NOT be changed. | |
1606 | * | |
1607 | * Note: Only when a TCB exists and the association is not in a COOKIE- | |
1608 | * WAIT state are the Tie-Tags populated. For a normal association INIT | |
1609 | * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be | |
1610 | * set to 0 (indicating that no previous TCB existed). The INIT ACK and | |
1611 | * State Cookie are populated as specified in section 5.2.1. | |
1612 | * | |
1613 | * Verification Tag: Not specified, but an INIT has no way of knowing | |
1614 | * what the verification tag could be, so we ignore it. | |
1615 | * | |
1616 | * Inputs | |
1617 | * (endpoint, asoc, chunk) | |
1618 | * | |
1619 | * Outputs | |
1620 | * (asoc, reply_msg, msg_up, timers, counters) | |
1621 | * | |
1622 | * The return value is the disposition of the chunk. | |
1623 | */ | |
1624 | sctp_disposition_t sctp_sf_do_5_2_2_dupinit(const struct sctp_endpoint *ep, | |
1625 | const struct sctp_association *asoc, | |
1626 | const sctp_subtype_t type, | |
1627 | void *arg, | |
1628 | sctp_cmd_seq_t *commands) | |
1629 | { | |
1630 | /* Call helper to do the real work for both simulataneous and | |
1631 | * duplicate INIT chunk handling. | |
1632 | */ | |
1633 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1634 | } | |
1635 | ||
1636 | ||
610ab73a VY |
1637 | /* |
1638 | * Unexpected INIT-ACK handler. | |
1639 | * | |
1640 | * Section 5.2.3 | |
1641 | * If an INIT ACK received by an endpoint in any state other than the | |
1642 | * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk. | |
1643 | * An unexpected INIT ACK usually indicates the processing of an old or | |
1644 | * duplicated INIT chunk. | |
1645 | */ | |
1646 | sctp_disposition_t sctp_sf_do_5_2_3_initack(const struct sctp_endpoint *ep, | |
1647 | const struct sctp_association *asoc, | |
1648 | const sctp_subtype_t type, | |
1649 | void *arg, sctp_cmd_seq_t *commands) | |
1650 | { | |
1651 | /* Per the above section, we'll discard the chunk if we have an | |
1652 | * endpoint. If this is an OOTB INIT-ACK, treat it as such. | |
1653 | */ | |
d808ad9a | 1654 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) |
610ab73a VY |
1655 | return sctp_sf_ootb(ep, asoc, type, arg, commands); |
1656 | else | |
1657 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
1658 | } | |
1da177e4 LT |
1659 | |
1660 | /* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A') | |
1661 | * | |
1662 | * Section 5.2.4 | |
1663 | * A) In this case, the peer may have restarted. | |
1664 | */ | |
1665 | static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep, | |
1666 | const struct sctp_association *asoc, | |
1667 | struct sctp_chunk *chunk, | |
1668 | sctp_cmd_seq_t *commands, | |
1669 | struct sctp_association *new_asoc) | |
1670 | { | |
1671 | sctp_init_chunk_t *peer_init; | |
1672 | struct sctp_ulpevent *ev; | |
1673 | struct sctp_chunk *repl; | |
1674 | struct sctp_chunk *err; | |
1675 | sctp_disposition_t disposition; | |
1676 | ||
1677 | /* new_asoc is a brand-new association, so these are not yet | |
1678 | * side effects--it is safe to run them here. | |
1679 | */ | |
1680 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1681 | ||
1682 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1683 | sctp_source(chunk), peer_init, | |
1684 | GFP_ATOMIC)) | |
1685 | goto nomem; | |
1686 | ||
1687 | /* Make sure no new addresses are being added during the | |
1688 | * restart. Though this is a pretty complicated attack | |
1689 | * since you'd have to get inside the cookie. | |
1690 | */ | |
1691 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) { | |
1692 | return SCTP_DISPOSITION_CONSUME; | |
1693 | } | |
1694 | ||
1695 | /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes | |
1696 | * the peer has restarted (Action A), it MUST NOT setup a new | |
1697 | * association but instead resend the SHUTDOWN ACK and send an ERROR | |
1698 | * chunk with a "Cookie Received while Shutting Down" error cause to | |
1699 | * its peer. | |
1700 | */ | |
1701 | if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) { | |
1702 | disposition = sctp_sf_do_9_2_reshutack(ep, asoc, | |
1703 | SCTP_ST_CHUNK(chunk->chunk_hdr->type), | |
1704 | chunk, commands); | |
1705 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
1706 | goto nomem; | |
1707 | ||
1708 | err = sctp_make_op_error(asoc, chunk, | |
1709 | SCTP_ERROR_COOKIE_IN_SHUTDOWN, | |
1710 | NULL, 0); | |
1711 | if (err) | |
1712 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1713 | SCTP_CHUNK(err)); | |
1714 | ||
1715 | return SCTP_DISPOSITION_CONSUME; | |
1716 | } | |
1717 | ||
1718 | /* For now, fail any unsent/unacked data. Consider the optional | |
1719 | * choice of resending of this data. | |
1720 | */ | |
1721 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL()); | |
1722 | ||
1da177e4 LT |
1723 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
1724 | if (!repl) | |
1725 | goto nomem; | |
1726 | ||
1da177e4 LT |
1727 | /* Report association restart to upper layer. */ |
1728 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0, | |
1729 | new_asoc->c.sinit_num_ostreams, | |
1730 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 1731 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1732 | if (!ev) |
1733 | goto nomem_ev; | |
1734 | ||
df7deeb5 VY |
1735 | /* Update the content of current association. */ |
1736 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1737 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1738 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
1739 | return SCTP_DISPOSITION_CONSUME; | |
1740 | ||
1741 | nomem_ev: | |
1742 | sctp_chunk_free(repl); | |
1743 | nomem: | |
1744 | return SCTP_DISPOSITION_NOMEM; | |
1745 | } | |
1746 | ||
1747 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B') | |
1748 | * | |
1749 | * Section 5.2.4 | |
1750 | * B) In this case, both sides may be attempting to start an association | |
1751 | * at about the same time but the peer endpoint started its INIT | |
1752 | * after responding to the local endpoint's INIT | |
1753 | */ | |
1754 | /* This case represents an initialization collision. */ | |
1755 | static sctp_disposition_t sctp_sf_do_dupcook_b(const struct sctp_endpoint *ep, | |
1756 | const struct sctp_association *asoc, | |
1757 | struct sctp_chunk *chunk, | |
1758 | sctp_cmd_seq_t *commands, | |
1759 | struct sctp_association *new_asoc) | |
1760 | { | |
1761 | sctp_init_chunk_t *peer_init; | |
1da177e4 LT |
1762 | struct sctp_chunk *repl; |
1763 | ||
1764 | /* new_asoc is a brand-new association, so these are not yet | |
1765 | * side effects--it is safe to run them here. | |
1766 | */ | |
1767 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1768 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1769 | sctp_source(chunk), peer_init, | |
1770 | GFP_ATOMIC)) | |
1771 | goto nomem; | |
1772 | ||
1773 | /* Update the content of current association. */ | |
1774 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1775 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1776 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1777 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1778 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
1779 | ||
1780 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1781 | if (!repl) | |
1782 | goto nomem; | |
1783 | ||
1784 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1785 | |
1786 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1787 | * | |
1788 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
1789 | * send the Communication Up notification to the SCTP user | |
1790 | * upon reception of a valid COOKIE ECHO chunk. | |
07d93967 VY |
1791 | * |
1792 | * Sadly, this needs to be implemented as a side-effect, because | |
1793 | * we are not guaranteed to have set the association id of the real | |
1794 | * association and so these notifications need to be delayed until | |
1795 | * the association id is allocated. | |
1da177e4 | 1796 | */ |
1da177e4 | 1797 | |
07d93967 | 1798 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP)); |
1da177e4 LT |
1799 | |
1800 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1801 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 1802 | * delivers this notification to inform the application that of the |
0f3fffd8 | 1803 | * peers requested adaptation layer. |
07d93967 VY |
1804 | * |
1805 | * This also needs to be done as a side effect for the same reason as | |
1806 | * above. | |
1da177e4 | 1807 | */ |
07d93967 VY |
1808 | if (asoc->peer.adaptation_ind) |
1809 | sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL()); | |
1da177e4 LT |
1810 | |
1811 | return SCTP_DISPOSITION_CONSUME; | |
1812 | ||
1da177e4 LT |
1813 | nomem: |
1814 | return SCTP_DISPOSITION_NOMEM; | |
1815 | } | |
1816 | ||
1817 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C') | |
1818 | * | |
1819 | * Section 5.2.4 | |
1820 | * C) In this case, the local endpoint's cookie has arrived late. | |
1821 | * Before it arrived, the local endpoint sent an INIT and received an | |
1822 | * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag | |
1823 | * but a new tag of its own. | |
1824 | */ | |
1825 | /* This case represents an initialization collision. */ | |
1826 | static sctp_disposition_t sctp_sf_do_dupcook_c(const struct sctp_endpoint *ep, | |
1827 | const struct sctp_association *asoc, | |
1828 | struct sctp_chunk *chunk, | |
1829 | sctp_cmd_seq_t *commands, | |
1830 | struct sctp_association *new_asoc) | |
1831 | { | |
1832 | /* The cookie should be silently discarded. | |
1833 | * The endpoint SHOULD NOT change states and should leave | |
1834 | * any timers running. | |
1835 | */ | |
1836 | return SCTP_DISPOSITION_DISCARD; | |
1837 | } | |
1838 | ||
1839 | /* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D') | |
1840 | * | |
1841 | * Section 5.2.4 | |
1842 | * | |
1843 | * D) When both local and remote tags match the endpoint should always | |
1844 | * enter the ESTABLISHED state, if it has not already done so. | |
1845 | */ | |
1846 | /* This case represents an initialization collision. */ | |
1847 | static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep, | |
1848 | const struct sctp_association *asoc, | |
1849 | struct sctp_chunk *chunk, | |
1850 | sctp_cmd_seq_t *commands, | |
1851 | struct sctp_association *new_asoc) | |
1852 | { | |
df7deeb5 | 1853 | struct sctp_ulpevent *ev = NULL, *ai_ev = NULL; |
1da177e4 LT |
1854 | struct sctp_chunk *repl; |
1855 | ||
1856 | /* Clarification from Implementor's Guide: | |
1857 | * D) When both local and remote tags match the endpoint should | |
d808ad9a YH |
1858 | * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state. |
1859 | * It should stop any cookie timer that may be running and send | |
1860 | * a COOKIE ACK. | |
1da177e4 LT |
1861 | */ |
1862 | ||
1863 | /* Don't accidentally move back into established state. */ | |
1864 | if (asoc->state < SCTP_STATE_ESTABLISHED) { | |
1865 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1866 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
1867 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1868 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1869 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1870 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, | |
1871 | SCTP_NULL()); | |
1872 | ||
1873 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1874 | * | |
1875 | * D) IMPLEMENTATION NOTE: An implementation may choose | |
1876 | * to send the Communication Up notification to the | |
1877 | * SCTP user upon reception of a valid COOKIE | |
1878 | * ECHO chunk. | |
1879 | */ | |
df7deeb5 | 1880 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, |
1da177e4 | 1881 | SCTP_COMM_UP, 0, |
df7deeb5 VY |
1882 | asoc->c.sinit_num_ostreams, |
1883 | asoc->c.sinit_max_instreams, | |
9cbcbf4e | 1884 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1885 | if (!ev) |
1886 | goto nomem; | |
1da177e4 LT |
1887 | |
1888 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1889 | * When a peer sends a Adaptation Layer Indication parameter, |
1da177e4 | 1890 | * SCTP delivers this notification to inform the application |
0f3fffd8 | 1891 | * that of the peers requested adaptation layer. |
1da177e4 | 1892 | */ |
0f3fffd8 ISJ |
1893 | if (asoc->peer.adaptation_ind) { |
1894 | ai_ev = sctp_ulpevent_make_adaptation_indication(asoc, | |
1da177e4 | 1895 | GFP_ATOMIC); |
df7deeb5 | 1896 | if (!ai_ev) |
1da177e4 LT |
1897 | goto nomem; |
1898 | ||
1da177e4 LT |
1899 | } |
1900 | } | |
1da177e4 LT |
1901 | |
1902 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1903 | if (!repl) | |
1904 | goto nomem; | |
1905 | ||
2e3216cd VY |
1906 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
1907 | ||
df7deeb5 VY |
1908 | if (ev) |
1909 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1910 | SCTP_ULPEVENT(ev)); | |
1911 | if (ai_ev) | |
1912 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1913 | SCTP_ULPEVENT(ai_ev)); | |
1914 | ||
1da177e4 LT |
1915 | return SCTP_DISPOSITION_CONSUME; |
1916 | ||
1917 | nomem: | |
df7deeb5 VY |
1918 | if (ai_ev) |
1919 | sctp_ulpevent_free(ai_ev); | |
1da177e4 LT |
1920 | if (ev) |
1921 | sctp_ulpevent_free(ev); | |
1922 | return SCTP_DISPOSITION_NOMEM; | |
1923 | } | |
1924 | ||
1925 | /* | |
1926 | * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying | |
1927 | * chunk was retransmitted and then delayed in the network. | |
1928 | * | |
1929 | * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists | |
1930 | * | |
1931 | * Verification Tag: None. Do cookie validation. | |
1932 | * | |
1933 | * Inputs | |
1934 | * (endpoint, asoc, chunk) | |
1935 | * | |
1936 | * Outputs | |
1937 | * (asoc, reply_msg, msg_up, timers, counters) | |
1938 | * | |
1939 | * The return value is the disposition of the chunk. | |
1940 | */ | |
1941 | sctp_disposition_t sctp_sf_do_5_2_4_dupcook(const struct sctp_endpoint *ep, | |
1942 | const struct sctp_association *asoc, | |
1943 | const sctp_subtype_t type, | |
1944 | void *arg, | |
1945 | sctp_cmd_seq_t *commands) | |
1946 | { | |
1947 | sctp_disposition_t retval; | |
1948 | struct sctp_chunk *chunk = arg; | |
1949 | struct sctp_association *new_asoc; | |
1950 | int error = 0; | |
1951 | char action; | |
1952 | struct sctp_chunk *err_chk_p; | |
1953 | ||
1954 | /* Make sure that the chunk has a valid length from the protocol | |
1955 | * perspective. In this case check to make sure we have at least | |
1956 | * enough for the chunk header. Cookie length verification is | |
1957 | * done later. | |
1958 | */ | |
1959 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
1960 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1961 | commands); | |
1962 | ||
1963 | /* "Decode" the chunk. We have no optional parameters so we | |
1964 | * are in good shape. | |
1965 | */ | |
d808ad9a | 1966 | chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
1967 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
1968 | sizeof(sctp_chunkhdr_t))) | |
1969 | goto nomem; | |
1da177e4 LT |
1970 | |
1971 | /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie | |
1972 | * of a duplicate COOKIE ECHO match the Verification Tags of the | |
1973 | * current association, consider the State Cookie valid even if | |
1974 | * the lifespan is exceeded. | |
1975 | */ | |
1976 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
1977 | &err_chk_p); | |
1978 | ||
1979 | /* FIXME: | |
1980 | * If the re-build failed, what is the proper error path | |
1981 | * from here? | |
1982 | * | |
1983 | * [We should abort the association. --piggy] | |
1984 | */ | |
1985 | if (!new_asoc) { | |
1986 | /* FIXME: Several errors are possible. A bad cookie should | |
1987 | * be silently discarded, but think about logging it too. | |
1988 | */ | |
1989 | switch (error) { | |
1990 | case -SCTP_IERROR_NOMEM: | |
1991 | goto nomem; | |
1992 | ||
1993 | case -SCTP_IERROR_STALE_COOKIE: | |
1994 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
1995 | err_chk_p); | |
1996 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1997 | case -SCTP_IERROR_BAD_SIG: | |
1998 | default: | |
1999 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 2000 | } |
1da177e4 LT |
2001 | } |
2002 | ||
2003 | /* Compare the tie_tag in cookie with the verification tag of | |
2004 | * current association. | |
2005 | */ | |
2006 | action = sctp_tietags_compare(new_asoc, asoc); | |
2007 | ||
2008 | switch (action) { | |
2009 | case 'A': /* Association restart. */ | |
2010 | retval = sctp_sf_do_dupcook_a(ep, asoc, chunk, commands, | |
2011 | new_asoc); | |
2012 | break; | |
2013 | ||
2014 | case 'B': /* Collision case B. */ | |
2015 | retval = sctp_sf_do_dupcook_b(ep, asoc, chunk, commands, | |
2016 | new_asoc); | |
2017 | break; | |
2018 | ||
2019 | case 'C': /* Collision case C. */ | |
2020 | retval = sctp_sf_do_dupcook_c(ep, asoc, chunk, commands, | |
2021 | new_asoc); | |
2022 | break; | |
2023 | ||
2024 | case 'D': /* Collision case D. */ | |
2025 | retval = sctp_sf_do_dupcook_d(ep, asoc, chunk, commands, | |
2026 | new_asoc); | |
2027 | break; | |
2028 | ||
2029 | default: /* Discard packet for all others. */ | |
2030 | retval = sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2031 | break; | |
3ff50b79 | 2032 | } |
1da177e4 LT |
2033 | |
2034 | /* Delete the tempory new association. */ | |
2035 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
2036 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
2037 | ||
2038 | return retval; | |
2039 | ||
2040 | nomem: | |
2041 | return SCTP_DISPOSITION_NOMEM; | |
2042 | } | |
2043 | ||
2044 | /* | |
2045 | * Process an ABORT. (SHUTDOWN-PENDING state) | |
2046 | * | |
2047 | * See sctp_sf_do_9_1_abort(). | |
2048 | */ | |
2049 | sctp_disposition_t sctp_sf_shutdown_pending_abort( | |
2050 | const struct sctp_endpoint *ep, | |
2051 | const struct sctp_association *asoc, | |
2052 | const sctp_subtype_t type, | |
2053 | void *arg, | |
2054 | sctp_cmd_seq_t *commands) | |
2055 | { | |
2056 | struct sctp_chunk *chunk = arg; | |
2057 | ||
2058 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2059 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2060 | ||
2061 | /* Make sure that the ABORT chunk has a valid length. | |
2062 | * Since this is an ABORT chunk, we have to discard it | |
2063 | * because of the following text: | |
2064 | * RFC 2960, Section 3.3.7 | |
2065 | * If an endpoint receives an ABORT with a format error or for an | |
2066 | * association that doesn't exist, it MUST silently discard it. | |
2067 | * Becasue the length is "invalid", we can't really discard just | |
2068 | * as we do not know its true length. So, to be safe, discard the | |
2069 | * packet. | |
2070 | */ | |
2071 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2072 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2073 | ||
75205f47 VY |
2074 | /* ADD-IP: Special case for ABORT chunks |
2075 | * F4) One special consideration is that ABORT Chunks arriving | |
2076 | * destined to the IP address being deleted MUST be | |
2077 | * ignored (see Section 5.3.1 for further details). | |
2078 | */ | |
2079 | if (SCTP_ADDR_DEL == | |
2080 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2081 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2082 | ||
75205f47 | 2083 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); |
1da177e4 LT |
2084 | } |
2085 | ||
2086 | /* | |
2087 | * Process an ABORT. (SHUTDOWN-SENT state) | |
2088 | * | |
2089 | * See sctp_sf_do_9_1_abort(). | |
2090 | */ | |
2091 | sctp_disposition_t sctp_sf_shutdown_sent_abort(const struct sctp_endpoint *ep, | |
2092 | const struct sctp_association *asoc, | |
2093 | const sctp_subtype_t type, | |
2094 | void *arg, | |
2095 | sctp_cmd_seq_t *commands) | |
2096 | { | |
2097 | struct sctp_chunk *chunk = arg; | |
2098 | ||
2099 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2100 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2101 | ||
2102 | /* Make sure that the ABORT chunk has a valid length. | |
2103 | * Since this is an ABORT chunk, we have to discard it | |
2104 | * because of the following text: | |
2105 | * RFC 2960, Section 3.3.7 | |
2106 | * If an endpoint receives an ABORT with a format error or for an | |
2107 | * association that doesn't exist, it MUST silently discard it. | |
2108 | * Becasue the length is "invalid", we can't really discard just | |
2109 | * as we do not know its true length. So, to be safe, discard the | |
2110 | * packet. | |
2111 | */ | |
2112 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2113 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2114 | ||
75205f47 VY |
2115 | /* ADD-IP: Special case for ABORT chunks |
2116 | * F4) One special consideration is that ABORT Chunks arriving | |
2117 | * destined to the IP address being deleted MUST be | |
2118 | * ignored (see Section 5.3.1 for further details). | |
2119 | */ | |
2120 | if (SCTP_ADDR_DEL == | |
2121 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2122 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2123 | ||
1da177e4 LT |
2124 | /* Stop the T2-shutdown timer. */ |
2125 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2126 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2127 | ||
2128 | /* Stop the T5-shutdown guard timer. */ | |
2129 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2130 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2131 | ||
75205f47 | 2132 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); |
1da177e4 LT |
2133 | } |
2134 | ||
2135 | /* | |
2136 | * Process an ABORT. (SHUTDOWN-ACK-SENT state) | |
2137 | * | |
2138 | * See sctp_sf_do_9_1_abort(). | |
2139 | */ | |
2140 | sctp_disposition_t sctp_sf_shutdown_ack_sent_abort( | |
2141 | const struct sctp_endpoint *ep, | |
2142 | const struct sctp_association *asoc, | |
2143 | const sctp_subtype_t type, | |
2144 | void *arg, | |
2145 | sctp_cmd_seq_t *commands) | |
2146 | { | |
2147 | /* The same T2 timer, so we should be able to use | |
2148 | * common function with the SHUTDOWN-SENT state. | |
2149 | */ | |
2150 | return sctp_sf_shutdown_sent_abort(ep, asoc, type, arg, commands); | |
2151 | } | |
2152 | ||
2153 | /* | |
2154 | * Handle an Error received in COOKIE_ECHOED state. | |
2155 | * | |
