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1da177e4 LT |
1 | /* SCTP kernel reference Implementation |
2 | * (C) Copyright IBM Corp. 2001, 2004 | |
3 | * Copyright (c) 1999-2000 Cisco, Inc. | |
4 | * Copyright (c) 1999-2001 Motorola, Inc. | |
5 | * Copyright (c) 2001-2002 Intel Corp. | |
6 | * Copyright (c) 2002 Nokia Corp. | |
7 | * | |
8 | * This file is part of the SCTP kernel reference Implementation | |
9 | * | |
10 | * This is part of the SCTP Linux Kernel Reference Implementation. | |
11 | * | |
12 | * These are the state functions for the state machine. | |
13 | * | |
14 | * The SCTP reference implementation is free software; | |
15 | * you can redistribute it and/or modify it under the terms of | |
16 | * the GNU General Public License as published by | |
17 | * the Free Software Foundation; either version 2, or (at your option) | |
18 | * any later version. | |
19 | * | |
20 | * The SCTP reference implementation is distributed in the hope that it | |
21 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied | |
22 | * ************************ | |
23 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | |
24 | * See the GNU General Public License for more details. | |
25 | * | |
26 | * You should have received a copy of the GNU General Public License | |
27 | * along with GNU CC; see the file COPYING. If not, write to | |
28 | * the Free Software Foundation, 59 Temple Place - Suite 330, | |
29 | * Boston, MA 02111-1307, USA. | |
30 | * | |
31 | * Please send any bug reports or fixes you make to the | |
32 | * email address(es): | |
33 | * lksctp developers <lksctp-developers@lists.sourceforge.net> | |
34 | * | |
35 | * Or submit a bug report through the following website: | |
36 | * http://www.sf.net/projects/lksctp | |
37 | * | |
38 | * Written or modified by: | |
39 | * La Monte H.P. Yarroll <piggy@acm.org> | |
40 | * Karl Knutson <karl@athena.chicago.il.us> | |
41 | * Mathew Kotowsky <kotowsky@sctp.org> | |
42 | * Sridhar Samudrala <samudrala@us.ibm.com> | |
43 | * Jon Grimm <jgrimm@us.ibm.com> | |
44 | * Hui Huang <hui.huang@nokia.com> | |
45 | * Dajiang Zhang <dajiang.zhang@nokia.com> | |
46 | * Daisy Chang <daisyc@us.ibm.com> | |
47 | * Ardelle Fan <ardelle.fan@intel.com> | |
48 | * Ryan Layer <rmlayer@us.ibm.com> | |
49 | * Kevin Gao <kevin.gao@intel.com> | |
50 | * | |
51 | * Any bugs reported given to us we will try to fix... any fixes shared will | |
52 | * be incorporated into the next SCTP release. | |
53 | */ | |
54 | ||
55 | #include <linux/types.h> | |
56 | #include <linux/kernel.h> | |
57 | #include <linux/ip.h> | |
58 | #include <linux/ipv6.h> | |
59 | #include <linux/net.h> | |
60 | #include <linux/inet.h> | |
61 | #include <net/sock.h> | |
62 | #include <net/inet_ecn.h> | |
63 | #include <linux/skbuff.h> | |
64 | #include <net/sctp/sctp.h> | |
65 | #include <net/sctp/sm.h> | |
66 | #include <net/sctp/structs.h> | |
67 | ||
68 | static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep, | |
69 | const struct sctp_association *asoc, | |
70 | struct sctp_chunk *chunk, | |
71 | const void *payload, | |
72 | size_t paylen); | |
73 | static int sctp_eat_data(const struct sctp_association *asoc, | |
74 | struct sctp_chunk *chunk, | |
75 | sctp_cmd_seq_t *commands); | |
76 | static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc, | |
77 | const struct sctp_chunk *chunk); | |
78 | static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep, | |
79 | const struct sctp_association *asoc, | |
80 | const struct sctp_chunk *chunk, | |
81 | sctp_cmd_seq_t *commands, | |
82 | struct sctp_chunk *err_chunk); | |
83 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, | |
84 | const struct sctp_association *asoc, | |
85 | const sctp_subtype_t type, | |
86 | void *arg, | |
87 | sctp_cmd_seq_t *commands); | |
88 | static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, | |
89 | const struct sctp_association *asoc, | |
90 | const sctp_subtype_t type, | |
91 | void *arg, | |
92 | sctp_cmd_seq_t *commands); | |
ece25dfa VY |
93 | static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, |
94 | const struct sctp_association *asoc, | |
95 | const sctp_subtype_t type, | |
96 | void *arg, | |
97 | sctp_cmd_seq_t *commands); | |
1da177e4 LT |
98 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk); |
99 | ||
52c1da39 | 100 | static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, |
f94c0198 | 101 | __be16 error, int sk_err, |
52c1da39 AB |
102 | const struct sctp_association *asoc, |
103 | struct sctp_transport *transport); | |
104 | ||
aecedeab | 105 | static sctp_disposition_t sctp_sf_abort_violation( |
ece25dfa | 106 | const struct sctp_endpoint *ep, |
aecedeab WY |
107 | const struct sctp_association *asoc, |
108 | void *arg, | |
109 | sctp_cmd_seq_t *commands, | |
110 | const __u8 *payload, | |
111 | const size_t paylen); | |
112 | ||
52c1da39 AB |
113 | static sctp_disposition_t sctp_sf_violation_chunklen( |
114 | const struct sctp_endpoint *ep, | |
115 | const struct sctp_association *asoc, | |
116 | const sctp_subtype_t type, | |
117 | void *arg, | |
118 | sctp_cmd_seq_t *commands); | |
1da177e4 | 119 | |
aecedeab WY |
120 | static sctp_disposition_t sctp_sf_violation_ctsn( |
121 | const struct sctp_endpoint *ep, | |
122 | const struct sctp_association *asoc, | |
123 | const sctp_subtype_t type, | |
124 | void *arg, | |
125 | sctp_cmd_seq_t *commands); | |
126 | ||
ece25dfa VY |
127 | static sctp_disposition_t sctp_sf_violation_chunk( |
128 | const struct sctp_endpoint *ep, | |
129 | const struct sctp_association *asoc, | |
130 | const sctp_subtype_t type, | |
131 | void *arg, | |
132 | sctp_cmd_seq_t *commands); | |
133 | ||
1da177e4 LT |
134 | /* Small helper function that checks if the chunk length |
135 | * is of the appropriate length. The 'required_length' argument | |
136 | * is set to be the size of a specific chunk we are testing. | |
137 | * Return Values: 1 = Valid length | |
138 | * 0 = Invalid length | |
139 | * | |
140 | */ | |
141 | static inline int | |
142 | sctp_chunk_length_valid(struct sctp_chunk *chunk, | |
143 | __u16 required_length) | |
144 | { | |
145 | __u16 chunk_length = ntohs(chunk->chunk_hdr->length); | |
146 | ||
147 | if (unlikely(chunk_length < required_length)) | |
148 | return 0; | |
149 | ||
150 | return 1; | |
151 | } | |
152 | ||
153 | /********************************************************** | |
154 | * These are the state functions for handling chunk events. | |
155 | **********************************************************/ | |
156 | ||
157 | /* | |
158 | * Process the final SHUTDOWN COMPLETE. | |
159 | * | |
160 | * Section: 4 (C) (diagram), 9.2 | |
161 | * Upon reception of the SHUTDOWN COMPLETE chunk the endpoint will verify | |
162 | * that it is in SHUTDOWN-ACK-SENT state, if it is not the chunk should be | |
163 | * discarded. If the endpoint is in the SHUTDOWN-ACK-SENT state the endpoint | |
164 | * should stop the T2-shutdown timer and remove all knowledge of the | |
165 | * association (and thus the association enters the CLOSED state). | |
166 | * | |
047a2428 | 167 | * Verification Tag: 8.5.1(C), sctpimpguide 2.41. |
1da177e4 LT |
168 | * C) Rules for packet carrying SHUTDOWN COMPLETE: |
169 | * ... | |
047a2428 JF |
170 | * - The receiver of a SHUTDOWN COMPLETE shall accept the packet |
171 | * if the Verification Tag field of the packet matches its own tag and | |
172 | * the T bit is not set | |
173 | * OR | |
174 | * it is set to its peer's tag and the T bit is set in the Chunk | |
175 | * Flags. | |
176 | * Otherwise, the receiver MUST silently discard the packet | |
177 | * and take no further action. An endpoint MUST ignore the | |
178 | * SHUTDOWN COMPLETE if it is not in the SHUTDOWN-ACK-SENT state. | |
1da177e4 LT |
179 | * |
180 | * Inputs | |
181 | * (endpoint, asoc, chunk) | |
182 | * | |
183 | * Outputs | |
184 | * (asoc, reply_msg, msg_up, timers, counters) | |
185 | * | |
186 | * The return value is the disposition of the chunk. | |
187 | */ | |
188 | sctp_disposition_t sctp_sf_do_4_C(const struct sctp_endpoint *ep, | |
189 | const struct sctp_association *asoc, | |
190 | const sctp_subtype_t type, | |
191 | void *arg, | |
192 | sctp_cmd_seq_t *commands) | |
193 | { | |
194 | struct sctp_chunk *chunk = arg; | |
195 | struct sctp_ulpevent *ev; | |
196 | ||
ece25dfa VY |
197 | if (!sctp_vtag_verify_either(chunk, asoc)) |
198 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
199 | ||
1da177e4 LT |
200 | /* RFC 2960 6.10 Bundling |
201 | * | |
202 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
203 | * SHUTDOWN COMPLETE with any other chunks. | |
204 | */ | |
205 | if (!chunk->singleton) | |
ece25dfa | 206 | return sctp_sf_violation_chunk(ep, asoc, type, arg, commands); |
1da177e4 | 207 | |
ece25dfa VY |
208 | /* Make sure that the SHUTDOWN_COMPLETE chunk has a valid length. */ |
209 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
210 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
211 | commands); | |
1da177e4 LT |
212 | |
213 | /* RFC 2960 10.2 SCTP-to-ULP | |
214 | * | |
215 | * H) SHUTDOWN COMPLETE notification | |
216 | * | |
217 | * When SCTP completes the shutdown procedures (section 9.2) this | |
218 | * notification is passed to the upper layer. | |
219 | */ | |
220 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 221 | 0, 0, 0, NULL, GFP_ATOMIC); |
df7deeb5 VY |
222 | if (ev) |
223 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
d808ad9a | 224 | SCTP_ULPEVENT(ev)); |
1da177e4 LT |
225 | |
226 | /* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint | |
227 | * will verify that it is in SHUTDOWN-ACK-SENT state, if it is | |
228 | * not the chunk should be discarded. If the endpoint is in | |
229 | * the SHUTDOWN-ACK-SENT state the endpoint should stop the | |
230 | * T2-shutdown timer and remove all knowledge of the | |
231 | * association (and thus the association enters the CLOSED | |
232 | * state). | |
233 | */ | |
234 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
235 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
236 | ||
237 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
238 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
239 | ||
240 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
241 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
242 | ||
243 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
244 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
245 | ||
246 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
247 | ||
248 | return SCTP_DISPOSITION_DELETE_TCB; | |
1da177e4 LT |
249 | } |
250 | ||
251 | /* | |
252 | * Respond to a normal INIT chunk. | |
253 | * We are the side that is being asked for an association. | |
254 | * | |
255 | * Section: 5.1 Normal Establishment of an Association, B | |
256 | * B) "Z" shall respond immediately with an INIT ACK chunk. The | |
257 | * destination IP address of the INIT ACK MUST be set to the source | |
258 | * IP address of the INIT to which this INIT ACK is responding. In | |
259 | * the response, besides filling in other parameters, "Z" must set the | |
260 | * Verification Tag field to Tag_A, and also provide its own | |
261 | * Verification Tag (Tag_Z) in the Initiate Tag field. | |
262 | * | |
d808ad9a | 263 | * Verification Tag: Must be 0. |
1da177e4 LT |
264 | * |
265 | * Inputs | |
266 | * (endpoint, asoc, chunk) | |
267 | * | |
268 | * Outputs | |
269 | * (asoc, reply_msg, msg_up, timers, counters) | |
270 | * | |
271 | * The return value is the disposition of the chunk. | |
272 | */ | |
273 | sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep, | |
274 | const struct sctp_association *asoc, | |
275 | const sctp_subtype_t type, | |
276 | void *arg, | |
277 | sctp_cmd_seq_t *commands) | |
278 | { | |
279 | struct sctp_chunk *chunk = arg; | |
280 | struct sctp_chunk *repl; | |
281 | struct sctp_association *new_asoc; | |
282 | struct sctp_chunk *err_chunk; | |
283 | struct sctp_packet *packet; | |
284 | sctp_unrecognized_param_t *unk_param; | |
1da177e4 LT |
285 | int len; |
286 | ||
287 | /* 6.10 Bundling | |
288 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
289 | * SHUTDOWN COMPLETE with any other chunks. | |
d808ad9a | 290 | * |
1da177e4 LT |
291 | * IG Section 2.11.2 |
292 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
293 | * enforce these rules by silently discarding an arriving packet | |
294 | * with an INIT chunk that is bundled with other chunks. | |
295 | */ | |
296 | if (!chunk->singleton) | |
297 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
298 | ||
299 | /* If the packet is an OOTB packet which is temporarily on the | |
300 | * control endpoint, respond with an ABORT. | |
301 | */ | |
302 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) | |
303 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
304 | ||
1da177e4 | 305 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification |
d808ad9a | 306 | * Tag. |
1da177e4 LT |
307 | */ |
308 | if (chunk->sctp_hdr->vtag != 0) | |
309 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
310 | ||
311 | /* Make sure that the INIT chunk has a valid length. | |
312 | * Normally, this would cause an ABORT with a Protocol Violation | |
313 | * error, but since we don't have an association, we'll | |
314 | * just discard the packet. | |
315 | */ | |
316 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
317 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
318 | ||
319 | /* Verify the INIT chunk before processing it. */ | |
320 | err_chunk = NULL; | |
321 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
322 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
323 | &err_chunk)) { | |
324 | /* This chunk contains fatal error. It is to be discarded. | |
325 | * Send an ABORT, with causes if there is any. | |
326 | */ | |
327 | if (err_chunk) { | |
328 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
329 | (__u8 *)(err_chunk->chunk_hdr) + | |
330 | sizeof(sctp_chunkhdr_t), | |
331 | ntohs(err_chunk->chunk_hdr->length) - | |
332 | sizeof(sctp_chunkhdr_t)); | |
333 | ||
334 | sctp_chunk_free(err_chunk); | |
335 | ||
336 | if (packet) { | |
337 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
338 | SCTP_PACKET(packet)); | |
339 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
340 | return SCTP_DISPOSITION_CONSUME; | |
341 | } else { | |
342 | return SCTP_DISPOSITION_NOMEM; | |
343 | } | |
344 | } else { | |
345 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
346 | commands); | |
347 | } | |
348 | } | |
349 | ||
d808ad9a | 350 | /* Grab the INIT header. */ |
1da177e4 LT |
351 | chunk->subh.init_hdr = (sctp_inithdr_t *)chunk->skb->data; |
352 | ||
353 | /* Tag the variable length parameters. */ | |
354 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
355 | ||
356 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
357 | if (!new_asoc) | |
358 | goto nomem; | |
359 | ||
360 | /* The call, sctp_process_init(), can fail on memory allocation. */ | |
361 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
362 | sctp_source(chunk), | |
363 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
364 | GFP_ATOMIC)) | |
365 | goto nomem_init; | |
366 | ||
1da177e4 LT |
367 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ |
368 | ||
369 | /* If there are errors need to be reported for unknown parameters, | |
370 | * make sure to reserve enough room in the INIT ACK for them. | |
371 | */ | |
372 | len = 0; | |
373 | if (err_chunk) | |
374 | len = ntohs(err_chunk->chunk_hdr->length) - | |
375 | sizeof(sctp_chunkhdr_t); | |
376 | ||
377 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0) | |
df7deeb5 | 378 | goto nomem_init; |
1da177e4 LT |
379 | |
380 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); | |
381 | if (!repl) | |
df7deeb5 | 382 | goto nomem_init; |
1da177e4 LT |
383 | |
384 | /* If there are errors need to be reported for unknown parameters, | |
385 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
386 | * parameter. | |
387 | */ | |
388 | if (err_chunk) { | |
389 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
390 | * ERROR chunk generated by sctp_verify_init(). Since the | |
391 | * error cause code for "unknown parameter" and the | |
392 | * "Unrecognized parameter" type is the same, we can | |
393 | * construct the parameters in INIT ACK by copying the | |
394 | * ERROR causes over. | |
395 | */ | |
396 | unk_param = (sctp_unrecognized_param_t *) | |
397 | ((__u8 *)(err_chunk->chunk_hdr) + | |
398 | sizeof(sctp_chunkhdr_t)); | |
399 | /* Replace the cause code with the "Unrecognized parameter" | |
400 | * parameter type. | |
401 | */ | |
402 | sctp_addto_chunk(repl, len, unk_param); | |
403 | sctp_chunk_free(err_chunk); | |
404 | } | |
405 | ||
df7deeb5 VY |
406 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); |
407 | ||
1da177e4 LT |
408 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
409 | ||
410 | /* | |
411 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
412 | * "Z" MUST NOT allocate any resources, nor keep any states for the | |
413 | * new association. Otherwise, "Z" will be vulnerable to resource | |
414 | * attacks. | |
415 | */ | |
416 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
417 | ||
418 | return SCTP_DISPOSITION_DELETE_TCB; | |
419 | ||
1da177e4 LT |
420 | nomem_init: |
421 | sctp_association_free(new_asoc); | |
422 | nomem: | |
df7deeb5 VY |
423 | if (err_chunk) |
424 | sctp_chunk_free(err_chunk); | |
1da177e4 LT |
425 | return SCTP_DISPOSITION_NOMEM; |
426 | } | |
427 | ||
428 | /* | |
429 | * Respond to a normal INIT ACK chunk. | |
430 | * We are the side that is initiating the association. | |
431 | * | |
432 | * Section: 5.1 Normal Establishment of an Association, C | |
433 | * C) Upon reception of the INIT ACK from "Z", "A" shall stop the T1-init | |
434 | * timer and leave COOKIE-WAIT state. "A" shall then send the State | |
435 | * Cookie received in the INIT ACK chunk in a COOKIE ECHO chunk, start | |
436 | * the T1-cookie timer, and enter the COOKIE-ECHOED state. | |
437 | * | |
438 | * Note: The COOKIE ECHO chunk can be bundled with any pending outbound | |
439 | * DATA chunks, but it MUST be the first chunk in the packet and | |
440 | * until the COOKIE ACK is returned the sender MUST NOT send any | |
441 | * other packets to the peer. | |
442 | * | |
443 | * Verification Tag: 3.3.3 | |
444 | * If the value of the Initiate Tag in a received INIT ACK chunk is | |
445 | * found to be 0, the receiver MUST treat it as an error and close the | |
446 | * association by transmitting an ABORT. | |
447 | * | |
448 | * Inputs | |
449 | * (endpoint, asoc, chunk) | |
450 | * | |
451 | * Outputs | |
452 | * (asoc, reply_msg, msg_up, timers, counters) | |
453 | * | |
454 | * The return value is the disposition of the chunk. | |
455 | */ | |
456 | sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep, | |
457 | const struct sctp_association *asoc, | |
458 | const sctp_subtype_t type, | |
459 | void *arg, | |
460 | sctp_cmd_seq_t *commands) | |
461 | { | |
462 | struct sctp_chunk *chunk = arg; | |
463 | sctp_init_chunk_t *initchunk; | |
1da177e4 LT |
464 | struct sctp_chunk *err_chunk; |
465 | struct sctp_packet *packet; | |
f94c0198 | 466 | sctp_error_t error; |
1da177e4 LT |
467 | |
468 | if (!sctp_vtag_verify(chunk, asoc)) | |
469 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
470 | ||
1da177e4 LT |
471 | /* 6.10 Bundling |
472 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
473 | * SHUTDOWN COMPLETE with any other chunks. | |
474 | */ | |
475 | if (!chunk->singleton) | |
ece25dfa | 476 | return sctp_sf_violation_chunk(ep, asoc, type, arg, commands); |
1da177e4 | 477 | |
ece25dfa VY |
478 | /* Make sure that the INIT-ACK chunk has a valid length */ |
479 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_initack_chunk_t))) | |
480 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
481 | commands); | |
1da177e4 LT |
482 | /* Grab the INIT header. */ |
483 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
484 | ||
1da177e4 LT |
485 | /* Verify the INIT chunk before processing it. */ |
486 | err_chunk = NULL; | |
487 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
488 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
489 | &err_chunk)) { | |
490 | ||
491 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
492 | ||
493 | /* This chunk contains fatal error. It is to be discarded. | |
494 | * Send an ABORT, with causes if there is any. | |
495 | */ | |
496 | if (err_chunk) { | |
497 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
498 | (__u8 *)(err_chunk->chunk_hdr) + | |
499 | sizeof(sctp_chunkhdr_t), | |
500 | ntohs(err_chunk->chunk_hdr->length) - | |
501 | sizeof(sctp_chunkhdr_t)); | |
502 | ||
503 | sctp_chunk_free(err_chunk); | |
504 | ||
505 | if (packet) { | |
506 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
507 | SCTP_PACKET(packet)); | |
508 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
8de8c873 | 509 | error = SCTP_ERROR_INV_PARAM; |
1da177e4 | 510 | } else { |
8de8c873 | 511 | error = SCTP_ERROR_NO_RESOURCE; |
1da177e4 LT |
512 | } |
513 | } else { | |
8de8c873 SS |
514 | sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
515 | error = SCTP_ERROR_INV_PARAM; | |
1da177e4 | 516 | } |
8de8c873 SS |
517 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, |
518 | asoc, chunk->transport); | |
1da177e4 LT |
519 | } |
520 | ||
521 | /* Tag the variable length parameters. Note that we never | |
522 | * convert the parameters in an INIT chunk. | |
523 | */ | |
524 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
525 | ||
526 | initchunk = (sctp_init_chunk_t *) chunk->chunk_hdr; | |
527 | ||
528 | sctp_add_cmd_sf(commands, SCTP_CMD_PEER_INIT, | |
529 | SCTP_PEER_INIT(initchunk)); | |
530 | ||
3f7a87d2 FF |
531 | /* Reset init error count upon receipt of INIT-ACK. */ |
532 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); | |
533 | ||
1da177e4 LT |
534 | /* 5.1 C) "A" shall stop the T1-init timer and leave |
535 | * COOKIE-WAIT state. "A" shall then ... start the T1-cookie | |
536 | * timer, and enter the COOKIE-ECHOED state. | |
537 | */ | |
538 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
539 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
540 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
541 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
542 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
543 | SCTP_STATE(SCTP_STATE_COOKIE_ECHOED)); | |
544 | ||
545 | /* 5.1 C) "A" shall then send the State Cookie received in the | |
546 | * INIT ACK chunk in a COOKIE ECHO chunk, ... | |
547 | */ | |
548 | /* If there is any errors to report, send the ERROR chunk generated | |
549 | * for unknown parameters as well. | |
550 | */ | |
551 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_COOKIE_ECHO, | |
552 | SCTP_CHUNK(err_chunk)); | |
553 | ||
554 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
555 | } |
556 | ||
557 | /* | |
558 | * Respond to a normal COOKIE ECHO chunk. | |
559 | * We are the side that is being asked for an association. | |
560 | * | |
561 | * Section: 5.1 Normal Establishment of an Association, D | |
562 | * D) Upon reception of the COOKIE ECHO chunk, Endpoint "Z" will reply | |
563 | * with a COOKIE ACK chunk after building a TCB and moving to | |
564 | * the ESTABLISHED state. A COOKIE ACK chunk may be bundled with | |
565 | * any pending DATA chunks (and/or SACK chunks), but the COOKIE ACK | |
566 | * chunk MUST be the first chunk in the packet. | |
567 | * | |
568 | * IMPLEMENTATION NOTE: An implementation may choose to send the | |
569 | * Communication Up notification to the SCTP user upon reception | |
570 | * of a valid COOKIE ECHO chunk. | |
571 | * | |
572 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
573 | * D) Rules for packet carrying a COOKIE ECHO | |
574 | * | |
575 | * - When sending a COOKIE ECHO, the endpoint MUST use the value of the | |
576 | * Initial Tag received in the INIT ACK. | |
577 | * | |
578 | * - The receiver of a COOKIE ECHO follows the procedures in Section 5. | |
579 | * | |
580 | * Inputs | |
581 | * (endpoint, asoc, chunk) | |
582 | * | |
583 | * Outputs | |
584 | * (asoc, reply_msg, msg_up, timers, counters) | |
585 | * | |
586 | * The return value is the disposition of the chunk. | |
587 | */ | |
588 | sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep, | |
589 | const struct sctp_association *asoc, | |
590 | const sctp_subtype_t type, void *arg, | |
591 | sctp_cmd_seq_t *commands) | |
592 | { | |
593 | struct sctp_chunk *chunk = arg; | |
594 | struct sctp_association *new_asoc; | |
595 | sctp_init_chunk_t *peer_init; | |
596 | struct sctp_chunk *repl; | |
df7deeb5 | 597 | struct sctp_ulpevent *ev, *ai_ev = NULL; |
1da177e4 LT |
598 | int error = 0; |
599 | struct sctp_chunk *err_chk_p; | |
609ee467 | 600 | struct sock *sk; |
1da177e4 LT |
601 | |
602 | /* If the packet is an OOTB packet which is temporarily on the | |
603 | * control endpoint, respond with an ABORT. | |
604 | */ | |
605 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) | |
ece25dfa | 606 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
1da177e4 LT |
607 | |
608 | /* Make sure that the COOKIE_ECHO chunk has a valid length. | |
609 | * In this case, we check that we have enough for at least a | |
610 | * chunk header. More detailed verification is done | |
611 | * in sctp_unpack_cookie(). | |
612 | */ | |
613 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
614 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
615 | ||
609ee467 VY |
616 | /* If the endpoint is not listening or if the number of associations |
617 | * on the TCP-style socket exceed the max backlog, respond with an | |
618 | * ABORT. | |
619 | */ | |
620 | sk = ep->base.sk; | |
621 | if (!sctp_sstate(sk, LISTENING) || | |
622 | (sctp_style(sk, TCP) && sk_acceptq_is_full(sk))) | |
623 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
624 | ||
1da177e4 LT |
625 | /* "Decode" the chunk. We have no optional parameters so we |
626 | * are in good shape. | |
627 | */ | |
d808ad9a | 628 | chunk->subh.cookie_hdr = |
1da177e4 | 629 | (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
630 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
631 | sizeof(sctp_chunkhdr_t))) | |
632 | goto nomem; | |
1da177e4 LT |
633 | |
634 | /* 5.1 D) Upon reception of the COOKIE ECHO chunk, Endpoint | |
635 | * "Z" will reply with a COOKIE ACK chunk after building a TCB | |
636 | * and moving to the ESTABLISHED state. | |
637 | */ | |
638 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
639 | &err_chk_p); | |
640 | ||
641 | /* FIXME: | |
642 | * If the re-build failed, what is the proper error path | |
643 | * from here? | |
644 | * | |
645 | * [We should abort the association. --piggy] | |
646 | */ | |
647 | if (!new_asoc) { | |
648 | /* FIXME: Several errors are possible. A bad cookie should | |
649 | * be silently discarded, but think about logging it too. | |
650 | */ | |
651 | switch (error) { | |
652 | case -SCTP_IERROR_NOMEM: | |
653 | goto nomem; | |
654 | ||
655 | case -SCTP_IERROR_STALE_COOKIE: | |
656 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
657 | err_chk_p); | |
658 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
659 | ||
660 | case -SCTP_IERROR_BAD_SIG: | |
661 | default: | |
662 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 663 | } |
1da177e4 LT |
664 | } |
665 | ||
1da177e4 | 666 | |
df7deeb5 VY |
667 | /* Delay state machine commands until later. |
668 | * | |
669 | * Re-build the bind address for the association is done in | |
1da177e4 LT |
670 | * the sctp_unpack_cookie() already. |
671 | */ | |
672 | /* This is a brand-new association, so these are not yet side | |