2156 | * Only handle the error type of stale COOKIE Error, the other errors will | |
2157 | * be ignored. | |
2158 | * | |
2159 | * Inputs | |
2160 | * (endpoint, asoc, chunk) | |
2161 | * | |
2162 | * Outputs | |
2163 | * (asoc, reply_msg, msg_up, timers, counters) | |
2164 | * | |
2165 | * The return value is the disposition of the chunk. | |
2166 | */ | |
2167 | sctp_disposition_t sctp_sf_cookie_echoed_err(const struct sctp_endpoint *ep, | |
2168 | const struct sctp_association *asoc, | |
2169 | const sctp_subtype_t type, | |
2170 | void *arg, | |
2171 | sctp_cmd_seq_t *commands) | |
2172 | { | |
2173 | struct sctp_chunk *chunk = arg; | |
2174 | sctp_errhdr_t *err; | |
2175 | ||
2176 | if (!sctp_vtag_verify(chunk, asoc)) | |
2177 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2178 | ||
2179 | /* Make sure that the ERROR chunk has a valid length. | |
2180 | * The parameter walking depends on this as well. | |
2181 | */ | |
2182 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
2183 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2184 | commands); | |
2185 | ||
2186 | /* Process the error here */ | |
2187 | /* FUTURE FIXME: When PR-SCTP related and other optional | |
2188 | * parms are emitted, this will have to change to handle multiple | |
2189 | * errors. | |
2190 | */ | |
2191 | sctp_walk_errors(err, chunk->chunk_hdr) { | |
2192 | if (SCTP_ERROR_STALE_COOKIE == err->cause) | |
d808ad9a | 2193 | return sctp_sf_do_5_2_6_stale(ep, asoc, type, |
1da177e4 LT |
2194 | arg, commands); |
2195 | } | |
2196 | ||
2197 | /* It is possible to have malformed error causes, and that | |
2198 | * will cause us to end the walk early. However, since | |
2199 | * we are discarding the packet, there should be no adverse | |
2200 | * affects. | |
2201 | */ | |
2202 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2203 | } | |
2204 | ||
2205 | /* | |
2206 | * Handle a Stale COOKIE Error | |
2207 | * | |
2208 | * Section: 5.2.6 Handle Stale COOKIE Error | |
2209 | * If the association is in the COOKIE-ECHOED state, the endpoint may elect | |
2210 | * one of the following three alternatives. | |
2211 | * ... | |
2212 | * 3) Send a new INIT chunk to the endpoint, adding a Cookie | |
2213 | * Preservative parameter requesting an extension to the lifetime of | |
2214 | * the State Cookie. When calculating the time extension, an | |
2215 | * implementation SHOULD use the RTT information measured based on the | |
2216 | * previous COOKIE ECHO / ERROR exchange, and should add no more | |
2217 | * than 1 second beyond the measured RTT, due to long State Cookie | |
2218 | * lifetimes making the endpoint more subject to a replay attack. | |
2219 | * | |
2220 | * Verification Tag: Not explicit, but safe to ignore. | |
2221 | * | |
2222 | * Inputs | |
2223 | * (endpoint, asoc, chunk) | |
2224 | * | |
2225 | * Outputs | |
2226 | * (asoc, reply_msg, msg_up, timers, counters) | |
2227 | * | |
2228 | * The return value is the disposition of the chunk. | |
2229 | */ | |
2230 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, | |
2231 | const struct sctp_association *asoc, | |
2232 | const sctp_subtype_t type, | |
2233 | void *arg, | |
2234 | sctp_cmd_seq_t *commands) | |
2235 | { | |
2236 | struct sctp_chunk *chunk = arg; | |
2237 | time_t stale; | |
2238 | sctp_cookie_preserve_param_t bht; | |
2239 | sctp_errhdr_t *err; | |
2240 | struct sctp_chunk *reply; | |
2241 | struct sctp_bind_addr *bp; | |
3f7a87d2 | 2242 | int attempts = asoc->init_err_counter + 1; |
1da177e4 | 2243 | |
81845c21 | 2244 | if (attempts > asoc->max_init_attempts) { |
8de8c873 SS |
2245 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
2246 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 2247 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 2248 | SCTP_PERR(SCTP_ERROR_STALE_COOKIE)); |
1da177e4 LT |
2249 | return SCTP_DISPOSITION_DELETE_TCB; |
2250 | } | |
2251 | ||
2252 | err = (sctp_errhdr_t *)(chunk->skb->data); | |
2253 | ||
2254 | /* When calculating the time extension, an implementation | |
2255 | * SHOULD use the RTT information measured based on the | |
2256 | * previous COOKIE ECHO / ERROR exchange, and should add no | |
2257 | * more than 1 second beyond the measured RTT, due to long | |
2258 | * State Cookie lifetimes making the endpoint more subject to | |
2259 | * a replay attack. | |
2260 | * Measure of Staleness's unit is usec. (1/1000000 sec) | |
2261 | * Suggested Cookie Life-span Increment's unit is msec. | |
2262 | * (1/1000 sec) | |
2263 | * In general, if you use the suggested cookie life, the value | |
2264 | * found in the field of measure of staleness should be doubled | |
2265 | * to give ample time to retransmit the new cookie and thus | |
2266 | * yield a higher probability of success on the reattempt. | |
2267 | */ | |
34bcca28 | 2268 | stale = ntohl(*(__be32 *)((u8 *)err + sizeof(sctp_errhdr_t))); |
1da177e4 LT |
2269 | stale = (stale * 2) / 1000; |
2270 | ||
2271 | bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE; | |
2272 | bht.param_hdr.length = htons(sizeof(bht)); | |
2273 | bht.lifespan_increment = htonl(stale); | |
2274 | ||
2275 | /* Build that new INIT chunk. */ | |
2276 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; | |
2277 | reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht)); | |
2278 | if (!reply) | |
2279 | goto nomem; | |
2280 | ||
2281 | sctp_addto_chunk(reply, sizeof(bht), &bht); | |
2282 | ||
2283 | /* Clear peer's init_tag cached in assoc as we are sending a new INIT */ | |
2284 | sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL()); | |
2285 | ||
2286 | /* Stop pending T3-rtx and heartbeat timers */ | |
2287 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); | |
2288 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
2289 | ||
2290 | /* Delete non-primary peer ip addresses since we are transitioning | |
2291 | * back to the COOKIE-WAIT state | |
2292 | */ | |
2293 | sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL()); | |
2294 | ||
d808ad9a YH |
2295 | /* If we've sent any data bundled with COOKIE-ECHO we will need to |
2296 | * resend | |
1da177e4 | 2297 | */ |
b6157d8e | 2298 | sctp_add_cmd_sf(commands, SCTP_CMD_T1_RETRAN, |
1da177e4 LT |
2299 | SCTP_TRANSPORT(asoc->peer.primary_path)); |
2300 | ||
2301 | /* Cast away the const modifier, as we want to just | |
2302 | * rerun it through as a sideffect. | |
2303 | */ | |
3f7a87d2 | 2304 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL()); |
1da177e4 LT |
2305 | |
2306 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2307 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2308 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2309 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
2310 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
2311 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
2312 | ||
2313 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2314 | ||
2315 | return SCTP_DISPOSITION_CONSUME; | |
2316 | ||
2317 | nomem: | |
2318 | return SCTP_DISPOSITION_NOMEM; | |
2319 | } | |
2320 | ||
2321 | /* | |
2322 | * Process an ABORT. | |
2323 | * | |
2324 | * Section: 9.1 | |
2325 | * After checking the Verification Tag, the receiving endpoint shall | |
2326 | * remove the association from its record, and shall report the | |
2327 | * termination to its upper layer. | |
2328 | * | |
2329 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
2330 | * B) Rules for packet carrying ABORT: | |
2331 | * | |
2332 | * - The endpoint shall always fill in the Verification Tag field of the | |
2333 | * outbound packet with the destination endpoint's tag value if it | |
2334 | * is known. | |
2335 | * | |
2336 | * - If the ABORT is sent in response to an OOTB packet, the endpoint | |
2337 | * MUST follow the procedure described in Section 8.4. | |
2338 | * | |
2339 | * - The receiver MUST accept the packet if the Verification Tag | |
2340 | * matches either its own tag, OR the tag of its peer. Otherwise, the | |
2341 | * receiver MUST silently discard the packet and take no further | |
2342 | * action. | |
2343 | * | |
2344 | * Inputs | |
2345 | * (endpoint, asoc, chunk) | |
2346 | * | |
2347 | * Outputs | |
2348 | * (asoc, reply_msg, msg_up, timers, counters) | |
2349 | * | |
2350 | * The return value is the disposition of the chunk. | |
2351 | */ | |
2352 | sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, | |
2353 | const struct sctp_association *asoc, | |
2354 | const sctp_subtype_t type, | |
2355 | void *arg, | |
2356 | sctp_cmd_seq_t *commands) | |
2357 | { | |
2358 | struct sctp_chunk *chunk = arg; | |
1da177e4 LT |
2359 | |
2360 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2361 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2362 | ||
2363 | /* Make sure that the ABORT chunk has a valid length. | |
2364 | * Since this is an ABORT chunk, we have to discard it | |
2365 | * because of the following text: | |
2366 | * RFC 2960, Section 3.3.7 | |
2367 | * If an endpoint receives an ABORT with a format error or for an | |
2368 | * association that doesn't exist, it MUST silently discard it. | |
2369 | * Becasue the length is "invalid", we can't really discard just | |
2370 | * as we do not know its true length. So, to be safe, discard the | |
2371 | * packet. | |
2372 | */ | |
2373 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2374 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2375 | ||
75205f47 VY |
2376 | /* ADD-IP: Special case for ABORT chunks |
2377 | * F4) One special consideration is that ABORT Chunks arriving | |
2378 | * destined to the IP address being deleted MUST be | |
2379 | * ignored (see Section 5.3.1 for further details). | |
2380 | */ | |
2381 | if (SCTP_ADDR_DEL == | |
2382 | sctp_bind_addr_state(&asoc->base.bind_addr, &chunk->dest)) | |
2383 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
2384 | ||
2385 | return __sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); | |
2386 | } | |
2387 | ||
2388 | static sctp_disposition_t __sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, | |
2389 | const struct sctp_association *asoc, | |
2390 | const sctp_subtype_t type, | |
2391 | void *arg, | |
2392 | sctp_cmd_seq_t *commands) | |
2393 | { | |
2394 | struct sctp_chunk *chunk = arg; | |
2395 | unsigned len; | |
2396 | __be16 error = SCTP_ERROR_NO_ERROR; | |
2397 | ||
1da177e4 LT |
2398 | /* See if we have an error cause code in the chunk. */ |
2399 | len = ntohs(chunk->chunk_hdr->length); | |
2400 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2401 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2402 | ||
8de8c873 | 2403 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); |
d808ad9a | 2404 | /* ASSOC_FAILED will DELETE_TCB. */ |
5be291fe | 2405 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error)); |
1da177e4 LT |
2406 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
2407 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
2408 | ||
2409 | return SCTP_DISPOSITION_ABORT; | |
2410 | } | |
2411 | ||
2412 | /* | |
2413 | * Process an ABORT. (COOKIE-WAIT state) | |
2414 | * | |
2415 | * See sctp_sf_do_9_1_abort() above. | |
2416 | */ | |
2417 | sctp_disposition_t sctp_sf_cookie_wait_abort(const struct sctp_endpoint *ep, | |
2418 | const struct sctp_association *asoc, | |
2419 | const sctp_subtype_t type, | |
2420 | void *arg, | |
2421 | sctp_cmd_seq_t *commands) | |
2422 | { | |
2423 | struct sctp_chunk *chunk = arg; | |
2424 | unsigned len; | |
f94c0198 | 2425 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 LT |
2426 | |
2427 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2428 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2429 | ||
2430 | /* Make sure that the ABORT chunk has a valid length. | |
2431 | * Since this is an ABORT chunk, we have to discard it | |
2432 | * because of the following text: | |
2433 | * RFC 2960, Section 3.3.7 | |
2434 | * If an endpoint receives an ABORT with a format error or for an | |
2435 | * association that doesn't exist, it MUST silently discard it. | |
2436 | * Becasue the length is "invalid", we can't really discard just | |
2437 | * as we do not know its true length. So, to be safe, discard the | |
2438 | * packet. | |
2439 | */ | |
2440 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2441 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2442 | ||
2443 | /* See if we have an error cause code in the chunk. */ | |
2444 | len = ntohs(chunk->chunk_hdr->length); | |
2445 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2446 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2447 | ||
8de8c873 SS |
2448 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, asoc, |
2449 | chunk->transport); | |
1da177e4 LT |
2450 | } |
2451 | ||
2452 | /* | |
2453 | * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state) | |
2454 | */ | |
2455 | sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(const struct sctp_endpoint *ep, | |
2456 | const struct sctp_association *asoc, | |
2457 | const sctp_subtype_t type, | |
2458 | void *arg, | |
2459 | sctp_cmd_seq_t *commands) | |
2460 | { | |
8de8c873 SS |
2461 | return sctp_stop_t1_and_abort(commands, SCTP_ERROR_NO_ERROR, |
2462 | ENOPROTOOPT, asoc, | |
3f7a87d2 | 2463 | (struct sctp_transport *)arg); |
1da177e4 LT |
2464 | } |
2465 | ||
2466 | /* | |
2467 | * Process an ABORT. (COOKIE-ECHOED state) | |
2468 | */ | |
2469 | sctp_disposition_t sctp_sf_cookie_echoed_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 | { | |
2475 | /* There is a single T1 timer, so we should be able to use | |
2476 | * common function with the COOKIE-WAIT state. | |
2477 | */ | |
2478 | return sctp_sf_cookie_wait_abort(ep, asoc, type, arg, commands); | |
2479 | } | |
2480 | ||
2481 | /* | |
2482 | * Stop T1 timer and abort association with "INIT failed". | |
2483 | * | |
2484 | * This is common code called by several sctp_sf_*_abort() functions above. | |
2485 | */ | |
52c1da39 | 2486 | static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, |
f94c0198 | 2487 | __be16 error, int sk_err, |
3f7a87d2 FF |
2488 | const struct sctp_association *asoc, |
2489 | struct sctp_transport *transport) | |
1da177e4 | 2490 | { |
3f7a87d2 | 2491 | SCTP_DEBUG_PRINTK("ABORT received (INIT).\n"); |
1da177e4 LT |
2492 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
2493 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
2494 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
2495 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2496 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
8de8c873 | 2497 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); |
1da177e4 LT |
2498 | /* CMD_INIT_FAILED will DELETE_TCB. */ |
2499 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 2500 | SCTP_PERR(error)); |
3f7a87d2 | 2501 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
2502 | } |
2503 | ||
2504 | /* | |
2505 | * sctp_sf_do_9_2_shut | |
2506 | * | |
2507 | * Section: 9.2 | |
2508 | * Upon the reception of the SHUTDOWN, the peer endpoint shall | |
2509 | * - enter the SHUTDOWN-RECEIVED state, | |
2510 | * | |
2511 | * - stop accepting new data from its SCTP user | |
2512 | * | |
2513 | * - verify, by checking the Cumulative TSN Ack field of the chunk, | |
2514 | * that all its outstanding DATA chunks have been received by the | |
2515 | * SHUTDOWN sender. | |
2516 | * | |
2517 | * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT | |
2518 | * send a SHUTDOWN in response to a ULP request. And should discard | |
2519 | * subsequent SHUTDOWN chunks. | |
2520 | * | |
2521 | * If there are still outstanding DATA chunks left, the SHUTDOWN | |
2522 | * receiver shall continue to follow normal data transmission | |
2523 | * procedures defined in Section 6 until all outstanding DATA chunks | |
2524 | * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept | |
2525 | * new data from its SCTP user. | |
2526 | * | |
2527 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2528 | * | |
2529 | * Inputs | |
2530 | * (endpoint, asoc, chunk) | |
2531 | * | |
2532 | * Outputs | |
2533 | * (asoc, reply_msg, msg_up, timers, counters) | |
2534 | * | |
2535 | * The return value is the disposition of the chunk. | |
2536 | */ | |
2537 | sctp_disposition_t sctp_sf_do_9_2_shutdown(const struct sctp_endpoint *ep, | |
2538 | const struct sctp_association *asoc, | |
2539 | const sctp_subtype_t type, | |
2540 | void *arg, | |
2541 | sctp_cmd_seq_t *commands) | |
2542 | { | |
2543 | struct sctp_chunk *chunk = arg; | |
2544 | sctp_shutdownhdr_t *sdh; | |
2545 | sctp_disposition_t disposition; | |
2546 | struct sctp_ulpevent *ev; | |
2547 | ||
2548 | if (!sctp_vtag_verify(chunk, asoc)) | |
2549 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2550 | ||
2551 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2552 | if (!sctp_chunk_length_valid(chunk, | |
2553 | sizeof(struct sctp_shutdown_chunk_t))) | |
2554 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2555 | commands); | |
2556 | ||
2557 | /* Convert the elaborate header. */ | |
2558 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
2559 | skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t)); | |
2560 | chunk->subh.shutdown_hdr = sdh; | |
2561 | ||
eb0e0076 SS |
2562 | /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT |
2563 | * When a peer sends a SHUTDOWN, SCTP delivers this notification to | |
2564 | * inform the application that it should cease sending data. | |
2565 | */ | |
2566 | ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC); | |
2567 | if (!ev) { | |
2568 | disposition = SCTP_DISPOSITION_NOMEM; | |
d808ad9a | 2569 | goto out; |
eb0e0076 SS |
2570 | } |
2571 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
2572 | ||
1da177e4 LT |
2573 | /* Upon the reception of the SHUTDOWN, the peer endpoint shall |
2574 | * - enter the SHUTDOWN-RECEIVED state, | |
2575 | * - stop accepting new data from its SCTP user | |
2576 | * | |
2577 | * [This is implicit in the new state.] | |
2578 | */ | |
2579 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2580 | SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED)); | |
2581 | disposition = SCTP_DISPOSITION_CONSUME; | |
2582 | ||
2583 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
2584 | disposition = sctp_sf_do_9_2_shutdown_ack(ep, asoc, type, | |
2585 | arg, commands); | |
2586 | } | |
2587 | ||
2588 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
2589 | goto out; | |
2590 | ||
2591 | /* - verify, by checking the Cumulative TSN Ack field of the | |
2592 | * chunk, that all its outstanding DATA chunks have been | |
2593 | * received by the SHUTDOWN sender. | |
2594 | */ | |
2595 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2178eda8 | 2596 | SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack)); |
1da177e4 | 2597 | |
1da177e4 LT |
2598 | out: |
2599 | return disposition; | |
2600 | } | |
2601 | ||
2602 | /* RFC 2960 9.2 | |
2603 | * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk | |
2604 | * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination | |
2605 | * transport addresses (either in the IP addresses or in the INIT chunk) | |
2606 | * that belong to this association, it should discard the INIT chunk and | |
2607 | * retransmit the SHUTDOWN ACK chunk. | |
2608 | */ | |
2609 | sctp_disposition_t sctp_sf_do_9_2_reshutack(const struct sctp_endpoint *ep, | |
2610 | const struct sctp_association *asoc, | |
2611 | const sctp_subtype_t type, | |
2612 | void *arg, | |
2613 | sctp_cmd_seq_t *commands) | |
2614 | { | |
2615 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
2616 | struct sctp_chunk *reply; | |
2617 | ||
ece25dfa VY |
2618 | /* Make sure that the chunk has a valid length */ |
2619 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
2620 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2621 | commands); | |
2622 | ||
1da177e4 LT |
2623 | /* Since we are not going to really process this INIT, there |
2624 | * is no point in verifying chunk boundries. Just generate | |
2625 | * the SHUTDOWN ACK. | |
2626 | */ | |
2627 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
2628 | if (NULL == reply) | |
2629 | goto nomem; | |
2630 | ||
2631 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
2632 | * the T2-SHUTDOWN timer. | |
2633 | */ | |
2634 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
2635 | ||
2636 | /* and restart the T2-shutdown timer. */ | |
2637 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2638 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2639 | ||
2640 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2641 | ||
2642 | return SCTP_DISPOSITION_CONSUME; | |
2643 | nomem: | |
2644 | return SCTP_DISPOSITION_NOMEM; | |
2645 | } | |
2646 | ||
2647 | /* | |
2648 | * sctp_sf_do_ecn_cwr | |
2649 | * | |
2650 | * Section: Appendix A: Explicit Congestion Notification | |
2651 | * | |
2652 | * CWR: | |
2653 | * | |
2654 | * RFC 2481 details a specific bit for a sender to send in the header of | |
2655 | * its next outbound TCP segment to indicate to its peer that it has | |
2656 | * reduced its congestion window. This is termed the CWR bit. For | |
2657 | * SCTP the same indication is made by including the CWR chunk. | |
2658 | * This chunk contains one data element, i.e. the TSN number that | |
2659 | * was sent in the ECNE chunk. This element represents the lowest | |
2660 | * TSN number in the datagram that was originally marked with the | |
2661 | * CE bit. | |
2662 | * | |
2663 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2664 | * Inputs | |
2665 | * (endpoint, asoc, chunk) | |
2666 | * | |
2667 | * Outputs | |
2668 | * (asoc, reply_msg, msg_up, timers, counters) | |
2669 | * | |
2670 | * The return value is the disposition of the chunk. | |
2671 | */ | |
2672 | sctp_disposition_t sctp_sf_do_ecn_cwr(const struct sctp_endpoint *ep, | |
2673 | const struct sctp_association *asoc, | |
2674 | const sctp_subtype_t type, | |
2675 | void *arg, | |
2676 | sctp_cmd_seq_t *commands) | |
2677 | { | |
2678 | sctp_cwrhdr_t *cwr; | |
2679 | struct sctp_chunk *chunk = arg; | |
34bcca28 | 2680 | u32 lowest_tsn; |
1da177e4 LT |
2681 | |
2682 | if (!sctp_vtag_verify(chunk, asoc)) | |
2683 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2684 | ||