673 | * effects--it is safe to run them here. | |
674 | */ | |
675 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
676 | ||
677 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
6a1e5f33 | 678 | &chunk->subh.cookie_hdr->c.peer_addr, |
1da177e4 LT |
679 | peer_init, GFP_ATOMIC)) |
680 | goto nomem_init; | |
681 | ||
682 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
683 | if (!repl) | |
df7deeb5 | 684 | goto nomem_init; |
1da177e4 LT |
685 | |
686 | /* RFC 2960 5.1 Normal Establishment of an Association | |
687 | * | |
688 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
689 | * send the Communication Up notification to the SCTP user | |
690 | * upon reception of a valid COOKIE ECHO chunk. | |
691 | */ | |
692 | ev = sctp_ulpevent_make_assoc_change(new_asoc, 0, SCTP_COMM_UP, 0, | |
693 | new_asoc->c.sinit_num_ostreams, | |
694 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 695 | NULL, GFP_ATOMIC); |
1da177e4 LT |
696 | if (!ev) |
697 | goto nomem_ev; | |
698 | ||
d808ad9a | 699 | /* Sockets API Draft Section 5.3.1.6 |
0f3fffd8 | 700 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 701 | * delivers this notification to inform the application that of the |
0f3fffd8 | 702 | * peers requested adaptation layer. |
1da177e4 | 703 | */ |
0f3fffd8 ISJ |
704 | if (new_asoc->peer.adaptation_ind) { |
705 | ai_ev = sctp_ulpevent_make_adaptation_indication(new_asoc, | |
1da177e4 | 706 | GFP_ATOMIC); |
df7deeb5 VY |
707 | if (!ai_ev) |
708 | goto nomem_aiev; | |
709 | } | |
710 | ||
711 | /* Add all the state machine commands now since we've created | |
712 | * everything. This way we don't introduce memory corruptions | |
713 | * during side-effect processing and correclty count established | |
714 | * associations. | |
715 | */ | |
716 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
717 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
718 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
719 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
720 | SCTP_INC_STATS(SCTP_MIB_PASSIVEESTABS); | |
721 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
722 | ||
723 | if (new_asoc->autoclose) | |
724 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
725 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
726 | ||
727 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL()); | |
1da177e4 | 728 | |
df7deeb5 VY |
729 | /* This will send the COOKIE ACK */ |
730 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
731 | ||
732 | /* Queue the ASSOC_CHANGE event */ | |
733 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
734 | ||
735 | /* Send up the Adaptation Layer Indication event */ | |
736 | if (ai_ev) | |
1da177e4 | 737 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, |
df7deeb5 | 738 | SCTP_ULPEVENT(ai_ev)); |
1da177e4 LT |
739 | |
740 | return SCTP_DISPOSITION_CONSUME; | |
741 | ||
df7deeb5 VY |
742 | nomem_aiev: |
743 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
744 | nomem_ev: |
745 | sctp_chunk_free(repl); | |
1da177e4 LT |
746 | nomem_init: |
747 | sctp_association_free(new_asoc); | |
748 | nomem: | |
749 | return SCTP_DISPOSITION_NOMEM; | |
750 | } | |
751 | ||
752 | /* | |
753 | * Respond to a normal COOKIE ACK chunk. | |
754 | * We are the side that is being asked for an association. | |
755 | * | |
756 | * RFC 2960 5.1 Normal Establishment of an Association | |
757 | * | |
758 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move from the | |
759 | * COOKIE-ECHOED state to the ESTABLISHED state, stopping the T1-cookie | |
760 | * timer. It may also notify its ULP about the successful | |
761 | * establishment of the association with a Communication Up | |
762 | * notification (see Section 10). | |
763 | * | |
764 | * Verification Tag: | |
765 | * Inputs | |
766 | * (endpoint, asoc, chunk) | |
767 | * | |
768 | * Outputs | |
769 | * (asoc, reply_msg, msg_up, timers, counters) | |
770 | * | |
771 | * The return value is the disposition of the chunk. | |
772 | */ | |
773 | sctp_disposition_t sctp_sf_do_5_1E_ca(const struct sctp_endpoint *ep, | |
774 | const struct sctp_association *asoc, | |
775 | const sctp_subtype_t type, void *arg, | |
776 | sctp_cmd_seq_t *commands) | |
777 | { | |
778 | struct sctp_chunk *chunk = arg; | |
779 | struct sctp_ulpevent *ev; | |
780 | ||
781 | if (!sctp_vtag_verify(chunk, asoc)) | |
782 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
783 | ||
784 | /* Verify that the chunk length for the COOKIE-ACK is OK. | |
785 | * If we don't do this, any bundled chunks may be junked. | |
786 | */ | |
787 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
788 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
789 | commands); | |
790 | ||
791 | /* Reset init error count upon receipt of COOKIE-ACK, | |
792 | * to avoid problems with the managemement of this | |
793 | * counter in stale cookie situations when a transition back | |
794 | * from the COOKIE-ECHOED state to the COOKIE-WAIT | |
795 | * state is performed. | |
796 | */ | |
3f7a87d2 | 797 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); |
1da177e4 LT |
798 | |
799 | /* RFC 2960 5.1 Normal Establishment of an Association | |
800 | * | |
801 | * E) Upon reception of the COOKIE ACK, endpoint "A" will move | |
802 | * from the COOKIE-ECHOED state to the ESTABLISHED state, | |
803 | * stopping the T1-cookie timer. | |
804 | */ | |
805 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
806 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
807 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
808 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
809 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
810 | SCTP_INC_STATS(SCTP_MIB_ACTIVEESTABS); | |
811 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
812 | if (asoc->autoclose) | |
813 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
814 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
815 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL()); | |
816 | ||
817 | /* It may also notify its ULP about the successful | |
818 | * establishment of the association with a Communication Up | |
819 | * notification (see Section 10). | |
820 | */ | |
821 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_UP, | |
822 | 0, asoc->c.sinit_num_ostreams, | |
823 | asoc->c.sinit_max_instreams, | |
a5a35e76 | 824 | NULL, GFP_ATOMIC); |
1da177e4 LT |
825 | |
826 | if (!ev) | |
827 | goto nomem; | |
828 | ||
829 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
830 | ||
831 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 832 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 833 | * delivers this notification to inform the application that of the |
0f3fffd8 | 834 | * peers requested adaptation layer. |
1da177e4 | 835 | */ |
0f3fffd8 ISJ |
836 | if (asoc->peer.adaptation_ind) { |
837 | ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); | |
1da177e4 LT |
838 | if (!ev) |
839 | goto nomem; | |
840 | ||
841 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
842 | SCTP_ULPEVENT(ev)); | |
843 | } | |
844 | ||
845 | return SCTP_DISPOSITION_CONSUME; | |
846 | nomem: | |
847 | return SCTP_DISPOSITION_NOMEM; | |
848 | } | |
849 | ||
850 | /* Generate and sendout a heartbeat packet. */ | |
851 | static sctp_disposition_t sctp_sf_heartbeat(const struct sctp_endpoint *ep, | |
852 | const struct sctp_association *asoc, | |
853 | const sctp_subtype_t type, | |
854 | void *arg, | |
855 | sctp_cmd_seq_t *commands) | |
856 | { | |
857 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
858 | struct sctp_chunk *reply; | |
859 | sctp_sender_hb_info_t hbinfo; | |
860 | size_t paylen = 0; | |
861 | ||
862 | hbinfo.param_hdr.type = SCTP_PARAM_HEARTBEAT_INFO; | |
863 | hbinfo.param_hdr.length = htons(sizeof(sctp_sender_hb_info_t)); | |
63de08f4 | 864 | hbinfo.daddr = transport->ipaddr; |
1da177e4 | 865 | hbinfo.sent_at = jiffies; |
ad8fec17 | 866 | hbinfo.hb_nonce = transport->hb_nonce; |
1da177e4 LT |
867 | |
868 | /* Send a heartbeat to our peer. */ | |
869 | paylen = sizeof(sctp_sender_hb_info_t); | |
870 | reply = sctp_make_heartbeat(asoc, transport, &hbinfo, paylen); | |
871 | if (!reply) | |
872 | return SCTP_DISPOSITION_NOMEM; | |
873 | ||
874 | /* Set rto_pending indicating that an RTT measurement | |
875 | * is started with this heartbeat chunk. | |
876 | */ | |
877 | sctp_add_cmd_sf(commands, SCTP_CMD_RTO_PENDING, | |
878 | SCTP_TRANSPORT(transport)); | |
879 | ||
880 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
881 | return SCTP_DISPOSITION_CONSUME; | |
882 | } | |
883 | ||
884 | /* Generate a HEARTBEAT packet on the given transport. */ | |
885 | sctp_disposition_t sctp_sf_sendbeat_8_3(const struct sctp_endpoint *ep, | |
886 | const struct sctp_association *asoc, | |
887 | const sctp_subtype_t type, | |
888 | void *arg, | |
889 | sctp_cmd_seq_t *commands) | |
890 | { | |
891 | struct sctp_transport *transport = (struct sctp_transport *) arg; | |
892 | ||
e2c2fc2c | 893 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
894 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
895 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
896 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
897 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 898 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
899 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
900 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
901 | return SCTP_DISPOSITION_DELETE_TCB; | |
902 | } | |
903 | ||
904 | /* Section 3.3.5. | |
905 | * The Sender-specific Heartbeat Info field should normally include | |
906 | * information about the sender's current time when this HEARTBEAT | |
907 | * chunk is sent and the destination transport address to which this | |
908 | * HEARTBEAT is sent (see Section 8.3). | |
909 | */ | |
910 | ||
52ccb8e9 | 911 | if (transport->param_flags & SPP_HB_ENABLE) { |
1da177e4 LT |
912 | if (SCTP_DISPOSITION_NOMEM == |
913 | sctp_sf_heartbeat(ep, asoc, type, arg, | |
914 | commands)) | |
915 | return SCTP_DISPOSITION_NOMEM; | |
916 | /* Set transport error counter and association error counter | |
917 | * when sending heartbeat. | |
918 | */ | |
919 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_RESET, | |
920 | SCTP_TRANSPORT(transport)); | |
921 | } | |
922 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMER_UPDATE, | |
923 | SCTP_TRANSPORT(transport)); | |
924 | ||
d808ad9a | 925 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
926 | } |
927 | ||
928 | /* | |
929 | * Process an heartbeat request. | |
930 | * | |
931 | * Section: 8.3 Path Heartbeat | |
932 | * The receiver of the HEARTBEAT should immediately respond with a | |
933 | * HEARTBEAT ACK that contains the Heartbeat Information field copied | |
934 | * from the received HEARTBEAT chunk. | |
935 | * | |
936 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
937 | * When receiving an SCTP packet, the endpoint MUST ensure that the | |
938 | * value in the Verification Tag field of the received SCTP packet | |
939 | * matches its own Tag. If the received Verification Tag value does not | |
940 | * match the receiver's own tag value, the receiver shall silently | |
941 | * discard the packet and shall not process it any further except for | |
942 | * those cases listed in Section 8.5.1 below. | |
943 | * | |
944 | * Inputs | |
945 | * (endpoint, asoc, chunk) | |
946 | * | |
947 | * Outputs | |
948 | * (asoc, reply_msg, msg_up, timers, counters) | |
949 | * | |
950 | * The return value is the disposition of the chunk. | |
951 | */ | |
952 | sctp_disposition_t sctp_sf_beat_8_3(const struct sctp_endpoint *ep, | |
953 | const struct sctp_association *asoc, | |
954 | const sctp_subtype_t type, | |
955 | void *arg, | |
956 | sctp_cmd_seq_t *commands) | |
957 | { | |
958 | struct sctp_chunk *chunk = arg; | |
959 | struct sctp_chunk *reply; | |
960 | size_t paylen = 0; | |
961 | ||
962 | if (!sctp_vtag_verify(chunk, asoc)) | |
963 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
964 | ||
965 | /* Make sure that the HEARTBEAT chunk has a valid length. */ | |
966 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
967 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
968 | commands); | |
969 | ||
970 | /* 8.3 The receiver of the HEARTBEAT should immediately | |
971 | * respond with a HEARTBEAT ACK that contains the Heartbeat | |
972 | * Information field copied from the received HEARTBEAT chunk. | |
973 | */ | |
974 | chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data; | |
975 | paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t); | |
62b08083 SS |
976 | if (!pskb_pull(chunk->skb, paylen)) |
977 | goto nomem; | |
1da177e4 LT |
978 | |
979 | reply = sctp_make_heartbeat_ack(asoc, chunk, | |
980 | chunk->subh.hb_hdr, paylen); | |
981 | if (!reply) | |
982 | goto nomem; | |
983 | ||
984 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
985 | return SCTP_DISPOSITION_CONSUME; | |
986 | ||
987 | nomem: | |
988 | return SCTP_DISPOSITION_NOMEM; | |
989 | } | |
990 | ||
991 | /* | |
992 | * Process the returning HEARTBEAT ACK. | |
993 | * | |
994 | * Section: 8.3 Path Heartbeat | |
995 | * Upon the receipt of the HEARTBEAT ACK, the sender of the HEARTBEAT | |
996 | * should clear the error counter of the destination transport | |
997 | * address to which the HEARTBEAT was sent, and mark the destination | |
998 | * transport address as active if it is not so marked. The endpoint may | |
999 | * optionally report to the upper layer when an inactive destination | |
1000 | * address is marked as active due to the reception of the latest | |
1001 | * HEARTBEAT ACK. The receiver of the HEARTBEAT ACK must also | |
1002 | * clear the association overall error count as well (as defined | |
1003 | * in section 8.1). | |
1004 | * | |
1005 | * The receiver of the HEARTBEAT ACK should also perform an RTT | |
1006 | * measurement for that destination transport address using the time | |
1007 | * value carried in the HEARTBEAT ACK chunk. | |
1008 | * | |
1009 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
1010 | * | |
1011 | * Inputs | |
1012 | * (endpoint, asoc, chunk) | |
1013 | * | |
1014 | * Outputs | |
1015 | * (asoc, reply_msg, msg_up, timers, counters) | |
1016 | * | |
1017 | * The return value is the disposition of the chunk. | |
1018 | */ | |
1019 | sctp_disposition_t sctp_sf_backbeat_8_3(const struct sctp_endpoint *ep, | |
1020 | const struct sctp_association *asoc, | |
1021 | const sctp_subtype_t type, | |
1022 | void *arg, | |
1023 | sctp_cmd_seq_t *commands) | |
1024 | { | |
1025 | struct sctp_chunk *chunk = arg; | |
1026 | union sctp_addr from_addr; | |
1027 | struct sctp_transport *link; | |
1028 | sctp_sender_hb_info_t *hbinfo; | |
1029 | unsigned long max_interval; | |
1030 | ||
1031 | if (!sctp_vtag_verify(chunk, asoc)) | |
1032 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1033 | ||
1034 | /* Make sure that the HEARTBEAT-ACK chunk has a valid length. */ | |
1035 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_heartbeat_chunk_t))) | |
1036 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1037 | commands); | |
1038 | ||
1039 | hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; | |
a601266e VY |
1040 | /* Make sure that the length of the parameter is what we expect */ |
1041 | if (ntohs(hbinfo->param_hdr.length) != | |
1042 | sizeof(sctp_sender_hb_info_t)) { | |
1043 | return SCTP_DISPOSITION_DISCARD; | |
1044 | } | |
1045 | ||
1da177e4 | 1046 | from_addr = hbinfo->daddr; |
63de08f4 | 1047 | link = sctp_assoc_lookup_paddr(asoc, &from_addr); |
1da177e4 LT |
1048 | |
1049 | /* This should never happen, but lets log it if so. */ | |
3f7a87d2 FF |
1050 | if (unlikely(!link)) { |
1051 | if (from_addr.sa.sa_family == AF_INET6) { | |
d99fa429 WY |
1052 | if (net_ratelimit()) |
1053 | printk(KERN_WARNING | |
1054 | "%s association %p could not find address " | |
1055 | NIP6_FMT "\n", | |
1056 | __FUNCTION__, | |
1057 | asoc, | |
1058 | NIP6(from_addr.v6.sin6_addr)); | |
3f7a87d2 | 1059 | } else { |
d99fa429 WY |
1060 | if (net_ratelimit()) |
1061 | printk(KERN_WARNING | |
1062 | "%s association %p could not find address " | |
1063 | NIPQUAD_FMT "\n", | |
1064 | __FUNCTION__, | |
1065 | asoc, | |
1066 | NIPQUAD(from_addr.v4.sin_addr.s_addr)); | |
3f7a87d2 | 1067 | } |
1da177e4 LT |
1068 | return SCTP_DISPOSITION_DISCARD; |
1069 | } | |
1070 | ||
ad8fec17 SS |
1071 | /* Validate the 64-bit random nonce. */ |
1072 | if (hbinfo->hb_nonce != link->hb_nonce) | |
1073 | return SCTP_DISPOSITION_DISCARD; | |
1074 | ||
52ccb8e9 | 1075 | max_interval = link->hbinterval + link->rto; |
1da177e4 LT |
1076 | |
1077 | /* Check if the timestamp looks valid. */ | |
1078 | if (time_after(hbinfo->sent_at, jiffies) || | |
1079 | time_after(jiffies, hbinfo->sent_at + max_interval)) { | |
1080 | SCTP_DEBUG_PRINTK("%s: HEARTBEAT ACK with invalid timestamp" | |
1081 | "received for transport: %p\n", | |
1082 | __FUNCTION__, link); | |
1083 | return SCTP_DISPOSITION_DISCARD; | |
1084 | } | |
1085 | ||
1086 | /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of | |
1087 | * the HEARTBEAT should clear the error counter of the | |
1088 | * destination transport address to which the HEARTBEAT was | |
1089 | * sent and mark the destination transport address as active if | |
1090 | * it is not so marked. | |
1091 | */ | |
1092 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_ON, SCTP_TRANSPORT(link)); | |
1093 | ||
1094 | return SCTP_DISPOSITION_CONSUME; | |
1095 | } | |
1096 | ||
1097 | /* Helper function to send out an abort for the restart | |
1098 | * condition. | |
1099 | */ | |
1100 | static int sctp_sf_send_restart_abort(union sctp_addr *ssa, | |
1101 | struct sctp_chunk *init, | |
1102 | sctp_cmd_seq_t *commands) | |
1103 | { | |
1104 | int len; | |
1105 | struct sctp_packet *pkt; | |
1106 | union sctp_addr_param *addrparm; | |
1107 | struct sctp_errhdr *errhdr; | |
1108 | struct sctp_endpoint *ep; | |
1109 | char buffer[sizeof(struct sctp_errhdr)+sizeof(union sctp_addr_param)]; | |
1110 | struct sctp_af *af = sctp_get_af_specific(ssa->v4.sin_family); | |
1111 | ||
1112 | /* Build the error on the stack. We are way to malloc crazy | |
1113 | * throughout the code today. | |
1114 | */ | |
1115 | errhdr = (struct sctp_errhdr *)buffer; | |
1116 | addrparm = (union sctp_addr_param *)errhdr->variable; | |
1117 | ||
1118 | /* Copy into a parm format. */ | |
1119 | len = af->to_addr_param(ssa, addrparm); | |
1120 | len += sizeof(sctp_errhdr_t); | |
1121 | ||
1122 | errhdr->cause = SCTP_ERROR_RESTART; | |
1123 | errhdr->length = htons(len); | |
1124 | ||
1125 | /* Assign to the control socket. */ | |
1126 | ep = sctp_sk((sctp_get_ctl_sock()))->ep; | |
1127 | ||
1128 | /* Association is NULL since this may be a restart attack and we | |
1129 | * want to send back the attacker's vtag. | |
1130 | */ | |
1131 | pkt = sctp_abort_pkt_new(ep, NULL, init, errhdr, len); | |
1132 | ||
1133 | if (!pkt) | |
1134 | goto out; | |
1135 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, SCTP_PACKET(pkt)); | |
1136 | ||
1137 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1138 | ||
1139 | /* Discard the rest of the inbound packet. */ | |
1140 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); | |
1141 | ||
1142 | out: | |
1143 | /* Even if there is no memory, treat as a failure so | |
1144 | * the packet will get dropped. | |
1145 | */ | |
1146 | return 0; | |
1147 | } | |
1148 | ||
1149 | /* A restart is occurring, check to make sure no new addresses | |
1150 | * are being added as we may be under a takeover attack. | |
1151 | */ | |
1152 | static int sctp_sf_check_restart_addrs(const struct sctp_association *new_asoc, | |
1153 | const struct sctp_association *asoc, | |
1154 | struct sctp_chunk *init, | |
1155 | sctp_cmd_seq_t *commands) | |
1156 | { | |
1157 | struct sctp_transport *new_addr, *addr; | |
1158 | struct list_head *pos, *pos2; | |
1159 | int found; | |
1160 | ||
1161 | /* Implementor's Guide - Sectin 5.2.2 | |
1162 | * ... | |
1163 | * Before responding the endpoint MUST check to see if the | |
1164 | * unexpected INIT adds new addresses to the association. If new | |
1165 | * addresses are added to the association, the endpoint MUST respond | |
1166 | * with an ABORT.. | |
1167 | */ | |
1168 | ||
1169 | /* Search through all current addresses and make sure | |
1170 | * we aren't adding any new ones. | |
1171 | */ | |
1172 | new_addr = NULL; | |
1173 | found = 0; | |
1174 | ||
1175 | list_for_each(pos, &new_asoc->peer.transport_addr_list) { | |
1176 | new_addr = list_entry(pos, struct sctp_transport, transports); | |
1177 | found = 0; | |
1178 | list_for_each(pos2, &asoc->peer.transport_addr_list) { | |
1179 | addr = list_entry(pos2, struct sctp_transport, | |
1180 | transports); | |
5f242a13 AV |
1181 | if (sctp_cmp_addr_exact(&new_addr->ipaddr, |
1182 | &addr->ipaddr)) { | |
1da177e4 LT |
1183 | found = 1; |
1184 | break; | |
1185 | } | |
1186 | } | |
1187 | if (!found) | |
1188 | break; | |
1189 | } | |
1190 | ||
1191 | /* If a new address was added, ABORT the sender. */ | |
1192 | if (!found && new_addr) { | |
7dd8a582 | 1193 | sctp_sf_send_restart_abort(&new_addr->ipaddr, init, commands); |
1da177e4 LT |
1194 | } |
1195 | ||
1196 | /* Return success if all addresses were found. */ | |
1197 | return found; | |
1198 | } | |
1199 | ||
1200 | /* Populate the verification/tie tags based on overlapping INIT | |
1201 | * scenario. | |
1202 | * | |
1203 | * Note: Do not use in CLOSED or SHUTDOWN-ACK-SENT state. | |
1204 | */ | |
1205 | static void sctp_tietags_populate(struct sctp_association *new_asoc, | |
1206 | const struct sctp_association *asoc) | |
1207 | { | |
1208 | switch (asoc->state) { | |
1209 | ||
1210 | /* 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State */ | |
1211 | ||
1212 | case SCTP_STATE_COOKIE_WAIT: | |
1213 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1214 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1215 | new_asoc->c.peer_ttag = 0; | |
1216 | break; | |
1217 | ||
1218 | case SCTP_STATE_COOKIE_ECHOED: | |
1219 | new_asoc->c.my_vtag = asoc->c.my_vtag; | |
1220 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1221 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1222 | break; | |
1223 | ||
1224 | /* 5.2.2 Unexpected INIT in States Other than CLOSED, COOKIE-ECHOED, | |
1225 | * COOKIE-WAIT and SHUTDOWN-ACK-SENT | |
1226 | */ | |
1227 | default: | |
1228 | new_asoc->c.my_ttag = asoc->c.my_vtag; | |
1229 | new_asoc->c.peer_ttag = asoc->c.peer_vtag; | |
1230 | break; | |
3ff50b79 | 1231 | } |
1da177e4 LT |
1232 | |
1233 | /* Other parameters for the endpoint SHOULD be copied from the | |
1234 | * existing parameters of the association (e.g. number of | |
1235 | * outbound streams) into the INIT ACK and cookie. | |
1236 | */ | |
1237 | new_asoc->rwnd = asoc->rwnd; | |
1238 | new_asoc->c.sinit_num_ostreams = asoc->c.sinit_num_ostreams; | |
1239 | new_asoc->c.sinit_max_instreams = asoc->c.sinit_max_instreams; | |
1240 | new_asoc->c.initial_tsn = asoc->c.initial_tsn; | |
1241 | } | |
1242 | ||
1243 | /* | |
1244 | * Compare vtag/tietag values to determine unexpected COOKIE-ECHO | |
1245 | * handling action. | |
1246 | * | |
1247 | * RFC 2960 5.2.4 Handle a COOKIE ECHO when a TCB exists. | |
1248 | * | |
1249 | * Returns value representing action to be taken. These action values | |
1250 | * correspond to Action/Description values in RFC 2960, Table 2. | |
1251 | */ | |
1252 | static char sctp_tietags_compare(struct sctp_association *new_asoc, | |
1253 | const struct sctp_association *asoc) | |
1254 | { | |
1255 | /* In this case, the peer may have restarted. */ | |
1256 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1257 | (asoc->c.peer_vtag != new_asoc->c.peer_vtag) && | |
1258 | (asoc->c.my_vtag == new_asoc->c.my_ttag) && | |
1259 | (asoc->c.peer_vtag == new_asoc->c.peer_ttag)) | |
1260 | return 'A'; | |
1261 | ||
1262 | /* Collision case B. */ | |
1263 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1264 | ((asoc->c.peer_vtag != new_asoc->c.peer_vtag) || | |
1265 | (0 == asoc->c.peer_vtag))) { | |
1266 | return 'B'; | |
1267 | } | |
1268 | ||
1269 | /* Collision case D. */ | |
1270 | if ((asoc->c.my_vtag == new_asoc->c.my_vtag) && | |
1271 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag)) | |
1272 | return 'D'; | |
1273 | ||
1274 | /* Collision case C. */ | |
1275 | if ((asoc->c.my_vtag != new_asoc->c.my_vtag) && | |
1276 | (asoc->c.peer_vtag == new_asoc->c.peer_vtag) && | |
1277 | (0 == new_asoc->c.my_ttag) && | |
1278 | (0 == new_asoc->c.peer_ttag)) | |
1279 | return 'C'; | |
1280 | ||
1281 | /* No match to any of the special cases; discard this packet. */ | |
1282 | return 'E'; | |
1283 | } | |
1284 | ||
1285 | /* Common helper routine for both duplicate and simulataneous INIT | |
1286 | * chunk handling. | |
1287 | */ | |
1288 | static sctp_disposition_t sctp_sf_do_unexpected_init( | |
1289 | const struct sctp_endpoint *ep, | |
1290 | const struct sctp_association *asoc, | |
1291 | const sctp_subtype_t type, | |
1292 | void *arg, sctp_cmd_seq_t *commands) | |
1293 | { | |
1294 | sctp_disposition_t retval; | |
1295 | struct sctp_chunk *chunk = arg; | |
1296 | struct sctp_chunk *repl; | |
1297 | struct sctp_association *new_asoc; | |
1298 | struct sctp_chunk *err_chunk; | |
1299 | struct sctp_packet *packet; | |
1300 | sctp_unrecognized_param_t *unk_param; | |
1301 | int len; | |
1302 | ||
1303 | /* 6.10 Bundling | |
1304 | * An endpoint MUST NOT bundle INIT, INIT ACK or | |
1305 | * SHUTDOWN COMPLETE with any other chunks. | |
1306 | * | |
1307 | * IG Section 2.11.2 | |
1308 | * Furthermore, we require that the receiver of an INIT chunk MUST | |
1309 | * enforce these rules by silently discarding an arriving packet | |
1310 | * with an INIT chunk that is bundled with other chunks. | |
1311 | */ | |
1312 | if (!chunk->singleton) | |
1313 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1314 | ||
1315 | /* 3.1 A packet containing an INIT chunk MUST have a zero Verification | |
d808ad9a | 1316 | * Tag. |
1da177e4 LT |
1317 | */ |
1318 | if (chunk->sctp_hdr->vtag != 0) | |
1319 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); | |
1320 | ||
1321 | /* Make sure that the INIT chunk has a valid length. | |
1322 | * In this case, we generate a protocol violation since we have | |
1323 | * an association established. | |
1324 | */ | |
1325 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_init_chunk_t))) | |
1326 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1327 | commands); | |
1328 | /* Grab the INIT header. */ | |
1329 | chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data; | |
1330 | ||
1331 | /* Tag the variable length parameters. */ | |
1332 | chunk->param_hdr.v = skb_pull(chunk->skb, sizeof(sctp_inithdr_t)); | |
1333 | ||
1334 | /* Verify the INIT chunk before processing it. */ | |
1335 | err_chunk = NULL; | |
1336 | if (!sctp_verify_init(asoc, chunk->chunk_hdr->type, | |
1337 | (sctp_init_chunk_t *)chunk->chunk_hdr, chunk, | |
1338 | &err_chunk)) { | |
1339 | /* This chunk contains fatal error. It is to be discarded. | |
1340 | * Send an ABORT, with causes if there is any. | |
1341 | */ | |
1342 | if (err_chunk) { | |
1343 | packet = sctp_abort_pkt_new(ep, asoc, arg, | |
1344 | (__u8 *)(err_chunk->chunk_hdr) + | |
1345 | sizeof(sctp_chunkhdr_t), | |
1346 | ntohs(err_chunk->chunk_hdr->length) - | |
1347 | sizeof(sctp_chunkhdr_t)); | |
1348 | ||
1349 | if (packet) { | |
1350 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
1351 | SCTP_PACKET(packet)); | |
1352 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1353 | retval = SCTP_DISPOSITION_CONSUME; | |
1354 | } else { | |