2685 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2686 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2687 | commands); | |
d808ad9a | 2688 | |
1da177e4 LT |
2689 | cwr = (sctp_cwrhdr_t *) chunk->skb->data; |
2690 | skb_pull(chunk->skb, sizeof(sctp_cwrhdr_t)); | |
2691 | ||
34bcca28 | 2692 | lowest_tsn = ntohl(cwr->lowest_tsn); |
1da177e4 LT |
2693 | |
2694 | /* Does this CWR ack the last sent congestion notification? */ | |
34bcca28 | 2695 | if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) { |
1da177e4 LT |
2696 | /* Stop sending ECNE. */ |
2697 | sctp_add_cmd_sf(commands, | |
2698 | SCTP_CMD_ECN_CWR, | |
34bcca28 | 2699 | SCTP_U32(lowest_tsn)); |
1da177e4 LT |
2700 | } |
2701 | return SCTP_DISPOSITION_CONSUME; | |
2702 | } | |
2703 | ||
2704 | /* | |
2705 | * sctp_sf_do_ecne | |
2706 | * | |
2707 | * Section: Appendix A: Explicit Congestion Notification | |
2708 | * | |
2709 | * ECN-Echo | |
2710 | * | |
2711 | * RFC 2481 details a specific bit for a receiver to send back in its | |
2712 | * TCP acknowledgements to notify the sender of the Congestion | |
2713 | * Experienced (CE) bit having arrived from the network. For SCTP this | |
2714 | * same indication is made by including the ECNE chunk. This chunk | |
2715 | * contains one data element, i.e. the lowest TSN associated with the IP | |
2716 | * datagram marked with the CE bit..... | |
2717 | * | |
2718 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2719 | * Inputs | |
2720 | * (endpoint, asoc, chunk) | |
2721 | * | |
2722 | * Outputs | |
2723 | * (asoc, reply_msg, msg_up, timers, counters) | |
2724 | * | |
2725 | * The return value is the disposition of the chunk. | |
2726 | */ | |
2727 | sctp_disposition_t sctp_sf_do_ecne(const struct sctp_endpoint *ep, | |
2728 | const struct sctp_association *asoc, | |
2729 | const sctp_subtype_t type, | |
2730 | void *arg, | |
2731 | sctp_cmd_seq_t *commands) | |
2732 | { | |
2733 | sctp_ecnehdr_t *ecne; | |
2734 | struct sctp_chunk *chunk = arg; | |
2735 | ||
2736 | if (!sctp_vtag_verify(chunk, asoc)) | |
2737 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2738 | ||
2739 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2740 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2741 | commands); | |
2742 | ||
2743 | ecne = (sctp_ecnehdr_t *) chunk->skb->data; | |
2744 | skb_pull(chunk->skb, sizeof(sctp_ecnehdr_t)); | |
2745 | ||
2746 | /* If this is a newer ECNE than the last CWR packet we sent out */ | |
2747 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE, | |
2748 | SCTP_U32(ntohl(ecne->lowest_tsn))); | |
2749 | ||
2750 | return SCTP_DISPOSITION_CONSUME; | |
2751 | } | |
2752 | ||
2753 | /* | |
2754 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
2755 | * | |
2756 | * The SCTP endpoint MUST always acknowledge the reception of each valid | |
2757 | * DATA chunk. | |
2758 | * | |
2759 | * The guidelines on delayed acknowledgement algorithm specified in | |
2760 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
2761 | * acknowledgement SHOULD be generated for at least every second packet | |
2762 | * (not every second DATA chunk) received, and SHOULD be generated within | |
2763 | * 200 ms of the arrival of any unacknowledged DATA chunk. In some | |
2764 | * situations it may be beneficial for an SCTP transmitter to be more | |
2765 | * conservative than the algorithms detailed in this document allow. | |
2766 | * However, an SCTP transmitter MUST NOT be more aggressive than the | |
2767 | * following algorithms allow. | |
2768 | * | |
2769 | * A SCTP receiver MUST NOT generate more than one SACK for every | |
2770 | * incoming packet, other than to update the offered window as the | |
2771 | * receiving application consumes new data. | |
2772 | * | |
2773 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2774 | * | |
2775 | * Inputs | |
2776 | * (endpoint, asoc, chunk) | |
2777 | * | |
2778 | * Outputs | |
2779 | * (asoc, reply_msg, msg_up, timers, counters) | |
2780 | * | |
2781 | * The return value is the disposition of the chunk. | |
2782 | */ | |
2783 | sctp_disposition_t sctp_sf_eat_data_6_2(const struct sctp_endpoint *ep, | |
2784 | const struct sctp_association *asoc, | |
2785 | const sctp_subtype_t type, | |
2786 | void *arg, | |
2787 | sctp_cmd_seq_t *commands) | |
2788 | { | |
2789 | struct sctp_chunk *chunk = arg; | |
2790 | int error; | |
2791 | ||
2792 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2793 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2794 | SCTP_NULL()); | |
2795 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 2796 | } |
1da177e4 LT |
2797 | |
2798 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
2799 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2800 | commands); | |
2801 | ||
2802 | error = sctp_eat_data(asoc, chunk, commands ); | |
2803 | switch (error) { | |
2804 | case SCTP_IERROR_NO_ERROR: | |
2805 | break; | |
2806 | case SCTP_IERROR_HIGH_TSN: | |
2807 | case SCTP_IERROR_BAD_STREAM: | |
ac0b0462 | 2808 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2809 | goto discard_noforce; |
2810 | case SCTP_IERROR_DUP_TSN: | |
2811 | case SCTP_IERROR_IGNORE_TSN: | |
ac0b0462 | 2812 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2813 | goto discard_force; |
2814 | case SCTP_IERROR_NO_DATA: | |
2815 | goto consume; | |
2816 | default: | |
2817 | BUG(); | |
2818 | } | |
2819 | ||
2820 | if (asoc->autoclose) { | |
2821 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2822 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
2823 | } | |
2824 | ||
2825 | /* If this is the last chunk in a packet, we need to count it | |
2826 | * toward sack generation. Note that we need to SACK every | |
2827 | * OTHER packet containing data chunks, EVEN IF WE DISCARD | |
2828 | * THEM. We elect to NOT generate SACK's if the chunk fails | |
2829 | * the verification tag test. | |
2830 | * | |
2831 | * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2832 | * | |
2833 | * The SCTP endpoint MUST always acknowledge the reception of | |
2834 | * each valid DATA chunk. | |
2835 | * | |
2836 | * The guidelines on delayed acknowledgement algorithm | |
2837 | * specified in Section 4.2 of [RFC2581] SHOULD be followed. | |
2838 | * Specifically, an acknowledgement SHOULD be generated for at | |
2839 | * least every second packet (not every second DATA chunk) | |
2840 | * received, and SHOULD be generated within 200 ms of the | |
2841 | * arrival of any unacknowledged DATA chunk. In some | |
2842 | * situations it may be beneficial for an SCTP transmitter to | |
2843 | * be more conservative than the algorithms detailed in this | |
2844 | * document allow. However, an SCTP transmitter MUST NOT be | |
2845 | * more aggressive than the following algorithms allow. | |
2846 | */ | |
52ccb8e9 | 2847 | if (chunk->end_of_packet) |
1da177e4 LT |
2848 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); |
2849 | ||
1da177e4 LT |
2850 | return SCTP_DISPOSITION_CONSUME; |
2851 | ||
2852 | discard_force: | |
2853 | /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2854 | * | |
2855 | * When a packet arrives with duplicate DATA chunk(s) and with | |
2856 | * no new DATA chunk(s), the endpoint MUST immediately send a | |
2857 | * SACK with no delay. If a packet arrives with duplicate | |
2858 | * DATA chunk(s) bundled with new DATA chunks, the endpoint | |
2859 | * MAY immediately send a SACK. Normally receipt of duplicate | |
2860 | * DATA chunks will occur when the original SACK chunk was lost | |
2861 | * and the peer's RTO has expired. The duplicate TSN number(s) | |
2862 | * SHOULD be reported in the SACK as duplicate. | |
2863 | */ | |
2864 | /* In our case, we split the MAY SACK advice up whether or not | |
2865 | * the last chunk is a duplicate.' | |
2866 | */ | |
2867 | if (chunk->end_of_packet) | |
2868 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
2869 | return SCTP_DISPOSITION_DISCARD; | |
2870 | ||
2871 | discard_noforce: | |
52ccb8e9 | 2872 | if (chunk->end_of_packet) |
1da177e4 LT |
2873 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); |
2874 | ||
1da177e4 LT |
2875 | return SCTP_DISPOSITION_DISCARD; |
2876 | consume: | |
2877 | return SCTP_DISPOSITION_CONSUME; | |
d808ad9a | 2878 | |
1da177e4 LT |
2879 | } |
2880 | ||
2881 | /* | |
2882 | * sctp_sf_eat_data_fast_4_4 | |
2883 | * | |
2884 | * Section: 4 (4) | |
2885 | * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received | |
2886 | * DATA chunks without delay. | |
2887 | * | |
2888 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2889 | * Inputs | |
2890 | * (endpoint, asoc, chunk) | |
2891 | * | |
2892 | * Outputs | |
2893 | * (asoc, reply_msg, msg_up, timers, counters) | |
2894 | * | |
2895 | * The return value is the disposition of the chunk. | |
2896 | */ | |
2897 | sctp_disposition_t sctp_sf_eat_data_fast_4_4(const struct sctp_endpoint *ep, | |
2898 | const struct sctp_association *asoc, | |
2899 | const sctp_subtype_t type, | |
2900 | void *arg, | |
2901 | sctp_cmd_seq_t *commands) | |
2902 | { | |
2903 | struct sctp_chunk *chunk = arg; | |
2904 | int error; | |
2905 | ||
2906 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2907 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2908 | SCTP_NULL()); | |
2909 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2910 | } | |
2911 | ||
2912 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
2913 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2914 | commands); | |
2915 | ||
2916 | error = sctp_eat_data(asoc, chunk, commands ); | |
2917 | switch (error) { | |
2918 | case SCTP_IERROR_NO_ERROR: | |
2919 | case SCTP_IERROR_HIGH_TSN: | |
2920 | case SCTP_IERROR_DUP_TSN: | |
2921 | case SCTP_IERROR_IGNORE_TSN: | |
2922 | case SCTP_IERROR_BAD_STREAM: | |
2923 | break; | |
2924 | case SCTP_IERROR_NO_DATA: | |
2925 | goto consume; | |
2926 | default: | |
2927 | BUG(); | |
2928 | } | |
2929 | ||
2930 | /* Go a head and force a SACK, since we are shutting down. */ | |
2931 | ||
2932 | /* Implementor's Guide. | |
2933 | * | |
2934 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
2935 | * respond to each received packet containing one or more DATA chunk(s) | |
2936 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
2937 | */ | |
2938 | if (chunk->end_of_packet) { | |
2939 | /* We must delay the chunk creation since the cumulative | |
2940 | * TSN has not been updated yet. | |
2941 | */ | |
2942 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
2943 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
2944 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2945 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2946 | } | |
2947 | ||
2948 | consume: | |
2949 | return SCTP_DISPOSITION_CONSUME; | |
2950 | } | |
2951 | ||
2952 | /* | |
2953 | * Section: 6.2 Processing a Received SACK | |
2954 | * D) Any time a SACK arrives, the endpoint performs the following: | |
2955 | * | |
2956 | * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point, | |
2957 | * then drop the SACK. Since Cumulative TSN Ack is monotonically | |
2958 | * increasing, a SACK whose Cumulative TSN Ack is less than the | |
2959 | * Cumulative TSN Ack Point indicates an out-of-order SACK. | |
2960 | * | |
2961 | * ii) Set rwnd equal to the newly received a_rwnd minus the number | |
2962 | * of bytes still outstanding after processing the Cumulative TSN Ack | |
2963 | * and the Gap Ack Blocks. | |
2964 | * | |
2965 | * iii) If the SACK is missing a TSN that was previously | |
2966 | * acknowledged via a Gap Ack Block (e.g., the data receiver | |
2967 | * reneged on the data), then mark the corresponding DATA chunk | |
2968 | * as available for retransmit: Mark it as missing for fast | |
2969 | * retransmit as described in Section 7.2.4 and if no retransmit | |
2970 | * timer is running for the destination address to which the DATA | |
2971 | * chunk was originally transmitted, then T3-rtx is started for | |
2972 | * that destination address. | |
2973 | * | |
2974 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2975 | * | |
2976 | * Inputs | |
2977 | * (endpoint, asoc, chunk) | |
2978 | * | |
2979 | * Outputs | |
2980 | * (asoc, reply_msg, msg_up, timers, counters) | |
2981 | * | |
2982 | * The return value is the disposition of the chunk. | |
2983 | */ | |
2984 | sctp_disposition_t sctp_sf_eat_sack_6_2(const struct sctp_endpoint *ep, | |
2985 | const struct sctp_association *asoc, | |
2986 | const sctp_subtype_t type, | |
2987 | void *arg, | |
2988 | sctp_cmd_seq_t *commands) | |
2989 | { | |
2990 | struct sctp_chunk *chunk = arg; | |
2991 | sctp_sackhdr_t *sackh; | |
2992 | __u32 ctsn; | |
2993 | ||
2994 | if (!sctp_vtag_verify(chunk, asoc)) | |
2995 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2996 | ||
2997 | /* Make sure that the SACK chunk has a valid length. */ | |
2998 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t))) | |
2999 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3000 | commands); | |
3001 | ||
3002 | /* Pull the SACK chunk from the data buffer */ | |
3003 | sackh = sctp_sm_pull_sack(chunk); | |
3004 | /* Was this a bogus SACK? */ | |
3005 | if (!sackh) | |
3006 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3007 | chunk->subh.sack_hdr = sackh; | |
3008 | ctsn = ntohl(sackh->cum_tsn_ack); | |
3009 | ||
3010 | /* i) If Cumulative TSN Ack is less than the Cumulative TSN | |
3011 | * Ack Point, then drop the SACK. Since Cumulative TSN | |
3012 | * Ack is monotonically increasing, a SACK whose | |
3013 | * Cumulative TSN Ack is less than the Cumulative TSN Ack | |
3014 | * Point indicates an out-of-order SACK. | |
3015 | */ | |
3016 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
3017 | SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); | |
3018 | SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); | |
3019 | return SCTP_DISPOSITION_DISCARD; | |
3020 | } | |
3021 | ||
aecedeab WY |
3022 | /* If Cumulative TSN Ack beyond the max tsn currently |
3023 | * send, terminating the association and respond to the | |
3024 | * sender with an ABORT. | |
3025 | */ | |
3026 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
3027 | return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); | |
3028 | ||
1da177e4 LT |
3029 | /* Return this SACK for further processing. */ |
3030 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_SACKH(sackh)); | |
3031 | ||
3032 | /* Note: We do the rest of the work on the PROCESS_SACK | |
3033 | * sideeffect. | |
3034 | */ | |
3035 | return SCTP_DISPOSITION_CONSUME; | |
3036 | } | |
3037 | ||
3038 | /* | |
3039 | * Generate an ABORT in response to a packet. | |
3040 | * | |
047a2428 | 3041 | * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41 |
1da177e4 | 3042 | * |
047a2428 JF |
3043 | * 8) The receiver should respond to the sender of the OOTB packet with |
3044 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3045 | * MUST fill in the Verification Tag field of the outbound packet | |
3046 | * with the value found in the Verification Tag field of the OOTB | |
3047 | * packet and set the T-bit in the Chunk Flags to indicate that the | |
3048 | * Verification Tag is reflected. After sending this ABORT, the | |
3049 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3050 | * no further action. | |
1da177e4 LT |
3051 | * |
3052 | * Verification Tag: | |
3053 | * | |
3054 | * The return value is the disposition of the chunk. | |
3055 | */ | |
ece25dfa | 3056 | static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, |
1da177e4 LT |
3057 | const struct sctp_association *asoc, |
3058 | const sctp_subtype_t type, | |
3059 | void *arg, | |
3060 | sctp_cmd_seq_t *commands) | |
3061 | { | |
3062 | struct sctp_packet *packet = NULL; | |
3063 | struct sctp_chunk *chunk = arg; | |
3064 | struct sctp_chunk *abort; | |
3065 | ||
3066 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
3067 | ||
3068 | if (packet) { | |
3069 | /* Make an ABORT. The T bit will be set if the asoc | |
3070 | * is NULL. | |
3071 | */ | |
d808ad9a | 3072 | abort = sctp_make_abort(asoc, chunk, 0); |
1da177e4 LT |
3073 | if (!abort) { |
3074 | sctp_ootb_pkt_free(packet); | |
3075 | return SCTP_DISPOSITION_NOMEM; | |
3076 | } | |
3077 | ||
047a2428 JF |
3078 | /* Reflect vtag if T-Bit is set */ |
3079 | if (sctp_test_T_bit(abort)) | |
3080 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3081 | ||
1da177e4 LT |
3082 | /* Set the skb to the belonging sock for accounting. */ |
3083 | abort->skb->sk = ep->base.sk; | |
3084 | ||
3085 | sctp_packet_append_chunk(packet, abort); | |
3086 | ||
3087 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3088 | SCTP_PACKET(packet)); | |
3089 | ||
3090 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
3091 | ||
d3f25968 | 3092 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); |
1da177e4 LT |
3093 | return SCTP_DISPOSITION_CONSUME; |
3094 | } | |
3095 | ||
3096 | return SCTP_DISPOSITION_NOMEM; | |
3097 | } | |
3098 | ||
3099 | /* | |
3100 | * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR | |
3101 | * event as ULP notification for each cause included in the chunk. | |
3102 | * | |
3103 | * API 5.3.1.3 - SCTP_REMOTE_ERROR | |
3104 | * | |
3105 | * The return value is the disposition of the chunk. | |
3106 | */ | |
3107 | sctp_disposition_t sctp_sf_operr_notify(const struct sctp_endpoint *ep, | |
3108 | const struct sctp_association *asoc, | |
3109 | const sctp_subtype_t type, | |
3110 | void *arg, | |
3111 | sctp_cmd_seq_t *commands) | |
3112 | { | |
3113 | struct sctp_chunk *chunk = arg; | |
3114 | struct sctp_ulpevent *ev; | |
3115 | ||
3116 | if (!sctp_vtag_verify(chunk, asoc)) | |
3117 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3118 | ||
3119 | /* Make sure that the ERROR chunk has a valid length. */ | |
3120 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
3121 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3122 | commands); | |
3123 | ||
3124 | while (chunk->chunk_end > chunk->skb->data) { | |
3125 | ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0, | |
3126 | GFP_ATOMIC); | |
3127 | if (!ev) | |
3128 | goto nomem; | |
3129 | ||
bc09dff1 IJ |
3130 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
3131 | SCTP_ULPEVENT(ev)); | |
1da177e4 | 3132 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR, |
d808ad9a | 3133 | SCTP_CHUNK(chunk)); |
1da177e4 LT |
3134 | } |
3135 | return SCTP_DISPOSITION_CONSUME; | |
3136 | ||
3137 | nomem: | |
3138 | return SCTP_DISPOSITION_NOMEM; | |
3139 | } | |
3140 | ||
3141 | /* | |
3142 | * Process an inbound SHUTDOWN ACK. | |
3143 | * | |
3144 | * From Section 9.2: | |
3145 | * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3146 | * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its | |
3147 | * peer, and remove all record of the association. | |
3148 | * | |
3149 | * The return value is the disposition. | |
3150 | */ | |
3151 | sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep, | |
3152 | const struct sctp_association *asoc, | |
3153 | const sctp_subtype_t type, | |
3154 | void *arg, | |
3155 | sctp_cmd_seq_t *commands) | |
3156 | { | |
3157 | struct sctp_chunk *chunk = arg; | |
3158 | struct sctp_chunk *reply; | |
3159 | struct sctp_ulpevent *ev; | |
3160 | ||
3161 | if (!sctp_vtag_verify(chunk, asoc)) | |
3162 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3163 | ||
3164 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3165 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3166 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3167 | commands); | |
1da177e4 LT |
3168 | /* 10.2 H) SHUTDOWN COMPLETE notification |
3169 | * | |
3170 | * When SCTP completes the shutdown procedures (section 9.2) this | |
3171 | * notification is passed to the upper layer. | |
3172 | */ | |
3173 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 3174 | 0, 0, 0, NULL, GFP_ATOMIC); |
1da177e4 LT |
3175 | if (!ev) |
3176 | goto nomem; | |
3177 | ||
df7deeb5 VY |
3178 | /* ...send a SHUTDOWN COMPLETE chunk to its peer, */ |
3179 | reply = sctp_make_shutdown_complete(asoc, chunk); | |
3180 | if (!reply) | |
3181 | goto nomem_chunk; | |
3182 | ||
3183 | /* Do all the commands now (after allocation), so that we | |
3184 | * have consistent state if memory allocation failes | |
3185 | */ | |
1da177e4 LT |
3186 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
3187 | ||
3188 | /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3189 | * stop the T2-shutdown timer, | |
3190 | */ | |
3191 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3192 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3193 | ||
3194 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3195 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
3196 | ||
1da177e4 LT |
3197 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
3198 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
3199 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
3200 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3201 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
3202 | ||
3203 | /* ...and remove all record of the association. */ | |
3204 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
3205 | return SCTP_DISPOSITION_DELETE_TCB; | |
3206 | ||
df7deeb5 VY |
3207 | nomem_chunk: |
3208 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
3209 | nomem: |
3210 | return SCTP_DISPOSITION_NOMEM; | |
3211 | } | |
3212 | ||
3213 | /* | |
047a2428 JF |
3214 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41. |
3215 | * | |
1da177e4 LT |
3216 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
3217 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. | |
3218 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3219 | * packet must fill in the Verification Tag field of the outbound | |
3220 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
047a2428 JF |
3221 | * set the T-bit in the Chunk Flags to indicate that the Verification |
3222 | * Tag is reflected. | |
1da177e4 LT |
3223 | * |
3224 | * 8) The receiver should respond to the sender of the OOTB packet with | |
3225 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3226 | * MUST fill in the Verification Tag field of the outbound packet | |
3227 | * with the value found in the Verification Tag field of the OOTB | |
047a2428 JF |
3228 | * packet and set the T-bit in the Chunk Flags to indicate that the |
3229 | * Verification Tag is reflected. After sending this ABORT, the | |
3230 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3231 | * no further action. | |
1da177e4 LT |
3232 | */ |
3233 | sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep, | |
3234 | const struct sctp_association *asoc, | |
3235 | const sctp_subtype_t type, | |
3236 | void *arg, | |
3237 | sctp_cmd_seq_t *commands) | |
3238 | { | |
3239 | struct sctp_chunk *chunk = arg; | |
3240 | struct sk_buff *skb = chunk->skb; | |
3241 | sctp_chunkhdr_t *ch; | |
3242 | __u8 *ch_end; | |
3243 | int ootb_shut_ack = 0; | |
3244 | ||
3245 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
3246 | ||
3247 | ch = (sctp_chunkhdr_t *) chunk->chunk_hdr; | |
3248 | do { | |
ece25dfa | 3249 | /* Report violation if the chunk is less then minimal */ |
1da177e4 | 3250 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
ece25dfa VY |
3251 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, |
3252 | commands); | |
1da177e4 | 3253 | |
ece25dfa VY |
3254 | /* Now that we know we at least have a chunk header, |
3255 | * do things that are type appropriate. | |
3256 | */ | |
1da177e4 LT |
3257 | if (SCTP_CID_SHUTDOWN_ACK == ch->type) |
3258 | ootb_shut_ack = 1; | |
3259 | ||
3260 | /* RFC 2960, Section 3.3.7 | |
3261 | * Moreover, under any circumstances, an endpoint that | |
3262 | * receives an ABORT MUST NOT respond to that ABORT by | |
3263 | * sending an ABORT of its own. | |
3264 | */ | |
3265 | if (SCTP_CID_ABORT == ch->type) | |
3266 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 3267 | |
ece25dfa VY |
3268 | /* Report violation if chunk len overflows */ |
3269 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); | |
3270 | if (ch_end > skb_tail_pointer(skb)) | |
3271 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3272 | commands); | |
3273 | ||
1da177e4 | 3274 | ch = (sctp_chunkhdr_t *) ch_end; |
27a884dc | 3275 | } while (ch_end < skb_tail_pointer(skb)); |
1da177e4 LT |
3276 | |
3277 | if (ootb_shut_ack) | |
d3f25968 | 3278 | return sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands); |
1da177e4 | 3279 | else |
d3f25968 | 3280 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
1da177e4 LT |
3281 | } |
3282 | ||
3283 | /* | |
3284 | * Handle an "Out of the blue" SHUTDOWN ACK. | |
3285 | * | |
047a2428 JF |
3286 | * Section: 8.4 5, sctpimpguide 2.41. |
3287 | * | |
1da177e4 | 3288 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
047a2428 JF |
3289 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. |
3290 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3291 | * packet must fill in the Verification Tag field of the outbound | |
3292 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
3293 | * set the T-bit in the Chunk Flags to indicate that the Verification | |
3294 | * Tag is reflected. | |
1da177e4 LT |
3295 | * |
3296 | * Inputs | |
3297 | * (endpoint, asoc, type, arg, commands) | |
3298 | * | |
3299 | * Outputs | |
3300 | * (sctp_disposition_t) | |
3301 | * | |
3302 | * The return value is the disposition of the chunk. | |
3303 | */ | |
3304 | static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, | |
3305 | const struct sctp_association *asoc, | |
3306 | const sctp_subtype_t type, | |
3307 | void *arg, | |
3308 | sctp_cmd_seq_t *commands) | |
3309 | { | |
3310 | struct sctp_packet *packet = NULL; | |
3311 | struct sctp_chunk *chunk = arg; | |
3312 | struct sctp_chunk *shut; | |
3313 | ||
3314 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
3315 | ||
3316 | if (packet) { | |
3317 | /* Make an SHUTDOWN_COMPLETE. | |
d808ad9a YH |
3318 | * The T bit will be set if the asoc is NULL. |
3319 | */ | |
1da177e4 LT |
3320 | shut = sctp_make_shutdown_complete(asoc, chunk); |
3321 | if (!shut) { | |
3322 | sctp_ootb_pkt_free(packet); | |
3323 | return SCTP_DISPOSITION_NOMEM; | |
3324 | } | |
3325 | ||
047a2428 JF |
3326 | /* Reflect vtag if T-Bit is set */ |
3327 | if (sctp_test_T_bit(shut)) | |
3328 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3329 | ||
1da177e4 LT |
3330 | /* Set the skb to the belonging sock for accounting. */ |
3331 | shut->skb->sk = ep->base.sk; | |
3332 | ||
3333 | sctp_packet_append_chunk(packet, shut); | |
3334 | ||
3335 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3336 | SCTP_PACKET(packet)); | |
3337 | ||
3338 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
3339 | ||
3340 | /* If the chunk length is invalid, we don't want to process | |
3341 | * the reset of the packet. | |
3342 | */ | |
3343 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3344 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3345 | ||
d3f25968 VY |
3346 | /* We need to discard the rest of the packet to prevent |
3347 | * potential bomming attacks from additional bundled chunks. | |
3348 | * This is documented in SCTP Threats ID. | |
3349 | */ | |
3350 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1da177e4 LT |
3351 | } |
3352 | ||
3353 | return SCTP_DISPOSITION_NOMEM; | |
3354 | } | |
3355 | ||
3356 | /* | |
3357 | * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state. | |
3358 | * | |
3359 | * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK | |
3360 | * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the | |
3361 | * procedures in section 8.4 SHOULD be followed, in other words it | |
3362 | * should be treated as an Out Of The Blue packet. | |
3363 | * [This means that we do NOT check the Verification Tag on these | |
3364 | * chunks. --piggy ] | |
3365 | * | |
3366 | */ | |
3367 | sctp_disposition_t sctp_sf_do_8_5_1_E_sa(const struct sctp_endpoint *ep, | |
3368 | const struct sctp_association *asoc, | |
3369 | const sctp_subtype_t type, | |
3370 | void *arg, | |
3371 | sctp_cmd_seq_t *commands) | |
3372 | { | |
ece25dfa VY |
3373 | struct sctp_chunk *chunk = arg; |
3374 | ||
3375 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3376 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3377 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3378 | commands); | |
3379 | ||
1da177e4 LT |
3380 | /* Although we do have an association in this case, it corresponds |
3381 | * to a restarted association. So the packet is treated as an OOTB | |
3382 | * packet and the state function that handles OOTB SHUTDOWN_ACK is | |
3383 | * called with a NULL association. | |
3384 | */ | |
8190f89d WY |
3385 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); |
3386 | ||
1da177e4 LT |
3387 | return sctp_sf_shut_8_4_5(ep, NULL, type, arg, commands); |
3388 | } | |
3389 | ||
3390 | /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */ | |
3391 | sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep, | |
3392 | const struct sctp_association *asoc, | |
3393 | const sctp_subtype_t type, void *arg, | |
3394 | sctp_cmd_seq_t *commands) | |
3395 | { | |
3396 | struct sctp_chunk *chunk = arg; | |
3397 | struct sctp_chunk *asconf_ack = NULL; | |
6f4c618d | 3398 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 | 3399 | sctp_addiphdr_t *hdr; |
6f4c618d | 3400 | union sctp_addr_param *addr_param; |
1da177e4 | 3401 | __u32 serial; |
6f4c618d | 3402 | int length; |
1da177e4 LT |
3403 | |
3404 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3405 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3406 | SCTP_NULL()); | |
3407 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3408 | } | |
3409 | ||
6afd2e83 VY |
3410 | /* ADD-IP: Section 4.1.1 |
3411 | * This chunk MUST be sent in an authenticated way by using | |
3412 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3413 | * is received unauthenticated it MUST be silently discarded as | |
3414 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3415 | */ | |
3416 | if (!sctp_addip_noauth && !chunk->auth) | |
3417 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
3418 | ||
1da177e4 LT |
3419 | /* Make sure that the ASCONF ADDIP chunk has a valid length. */ |
3420 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t))) | |
3421 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3422 | commands); | |
3423 | ||
3424 | hdr = (sctp_addiphdr_t *)chunk->skb->data; | |
3425 | serial = ntohl(hdr->serial); | |
3426 | ||
6f4c618d WY |
3427 | addr_param = (union sctp_addr_param *)hdr->params; |
3428 | length = ntohs(addr_param->p.length); | |
3429 | if (length < sizeof(sctp_paramhdr_t)) | |
ba016670 | 3430 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
6f4c618d WY |
3431 | (void *)addr_param, commands); |
3432 | ||
3433 | /* Verify the ASCONF chunk before processing it. */ | |
3434 | if (!sctp_verify_asconf(asoc, | |
a08de64d VY |
3435 | (sctp_paramhdr_t *)((void *)addr_param + length), |
3436 | (void *)chunk->chunk_end, | |
3437 | &err_param)) | |
ba016670 WY |
3438 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
3439 | (void *)err_param, commands); | |
6f4c618d | 3440 | |
a08de64d | 3441 | /* ADDIP 5.2 E1) Compare the value of the serial number to the value |
1da177e4 | 3442 | * the endpoint stored in a new association variable |
d808ad9a | 3443 | * 'Peer-Serial-Number'. |
1da177e4 LT |
3444 | */ |
3445 | if (serial == asoc->peer.addip_serial + 1) { | |
a08de64d VY |
3446 | /* If this is the first instance of ASCONF in the packet, |
3447 | * we can clean our old ASCONF-ACKs. | |
3448 | */ | |
3449 | if (!chunk->has_asconf) | |
3450 | sctp_assoc_clean_asconf_ack_cache(asoc); | |
3451 | ||
3452 | /* ADDIP 5.2 E4) When the Sequence Number matches the next one | |
3453 | * expected, process the ASCONF as described below and after | |
3454 | * processing the ASCONF Chunk, append an ASCONF-ACK Chunk to | |
3455 | * the response packet and cache a copy of it (in the event it | |
3456 | * later needs to be retransmitted). | |
3457 | * | |
3458 | * Essentially, do V1-V5. | |
1da177e4 LT |
3459 | */ |
3460 | asconf_ack = sctp_process_asconf((struct sctp_association *) | |
3461 | asoc, chunk); | |
3462 | if (!asconf_ack) | |
3463 | return SCTP_DISPOSITION_NOMEM; | |
a08de64d VY |
3464 | } else if (serial < asoc->peer.addip_serial + 1) { |
3465 | /* ADDIP 5.2 E2) | |
3466 | * If the value found in the Sequence Number is less than the | |
3467 | * ('Peer- Sequence-Number' + 1), simply skip to the next | |
3468 | * ASCONF, and include in the outbound response packet | |
3469 | * any previously cached ASCONF-ACK response that was | |
3470 | * sent and saved that matches the Sequence Number of the | |
3471 | * ASCONF. Note: It is possible that no cached ASCONF-ACK | |
3472 | * Chunk exists. This will occur when an older ASCONF | |
3473 | * arrives out of order. In such a case, the receiver | |
3474 | * should skip the ASCONF Chunk and not include ASCONF-ACK | |
3475 | * Chunk for that chunk. | |
1da177e4 | 3476 | */ |
a08de64d VY |
3477 | asconf_ack = sctp_assoc_lookup_asconf_ack(asoc, hdr->serial); |
3478 | if (!asconf_ack) | |
1da177e4 LT |
3479 | return SCTP_DISPOSITION_DISCARD; |
3480 | } else { | |
a08de64d | 3481 | /* ADDIP 5.2 E5) Otherwise, the ASCONF Chunk is discarded since |
1da177e4 | 3482 | * it must be either a stale packet or from an attacker. |
d808ad9a | 3483 | */ |
1da177e4 LT |
3484 | return SCTP_DISPOSITION_DISCARD; |
3485 | } | |
3486 | ||
a08de64d VY |
3487 | /* ADDIP 5.2 E6) The destination address of the SCTP packet |
3488 | * containing the ASCONF-ACK Chunks MUST be the source address of | |
3489 | * the SCTP packet that held the ASCONF Chunks. | |
3490 | * | |
3491 | * To do this properly, we'll set the destination address of the chunk | |
3492 | * and at the transmit time, will try look up the transport to use. | |
3493 | * Since ASCONFs may be bundled, the correct transport may not be | |
3494 | * created untill we process the entire packet, thus this workaround. | |
1da177e4 | 3495 | */ |
a08de64d | 3496 | asconf_ack->dest = chunk->source; |
1da177e4 | 3497 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack)); |
d808ad9a | 3498 | |
1da177e4 LT |
3499 | return SCTP_DISPOSITION_CONSUME; |
3500 | } | |
3501 | ||
3502 | /* | |
3503 | * ADDIP Section 4.3 General rules for address manipulation | |
3504 | * When building TLV parameters for the ASCONF Chunk that will add or | |
3505 | * delete IP addresses the D0 to D13 rules should be applied: | |
3506 | */ | |
3507 | sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, | |
3508 | const struct sctp_association *asoc, | |
d808ad9a | 3509 | const sctp_subtype_t type, void *arg, |
1da177e4 LT |
3510 | sctp_cmd_seq_t *commands) |
3511 | { | |
3512 | struct sctp_chunk *asconf_ack = arg; | |
3513 | struct sctp_chunk *last_asconf = asoc->addip_last_asconf; | |
3514 | struct sctp_chunk *abort; | |
6f4c618d | 3515 | struct sctp_paramhdr *err_param = NULL; |
1da177e4 LT |
3516 | sctp_addiphdr_t *addip_hdr; |
3517 | __u32 sent_serial, rcvd_serial; | |
3518 | ||
3519 | if (!sctp_vtag_verify(asconf_ack, asoc)) { | |
3520 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3521 | SCTP_NULL()); | |
3522 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3523 | } | |
3524 | ||
6afd2e83 VY |
3525 | /* ADD-IP, Section 4.1.2: |
3526 | * This chunk MUST be sent in an authenticated way by using | |
3527 | * the mechanism defined in [I-D.ietf-tsvwg-sctp-auth]. If this chunk | |
3528 | * is received unauthenticated it MUST be silently discarded as | |
3529 | * described in [I-D.ietf-tsvwg-sctp-auth]. | |
3530 | */ | |
3531 | if (!sctp_addip_noauth && !asconf_ack->auth) | |
3532 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
3533 | ||
1da177e4 LT |
3534 | /* Make sure that the ADDIP chunk has a valid length. */ |
3535 | if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t))) | |
3536 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3537 | commands); | |
3538 | ||
3539 | addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data; | |
3540 | rcvd_serial = ntohl(addip_hdr->serial); | |
3541 | ||
6f4c618d WY |
3542 | /* Verify the ASCONF-ACK chunk before processing it. */ |
3543 | if (!sctp_verify_asconf(asoc, | |
3544 | (sctp_paramhdr_t *)addip_hdr->params, | |
3545 | (void *)asconf_ack->chunk_end, | |
3546 | &err_param)) | |
ba016670 WY |
3547 | return sctp_sf_violation_paramlen(ep, asoc, type, arg, |
3548 | (void *)err_param, commands); | |
6f4c618d | 3549 | |
1da177e4 LT |
3550 | if (last_asconf) { |
3551 | addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr; | |
3552 | sent_serial = ntohl(addip_hdr->serial); | |
3553 | } else { | |
3554 | sent_serial = asoc->addip_serial - 1; | |
3555 | } | |
3556 | ||
3557 | /* D0) If an endpoint receives an ASCONF-ACK that is greater than or | |
3558 | * equal to the next serial number to be used but no ASCONF chunk is | |
3559 | * outstanding the endpoint MUST ABORT the association. Note that a | |
3560 | * sequence number is greater than if it is no more than 2^^31-1 | |
3561 | * larger than the current sequence number (using serial arithmetic). | |
3562 | */ | |
3563 | if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) && | |
3564 | !(asoc->addip_last_asconf)) { | |
3565 | abort = sctp_make_abort(asoc, asconf_ack, | |
3566 | sizeof(sctp_errhdr_t)); | |
3567 | if (abort) { | |
00f1c2df | 3568 | sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0); |
1da177e4 LT |
3569 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3570 | SCTP_CHUNK(abort)); | |
3571 | } | |
3572 | /* We are going to ABORT, so we might as well stop | |
3573 | * processing the rest of the chunks in the packet. | |
3574 | */ | |
3575 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3576 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3577 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3578 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3579 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3580 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3581 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3582 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3583 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3584 | return SCTP_DISPOSITION_ABORT; | |
3585 | } | |
3586 | ||
3587 | if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) { | |
3588 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3589 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3590 | ||
3591 | if (!sctp_process_asconf_ack((struct sctp_association *)asoc, | |
3592 | asconf_ack)) | |
3593 | return SCTP_DISPOSITION_CONSUME; | |
3594 | ||
3595 | abort = sctp_make_abort(asoc, asconf_ack, | |
3596 | sizeof(sctp_errhdr_t)); | |
3597 | if (abort) { | |
00f1c2df | 3598 | sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0); |
1da177e4 LT |
3599 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3600 | SCTP_CHUNK(abort)); | |
3601 | } | |
3602 | /* We are going to ABORT, so we might as well stop | |
3603 | * processing the rest of the chunks in the packet. | |
3604 | */ | |
3605 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3606 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3607 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3608 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3609 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3610 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3611 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3612 | return SCTP_DISPOSITION_ABORT; | |
3613 | } | |
3614 | ||
3615 | return SCTP_DISPOSITION_DISCARD; | |
3616 | } | |
3617 | ||
3618 | /* | |
3619 | * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP | |
3620 | * | |
3621 | * When a FORWARD TSN chunk arrives, the data receiver MUST first update | |
3622 | * its cumulative TSN point to the value carried in the FORWARD TSN | |
3623 | * chunk, and then MUST further advance its cumulative TSN point locally | |
3624 | * if possible. | |
3625 | * After the above processing, the data receiver MUST stop reporting any | |
3626 | * missing TSNs earlier than or equal to the new cumulative TSN point. | |
3627 | * | |
3628 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3629 | * | |
3630 | * The return value is the disposition of the chunk. | |
3631 | */ | |
3632 | sctp_disposition_t sctp_sf_eat_fwd_tsn(const struct sctp_endpoint *ep, | |
3633 | const struct sctp_association *asoc, | |
3634 | const sctp_subtype_t type, | |
3635 | void *arg, | |
3636 | sctp_cmd_seq_t *commands) | |
3637 | { | |
3638 | struct sctp_chunk *chunk = arg; | |
3639 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
3640 | __u16 len; | |
3641 | __u32 tsn; | |
3642 | ||
3643 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3644 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3645 | SCTP_NULL()); | |
3646 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3647 | } | |
3648 | ||
3649 | /* Make sure that the FORWARD_TSN chunk has valid length. */ | |
3650 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3651 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3652 | commands); | |
3653 | ||
3654 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3655 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3656 | len = ntohs(chunk->chunk_hdr->length); | |
3657 | len -= sizeof(struct sctp_chunkhdr); | |
3658 | skb_pull(chunk->skb, len); | |
3659 | ||
3660 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
0dc47877 | 3661 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __func__, tsn); |
1da177e4 LT |
3662 | |
3663 | /* The TSN is too high--silently discard the chunk and count on it | |
3664 | * getting retransmitted later. | |
3665 | */ | |
3666 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3667 | goto discard_noforce; | |
3668 | ||
3669 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); | |
3670 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3671 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3672 | SCTP_CHUNK(chunk)); |
d808ad9a | 3673 | |
1da177e4 LT |
3674 | /* Count this as receiving DATA. */ |
3675 | if (asoc->autoclose) { | |
3676 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3677 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
3678 | } | |
d808ad9a | 3679 | |
1da177e4 | 3680 | /* FIXME: For now send a SACK, but DATA processing may |
d808ad9a | 3681 | * send another. |
1da177e4 LT |
3682 | */ |
3683 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); | |
1da177e4 LT |
3684 | |
3685 | return SCTP_DISPOSITION_CONSUME; | |
3686 | ||
3687 | discard_noforce: | |
3688 | return SCTP_DISPOSITION_DISCARD; | |
3689 | } | |
3690 | ||
3691 | sctp_disposition_t sctp_sf_eat_fwd_tsn_fast( | |
3692 | const struct sctp_endpoint *ep, | |
3693 | const struct sctp_association *asoc, | |
3694 | const sctp_subtype_t type, | |
3695 | void *arg, | |
3696 | sctp_cmd_seq_t *commands) | |
3697 | { | |
3698 | struct sctp_chunk *chunk = arg; | |
3699 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
3700 | __u16 len; | |
3701 | __u32 tsn; | |
3702 | ||
3703 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3704 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3705 | SCTP_NULL()); | |
3706 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3707 | } | |
3708 | ||
3709 | /* Make sure that the FORWARD_TSN chunk has a valid length. */ | |
3710 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3711 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3712 | commands); | |
3713 | ||
3714 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3715 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3716 | len = ntohs(chunk->chunk_hdr->length); | |
3717 | len -= sizeof(struct sctp_chunkhdr); | |
3718 | skb_pull(chunk->skb, len); | |
3719 | ||
3720 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
0dc47877 | 3721 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __func__, tsn); |
1da177e4 LT |
3722 | |
3723 | /* The TSN is too high--silently discard the chunk and count on it | |
3724 | * getting retransmitted later. | |
3725 | */ | |
3726 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3727 | goto gen_shutdown; | |
3728 | ||
3729 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); | |
3730 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3731 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3732 | SCTP_CHUNK(chunk)); |
d808ad9a | 3733 | |
1da177e4 LT |
3734 | /* Go a head and force a SACK, since we are shutting down. */ |
3735 | gen_shutdown: | |
3736 | /* Implementor's Guide. | |