1355 | retval = SCTP_DISPOSITION_NOMEM; | |
1356 | } | |
1357 | goto cleanup; | |
1358 | } else { | |
1359 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, | |
1360 | commands); | |
1361 | } | |
1362 | } | |
1363 | ||
1364 | /* | |
1365 | * Other parameters for the endpoint SHOULD be copied from the | |
1366 | * existing parameters of the association (e.g. number of | |
1367 | * outbound streams) into the INIT ACK and cookie. | |
1368 | * FIXME: We are copying parameters from the endpoint not the | |
1369 | * association. | |
1370 | */ | |
1371 | new_asoc = sctp_make_temp_asoc(ep, chunk, GFP_ATOMIC); | |
1372 | if (!new_asoc) | |
1373 | goto nomem; | |
1374 | ||
1375 | /* In the outbound INIT ACK the endpoint MUST copy its current | |
1376 | * Verification Tag and Peers Verification tag into a reserved | |
1377 | * place (local tie-tag and per tie-tag) within the state cookie. | |
1378 | */ | |
1379 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1380 | sctp_source(chunk), | |
1381 | (sctp_init_chunk_t *)chunk->chunk_hdr, | |
df7deeb5 VY |
1382 | GFP_ATOMIC)) |
1383 | goto nomem; | |
1da177e4 LT |
1384 | |
1385 | /* Make sure no new addresses are being added during the | |
1386 | * restart. Do not do this check for COOKIE-WAIT state, | |
1387 | * since there are no peer addresses to check against. | |
1388 | * Upon return an ABORT will have been sent if needed. | |
1389 | */ | |
1390 | if (!sctp_state(asoc, COOKIE_WAIT)) { | |
1391 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, | |
1392 | commands)) { | |
1393 | retval = SCTP_DISPOSITION_CONSUME; | |
df7deeb5 | 1394 | goto nomem_retval; |
1da177e4 LT |
1395 | } |
1396 | } | |
1397 | ||
1398 | sctp_tietags_populate(new_asoc, asoc); | |
1399 | ||
1400 | /* B) "Z" shall respond immediately with an INIT ACK chunk. */ | |
1401 | ||
1402 | /* If there are errors need to be reported for unknown parameters, | |
1403 | * make sure to reserve enough room in the INIT ACK for them. | |
1404 | */ | |
1405 | len = 0; | |
1406 | if (err_chunk) { | |
1407 | len = ntohs(err_chunk->chunk_hdr->length) - | |
1408 | sizeof(sctp_chunkhdr_t); | |
1409 | } | |
1410 | ||
1411 | if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0) | |
1412 | goto nomem; | |
1413 | ||
1414 | repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len); | |
1415 | if (!repl) | |
1416 | goto nomem; | |
1417 | ||
1418 | /* If there are errors need to be reported for unknown parameters, | |
1419 | * include them in the outgoing INIT ACK as "Unrecognized parameter" | |
1420 | * parameter. | |
1421 | */ | |
1422 | if (err_chunk) { | |
1423 | /* Get the "Unrecognized parameter" parameter(s) out of the | |
1424 | * ERROR chunk generated by sctp_verify_init(). Since the | |
1425 | * error cause code for "unknown parameter" and the | |
1426 | * "Unrecognized parameter" type is the same, we can | |
1427 | * construct the parameters in INIT ACK by copying the | |
1428 | * ERROR causes over. | |
1429 | */ | |
1430 | unk_param = (sctp_unrecognized_param_t *) | |
1431 | ((__u8 *)(err_chunk->chunk_hdr) + | |
1432 | sizeof(sctp_chunkhdr_t)); | |
1433 | /* Replace the cause code with the "Unrecognized parameter" | |
1434 | * parameter type. | |
1435 | */ | |
1436 | sctp_addto_chunk(repl, len, unk_param); | |
1437 | } | |
1438 | ||
1439 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1440 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1441 | ||
1442 | /* | |
1443 | * Note: After sending out INIT ACK with the State Cookie parameter, | |
1444 | * "Z" MUST NOT allocate any resources for this new association. | |
1445 | * Otherwise, "Z" will be vulnerable to resource attacks. | |
1446 | */ | |
1447 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1448 | retval = SCTP_DISPOSITION_CONSUME; | |
1449 | ||
df7deeb5 VY |
1450 | return retval; |
1451 | ||
1452 | nomem: | |
1453 | retval = SCTP_DISPOSITION_NOMEM; | |
1454 | nomem_retval: | |
1455 | if (new_asoc) | |
1456 | sctp_association_free(new_asoc); | |
1da177e4 LT |
1457 | cleanup: |
1458 | if (err_chunk) | |
1459 | sctp_chunk_free(err_chunk); | |
1460 | return retval; | |
1da177e4 LT |
1461 | } |
1462 | ||
1463 | /* | |
1464 | * Handle simultanous INIT. | |
1465 | * This means we started an INIT and then we got an INIT request from | |
1466 | * our peer. | |
1467 | * | |
1468 | * Section: 5.2.1 INIT received in COOKIE-WAIT or COOKIE-ECHOED State (Item B) | |
1469 | * This usually indicates an initialization collision, i.e., each | |
1470 | * endpoint is attempting, at about the same time, to establish an | |
1471 | * association with the other endpoint. | |
1472 | * | |
1473 | * Upon receipt of an INIT in the COOKIE-WAIT or COOKIE-ECHOED state, an | |
1474 | * endpoint MUST respond with an INIT ACK using the same parameters it | |
1475 | * sent in its original INIT chunk (including its Verification Tag, | |
1476 | * unchanged). These original parameters are combined with those from the | |
1477 | * newly received INIT chunk. The endpoint shall also generate a State | |
1478 | * Cookie with the INIT ACK. The endpoint uses the parameters sent in its | |
1479 | * INIT to calculate the State Cookie. | |
1480 | * | |
1481 | * After that, the endpoint MUST NOT change its state, the T1-init | |
1482 | * timer shall be left running and the corresponding TCB MUST NOT be | |
1483 | * destroyed. The normal procedures for handling State Cookies when | |
1484 | * a TCB exists will resolve the duplicate INITs to a single association. | |
1485 | * | |
1486 | * For an endpoint that is in the COOKIE-ECHOED state it MUST populate | |
1487 | * its Tie-Tags with the Tag information of itself and its peer (see | |
1488 | * section 5.2.2 for a description of the Tie-Tags). | |
1489 | * | |
1490 | * Verification Tag: Not explicit, but an INIT can not have a valid | |
1491 | * verification tag, so we skip the check. | |
1492 | * | |
1493 | * Inputs | |
1494 | * (endpoint, asoc, chunk) | |
1495 | * | |
1496 | * Outputs | |
1497 | * (asoc, reply_msg, msg_up, timers, counters) | |
1498 | * | |
1499 | * The return value is the disposition of the chunk. | |
1500 | */ | |
1501 | sctp_disposition_t sctp_sf_do_5_2_1_siminit(const struct sctp_endpoint *ep, | |
1502 | const struct sctp_association *asoc, | |
1503 | const sctp_subtype_t type, | |
1504 | void *arg, | |
1505 | sctp_cmd_seq_t *commands) | |
1506 | { | |
1507 | /* Call helper to do the real work for both simulataneous and | |
1508 | * duplicate INIT chunk handling. | |
1509 | */ | |
1510 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1511 | } | |
1512 | ||
1513 | /* | |
1514 | * Handle duplicated INIT messages. These are usually delayed | |
1515 | * restransmissions. | |
1516 | * | |
1517 | * Section: 5.2.2 Unexpected INIT in States Other than CLOSED, | |
1518 | * COOKIE-ECHOED and COOKIE-WAIT | |
1519 | * | |
1520 | * Unless otherwise stated, upon reception of an unexpected INIT for | |
1521 | * this association, the endpoint shall generate an INIT ACK with a | |
1522 | * State Cookie. In the outbound INIT ACK the endpoint MUST copy its | |
1523 | * current Verification Tag and peer's Verification Tag into a reserved | |
1524 | * place within the state cookie. We shall refer to these locations as | |
1525 | * the Peer's-Tie-Tag and the Local-Tie-Tag. The outbound SCTP packet | |
1526 | * containing this INIT ACK MUST carry a Verification Tag value equal to | |
1527 | * the Initiation Tag found in the unexpected INIT. And the INIT ACK | |
1528 | * MUST contain a new Initiation Tag (randomly generated see Section | |
1529 | * 5.3.1). Other parameters for the endpoint SHOULD be copied from the | |
1530 | * existing parameters of the association (e.g. number of outbound | |
1531 | * streams) into the INIT ACK and cookie. | |
1532 | * | |
1533 | * After sending out the INIT ACK, the endpoint shall take no further | |
1534 | * actions, i.e., the existing association, including its current state, | |
1535 | * and the corresponding TCB MUST NOT be changed. | |
1536 | * | |
1537 | * Note: Only when a TCB exists and the association is not in a COOKIE- | |
1538 | * WAIT state are the Tie-Tags populated. For a normal association INIT | |
1539 | * (i.e. the endpoint is in a COOKIE-WAIT state), the Tie-Tags MUST be | |
1540 | * set to 0 (indicating that no previous TCB existed). The INIT ACK and | |
1541 | * State Cookie are populated as specified in section 5.2.1. | |
1542 | * | |
1543 | * Verification Tag: Not specified, but an INIT has no way of knowing | |
1544 | * what the verification tag could be, so we ignore it. | |
1545 | * | |
1546 | * Inputs | |
1547 | * (endpoint, asoc, chunk) | |
1548 | * | |
1549 | * Outputs | |
1550 | * (asoc, reply_msg, msg_up, timers, counters) | |
1551 | * | |
1552 | * The return value is the disposition of the chunk. | |
1553 | */ | |
1554 | sctp_disposition_t sctp_sf_do_5_2_2_dupinit(const struct sctp_endpoint *ep, | |
1555 | const struct sctp_association *asoc, | |
1556 | const sctp_subtype_t type, | |
1557 | void *arg, | |
1558 | sctp_cmd_seq_t *commands) | |
1559 | { | |
1560 | /* Call helper to do the real work for both simulataneous and | |
1561 | * duplicate INIT chunk handling. | |
1562 | */ | |
1563 | return sctp_sf_do_unexpected_init(ep, asoc, type, arg, commands); | |
1564 | } | |
1565 | ||
1566 | ||
610ab73a VY |
1567 | /* |
1568 | * Unexpected INIT-ACK handler. | |
1569 | * | |
1570 | * Section 5.2.3 | |
1571 | * If an INIT ACK received by an endpoint in any state other than the | |
1572 | * COOKIE-WAIT state, the endpoint should discard the INIT ACK chunk. | |
1573 | * An unexpected INIT ACK usually indicates the processing of an old or | |
1574 | * duplicated INIT chunk. | |
1575 | */ | |
1576 | sctp_disposition_t sctp_sf_do_5_2_3_initack(const struct sctp_endpoint *ep, | |
1577 | const struct sctp_association *asoc, | |
1578 | const sctp_subtype_t type, | |
1579 | void *arg, sctp_cmd_seq_t *commands) | |
1580 | { | |
1581 | /* Per the above section, we'll discard the chunk if we have an | |
1582 | * endpoint. If this is an OOTB INIT-ACK, treat it as such. | |
1583 | */ | |
d808ad9a | 1584 | if (ep == sctp_sk((sctp_get_ctl_sock()))->ep) |
610ab73a VY |
1585 | return sctp_sf_ootb(ep, asoc, type, arg, commands); |
1586 | else | |
1587 | return sctp_sf_discard_chunk(ep, asoc, type, arg, commands); | |
1588 | } | |
1da177e4 LT |
1589 | |
1590 | /* Unexpected COOKIE-ECHO handler for peer restart (Table 2, action 'A') | |
1591 | * | |
1592 | * Section 5.2.4 | |
1593 | * A) In this case, the peer may have restarted. | |
1594 | */ | |
1595 | static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep, | |
1596 | const struct sctp_association *asoc, | |
1597 | struct sctp_chunk *chunk, | |
1598 | sctp_cmd_seq_t *commands, | |
1599 | struct sctp_association *new_asoc) | |
1600 | { | |
1601 | sctp_init_chunk_t *peer_init; | |
1602 | struct sctp_ulpevent *ev; | |
1603 | struct sctp_chunk *repl; | |
1604 | struct sctp_chunk *err; | |
1605 | sctp_disposition_t disposition; | |
1606 | ||
1607 | /* new_asoc is a brand-new association, so these are not yet | |
1608 | * side effects--it is safe to run them here. | |
1609 | */ | |
1610 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1611 | ||
1612 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1613 | sctp_source(chunk), peer_init, | |
1614 | GFP_ATOMIC)) | |
1615 | goto nomem; | |
1616 | ||
1617 | /* Make sure no new addresses are being added during the | |
1618 | * restart. Though this is a pretty complicated attack | |
1619 | * since you'd have to get inside the cookie. | |
1620 | */ | |
1621 | if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) { | |
1622 | return SCTP_DISPOSITION_CONSUME; | |
1623 | } | |
1624 | ||
1625 | /* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes | |
1626 | * the peer has restarted (Action A), it MUST NOT setup a new | |
1627 | * association but instead resend the SHUTDOWN ACK and send an ERROR | |
1628 | * chunk with a "Cookie Received while Shutting Down" error cause to | |
1629 | * its peer. | |
1630 | */ | |
1631 | if (sctp_state(asoc, SHUTDOWN_ACK_SENT)) { | |
1632 | disposition = sctp_sf_do_9_2_reshutack(ep, asoc, | |
1633 | SCTP_ST_CHUNK(chunk->chunk_hdr->type), | |
1634 | chunk, commands); | |
1635 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
1636 | goto nomem; | |
1637 | ||
1638 | err = sctp_make_op_error(asoc, chunk, | |
1639 | SCTP_ERROR_COOKIE_IN_SHUTDOWN, | |
1640 | NULL, 0); | |
1641 | if (err) | |
1642 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
1643 | SCTP_CHUNK(err)); | |
1644 | ||
1645 | return SCTP_DISPOSITION_CONSUME; | |
1646 | } | |
1647 | ||
1648 | /* For now, fail any unsent/unacked data. Consider the optional | |
1649 | * choice of resending of this data. | |
1650 | */ | |
1651 | sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL()); | |
1652 | ||
1da177e4 LT |
1653 | repl = sctp_make_cookie_ack(new_asoc, chunk); |
1654 | if (!repl) | |
1655 | goto nomem; | |
1656 | ||
1da177e4 LT |
1657 | /* Report association restart to upper layer. */ |
1658 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0, | |
1659 | new_asoc->c.sinit_num_ostreams, | |
1660 | new_asoc->c.sinit_max_instreams, | |
a5a35e76 | 1661 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1662 | if (!ev) |
1663 | goto nomem_ev; | |
1664 | ||
df7deeb5 VY |
1665 | /* Update the content of current association. */ |
1666 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1667 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1da177e4 LT |
1668 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
1669 | return SCTP_DISPOSITION_CONSUME; | |
1670 | ||
1671 | nomem_ev: | |
1672 | sctp_chunk_free(repl); | |
1673 | nomem: | |
1674 | return SCTP_DISPOSITION_NOMEM; | |
1675 | } | |
1676 | ||
1677 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'B') | |
1678 | * | |
1679 | * Section 5.2.4 | |
1680 | * B) In this case, both sides may be attempting to start an association | |
1681 | * at about the same time but the peer endpoint started its INIT | |
1682 | * after responding to the local endpoint's INIT | |
1683 | */ | |
1684 | /* This case represents an initialization collision. */ | |
1685 | static sctp_disposition_t sctp_sf_do_dupcook_b(const struct sctp_endpoint *ep, | |
1686 | const struct sctp_association *asoc, | |
1687 | struct sctp_chunk *chunk, | |
1688 | sctp_cmd_seq_t *commands, | |
1689 | struct sctp_association *new_asoc) | |
1690 | { | |
1691 | sctp_init_chunk_t *peer_init; | |
1da177e4 LT |
1692 | struct sctp_chunk *repl; |
1693 | ||
1694 | /* new_asoc is a brand-new association, so these are not yet | |
1695 | * side effects--it is safe to run them here. | |
1696 | */ | |
1697 | peer_init = &chunk->subh.cookie_hdr->c.peer_init[0]; | |
1698 | if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type, | |
1699 | sctp_source(chunk), peer_init, | |
1700 | GFP_ATOMIC)) | |
1701 | goto nomem; | |
1702 | ||
1703 | /* Update the content of current association. */ | |
1704 | sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc)); | |
1705 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1706 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1707 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1708 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL()); | |
1709 | ||
1710 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1711 | if (!repl) | |
1712 | goto nomem; | |
1713 | ||
1714 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
1715 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL()); | |
1716 | ||
1717 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1718 | * | |
1719 | * D) IMPLEMENTATION NOTE: An implementation may choose to | |
1720 | * send the Communication Up notification to the SCTP user | |
1721 | * upon reception of a valid COOKIE ECHO chunk. | |
07d93967 VY |
1722 | * |
1723 | * Sadly, this needs to be implemented as a side-effect, because | |
1724 | * we are not guaranteed to have set the association id of the real | |
1725 | * association and so these notifications need to be delayed until | |
1726 | * the association id is allocated. | |
1da177e4 | 1727 | */ |
1da177e4 | 1728 | |
07d93967 | 1729 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_CHANGE, SCTP_U8(SCTP_COMM_UP)); |
1da177e4 LT |
1730 | |
1731 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1732 | * When a peer sends a Adaptation Layer Indication parameter , SCTP |
1da177e4 | 1733 | * delivers this notification to inform the application that of the |
0f3fffd8 | 1734 | * peers requested adaptation layer. |
07d93967 VY |
1735 | * |
1736 | * This also needs to be done as a side effect for the same reason as | |
1737 | * above. | |
1da177e4 | 1738 | */ |
07d93967 VY |
1739 | if (asoc->peer.adaptation_ind) |
1740 | sctp_add_cmd_sf(commands, SCTP_CMD_ADAPTATION_IND, SCTP_NULL()); | |
1da177e4 LT |
1741 | |
1742 | return SCTP_DISPOSITION_CONSUME; | |
1743 | ||
1da177e4 LT |
1744 | nomem: |
1745 | return SCTP_DISPOSITION_NOMEM; | |
1746 | } | |
1747 | ||
1748 | /* Unexpected COOKIE-ECHO handler for setup collision (Table 2, action 'C') | |
1749 | * | |
1750 | * Section 5.2.4 | |
1751 | * C) In this case, the local endpoint's cookie has arrived late. | |
1752 | * Before it arrived, the local endpoint sent an INIT and received an | |
1753 | * INIT-ACK and finally sent a COOKIE ECHO with the peer's same tag | |
1754 | * but a new tag of its own. | |
1755 | */ | |
1756 | /* This case represents an initialization collision. */ | |
1757 | static sctp_disposition_t sctp_sf_do_dupcook_c(const struct sctp_endpoint *ep, | |
1758 | const struct sctp_association *asoc, | |
1759 | struct sctp_chunk *chunk, | |
1760 | sctp_cmd_seq_t *commands, | |
1761 | struct sctp_association *new_asoc) | |
1762 | { | |
1763 | /* The cookie should be silently discarded. | |
1764 | * The endpoint SHOULD NOT change states and should leave | |
1765 | * any timers running. | |
1766 | */ | |
1767 | return SCTP_DISPOSITION_DISCARD; | |
1768 | } | |
1769 | ||
1770 | /* Unexpected COOKIE-ECHO handler lost chunk (Table 2, action 'D') | |
1771 | * | |
1772 | * Section 5.2.4 | |
1773 | * | |
1774 | * D) When both local and remote tags match the endpoint should always | |
1775 | * enter the ESTABLISHED state, if it has not already done so. | |
1776 | */ | |
1777 | /* This case represents an initialization collision. */ | |
1778 | static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep, | |
1779 | const struct sctp_association *asoc, | |
1780 | struct sctp_chunk *chunk, | |
1781 | sctp_cmd_seq_t *commands, | |
1782 | struct sctp_association *new_asoc) | |
1783 | { | |
df7deeb5 | 1784 | struct sctp_ulpevent *ev = NULL, *ai_ev = NULL; |
1da177e4 LT |
1785 | struct sctp_chunk *repl; |
1786 | ||
1787 | /* Clarification from Implementor's Guide: | |
1788 | * D) When both local and remote tags match the endpoint should | |
d808ad9a YH |
1789 | * enter the ESTABLISHED state, if it is in the COOKIE-ECHOED state. |
1790 | * It should stop any cookie timer that may be running and send | |
1791 | * a COOKIE ACK. | |
1da177e4 LT |
1792 | */ |
1793 | ||
1794 | /* Don't accidentally move back into established state. */ | |
1795 | if (asoc->state < SCTP_STATE_ESTABLISHED) { | |
1796 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
1797 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
1798 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
1799 | SCTP_STATE(SCTP_STATE_ESTABLISHED)); | |
1800 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
1801 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, | |
1802 | SCTP_NULL()); | |
1803 | ||
1804 | /* RFC 2960 5.1 Normal Establishment of an Association | |
1805 | * | |
1806 | * D) IMPLEMENTATION NOTE: An implementation may choose | |
1807 | * to send the Communication Up notification to the | |
1808 | * SCTP user upon reception of a valid COOKIE | |
1809 | * ECHO chunk. | |
1810 | */ | |
df7deeb5 | 1811 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, |
1da177e4 | 1812 | SCTP_COMM_UP, 0, |
df7deeb5 VY |
1813 | asoc->c.sinit_num_ostreams, |
1814 | asoc->c.sinit_max_instreams, | |
9cbcbf4e | 1815 | NULL, GFP_ATOMIC); |
1da177e4 LT |
1816 | if (!ev) |
1817 | goto nomem; | |
1da177e4 LT |
1818 | |
1819 | /* Sockets API Draft Section 5.3.1.6 | |
0f3fffd8 | 1820 | * When a peer sends a Adaptation Layer Indication parameter, |
1da177e4 | 1821 | * SCTP delivers this notification to inform the application |
0f3fffd8 | 1822 | * that of the peers requested adaptation layer. |
1da177e4 | 1823 | */ |
0f3fffd8 ISJ |
1824 | if (asoc->peer.adaptation_ind) { |
1825 | ai_ev = sctp_ulpevent_make_adaptation_indication(asoc, | |
1da177e4 | 1826 | GFP_ATOMIC); |
df7deeb5 | 1827 | if (!ai_ev) |
1da177e4 LT |
1828 | goto nomem; |
1829 | ||
1da177e4 LT |
1830 | } |
1831 | } | |
1832 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL()); | |
1833 | ||
1834 | repl = sctp_make_cookie_ack(new_asoc, chunk); | |
1835 | if (!repl) | |
1836 | goto nomem; | |
1837 | ||
df7deeb5 VY |
1838 | if (ev) |
1839 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1840 | SCTP_ULPEVENT(ev)); | |
1841 | if (ai_ev) | |
1842 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, | |
1843 | SCTP_ULPEVENT(ai_ev)); | |
1844 | ||
1da177e4 LT |
1845 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
1846 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL()); | |
1847 | ||
1848 | return SCTP_DISPOSITION_CONSUME; | |
1849 | ||
1850 | nomem: | |
df7deeb5 VY |
1851 | if (ai_ev) |
1852 | sctp_ulpevent_free(ai_ev); | |
1da177e4 LT |
1853 | if (ev) |
1854 | sctp_ulpevent_free(ev); | |
1855 | return SCTP_DISPOSITION_NOMEM; | |
1856 | } | |
1857 | ||
1858 | /* | |
1859 | * Handle a duplicate COOKIE-ECHO. This usually means a cookie-carrying | |
1860 | * chunk was retransmitted and then delayed in the network. | |
1861 | * | |
1862 | * Section: 5.2.4 Handle a COOKIE ECHO when a TCB exists | |
1863 | * | |
1864 | * Verification Tag: None. Do cookie validation. | |
1865 | * | |
1866 | * Inputs | |
1867 | * (endpoint, asoc, chunk) | |
1868 | * | |
1869 | * Outputs | |
1870 | * (asoc, reply_msg, msg_up, timers, counters) | |
1871 | * | |
1872 | * The return value is the disposition of the chunk. | |
1873 | */ | |
1874 | sctp_disposition_t sctp_sf_do_5_2_4_dupcook(const struct sctp_endpoint *ep, | |
1875 | const struct sctp_association *asoc, | |
1876 | const sctp_subtype_t type, | |
1877 | void *arg, | |
1878 | sctp_cmd_seq_t *commands) | |
1879 | { | |
1880 | sctp_disposition_t retval; | |
1881 | struct sctp_chunk *chunk = arg; | |
1882 | struct sctp_association *new_asoc; | |
1883 | int error = 0; | |
1884 | char action; | |
1885 | struct sctp_chunk *err_chk_p; | |
1886 | ||
1887 | /* Make sure that the chunk has a valid length from the protocol | |
1888 | * perspective. In this case check to make sure we have at least | |
1889 | * enough for the chunk header. Cookie length verification is | |
1890 | * done later. | |
1891 | */ | |
1892 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
1893 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
1894 | commands); | |
1895 | ||
1896 | /* "Decode" the chunk. We have no optional parameters so we | |
1897 | * are in good shape. | |
1898 | */ | |
d808ad9a | 1899 | chunk->subh.cookie_hdr = (struct sctp_signed_cookie *)chunk->skb->data; |
62b08083 SS |
1900 | if (!pskb_pull(chunk->skb, ntohs(chunk->chunk_hdr->length) - |
1901 | sizeof(sctp_chunkhdr_t))) | |
1902 | goto nomem; | |
1da177e4 LT |
1903 | |
1904 | /* In RFC 2960 5.2.4 3, if both Verification Tags in the State Cookie | |
1905 | * of a duplicate COOKIE ECHO match the Verification Tags of the | |
1906 | * current association, consider the State Cookie valid even if | |
1907 | * the lifespan is exceeded. | |
1908 | */ | |
1909 | new_asoc = sctp_unpack_cookie(ep, asoc, chunk, GFP_ATOMIC, &error, | |
1910 | &err_chk_p); | |
1911 | ||
1912 | /* FIXME: | |
1913 | * If the re-build failed, what is the proper error path | |
1914 | * from here? | |
1915 | * | |
1916 | * [We should abort the association. --piggy] | |
1917 | */ | |
1918 | if (!new_asoc) { | |
1919 | /* FIXME: Several errors are possible. A bad cookie should | |
1920 | * be silently discarded, but think about logging it too. | |
1921 | */ | |
1922 | switch (error) { | |
1923 | case -SCTP_IERROR_NOMEM: | |
1924 | goto nomem; | |
1925 | ||
1926 | case -SCTP_IERROR_STALE_COOKIE: | |
1927 | sctp_send_stale_cookie_err(ep, asoc, chunk, commands, | |
1928 | err_chk_p); | |
1929 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1930 | case -SCTP_IERROR_BAD_SIG: | |
1931 | default: | |
1932 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3ff50b79 | 1933 | } |
1da177e4 LT |
1934 | } |
1935 | ||
1936 | /* Compare the tie_tag in cookie with the verification tag of | |
1937 | * current association. | |
1938 | */ | |
1939 | action = sctp_tietags_compare(new_asoc, asoc); | |
1940 | ||
1941 | switch (action) { | |
1942 | case 'A': /* Association restart. */ | |
1943 | retval = sctp_sf_do_dupcook_a(ep, asoc, chunk, commands, | |
1944 | new_asoc); | |
1945 | break; | |
1946 | ||
1947 | case 'B': /* Collision case B. */ | |
1948 | retval = sctp_sf_do_dupcook_b(ep, asoc, chunk, commands, | |
1949 | new_asoc); | |
1950 | break; | |
1951 | ||
1952 | case 'C': /* Collision case C. */ | |
1953 | retval = sctp_sf_do_dupcook_c(ep, asoc, chunk, commands, | |
1954 | new_asoc); | |
1955 | break; | |
1956 | ||
1957 | case 'D': /* Collision case D. */ | |
1958 | retval = sctp_sf_do_dupcook_d(ep, asoc, chunk, commands, | |
1959 | new_asoc); | |
1960 | break; | |
1961 | ||
1962 | default: /* Discard packet for all others. */ | |
1963 | retval = sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1964 | break; | |
3ff50b79 | 1965 | } |
1da177e4 LT |
1966 | |
1967 | /* Delete the tempory new association. */ | |
1968 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc)); | |
1969 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
1970 | ||
1971 | return retval; | |
1972 | ||
1973 | nomem: | |
1974 | return SCTP_DISPOSITION_NOMEM; | |
1975 | } | |
1976 | ||
1977 | /* | |
1978 | * Process an ABORT. (SHUTDOWN-PENDING state) | |
1979 | * | |
1980 | * See sctp_sf_do_9_1_abort(). | |
1981 | */ | |
1982 | sctp_disposition_t sctp_sf_shutdown_pending_abort( | |
1983 | const struct sctp_endpoint *ep, | |
1984 | const struct sctp_association *asoc, | |
1985 | const sctp_subtype_t type, | |
1986 | void *arg, | |
1987 | sctp_cmd_seq_t *commands) | |
1988 | { | |
1989 | struct sctp_chunk *chunk = arg; | |
1990 | ||
1991 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
1992 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1993 | ||
1994 | /* Make sure that the ABORT chunk has a valid length. | |
1995 | * Since this is an ABORT chunk, we have to discard it | |
1996 | * because of the following text: | |
1997 | * RFC 2960, Section 3.3.7 | |
1998 | * If an endpoint receives an ABORT with a format error or for an | |
1999 | * association that doesn't exist, it MUST silently discard it. | |
2000 | * Becasue the length is "invalid", we can't really discard just | |
2001 | * as we do not know its true length. So, to be safe, discard the | |
2002 | * packet. | |
2003 | */ | |
2004 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2005 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2006 | ||
2007 | /* Stop the T5-shutdown guard timer. */ | |
2008 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2009 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2010 | ||
2011 | return sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); | |
2012 | } | |
2013 | ||
2014 | /* | |
2015 | * Process an ABORT. (SHUTDOWN-SENT state) | |
2016 | * | |
2017 | * See sctp_sf_do_9_1_abort(). | |