3737 | * | |
3738 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3739 | * respond to each received packet containing one or more DATA chunk(s) | |
3740 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3741 | */ | |
3742 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3743 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3744 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3745 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3746 | ||
d808ad9a | 3747 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3748 | } |
3749 | ||
bbd0d598 VY |
3750 | /* |
3751 | * SCTP-AUTH Section 6.3 Receving authenticated chukns | |
3752 | * | |
3753 | * The receiver MUST use the HMAC algorithm indicated in the HMAC | |
3754 | * Identifier field. If this algorithm was not specified by the | |
3755 | * receiver in the HMAC-ALGO parameter in the INIT or INIT-ACK chunk | |
3756 | * during association setup, the AUTH chunk and all chunks after it MUST | |
3757 | * be discarded and an ERROR chunk SHOULD be sent with the error cause | |
3758 | * defined in Section 4.1. | |
3759 | * | |
3760 | * If an endpoint with no shared key receives a Shared Key Identifier | |
3761 | * other than 0, it MUST silently discard all authenticated chunks. If | |
3762 | * the endpoint has at least one endpoint pair shared key for the peer, | |
3763 | * it MUST use the key specified by the Shared Key Identifier if a | |
3764 | * key has been configured for that Shared Key Identifier. If no | |
3765 | * endpoint pair shared key has been configured for that Shared Key | |
3766 | * Identifier, all authenticated chunks MUST be silently discarded. | |
3767 | * | |
3768 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3769 | * | |
3770 | * The return value is the disposition of the chunk. | |
3771 | */ | |
3772 | static sctp_ierror_t sctp_sf_authenticate(const struct sctp_endpoint *ep, | |
3773 | const struct sctp_association *asoc, | |
3774 | const sctp_subtype_t type, | |
3775 | struct sctp_chunk *chunk) | |
3776 | { | |
3777 | struct sctp_authhdr *auth_hdr; | |
3778 | struct sctp_hmac *hmac; | |
3779 | unsigned int sig_len; | |
3780 | __u16 key_id; | |
3781 | __u8 *save_digest; | |
3782 | __u8 *digest; | |
3783 | ||
3784 | /* Pull in the auth header, so we can do some more verification */ | |
3785 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
3786 | chunk->subh.auth_hdr = auth_hdr; | |
3787 | skb_pull(chunk->skb, sizeof(struct sctp_authhdr)); | |
3788 | ||
3789 | /* Make sure that we suport the HMAC algorithm from the auth | |
3790 | * chunk. | |
3791 | */ | |
3792 | if (!sctp_auth_asoc_verify_hmac_id(asoc, auth_hdr->hmac_id)) | |
3793 | return SCTP_IERROR_AUTH_BAD_HMAC; | |
3794 | ||
3795 | /* Make sure that the provided shared key identifier has been | |
3796 | * configured | |
3797 | */ | |
3798 | key_id = ntohs(auth_hdr->shkey_id); | |
3799 | if (key_id != asoc->active_key_id && !sctp_auth_get_shkey(asoc, key_id)) | |
3800 | return SCTP_IERROR_AUTH_BAD_KEYID; | |
3801 | ||
3802 | ||
3803 | /* Make sure that the length of the signature matches what | |
3804 | * we expect. | |
3805 | */ | |
3806 | sig_len = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_auth_chunk_t); | |
3807 | hmac = sctp_auth_get_hmac(ntohs(auth_hdr->hmac_id)); | |
3808 | if (sig_len != hmac->hmac_len) | |
3809 | return SCTP_IERROR_PROTO_VIOLATION; | |
3810 | ||
3811 | /* Now that we've done validation checks, we can compute and | |
3812 | * verify the hmac. The steps involved are: | |
3813 | * 1. Save the digest from the chunk. | |
3814 | * 2. Zero out the digest in the chunk. | |
3815 | * 3. Compute the new digest | |
3816 | * 4. Compare saved and new digests. | |
3817 | */ | |
3818 | digest = auth_hdr->hmac; | |
3819 | skb_pull(chunk->skb, sig_len); | |
3820 | ||
3821 | save_digest = kmemdup(digest, sig_len, GFP_ATOMIC); | |
3822 | if (!save_digest) | |
3823 | goto nomem; | |
3824 | ||
3825 | memset(digest, 0, sig_len); | |
3826 | ||
3827 | sctp_auth_calculate_hmac(asoc, chunk->skb, | |
3828 | (struct sctp_auth_chunk *)chunk->chunk_hdr, | |
3829 | GFP_ATOMIC); | |
3830 | ||
3831 | /* Discard the packet if the digests do not match */ | |
3832 | if (memcmp(save_digest, digest, sig_len)) { | |
3833 | kfree(save_digest); | |
3834 | return SCTP_IERROR_BAD_SIG; | |
3835 | } | |
3836 | ||
3837 | kfree(save_digest); | |
3838 | chunk->auth = 1; | |
3839 | ||
3840 | return SCTP_IERROR_NO_ERROR; | |
3841 | nomem: | |
3842 | return SCTP_IERROR_NOMEM; | |
3843 | } | |
3844 | ||
3845 | sctp_disposition_t sctp_sf_eat_auth(const struct sctp_endpoint *ep, | |
3846 | const struct sctp_association *asoc, | |
3847 | const sctp_subtype_t type, | |
3848 | void *arg, | |
3849 | sctp_cmd_seq_t *commands) | |
3850 | { | |
3851 | struct sctp_authhdr *auth_hdr; | |
3852 | struct sctp_chunk *chunk = arg; | |
3853 | struct sctp_chunk *err_chunk; | |
3854 | sctp_ierror_t error; | |
3855 | ||
d2f19fa1 WY |
3856 | /* Make sure that the peer has AUTH capable */ |
3857 | if (!asoc->peer.auth_capable) | |
3858 | return sctp_sf_unk_chunk(ep, asoc, type, arg, commands); | |
3859 | ||
bbd0d598 VY |
3860 | if (!sctp_vtag_verify(chunk, asoc)) { |
3861 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3862 | SCTP_NULL()); | |
3863 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3864 | } | |
3865 | ||
3866 | /* Make sure that the AUTH chunk has valid length. */ | |
3867 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_auth_chunk))) | |
3868 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3869 | commands); | |
3870 | ||
3871 | auth_hdr = (struct sctp_authhdr *)chunk->skb->data; | |
3872 | error = sctp_sf_authenticate(ep, asoc, type, chunk); | |
3873 | switch (error) { | |
3874 | case SCTP_IERROR_AUTH_BAD_HMAC: | |
3875 | /* Generate the ERROR chunk and discard the rest | |
3876 | * of the packet | |
3877 | */ | |
3878 | err_chunk = sctp_make_op_error(asoc, chunk, | |
3879 | SCTP_ERROR_UNSUP_HMAC, | |
3880 | &auth_hdr->hmac_id, | |
3881 | sizeof(__u16)); | |
3882 | if (err_chunk) { | |
3883 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3884 | SCTP_CHUNK(err_chunk)); | |
3885 | } | |
3886 | /* Fall Through */ | |
3887 | case SCTP_IERROR_AUTH_BAD_KEYID: | |
3888 | case SCTP_IERROR_BAD_SIG: | |
3889 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3890 | break; | |
3891 | case SCTP_IERROR_PROTO_VIOLATION: | |
3892 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3893 | commands); | |
3894 | break; | |
3895 | case SCTP_IERROR_NOMEM: | |
3896 | return SCTP_DISPOSITION_NOMEM; | |
3897 | default: | |
3898 | break; | |
3899 | } | |
3900 | ||
65b07e5d VY |
3901 | if (asoc->active_key_id != ntohs(auth_hdr->shkey_id)) { |
3902 | struct sctp_ulpevent *ev; | |
3903 | ||
3904 | ev = sctp_ulpevent_make_authkey(asoc, ntohs(auth_hdr->shkey_id), | |
3905 | SCTP_AUTH_NEWKEY, GFP_ATOMIC); | |
3906 | ||
3907 | if (!ev) | |
3908 | return -ENOMEM; | |
3909 | ||
3910 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
3911 | SCTP_ULPEVENT(ev)); | |
3912 | } | |
3913 | ||
bbd0d598 VY |
3914 | return SCTP_DISPOSITION_CONSUME; |
3915 | } | |
3916 | ||
1da177e4 LT |
3917 | /* |
3918 | * Process an unknown chunk. | |
3919 | * | |
3920 | * Section: 3.2. Also, 2.1 in the implementor's guide. | |
3921 | * | |
3922 | * Chunk Types are encoded such that the highest-order two bits specify | |
3923 | * the action that must be taken if the processing endpoint does not | |
3924 | * recognize the Chunk Type. | |
3925 | * | |
3926 | * 00 - Stop processing this SCTP packet and discard it, do not process | |
3927 | * any further chunks within it. | |
3928 | * | |
3929 | * 01 - Stop processing this SCTP packet and discard it, do not process | |
3930 | * any further chunks within it, and report the unrecognized | |
3931 | * chunk in an 'Unrecognized Chunk Type'. | |
3932 | * | |
3933 | * 10 - Skip this chunk and continue processing. | |
3934 | * | |
3935 | * 11 - Skip this chunk and continue processing, but report in an ERROR | |
3936 | * Chunk using the 'Unrecognized Chunk Type' cause of error. | |
3937 | * | |
3938 | * The return value is the disposition of the chunk. | |
3939 | */ | |
3940 | sctp_disposition_t sctp_sf_unk_chunk(const struct sctp_endpoint *ep, | |
3941 | const struct sctp_association *asoc, | |
3942 | const sctp_subtype_t type, | |
3943 | void *arg, | |
3944 | sctp_cmd_seq_t *commands) | |
3945 | { | |
3946 | struct sctp_chunk *unk_chunk = arg; | |
3947 | struct sctp_chunk *err_chunk; | |
3948 | sctp_chunkhdr_t *hdr; | |
3949 | ||
3950 | SCTP_DEBUG_PRINTK("Processing the unknown chunk id %d.\n", type.chunk); | |
3951 | ||
3952 | if (!sctp_vtag_verify(unk_chunk, asoc)) | |
3953 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3954 | ||
3955 | /* Make sure that the chunk has a valid length. | |
3956 | * Since we don't know the chunk type, we use a general | |
3957 | * chunkhdr structure to make a comparison. | |
3958 | */ | |
3959 | if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t))) | |
3960 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3961 | commands); | |
3962 | ||
3963 | switch (type.chunk & SCTP_CID_ACTION_MASK) { | |
3964 | case SCTP_CID_ACTION_DISCARD: | |
3965 | /* Discard the packet. */ | |
3966 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3967 | break; | |
3968 | case SCTP_CID_ACTION_DISCARD_ERR: | |
1da177e4 LT |
3969 | /* Generate an ERROR chunk as response. */ |
3970 | hdr = unk_chunk->chunk_hdr; | |
3971 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
3972 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
3973 | WORD_ROUND(ntohs(hdr->length))); | |
3974 | if (err_chunk) { | |
3975 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3976 | SCTP_CHUNK(err_chunk)); | |
3977 | } | |
2e3216cd VY |
3978 | |
3979 | /* Discard the packet. */ | |
3980 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1da177e4 LT |
3981 | return SCTP_DISPOSITION_CONSUME; |
3982 | break; | |
3983 | case SCTP_CID_ACTION_SKIP: | |
3984 | /* Skip the chunk. */ | |
3985 | return SCTP_DISPOSITION_DISCARD; | |
3986 | break; | |
3987 | case SCTP_CID_ACTION_SKIP_ERR: | |
3988 | /* Generate an ERROR chunk as response. */ | |
3989 | hdr = unk_chunk->chunk_hdr; | |
3990 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
3991 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
3992 | WORD_ROUND(ntohs(hdr->length))); | |
3993 | if (err_chunk) { | |
3994 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3995 | SCTP_CHUNK(err_chunk)); | |
3996 | } | |
3997 | /* Skip the chunk. */ | |
3998 | return SCTP_DISPOSITION_CONSUME; | |
3999 | break; | |
4000 | default: | |
4001 | break; | |
4002 | } | |
4003 | ||
4004 | return SCTP_DISPOSITION_DISCARD; | |
4005 | } | |
4006 | ||
4007 | /* | |
4008 | * Discard the chunk. | |
4009 | * | |
4010 | * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2 | |
4011 | * [Too numerous to mention...] | |
4012 | * Verification Tag: No verification needed. | |
4013 | * Inputs | |
4014 | * (endpoint, asoc, chunk) | |
4015 | * | |
4016 | * Outputs | |
4017 | * (asoc, reply_msg, msg_up, timers, counters) | |
4018 | * | |
4019 | * The return value is the disposition of the chunk. | |
4020 | */ | |
4021 | sctp_disposition_t sctp_sf_discard_chunk(const struct sctp_endpoint *ep, | |
4022 | const struct sctp_association *asoc, | |
4023 | const sctp_subtype_t type, | |
4024 | void *arg, | |
4025 | sctp_cmd_seq_t *commands) | |
4026 | { | |
ece25dfa VY |
4027 | struct sctp_chunk *chunk = arg; |
4028 | ||
4029 | /* Make sure that the chunk has a valid length. | |
4030 | * Since we don't know the chunk type, we use a general | |
4031 | * chunkhdr structure to make a comparison. | |
4032 | */ | |
4033 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
4034 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4035 | commands); | |
4036 | ||
1da177e4 LT |
4037 | SCTP_DEBUG_PRINTK("Chunk %d is discarded\n", type.chunk); |
4038 | return SCTP_DISPOSITION_DISCARD; | |
4039 | } | |
4040 | ||
4041 | /* | |
4042 | * Discard the whole packet. | |
4043 | * | |
4044 | * Section: 8.4 2) | |
4045 | * | |
4046 | * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST | |
4047 | * silently discard the OOTB packet and take no further action. | |
1da177e4 LT |
4048 | * |
4049 | * Verification Tag: No verification necessary | |
4050 | * | |
4051 | * Inputs | |
4052 | * (endpoint, asoc, chunk) | |
4053 | * | |
4054 | * Outputs | |
4055 | * (asoc, reply_msg, msg_up, timers, counters) | |
4056 | * | |
4057 | * The return value is the disposition of the chunk. | |
4058 | */ | |
4059 | sctp_disposition_t sctp_sf_pdiscard(const struct sctp_endpoint *ep, | |
4060 | const struct sctp_association *asoc, | |
4061 | const sctp_subtype_t type, | |
4062 | void *arg, | |
4063 | sctp_cmd_seq_t *commands) | |
4064 | { | |
ac0b0462 | 4065 | SCTP_INC_STATS(SCTP_MIB_IN_PKT_DISCARDS); |
1da177e4 LT |
4066 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
4067 | ||
4068 | return SCTP_DISPOSITION_CONSUME; | |
4069 | } | |
4070 | ||
4071 | ||
4072 | /* | |
4073 | * The other end is violating protocol. | |
4074 | * | |
4075 | * Section: Not specified | |
4076 | * Verification Tag: Not specified | |
4077 | * Inputs | |
4078 | * (endpoint, asoc, chunk) | |
4079 | * | |
4080 | * Outputs | |
4081 | * (asoc, reply_msg, msg_up, timers, counters) | |
4082 | * | |
4083 | * We simply tag the chunk as a violation. The state machine will log | |
4084 | * the violation and continue. | |
4085 | */ | |
4086 | sctp_disposition_t sctp_sf_violation(const struct sctp_endpoint *ep, | |
4087 | const struct sctp_association *asoc, | |
4088 | const sctp_subtype_t type, | |
4089 | void *arg, | |
4090 | sctp_cmd_seq_t *commands) | |
4091 | { | |
ece25dfa VY |
4092 | struct sctp_chunk *chunk = arg; |
4093 | ||
4094 | /* Make sure that the chunk has a valid length. */ | |
4095 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
4096 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4097 | commands); | |
4098 | ||
1da177e4 LT |
4099 | return SCTP_DISPOSITION_VIOLATION; |
4100 | } | |
4101 | ||
1da177e4 | 4102 | /* |
aecedeab | 4103 | * Common function to handle a protocol violation. |
1da177e4 | 4104 | */ |
aecedeab | 4105 | static sctp_disposition_t sctp_sf_abort_violation( |
ece25dfa | 4106 | const struct sctp_endpoint *ep, |
1da177e4 | 4107 | const struct sctp_association *asoc, |
1da177e4 | 4108 | void *arg, |
aecedeab WY |
4109 | sctp_cmd_seq_t *commands, |
4110 | const __u8 *payload, | |
4111 | const size_t paylen) | |
1da177e4 | 4112 | { |
ece25dfa | 4113 | struct sctp_packet *packet = NULL; |
1da177e4 LT |
4114 | struct sctp_chunk *chunk = arg; |
4115 | struct sctp_chunk *abort = NULL; | |
1da177e4 | 4116 | |
bbd0d598 VY |
4117 | /* SCTP-AUTH, Section 6.3: |
4118 | * It should be noted that if the receiver wants to tear | |
4119 | * down an association in an authenticated way only, the | |
4120 | * handling of malformed packets should not result in | |
4121 | * tearing down the association. | |
4122 | * | |
4123 | * This means that if we only want to abort associations | |
4124 | * in an authenticated way (i.e AUTH+ABORT), then we | |
ac461a03 | 4125 | * can't destroy this association just becuase the packet |
bbd0d598 VY |
4126 | * was malformed. |
4127 | */ | |
4128 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) | |
4129 | goto discard; | |
4130 | ||
9abed245 JJ |
4131 | /* Make the abort chunk. */ |
4132 | abort = sctp_make_abort_violation(asoc, chunk, payload, paylen); | |
4133 | if (!abort) | |
4134 | goto nomem; | |
4135 | ||
ece25dfa | 4136 | if (asoc) { |
f4ad85ca GJ |
4137 | /* Treat INIT-ACK as a special case during COOKIE-WAIT. */ |
4138 | if (chunk->chunk_hdr->type == SCTP_CID_INIT_ACK && | |
4139 | !asoc->peer.i.init_tag) { | |
4140 | sctp_initack_chunk_t *initack; | |
4141 | ||
4142 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
4143 | if (!sctp_chunk_length_valid(chunk, | |
4144 | sizeof(sctp_initack_chunk_t))) | |
4145 | abort->chunk_hdr->flags |= SCTP_CHUNK_FLAG_T; | |
4146 | else { | |
4147 | unsigned int inittag; | |
4148 | ||
4149 | inittag = ntohl(initack->init_hdr.init_tag); | |
4150 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_INITTAG, | |
4151 | SCTP_U32(inittag)); | |
4152 | } | |
4153 | } | |
4154 | ||
ece25dfa VY |
4155 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
4156 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 | 4157 | |
ece25dfa VY |
4158 | if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { |
4159 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4160 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4161 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4162 | SCTP_ERROR(ECONNREFUSED)); | |
4163 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
4164 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4165 | } else { | |
4166 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4167 | SCTP_ERROR(ECONNABORTED)); | |
4168 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4169 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4170 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4171 | } | |
1da177e4 | 4172 | } else { |
ece25dfa VY |
4173 | packet = sctp_ootb_pkt_new(asoc, chunk); |
4174 | ||
4175 | if (!packet) | |
4176 | goto nomem_pkt; | |
4177 | ||
4178 | if (sctp_test_T_bit(abort)) | |
4179 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
4180 | ||
4181 | abort->skb->sk = ep->base.sk; | |
4182 | ||
4183 | sctp_packet_append_chunk(packet, abort); | |
4184 | ||
4185 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
4186 | SCTP_PACKET(packet)); | |
4187 | ||
4188 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 LT |
4189 | } |
4190 | ||
bbd0d598 | 4191 | discard: |
ece25dfa | 4192 | sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
1da177e4 LT |
4193 | |
4194 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
d808ad9a | 4195 | |
1da177e4 LT |
4196 | return SCTP_DISPOSITION_ABORT; |
4197 | ||
ece25dfa VY |
4198 | nomem_pkt: |
4199 | sctp_chunk_free(abort); | |
1da177e4 LT |
4200 | nomem: |
4201 | return SCTP_DISPOSITION_NOMEM; | |
4202 | } | |
4203 | ||
aecedeab WY |
4204 | /* |
4205 | * Handle a protocol violation when the chunk length is invalid. | |
4206 | * "Invalid" length is identified as smaller then the minimal length a | |
4207 | * given chunk can be. For example, a SACK chunk has invalid length | |
4208 | * if it's length is set to be smaller then the size of sctp_sack_chunk_t. | |
4209 | * | |
4210 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4211 | * error code. | |
4212 | * | |
4213 | * Section: Not specified | |
4214 | * Verification Tag: Nothing to do | |
4215 | * Inputs | |
4216 | * (endpoint, asoc, chunk) | |
4217 | * | |
4218 | * Outputs | |
4219 | * (reply_msg, msg_up, counters) | |
4220 | * | |
4221 | * Generate an ABORT chunk and terminate the association. | |
4222 | */ | |
4223 | static sctp_disposition_t sctp_sf_violation_chunklen( | |
4224 | const struct sctp_endpoint *ep, | |
4225 | const struct sctp_association *asoc, | |
4226 | const sctp_subtype_t type, | |
4227 | void *arg, | |
4228 | sctp_cmd_seq_t *commands) | |
4229 | { | |
2444844c | 4230 | static const char err_str[]="The following chunk had invalid length:"; |
aecedeab | 4231 | |
ece25dfa | 4232 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
4233 | sizeof(err_str)); |
4234 | } | |
4235 | ||
6f4c618d WY |
4236 | /* |
4237 | * Handle a protocol violation when the parameter length is invalid. | |
4238 | * "Invalid" length is identified as smaller then the minimal length a | |
4239 | * given parameter can be. | |
4240 | */ | |
4241 | static sctp_disposition_t sctp_sf_violation_paramlen( | |
4242 | const struct sctp_endpoint *ep, | |
4243 | const struct sctp_association *asoc, | |
4244 | const sctp_subtype_t type, | |
ba016670 WY |
4245 | void *arg, void *ext, |
4246 | sctp_cmd_seq_t *commands) | |
4247 | { | |
4248 | struct sctp_chunk *chunk = arg; | |
4249 | struct sctp_paramhdr *param = ext; | |
4250 | struct sctp_chunk *abort = NULL; | |
6f4c618d | 4251 | |
ba016670 WY |
4252 | if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) |
4253 | goto discard; | |
4254 | ||
4255 | /* Make the abort chunk. */ | |
4256 | abort = sctp_make_violation_paramlen(asoc, chunk, param); | |
4257 | if (!abort) | |
4258 | goto nomem; | |
4259 | ||
4260 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
4261 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
4262 | ||
4263 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
4264 | SCTP_ERROR(ECONNABORTED)); | |
4265 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
4266 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
4267 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4268 | ||
4269 | discard: | |
4270 | sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); | |
4271 | ||
4272 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4273 | ||
4274 | return SCTP_DISPOSITION_ABORT; | |
4275 | nomem: | |
4276 | return SCTP_DISPOSITION_NOMEM; | |
6f4c618d WY |
4277 | } |
4278 | ||
aecedeab WY |
4279 | /* Handle a protocol violation when the peer trying to advance the |
4280 | * cumulative tsn ack to a point beyond the max tsn currently sent. | |
4281 | * | |
4282 | * We inform the other end by sending an ABORT with a Protocol Violation | |
4283 | * error code. | |
4284 | */ | |
4285 | static sctp_disposition_t sctp_sf_violation_ctsn( | |
4286 | const struct sctp_endpoint *ep, | |
4287 | const struct sctp_association *asoc, | |
4288 | const sctp_subtype_t type, | |
4289 | void *arg, | |
4290 | sctp_cmd_seq_t *commands) | |
4291 | { | |
2444844c | 4292 | static const char err_str[]="The cumulative tsn ack beyond the max tsn currently sent:"; |
aecedeab | 4293 | |
ece25dfa | 4294 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
4295 | sizeof(err_str)); |
4296 | } | |
4297 | ||
ece25dfa VY |
4298 | /* Handle protocol violation of an invalid chunk bundling. For example, |
4299 | * when we have an association and we recieve bundled INIT-ACK, or | |
4300 | * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle" | |
4301 | * statement from the specs. Additinally, there might be an attacker | |
4302 | * on the path and we may not want to continue this communication. | |