2018 | */ | |
2019 | sctp_disposition_t sctp_sf_shutdown_sent_abort(const struct sctp_endpoint *ep, | |
2020 | const struct sctp_association *asoc, | |
2021 | const sctp_subtype_t type, | |
2022 | void *arg, | |
2023 | sctp_cmd_seq_t *commands) | |
2024 | { | |
2025 | struct sctp_chunk *chunk = arg; | |
2026 | ||
2027 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2028 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2029 | ||
2030 | /* Make sure that the ABORT chunk has a valid length. | |
2031 | * Since this is an ABORT chunk, we have to discard it | |
2032 | * because of the following text: | |
2033 | * RFC 2960, Section 3.3.7 | |
2034 | * If an endpoint receives an ABORT with a format error or for an | |
2035 | * association that doesn't exist, it MUST silently discard it. | |
2036 | * Becasue the length is "invalid", we can't really discard just | |
2037 | * as we do not know its true length. So, to be safe, discard the | |
2038 | * packet. | |
2039 | */ | |
2040 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2041 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2042 | ||
2043 | /* Stop the T2-shutdown timer. */ | |
2044 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2045 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2046 | ||
2047 | /* Stop the T5-shutdown guard timer. */ | |
2048 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2049 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
2050 | ||
2051 | return sctp_sf_do_9_1_abort(ep, asoc, type, arg, commands); | |
2052 | } | |
2053 | ||
2054 | /* | |
2055 | * Process an ABORT. (SHUTDOWN-ACK-SENT state) | |
2056 | * | |
2057 | * See sctp_sf_do_9_1_abort(). | |
2058 | */ | |
2059 | sctp_disposition_t sctp_sf_shutdown_ack_sent_abort( | |
2060 | const struct sctp_endpoint *ep, | |
2061 | const struct sctp_association *asoc, | |
2062 | const sctp_subtype_t type, | |
2063 | void *arg, | |
2064 | sctp_cmd_seq_t *commands) | |
2065 | { | |
2066 | /* The same T2 timer, so we should be able to use | |
2067 | * common function with the SHUTDOWN-SENT state. | |
2068 | */ | |
2069 | return sctp_sf_shutdown_sent_abort(ep, asoc, type, arg, commands); | |
2070 | } | |
2071 | ||
2072 | /* | |
2073 | * Handle an Error received in COOKIE_ECHOED state. | |
2074 | * | |
2075 | * Only handle the error type of stale COOKIE Error, the other errors will | |
2076 | * be ignored. | |
2077 | * | |
2078 | * Inputs | |
2079 | * (endpoint, asoc, chunk) | |
2080 | * | |
2081 | * Outputs | |
2082 | * (asoc, reply_msg, msg_up, timers, counters) | |
2083 | * | |
2084 | * The return value is the disposition of the chunk. | |
2085 | */ | |
2086 | sctp_disposition_t sctp_sf_cookie_echoed_err(const struct sctp_endpoint *ep, | |
2087 | const struct sctp_association *asoc, | |
2088 | const sctp_subtype_t type, | |
2089 | void *arg, | |
2090 | sctp_cmd_seq_t *commands) | |
2091 | { | |
2092 | struct sctp_chunk *chunk = arg; | |
2093 | sctp_errhdr_t *err; | |
2094 | ||
2095 | if (!sctp_vtag_verify(chunk, asoc)) | |
2096 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2097 | ||
2098 | /* Make sure that the ERROR chunk has a valid length. | |
2099 | * The parameter walking depends on this as well. | |
2100 | */ | |
2101 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
2102 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2103 | commands); | |
2104 | ||
2105 | /* Process the error here */ | |
2106 | /* FUTURE FIXME: When PR-SCTP related and other optional | |
2107 | * parms are emitted, this will have to change to handle multiple | |
2108 | * errors. | |
2109 | */ | |
2110 | sctp_walk_errors(err, chunk->chunk_hdr) { | |
2111 | if (SCTP_ERROR_STALE_COOKIE == err->cause) | |
d808ad9a | 2112 | return sctp_sf_do_5_2_6_stale(ep, asoc, type, |
1da177e4 LT |
2113 | arg, commands); |
2114 | } | |
2115 | ||
2116 | /* It is possible to have malformed error causes, and that | |
2117 | * will cause us to end the walk early. However, since | |
2118 | * we are discarding the packet, there should be no adverse | |
2119 | * affects. | |
2120 | */ | |
2121 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2122 | } | |
2123 | ||
2124 | /* | |
2125 | * Handle a Stale COOKIE Error | |
2126 | * | |
2127 | * Section: 5.2.6 Handle Stale COOKIE Error | |
2128 | * If the association is in the COOKIE-ECHOED state, the endpoint may elect | |
2129 | * one of the following three alternatives. | |
2130 | * ... | |
2131 | * 3) Send a new INIT chunk to the endpoint, adding a Cookie | |
2132 | * Preservative parameter requesting an extension to the lifetime of | |
2133 | * the State Cookie. When calculating the time extension, an | |
2134 | * implementation SHOULD use the RTT information measured based on the | |
2135 | * previous COOKIE ECHO / ERROR exchange, and should add no more | |
2136 | * than 1 second beyond the measured RTT, due to long State Cookie | |
2137 | * lifetimes making the endpoint more subject to a replay attack. | |
2138 | * | |
2139 | * Verification Tag: Not explicit, but safe to ignore. | |
2140 | * | |
2141 | * Inputs | |
2142 | * (endpoint, asoc, chunk) | |
2143 | * | |
2144 | * Outputs | |
2145 | * (asoc, reply_msg, msg_up, timers, counters) | |
2146 | * | |
2147 | * The return value is the disposition of the chunk. | |
2148 | */ | |
2149 | static sctp_disposition_t sctp_sf_do_5_2_6_stale(const struct sctp_endpoint *ep, | |
2150 | const struct sctp_association *asoc, | |
2151 | const sctp_subtype_t type, | |
2152 | void *arg, | |
2153 | sctp_cmd_seq_t *commands) | |
2154 | { | |
2155 | struct sctp_chunk *chunk = arg; | |
2156 | time_t stale; | |
2157 | sctp_cookie_preserve_param_t bht; | |
2158 | sctp_errhdr_t *err; | |
2159 | struct sctp_chunk *reply; | |
2160 | struct sctp_bind_addr *bp; | |
3f7a87d2 | 2161 | int attempts = asoc->init_err_counter + 1; |
1da177e4 | 2162 | |
81845c21 | 2163 | if (attempts > asoc->max_init_attempts) { |
8de8c873 SS |
2164 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
2165 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 2166 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 2167 | SCTP_PERR(SCTP_ERROR_STALE_COOKIE)); |
1da177e4 LT |
2168 | return SCTP_DISPOSITION_DELETE_TCB; |
2169 | } | |
2170 | ||
2171 | err = (sctp_errhdr_t *)(chunk->skb->data); | |
2172 | ||
2173 | /* When calculating the time extension, an implementation | |
2174 | * SHOULD use the RTT information measured based on the | |
2175 | * previous COOKIE ECHO / ERROR exchange, and should add no | |
2176 | * more than 1 second beyond the measured RTT, due to long | |
2177 | * State Cookie lifetimes making the endpoint more subject to | |
2178 | * a replay attack. | |
2179 | * Measure of Staleness's unit is usec. (1/1000000 sec) | |
2180 | * Suggested Cookie Life-span Increment's unit is msec. | |
2181 | * (1/1000 sec) | |
2182 | * In general, if you use the suggested cookie life, the value | |
2183 | * found in the field of measure of staleness should be doubled | |
2184 | * to give ample time to retransmit the new cookie and thus | |
2185 | * yield a higher probability of success on the reattempt. | |
2186 | */ | |
34bcca28 | 2187 | stale = ntohl(*(__be32 *)((u8 *)err + sizeof(sctp_errhdr_t))); |
1da177e4 LT |
2188 | stale = (stale * 2) / 1000; |
2189 | ||
2190 | bht.param_hdr.type = SCTP_PARAM_COOKIE_PRESERVATIVE; | |
2191 | bht.param_hdr.length = htons(sizeof(bht)); | |
2192 | bht.lifespan_increment = htonl(stale); | |
2193 | ||
2194 | /* Build that new INIT chunk. */ | |
2195 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; | |
2196 | reply = sctp_make_init(asoc, bp, GFP_ATOMIC, sizeof(bht)); | |
2197 | if (!reply) | |
2198 | goto nomem; | |
2199 | ||
2200 | sctp_addto_chunk(reply, sizeof(bht), &bht); | |
2201 | ||
2202 | /* Clear peer's init_tag cached in assoc as we are sending a new INIT */ | |
2203 | sctp_add_cmd_sf(commands, SCTP_CMD_CLEAR_INIT_TAG, SCTP_NULL()); | |
2204 | ||
2205 | /* Stop pending T3-rtx and heartbeat timers */ | |
2206 | sctp_add_cmd_sf(commands, SCTP_CMD_T3_RTX_TIMERS_STOP, SCTP_NULL()); | |
2207 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
2208 | ||
2209 | /* Delete non-primary peer ip addresses since we are transitioning | |
2210 | * back to the COOKIE-WAIT state | |
2211 | */ | |
2212 | sctp_add_cmd_sf(commands, SCTP_CMD_DEL_NON_PRIMARY, SCTP_NULL()); | |
2213 | ||
d808ad9a YH |
2214 | /* If we've sent any data bundled with COOKIE-ECHO we will need to |
2215 | * resend | |
1da177e4 | 2216 | */ |
d808ad9a | 2217 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, |
1da177e4 LT |
2218 | SCTP_TRANSPORT(asoc->peer.primary_path)); |
2219 | ||
2220 | /* Cast away the const modifier, as we want to just | |
2221 | * rerun it through as a sideffect. | |
2222 | */ | |
3f7a87d2 | 2223 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_INC, SCTP_NULL()); |
1da177e4 LT |
2224 | |
2225 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2226 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
2227 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2228 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
2229 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
2230 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
2231 | ||
2232 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2233 | ||
2234 | return SCTP_DISPOSITION_CONSUME; | |
2235 | ||
2236 | nomem: | |
2237 | return SCTP_DISPOSITION_NOMEM; | |
2238 | } | |
2239 | ||
2240 | /* | |
2241 | * Process an ABORT. | |
2242 | * | |
2243 | * Section: 9.1 | |
2244 | * After checking the Verification Tag, the receiving endpoint shall | |
2245 | * remove the association from its record, and shall report the | |
2246 | * termination to its upper layer. | |
2247 | * | |
2248 | * Verification Tag: 8.5.1 Exceptions in Verification Tag Rules | |
2249 | * B) Rules for packet carrying ABORT: | |
2250 | * | |
2251 | * - The endpoint shall always fill in the Verification Tag field of the | |
2252 | * outbound packet with the destination endpoint's tag value if it | |
2253 | * is known. | |
2254 | * | |
2255 | * - If the ABORT is sent in response to an OOTB packet, the endpoint | |
2256 | * MUST follow the procedure described in Section 8.4. | |
2257 | * | |
2258 | * - The receiver MUST accept the packet if the Verification Tag | |
2259 | * matches either its own tag, OR the tag of its peer. Otherwise, the | |
2260 | * receiver MUST silently discard the packet and take no further | |
2261 | * action. | |
2262 | * | |
2263 | * Inputs | |
2264 | * (endpoint, asoc, chunk) | |
2265 | * | |
2266 | * Outputs | |
2267 | * (asoc, reply_msg, msg_up, timers, counters) | |
2268 | * | |
2269 | * The return value is the disposition of the chunk. | |
2270 | */ | |
2271 | sctp_disposition_t sctp_sf_do_9_1_abort(const struct sctp_endpoint *ep, | |
2272 | const struct sctp_association *asoc, | |
2273 | const sctp_subtype_t type, | |
2274 | void *arg, | |
2275 | sctp_cmd_seq_t *commands) | |
2276 | { | |
2277 | struct sctp_chunk *chunk = arg; | |
2278 | unsigned len; | |
5be291fe | 2279 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 LT |
2280 | |
2281 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2282 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2283 | ||
2284 | /* Make sure that the ABORT chunk has a valid length. | |
2285 | * Since this is an ABORT chunk, we have to discard it | |
2286 | * because of the following text: | |
2287 | * RFC 2960, Section 3.3.7 | |
2288 | * If an endpoint receives an ABORT with a format error or for an | |
2289 | * association that doesn't exist, it MUST silently discard it. | |
2290 | * Becasue the length is "invalid", we can't really discard just | |
2291 | * as we do not know its true length. So, to be safe, discard the | |
2292 | * packet. | |
2293 | */ | |
2294 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2295 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2296 | ||
2297 | /* See if we have an error cause code in the chunk. */ | |
2298 | len = ntohs(chunk->chunk_hdr->length); | |
2299 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2300 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2301 | ||
8de8c873 | 2302 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(ECONNRESET)); |
d808ad9a | 2303 | /* ASSOC_FAILED will DELETE_TCB. */ |
5be291fe | 2304 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, SCTP_PERR(error)); |
1da177e4 LT |
2305 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
2306 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
2307 | ||
2308 | return SCTP_DISPOSITION_ABORT; | |
2309 | } | |
2310 | ||
2311 | /* | |
2312 | * Process an ABORT. (COOKIE-WAIT state) | |
2313 | * | |
2314 | * See sctp_sf_do_9_1_abort() above. | |
2315 | */ | |
2316 | sctp_disposition_t sctp_sf_cookie_wait_abort(const struct sctp_endpoint *ep, | |
2317 | const struct sctp_association *asoc, | |
2318 | const sctp_subtype_t type, | |
2319 | void *arg, | |
2320 | sctp_cmd_seq_t *commands) | |
2321 | { | |
2322 | struct sctp_chunk *chunk = arg; | |
2323 | unsigned len; | |
f94c0198 | 2324 | __be16 error = SCTP_ERROR_NO_ERROR; |
1da177e4 LT |
2325 | |
2326 | if (!sctp_vtag_verify_either(chunk, asoc)) | |
2327 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2328 | ||
2329 | /* Make sure that the ABORT chunk has a valid length. | |
2330 | * Since this is an ABORT chunk, we have to discard it | |
2331 | * because of the following text: | |
2332 | * RFC 2960, Section 3.3.7 | |
2333 | * If an endpoint receives an ABORT with a format error or for an | |
2334 | * association that doesn't exist, it MUST silently discard it. | |
2335 | * Becasue the length is "invalid", we can't really discard just | |
2336 | * as we do not know its true length. So, to be safe, discard the | |
2337 | * packet. | |
2338 | */ | |
2339 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_abort_chunk_t))) | |
2340 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2341 | ||
2342 | /* See if we have an error cause code in the chunk. */ | |
2343 | len = ntohs(chunk->chunk_hdr->length); | |
2344 | if (len >= sizeof(struct sctp_chunkhdr) + sizeof(struct sctp_errhdr)) | |
2345 | error = ((sctp_errhdr_t *)chunk->skb->data)->cause; | |
2346 | ||
8de8c873 SS |
2347 | return sctp_stop_t1_and_abort(commands, error, ECONNREFUSED, asoc, |
2348 | chunk->transport); | |
1da177e4 LT |
2349 | } |
2350 | ||
2351 | /* | |
2352 | * Process an incoming ICMP as an ABORT. (COOKIE-WAIT state) | |
2353 | */ | |
2354 | sctp_disposition_t sctp_sf_cookie_wait_icmp_abort(const struct sctp_endpoint *ep, | |
2355 | const struct sctp_association *asoc, | |
2356 | const sctp_subtype_t type, | |
2357 | void *arg, | |
2358 | sctp_cmd_seq_t *commands) | |
2359 | { | |
8de8c873 SS |
2360 | return sctp_stop_t1_and_abort(commands, SCTP_ERROR_NO_ERROR, |
2361 | ENOPROTOOPT, asoc, | |
3f7a87d2 | 2362 | (struct sctp_transport *)arg); |
1da177e4 LT |
2363 | } |
2364 | ||
2365 | /* | |
2366 | * Process an ABORT. (COOKIE-ECHOED state) | |
2367 | */ | |
2368 | sctp_disposition_t sctp_sf_cookie_echoed_abort(const struct sctp_endpoint *ep, | |
2369 | const struct sctp_association *asoc, | |
2370 | const sctp_subtype_t type, | |
2371 | void *arg, | |
2372 | sctp_cmd_seq_t *commands) | |
2373 | { | |
2374 | /* There is a single T1 timer, so we should be able to use | |
2375 | * common function with the COOKIE-WAIT state. | |
2376 | */ | |
2377 | return sctp_sf_cookie_wait_abort(ep, asoc, type, arg, commands); | |
2378 | } | |
2379 | ||
2380 | /* | |
2381 | * Stop T1 timer and abort association with "INIT failed". | |
2382 | * | |
2383 | * This is common code called by several sctp_sf_*_abort() functions above. | |
2384 | */ | |
52c1da39 | 2385 | static sctp_disposition_t sctp_stop_t1_and_abort(sctp_cmd_seq_t *commands, |
f94c0198 | 2386 | __be16 error, int sk_err, |
3f7a87d2 FF |
2387 | const struct sctp_association *asoc, |
2388 | struct sctp_transport *transport) | |
1da177e4 | 2389 | { |
3f7a87d2 | 2390 | SCTP_DEBUG_PRINTK("ABORT received (INIT).\n"); |
1da177e4 LT |
2391 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
2392 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
2393 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
2394 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
2395 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
8de8c873 | 2396 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, SCTP_ERROR(sk_err)); |
1da177e4 LT |
2397 | /* CMD_INIT_FAILED will DELETE_TCB. */ |
2398 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 2399 | SCTP_PERR(error)); |
3f7a87d2 | 2400 | return SCTP_DISPOSITION_ABORT; |
1da177e4 LT |
2401 | } |
2402 | ||
2403 | /* | |
2404 | * sctp_sf_do_9_2_shut | |
2405 | * | |
2406 | * Section: 9.2 | |
2407 | * Upon the reception of the SHUTDOWN, the peer endpoint shall | |
2408 | * - enter the SHUTDOWN-RECEIVED state, | |
2409 | * | |
2410 | * - stop accepting new data from its SCTP user | |
2411 | * | |
2412 | * - verify, by checking the Cumulative TSN Ack field of the chunk, | |
2413 | * that all its outstanding DATA chunks have been received by the | |
2414 | * SHUTDOWN sender. | |
2415 | * | |
2416 | * Once an endpoint as reached the SHUTDOWN-RECEIVED state it MUST NOT | |
2417 | * send a SHUTDOWN in response to a ULP request. And should discard | |
2418 | * subsequent SHUTDOWN chunks. | |
2419 | * | |
2420 | * If there are still outstanding DATA chunks left, the SHUTDOWN | |
2421 | * receiver shall continue to follow normal data transmission | |
2422 | * procedures defined in Section 6 until all outstanding DATA chunks | |
2423 | * are acknowledged; however, the SHUTDOWN receiver MUST NOT accept | |
2424 | * new data from its SCTP user. | |
2425 | * | |
2426 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2427 | * | |
2428 | * Inputs | |
2429 | * (endpoint, asoc, chunk) | |
2430 | * | |
2431 | * Outputs | |
2432 | * (asoc, reply_msg, msg_up, timers, counters) | |
2433 | * | |
2434 | * The return value is the disposition of the chunk. | |
2435 | */ | |
2436 | sctp_disposition_t sctp_sf_do_9_2_shutdown(const struct sctp_endpoint *ep, | |
2437 | const struct sctp_association *asoc, | |
2438 | const sctp_subtype_t type, | |
2439 | void *arg, | |
2440 | sctp_cmd_seq_t *commands) | |
2441 | { | |
2442 | struct sctp_chunk *chunk = arg; | |
2443 | sctp_shutdownhdr_t *sdh; | |
2444 | sctp_disposition_t disposition; | |
2445 | struct sctp_ulpevent *ev; | |
2446 | ||
2447 | if (!sctp_vtag_verify(chunk, asoc)) | |
2448 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2449 | ||
2450 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
2451 | if (!sctp_chunk_length_valid(chunk, | |
2452 | sizeof(struct sctp_shutdown_chunk_t))) | |
2453 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2454 | commands); | |
2455 | ||
2456 | /* Convert the elaborate header. */ | |
2457 | sdh = (sctp_shutdownhdr_t *)chunk->skb->data; | |
2458 | skb_pull(chunk->skb, sizeof(sctp_shutdownhdr_t)); | |
2459 | chunk->subh.shutdown_hdr = sdh; | |
2460 | ||
eb0e0076 SS |
2461 | /* API 5.3.1.5 SCTP_SHUTDOWN_EVENT |
2462 | * When a peer sends a SHUTDOWN, SCTP delivers this notification to | |
2463 | * inform the application that it should cease sending data. | |
2464 | */ | |
2465 | ev = sctp_ulpevent_make_shutdown_event(asoc, 0, GFP_ATOMIC); | |
2466 | if (!ev) { | |
2467 | disposition = SCTP_DISPOSITION_NOMEM; | |
d808ad9a | 2468 | goto out; |
eb0e0076 SS |
2469 | } |
2470 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); | |
2471 | ||
1da177e4 LT |
2472 | /* Upon the reception of the SHUTDOWN, the peer endpoint shall |
2473 | * - enter the SHUTDOWN-RECEIVED state, | |
2474 | * - stop accepting new data from its SCTP user | |
2475 | * | |
2476 | * [This is implicit in the new state.] | |
2477 | */ | |
2478 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
2479 | SCTP_STATE(SCTP_STATE_SHUTDOWN_RECEIVED)); | |
2480 | disposition = SCTP_DISPOSITION_CONSUME; | |
2481 | ||
2482 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
2483 | disposition = sctp_sf_do_9_2_shutdown_ack(ep, asoc, type, | |
2484 | arg, commands); | |
2485 | } | |
2486 | ||
2487 | if (SCTP_DISPOSITION_NOMEM == disposition) | |
2488 | goto out; | |
2489 | ||
2490 | /* - verify, by checking the Cumulative TSN Ack field of the | |
2491 | * chunk, that all its outstanding DATA chunks have been | |
2492 | * received by the SHUTDOWN sender. | |
2493 | */ | |
2494 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_CTSN, | |
2178eda8 | 2495 | SCTP_BE32(chunk->subh.shutdown_hdr->cum_tsn_ack)); |
1da177e4 | 2496 | |
1da177e4 LT |
2497 | out: |
2498 | return disposition; | |
2499 | } | |
2500 | ||
2501 | /* RFC 2960 9.2 | |
2502 | * If an endpoint is in SHUTDOWN-ACK-SENT state and receives an INIT chunk | |
2503 | * (e.g., if the SHUTDOWN COMPLETE was lost) with source and destination | |
2504 | * transport addresses (either in the IP addresses or in the INIT chunk) | |
2505 | * that belong to this association, it should discard the INIT chunk and | |
2506 | * retransmit the SHUTDOWN ACK chunk. | |
2507 | */ | |
2508 | sctp_disposition_t sctp_sf_do_9_2_reshutack(const struct sctp_endpoint *ep, | |
2509 | const struct sctp_association *asoc, | |
2510 | const sctp_subtype_t type, | |
2511 | void *arg, | |
2512 | sctp_cmd_seq_t *commands) | |
2513 | { | |
2514 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
2515 | struct sctp_chunk *reply; | |
2516 | ||
ece25dfa VY |
2517 | /* Make sure that the chunk has a valid length */ |
2518 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
2519 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2520 | commands); | |
2521 | ||
1da177e4 LT |
2522 | /* Since we are not going to really process this INIT, there |
2523 | * is no point in verifying chunk boundries. Just generate | |
2524 | * the SHUTDOWN ACK. | |
2525 | */ | |
2526 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
2527 | if (NULL == reply) | |
2528 | goto nomem; | |
2529 | ||
2530 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
2531 | * the T2-SHUTDOWN timer. | |
2532 | */ | |
2533 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
2534 | ||
2535 | /* and restart the T2-shutdown timer. */ | |
2536 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2537 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2538 | ||
2539 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
2540 | ||
2541 | return SCTP_DISPOSITION_CONSUME; | |
2542 | nomem: | |
2543 | return SCTP_DISPOSITION_NOMEM; | |
2544 | } | |
2545 | ||
2546 | /* | |
2547 | * sctp_sf_do_ecn_cwr | |
2548 | * | |
2549 | * Section: Appendix A: Explicit Congestion Notification | |
2550 | * | |
2551 | * CWR: | |
2552 | * | |
2553 | * RFC 2481 details a specific bit for a sender to send in the header of | |
2554 | * its next outbound TCP segment to indicate to its peer that it has | |
2555 | * reduced its congestion window. This is termed the CWR bit. For | |
2556 | * SCTP the same indication is made by including the CWR chunk. | |
2557 | * This chunk contains one data element, i.e. the TSN number that | |
2558 | * was sent in the ECNE chunk. This element represents the lowest | |
2559 | * TSN number in the datagram that was originally marked with the | |
2560 | * CE bit. | |
2561 | * | |
2562 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2563 | * Inputs | |
2564 | * (endpoint, asoc, chunk) | |
2565 | * | |
2566 | * Outputs | |
2567 | * (asoc, reply_msg, msg_up, timers, counters) | |
2568 | * | |
2569 | * The return value is the disposition of the chunk. | |
2570 | */ | |
2571 | sctp_disposition_t sctp_sf_do_ecn_cwr(const struct sctp_endpoint *ep, | |
2572 | const struct sctp_association *asoc, | |
2573 | const sctp_subtype_t type, | |
2574 | void *arg, | |
2575 | sctp_cmd_seq_t *commands) | |
2576 | { | |
2577 | sctp_cwrhdr_t *cwr; | |
2578 | struct sctp_chunk *chunk = arg; | |
34bcca28 | 2579 | u32 lowest_tsn; |
1da177e4 LT |
2580 | |
2581 | if (!sctp_vtag_verify(chunk, asoc)) | |
2582 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2583 | ||
2584 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2585 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2586 | commands); | |
d808ad9a | 2587 | |
1da177e4 LT |
2588 | cwr = (sctp_cwrhdr_t *) chunk->skb->data; |
2589 | skb_pull(chunk->skb, sizeof(sctp_cwrhdr_t)); | |
2590 | ||
34bcca28 | 2591 | lowest_tsn = ntohl(cwr->lowest_tsn); |
1da177e4 LT |
2592 | |
2593 | /* Does this CWR ack the last sent congestion notification? */ | |
34bcca28 | 2594 | if (TSN_lte(asoc->last_ecne_tsn, lowest_tsn)) { |
1da177e4 LT |
2595 | /* Stop sending ECNE. */ |
2596 | sctp_add_cmd_sf(commands, | |
2597 | SCTP_CMD_ECN_CWR, | |
34bcca28 | 2598 | SCTP_U32(lowest_tsn)); |
1da177e4 LT |
2599 | } |
2600 | return SCTP_DISPOSITION_CONSUME; | |
2601 | } | |
2602 | ||
2603 | /* | |
2604 | * sctp_sf_do_ecne | |
2605 | * | |
2606 | * Section: Appendix A: Explicit Congestion Notification | |
2607 | * | |
2608 | * ECN-Echo | |
2609 | * | |
2610 | * RFC 2481 details a specific bit for a receiver to send back in its | |
2611 | * TCP acknowledgements to notify the sender of the Congestion | |
2612 | * Experienced (CE) bit having arrived from the network. For SCTP this | |
2613 | * same indication is made by including the ECNE chunk. This chunk | |
2614 | * contains one data element, i.e. the lowest TSN associated with the IP | |
2615 | * datagram marked with the CE bit..... | |
2616 | * | |
2617 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2618 | * Inputs | |
2619 | * (endpoint, asoc, chunk) | |
2620 | * | |
2621 | * Outputs | |
2622 | * (asoc, reply_msg, msg_up, timers, counters) | |
2623 | * | |
2624 | * The return value is the disposition of the chunk. | |
2625 | */ | |
2626 | sctp_disposition_t sctp_sf_do_ecne(const struct sctp_endpoint *ep, | |
2627 | const struct sctp_association *asoc, | |
2628 | const sctp_subtype_t type, | |
2629 | void *arg, | |
2630 | sctp_cmd_seq_t *commands) | |
2631 | { | |
2632 | sctp_ecnehdr_t *ecne; | |
2633 | struct sctp_chunk *chunk = arg; | |
2634 | ||
2635 | if (!sctp_vtag_verify(chunk, asoc)) | |
2636 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2637 | ||
2638 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_ecne_chunk_t))) | |
2639 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2640 | commands); | |
2641 | ||
2642 | ecne = (sctp_ecnehdr_t *) chunk->skb->data; | |
2643 | skb_pull(chunk->skb, sizeof(sctp_ecnehdr_t)); | |
2644 | ||
2645 | /* If this is a newer ECNE than the last CWR packet we sent out */ | |
2646 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_ECNE, | |
2647 | SCTP_U32(ntohl(ecne->lowest_tsn))); | |
2648 | ||
2649 | return SCTP_DISPOSITION_CONSUME; | |
2650 | } | |
2651 | ||
2652 | /* | |
2653 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
2654 | * | |
2655 | * The SCTP endpoint MUST always acknowledge the reception of each valid | |
2656 | * DATA chunk. | |
2657 | * | |
2658 | * The guidelines on delayed acknowledgement algorithm specified in | |
2659 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
2660 | * acknowledgement SHOULD be generated for at least every second packet | |
2661 | * (not every second DATA chunk) received, and SHOULD be generated within | |
2662 | * 200 ms of the arrival of any unacknowledged DATA chunk. In some | |
2663 | * situations it may be beneficial for an SCTP transmitter to be more | |
2664 | * conservative than the algorithms detailed in this document allow. | |
2665 | * However, an SCTP transmitter MUST NOT be more aggressive than the | |
2666 | * following algorithms allow. | |
2667 | * | |
2668 | * A SCTP receiver MUST NOT generate more than one SACK for every | |
2669 | * incoming packet, other than to update the offered window as the | |