4303 | */ | |
4304 | static sctp_disposition_t sctp_sf_violation_chunk( | |
4305 | const struct sctp_endpoint *ep, | |
4306 | const struct sctp_association *asoc, | |
4307 | const sctp_subtype_t type, | |
4308 | void *arg, | |
4309 | sctp_cmd_seq_t *commands) | |
4310 | { | |
2444844c | 4311 | static const char err_str[]="The following chunk violates protocol:"; |
ece25dfa VY |
4312 | |
4313 | if (!asoc) | |
4314 | return sctp_sf_violation(ep, asoc, type, arg, commands); | |
4315 | ||
4316 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, | |
4317 | sizeof(err_str)); | |
4318 | } | |
1da177e4 LT |
4319 | /*************************************************************************** |
4320 | * These are the state functions for handling primitive (Section 10) events. | |
4321 | ***************************************************************************/ | |
4322 | /* | |
4323 | * sctp_sf_do_prm_asoc | |
4324 | * | |
4325 | * Section: 10.1 ULP-to-SCTP | |
4326 | * B) Associate | |
4327 | * | |
4328 | * Format: ASSOCIATE(local SCTP instance name, destination transport addr, | |
4329 | * outbound stream count) | |
4330 | * -> association id [,destination transport addr list] [,outbound stream | |
4331 | * count] | |
4332 | * | |
4333 | * This primitive allows the upper layer to initiate an association to a | |
4334 | * specific peer endpoint. | |
4335 | * | |
4336 | * The peer endpoint shall be specified by one of the transport addresses | |
4337 | * which defines the endpoint (see Section 1.4). If the local SCTP | |
4338 | * instance has not been initialized, the ASSOCIATE is considered an | |
4339 | * error. | |
4340 | * [This is not relevant for the kernel implementation since we do all | |
4341 | * initialization at boot time. It we hadn't initialized we wouldn't | |
4342 | * get anywhere near this code.] | |
4343 | * | |
4344 | * An association id, which is a local handle to the SCTP association, | |
4345 | * will be returned on successful establishment of the association. If | |
4346 | * SCTP is not able to open an SCTP association with the peer endpoint, | |
4347 | * an error is returned. | |
4348 | * [In the kernel implementation, the struct sctp_association needs to | |
4349 | * be created BEFORE causing this primitive to run.] | |
4350 | * | |
4351 | * Other association parameters may be returned, including the | |
4352 | * complete destination transport addresses of the peer as well as the | |
4353 | * outbound stream count of the local endpoint. One of the transport | |
4354 | * address from the returned destination addresses will be selected by | |
4355 | * the local endpoint as default primary path for sending SCTP packets | |
4356 | * to this peer. The returned "destination transport addr list" can | |
4357 | * be used by the ULP to change the default primary path or to force | |
4358 | * sending a packet to a specific transport address. [All of this | |
4359 | * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING | |
4360 | * function.] | |
4361 | * | |
4362 | * Mandatory attributes: | |
4363 | * | |
4364 | * o local SCTP instance name - obtained from the INITIALIZE operation. | |
4365 | * [This is the argument asoc.] | |
4366 | * o destination transport addr - specified as one of the transport | |
4367 | * addresses of the peer endpoint with which the association is to be | |
4368 | * established. | |
4369 | * [This is asoc->peer.active_path.] | |
4370 | * o outbound stream count - the number of outbound streams the ULP | |
4371 | * would like to open towards this peer endpoint. | |
4372 | * [BUG: This is not currently implemented.] | |
4373 | * Optional attributes: | |
4374 | * | |
4375 | * None. | |
4376 | * | |
4377 | * The return value is a disposition. | |
4378 | */ | |
4379 | sctp_disposition_t sctp_sf_do_prm_asoc(const struct sctp_endpoint *ep, | |
4380 | const struct sctp_association *asoc, | |
4381 | const sctp_subtype_t type, | |
4382 | void *arg, | |
4383 | sctp_cmd_seq_t *commands) | |
4384 | { | |
4385 | struct sctp_chunk *repl; | |
ab38fb04 | 4386 | struct sctp_association* my_asoc; |
1da177e4 LT |
4387 | |
4388 | /* The comment below says that we enter COOKIE-WAIT AFTER | |
4389 | * sending the INIT, but that doesn't actually work in our | |
4390 | * implementation... | |
4391 | */ | |
4392 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4393 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
4394 | ||
4395 | /* RFC 2960 5.1 Normal Establishment of an Association | |
4396 | * | |
4397 | * A) "A" first sends an INIT chunk to "Z". In the INIT, "A" | |
4398 | * must provide its Verification Tag (Tag_A) in the Initiate | |
4399 | * Tag field. Tag_A SHOULD be a random number in the range of | |
4400 | * 1 to 4294967295 (see 5.3.1 for Tag value selection). ... | |
4401 | */ | |
4402 | ||
4403 | repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0); | |
4404 | if (!repl) | |
4405 | goto nomem; | |
4406 | ||
4407 | /* Cast away the const modifier, as we want to just | |
4408 | * rerun it through as a sideffect. | |
4409 | */ | |
ab38fb04 VY |
4410 | my_asoc = (struct sctp_association *)asoc; |
4411 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(my_asoc)); | |
1da177e4 | 4412 | |
3f7a87d2 FF |
4413 | /* Choose transport for INIT. */ |
4414 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4415 | SCTP_CHUNK(repl)); | |
4416 | ||
1da177e4 LT |
4417 | /* After sending the INIT, "A" starts the T1-init timer and |
4418 | * enters the COOKIE-WAIT state. | |
4419 | */ | |
4420 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4421 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4422 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4423 | return SCTP_DISPOSITION_CONSUME; | |
4424 | ||
4425 | nomem: | |
4426 | return SCTP_DISPOSITION_NOMEM; | |
4427 | } | |
4428 | ||
4429 | /* | |
4430 | * Process the SEND primitive. | |
4431 | * | |
4432 | * Section: 10.1 ULP-to-SCTP | |
4433 | * E) Send | |
4434 | * | |
4435 | * Format: SEND(association id, buffer address, byte count [,context] | |
4436 | * [,stream id] [,life time] [,destination transport address] | |
4437 | * [,unorder flag] [,no-bundle flag] [,payload protocol-id] ) | |
4438 | * -> result | |
4439 | * | |
4440 | * This is the main method to send user data via SCTP. | |
4441 | * | |
4442 | * Mandatory attributes: | |
4443 | * | |
4444 | * o association id - local handle to the SCTP association | |
4445 | * | |
4446 | * o buffer address - the location where the user message to be | |
4447 | * transmitted is stored; | |
4448 | * | |
4449 | * o byte count - The size of the user data in number of bytes; | |
4450 | * | |
4451 | * Optional attributes: | |
4452 | * | |
4453 | * o context - an optional 32 bit integer that will be carried in the | |
4454 | * sending failure notification to the ULP if the transportation of | |
4455 | * this User Message fails. | |
4456 | * | |
4457 | * o stream id - to indicate which stream to send the data on. If not | |
4458 | * specified, stream 0 will be used. | |
4459 | * | |
4460 | * o life time - specifies the life time of the user data. The user data | |
4461 | * will not be sent by SCTP after the life time expires. This | |
4462 | * parameter can be used to avoid efforts to transmit stale | |
4463 | * user messages. SCTP notifies the ULP if the data cannot be | |
4464 | * initiated to transport (i.e. sent to the destination via SCTP's | |
4465 | * send primitive) within the life time variable. However, the | |
4466 | * user data will be transmitted if SCTP has attempted to transmit a | |
4467 | * chunk before the life time expired. | |
4468 | * | |
4469 | * o destination transport address - specified as one of the destination | |
4470 | * transport addresses of the peer endpoint to which this packet | |
4471 | * should be sent. Whenever possible, SCTP should use this destination | |
4472 | * transport address for sending the packets, instead of the current | |
4473 | * primary path. | |
4474 | * | |
4475 | * o unorder flag - this flag, if present, indicates that the user | |
4476 | * would like the data delivered in an unordered fashion to the peer | |
4477 | * (i.e., the U flag is set to 1 on all DATA chunks carrying this | |
4478 | * message). | |
4479 | * | |
4480 | * o no-bundle flag - instructs SCTP not to bundle this user data with | |
4481 | * other outbound DATA chunks. SCTP MAY still bundle even when | |
4482 | * this flag is present, when faced with network congestion. | |
4483 | * | |
4484 | * o payload protocol-id - A 32 bit unsigned integer that is to be | |
4485 | * passed to the peer indicating the type of payload protocol data | |
4486 | * being transmitted. This value is passed as opaque data by SCTP. | |
4487 | * | |
4488 | * The return value is the disposition. | |
4489 | */ | |
4490 | sctp_disposition_t sctp_sf_do_prm_send(const struct sctp_endpoint *ep, | |
4491 | const struct sctp_association *asoc, | |
4492 | const sctp_subtype_t type, | |
4493 | void *arg, | |
4494 | sctp_cmd_seq_t *commands) | |
4495 | { | |
4496 | struct sctp_chunk *chunk = arg; | |
4497 | ||
4498 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
4499 | return SCTP_DISPOSITION_CONSUME; | |
4500 | } | |
4501 | ||
4502 | /* | |
4503 | * Process the SHUTDOWN primitive. | |
4504 | * | |
4505 | * Section: 10.1: | |
4506 | * C) Shutdown | |
4507 | * | |
4508 | * Format: SHUTDOWN(association id) | |
4509 | * -> result | |
4510 | * | |
4511 | * Gracefully closes an association. Any locally queued user data | |
4512 | * will be delivered to the peer. The association will be terminated only | |
4513 | * after the peer acknowledges all the SCTP packets sent. A success code | |
4514 | * will be returned on successful termination of the association. If | |
4515 | * attempting to terminate the association results in a failure, an error | |
4516 | * code shall be returned. | |
4517 | * | |
4518 | * Mandatory attributes: | |
4519 | * | |
4520 | * o association id - local handle to the SCTP association | |
4521 | * | |
4522 | * Optional attributes: | |
4523 | * | |
4524 | * None. | |
4525 | * | |
4526 | * The return value is the disposition. | |
4527 | */ | |
4528 | sctp_disposition_t sctp_sf_do_9_2_prm_shutdown( | |
4529 | const struct sctp_endpoint *ep, | |
4530 | const struct sctp_association *asoc, | |
4531 | const sctp_subtype_t type, | |
4532 | void *arg, | |
4533 | sctp_cmd_seq_t *commands) | |
4534 | { | |
4535 | int disposition; | |
4536 | ||
4537 | /* From 9.2 Shutdown of an Association | |
4538 | * Upon receipt of the SHUTDOWN primitive from its upper | |
4539 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
4540 | * remains there until all outstanding data has been | |
4541 | * acknowledged by its peer. The endpoint accepts no new data | |
4542 | * from its upper layer, but retransmits data to the far end | |
4543 | * if necessary to fill gaps. | |
4544 | */ | |
4545 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4546 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
4547 | ||
1da177e4 LT |
4548 | disposition = SCTP_DISPOSITION_CONSUME; |
4549 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
4550 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
4551 | arg, commands); | |
4552 | } | |
4553 | return disposition; | |
4554 | } | |
4555 | ||
4556 | /* | |
4557 | * Process the ABORT primitive. | |
4558 | * | |
4559 | * Section: 10.1: | |
4560 | * C) Abort | |
4561 | * | |
4562 | * Format: Abort(association id [, cause code]) | |
4563 | * -> result | |
4564 | * | |
4565 | * Ungracefully closes an association. Any locally queued user data | |
4566 | * will be discarded and an ABORT chunk is sent to the peer. A success code | |
4567 | * will be returned on successful abortion of the association. If | |
4568 | * attempting to abort the association results in a failure, an error | |
4569 | * code shall be returned. | |
4570 | * | |
4571 | * Mandatory attributes: | |
4572 | * | |
4573 | * o association id - local handle to the SCTP association | |
4574 | * | |
4575 | * Optional attributes: | |
4576 | * | |
4577 | * o cause code - reason of the abort to be passed to the peer | |
4578 | * | |
4579 | * None. | |
4580 | * | |
4581 | * The return value is the disposition. | |
4582 | */ | |
4583 | sctp_disposition_t sctp_sf_do_9_1_prm_abort( | |
4584 | const struct sctp_endpoint *ep, | |
4585 | const struct sctp_association *asoc, | |
4586 | const sctp_subtype_t type, | |
4587 | void *arg, | |
4588 | sctp_cmd_seq_t *commands) | |
4589 | { | |
4590 | /* From 9.1 Abort of an Association | |
4591 | * Upon receipt of the ABORT primitive from its upper | |
4592 | * layer, the endpoint enters CLOSED state and | |
4593 | * discard all outstanding data has been | |
4594 | * acknowledged by its peer. The endpoint accepts no new data | |
4595 | * from its upper layer, but retransmits data to the far end | |
4596 | * if necessary to fill gaps. | |
4597 | */ | |
c164a9ba | 4598 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4599 | sctp_disposition_t retval; |
4600 | ||
4601 | retval = SCTP_DISPOSITION_CONSUME; | |
4602 | ||
c164a9ba | 4603 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4604 | |
4605 | /* Even if we can't send the ABORT due to low memory delete the | |
4606 | * TCB. This is a departure from our typical NOMEM handling. | |
4607 | */ | |
4608 | ||
8de8c873 SS |
4609 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4610 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 LT |
4611 | /* Delete the established association. */ |
4612 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4613 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4614 | |
4615 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4616 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4617 | ||
4618 | return retval; | |
4619 | } | |
4620 | ||
4621 | /* We tried an illegal operation on an association which is closed. */ | |
4622 | sctp_disposition_t sctp_sf_error_closed(const struct sctp_endpoint *ep, | |
4623 | const struct sctp_association *asoc, | |
4624 | const sctp_subtype_t type, | |
4625 | void *arg, | |
4626 | sctp_cmd_seq_t *commands) | |
4627 | { | |
4628 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL)); | |
4629 | return SCTP_DISPOSITION_CONSUME; | |
4630 | } | |
4631 | ||
4632 | /* We tried an illegal operation on an association which is shutting | |
4633 | * down. | |
4634 | */ | |
4635 | sctp_disposition_t sctp_sf_error_shutdown(const struct sctp_endpoint *ep, | |
4636 | const struct sctp_association *asoc, | |
4637 | const sctp_subtype_t type, | |
4638 | void *arg, | |
4639 | sctp_cmd_seq_t *commands) | |
4640 | { | |
4641 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, | |
4642 | SCTP_ERROR(-ESHUTDOWN)); | |
4643 | return SCTP_DISPOSITION_CONSUME; | |
4644 | } | |
4645 | ||
4646 | /* | |
4647 | * sctp_cookie_wait_prm_shutdown | |
4648 | * | |
4649 | * Section: 4 Note: 2 | |
4650 | * Verification Tag: | |
4651 | * Inputs | |
4652 | * (endpoint, asoc) | |
4653 | * | |
4654 | * The RFC does not explicitly address this issue, but is the route through the | |
4655 | * state table when someone issues a shutdown while in COOKIE_WAIT state. | |
4656 | * | |
4657 | * Outputs | |
4658 | * (timers) | |
4659 | */ | |
4660 | sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown( | |
4661 | const struct sctp_endpoint *ep, | |
4662 | const struct sctp_association *asoc, | |
4663 | const sctp_subtype_t type, | |
4664 | void *arg, | |
4665 | sctp_cmd_seq_t *commands) | |
4666 | { | |
4667 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4668 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4669 | ||
4670 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4671 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4672 | ||
4673 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
4674 | ||
4675 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
4676 | ||
4677 | return SCTP_DISPOSITION_DELETE_TCB; | |
4678 | } | |
4679 | ||
4680 | /* | |
4681 | * sctp_cookie_echoed_prm_shutdown | |
4682 | * | |
4683 | * Section: 4 Note: 2 | |
4684 | * Verification Tag: | |
4685 | * Inputs | |
4686 | * (endpoint, asoc) | |
4687 | * | |
4688 | * The RFC does not explcitly address this issue, but is the route through the | |
4689 | * state table when someone issues a shutdown while in COOKIE_ECHOED state. | |
4690 | * | |
4691 | * Outputs | |
4692 | * (timers) | |
4693 | */ | |
4694 | sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown( | |
4695 | const struct sctp_endpoint *ep, | |
4696 | const struct sctp_association *asoc, | |
4697 | const sctp_subtype_t type, | |
4698 | void *arg, sctp_cmd_seq_t *commands) | |
4699 | { | |
4700 | /* There is a single T1 timer, so we should be able to use | |
4701 | * common function with the COOKIE-WAIT state. | |
4702 | */ | |
4703 | return sctp_sf_cookie_wait_prm_shutdown(ep, asoc, type, arg, commands); | |
4704 | } | |
4705 | ||
4706 | /* | |
4707 | * sctp_sf_cookie_wait_prm_abort | |
4708 | * | |
4709 | * Section: 4 Note: 2 | |
4710 | * Verification Tag: | |
4711 | * Inputs | |
4712 | * (endpoint, asoc) | |
4713 | * | |
4714 | * The RFC does not explicitly address this issue, but is the route through the | |
4715 | * state table when someone issues an abort while in COOKIE_WAIT state. | |
4716 | * | |
4717 | * Outputs | |
4718 | * (timers) | |
4719 | */ | |
4720 | sctp_disposition_t sctp_sf_cookie_wait_prm_abort( | |
4721 | 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 | { | |
c164a9ba | 4727 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4728 | sctp_disposition_t retval; |
4729 | ||
4730 | /* Stop T1-init timer */ | |
4731 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4732 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4733 | retval = SCTP_DISPOSITION_CONSUME; | |
4734 | ||
c164a9ba | 4735 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4736 | |
4737 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4738 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4739 | ||
4740 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4741 | ||
4742 | /* Even if we can't send the ABORT due to low memory delete the | |
4743 | * TCB. This is a departure from our typical NOMEM handling. | |
4744 | */ | |
4745 | ||
8de8c873 SS |
4746 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4747 | SCTP_ERROR(ECONNREFUSED)); | |
1da177e4 LT |
4748 | /* Delete the established association. */ |
4749 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 4750 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4751 | |
4752 | return retval; | |
4753 | } | |
4754 | ||
4755 | /* | |
4756 | * sctp_sf_cookie_echoed_prm_abort | |
4757 | * | |
4758 | * Section: 4 Note: 3 | |
4759 | * Verification Tag: | |
4760 | * Inputs | |
4761 | * (endpoint, asoc) | |
4762 | * | |
4763 | * The RFC does not explcitly address this issue, but is the route through the | |
4764 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4765 | * | |
4766 | * Outputs | |
4767 | * (timers) | |
4768 | */ | |
4769 | sctp_disposition_t sctp_sf_cookie_echoed_prm_abort( | |
4770 | const struct sctp_endpoint *ep, | |
4771 | const struct sctp_association *asoc, | |
4772 | const sctp_subtype_t type, | |
4773 | void *arg, | |
4774 | sctp_cmd_seq_t *commands) | |
4775 | { | |
4776 | /* There is a single T1 timer, so we should be able to use | |
4777 | * common function with the COOKIE-WAIT state. | |
4778 | */ | |
4779 | return sctp_sf_cookie_wait_prm_abort(ep, asoc, type, arg, commands); | |
4780 | } | |
4781 | ||
4782 | /* | |
4783 | * sctp_sf_shutdown_pending_prm_abort | |
4784 | * | |
4785 | * Inputs | |
4786 | * (endpoint, asoc) | |
4787 | * | |
4788 | * The RFC does not explicitly address this issue, but is the route through the | |
4789 | * state table when someone issues an abort while in SHUTDOWN-PENDING state. | |
4790 | * | |
4791 | * Outputs | |
4792 | * (timers) | |
4793 | */ | |
4794 | sctp_disposition_t sctp_sf_shutdown_pending_prm_abort( | |
4795 | const struct sctp_endpoint *ep, | |
4796 | const struct sctp_association *asoc, | |
4797 | const sctp_subtype_t type, | |
4798 | void *arg, | |
4799 | sctp_cmd_seq_t *commands) | |
4800 | { | |
4801 | /* Stop the T5-shutdown guard timer. */ | |
4802 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4803 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4804 | ||
4805 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4806 | } | |
4807 | ||
4808 | /* | |
4809 | * sctp_sf_shutdown_sent_prm_abort | |
4810 | * | |
4811 | * Inputs | |
4812 | * (endpoint, asoc) | |
4813 | * | |
4814 | * The RFC does not explicitly address this issue, but is the route through the | |
4815 | * state table when someone issues an abort while in SHUTDOWN-SENT state. | |
4816 | * | |
4817 | * Outputs | |
4818 | * (timers) | |
4819 | */ | |
4820 | sctp_disposition_t sctp_sf_shutdown_sent_prm_abort( | |
4821 | const struct sctp_endpoint *ep, | |
4822 | const struct sctp_association *asoc, | |
4823 | const sctp_subtype_t type, | |
4824 | void *arg, | |
4825 | sctp_cmd_seq_t *commands) | |
4826 | { | |
4827 | /* Stop the T2-shutdown timer. */ | |
4828 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4829 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4830 | ||
4831 | /* Stop the T5-shutdown guard timer. */ | |
4832 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4833 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4834 | ||
4835 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4836 | } | |
4837 | ||
4838 | /* | |
4839 | * sctp_sf_cookie_echoed_prm_abort | |
4840 | * | |
4841 | * Inputs | |
4842 | * (endpoint, asoc) | |
4843 | * | |
4844 | * The RFC does not explcitly address this issue, but is the route through the | |
4845 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4846 | * | |
4847 | * Outputs | |
4848 | * (timers) | |
4849 | */ | |
4850 | sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort( | |
4851 | const struct sctp_endpoint *ep, | |
4852 | const struct sctp_association *asoc, | |
4853 | const sctp_subtype_t type, | |
4854 | void *arg, | |
4855 | sctp_cmd_seq_t *commands) | |
4856 | { | |
4857 | /* The same T2 timer, so we should be able to use | |
4858 | * common function with the SHUTDOWN-SENT state. | |
4859 | */ | |