2670 | * receiving application consumes new data. | |
2671 | * | |
2672 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2673 | * | |
2674 | * Inputs | |
2675 | * (endpoint, asoc, chunk) | |
2676 | * | |
2677 | * Outputs | |
2678 | * (asoc, reply_msg, msg_up, timers, counters) | |
2679 | * | |
2680 | * The return value is the disposition of the chunk. | |
2681 | */ | |
2682 | sctp_disposition_t sctp_sf_eat_data_6_2(const struct sctp_endpoint *ep, | |
2683 | const struct sctp_association *asoc, | |
2684 | const sctp_subtype_t type, | |
2685 | void *arg, | |
2686 | sctp_cmd_seq_t *commands) | |
2687 | { | |
2688 | struct sctp_chunk *chunk = arg; | |
2689 | int error; | |
2690 | ||
2691 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2692 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2693 | SCTP_NULL()); | |
2694 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 2695 | } |
1da177e4 LT |
2696 | |
2697 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
2698 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2699 | commands); | |
2700 | ||
2701 | error = sctp_eat_data(asoc, chunk, commands ); | |
2702 | switch (error) { | |
2703 | case SCTP_IERROR_NO_ERROR: | |
2704 | break; | |
2705 | case SCTP_IERROR_HIGH_TSN: | |
2706 | case SCTP_IERROR_BAD_STREAM: | |
ac0b0462 | 2707 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2708 | goto discard_noforce; |
2709 | case SCTP_IERROR_DUP_TSN: | |
2710 | case SCTP_IERROR_IGNORE_TSN: | |
ac0b0462 | 2711 | SCTP_INC_STATS(SCTP_MIB_IN_DATA_CHUNK_DISCARDS); |
1da177e4 LT |
2712 | goto discard_force; |
2713 | case SCTP_IERROR_NO_DATA: | |
2714 | goto consume; | |
2715 | default: | |
2716 | BUG(); | |
2717 | } | |
2718 | ||
2719 | if (asoc->autoclose) { | |
2720 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2721 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
2722 | } | |
2723 | ||
2724 | /* If this is the last chunk in a packet, we need to count it | |
2725 | * toward sack generation. Note that we need to SACK every | |
2726 | * OTHER packet containing data chunks, EVEN IF WE DISCARD | |
2727 | * THEM. We elect to NOT generate SACK's if the chunk fails | |
2728 | * the verification tag test. | |
2729 | * | |
2730 | * RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2731 | * | |
2732 | * The SCTP endpoint MUST always acknowledge the reception of | |
2733 | * each valid DATA chunk. | |
2734 | * | |
2735 | * The guidelines on delayed acknowledgement algorithm | |
2736 | * specified in Section 4.2 of [RFC2581] SHOULD be followed. | |
2737 | * Specifically, an acknowledgement SHOULD be generated for at | |
2738 | * least every second packet (not every second DATA chunk) | |
2739 | * received, and SHOULD be generated within 200 ms of the | |
2740 | * arrival of any unacknowledged DATA chunk. In some | |
2741 | * situations it may be beneficial for an SCTP transmitter to | |
2742 | * be more conservative than the algorithms detailed in this | |
2743 | * document allow. However, an SCTP transmitter MUST NOT be | |
2744 | * more aggressive than the following algorithms allow. | |
2745 | */ | |
52ccb8e9 | 2746 | if (chunk->end_of_packet) |
1da177e4 LT |
2747 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); |
2748 | ||
1da177e4 LT |
2749 | return SCTP_DISPOSITION_CONSUME; |
2750 | ||
2751 | discard_force: | |
2752 | /* RFC 2960 6.2 Acknowledgement on Reception of DATA Chunks | |
2753 | * | |
2754 | * When a packet arrives with duplicate DATA chunk(s) and with | |
2755 | * no new DATA chunk(s), the endpoint MUST immediately send a | |
2756 | * SACK with no delay. If a packet arrives with duplicate | |
2757 | * DATA chunk(s) bundled with new DATA chunks, the endpoint | |
2758 | * MAY immediately send a SACK. Normally receipt of duplicate | |
2759 | * DATA chunks will occur when the original SACK chunk was lost | |
2760 | * and the peer's RTO has expired. The duplicate TSN number(s) | |
2761 | * SHOULD be reported in the SACK as duplicate. | |
2762 | */ | |
2763 | /* In our case, we split the MAY SACK advice up whether or not | |
2764 | * the last chunk is a duplicate.' | |
2765 | */ | |
2766 | if (chunk->end_of_packet) | |
2767 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
2768 | return SCTP_DISPOSITION_DISCARD; | |
2769 | ||
2770 | discard_noforce: | |
52ccb8e9 | 2771 | if (chunk->end_of_packet) |
1da177e4 LT |
2772 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); |
2773 | ||
1da177e4 LT |
2774 | return SCTP_DISPOSITION_DISCARD; |
2775 | consume: | |
2776 | return SCTP_DISPOSITION_CONSUME; | |
d808ad9a | 2777 | |
1da177e4 LT |
2778 | } |
2779 | ||
2780 | /* | |
2781 | * sctp_sf_eat_data_fast_4_4 | |
2782 | * | |
2783 | * Section: 4 (4) | |
2784 | * (4) In SHUTDOWN-SENT state the endpoint MUST acknowledge any received | |
2785 | * DATA chunks without delay. | |
2786 | * | |
2787 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2788 | * Inputs | |
2789 | * (endpoint, asoc, chunk) | |
2790 | * | |
2791 | * Outputs | |
2792 | * (asoc, reply_msg, msg_up, timers, counters) | |
2793 | * | |
2794 | * The return value is the disposition of the chunk. | |
2795 | */ | |
2796 | sctp_disposition_t sctp_sf_eat_data_fast_4_4(const struct sctp_endpoint *ep, | |
2797 | const struct sctp_association *asoc, | |
2798 | const sctp_subtype_t type, | |
2799 | void *arg, | |
2800 | sctp_cmd_seq_t *commands) | |
2801 | { | |
2802 | struct sctp_chunk *chunk = arg; | |
2803 | int error; | |
2804 | ||
2805 | if (!sctp_vtag_verify(chunk, asoc)) { | |
2806 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
2807 | SCTP_NULL()); | |
2808 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2809 | } | |
2810 | ||
2811 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_data_chunk_t))) | |
2812 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2813 | commands); | |
2814 | ||
2815 | error = sctp_eat_data(asoc, chunk, commands ); | |
2816 | switch (error) { | |
2817 | case SCTP_IERROR_NO_ERROR: | |
2818 | case SCTP_IERROR_HIGH_TSN: | |
2819 | case SCTP_IERROR_DUP_TSN: | |
2820 | case SCTP_IERROR_IGNORE_TSN: | |
2821 | case SCTP_IERROR_BAD_STREAM: | |
2822 | break; | |
2823 | case SCTP_IERROR_NO_DATA: | |
2824 | goto consume; | |
2825 | default: | |
2826 | BUG(); | |
2827 | } | |
2828 | ||
2829 | /* Go a head and force a SACK, since we are shutting down. */ | |
2830 | ||
2831 | /* Implementor's Guide. | |
2832 | * | |
2833 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
2834 | * respond to each received packet containing one or more DATA chunk(s) | |
2835 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
2836 | */ | |
2837 | if (chunk->end_of_packet) { | |
2838 | /* We must delay the chunk creation since the cumulative | |
2839 | * TSN has not been updated yet. | |
2840 | */ | |
2841 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
2842 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
2843 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
2844 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
2845 | } | |
2846 | ||
2847 | consume: | |
2848 | return SCTP_DISPOSITION_CONSUME; | |
2849 | } | |
2850 | ||
2851 | /* | |
2852 | * Section: 6.2 Processing a Received SACK | |
2853 | * D) Any time a SACK arrives, the endpoint performs the following: | |
2854 | * | |
2855 | * i) If Cumulative TSN Ack is less than the Cumulative TSN Ack Point, | |
2856 | * then drop the SACK. Since Cumulative TSN Ack is monotonically | |
2857 | * increasing, a SACK whose Cumulative TSN Ack is less than the | |
2858 | * Cumulative TSN Ack Point indicates an out-of-order SACK. | |
2859 | * | |
2860 | * ii) Set rwnd equal to the newly received a_rwnd minus the number | |
2861 | * of bytes still outstanding after processing the Cumulative TSN Ack | |
2862 | * and the Gap Ack Blocks. | |
2863 | * | |
2864 | * iii) If the SACK is missing a TSN that was previously | |
2865 | * acknowledged via a Gap Ack Block (e.g., the data receiver | |
2866 | * reneged on the data), then mark the corresponding DATA chunk | |
2867 | * as available for retransmit: Mark it as missing for fast | |
2868 | * retransmit as described in Section 7.2.4 and if no retransmit | |
2869 | * timer is running for the destination address to which the DATA | |
2870 | * chunk was originally transmitted, then T3-rtx is started for | |
2871 | * that destination address. | |
2872 | * | |
2873 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
2874 | * | |
2875 | * Inputs | |
2876 | * (endpoint, asoc, chunk) | |
2877 | * | |
2878 | * Outputs | |
2879 | * (asoc, reply_msg, msg_up, timers, counters) | |
2880 | * | |
2881 | * The return value is the disposition of the chunk. | |
2882 | */ | |
2883 | sctp_disposition_t sctp_sf_eat_sack_6_2(const struct sctp_endpoint *ep, | |
2884 | const struct sctp_association *asoc, | |
2885 | const sctp_subtype_t type, | |
2886 | void *arg, | |
2887 | sctp_cmd_seq_t *commands) | |
2888 | { | |
2889 | struct sctp_chunk *chunk = arg; | |
2890 | sctp_sackhdr_t *sackh; | |
2891 | __u32 ctsn; | |
2892 | ||
2893 | if (!sctp_vtag_verify(chunk, asoc)) | |
2894 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2895 | ||
2896 | /* Make sure that the SACK chunk has a valid length. */ | |
2897 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_sack_chunk_t))) | |
2898 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
2899 | commands); | |
2900 | ||
2901 | /* Pull the SACK chunk from the data buffer */ | |
2902 | sackh = sctp_sm_pull_sack(chunk); | |
2903 | /* Was this a bogus SACK? */ | |
2904 | if (!sackh) | |
2905 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
2906 | chunk->subh.sack_hdr = sackh; | |
2907 | ctsn = ntohl(sackh->cum_tsn_ack); | |
2908 | ||
2909 | /* i) If Cumulative TSN Ack is less than the Cumulative TSN | |
2910 | * Ack Point, then drop the SACK. Since Cumulative TSN | |
2911 | * Ack is monotonically increasing, a SACK whose | |
2912 | * Cumulative TSN Ack is less than the Cumulative TSN Ack | |
2913 | * Point indicates an out-of-order SACK. | |
2914 | */ | |
2915 | if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { | |
2916 | SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); | |
2917 | SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); | |
2918 | return SCTP_DISPOSITION_DISCARD; | |
2919 | } | |
2920 | ||
aecedeab WY |
2921 | /* If Cumulative TSN Ack beyond the max tsn currently |
2922 | * send, terminating the association and respond to the | |
2923 | * sender with an ABORT. | |
2924 | */ | |
2925 | if (!TSN_lt(ctsn, asoc->next_tsn)) | |
2926 | return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); | |
2927 | ||
1da177e4 LT |
2928 | /* Return this SACK for further processing. */ |
2929 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, SCTP_SACKH(sackh)); | |
2930 | ||
2931 | /* Note: We do the rest of the work on the PROCESS_SACK | |
2932 | * sideeffect. | |
2933 | */ | |
2934 | return SCTP_DISPOSITION_CONSUME; | |
2935 | } | |
2936 | ||
2937 | /* | |
2938 | * Generate an ABORT in response to a packet. | |
2939 | * | |
047a2428 | 2940 | * Section: 8.4 Handle "Out of the blue" Packets, sctpimpguide 2.41 |
1da177e4 | 2941 | * |
047a2428 JF |
2942 | * 8) The receiver should respond to the sender of the OOTB packet with |
2943 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
2944 | * MUST fill in the Verification Tag field of the outbound packet | |
2945 | * with the value found in the Verification Tag field of the OOTB | |
2946 | * packet and set the T-bit in the Chunk Flags to indicate that the | |
2947 | * Verification Tag is reflected. After sending this ABORT, the | |
2948 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
2949 | * no further action. | |
1da177e4 LT |
2950 | * |
2951 | * Verification Tag: | |
2952 | * | |
2953 | * The return value is the disposition of the chunk. | |
2954 | */ | |
ece25dfa | 2955 | static sctp_disposition_t sctp_sf_tabort_8_4_8(const struct sctp_endpoint *ep, |
1da177e4 LT |
2956 | const struct sctp_association *asoc, |
2957 | const sctp_subtype_t type, | |
2958 | void *arg, | |
2959 | sctp_cmd_seq_t *commands) | |
2960 | { | |
2961 | struct sctp_packet *packet = NULL; | |
2962 | struct sctp_chunk *chunk = arg; | |
2963 | struct sctp_chunk *abort; | |
2964 | ||
2965 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
2966 | ||
2967 | if (packet) { | |
2968 | /* Make an ABORT. The T bit will be set if the asoc | |
2969 | * is NULL. | |
2970 | */ | |
d808ad9a | 2971 | abort = sctp_make_abort(asoc, chunk, 0); |
1da177e4 LT |
2972 | if (!abort) { |
2973 | sctp_ootb_pkt_free(packet); | |
2974 | return SCTP_DISPOSITION_NOMEM; | |
2975 | } | |
2976 | ||
047a2428 JF |
2977 | /* Reflect vtag if T-Bit is set */ |
2978 | if (sctp_test_T_bit(abort)) | |
2979 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
2980 | ||
1da177e4 LT |
2981 | /* Set the skb to the belonging sock for accounting. */ |
2982 | abort->skb->sk = ep->base.sk; | |
2983 | ||
2984 | sctp_packet_append_chunk(packet, abort); | |
2985 | ||
2986 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
2987 | SCTP_PACKET(packet)); | |
2988 | ||
2989 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
2990 | ||
d3f25968 | 2991 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); |
1da177e4 LT |
2992 | return SCTP_DISPOSITION_CONSUME; |
2993 | } | |
2994 | ||
2995 | return SCTP_DISPOSITION_NOMEM; | |
2996 | } | |
2997 | ||
2998 | /* | |
2999 | * Received an ERROR chunk from peer. Generate SCTP_REMOTE_ERROR | |
3000 | * event as ULP notification for each cause included in the chunk. | |
3001 | * | |
3002 | * API 5.3.1.3 - SCTP_REMOTE_ERROR | |
3003 | * | |
3004 | * The return value is the disposition of the chunk. | |
3005 | */ | |
3006 | sctp_disposition_t sctp_sf_operr_notify(const struct sctp_endpoint *ep, | |
3007 | const struct sctp_association *asoc, | |
3008 | const sctp_subtype_t type, | |
3009 | void *arg, | |
3010 | sctp_cmd_seq_t *commands) | |
3011 | { | |
3012 | struct sctp_chunk *chunk = arg; | |
3013 | struct sctp_ulpevent *ev; | |
3014 | ||
3015 | if (!sctp_vtag_verify(chunk, asoc)) | |
3016 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3017 | ||
3018 | /* Make sure that the ERROR chunk has a valid length. */ | |
3019 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_operr_chunk_t))) | |
3020 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3021 | commands); | |
3022 | ||
3023 | while (chunk->chunk_end > chunk->skb->data) { | |
3024 | ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0, | |
3025 | GFP_ATOMIC); | |
3026 | if (!ev) | |
3027 | goto nomem; | |
3028 | ||
3029 | if (!sctp_add_cmd(commands, SCTP_CMD_EVENT_ULP, | |
3030 | SCTP_ULPEVENT(ev))) { | |
3031 | sctp_ulpevent_free(ev); | |
3032 | goto nomem; | |
3033 | } | |
3034 | ||
3035 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_OPERR, | |
d808ad9a | 3036 | SCTP_CHUNK(chunk)); |
1da177e4 LT |
3037 | } |
3038 | return SCTP_DISPOSITION_CONSUME; | |
3039 | ||
3040 | nomem: | |
3041 | return SCTP_DISPOSITION_NOMEM; | |
3042 | } | |
3043 | ||
3044 | /* | |
3045 | * Process an inbound SHUTDOWN ACK. | |
3046 | * | |
3047 | * From Section 9.2: | |
3048 | * Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3049 | * stop the T2-shutdown timer, send a SHUTDOWN COMPLETE chunk to its | |
3050 | * peer, and remove all record of the association. | |
3051 | * | |
3052 | * The return value is the disposition. | |
3053 | */ | |
3054 | sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep, | |
3055 | const struct sctp_association *asoc, | |
3056 | const sctp_subtype_t type, | |
3057 | void *arg, | |
3058 | sctp_cmd_seq_t *commands) | |
3059 | { | |
3060 | struct sctp_chunk *chunk = arg; | |
3061 | struct sctp_chunk *reply; | |
3062 | struct sctp_ulpevent *ev; | |
3063 | ||
3064 | if (!sctp_vtag_verify(chunk, asoc)) | |
3065 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3066 | ||
3067 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3068 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3069 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3070 | commands); | |
1da177e4 LT |
3071 | /* 10.2 H) SHUTDOWN COMPLETE notification |
3072 | * | |
3073 | * When SCTP completes the shutdown procedures (section 9.2) this | |
3074 | * notification is passed to the upper layer. | |
3075 | */ | |
3076 | ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP, | |
a5a35e76 | 3077 | 0, 0, 0, NULL, GFP_ATOMIC); |
1da177e4 LT |
3078 | if (!ev) |
3079 | goto nomem; | |
3080 | ||
df7deeb5 VY |
3081 | /* ...send a SHUTDOWN COMPLETE chunk to its peer, */ |
3082 | reply = sctp_make_shutdown_complete(asoc, chunk); | |
3083 | if (!reply) | |
3084 | goto nomem_chunk; | |
3085 | ||
3086 | /* Do all the commands now (after allocation), so that we | |
3087 | * have consistent state if memory allocation failes | |
3088 | */ | |
1da177e4 LT |
3089 | sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev)); |
3090 | ||
3091 | /* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall | |
3092 | * stop the T2-shutdown timer, | |
3093 | */ | |
3094 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3095 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3096 | ||
3097 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3098 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
3099 | ||
1da177e4 LT |
3100 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, |
3101 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
3102 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
3103 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3104 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
3105 | ||
3106 | /* ...and remove all record of the association. */ | |
3107 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
3108 | return SCTP_DISPOSITION_DELETE_TCB; | |
3109 | ||
df7deeb5 VY |
3110 | nomem_chunk: |
3111 | sctp_ulpevent_free(ev); | |
1da177e4 LT |
3112 | nomem: |
3113 | return SCTP_DISPOSITION_NOMEM; | |
3114 | } | |
3115 | ||
3116 | /* | |
047a2428 JF |
3117 | * RFC 2960, 8.4 - Handle "Out of the blue" Packets, sctpimpguide 2.41. |
3118 | * | |
1da177e4 LT |
3119 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
3120 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. | |
3121 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3122 | * packet must fill in the Verification Tag field of the outbound | |
3123 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
047a2428 JF |
3124 | * set the T-bit in the Chunk Flags to indicate that the Verification |
3125 | * Tag is reflected. | |
1da177e4 LT |
3126 | * |
3127 | * 8) The receiver should respond to the sender of the OOTB packet with | |
3128 | * an ABORT. When sending the ABORT, the receiver of the OOTB packet | |
3129 | * MUST fill in the Verification Tag field of the outbound packet | |
3130 | * with the value found in the Verification Tag field of the OOTB | |
047a2428 JF |
3131 | * packet and set the T-bit in the Chunk Flags to indicate that the |
3132 | * Verification Tag is reflected. After sending this ABORT, the | |
3133 | * receiver of the OOTB packet shall discard the OOTB packet and take | |
3134 | * no further action. | |
1da177e4 LT |
3135 | */ |
3136 | sctp_disposition_t sctp_sf_ootb(const struct sctp_endpoint *ep, | |
3137 | const struct sctp_association *asoc, | |
3138 | const sctp_subtype_t type, | |
3139 | void *arg, | |
3140 | sctp_cmd_seq_t *commands) | |
3141 | { | |
3142 | struct sctp_chunk *chunk = arg; | |
3143 | struct sk_buff *skb = chunk->skb; | |
3144 | sctp_chunkhdr_t *ch; | |
3145 | __u8 *ch_end; | |
3146 | int ootb_shut_ack = 0; | |
3147 | ||
3148 | SCTP_INC_STATS(SCTP_MIB_OUTOFBLUES); | |
3149 | ||
3150 | ch = (sctp_chunkhdr_t *) chunk->chunk_hdr; | |
3151 | do { | |
ece25dfa | 3152 | /* Report violation if the chunk is less then minimal */ |
1da177e4 | 3153 | if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) |
ece25dfa VY |
3154 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, |
3155 | commands); | |
1da177e4 | 3156 | |
ece25dfa VY |
3157 | /* Now that we know we at least have a chunk header, |
3158 | * do things that are type appropriate. | |
3159 | */ | |
1da177e4 LT |
3160 | if (SCTP_CID_SHUTDOWN_ACK == ch->type) |
3161 | ootb_shut_ack = 1; | |
3162 | ||
3163 | /* RFC 2960, Section 3.3.7 | |
3164 | * Moreover, under any circumstances, an endpoint that | |
3165 | * receives an ABORT MUST NOT respond to that ABORT by | |
3166 | * sending an ABORT of its own. | |
3167 | */ | |
3168 | if (SCTP_CID_ABORT == ch->type) | |
3169 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
d808ad9a | 3170 | |
ece25dfa VY |
3171 | /* Report violation if chunk len overflows */ |
3172 | ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); | |
3173 | if (ch_end > skb_tail_pointer(skb)) | |
3174 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3175 | commands); | |
3176 | ||
1da177e4 | 3177 | ch = (sctp_chunkhdr_t *) ch_end; |
27a884dc | 3178 | } while (ch_end < skb_tail_pointer(skb)); |
1da177e4 LT |
3179 | |
3180 | if (ootb_shut_ack) | |
d3f25968 | 3181 | return sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands); |
1da177e4 | 3182 | else |
d3f25968 | 3183 | return sctp_sf_tabort_8_4_8(ep, asoc, type, arg, commands); |
1da177e4 LT |
3184 | } |
3185 | ||
3186 | /* | |
3187 | * Handle an "Out of the blue" SHUTDOWN ACK. | |
3188 | * | |
047a2428 JF |
3189 | * Section: 8.4 5, sctpimpguide 2.41. |
3190 | * | |
1da177e4 | 3191 | * 5) If the packet contains a SHUTDOWN ACK chunk, the receiver should |
047a2428 JF |
3192 | * respond to the sender of the OOTB packet with a SHUTDOWN COMPLETE. |
3193 | * When sending the SHUTDOWN COMPLETE, the receiver of the OOTB | |
3194 | * packet must fill in the Verification Tag field of the outbound | |
3195 | * packet with the Verification Tag received in the SHUTDOWN ACK and | |
3196 | * set the T-bit in the Chunk Flags to indicate that the Verification | |
3197 | * Tag is reflected. | |
1da177e4 LT |
3198 | * |
3199 | * Inputs | |
3200 | * (endpoint, asoc, type, arg, commands) | |
3201 | * | |
3202 | * Outputs | |
3203 | * (sctp_disposition_t) | |
3204 | * | |
3205 | * The return value is the disposition of the chunk. | |
3206 | */ | |
3207 | static sctp_disposition_t sctp_sf_shut_8_4_5(const struct sctp_endpoint *ep, | |
3208 | const struct sctp_association *asoc, | |
3209 | const sctp_subtype_t type, | |
3210 | void *arg, | |
3211 | sctp_cmd_seq_t *commands) | |
3212 | { | |
3213 | struct sctp_packet *packet = NULL; | |
3214 | struct sctp_chunk *chunk = arg; | |
3215 | struct sctp_chunk *shut; | |
3216 | ||
3217 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
3218 | ||
3219 | if (packet) { | |
3220 | /* Make an SHUTDOWN_COMPLETE. | |
d808ad9a YH |
3221 | * The T bit will be set if the asoc is NULL. |
3222 | */ | |
1da177e4 LT |
3223 | shut = sctp_make_shutdown_complete(asoc, chunk); |
3224 | if (!shut) { | |
3225 | sctp_ootb_pkt_free(packet); | |
3226 | return SCTP_DISPOSITION_NOMEM; | |
3227 | } | |
3228 | ||
047a2428 JF |
3229 | /* Reflect vtag if T-Bit is set */ |
3230 | if (sctp_test_T_bit(shut)) | |
3231 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3232 | ||
1da177e4 LT |
3233 | /* Set the skb to the belonging sock for accounting. */ |
3234 | shut->skb->sk = ep->base.sk; | |
3235 | ||
3236 | sctp_packet_append_chunk(packet, shut); | |
3237 | ||
3238 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3239 | SCTP_PACKET(packet)); | |
3240 | ||
3241 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
3242 | ||
3243 | /* If the chunk length is invalid, we don't want to process | |
3244 | * the reset of the packet. | |
3245 | */ | |
3246 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3247 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3248 | ||
d3f25968 VY |
3249 | /* We need to discard the rest of the packet to prevent |
3250 | * potential bomming attacks from additional bundled chunks. | |
3251 | * This is documented in SCTP Threats ID. | |
3252 | */ | |
3253 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
1da177e4 LT |
3254 | } |
3255 | ||
3256 | return SCTP_DISPOSITION_NOMEM; | |
3257 | } | |
3258 | ||
3259 | /* | |
3260 | * Handle SHUTDOWN ACK in COOKIE_ECHOED or COOKIE_WAIT state. | |
3261 | * | |
3262 | * Verification Tag: 8.5.1 E) Rules for packet carrying a SHUTDOWN ACK | |
3263 | * If the receiver is in COOKIE-ECHOED or COOKIE-WAIT state the | |
3264 | * procedures in section 8.4 SHOULD be followed, in other words it | |
3265 | * should be treated as an Out Of The Blue packet. | |
3266 | * [This means that we do NOT check the Verification Tag on these | |
3267 | * chunks. --piggy ] | |
3268 | * | |
3269 | */ | |
3270 | sctp_disposition_t sctp_sf_do_8_5_1_E_sa(const struct sctp_endpoint *ep, | |
3271 | const struct sctp_association *asoc, | |
3272 | const sctp_subtype_t type, | |
3273 | void *arg, | |
3274 | sctp_cmd_seq_t *commands) | |
3275 | { | |
ece25dfa VY |
3276 | struct sctp_chunk *chunk = arg; |
3277 | ||
3278 | /* Make sure that the SHUTDOWN_ACK chunk has a valid length. */ | |
3279 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3280 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3281 | commands); | |
3282 | ||
1da177e4 LT |
3283 | /* Although we do have an association in this case, it corresponds |
3284 | * to a restarted association. So the packet is treated as an OOTB | |
3285 | * packet and the state function that handles OOTB SHUTDOWN_ACK is | |
3286 | * called with a NULL association. | |
3287 | */ | |
3288 | return sctp_sf_shut_8_4_5(ep, NULL, type, arg, commands); | |
3289 | } | |
3290 | ||
3291 | /* ADDIP Section 4.2 Upon reception of an ASCONF Chunk. */ | |
3292 | sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep, | |
3293 | const struct sctp_association *asoc, | |
3294 | const sctp_subtype_t type, void *arg, | |
3295 | sctp_cmd_seq_t *commands) | |
3296 | { | |
3297 | struct sctp_chunk *chunk = arg; | |
3298 | struct sctp_chunk *asconf_ack = NULL; | |
3299 | sctp_addiphdr_t *hdr; | |
3300 | __u32 serial; | |
3301 | ||
3302 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3303 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3304 | SCTP_NULL()); | |
3305 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3306 | } | |
3307 | ||
3308 | /* Make sure that the ASCONF ADDIP chunk has a valid length. */ | |
3309 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_addip_chunk_t))) | |
3310 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3311 | commands); | |
3312 | ||
3313 | hdr = (sctp_addiphdr_t *)chunk->skb->data; | |
3314 | serial = ntohl(hdr->serial); | |
3315 | ||
3316 | /* ADDIP 4.2 C1) Compare the value of the serial number to the value | |
3317 | * the endpoint stored in a new association variable | |
d808ad9a | 3318 | * 'Peer-Serial-Number'. |
1da177e4 LT |
3319 | */ |
3320 | if (serial == asoc->peer.addip_serial + 1) { | |
d808ad9a | 3321 | /* ADDIP 4.2 C2) If the value found in the serial number is |
1da177e4 LT |
3322 | * equal to the ('Peer-Serial-Number' + 1), the endpoint MUST |
3323 | * do V1-V5. | |
3324 | */ | |
3325 | asconf_ack = sctp_process_asconf((struct sctp_association *) | |
3326 | asoc, chunk); | |
3327 | if (!asconf_ack) | |
3328 | return SCTP_DISPOSITION_NOMEM; | |
3329 | } else if (serial == asoc->peer.addip_serial) { | |
3330 | /* ADDIP 4.2 C3) If the value found in the serial number is | |
3331 | * equal to the value stored in the 'Peer-Serial-Number' | |
3332 | * IMPLEMENTATION NOTE: As an optimization a receiver may wish | |
3333 | * to save the last ASCONF-ACK for some predetermined period of | |
3334 | * time and instead of re-processing the ASCONF (with the same | |
3335 | * serial number) it may just re-transmit the ASCONF-ACK. | |
3336 | */ | |
3337 | if (asoc->addip_last_asconf_ack) | |
3338 | asconf_ack = asoc->addip_last_asconf_ack; | |
3339 | else | |
3340 | return SCTP_DISPOSITION_DISCARD; | |
3341 | } else { | |
d808ad9a | 3342 | /* ADDIP 4.2 C4) Otherwise, the ASCONF Chunk is discarded since |
1da177e4 | 3343 | * it must be either a stale packet or from an attacker. |
d808ad9a | 3344 | */ |
1da177e4 LT |
3345 | return SCTP_DISPOSITION_DISCARD; |
3346 | } | |
3347 | ||
3348 | /* ADDIP 4.2 C5) In both cases C2 and C3 the ASCONF-ACK MUST be sent | |
3349 | * back to the source address contained in the IP header of the ASCONF | |
3350 | * being responded to. | |
3351 | */ | |
3352 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(asconf_ack)); | |
d808ad9a | 3353 | |
1da177e4 LT |
3354 | return SCTP_DISPOSITION_CONSUME; |
3355 | } | |
3356 | ||
3357 | /* | |
3358 | * ADDIP Section 4.3 General rules for address manipulation | |
3359 | * When building TLV parameters for the ASCONF Chunk that will add or | |
3360 | * delete IP addresses the D0 to D13 rules should be applied: | |
3361 | */ | |
3362 | sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, | |
3363 | const struct sctp_association *asoc, | |
d808ad9a | 3364 | const sctp_subtype_t type, void *arg, |
1da177e4 LT |
3365 | sctp_cmd_seq_t *commands) |
3366 | { | |
3367 | struct sctp_chunk *asconf_ack = arg; | |
3368 | struct sctp_chunk *last_asconf = asoc->addip_last_asconf; | |
3369 | struct sctp_chunk *abort; | |
3370 | sctp_addiphdr_t *addip_hdr; | |
3371 | __u32 sent_serial, rcvd_serial; | |
3372 | ||
3373 | if (!sctp_vtag_verify(asconf_ack, asoc)) { | |
3374 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3375 | SCTP_NULL()); | |
3376 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3377 | } | |
3378 | ||
3379 | /* Make sure that the ADDIP chunk has a valid length. */ | |
3380 | if (!sctp_chunk_length_valid(asconf_ack, sizeof(sctp_addip_chunk_t))) | |
3381 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3382 | commands); | |
3383 | ||
3384 | addip_hdr = (sctp_addiphdr_t *)asconf_ack->skb->data; | |
3385 | rcvd_serial = ntohl(addip_hdr->serial); | |
3386 | ||
3387 | if (last_asconf) { | |
3388 | addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr; | |
3389 | sent_serial = ntohl(addip_hdr->serial); | |
3390 | } else { | |
3391 | sent_serial = asoc->addip_serial - 1; | |
3392 | } | |
3393 | ||
3394 | /* D0) If an endpoint receives an ASCONF-ACK that is greater than or | |
3395 | * equal to the next serial number to be used but no ASCONF chunk is | |
3396 | * outstanding the endpoint MUST ABORT the association. Note that a | |
3397 | * sequence number is greater than if it is no more than 2^^31-1 | |
3398 | * larger than the current sequence number (using serial arithmetic). | |
3399 | */ | |
3400 | if (ADDIP_SERIAL_gte(rcvd_serial, sent_serial + 1) && | |
3401 | !(asoc->addip_last_asconf)) { | |
3402 | abort = sctp_make_abort(asoc, asconf_ack, | |
3403 | sizeof(sctp_errhdr_t)); | |
3404 | if (abort) { | |
00f1c2df | 3405 | sctp_init_cause(abort, SCTP_ERROR_ASCONF_ACK, 0); |
1da177e4 LT |
3406 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3407 | SCTP_CHUNK(abort)); | |
3408 | } | |
3409 | /* We are going to ABORT, so we might as well stop | |
3410 | * processing the rest of the chunks in the packet. | |
3411 | */ | |
3412 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3413 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3414 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3415 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3416 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3417 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3418 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3419 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3420 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3421 | return SCTP_DISPOSITION_ABORT; | |
3422 | } | |
3423 | ||
3424 | if ((rcvd_serial == sent_serial) && asoc->addip_last_asconf) { | |
3425 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3426 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
3427 | ||
3428 | if (!sctp_process_asconf_ack((struct sctp_association *)asoc, | |
3429 | asconf_ack)) | |
3430 | return SCTP_DISPOSITION_CONSUME; | |
3431 | ||
3432 | abort = sctp_make_abort(asoc, asconf_ack, | |
3433 | sizeof(sctp_errhdr_t)); | |
3434 | if (abort) { | |
00f1c2df | 3435 | sctp_init_cause(abort, SCTP_ERROR_RSRC_LOW, 0); |
1da177e4 LT |
3436 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, |
3437 | SCTP_CHUNK(abort)); | |
3438 | } | |
3439 | /* We are going to ABORT, so we might as well stop | |
3440 | * processing the rest of the chunks in the packet. | |
3441 | */ | |
3442 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 | 3443 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
d808ad9a | 3444 | SCTP_ERROR(ECONNABORTED)); |
1da177e4 | 3445 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 3446 | SCTP_PERR(SCTP_ERROR_ASCONF_ACK)); |
1da177e4 LT |
3447 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
3448 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3449 | return SCTP_DISPOSITION_ABORT; | |
3450 | } | |
3451 | ||
3452 | return SCTP_DISPOSITION_DISCARD; | |
3453 | } | |
3454 | ||
3455 | /* | |
3456 | * PR-SCTP Section 3.6 Receiver Side Implementation of PR-SCTP | |
3457 | * | |
3458 | * When a FORWARD TSN chunk arrives, the data receiver MUST first update | |
3459 | * its cumulative TSN point to the value carried in the FORWARD TSN | |
3460 | * chunk, and then MUST further advance its cumulative TSN point locally | |
3461 | * if possible. | |
3462 | * After the above processing, the data receiver MUST stop reporting any | |
3463 | * missing TSNs earlier than or equal to the new cumulative TSN point. | |
3464 | * | |
3465 | * Verification Tag: 8.5 Verification Tag [Normal verification] | |
3466 | * | |
3467 | * The return value is the disposition of the chunk. | |
3468 | */ | |
3469 | sctp_disposition_t sctp_sf_eat_fwd_tsn(const struct sctp_endpoint *ep, | |
3470 | const struct sctp_association *asoc, | |
3471 | const sctp_subtype_t type, | |
3472 | void *arg, | |
3473 | sctp_cmd_seq_t *commands) | |
3474 | { | |
3475 | struct sctp_chunk *chunk = arg; | |
3476 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
3477 | __u16 len; | |
3478 | __u32 tsn; | |
3479 | ||
3480 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3481 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3482 | SCTP_NULL()); | |
3483 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3484 | } | |
3485 | ||
3486 | /* Make sure that the FORWARD_TSN chunk has valid length. */ | |
3487 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3488 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3489 | commands); | |
3490 | ||
3491 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3492 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3493 | len = ntohs(chunk->chunk_hdr->length); | |
3494 | len -= sizeof(struct sctp_chunkhdr); | |
3495 | skb_pull(chunk->skb, len); | |
3496 | ||
3497 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
3498 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __FUNCTION__, tsn); | |
3499 | ||
3500 | /* The TSN is too high--silently discard the chunk and count on it | |
3501 | * getting retransmitted later. | |
3502 | */ | |
3503 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3504 | goto discard_noforce; | |
3505 | ||
3506 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); | |
3507 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3508 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3509 | SCTP_CHUNK(chunk)); |
d808ad9a | 3510 | |
1da177e4 LT |
3511 | /* Count this as receiving DATA. */ |
3512 | if (asoc->autoclose) { | |
3513 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3514 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
3515 | } | |
d808ad9a | 3516 | |
1da177e4 | 3517 | /* FIXME: For now send a SACK, but DATA processing may |
d808ad9a | 3518 | * send another. |
1da177e4 LT |
3519 | */ |
3520 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_NOFORCE()); | |
1da177e4 LT |
3521 | |
3522 | return SCTP_DISPOSITION_CONSUME; | |
3523 | ||
3524 | discard_noforce: | |
3525 | return SCTP_DISPOSITION_DISCARD; | |
3526 | } | |
3527 | ||
3528 | sctp_disposition_t sctp_sf_eat_fwd_tsn_fast( | |
3529 | const struct sctp_endpoint *ep, | |
3530 | const struct sctp_association *asoc, | |
3531 | const sctp_subtype_t type, | |
3532 | void *arg, | |
3533 | sctp_cmd_seq_t *commands) | |
3534 | { | |
3535 | struct sctp_chunk *chunk = arg; | |
3536 | struct sctp_fwdtsn_hdr *fwdtsn_hdr; | |
3537 | __u16 len; | |
3538 | __u32 tsn; | |
3539 | ||
3540 | if (!sctp_vtag_verify(chunk, asoc)) { | |
3541 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_BAD_TAG, | |
3542 | SCTP_NULL()); | |
3543 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3544 | } | |
3545 | ||
3546 | /* Make sure that the FORWARD_TSN chunk has a valid length. */ | |
3547 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_fwdtsn_chunk))) | |
3548 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3549 | commands); | |
3550 | ||
3551 | fwdtsn_hdr = (struct sctp_fwdtsn_hdr *)chunk->skb->data; | |
3552 | chunk->subh.fwdtsn_hdr = fwdtsn_hdr; | |
3553 | len = ntohs(chunk->chunk_hdr->length); | |
3554 | len -= sizeof(struct sctp_chunkhdr); | |
3555 | skb_pull(chunk->skb, len); | |
3556 | ||
3557 | tsn = ntohl(fwdtsn_hdr->new_cum_tsn); | |
3558 | SCTP_DEBUG_PRINTK("%s: TSN 0x%x.\n", __FUNCTION__, tsn); | |
3559 | ||
3560 | /* The TSN is too high--silently discard the chunk and count on it | |
3561 | * getting retransmitted later. | |
3562 | */ | |
3563 | if (sctp_tsnmap_check(&asoc->peer.tsn_map, tsn) < 0) | |
3564 | goto gen_shutdown; | |
3565 | ||
3566 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_FWDTSN, SCTP_U32(tsn)); | |
3567 | if (len > sizeof(struct sctp_fwdtsn_hdr)) | |
d808ad9a | 3568 | sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_FWDTSN, |
1da177e4 | 3569 | SCTP_CHUNK(chunk)); |
d808ad9a | 3570 | |
1da177e4 LT |
3571 | /* Go a head and force a SACK, since we are shutting down. */ |
3572 | gen_shutdown: | |
3573 | /* Implementor's Guide. | |
3574 | * | |
3575 | * While in SHUTDOWN-SENT state, the SHUTDOWN sender MUST immediately | |
3576 | * respond to each received packet containing one or more DATA chunk(s) | |
3577 | * with a SACK, a SHUTDOWN chunk, and restart the T2-shutdown timer | |
3578 | */ | |
3579 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SHUTDOWN, SCTP_NULL()); | |
3580 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); | |
3581 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
3582 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
3583 | ||
d808ad9a | 3584 | return SCTP_DISPOSITION_CONSUME; |
1da177e4 LT |
3585 | } |
3586 | ||
3587 | /* | |
3588 | * Process an unknown chunk. | |
3589 | * | |
3590 | * Section: 3.2. Also, 2.1 in the implementor's guide. | |
3591 | * | |
3592 | * Chunk Types are encoded such that the highest-order two bits specify | |
3593 | * the action that must be taken if the processing endpoint does not | |
3594 | * recognize the Chunk Type. | |
3595 | * | |
3596 | * 00 - Stop processing this SCTP packet and discard it, do not process | |
3597 | * any further chunks within it. | |
3598 | * | |
3599 | * 01 - Stop processing this SCTP packet and discard it, do not process | |
3600 | * any further chunks within it, and report the unrecognized | |
3601 | * chunk in an 'Unrecognized Chunk Type'. | |
3602 | * | |
3603 | * 10 - Skip this chunk and continue processing. | |
3604 | * | |
3605 | * 11 - Skip this chunk and continue processing, but report in an ERROR | |
3606 | * Chunk using the 'Unrecognized Chunk Type' cause of error. | |
3607 | * | |
3608 | * The return value is the disposition of the chunk. | |
3609 | */ | |
3610 | sctp_disposition_t sctp_sf_unk_chunk(const struct sctp_endpoint *ep, | |
3611 | const struct sctp_association *asoc, | |
3612 | const sctp_subtype_t type, | |
3613 | void *arg, | |
3614 | sctp_cmd_seq_t *commands) | |
3615 | { | |
3616 | struct sctp_chunk *unk_chunk = arg; | |
3617 | struct sctp_chunk *err_chunk; | |
3618 | sctp_chunkhdr_t *hdr; | |
3619 | ||
3620 | SCTP_DEBUG_PRINTK("Processing the unknown chunk id %d.\n", type.chunk); | |
3621 | ||
3622 | if (!sctp_vtag_verify(unk_chunk, asoc)) | |
3623 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3624 | ||
3625 | /* Make sure that the chunk has a valid length. | |
3626 | * Since we don't know the chunk type, we use a general | |
3627 | * chunkhdr structure to make a comparison. | |
3628 | */ | |
3629 | if (!sctp_chunk_length_valid(unk_chunk, sizeof(sctp_chunkhdr_t))) | |
3630 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3631 | commands); | |
3632 | ||
3633 | switch (type.chunk & SCTP_CID_ACTION_MASK) { | |
3634 | case SCTP_CID_ACTION_DISCARD: | |
3635 | /* Discard the packet. */ | |
3636 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3637 | break; | |
3638 | case SCTP_CID_ACTION_DISCARD_ERR: | |
3639 | /* Discard the packet. */ | |
3640 | sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
3641 | ||
3642 | /* Generate an ERROR chunk as response. */ | |
3643 | hdr = unk_chunk->chunk_hdr; | |
3644 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
3645 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
3646 | WORD_ROUND(ntohs(hdr->length))); | |
3647 | if (err_chunk) { | |
3648 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3649 | SCTP_CHUNK(err_chunk)); | |
3650 | } | |
3651 | return SCTP_DISPOSITION_CONSUME; | |
3652 | break; | |
3653 | case SCTP_CID_ACTION_SKIP: | |
3654 | /* Skip the chunk. */ | |
3655 | return SCTP_DISPOSITION_DISCARD; | |
3656 | break; | |
3657 | case SCTP_CID_ACTION_SKIP_ERR: | |
3658 | /* Generate an ERROR chunk as response. */ | |
3659 | hdr = unk_chunk->chunk_hdr; | |
3660 | err_chunk = sctp_make_op_error(asoc, unk_chunk, | |
3661 | SCTP_ERROR_UNKNOWN_CHUNK, hdr, | |
3662 | WORD_ROUND(ntohs(hdr->length))); | |
3663 | if (err_chunk) { | |
3664 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
3665 | SCTP_CHUNK(err_chunk)); | |
3666 | } | |
3667 | /* Skip the chunk. */ | |
3668 | return SCTP_DISPOSITION_CONSUME; | |
3669 | break; | |
3670 | default: | |
3671 | break; | |
3672 | } | |
3673 | ||
3674 | return SCTP_DISPOSITION_DISCARD; | |
3675 | } | |
3676 | ||
3677 | /* | |
3678 | * Discard the chunk. | |
3679 | * | |
3680 | * Section: 0.2, 5.2.3, 5.2.5, 5.2.6, 6.0, 8.4.6, 8.5.1c, 9.2 | |
3681 | * [Too numerous to mention...] | |
3682 | * Verification Tag: No verification needed. | |
3683 | * Inputs | |
3684 | * (endpoint, asoc, chunk) | |
3685 | * | |
3686 | * Outputs | |
3687 | * (asoc, reply_msg, msg_up, timers, counters) | |
3688 | * | |
3689 | * The return value is the disposition of the chunk. | |
3690 | */ | |
3691 | sctp_disposition_t sctp_sf_discard_chunk(const struct sctp_endpoint *ep, | |
3692 | const struct sctp_association *asoc, | |
3693 | const sctp_subtype_t type, | |
3694 | void *arg, | |
3695 | sctp_cmd_seq_t *commands) | |
3696 | { | |
ece25dfa VY |
3697 | struct sctp_chunk *chunk = arg; |
3698 | ||
3699 | /* Make sure that the chunk has a valid length. | |
3700 | * Since we don't know the chunk type, we use a general | |
3701 | * chunkhdr structure to make a comparison. | |
3702 | */ | |
3703 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3704 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3705 | commands); | |
3706 | ||
1da177e4 LT |
3707 | SCTP_DEBUG_PRINTK("Chunk %d is discarded\n", type.chunk); |
3708 | return SCTP_DISPOSITION_DISCARD; | |
3709 | } | |
3710 | ||
3711 | /* | |
3712 | * Discard the whole packet. | |
3713 | * | |
3714 | * Section: 8.4 2) | |
3715 | * | |
3716 | * 2) If the OOTB packet contains an ABORT chunk, the receiver MUST | |
3717 | * silently discard the OOTB packet and take no further action. | |
1da177e4 LT |
3718 | * |
3719 | * Verification Tag: No verification necessary | |
3720 | * | |
3721 | * Inputs | |
3722 | * (endpoint, asoc, chunk) | |
3723 | * | |
3724 | * Outputs | |
3725 | * (asoc, reply_msg, msg_up, timers, counters) | |
3726 | * | |
3727 | * The return value is the disposition of the chunk. | |
3728 | */ | |
3729 | sctp_disposition_t sctp_sf_pdiscard(const struct sctp_endpoint *ep, | |
3730 | const struct sctp_association *asoc, | |
3731 | const sctp_subtype_t type, | |
3732 | void *arg, | |
3733 | sctp_cmd_seq_t *commands) | |
3734 | { | |
ac0b0462 | 3735 | SCTP_INC_STATS(SCTP_MIB_IN_PKT_DISCARDS); |
1da177e4 LT |
3736 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET, SCTP_NULL()); |
3737 | ||
3738 | return SCTP_DISPOSITION_CONSUME; | |
3739 | } | |
3740 | ||
3741 | ||
3742 | /* | |
3743 | * The other end is violating protocol. | |
3744 | * | |
3745 | * Section: Not specified | |
3746 | * Verification Tag: Not specified | |
3747 | * Inputs | |
3748 | * (endpoint, asoc, chunk) | |
3749 | * | |
3750 | * Outputs | |
3751 | * (asoc, reply_msg, msg_up, timers, counters) | |
3752 | * | |
3753 | * We simply tag the chunk as a violation. The state machine will log | |
3754 | * the violation and continue. | |
3755 | */ | |
3756 | sctp_disposition_t sctp_sf_violation(const struct sctp_endpoint *ep, | |
3757 | const struct sctp_association *asoc, | |
3758 | const sctp_subtype_t type, | |
3759 | void *arg, | |
3760 | sctp_cmd_seq_t *commands) | |
3761 | { | |
ece25dfa VY |
3762 | struct sctp_chunk *chunk = arg; |
3763 | ||
3764 | /* Make sure that the chunk has a valid length. */ | |
3765 | if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t))) | |
3766 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
3767 | commands); | |
3768 | ||
1da177e4 LT |
3769 | return SCTP_DISPOSITION_VIOLATION; |
3770 | } | |
3771 | ||
1da177e4 | 3772 | /* |
aecedeab | 3773 | * Common function to handle a protocol violation. |
1da177e4 | 3774 | */ |
aecedeab | 3775 | static sctp_disposition_t sctp_sf_abort_violation( |
ece25dfa | 3776 | const struct sctp_endpoint *ep, |
1da177e4 | 3777 | const struct sctp_association *asoc, |
1da177e4 | 3778 | void *arg, |
aecedeab WY |
3779 | sctp_cmd_seq_t *commands, |
3780 | const __u8 *payload, | |
3781 | const size_t paylen) | |
1da177e4 | 3782 | { |
ece25dfa | 3783 | struct sctp_packet *packet = NULL; |
1da177e4 LT |
3784 | struct sctp_chunk *chunk = arg; |
3785 | struct sctp_chunk *abort = NULL; | |
1da177e4 LT |
3786 | |
3787 | /* Make the abort chunk. */ | |
aecedeab | 3788 | abort = sctp_make_abort_violation(asoc, chunk, payload, paylen); |
1da177e4 LT |
3789 | if (!abort) |
3790 | goto nomem; | |
3791 | ||
ece25dfa VY |
3792 | if (asoc) { |
3793 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); | |
3794 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 | 3795 | |
ece25dfa VY |
3796 | if (asoc->state <= SCTP_STATE_COOKIE_ECHOED) { |
3797 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
3798 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
3799 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
3800 | SCTP_ERROR(ECONNREFUSED)); | |
3801 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
3802 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
3803 | } else { | |
3804 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, | |
3805 | SCTP_ERROR(ECONNABORTED)); | |
3806 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
3807 | SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); | |
3808 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
3809 | } | |
1da177e4 | 3810 | } else { |
ece25dfa VY |
3811 | packet = sctp_ootb_pkt_new(asoc, chunk); |
3812 | ||
3813 | if (!packet) | |
3814 | goto nomem_pkt; | |
3815 | ||
3816 | if (sctp_test_T_bit(abort)) | |
3817 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
3818 | ||
3819 | abort->skb->sk = ep->base.sk; | |
3820 | ||
3821 | sctp_packet_append_chunk(packet, abort); | |
3822 | ||
3823 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
3824 | SCTP_PACKET(packet)); | |
3825 | ||
3826 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
1da177e4 LT |
3827 | } |
3828 | ||
ece25dfa | 3829 | sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); |
1da177e4 LT |
3830 | |
3831 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
d808ad9a | 3832 | |
1da177e4 LT |
3833 | return SCTP_DISPOSITION_ABORT; |
3834 | ||
ece25dfa VY |
3835 | nomem_pkt: |
3836 | sctp_chunk_free(abort); | |
1da177e4 LT |
3837 | nomem: |
3838 | return SCTP_DISPOSITION_NOMEM; | |
3839 | } | |
3840 | ||
aecedeab WY |
3841 | /* |
3842 | * Handle a protocol violation when the chunk length is invalid. | |
3843 | * "Invalid" length is identified as smaller then the minimal length a | |
3844 | * given chunk can be. For example, a SACK chunk has invalid length | |
3845 | * if it's length is set to be smaller then the size of sctp_sack_chunk_t. | |
3846 | * | |
3847 | * We inform the other end by sending an ABORT with a Protocol Violation | |
3848 | * error code. | |
3849 | * | |
3850 | * Section: Not specified | |
3851 | * Verification Tag: Nothing to do | |
3852 | * Inputs | |
3853 | * (endpoint, asoc, chunk) | |
3854 | * | |
3855 | * Outputs | |
3856 | * (reply_msg, msg_up, counters) | |
3857 | * | |
3858 | * Generate an ABORT chunk and terminate the association. | |
3859 | */ | |
3860 | static sctp_disposition_t sctp_sf_violation_chunklen( | |
3861 | const struct sctp_endpoint *ep, | |
3862 | const struct sctp_association *asoc, | |
3863 | const sctp_subtype_t type, | |
3864 | void *arg, | |
3865 | sctp_cmd_seq_t *commands) | |
3866 | { | |
3867 | char err_str[]="The following chunk had invalid length:"; | |
3868 | ||
ece25dfa | 3869 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
3870 | sizeof(err_str)); |
3871 | } | |
3872 | ||
3873 | /* Handle a protocol violation when the peer trying to advance the | |
3874 | * cumulative tsn ack to a point beyond the max tsn currently sent. | |
3875 | * | |
3876 | * We inform the other end by sending an ABORT with a Protocol Violation | |
3877 | * error code. | |
3878 | */ | |
3879 | static sctp_disposition_t sctp_sf_violation_ctsn( | |
3880 | const struct sctp_endpoint *ep, | |
3881 | const struct sctp_association *asoc, | |
3882 | const sctp_subtype_t type, | |
3883 | void *arg, | |
3884 | sctp_cmd_seq_t *commands) | |
3885 | { | |
3886 | char err_str[]="The cumulative tsn ack beyond the max tsn currently sent:"; | |
3887 | ||
ece25dfa | 3888 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, |
aecedeab WY |
3889 | sizeof(err_str)); |
3890 | } | |
3891 | ||
ece25dfa VY |
3892 | /* Handle protocol violation of an invalid chunk bundling. For example, |
3893 | * when we have an association and we recieve bundled INIT-ACK, or | |
3894 | * SHUDOWN-COMPLETE, our peer is clearly violationg the "MUST NOT bundle" | |
3895 | * statement from the specs. Additinally, there might be an attacker | |
3896 | * on the path and we may not want to continue this communication. | |
3897 | */ | |
3898 | static sctp_disposition_t sctp_sf_violation_chunk( | |
3899 | const struct sctp_endpoint *ep, | |
3900 | const struct sctp_association *asoc, | |
3901 | const sctp_subtype_t type, | |
3902 | void *arg, | |
3903 | sctp_cmd_seq_t *commands) | |
3904 | { | |
3905 | char err_str[]="The following chunk violates protocol:"; | |
3906 | ||
3907 | if (!asoc) | |
3908 | return sctp_sf_violation(ep, asoc, type, arg, commands); | |
3909 | ||
3910 | return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, | |
3911 | sizeof(err_str)); | |
3912 | } | |
1da177e4 LT |
3913 | /*************************************************************************** |
3914 | * These are the state functions for handling primitive (Section 10) events. | |
3915 | ***************************************************************************/ | |
3916 | /* | |
3917 | * sctp_sf_do_prm_asoc | |
3918 | * | |
3919 | * Section: 10.1 ULP-to-SCTP | |
3920 | * B) Associate | |
3921 | * | |
3922 | * Format: ASSOCIATE(local SCTP instance name, destination transport addr, | |
3923 | * outbound stream count) | |
3924 | * -> association id [,destination transport addr list] [,outbound stream | |
3925 | * count] | |
3926 | * | |
3927 | * This primitive allows the upper layer to initiate an association to a | |
3928 | * specific peer endpoint. | |
3929 | * | |
3930 | * The peer endpoint shall be specified by one of the transport addresses | |
3931 | * which defines the endpoint (see Section 1.4). If the local SCTP | |
3932 | * instance has not been initialized, the ASSOCIATE is considered an | |
3933 | * error. | |
3934 | * [This is not relevant for the kernel implementation since we do all | |
3935 | * initialization at boot time. It we hadn't initialized we wouldn't | |
3936 | * get anywhere near this code.] | |
3937 | * | |
3938 | * An association id, which is a local handle to the SCTP association, | |
3939 | * will be returned on successful establishment of the association. If | |
3940 | * SCTP is not able to open an SCTP association with the peer endpoint, | |
3941 | * an error is returned. | |
3942 | * [In the kernel implementation, the struct sctp_association needs to | |
3943 | * be created BEFORE causing this primitive to run.] | |
3944 | * | |
3945 | * Other association parameters may be returned, including the | |
3946 | * complete destination transport addresses of the peer as well as the | |
3947 | * outbound stream count of the local endpoint. One of the transport | |
3948 | * address from the returned destination addresses will be selected by | |
3949 | * the local endpoint as default primary path for sending SCTP packets | |
3950 | * to this peer. The returned "destination transport addr list" can | |
3951 | * be used by the ULP to change the default primary path or to force | |
3952 | * sending a packet to a specific transport address. [All of this | |
3953 | * stuff happens when the INIT ACK arrives. This is a NON-BLOCKING | |
3954 | * function.] | |
3955 | * | |
3956 | * Mandatory attributes: | |
3957 | * | |
3958 | * o local SCTP instance name - obtained from the INITIALIZE operation. | |
3959 | * [This is the argument asoc.] | |
3960 | * o destination transport addr - specified as one of the transport | |
3961 | * addresses of the peer endpoint with which the association is to be | |
3962 | * established. | |
3963 | * [This is asoc->peer.active_path.] | |
3964 | * o outbound stream count - the number of outbound streams the ULP | |
3965 | * would like to open towards this peer endpoint. | |
3966 | * [BUG: This is not currently implemented.] | |
3967 | * Optional attributes: | |
3968 | * | |
3969 | * None. | |
3970 | * | |
3971 | * The return value is a disposition. | |
3972 | */ | |
3973 | sctp_disposition_t sctp_sf_do_prm_asoc(const struct sctp_endpoint *ep, | |
3974 | const struct sctp_association *asoc, | |
3975 | const sctp_subtype_t type, | |
3976 | void *arg, | |
3977 | sctp_cmd_seq_t *commands) | |
3978 | { | |
3979 | struct sctp_chunk *repl; | |
3980 | ||
3981 | /* The comment below says that we enter COOKIE-WAIT AFTER | |
3982 | * sending the INIT, but that doesn't actually work in our | |
3983 | * implementation... | |
3984 | */ | |
3985 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
3986 | SCTP_STATE(SCTP_STATE_COOKIE_WAIT)); | |
3987 | ||
3988 | /* RFC 2960 5.1 Normal Establishment of an Association | |
3989 | * | |
3990 | * A) "A" first sends an INIT chunk to "Z". In the INIT, "A" | |
3991 | * must provide its Verification Tag (Tag_A) in the Initiate | |
3992 | * Tag field. Tag_A SHOULD be a random number in the range of | |
3993 | * 1 to 4294967295 (see 5.3.1 for Tag value selection). ... | |
3994 | */ | |
3995 | ||
3996 | repl = sctp_make_init(asoc, &asoc->base.bind_addr, GFP_ATOMIC, 0); | |
3997 | if (!repl) | |
3998 | goto nomem; | |
3999 | ||
4000 | /* Cast away the const modifier, as we want to just | |