4860 | return sctp_sf_shutdown_sent_prm_abort(ep, asoc, type, arg, commands); | |
4861 | } | |
4862 | ||
4863 | /* | |
4864 | * Process the REQUESTHEARTBEAT primitive | |
4865 | * | |
4866 | * 10.1 ULP-to-SCTP | |
4867 | * J) Request Heartbeat | |
4868 | * | |
4869 | * Format: REQUESTHEARTBEAT(association id, destination transport address) | |
4870 | * | |
4871 | * -> result | |
4872 | * | |
4873 | * Instructs the local endpoint to perform a HeartBeat on the specified | |
4874 | * destination transport address of the given association. The returned | |
4875 | * result should indicate whether the transmission of the HEARTBEAT | |
4876 | * chunk to the destination address is successful. | |
4877 | * | |
4878 | * Mandatory attributes: | |
4879 | * | |
4880 | * o association id - local handle to the SCTP association | |
4881 | * | |
4882 | * o destination transport address - the transport address of the | |
4883 | * association on which a heartbeat should be issued. | |
4884 | */ | |
4885 | sctp_disposition_t sctp_sf_do_prm_requestheartbeat( | |
4886 | const struct sctp_endpoint *ep, | |
4887 | const struct sctp_association *asoc, | |
4888 | const sctp_subtype_t type, | |
4889 | void *arg, | |
4890 | sctp_cmd_seq_t *commands) | |
4891 | { | |
fb78525a VY |
4892 | if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type, |
4893 | (struct sctp_transport *)arg, commands)) | |
4894 | return SCTP_DISPOSITION_NOMEM; | |
4895 | ||
4896 | /* | |
4897 | * RFC 2960 (bis), section 8.3 | |
4898 | * | |
4899 | * D) Request an on-demand HEARTBEAT on a specific destination | |
4900 | * transport address of a given association. | |
4901 | * | |
4902 | * The endpoint should increment the respective error counter of | |
4903 | * the destination transport address each time a HEARTBEAT is sent | |
4904 | * to that address and not acknowledged within one RTO. | |
4905 | * | |
4906 | */ | |
4907 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_RESET, | |
4908 | SCTP_TRANSPORT(arg)); | |
4909 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
4910 | } |
4911 | ||
4912 | /* | |
4913 | * ADDIP Section 4.1 ASCONF Chunk Procedures | |
4914 | * When an endpoint has an ASCONF signaled change to be sent to the | |
4915 | * remote endpoint it should do A1 to A9 | |
4916 | */ | |
4917 | sctp_disposition_t sctp_sf_do_prm_asconf(const struct sctp_endpoint *ep, | |
4918 | const struct sctp_association *asoc, | |
4919 | const sctp_subtype_t type, | |
4920 | void *arg, | |
4921 | sctp_cmd_seq_t *commands) | |
4922 | { | |
4923 | struct sctp_chunk *chunk = arg; | |
4924 | ||
4925 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
4926 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4927 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
4928 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
4929 | return SCTP_DISPOSITION_CONSUME; | |
4930 | } | |
4931 | ||
4932 | /* | |
4933 | * Ignore the primitive event | |
4934 | * | |
4935 | * The return value is the disposition of the primitive. | |
4936 | */ | |
4937 | sctp_disposition_t sctp_sf_ignore_primitive( | |
4938 | const struct sctp_endpoint *ep, | |
4939 | const struct sctp_association *asoc, | |
4940 | const sctp_subtype_t type, | |
4941 | void *arg, | |
4942 | sctp_cmd_seq_t *commands) | |
4943 | { | |
4944 | SCTP_DEBUG_PRINTK("Primitive type %d is ignored.\n", type.primitive); | |
4945 | return SCTP_DISPOSITION_DISCARD; | |
4946 | } | |
4947 | ||
4948 | /*************************************************************************** | |
4949 | * These are the state functions for the OTHER events. | |
4950 | ***************************************************************************/ | |
4951 | ||
4952 | /* | |
4953 | * Start the shutdown negotiation. | |
4954 | * | |
4955 | * From Section 9.2: | |
4956 | * Once all its outstanding data has been acknowledged, the endpoint | |
4957 | * shall send a SHUTDOWN chunk to its peer including in the Cumulative | |
4958 | * TSN Ack field the last sequential TSN it has received from the peer. | |
4959 | * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT | |
4960 | * state. If the timer expires, the endpoint must re-send the SHUTDOWN | |
4961 | * with the updated last sequential TSN received from its peer. | |
4962 | * | |
4963 | * The return value is the disposition. | |
4964 | */ | |
4965 | sctp_disposition_t sctp_sf_do_9_2_start_shutdown( | |
4966 | const struct sctp_endpoint *ep, | |
4967 | const struct sctp_association *asoc, | |
4968 | const sctp_subtype_t type, | |
4969 | void *arg, | |
4970 | sctp_cmd_seq_t *commands) | |
4971 | { | |
4972 | struct sctp_chunk *reply; | |
4973 | ||
4974 | /* Once all its outstanding data has been acknowledged, the | |
4975 | * endpoint shall send a SHUTDOWN chunk to its peer including | |
4976 | * in the Cumulative TSN Ack field the last sequential TSN it | |
4977 | * has received from the peer. | |
4978 | */ | |
4979 | reply = sctp_make_shutdown(asoc, NULL); | |
4980 | if (!reply) | |
4981 | goto nomem; | |
4982 | ||
4983 | /* Set the transport for the SHUTDOWN chunk and the timeout for the | |
4984 | * T2-shutdown timer. | |
4985 | */ | |
4986 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
4987 | ||
4988 | /* It shall then start the T2-shutdown timer */ | |
4989 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4990 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4991 | ||
536428a9 WY |
4992 | /* RFC 4960 Section 9.2 |
4993 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
4994 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
4995 | */ | |
4996 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4997 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4998 | ||
1da177e4 LT |
4999 | if (asoc->autoclose) |
5000 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5001 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5002 | ||
5003 | /* and enter the SHUTDOWN-SENT state. */ | |
5004 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5005 | SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT)); | |
5006 | ||
5007 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5008 | * | |
5009 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5010 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5011 | */ |
5012 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5013 | ||
5014 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5015 | ||
5016 | return SCTP_DISPOSITION_CONSUME; | |
5017 | ||
5018 | nomem: | |
5019 | return SCTP_DISPOSITION_NOMEM; | |
5020 | } | |
5021 | ||
5022 | /* | |
5023 | * Generate a SHUTDOWN ACK now that everything is SACK'd. | |
5024 | * | |
5025 | * From Section 9.2: | |
5026 | * | |
5027 | * If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5028 | * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own, | |
5029 | * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the | |
5030 | * endpoint must re-send the SHUTDOWN ACK. | |
5031 | * | |
5032 | * The return value is the disposition. | |
5033 | */ | |
5034 | sctp_disposition_t sctp_sf_do_9_2_shutdown_ack( | |
5035 | const struct sctp_endpoint *ep, | |
5036 | const struct sctp_association *asoc, | |
5037 | const sctp_subtype_t type, | |
5038 | void *arg, | |
5039 | sctp_cmd_seq_t *commands) | |
5040 | { | |
5041 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
5042 | struct sctp_chunk *reply; | |
5043 | ||
5044 | /* There are 2 ways of getting here: | |
5045 | * 1) called in response to a SHUTDOWN chunk | |
5046 | * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued. | |
5047 | * | |
5048 | * For the case (2), the arg parameter is set to NULL. We need | |
5049 | * to check that we have a chunk before accessing it's fields. | |
5050 | */ | |
5051 | if (chunk) { | |
5052 | if (!sctp_vtag_verify(chunk, asoc)) | |
5053 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
5054 | ||
5055 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
5056 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t))) | |
5057 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
5058 | commands); | |
5059 | } | |
5060 | ||
5061 | /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
5062 | * shall send a SHUTDOWN ACK ... | |
5063 | */ | |
5064 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
5065 | if (!reply) | |
5066 | goto nomem; | |
5067 | ||
5068 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
5069 | * the T2-shutdown timer. | |
5070 | */ | |
5071 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5072 | ||
5073 | /* and start/restart a T2-shutdown timer of its own, */ | |
5074 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5075 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5076 | ||
5077 | if (asoc->autoclose) | |
5078 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5079 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
5080 | ||
5081 | /* Enter the SHUTDOWN-ACK-SENT state. */ | |
5082 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5083 | SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT)); | |
5084 | ||
5085 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
5086 | * | |
5087 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 5088 | * or SHUTDOWN-ACK. |
1da177e4 LT |
5089 | */ |
5090 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
5091 | ||
5092 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5093 | ||
5094 | return SCTP_DISPOSITION_CONSUME; | |
5095 | ||
5096 | nomem: | |
5097 | return SCTP_DISPOSITION_NOMEM; | |
5098 | } | |
5099 | ||
5100 | /* | |
5101 | * Ignore the event defined as other | |
5102 | * | |
5103 | * The return value is the disposition of the event. | |
5104 | */ | |
5105 | sctp_disposition_t sctp_sf_ignore_other(const struct sctp_endpoint *ep, | |
5106 | const struct sctp_association *asoc, | |
5107 | const sctp_subtype_t type, | |
5108 | void *arg, | |
5109 | sctp_cmd_seq_t *commands) | |
5110 | { | |
5111 | SCTP_DEBUG_PRINTK("The event other type %d is ignored\n", type.other); | |
5112 | return SCTP_DISPOSITION_DISCARD; | |
5113 | } | |
5114 | ||
5115 | /************************************************************ | |
5116 | * These are the state functions for handling timeout events. | |
5117 | ************************************************************/ | |
5118 | ||
5119 | /* | |
5120 | * RTX Timeout | |
5121 | * | |
5122 | * Section: 6.3.3 Handle T3-rtx Expiration | |
5123 | * | |
5124 | * Whenever the retransmission timer T3-rtx expires for a destination | |
5125 | * address, do the following: | |
5126 | * [See below] | |
5127 | * | |
5128 | * The return value is the disposition of the chunk. | |
5129 | */ | |
5130 | sctp_disposition_t sctp_sf_do_6_3_3_rtx(const struct sctp_endpoint *ep, | |
5131 | const struct sctp_association *asoc, | |
5132 | const sctp_subtype_t type, | |
5133 | void *arg, | |
5134 | sctp_cmd_seq_t *commands) | |
5135 | { | |
5136 | struct sctp_transport *transport = arg; | |
5137 | ||
ac0b0462 SS |
5138 | SCTP_INC_STATS(SCTP_MIB_T3_RTX_EXPIREDS); |
5139 | ||
1da177e4 | 5140 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5141 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5142 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5143 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5144 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5145 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5146 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5147 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5148 | return SCTP_DISPOSITION_DELETE_TCB; | |
5149 | } | |
5150 | ||
5151 | /* E1) For the destination address for which the timer | |
5152 | * expires, adjust its ssthresh with rules defined in Section | |
5153 | * 7.2.3 and set the cwnd <- MTU. | |
5154 | */ | |
5155 | ||
5156 | /* E2) For the destination address for which the timer | |
5157 | * expires, set RTO <- RTO * 2 ("back off the timer"). The | |
5158 | * maximum value discussed in rule C7 above (RTO.max) may be | |
5159 | * used to provide an upper bound to this doubling operation. | |
5160 | */ | |
5161 | ||
5162 | /* E3) Determine how many of the earliest (i.e., lowest TSN) | |
5163 | * outstanding DATA chunks for the address for which the | |
5164 | * T3-rtx has expired will fit into a single packet, subject | |
5165 | * to the MTU constraint for the path corresponding to the | |
5166 | * destination transport address to which the retransmission | |
5167 | * is being sent (this may be different from the address for | |
5168 | * which the timer expires [see Section 6.4]). Call this | |
5169 | * value K. Bundle and retransmit those K DATA chunks in a | |
5170 | * single packet to the destination endpoint. | |
5171 | * | |
5172 | * Note: Any DATA chunks that were sent to the address for | |
5173 | * which the T3-rtx timer expired but did not fit in one MTU | |
5174 | * (rule E3 above), should be marked for retransmission and | |
5175 | * sent as soon as cwnd allows (normally when a SACK arrives). | |
5176 | */ | |
5177 | ||
1da177e4 LT |
5178 | /* Do some failure management (Section 8.2). */ |
5179 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5180 | ||
1845a579 VY |
5181 | /* NB: Rules E4 and F1 are implicit in R1. */ |
5182 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport)); | |
5183 | ||
1da177e4 LT |
5184 | return SCTP_DISPOSITION_CONSUME; |
5185 | } | |
5186 | ||
5187 | /* | |
5188 | * Generate delayed SACK on timeout | |
5189 | * | |
5190 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
5191 | * | |
5192 | * The guidelines on delayed acknowledgement algorithm specified in | |
5193 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
5194 | * acknowledgement SHOULD be generated for at least every second packet | |
5195 | * (not every second DATA chunk) received, and SHOULD be generated | |
5196 | * within 200 ms of the arrival of any unacknowledged DATA chunk. In | |
5197 | * some situations it may be beneficial for an SCTP transmitter to be | |
5198 | * more conservative than the algorithms detailed in this document | |
5199 | * allow. However, an SCTP transmitter MUST NOT be more aggressive than | |
5200 | * the following algorithms allow. | |
5201 | */ | |
5202 | sctp_disposition_t sctp_sf_do_6_2_sack(const struct sctp_endpoint *ep, | |
5203 | const struct sctp_association *asoc, | |
5204 | const sctp_subtype_t type, | |
5205 | void *arg, | |
5206 | sctp_cmd_seq_t *commands) | |
5207 | { | |
ac0b0462 | 5208 | SCTP_INC_STATS(SCTP_MIB_DELAY_SACK_EXPIREDS); |
1da177e4 LT |
5209 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); |
5210 | return SCTP_DISPOSITION_CONSUME; | |
5211 | } | |
5212 | ||
5213 | /* | |
3f7a87d2 | 5214 | * sctp_sf_t1_init_timer_expire |
1da177e4 LT |
5215 | * |
5216 | * Section: 4 Note: 2 | |
5217 | * Verification Tag: | |
5218 | * Inputs | |
5219 | * (endpoint, asoc) | |
5220 | * | |
5221 | * RFC 2960 Section 4 Notes | |
5222 | * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT | |
5223 | * and re-start the T1-init timer without changing state. This MUST | |
5224 | * be repeated up to 'Max.Init.Retransmits' times. After that, the | |
5225 | * endpoint MUST abort the initialization process and report the | |
5226 | * error to SCTP user. | |
5227 | * | |
3f7a87d2 FF |
5228 | * Outputs |
5229 | * (timers, events) | |
5230 | * | |
5231 | */ | |
5232 | sctp_disposition_t sctp_sf_t1_init_timer_expire(const struct sctp_endpoint *ep, | |
5233 | const struct sctp_association *asoc, | |
5234 | const sctp_subtype_t type, | |
5235 | void *arg, | |
5236 | sctp_cmd_seq_t *commands) | |
5237 | { | |
5238 | struct sctp_chunk *repl = NULL; | |
5239 | struct sctp_bind_addr *bp; | |
5240 | int attempts = asoc->init_err_counter + 1; | |
5241 | ||
5242 | SCTP_DEBUG_PRINTK("Timer T1 expired (INIT).\n"); | |
ac0b0462 | 5243 | SCTP_INC_STATS(SCTP_MIB_T1_INIT_EXPIREDS); |
3f7a87d2 | 5244 | |
81845c21 | 5245 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 FF |
5246 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; |
5247 | repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0); | |
5248 | if (!repl) | |
5249 | return SCTP_DISPOSITION_NOMEM; | |
5250 | ||
5251 | /* Choose transport for INIT. */ | |
5252 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
5253 | SCTP_CHUNK(repl)); | |
5254 | ||
5255 | /* Issue a sideeffect to do the needed accounting. */ | |
5256 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART, | |
5257 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
5258 | ||
5259 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
5260 | } else { | |
5261 | SCTP_DEBUG_PRINTK("Giving up on INIT, attempts: %d" | |
5262 | " max_init_attempts: %d\n", | |
5263 | attempts, asoc->max_init_attempts); | |
8de8c873 SS |
5264 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5265 | SCTP_ERROR(ETIMEDOUT)); | |
3f7a87d2 | 5266 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5267 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
3f7a87d2 FF |
5268 | return SCTP_DISPOSITION_DELETE_TCB; |
5269 | } | |
5270 | ||
5271 | return SCTP_DISPOSITION_CONSUME; | |
5272 | } | |
5273 | ||
5274 | /* | |
5275 | * sctp_sf_t1_cookie_timer_expire | |
5276 | * | |
5277 | * Section: 4 Note: 2 | |
5278 | * Verification Tag: | |
5279 | * Inputs | |
5280 | * (endpoint, asoc) | |
5281 | * | |
5282 | * RFC 2960 Section 4 Notes | |
5283 | * 3) If the T1-cookie timer expires, the endpoint MUST retransmit | |
1da177e4 LT |
5284 | * COOKIE ECHO and re-start the T1-cookie timer without changing |
5285 | * state. This MUST be repeated up to 'Max.Init.Retransmits' times. | |
5286 | * After that, the endpoint MUST abort the initialization process and | |
5287 | * report the error to SCTP user. | |
5288 | * | |
5289 | * Outputs | |
5290 | * (timers, events) | |
5291 | * | |
5292 | */ | |
3f7a87d2 | 5293 | sctp_disposition_t sctp_sf_t1_cookie_timer_expire(const struct sctp_endpoint *ep, |
1da177e4 LT |
5294 | const struct sctp_association *asoc, |
5295 | const sctp_subtype_t type, | |
5296 | void *arg, | |
5297 | sctp_cmd_seq_t *commands) | |
5298 | { | |
3f7a87d2 FF |
5299 | struct sctp_chunk *repl = NULL; |
5300 | int attempts = asoc->init_err_counter + 1; | |
1da177e4 | 5301 | |
3f7a87d2 | 5302 | SCTP_DEBUG_PRINTK("Timer T1 expired (COOKIE-ECHO).\n"); |
ac0b0462 | 5303 | SCTP_INC_STATS(SCTP_MIB_T1_COOKIE_EXPIREDS); |
1da177e4 | 5304 | |
81845c21 | 5305 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 | 5306 | repl = sctp_make_cookie_echo(asoc, NULL); |
1da177e4 | 5307 | if (!repl) |
3f7a87d2 | 5308 | return SCTP_DISPOSITION_NOMEM; |
1da177e4 | 5309 | |
96cd0d3d VY |
5310 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, |
5311 | SCTP_CHUNK(repl)); | |
1da177e4 | 5312 | /* Issue a sideeffect to do the needed accounting. */ |
3f7a87d2 FF |
5313 | sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART, |
5314 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
5315 | ||
1da177e4 LT |
5316 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
5317 | } else { | |
8de8c873 SS |
5318 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5319 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5320 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 5321 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5322 | return SCTP_DISPOSITION_DELETE_TCB; |
5323 | } | |
5324 | ||
5325 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
5326 | } |
5327 | ||
5328 | /* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN | |
5329 | * with the updated last sequential TSN received from its peer. | |
5330 | * | |
5331 | * An endpoint should limit the number of retransmissions of the | |
5332 | * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'. | |
5333 | * If this threshold is exceeded the endpoint should destroy the TCB and | |
5334 | * MUST report the peer endpoint unreachable to the upper layer (and | |
5335 | * thus the association enters the CLOSED state). The reception of any | |
5336 | * packet from its peer (i.e. as the peer sends all of its queued DATA | |
5337 | * chunks) should clear the endpoint's retransmission count and restart | |
5338 | * the T2-Shutdown timer, giving its peer ample opportunity to transmit | |
5339 | * all of its queued DATA chunks that have not yet been sent. | |
5340 | */ | |
5341 | sctp_disposition_t sctp_sf_t2_timer_expire(const struct sctp_endpoint *ep, | |
5342 | const struct sctp_association *asoc, | |
5343 | const sctp_subtype_t type, | |
5344 | void *arg, | |
5345 | sctp_cmd_seq_t *commands) | |
5346 | { | |
5347 | struct sctp_chunk *reply = NULL; | |
5348 | ||
5349 | SCTP_DEBUG_PRINTK("Timer T2 expired.\n"); | |
ac0b0462 SS |
5350 | SCTP_INC_STATS(SCTP_MIB_T2_SHUTDOWN_EXPIREDS); |
5351 | ||
58fbbed4 NH |
5352 | ((struct sctp_association *)asoc)->shutdown_retries++; |
5353 | ||
1da177e4 | 5354 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
5355 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5356 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
5357 | /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
5358 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 5359 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5360 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5361 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5362 | return SCTP_DISPOSITION_DELETE_TCB; | |
5363 | } | |
5364 | ||
5365 | switch (asoc->state) { | |
5366 | case SCTP_STATE_SHUTDOWN_SENT: | |
5367 | reply = sctp_make_shutdown(asoc, NULL); | |
5368 | break; | |
5369 | ||
5370 | case SCTP_STATE_SHUTDOWN_ACK_SENT: | |
5371 | reply = sctp_make_shutdown_ack(asoc, NULL); | |
5372 | break; | |
5373 | ||
5374 | default: | |
5375 | BUG(); | |
5376 | break; | |
3ff50b79 | 5377 | } |
1da177e4 LT |
5378 | |
5379 | if (!reply) | |
5380 | goto nomem; | |
5381 | ||
5382 | /* Do some failure management (Section 8.2). */ | |
5383 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
5384 | SCTP_TRANSPORT(asoc->shutdown_last_sent_to)); | |
5385 | ||
5386 | /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for | |
5387 | * the T2-shutdown timer. | |
5388 | */ | |
5389 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
5390 | ||
5391 | /* Restart the T2-shutdown timer. */ | |
5392 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5393 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