4001 | * rerun it through as a sideffect. | |
4002 | */ | |
4003 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, | |
4004 | SCTP_ASOC((struct sctp_association *) asoc)); | |
4005 | ||
3f7a87d2 FF |
4006 | /* Choose transport for INIT. */ |
4007 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4008 | SCTP_CHUNK(repl)); | |
4009 | ||
1da177e4 LT |
4010 | /* After sending the INIT, "A" starts the T1-init timer and |
4011 | * enters the COOKIE-WAIT state. | |
4012 | */ | |
4013 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4014 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4015 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4016 | return SCTP_DISPOSITION_CONSUME; | |
4017 | ||
4018 | nomem: | |
4019 | return SCTP_DISPOSITION_NOMEM; | |
4020 | } | |
4021 | ||
4022 | /* | |
4023 | * Process the SEND primitive. | |
4024 | * | |
4025 | * Section: 10.1 ULP-to-SCTP | |
4026 | * E) Send | |
4027 | * | |
4028 | * Format: SEND(association id, buffer address, byte count [,context] | |
4029 | * [,stream id] [,life time] [,destination transport address] | |
4030 | * [,unorder flag] [,no-bundle flag] [,payload protocol-id] ) | |
4031 | * -> result | |
4032 | * | |
4033 | * This is the main method to send user data via SCTP. | |
4034 | * | |
4035 | * Mandatory attributes: | |
4036 | * | |
4037 | * o association id - local handle to the SCTP association | |
4038 | * | |
4039 | * o buffer address - the location where the user message to be | |
4040 | * transmitted is stored; | |
4041 | * | |
4042 | * o byte count - The size of the user data in number of bytes; | |
4043 | * | |
4044 | * Optional attributes: | |
4045 | * | |
4046 | * o context - an optional 32 bit integer that will be carried in the | |
4047 | * sending failure notification to the ULP if the transportation of | |
4048 | * this User Message fails. | |
4049 | * | |
4050 | * o stream id - to indicate which stream to send the data on. If not | |
4051 | * specified, stream 0 will be used. | |
4052 | * | |
4053 | * o life time - specifies the life time of the user data. The user data | |
4054 | * will not be sent by SCTP after the life time expires. This | |
4055 | * parameter can be used to avoid efforts to transmit stale | |
4056 | * user messages. SCTP notifies the ULP if the data cannot be | |
4057 | * initiated to transport (i.e. sent to the destination via SCTP's | |
4058 | * send primitive) within the life time variable. However, the | |
4059 | * user data will be transmitted if SCTP has attempted to transmit a | |
4060 | * chunk before the life time expired. | |
4061 | * | |
4062 | * o destination transport address - specified as one of the destination | |
4063 | * transport addresses of the peer endpoint to which this packet | |
4064 | * should be sent. Whenever possible, SCTP should use this destination | |
4065 | * transport address for sending the packets, instead of the current | |
4066 | * primary path. | |
4067 | * | |
4068 | * o unorder flag - this flag, if present, indicates that the user | |
4069 | * would like the data delivered in an unordered fashion to the peer | |
4070 | * (i.e., the U flag is set to 1 on all DATA chunks carrying this | |
4071 | * message). | |
4072 | * | |
4073 | * o no-bundle flag - instructs SCTP not to bundle this user data with | |
4074 | * other outbound DATA chunks. SCTP MAY still bundle even when | |
4075 | * this flag is present, when faced with network congestion. | |
4076 | * | |
4077 | * o payload protocol-id - A 32 bit unsigned integer that is to be | |
4078 | * passed to the peer indicating the type of payload protocol data | |
4079 | * being transmitted. This value is passed as opaque data by SCTP. | |
4080 | * | |
4081 | * The return value is the disposition. | |
4082 | */ | |
4083 | sctp_disposition_t sctp_sf_do_prm_send(const struct sctp_endpoint *ep, | |
4084 | const struct sctp_association *asoc, | |
4085 | const sctp_subtype_t type, | |
4086 | void *arg, | |
4087 | sctp_cmd_seq_t *commands) | |
4088 | { | |
4089 | struct sctp_chunk *chunk = arg; | |
4090 | ||
4091 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
4092 | return SCTP_DISPOSITION_CONSUME; | |
4093 | } | |
4094 | ||
4095 | /* | |
4096 | * Process the SHUTDOWN primitive. | |
4097 | * | |
4098 | * Section: 10.1: | |
4099 | * C) Shutdown | |
4100 | * | |
4101 | * Format: SHUTDOWN(association id) | |
4102 | * -> result | |
4103 | * | |
4104 | * Gracefully closes an association. Any locally queued user data | |
4105 | * will be delivered to the peer. The association will be terminated only | |
4106 | * after the peer acknowledges all the SCTP packets sent. A success code | |
4107 | * will be returned on successful termination of the association. If | |
4108 | * attempting to terminate the association results in a failure, an error | |
4109 | * code shall be returned. | |
4110 | * | |
4111 | * Mandatory attributes: | |
4112 | * | |
4113 | * o association id - local handle to the SCTP association | |
4114 | * | |
4115 | * Optional attributes: | |
4116 | * | |
4117 | * None. | |
4118 | * | |
4119 | * The return value is the disposition. | |
4120 | */ | |
4121 | sctp_disposition_t sctp_sf_do_9_2_prm_shutdown( | |
4122 | const struct sctp_endpoint *ep, | |
4123 | const struct sctp_association *asoc, | |
4124 | const sctp_subtype_t type, | |
4125 | void *arg, | |
4126 | sctp_cmd_seq_t *commands) | |
4127 | { | |
4128 | int disposition; | |
4129 | ||
4130 | /* From 9.2 Shutdown of an Association | |
4131 | * Upon receipt of the SHUTDOWN primitive from its upper | |
4132 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
4133 | * remains there until all outstanding data has been | |
4134 | * acknowledged by its peer. The endpoint accepts no new data | |
4135 | * from its upper layer, but retransmits data to the far end | |
4136 | * if necessary to fill gaps. | |
4137 | */ | |
4138 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4139 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
4140 | ||
4141 | /* sctpimpguide-05 Section 2.12.2 | |
4142 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
4143 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
4144 | */ | |
4145 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4146 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4147 | ||
4148 | disposition = SCTP_DISPOSITION_CONSUME; | |
4149 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
4150 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
4151 | arg, commands); | |
4152 | } | |
4153 | return disposition; | |
4154 | } | |
4155 | ||
4156 | /* | |
4157 | * Process the ABORT primitive. | |
4158 | * | |
4159 | * Section: 10.1: | |
4160 | * C) Abort | |
4161 | * | |
4162 | * Format: Abort(association id [, cause code]) | |
4163 | * -> result | |
4164 | * | |
4165 | * Ungracefully closes an association. Any locally queued user data | |
4166 | * will be discarded and an ABORT chunk is sent to the peer. A success code | |
4167 | * will be returned on successful abortion of the association. If | |
4168 | * attempting to abort the association results in a failure, an error | |
4169 | * code shall be returned. | |
4170 | * | |
4171 | * Mandatory attributes: | |
4172 | * | |
4173 | * o association id - local handle to the SCTP association | |
4174 | * | |
4175 | * Optional attributes: | |
4176 | * | |
4177 | * o cause code - reason of the abort to be passed to the peer | |
4178 | * | |
4179 | * None. | |
4180 | * | |
4181 | * The return value is the disposition. | |
4182 | */ | |
4183 | sctp_disposition_t sctp_sf_do_9_1_prm_abort( | |
4184 | const struct sctp_endpoint *ep, | |
4185 | const struct sctp_association *asoc, | |
4186 | const sctp_subtype_t type, | |
4187 | void *arg, | |
4188 | sctp_cmd_seq_t *commands) | |
4189 | { | |
4190 | /* From 9.1 Abort of an Association | |
4191 | * Upon receipt of the ABORT primitive from its upper | |
4192 | * layer, the endpoint enters CLOSED state and | |
4193 | * discard all outstanding data has been | |
4194 | * acknowledged by its peer. The endpoint accepts no new data | |
4195 | * from its upper layer, but retransmits data to the far end | |
4196 | * if necessary to fill gaps. | |
4197 | */ | |
c164a9ba | 4198 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4199 | sctp_disposition_t retval; |
4200 | ||
4201 | retval = SCTP_DISPOSITION_CONSUME; | |
4202 | ||
c164a9ba | 4203 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4204 | |
4205 | /* Even if we can't send the ABORT due to low memory delete the | |
4206 | * TCB. This is a departure from our typical NOMEM handling. | |
4207 | */ | |
4208 | ||
8de8c873 SS |
4209 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4210 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 LT |
4211 | /* Delete the established association. */ |
4212 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4213 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4214 | |
4215 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4216 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4217 | ||
4218 | return retval; | |
4219 | } | |
4220 | ||
4221 | /* We tried an illegal operation on an association which is closed. */ | |
4222 | sctp_disposition_t sctp_sf_error_closed(const struct sctp_endpoint *ep, | |
4223 | const struct sctp_association *asoc, | |
4224 | const sctp_subtype_t type, | |
4225 | void *arg, | |
4226 | sctp_cmd_seq_t *commands) | |
4227 | { | |
4228 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, SCTP_ERROR(-EINVAL)); | |
4229 | return SCTP_DISPOSITION_CONSUME; | |
4230 | } | |
4231 | ||
4232 | /* We tried an illegal operation on an association which is shutting | |
4233 | * down. | |
4234 | */ | |
4235 | sctp_disposition_t sctp_sf_error_shutdown(const struct sctp_endpoint *ep, | |
4236 | const struct sctp_association *asoc, | |
4237 | const sctp_subtype_t type, | |
4238 | void *arg, | |
4239 | sctp_cmd_seq_t *commands) | |
4240 | { | |
4241 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_ERROR, | |
4242 | SCTP_ERROR(-ESHUTDOWN)); | |
4243 | return SCTP_DISPOSITION_CONSUME; | |
4244 | } | |
4245 | ||
4246 | /* | |
4247 | * sctp_cookie_wait_prm_shutdown | |
4248 | * | |
4249 | * Section: 4 Note: 2 | |
4250 | * Verification Tag: | |
4251 | * Inputs | |
4252 | * (endpoint, asoc) | |
4253 | * | |
4254 | * The RFC does not explicitly address this issue, but is the route through the | |
4255 | * state table when someone issues a shutdown while in COOKIE_WAIT state. | |
4256 | * | |
4257 | * Outputs | |
4258 | * (timers) | |
4259 | */ | |
4260 | sctp_disposition_t sctp_sf_cookie_wait_prm_shutdown( | |
4261 | const struct sctp_endpoint *ep, | |
4262 | const struct sctp_association *asoc, | |
4263 | const sctp_subtype_t type, | |
4264 | void *arg, | |
4265 | sctp_cmd_seq_t *commands) | |
4266 | { | |
4267 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4268 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4269 | ||
4270 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4271 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4272 | ||
4273 | SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS); | |
4274 | ||
4275 | sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); | |
4276 | ||
4277 | return SCTP_DISPOSITION_DELETE_TCB; | |
4278 | } | |
4279 | ||
4280 | /* | |
4281 | * sctp_cookie_echoed_prm_shutdown | |
4282 | * | |
4283 | * Section: 4 Note: 2 | |
4284 | * Verification Tag: | |
4285 | * Inputs | |
4286 | * (endpoint, asoc) | |
4287 | * | |
4288 | * The RFC does not explcitly address this issue, but is the route through the | |
4289 | * state table when someone issues a shutdown while in COOKIE_ECHOED state. | |
4290 | * | |
4291 | * Outputs | |
4292 | * (timers) | |
4293 | */ | |
4294 | sctp_disposition_t sctp_sf_cookie_echoed_prm_shutdown( | |
4295 | const struct sctp_endpoint *ep, | |
4296 | const struct sctp_association *asoc, | |
4297 | const sctp_subtype_t type, | |
4298 | void *arg, sctp_cmd_seq_t *commands) | |
4299 | { | |
4300 | /* There is a single T1 timer, so we should be able to use | |
4301 | * common function with the COOKIE-WAIT state. | |
4302 | */ | |
4303 | return sctp_sf_cookie_wait_prm_shutdown(ep, asoc, type, arg, commands); | |
4304 | } | |
4305 | ||
4306 | /* | |
4307 | * sctp_sf_cookie_wait_prm_abort | |
4308 | * | |
4309 | * Section: 4 Note: 2 | |
4310 | * Verification Tag: | |
4311 | * Inputs | |
4312 | * (endpoint, asoc) | |
4313 | * | |
4314 | * The RFC does not explicitly address this issue, but is the route through the | |
4315 | * state table when someone issues an abort while in COOKIE_WAIT state. | |
4316 | * | |
4317 | * Outputs | |
4318 | * (timers) | |
4319 | */ | |
4320 | sctp_disposition_t sctp_sf_cookie_wait_prm_abort( | |
4321 | const struct sctp_endpoint *ep, | |
4322 | const struct sctp_association *asoc, | |
4323 | const sctp_subtype_t type, | |
4324 | void *arg, | |
4325 | sctp_cmd_seq_t *commands) | |
4326 | { | |
c164a9ba | 4327 | struct sctp_chunk *abort = arg; |
1da177e4 LT |
4328 | sctp_disposition_t retval; |
4329 | ||
4330 | /* Stop T1-init timer */ | |
4331 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4332 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4333 | retval = SCTP_DISPOSITION_CONSUME; | |
4334 | ||
c164a9ba | 4335 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); |
1da177e4 LT |
4336 | |
4337 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4338 | SCTP_STATE(SCTP_STATE_CLOSED)); | |
4339 | ||
4340 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); | |
4341 | ||
4342 | /* Even if we can't send the ABORT due to low memory delete the | |
4343 | * TCB. This is a departure from our typical NOMEM handling. | |
4344 | */ | |
4345 | ||
8de8c873 SS |
4346 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4347 | SCTP_ERROR(ECONNREFUSED)); | |
1da177e4 LT |
4348 | /* Delete the established association. */ |
4349 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, | |
dc251b2b | 4350 | SCTP_PERR(SCTP_ERROR_USER_ABORT)); |
1da177e4 LT |
4351 | |
4352 | return retval; | |
4353 | } | |
4354 | ||
4355 | /* | |
4356 | * sctp_sf_cookie_echoed_prm_abort | |
4357 | * | |
4358 | * Section: 4 Note: 3 | |
4359 | * Verification Tag: | |
4360 | * Inputs | |
4361 | * (endpoint, asoc) | |
4362 | * | |
4363 | * The RFC does not explcitly address this issue, but is the route through the | |
4364 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4365 | * | |
4366 | * Outputs | |
4367 | * (timers) | |
4368 | */ | |
4369 | sctp_disposition_t sctp_sf_cookie_echoed_prm_abort( | |
4370 | const struct sctp_endpoint *ep, | |
4371 | const struct sctp_association *asoc, | |
4372 | const sctp_subtype_t type, | |
4373 | void *arg, | |
4374 | sctp_cmd_seq_t *commands) | |
4375 | { | |
4376 | /* There is a single T1 timer, so we should be able to use | |
4377 | * common function with the COOKIE-WAIT state. | |
4378 | */ | |
4379 | return sctp_sf_cookie_wait_prm_abort(ep, asoc, type, arg, commands); | |
4380 | } | |
4381 | ||
4382 | /* | |
4383 | * sctp_sf_shutdown_pending_prm_abort | |
4384 | * | |
4385 | * Inputs | |
4386 | * (endpoint, asoc) | |
4387 | * | |
4388 | * The RFC does not explicitly address this issue, but is the route through the | |
4389 | * state table when someone issues an abort while in SHUTDOWN-PENDING state. | |
4390 | * | |
4391 | * Outputs | |
4392 | * (timers) | |
4393 | */ | |
4394 | sctp_disposition_t sctp_sf_shutdown_pending_prm_abort( | |
4395 | const struct sctp_endpoint *ep, | |
4396 | const struct sctp_association *asoc, | |
4397 | const sctp_subtype_t type, | |
4398 | void *arg, | |
4399 | sctp_cmd_seq_t *commands) | |
4400 | { | |
4401 | /* Stop the T5-shutdown guard timer. */ | |
4402 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4403 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4404 | ||
4405 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4406 | } | |
4407 | ||
4408 | /* | |
4409 | * sctp_sf_shutdown_sent_prm_abort | |
4410 | * | |
4411 | * Inputs | |
4412 | * (endpoint, asoc) | |
4413 | * | |
4414 | * The RFC does not explicitly address this issue, but is the route through the | |
4415 | * state table when someone issues an abort while in SHUTDOWN-SENT state. | |
4416 | * | |
4417 | * Outputs | |
4418 | * (timers) | |
4419 | */ | |
4420 | sctp_disposition_t sctp_sf_shutdown_sent_prm_abort( | |
4421 | const struct sctp_endpoint *ep, | |
4422 | const struct sctp_association *asoc, | |
4423 | const sctp_subtype_t type, | |
4424 | void *arg, | |
4425 | sctp_cmd_seq_t *commands) | |
4426 | { | |
4427 | /* Stop the T2-shutdown timer. */ | |
4428 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4429 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4430 | ||
4431 | /* Stop the T5-shutdown guard timer. */ | |
4432 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4433 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
4434 | ||
4435 | return sctp_sf_do_9_1_prm_abort(ep, asoc, type, arg, commands); | |
4436 | } | |
4437 | ||
4438 | /* | |
4439 | * sctp_sf_cookie_echoed_prm_abort | |
4440 | * | |
4441 | * Inputs | |
4442 | * (endpoint, asoc) | |
4443 | * | |
4444 | * The RFC does not explcitly address this issue, but is the route through the | |
4445 | * state table when someone issues an abort while in COOKIE_ECHOED state. | |
4446 | * | |
4447 | * Outputs | |
4448 | * (timers) | |
4449 | */ | |
4450 | sctp_disposition_t sctp_sf_shutdown_ack_sent_prm_abort( | |
4451 | const struct sctp_endpoint *ep, | |
4452 | const struct sctp_association *asoc, | |
4453 | const sctp_subtype_t type, | |
4454 | void *arg, | |
4455 | sctp_cmd_seq_t *commands) | |
4456 | { | |
4457 | /* The same T2 timer, so we should be able to use | |
4458 | * common function with the SHUTDOWN-SENT state. | |
4459 | */ | |
4460 | return sctp_sf_shutdown_sent_prm_abort(ep, asoc, type, arg, commands); | |
4461 | } | |
4462 | ||
4463 | /* | |
4464 | * Process the REQUESTHEARTBEAT primitive | |
4465 | * | |
4466 | * 10.1 ULP-to-SCTP | |
4467 | * J) Request Heartbeat | |
4468 | * | |
4469 | * Format: REQUESTHEARTBEAT(association id, destination transport address) | |
4470 | * | |
4471 | * -> result | |
4472 | * | |
4473 | * Instructs the local endpoint to perform a HeartBeat on the specified | |
4474 | * destination transport address of the given association. The returned | |
4475 | * result should indicate whether the transmission of the HEARTBEAT | |
4476 | * chunk to the destination address is successful. | |
4477 | * | |
4478 | * Mandatory attributes: | |
4479 | * | |
4480 | * o association id - local handle to the SCTP association | |
4481 | * | |
4482 | * o destination transport address - the transport address of the | |
4483 | * association on which a heartbeat should be issued. | |
4484 | */ | |
4485 | sctp_disposition_t sctp_sf_do_prm_requestheartbeat( | |
4486 | const struct sctp_endpoint *ep, | |
4487 | const struct sctp_association *asoc, | |
4488 | const sctp_subtype_t type, | |
4489 | void *arg, | |
4490 | sctp_cmd_seq_t *commands) | |
4491 | { | |
fb78525a VY |
4492 | if (SCTP_DISPOSITION_NOMEM == sctp_sf_heartbeat(ep, asoc, type, |
4493 | (struct sctp_transport *)arg, commands)) | |
4494 | return SCTP_DISPOSITION_NOMEM; | |
4495 | ||
4496 | /* | |
4497 | * RFC 2960 (bis), section 8.3 | |
4498 | * | |
4499 | * D) Request an on-demand HEARTBEAT on a specific destination | |
4500 | * transport address of a given association. | |
4501 | * | |
4502 | * The endpoint should increment the respective error counter of | |
4503 | * the destination transport address each time a HEARTBEAT is sent | |
4504 | * to that address and not acknowledged within one RTO. | |
4505 | * | |
4506 | */ | |
4507 | sctp_add_cmd_sf(commands, SCTP_CMD_TRANSPORT_RESET, | |
4508 | SCTP_TRANSPORT(arg)); | |
4509 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
4510 | } |
4511 | ||
4512 | /* | |
4513 | * ADDIP Section 4.1 ASCONF Chunk Procedures | |
4514 | * When an endpoint has an ASCONF signaled change to be sent to the | |
4515 | * remote endpoint it should do A1 to A9 | |
4516 | */ | |
4517 | sctp_disposition_t sctp_sf_do_prm_asconf(const struct sctp_endpoint *ep, | |
4518 | const struct sctp_association *asoc, | |
4519 | const sctp_subtype_t type, | |
4520 | void *arg, | |
4521 | sctp_cmd_seq_t *commands) | |
4522 | { | |
4523 | struct sctp_chunk *chunk = arg; | |
4524 | ||
4525 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
4526 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4527 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
4528 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk)); | |
4529 | return SCTP_DISPOSITION_CONSUME; | |
4530 | } | |
4531 | ||
4532 | /* | |
4533 | * Ignore the primitive event | |
4534 | * | |
4535 | * The return value is the disposition of the primitive. | |
4536 | */ | |
4537 | sctp_disposition_t sctp_sf_ignore_primitive( | |
4538 | const struct sctp_endpoint *ep, | |
4539 | const struct sctp_association *asoc, | |
4540 | const sctp_subtype_t type, | |
4541 | void *arg, | |
4542 | sctp_cmd_seq_t *commands) | |
4543 | { | |
4544 | SCTP_DEBUG_PRINTK("Primitive type %d is ignored.\n", type.primitive); | |
4545 | return SCTP_DISPOSITION_DISCARD; | |
4546 | } | |
4547 | ||
4548 | /*************************************************************************** | |
4549 | * These are the state functions for the OTHER events. | |
4550 | ***************************************************************************/ | |
4551 | ||
4552 | /* | |
4553 | * Start the shutdown negotiation. | |
4554 | * | |
4555 | * From Section 9.2: | |
4556 | * Once all its outstanding data has been acknowledged, the endpoint | |
4557 | * shall send a SHUTDOWN chunk to its peer including in the Cumulative | |
4558 | * TSN Ack field the last sequential TSN it has received from the peer. | |
4559 | * It shall then start the T2-shutdown timer and enter the SHUTDOWN-SENT | |
4560 | * state. If the timer expires, the endpoint must re-send the SHUTDOWN | |
4561 | * with the updated last sequential TSN received from its peer. | |
4562 | * | |
4563 | * The return value is the disposition. | |
4564 | */ | |
4565 | sctp_disposition_t sctp_sf_do_9_2_start_shutdown( | |
4566 | const struct sctp_endpoint *ep, | |
4567 | const struct sctp_association *asoc, | |
4568 | const sctp_subtype_t type, | |
4569 | void *arg, | |
4570 | sctp_cmd_seq_t *commands) | |
4571 | { | |
4572 | struct sctp_chunk *reply; | |
4573 | ||
4574 | /* Once all its outstanding data has been acknowledged, the | |
4575 | * endpoint shall send a SHUTDOWN chunk to its peer including | |
4576 | * in the Cumulative TSN Ack field the last sequential TSN it | |
4577 | * has received from the peer. | |
4578 | */ | |
4579 | reply = sctp_make_shutdown(asoc, NULL); | |
4580 | if (!reply) | |
4581 | goto nomem; | |
4582 | ||
4583 | /* Set the transport for the SHUTDOWN chunk and the timeout for the | |
4584 | * T2-shutdown timer. | |
4585 | */ | |
4586 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
4587 | ||
4588 | /* It shall then start the T2-shutdown timer */ | |
4589 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, | |
4590 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4591 | ||
4592 | if (asoc->autoclose) | |
4593 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4594 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
4595 | ||
4596 | /* and enter the SHUTDOWN-SENT state. */ | |
4597 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4598 | SCTP_STATE(SCTP_STATE_SHUTDOWN_SENT)); | |
4599 | ||
4600 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
4601 | * | |
4602 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 4603 | * or SHUTDOWN-ACK. |
1da177e4 LT |
4604 | */ |
4605 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
4606 | ||
4607 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
4608 | ||
4609 | return SCTP_DISPOSITION_CONSUME; | |
4610 | ||
4611 | nomem: | |
4612 | return SCTP_DISPOSITION_NOMEM; | |
4613 | } | |
4614 | ||
4615 | /* | |
4616 | * Generate a SHUTDOWN ACK now that everything is SACK'd. | |
4617 | * | |
4618 | * From Section 9.2: | |
4619 | * | |
4620 | * If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
4621 | * shall send a SHUTDOWN ACK and start a T2-shutdown timer of its own, | |
4622 | * entering the SHUTDOWN-ACK-SENT state. If the timer expires, the | |
4623 | * endpoint must re-send the SHUTDOWN ACK. | |
4624 | * | |
4625 | * The return value is the disposition. | |
4626 | */ | |
4627 | sctp_disposition_t sctp_sf_do_9_2_shutdown_ack( | |
4628 | const struct sctp_endpoint *ep, | |
4629 | const struct sctp_association *asoc, | |
4630 | const sctp_subtype_t type, | |
4631 | void *arg, | |
4632 | sctp_cmd_seq_t *commands) | |
4633 | { | |
4634 | struct sctp_chunk *chunk = (struct sctp_chunk *) arg; | |
4635 | struct sctp_chunk *reply; | |
4636 | ||
4637 | /* There are 2 ways of getting here: | |
4638 | * 1) called in response to a SHUTDOWN chunk | |
4639 | * 2) called when SCTP_EVENT_NO_PENDING_TSN event is issued. | |
4640 | * | |
4641 | * For the case (2), the arg parameter is set to NULL. We need | |
4642 | * to check that we have a chunk before accessing it's fields. | |
4643 | */ | |
4644 | if (chunk) { | |
4645 | if (!sctp_vtag_verify(chunk, asoc)) | |
4646 | return sctp_sf_pdiscard(ep, asoc, type, arg, commands); | |
4647 | ||
4648 | /* Make sure that the SHUTDOWN chunk has a valid length. */ | |
4649 | if (!sctp_chunk_length_valid(chunk, sizeof(struct sctp_shutdown_chunk_t))) | |
4650 | return sctp_sf_violation_chunklen(ep, asoc, type, arg, | |
4651 | commands); | |
4652 | } | |
4653 | ||
4654 | /* If it has no more outstanding DATA chunks, the SHUTDOWN receiver | |
4655 | * shall send a SHUTDOWN ACK ... | |
4656 | */ | |
4657 | reply = sctp_make_shutdown_ack(asoc, chunk); | |
4658 | if (!reply) | |
4659 | goto nomem; | |
4660 | ||
4661 | /* Set the transport for the SHUTDOWN ACK chunk and the timeout for | |
4662 | * the T2-shutdown timer. | |
4663 | */ | |
4664 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
4665 | ||
4666 | /* and start/restart a T2-shutdown timer of its own, */ | |
4667 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
4668 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4669 | ||
4670 | if (asoc->autoclose) | |
4671 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
4672 | SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE)); | |
4673 | ||
4674 | /* Enter the SHUTDOWN-ACK-SENT state. */ | |
4675 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
4676 | SCTP_STATE(SCTP_STATE_SHUTDOWN_ACK_SENT)); | |
4677 | ||
4678 | /* sctp-implguide 2.10 Issues with Heartbeating and failover | |
4679 | * | |
4680 | * HEARTBEAT ... is discontinued after sending either SHUTDOWN | |
d808ad9a | 4681 | * or SHUTDOWN-ACK. |
1da177e4 LT |
4682 | */ |
4683 | sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_STOP, SCTP_NULL()); | |
4684 | ||
4685 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
4686 | ||
4687 | return SCTP_DISPOSITION_CONSUME; | |
4688 | ||
4689 | nomem: | |
4690 | return SCTP_DISPOSITION_NOMEM; | |
4691 | } | |
4692 | ||
4693 | /* | |
4694 | * Ignore the event defined as other | |
4695 | * | |
4696 | * The return value is the disposition of the event. | |
4697 | */ | |
4698 | sctp_disposition_t sctp_sf_ignore_other(const struct sctp_endpoint *ep, | |
4699 | const struct sctp_association *asoc, | |
4700 | const sctp_subtype_t type, | |
4701 | void *arg, | |
4702 | sctp_cmd_seq_t *commands) | |
4703 | { | |
4704 | SCTP_DEBUG_PRINTK("The event other type %d is ignored\n", type.other); | |
4705 | return SCTP_DISPOSITION_DISCARD; | |
4706 | } | |
4707 | ||
4708 | /************************************************************ | |