5394 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
5395 | return SCTP_DISPOSITION_CONSUME; | |
5396 | ||
5397 | nomem: | |
5398 | return SCTP_DISPOSITION_NOMEM; | |
5399 | } | |
5400 | ||
5401 | /* | |
5402 | * ADDIP Section 4.1 ASCONF CHunk Procedures | |
5403 | * If the T4 RTO timer expires the endpoint should do B1 to B5 | |
5404 | */ | |
5405 | sctp_disposition_t sctp_sf_t4_timer_expire( | |
5406 | const struct sctp_endpoint *ep, | |
5407 | const struct sctp_association *asoc, | |
5408 | const sctp_subtype_t type, | |
5409 | void *arg, | |
5410 | sctp_cmd_seq_t *commands) | |
5411 | { | |
5412 | struct sctp_chunk *chunk = asoc->addip_last_asconf; | |
5413 | struct sctp_transport *transport = chunk->transport; | |
5414 | ||
ac0b0462 SS |
5415 | SCTP_INC_STATS(SCTP_MIB_T4_RTO_EXPIREDS); |
5416 | ||
1da177e4 LT |
5417 | /* ADDIP 4.1 B1) Increment the error counters and perform path failure |
5418 | * detection on the appropriate destination address as defined in | |
5419 | * RFC2960 [5] section 8.1 and 8.2. | |
5420 | */ | |
5421 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5422 | ||
5423 | /* Reconfig T4 timer and transport. */ | |
5424 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5425 | ||
5426 | /* ADDIP 4.1 B2) Increment the association error counters and perform | |
5427 | * endpoint failure detection on the association as defined in | |
5428 | * RFC2960 [5] section 8.1 and 8.2. | |
5429 | * association error counter is incremented in SCTP_CMD_STRIKE. | |
5430 | */ | |
5431 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
5432 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5433 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
8de8c873 SS |
5434 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5435 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5436 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5437 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 | 5438 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3d5a019d | 5439 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); |
1da177e4 LT |
5440 | return SCTP_DISPOSITION_ABORT; |
5441 | } | |
5442 | ||
5443 | /* ADDIP 4.1 B3) Back-off the destination address RTO value to which | |
5444 | * the ASCONF chunk was sent by doubling the RTO timer value. | |
5445 | * This is done in SCTP_CMD_STRIKE. | |
5446 | */ | |
5447 | ||
5448 | /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible | |
5449 | * choose an alternate destination address (please refer to RFC2960 | |
5450 | * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this | |
d808ad9a | 5451 | * chunk, it MUST be the same (including its serial number) as the last |
1da177e4 LT |
5452 | * ASCONF sent. |
5453 | */ | |
5454 | sctp_chunk_hold(asoc->addip_last_asconf); | |
5455 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5456 | SCTP_CHUNK(asoc->addip_last_asconf)); | |
5457 | ||
5458 | /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different | |
5459 | * destination is selected, then the RTO used will be that of the new | |
5460 | * destination address. | |
5461 | */ | |
5462 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5463 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5464 | ||
5465 | return SCTP_DISPOSITION_CONSUME; | |
5466 | } | |
5467 | ||
5468 | /* sctpimpguide-05 Section 2.12.2 | |
5469 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5470 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5471 | * At the expiration of this timer the sender SHOULD abort the association | |
5472 | * by sending an ABORT chunk. | |
5473 | */ | |
5474 | sctp_disposition_t sctp_sf_t5_timer_expire(const struct sctp_endpoint *ep, | |
5475 | const struct sctp_association *asoc, | |
5476 | const sctp_subtype_t type, | |
5477 | void *arg, | |
5478 | sctp_cmd_seq_t *commands) | |
5479 | { | |
5480 | struct sctp_chunk *reply = NULL; | |
5481 | ||
5482 | SCTP_DEBUG_PRINTK("Timer T5 expired.\n"); | |
ac0b0462 | 5483 | SCTP_INC_STATS(SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS); |
1da177e4 LT |
5484 | |
5485 | reply = sctp_make_abort(asoc, NULL, 0); | |
5486 | if (!reply) | |
5487 | goto nomem; | |
5488 | ||
5489 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
8de8c873 SS |
5490 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5491 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5492 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5493 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5494 | |
5495 | return SCTP_DISPOSITION_DELETE_TCB; | |
5496 | nomem: | |
5497 | return SCTP_DISPOSITION_NOMEM; | |
5498 | } | |
5499 | ||
5500 | /* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires, | |
5501 | * the association is automatically closed by starting the shutdown process. | |
5502 | * The work that needs to be done is same as when SHUTDOWN is initiated by | |
5503 | * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown(). | |
5504 | */ | |
5505 | sctp_disposition_t sctp_sf_autoclose_timer_expire( | |
5506 | const struct sctp_endpoint *ep, | |
5507 | const struct sctp_association *asoc, | |
5508 | const sctp_subtype_t type, | |
5509 | void *arg, | |
5510 | sctp_cmd_seq_t *commands) | |
5511 | { | |
5512 | int disposition; | |
5513 | ||
ac0b0462 SS |
5514 | SCTP_INC_STATS(SCTP_MIB_AUTOCLOSE_EXPIREDS); |
5515 | ||
1da177e4 LT |
5516 | /* From 9.2 Shutdown of an Association |
5517 | * Upon receipt of the SHUTDOWN primitive from its upper | |
5518 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
5519 | * remains there until all outstanding data has been | |
5520 | * acknowledged by its peer. The endpoint accepts no new data | |
5521 | * from its upper layer, but retransmits data to the far end | |
5522 | * if necessary to fill gaps. | |
5523 | */ | |
5524 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5525 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
5526 | ||
1da177e4 LT |
5527 | disposition = SCTP_DISPOSITION_CONSUME; |
5528 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
5529 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
5530 | arg, commands); | |
5531 | } | |
5532 | return disposition; | |
5533 | } | |
5534 | ||
5535 | /***************************************************************************** | |
5536 | * These are sa state functions which could apply to all types of events. | |
5537 | ****************************************************************************/ | |
5538 | ||
5539 | /* | |
5540 | * This table entry is not implemented. | |
5541 | * | |
5542 | * Inputs | |
5543 | * (endpoint, asoc, chunk) | |
5544 | * | |
5545 | * The return value is the disposition of the chunk. | |
5546 | */ | |
5547 | sctp_disposition_t sctp_sf_not_impl(const struct sctp_endpoint *ep, | |
5548 | const struct sctp_association *asoc, | |
5549 | const sctp_subtype_t type, | |
5550 | void *arg, | |
5551 | sctp_cmd_seq_t *commands) | |
5552 | { | |
5553 | return SCTP_DISPOSITION_NOT_IMPL; | |
5554 | } | |
5555 | ||
5556 | /* | |
5557 | * This table entry represents a bug. | |
5558 | * | |
5559 | * Inputs | |
5560 | * (endpoint, asoc, chunk) | |
5561 | * | |
5562 | * The return value is the disposition of the chunk. | |
5563 | */ | |
5564 | sctp_disposition_t sctp_sf_bug(const struct sctp_endpoint *ep, | |
5565 | const struct sctp_association *asoc, | |
5566 | const sctp_subtype_t type, | |
5567 | void *arg, | |
5568 | sctp_cmd_seq_t *commands) | |
5569 | { | |
5570 | return SCTP_DISPOSITION_BUG; | |
5571 | } | |
5572 | ||
5573 | /* | |
5574 | * This table entry represents the firing of a timer in the wrong state. | |
5575 | * Since timer deletion cannot be guaranteed a timer 'may' end up firing | |
5576 | * when the association is in the wrong state. This event should | |
5577 | * be ignored, so as to prevent any rearming of the timer. | |
5578 | * | |
5579 | * Inputs | |
5580 | * (endpoint, asoc, chunk) | |
5581 | * | |
5582 | * The return value is the disposition of the chunk. | |
5583 | */ | |
5584 | sctp_disposition_t sctp_sf_timer_ignore(const struct sctp_endpoint *ep, | |
5585 | const struct sctp_association *asoc, | |
5586 | const sctp_subtype_t type, | |
5587 | void *arg, | |
5588 | sctp_cmd_seq_t *commands) | |
5589 | { | |
5590 | SCTP_DEBUG_PRINTK("Timer %d ignored.\n", type.chunk); | |
5591 | return SCTP_DISPOSITION_CONSUME; | |
5592 | } | |
5593 | ||
5594 | /******************************************************************** | |
5595 | * 2nd Level Abstractions | |
5596 | ********************************************************************/ | |
5597 | ||
5598 | /* Pull the SACK chunk based on the SACK header. */ | |
5599 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk) | |
5600 | { | |
5601 | struct sctp_sackhdr *sack; | |
5602 | unsigned int len; | |
5603 | __u16 num_blocks; | |
5604 | __u16 num_dup_tsns; | |
5605 | ||
5606 | /* Protect ourselves from reading too far into | |
5607 | * the skb from a bogus sender. | |
5608 | */ | |
5609 | sack = (struct sctp_sackhdr *) chunk->skb->data; | |
5610 | ||
5611 | num_blocks = ntohs(sack->num_gap_ack_blocks); | |
5612 | num_dup_tsns = ntohs(sack->num_dup_tsns); | |
5613 | len = sizeof(struct sctp_sackhdr); | |
5614 | len += (num_blocks + num_dup_tsns) * sizeof(__u32); | |
5615 | if (len > chunk->skb->len) | |
5616 | return NULL; | |
5617 | ||
5618 | skb_pull(chunk->skb, len); | |
5619 | ||
5620 | return sack; | |
5621 | } | |
5622 | ||
5623 | /* Create an ABORT packet to be sent as a response, with the specified | |
5624 | * error causes. | |
5625 | */ | |
5626 | static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep, | |
5627 | const struct sctp_association *asoc, | |
5628 | struct sctp_chunk *chunk, | |
5629 | const void *payload, | |
5630 | size_t paylen) | |
5631 | { | |
5632 | struct sctp_packet *packet; | |
5633 | struct sctp_chunk *abort; | |
5634 | ||
5635 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5636 | ||
5637 | if (packet) { | |
5638 | /* Make an ABORT. | |
5639 | * The T bit will be set if the asoc is NULL. | |
5640 | */ | |
5641 | abort = sctp_make_abort(asoc, chunk, paylen); | |
5642 | if (!abort) { | |
5643 | sctp_ootb_pkt_free(packet); | |
5644 | return NULL; | |
5645 | } | |
047a2428 JF |
5646 | |
5647 | /* Reflect vtag if T-Bit is set */ | |
5648 | if (sctp_test_T_bit(abort)) | |
5649 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
5650 | ||
1da177e4 LT |
5651 | /* Add specified error causes, i.e., payload, to the |
5652 | * end of the chunk. | |
5653 | */ | |
5654 | sctp_addto_chunk(abort, paylen, payload); | |
5655 | ||
5656 | /* Set the skb to the belonging sock for accounting. */ | |
5657 | abort->skb->sk = ep->base.sk; | |
5658 | ||
5659 | sctp_packet_append_chunk(packet, abort); | |
5660 | ||
5661 | } | |
5662 | ||
5663 | return packet; | |
5664 | } | |
5665 | ||
5666 | /* Allocate a packet for responding in the OOTB conditions. */ | |
5667 | static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc, | |
5668 | const struct sctp_chunk *chunk) | |
5669 | { | |
5670 | struct sctp_packet *packet; | |
5671 | struct sctp_transport *transport; | |
5672 | __u16 sport; | |
5673 | __u16 dport; | |
5674 | __u32 vtag; | |
5675 | ||
5676 | /* Get the source and destination port from the inbound packet. */ | |
5677 | sport = ntohs(chunk->sctp_hdr->dest); | |
5678 | dport = ntohs(chunk->sctp_hdr->source); | |
5679 | ||
5680 | /* The V-tag is going to be the same as the inbound packet if no | |
5681 | * association exists, otherwise, use the peer's vtag. | |
5682 | */ | |
5683 | if (asoc) { | |
02c4e12c WY |
5684 | /* Special case the INIT-ACK as there is no peer's vtag |
5685 | * yet. | |
5686 | */ | |
5687 | switch(chunk->chunk_hdr->type) { | |
5688 | case SCTP_CID_INIT_ACK: | |
5689 | { | |
5690 | sctp_initack_chunk_t *initack; | |
5691 | ||
5692 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
5693 | vtag = ntohl(initack->init_hdr.init_tag); | |
5694 | break; | |
5695 | } | |
5696 | default: | |
5697 | vtag = asoc->peer.i.init_tag; | |
5698 | break; | |
5699 | } | |
1da177e4 LT |
5700 | } else { |
5701 | /* Special case the INIT and stale COOKIE_ECHO as there is no | |
5702 | * vtag yet. | |
5703 | */ | |
5704 | switch(chunk->chunk_hdr->type) { | |
5705 | case SCTP_CID_INIT: | |
5706 | { | |
5707 | sctp_init_chunk_t *init; | |
5708 | ||
5709 | init = (sctp_init_chunk_t *)chunk->chunk_hdr; | |
5710 | vtag = ntohl(init->init_hdr.init_tag); | |
5711 | break; | |
5712 | } | |
d808ad9a | 5713 | default: |
1da177e4 LT |
5714 | vtag = ntohl(chunk->sctp_hdr->vtag); |
5715 | break; | |
5716 | } | |
5717 | } | |
5718 | ||
5719 | /* Make a transport for the bucket, Eliza... */ | |
6a1e5f33 | 5720 | transport = sctp_transport_new(sctp_source(chunk), GFP_ATOMIC); |
1da177e4 LT |
5721 | if (!transport) |
5722 | goto nomem; | |
5723 | ||
5724 | /* Cache a route for the transport with the chunk's destination as | |
5725 | * the source address. | |
5726 | */ | |
16b0a030 | 5727 | sctp_transport_route(transport, (union sctp_addr *)&chunk->dest, |
1da177e4 LT |
5728 | sctp_sk(sctp_get_ctl_sock())); |
5729 | ||
5730 | packet = sctp_packet_init(&transport->packet, transport, sport, dport); | |
5731 | packet = sctp_packet_config(packet, vtag, 0); | |
5732 | ||
5733 | return packet; | |
5734 | ||
5735 | nomem: | |
5736 | return NULL; | |
5737 | } | |
5738 | ||
5739 | /* Free the packet allocated earlier for responding in the OOTB condition. */ | |
5740 | void sctp_ootb_pkt_free(struct sctp_packet *packet) | |
5741 | { | |
5742 | sctp_transport_free(packet->transport); | |
5743 | } | |
5744 | ||
5745 | /* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */ | |
5746 | static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep, | |
5747 | const struct sctp_association *asoc, | |
5748 | const struct sctp_chunk *chunk, | |
5749 | sctp_cmd_seq_t *commands, | |
5750 | struct sctp_chunk *err_chunk) | |
5751 | { | |
5752 | struct sctp_packet *packet; | |
5753 | ||
5754 | if (err_chunk) { | |
5755 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5756 | if (packet) { | |
5757 | struct sctp_signed_cookie *cookie; | |
5758 | ||
5759 | /* Override the OOTB vtag from the cookie. */ | |
5760 | cookie = chunk->subh.cookie_hdr; | |
5761 | packet->vtag = cookie->c.peer_vtag; | |
d808ad9a | 5762 | |
1da177e4 LT |
5763 | /* Set the skb to the belonging sock for accounting. */ |
5764 | err_chunk->skb->sk = ep->base.sk; | |
5765 | sctp_packet_append_chunk(packet, err_chunk); | |
5766 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
5767 | SCTP_PACKET(packet)); | |
5768 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
5769 | } else | |
5770 | sctp_chunk_free (err_chunk); | |
5771 | } | |
5772 | } | |
5773 | ||
5774 | ||
5775 | /* Process a data chunk */ | |
5776 | static int sctp_eat_data(const struct sctp_association *asoc, | |
5777 | struct sctp_chunk *chunk, | |
5778 | sctp_cmd_seq_t *commands) | |
5779 | { | |
5780 | sctp_datahdr_t *data_hdr; | |
5781 | struct sctp_chunk *err; | |
5782 | size_t datalen; | |
5783 | sctp_verb_t deliver; | |
5784 | int tmp; | |
5785 | __u32 tsn; | |
7c3ceb4f | 5786 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
049b3ff5 | 5787 | struct sock *sk = asoc->base.sk; |
1da177e4 LT |
5788 | |
5789 | data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data; | |
5790 | skb_pull(chunk->skb, sizeof(sctp_datahdr_t)); | |
5791 | ||
5792 | tsn = ntohl(data_hdr->tsn); | |
5793 | SCTP_DEBUG_PRINTK("eat_data: TSN 0x%x.\n", tsn); | |
5794 | ||
5795 | /* ASSERT: Now skb->data is really the user data. */ | |
5796 | ||
5797 | /* Process ECN based congestion. | |
5798 | * | |
5799 | * Since the chunk structure is reused for all chunks within | |
5800 | * a packet, we use ecn_ce_done to track if we've already | |
5801 | * done CE processing for this packet. | |
5802 | * | |
5803 | * We need to do ECN processing even if we plan to discard the | |
5804 | * chunk later. | |
5805 | */ | |
5806 | ||
5807 | if (!chunk->ecn_ce_done) { | |
5808 | struct sctp_af *af; | |
5809 | chunk->ecn_ce_done = 1; | |
5810 | ||
5811 | af = sctp_get_af_specific( | |
eddc9ec5 | 5812 | ipver2af(ip_hdr(chunk->skb)->version)); |
1da177e4 LT |
5813 | |
5814 | if (af && af->is_ce(chunk->skb) && asoc->peer.ecn_capable) { | |
5815 | /* Do real work as sideffect. */ | |
5816 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE, | |
5817 | SCTP_U32(tsn)); | |
5818 | } | |
5819 | } | |
5820 | ||
5821 | tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn); | |
5822 | if (tmp < 0) { | |
5823 | /* The TSN is too high--silently discard the chunk and | |
5824 | * count on it getting retransmitted later. | |
5825 | */ | |
5826 | return SCTP_IERROR_HIGH_TSN; | |
5827 | } else if (tmp > 0) { | |
5828 | /* This is a duplicate. Record it. */ | |
5829 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn)); | |
5830 | return SCTP_IERROR_DUP_TSN; | |
5831 | } | |
5832 | ||
5833 | /* This is a new TSN. */ | |
5834 | ||
5835 | /* Discard if there is no room in the receive window. | |
5836 | * Actually, allow a little bit of overflow (up to a MTU). | |
5837 | */ | |
5838 | datalen = ntohs(chunk->chunk_hdr->length); | |
5839 | datalen -= sizeof(sctp_data_chunk_t); | |
5840 | ||
5841 | deliver = SCTP_CMD_CHUNK_ULP; | |
5842 | ||
5843 | /* Think about partial delivery. */ | |
5844 | if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) { | |
5845 | ||
5846 | /* Even if we don't accept this chunk there is | |
5847 | * memory pressure. | |
5848 | */ | |
5849 | sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL()); | |
5850 | } | |
5851 | ||
d808ad9a | 5852 | /* Spill over rwnd a little bit. Note: While allowed, this spill over |
1da177e4 LT |
5853 | * seems a bit troublesome in that frag_point varies based on |
5854 | * PMTU. In cases, such as loopback, this might be a rather | |
5855 | * large spill over. | |
4d93df0a NH |
5856 | */ |
5857 | if ((!chunk->data_accepted) && (!asoc->rwnd || asoc->rwnd_over || | |
5858 | (datalen > asoc->rwnd + asoc->frag_point))) { | |
1da177e4 LT |
5859 | |
5860 | /* If this is the next TSN, consider reneging to make | |
5861 | * room. Note: Playing nice with a confused sender. A | |
5862 | * malicious sender can still eat up all our buffer | |
5863 | * space and in the future we may want to detect and | |
5864 | * do more drastic reneging. | |
5865 | */ | |
7c3ceb4f NH |
5866 | if (sctp_tsnmap_has_gap(map) && |
5867 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
1da177e4 LT |
5868 | SCTP_DEBUG_PRINTK("Reneging for tsn:%u\n", tsn); |
5869 | deliver = SCTP_CMD_RENEGE; | |
5870 | } else { | |
5871 | SCTP_DEBUG_PRINTK("Discard tsn: %u len: %Zd, " | |
5872 | "rwnd: %d\n", tsn, datalen, | |
5873 | asoc->rwnd); | |
5874 | return SCTP_IERROR_IGNORE_TSN; | |
5875 | } | |
5876 | } | |
5877 | ||
4d93df0a NH |
5878 | /* |
5879 | * Also try to renege to limit our memory usage in the event that | |
5880 | * we are under memory pressure | |
3ab224be | 5881 | * If we can't renege, don't worry about it, the sk_rmem_schedule |
4d93df0a NH |
5882 | * in sctp_ulpevent_make_rcvmsg will drop the frame if we grow our |
5883 | * memory usage too much | |
5884 | */ | |
5885 | if (*sk->sk_prot_creator->memory_pressure) { | |
5886 | if (sctp_tsnmap_has_gap(map) && | |
5887 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
5888 | SCTP_DEBUG_PRINTK("Under Pressure! Reneging for tsn:%u\n", tsn); | |
5889 | deliver = SCTP_CMD_RENEGE; | |
5890 | } | |
5891 | } | |
5892 | ||
1da177e4 LT |
5893 | /* |
5894 | * Section 3.3.10.9 No User Data (9) | |
5895 | * | |
5896 | * Cause of error | |
5897 | * --------------- | |
5898 | * No User Data: This error cause is returned to the originator of a | |
5899 | * DATA chunk if a received DATA chunk has no user data. | |
5900 | */ | |
5901 | if (unlikely(0 == datalen)) { | |
5902 | err = sctp_make_abort_no_data(asoc, chunk, tsn); | |
5903 | if (err) { | |
5904 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5905 | SCTP_CHUNK(err)); | |
5906 | } | |
5907 | /* We are going to ABORT, so we might as well stop | |
5908 | * processing the rest of the chunks in the packet. | |
5909 | */ | |
5910 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 SS |
5911 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5912 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 | 5913 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5914 | SCTP_PERR(SCTP_ERROR_NO_DATA)); |
1da177e4 LT |
5915 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5916 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5917 | return SCTP_IERROR_NO_DATA; | |
5918 | } | |
5919 | ||
9faa730f SS |
5920 | chunk->data_accepted = 1; |
5921 | ||
1da177e4 LT |
5922 | /* Note: Some chunks may get overcounted (if we drop) or overcounted |
5923 | * if we renege and the chunk arrives again. | |
5924 | */ | |
5925 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) | |
5926 | SCTP_INC_STATS(SCTP_MIB_INUNORDERCHUNKS); | |
5927 | else | |
5928 | SCTP_INC_STATS(SCTP_MIB_INORDERCHUNKS); | |
5929 | ||
5930 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
5931 | * | |
5932 | * If an endpoint receive a DATA chunk with an invalid stream | |
5933 | * identifier, it shall acknowledge the reception of the DATA chunk | |
5934 | * following the normal procedure, immediately send an ERROR chunk | |
5935 | * with cause set to "Invalid Stream Identifier" (See Section 3.3.10) | |
5936 | * and discard the DATA chunk. | |
5937 | */ | |
5938 | if (ntohs(data_hdr->stream) >= asoc->c.sinit_max_instreams) { | |
3888e9ef VY |
5939 | /* Mark tsn as received even though we drop it */ |
5940 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn)); | |
5941 | ||
1da177e4 LT |
5942 | err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM, |
5943 | &data_hdr->stream, | |
5944 | sizeof(data_hdr->stream)); | |
5945 | if (err) | |
5946 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5947 | SCTP_CHUNK(err)); | |
5948 | return SCTP_IERROR_BAD_STREAM; | |
5949 | } | |
5950 | ||
5951 | /* Send the data up to the user. Note: Schedule the | |
5952 | * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK | |
5953 | * chunk needs the updated rwnd. | |
5954 | */ | |
5955 | sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk)); | |
5956 | ||
5957 | return SCTP_IERROR_NO_ERROR; | |
5958 | } |