4709 | * These are the state functions for handling timeout events. | |
4710 | ************************************************************/ | |
4711 | ||
4712 | /* | |
4713 | * RTX Timeout | |
4714 | * | |
4715 | * Section: 6.3.3 Handle T3-rtx Expiration | |
4716 | * | |
4717 | * Whenever the retransmission timer T3-rtx expires for a destination | |
4718 | * address, do the following: | |
4719 | * [See below] | |
4720 | * | |
4721 | * The return value is the disposition of the chunk. | |
4722 | */ | |
4723 | sctp_disposition_t sctp_sf_do_6_3_3_rtx(const struct sctp_endpoint *ep, | |
4724 | const struct sctp_association *asoc, | |
4725 | const sctp_subtype_t type, | |
4726 | void *arg, | |
4727 | sctp_cmd_seq_t *commands) | |
4728 | { | |
4729 | struct sctp_transport *transport = arg; | |
4730 | ||
ac0b0462 SS |
4731 | SCTP_INC_STATS(SCTP_MIB_T3_RTX_EXPIREDS); |
4732 | ||
1da177e4 | 4733 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
4734 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4735 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
4736 | /* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
4737 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4738 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
4739 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
4740 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4741 | return SCTP_DISPOSITION_DELETE_TCB; | |
4742 | } | |
4743 | ||
4744 | /* E1) For the destination address for which the timer | |
4745 | * expires, adjust its ssthresh with rules defined in Section | |
4746 | * 7.2.3 and set the cwnd <- MTU. | |
4747 | */ | |
4748 | ||
4749 | /* E2) For the destination address for which the timer | |
4750 | * expires, set RTO <- RTO * 2 ("back off the timer"). The | |
4751 | * maximum value discussed in rule C7 above (RTO.max) may be | |
4752 | * used to provide an upper bound to this doubling operation. | |
4753 | */ | |
4754 | ||
4755 | /* E3) Determine how many of the earliest (i.e., lowest TSN) | |
4756 | * outstanding DATA chunks for the address for which the | |
4757 | * T3-rtx has expired will fit into a single packet, subject | |
4758 | * to the MTU constraint for the path corresponding to the | |
4759 | * destination transport address to which the retransmission | |
4760 | * is being sent (this may be different from the address for | |
4761 | * which the timer expires [see Section 6.4]). Call this | |
4762 | * value K. Bundle and retransmit those K DATA chunks in a | |
4763 | * single packet to the destination endpoint. | |
4764 | * | |
4765 | * Note: Any DATA chunks that were sent to the address for | |
4766 | * which the T3-rtx timer expired but did not fit in one MTU | |
4767 | * (rule E3 above), should be marked for retransmission and | |
4768 | * sent as soon as cwnd allows (normally when a SACK arrives). | |
4769 | */ | |
4770 | ||
1da177e4 LT |
4771 | /* Do some failure management (Section 8.2). */ |
4772 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
4773 | ||
1845a579 VY |
4774 | /* NB: Rules E4 and F1 are implicit in R1. */ |
4775 | sctp_add_cmd_sf(commands, SCTP_CMD_RETRAN, SCTP_TRANSPORT(transport)); | |
4776 | ||
1da177e4 LT |
4777 | return SCTP_DISPOSITION_CONSUME; |
4778 | } | |
4779 | ||
4780 | /* | |
4781 | * Generate delayed SACK on timeout | |
4782 | * | |
4783 | * Section: 6.2 Acknowledgement on Reception of DATA Chunks | |
4784 | * | |
4785 | * The guidelines on delayed acknowledgement algorithm specified in | |
4786 | * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, an | |
4787 | * acknowledgement SHOULD be generated for at least every second packet | |
4788 | * (not every second DATA chunk) received, and SHOULD be generated | |
4789 | * within 200 ms of the arrival of any unacknowledged DATA chunk. In | |
4790 | * some situations it may be beneficial for an SCTP transmitter to be | |
4791 | * more conservative than the algorithms detailed in this document | |
4792 | * allow. However, an SCTP transmitter MUST NOT be more aggressive than | |
4793 | * the following algorithms allow. | |
4794 | */ | |
4795 | sctp_disposition_t sctp_sf_do_6_2_sack(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 | { | |
ac0b0462 | 4801 | SCTP_INC_STATS(SCTP_MIB_DELAY_SACK_EXPIREDS); |
1da177e4 LT |
4802 | sctp_add_cmd_sf(commands, SCTP_CMD_GEN_SACK, SCTP_FORCE()); |
4803 | return SCTP_DISPOSITION_CONSUME; | |
4804 | } | |
4805 | ||
4806 | /* | |
3f7a87d2 | 4807 | * sctp_sf_t1_init_timer_expire |
1da177e4 LT |
4808 | * |
4809 | * Section: 4 Note: 2 | |
4810 | * Verification Tag: | |
4811 | * Inputs | |
4812 | * (endpoint, asoc) | |
4813 | * | |
4814 | * RFC 2960 Section 4 Notes | |
4815 | * 2) If the T1-init timer expires, the endpoint MUST retransmit INIT | |
4816 | * and re-start the T1-init timer without changing state. This MUST | |
4817 | * be repeated up to 'Max.Init.Retransmits' times. After that, the | |
4818 | * endpoint MUST abort the initialization process and report the | |
4819 | * error to SCTP user. | |
4820 | * | |
3f7a87d2 FF |
4821 | * Outputs |
4822 | * (timers, events) | |
4823 | * | |
4824 | */ | |
4825 | sctp_disposition_t sctp_sf_t1_init_timer_expire(const struct sctp_endpoint *ep, | |
4826 | const struct sctp_association *asoc, | |
4827 | const sctp_subtype_t type, | |
4828 | void *arg, | |
4829 | sctp_cmd_seq_t *commands) | |
4830 | { | |
4831 | struct sctp_chunk *repl = NULL; | |
4832 | struct sctp_bind_addr *bp; | |
4833 | int attempts = asoc->init_err_counter + 1; | |
4834 | ||
4835 | SCTP_DEBUG_PRINTK("Timer T1 expired (INIT).\n"); | |
ac0b0462 | 4836 | SCTP_INC_STATS(SCTP_MIB_T1_INIT_EXPIREDS); |
3f7a87d2 | 4837 | |
81845c21 | 4838 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 FF |
4839 | bp = (struct sctp_bind_addr *) &asoc->base.bind_addr; |
4840 | repl = sctp_make_init(asoc, bp, GFP_ATOMIC, 0); | |
4841 | if (!repl) | |
4842 | return SCTP_DISPOSITION_NOMEM; | |
4843 | ||
4844 | /* Choose transport for INIT. */ | |
4845 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_CHOOSE_TRANSPORT, | |
4846 | SCTP_CHUNK(repl)); | |
4847 | ||
4848 | /* Issue a sideeffect to do the needed accounting. */ | |
4849 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_RESTART, | |
4850 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); | |
4851 | ||
4852 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); | |
4853 | } else { | |
4854 | SCTP_DEBUG_PRINTK("Giving up on INIT, attempts: %d" | |
4855 | " max_init_attempts: %d\n", | |
4856 | attempts, asoc->max_init_attempts); | |
8de8c873 SS |
4857 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4858 | SCTP_ERROR(ETIMEDOUT)); | |
3f7a87d2 | 4859 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 4860 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
3f7a87d2 FF |
4861 | return SCTP_DISPOSITION_DELETE_TCB; |
4862 | } | |
4863 | ||
4864 | return SCTP_DISPOSITION_CONSUME; | |
4865 | } | |
4866 | ||
4867 | /* | |
4868 | * sctp_sf_t1_cookie_timer_expire | |
4869 | * | |
4870 | * Section: 4 Note: 2 | |
4871 | * Verification Tag: | |
4872 | * Inputs | |
4873 | * (endpoint, asoc) | |
4874 | * | |
4875 | * RFC 2960 Section 4 Notes | |
4876 | * 3) If the T1-cookie timer expires, the endpoint MUST retransmit | |
1da177e4 LT |
4877 | * COOKIE ECHO and re-start the T1-cookie timer without changing |
4878 | * state. This MUST be repeated up to 'Max.Init.Retransmits' times. | |
4879 | * After that, the endpoint MUST abort the initialization process and | |
4880 | * report the error to SCTP user. | |
4881 | * | |
4882 | * Outputs | |
4883 | * (timers, events) | |
4884 | * | |
4885 | */ | |
3f7a87d2 | 4886 | sctp_disposition_t sctp_sf_t1_cookie_timer_expire(const struct sctp_endpoint *ep, |
1da177e4 LT |
4887 | const struct sctp_association *asoc, |
4888 | const sctp_subtype_t type, | |
4889 | void *arg, | |
4890 | sctp_cmd_seq_t *commands) | |
4891 | { | |
3f7a87d2 FF |
4892 | struct sctp_chunk *repl = NULL; |
4893 | int attempts = asoc->init_err_counter + 1; | |
1da177e4 | 4894 | |
3f7a87d2 | 4895 | SCTP_DEBUG_PRINTK("Timer T1 expired (COOKIE-ECHO).\n"); |
ac0b0462 | 4896 | SCTP_INC_STATS(SCTP_MIB_T1_COOKIE_EXPIREDS); |
1da177e4 | 4897 | |
81845c21 | 4898 | if (attempts <= asoc->max_init_attempts) { |
3f7a87d2 | 4899 | repl = sctp_make_cookie_echo(asoc, NULL); |
1da177e4 | 4900 | if (!repl) |
3f7a87d2 | 4901 | return SCTP_DISPOSITION_NOMEM; |
1da177e4 LT |
4902 | |
4903 | /* Issue a sideeffect to do the needed accounting. */ | |
3f7a87d2 FF |
4904 | sctp_add_cmd_sf(commands, SCTP_CMD_COOKIEECHO_RESTART, |
4905 | SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); | |
4906 | ||
1da177e4 LT |
4907 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl)); |
4908 | } else { | |
8de8c873 SS |
4909 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4910 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 4911 | sctp_add_cmd_sf(commands, SCTP_CMD_INIT_FAILED, |
dc251b2b | 4912 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
4913 | return SCTP_DISPOSITION_DELETE_TCB; |
4914 | } | |
4915 | ||
4916 | return SCTP_DISPOSITION_CONSUME; | |
1da177e4 LT |
4917 | } |
4918 | ||
4919 | /* RFC2960 9.2 If the timer expires, the endpoint must re-send the SHUTDOWN | |
4920 | * with the updated last sequential TSN received from its peer. | |
4921 | * | |
4922 | * An endpoint should limit the number of retransmissions of the | |
4923 | * SHUTDOWN chunk to the protocol parameter 'Association.Max.Retrans'. | |
4924 | * If this threshold is exceeded the endpoint should destroy the TCB and | |
4925 | * MUST report the peer endpoint unreachable to the upper layer (and | |
4926 | * thus the association enters the CLOSED state). The reception of any | |
4927 | * packet from its peer (i.e. as the peer sends all of its queued DATA | |
4928 | * chunks) should clear the endpoint's retransmission count and restart | |
4929 | * the T2-Shutdown timer, giving its peer ample opportunity to transmit | |
4930 | * all of its queued DATA chunks that have not yet been sent. | |
4931 | */ | |
4932 | sctp_disposition_t sctp_sf_t2_timer_expire(const struct sctp_endpoint *ep, | |
4933 | const struct sctp_association *asoc, | |
4934 | const sctp_subtype_t type, | |
4935 | void *arg, | |
4936 | sctp_cmd_seq_t *commands) | |
4937 | { | |
4938 | struct sctp_chunk *reply = NULL; | |
4939 | ||
4940 | SCTP_DEBUG_PRINTK("Timer T2 expired.\n"); | |
ac0b0462 SS |
4941 | SCTP_INC_STATS(SCTP_MIB_T2_SHUTDOWN_EXPIREDS); |
4942 | ||
1da177e4 | 4943 | if (asoc->overall_error_count >= asoc->max_retrans) { |
8de8c873 SS |
4944 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
4945 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 LT |
4946 | /* Note: CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */ |
4947 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, | |
5be291fe | 4948 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
4949 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
4950 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
4951 | return SCTP_DISPOSITION_DELETE_TCB; | |
4952 | } | |
4953 | ||
4954 | switch (asoc->state) { | |
4955 | case SCTP_STATE_SHUTDOWN_SENT: | |
4956 | reply = sctp_make_shutdown(asoc, NULL); | |
4957 | break; | |
4958 | ||
4959 | case SCTP_STATE_SHUTDOWN_ACK_SENT: | |
4960 | reply = sctp_make_shutdown_ack(asoc, NULL); | |
4961 | break; | |
4962 | ||
4963 | default: | |
4964 | BUG(); | |
4965 | break; | |
3ff50b79 | 4966 | } |
1da177e4 LT |
4967 | |
4968 | if (!reply) | |
4969 | goto nomem; | |
4970 | ||
4971 | /* Do some failure management (Section 8.2). */ | |
4972 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, | |
4973 | SCTP_TRANSPORT(asoc->shutdown_last_sent_to)); | |
4974 | ||
4975 | /* Set the transport for the SHUTDOWN/ACK chunk and the timeout for | |
4976 | * the T2-shutdown timer. | |
4977 | */ | |
4978 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T2, SCTP_CHUNK(reply)); | |
4979 | ||
4980 | /* Restart the T2-shutdown timer. */ | |
4981 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
4982 | SCTP_TO(SCTP_EVENT_TIMEOUT_T2_SHUTDOWN)); | |
4983 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
4984 | return SCTP_DISPOSITION_CONSUME; | |
4985 | ||
4986 | nomem: | |
4987 | return SCTP_DISPOSITION_NOMEM; | |
4988 | } | |
4989 | ||
4990 | /* | |
4991 | * ADDIP Section 4.1 ASCONF CHunk Procedures | |
4992 | * If the T4 RTO timer expires the endpoint should do B1 to B5 | |
4993 | */ | |
4994 | sctp_disposition_t sctp_sf_t4_timer_expire( | |
4995 | const struct sctp_endpoint *ep, | |
4996 | const struct sctp_association *asoc, | |
4997 | const sctp_subtype_t type, | |
4998 | void *arg, | |
4999 | sctp_cmd_seq_t *commands) | |
5000 | { | |
5001 | struct sctp_chunk *chunk = asoc->addip_last_asconf; | |
5002 | struct sctp_transport *transport = chunk->transport; | |
5003 | ||
ac0b0462 SS |
5004 | SCTP_INC_STATS(SCTP_MIB_T4_RTO_EXPIREDS); |
5005 | ||
1da177e4 LT |
5006 | /* ADDIP 4.1 B1) Increment the error counters and perform path failure |
5007 | * detection on the appropriate destination address as defined in | |
5008 | * RFC2960 [5] section 8.1 and 8.2. | |
5009 | */ | |
5010 | sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport)); | |
5011 | ||
5012 | /* Reconfig T4 timer and transport. */ | |
5013 | sctp_add_cmd_sf(commands, SCTP_CMD_SETUP_T4, SCTP_CHUNK(chunk)); | |
5014 | ||
5015 | /* ADDIP 4.1 B2) Increment the association error counters and perform | |
5016 | * endpoint failure detection on the association as defined in | |
5017 | * RFC2960 [5] section 8.1 and 8.2. | |
5018 | * association error counter is incremented in SCTP_CMD_STRIKE. | |
5019 | */ | |
5020 | if (asoc->overall_error_count >= asoc->max_retrans) { | |
5021 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, | |
5022 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
8de8c873 SS |
5023 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5024 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5025 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5026 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5027 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5028 | SCTP_INC_STATS(SCTP_MIB_CURRESTAB); | |
5029 | return SCTP_DISPOSITION_ABORT; | |
5030 | } | |
5031 | ||
5032 | /* ADDIP 4.1 B3) Back-off the destination address RTO value to which | |
5033 | * the ASCONF chunk was sent by doubling the RTO timer value. | |
5034 | * This is done in SCTP_CMD_STRIKE. | |
5035 | */ | |
5036 | ||
5037 | /* ADDIP 4.1 B4) Re-transmit the ASCONF Chunk last sent and if possible | |
5038 | * choose an alternate destination address (please refer to RFC2960 | |
5039 | * [5] section 6.4.1). An endpoint MUST NOT add new parameters to this | |
d808ad9a | 5040 | * chunk, it MUST be the same (including its serial number) as the last |
1da177e4 LT |
5041 | * ASCONF sent. |
5042 | */ | |
5043 | sctp_chunk_hold(asoc->addip_last_asconf); | |
5044 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5045 | SCTP_CHUNK(asoc->addip_last_asconf)); | |
5046 | ||
5047 | /* ADDIP 4.1 B5) Restart the T-4 RTO timer. Note that if a different | |
5048 | * destination is selected, then the RTO used will be that of the new | |
5049 | * destination address. | |
5050 | */ | |
5051 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, | |
5052 | SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); | |
5053 | ||
5054 | return SCTP_DISPOSITION_CONSUME; | |
5055 | } | |
5056 | ||
5057 | /* sctpimpguide-05 Section 2.12.2 | |
5058 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5059 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
5060 | * At the expiration of this timer the sender SHOULD abort the association | |
5061 | * by sending an ABORT chunk. | |
5062 | */ | |
5063 | sctp_disposition_t sctp_sf_t5_timer_expire(const struct sctp_endpoint *ep, | |
5064 | const struct sctp_association *asoc, | |
5065 | const sctp_subtype_t type, | |
5066 | void *arg, | |
5067 | sctp_cmd_seq_t *commands) | |
5068 | { | |
5069 | struct sctp_chunk *reply = NULL; | |
5070 | ||
5071 | SCTP_DEBUG_PRINTK("Timer T5 expired.\n"); | |
ac0b0462 | 5072 | SCTP_INC_STATS(SCTP_MIB_T5_SHUTDOWN_GUARD_EXPIREDS); |
1da177e4 LT |
5073 | |
5074 | reply = sctp_make_abort(asoc, NULL, 0); | |
5075 | if (!reply) | |
5076 | goto nomem; | |
5077 | ||
5078 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply)); | |
8de8c873 SS |
5079 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5080 | SCTP_ERROR(ETIMEDOUT)); | |
1da177e4 | 5081 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5082 | SCTP_PERR(SCTP_ERROR_NO_ERROR)); |
1da177e4 LT |
5083 | |
5084 | return SCTP_DISPOSITION_DELETE_TCB; | |
5085 | nomem: | |
5086 | return SCTP_DISPOSITION_NOMEM; | |
5087 | } | |
5088 | ||
5089 | /* Handle expiration of AUTOCLOSE timer. When the autoclose timer expires, | |
5090 | * the association is automatically closed by starting the shutdown process. | |
5091 | * The work that needs to be done is same as when SHUTDOWN is initiated by | |
5092 | * the user. So this routine looks same as sctp_sf_do_9_2_prm_shutdown(). | |
5093 | */ | |
5094 | sctp_disposition_t sctp_sf_autoclose_timer_expire( | |
5095 | const struct sctp_endpoint *ep, | |
5096 | const struct sctp_association *asoc, | |
5097 | const sctp_subtype_t type, | |
5098 | void *arg, | |
5099 | sctp_cmd_seq_t *commands) | |
5100 | { | |
5101 | int disposition; | |
5102 | ||
ac0b0462 SS |
5103 | SCTP_INC_STATS(SCTP_MIB_AUTOCLOSE_EXPIREDS); |
5104 | ||
1da177e4 LT |
5105 | /* From 9.2 Shutdown of an Association |
5106 | * Upon receipt of the SHUTDOWN primitive from its upper | |
5107 | * layer, the endpoint enters SHUTDOWN-PENDING state and | |
5108 | * remains there until all outstanding data has been | |
5109 | * acknowledged by its peer. The endpoint accepts no new data | |
5110 | * from its upper layer, but retransmits data to the far end | |
5111 | * if necessary to fill gaps. | |
5112 | */ | |
5113 | sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, | |
5114 | SCTP_STATE(SCTP_STATE_SHUTDOWN_PENDING)); | |
5115 | ||
5116 | /* sctpimpguide-05 Section 2.12.2 | |
5117 | * The sender of the SHUTDOWN MAY also start an overall guard timer | |
5118 | * 'T5-shutdown-guard' to bound the overall time for shutdown sequence. | |
d808ad9a | 5119 | */ |
1da177e4 LT |
5120 | sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START, |
5121 | SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD)); | |
5122 | disposition = SCTP_DISPOSITION_CONSUME; | |
5123 | if (sctp_outq_is_empty(&asoc->outqueue)) { | |
5124 | disposition = sctp_sf_do_9_2_start_shutdown(ep, asoc, type, | |
5125 | arg, commands); | |
5126 | } | |
5127 | return disposition; | |
5128 | } | |
5129 | ||
5130 | /***************************************************************************** | |
5131 | * These are sa state functions which could apply to all types of events. | |
5132 | ****************************************************************************/ | |
5133 | ||
5134 | /* | |
5135 | * This table entry is not implemented. | |
5136 | * | |
5137 | * Inputs | |
5138 | * (endpoint, asoc, chunk) | |
5139 | * | |
5140 | * The return value is the disposition of the chunk. | |
5141 | */ | |
5142 | sctp_disposition_t sctp_sf_not_impl(const struct sctp_endpoint *ep, | |
5143 | const struct sctp_association *asoc, | |
5144 | const sctp_subtype_t type, | |
5145 | void *arg, | |
5146 | sctp_cmd_seq_t *commands) | |
5147 | { | |
5148 | return SCTP_DISPOSITION_NOT_IMPL; | |
5149 | } | |
5150 | ||
5151 | /* | |
5152 | * This table entry represents a bug. | |
5153 | * | |
5154 | * Inputs | |
5155 | * (endpoint, asoc, chunk) | |
5156 | * | |
5157 | * The return value is the disposition of the chunk. | |
5158 | */ | |
5159 | sctp_disposition_t sctp_sf_bug(const struct sctp_endpoint *ep, | |
5160 | const struct sctp_association *asoc, | |
5161 | const sctp_subtype_t type, | |
5162 | void *arg, | |
5163 | sctp_cmd_seq_t *commands) | |
5164 | { | |
5165 | return SCTP_DISPOSITION_BUG; | |
5166 | } | |
5167 | ||
5168 | /* | |
5169 | * This table entry represents the firing of a timer in the wrong state. | |
5170 | * Since timer deletion cannot be guaranteed a timer 'may' end up firing | |
5171 | * when the association is in the wrong state. This event should | |
5172 | * be ignored, so as to prevent any rearming of the timer. | |
5173 | * | |
5174 | * Inputs | |
5175 | * (endpoint, asoc, chunk) | |
5176 | * | |
5177 | * The return value is the disposition of the chunk. | |
5178 | */ | |
5179 | sctp_disposition_t sctp_sf_timer_ignore(const struct sctp_endpoint *ep, | |
5180 | const struct sctp_association *asoc, | |
5181 | const sctp_subtype_t type, | |
5182 | void *arg, | |
5183 | sctp_cmd_seq_t *commands) | |
5184 | { | |
5185 | SCTP_DEBUG_PRINTK("Timer %d ignored.\n", type.chunk); | |
5186 | return SCTP_DISPOSITION_CONSUME; | |
5187 | } | |
5188 | ||
5189 | /******************************************************************** | |
5190 | * 2nd Level Abstractions | |
5191 | ********************************************************************/ | |
5192 | ||
5193 | /* Pull the SACK chunk based on the SACK header. */ | |
5194 | static struct sctp_sackhdr *sctp_sm_pull_sack(struct sctp_chunk *chunk) | |
5195 | { | |
5196 | struct sctp_sackhdr *sack; | |
5197 | unsigned int len; | |
5198 | __u16 num_blocks; | |
5199 | __u16 num_dup_tsns; | |
5200 | ||
5201 | /* Protect ourselves from reading too far into | |
5202 | * the skb from a bogus sender. | |
5203 | */ | |
5204 | sack = (struct sctp_sackhdr *) chunk->skb->data; | |
5205 | ||
5206 | num_blocks = ntohs(sack->num_gap_ack_blocks); | |
5207 | num_dup_tsns = ntohs(sack->num_dup_tsns); | |
5208 | len = sizeof(struct sctp_sackhdr); | |
5209 | len += (num_blocks + num_dup_tsns) * sizeof(__u32); | |
5210 | if (len > chunk->skb->len) | |
5211 | return NULL; | |
5212 | ||
5213 | skb_pull(chunk->skb, len); | |
5214 | ||
5215 | return sack; | |
5216 | } | |
5217 | ||
5218 | /* Create an ABORT packet to be sent as a response, with the specified | |
5219 | * error causes. | |
5220 | */ | |
5221 | static struct sctp_packet *sctp_abort_pkt_new(const struct sctp_endpoint *ep, | |
5222 | const struct sctp_association *asoc, | |
5223 | struct sctp_chunk *chunk, | |
5224 | const void *payload, | |
5225 | size_t paylen) | |
5226 | { | |
5227 | struct sctp_packet *packet; | |
5228 | struct sctp_chunk *abort; | |
5229 | ||
5230 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5231 | ||
5232 | if (packet) { | |
5233 | /* Make an ABORT. | |
5234 | * The T bit will be set if the asoc is NULL. | |
5235 | */ | |
5236 | abort = sctp_make_abort(asoc, chunk, paylen); | |
5237 | if (!abort) { | |
5238 | sctp_ootb_pkt_free(packet); | |
5239 | return NULL; | |
5240 | } | |
047a2428 JF |
5241 | |
5242 | /* Reflect vtag if T-Bit is set */ | |
5243 | if (sctp_test_T_bit(abort)) | |
5244 | packet->vtag = ntohl(chunk->sctp_hdr->vtag); | |
5245 | ||
1da177e4 LT |
5246 | /* Add specified error causes, i.e., payload, to the |
5247 | * end of the chunk. | |
5248 | */ | |
5249 | sctp_addto_chunk(abort, paylen, payload); | |
5250 | ||
5251 | /* Set the skb to the belonging sock for accounting. */ | |
5252 | abort->skb->sk = ep->base.sk; | |
5253 | ||
5254 | sctp_packet_append_chunk(packet, abort); | |
5255 | ||
5256 | } | |
5257 | ||
5258 | return packet; | |
5259 | } | |
5260 | ||
5261 | /* Allocate a packet for responding in the OOTB conditions. */ | |
5262 | static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc, | |
5263 | const struct sctp_chunk *chunk) | |
5264 | { | |
5265 | struct sctp_packet *packet; | |
5266 | struct sctp_transport *transport; | |
5267 | __u16 sport; | |
5268 | __u16 dport; | |
5269 | __u32 vtag; | |
5270 | ||
5271 | /* Get the source and destination port from the inbound packet. */ | |
5272 | sport = ntohs(chunk->sctp_hdr->dest); | |
5273 | dport = ntohs(chunk->sctp_hdr->source); | |
5274 | ||
5275 | /* The V-tag is going to be the same as the inbound packet if no | |
5276 | * association exists, otherwise, use the peer's vtag. | |
5277 | */ | |
5278 | if (asoc) { | |
02c4e12c WY |
5279 | /* Special case the INIT-ACK as there is no peer's vtag |
5280 | * yet. | |
5281 | */ | |
5282 | switch(chunk->chunk_hdr->type) { | |
5283 | case SCTP_CID_INIT_ACK: | |
5284 | { | |
5285 | sctp_initack_chunk_t *initack; | |
5286 | ||
5287 | initack = (sctp_initack_chunk_t *)chunk->chunk_hdr; | |
5288 | vtag = ntohl(initack->init_hdr.init_tag); | |
5289 | break; | |
5290 | } | |
5291 | default: | |
5292 | vtag = asoc->peer.i.init_tag; | |
5293 | break; | |
5294 | } | |
1da177e4 LT |
5295 | } else { |
5296 | /* Special case the INIT and stale COOKIE_ECHO as there is no | |
5297 | * vtag yet. | |
5298 | */ | |
5299 | switch(chunk->chunk_hdr->type) { | |
5300 | case SCTP_CID_INIT: | |
5301 | { | |
5302 | sctp_init_chunk_t *init; | |
5303 | ||
5304 | init = (sctp_init_chunk_t *)chunk->chunk_hdr; | |
5305 | vtag = ntohl(init->init_hdr.init_tag); | |
5306 | break; | |
5307 | } | |
d808ad9a | 5308 | default: |
1da177e4 LT |
5309 | vtag = ntohl(chunk->sctp_hdr->vtag); |
5310 | break; | |
5311 | } | |
5312 | } | |
5313 | ||
5314 | /* Make a transport for the bucket, Eliza... */ | |
6a1e5f33 | 5315 | transport = sctp_transport_new(sctp_source(chunk), GFP_ATOMIC); |
1da177e4 LT |
5316 | if (!transport) |
5317 | goto nomem; | |
5318 | ||
5319 | /* Cache a route for the transport with the chunk's destination as | |
5320 | * the source address. | |
5321 | */ | |
16b0a030 | 5322 | sctp_transport_route(transport, (union sctp_addr *)&chunk->dest, |
1da177e4 LT |
5323 | sctp_sk(sctp_get_ctl_sock())); |
5324 | ||
5325 | packet = sctp_packet_init(&transport->packet, transport, sport, dport); | |
5326 | packet = sctp_packet_config(packet, vtag, 0); | |
5327 | ||
5328 | return packet; | |
5329 | ||
5330 | nomem: | |
5331 | return NULL; | |
5332 | } | |
5333 | ||
5334 | /* Free the packet allocated earlier for responding in the OOTB condition. */ | |
5335 | void sctp_ootb_pkt_free(struct sctp_packet *packet) | |
5336 | { | |
5337 | sctp_transport_free(packet->transport); | |
5338 | } | |
5339 | ||
5340 | /* Send a stale cookie error when a invalid COOKIE ECHO chunk is found */ | |
5341 | static void sctp_send_stale_cookie_err(const struct sctp_endpoint *ep, | |
5342 | const struct sctp_association *asoc, | |
5343 | const struct sctp_chunk *chunk, | |
5344 | sctp_cmd_seq_t *commands, | |
5345 | struct sctp_chunk *err_chunk) | |
5346 | { | |
5347 | struct sctp_packet *packet; | |
5348 | ||
5349 | if (err_chunk) { | |
5350 | packet = sctp_ootb_pkt_new(asoc, chunk); | |
5351 | if (packet) { | |
5352 | struct sctp_signed_cookie *cookie; | |
5353 | ||
5354 | /* Override the OOTB vtag from the cookie. */ | |
5355 | cookie = chunk->subh.cookie_hdr; | |
5356 | packet->vtag = cookie->c.peer_vtag; | |
d808ad9a | 5357 | |
1da177e4 LT |
5358 | /* Set the skb to the belonging sock for accounting. */ |
5359 | err_chunk->skb->sk = ep->base.sk; | |
5360 | sctp_packet_append_chunk(packet, err_chunk); | |
5361 | sctp_add_cmd_sf(commands, SCTP_CMD_SEND_PKT, | |
5362 | SCTP_PACKET(packet)); | |
5363 | SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); | |
5364 | } else | |
5365 | sctp_chunk_free (err_chunk); | |
5366 | } | |
5367 | } | |
5368 | ||
5369 | ||
5370 | /* Process a data chunk */ | |
5371 | static int sctp_eat_data(const struct sctp_association *asoc, | |
5372 | struct sctp_chunk *chunk, | |
5373 | sctp_cmd_seq_t *commands) | |
5374 | { | |
5375 | sctp_datahdr_t *data_hdr; | |
5376 | struct sctp_chunk *err; | |
5377 | size_t datalen; | |
5378 | sctp_verb_t deliver; | |
5379 | int tmp; | |
5380 | __u32 tsn; | |
049b3ff5 | 5381 | int account_value; |
7c3ceb4f | 5382 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
049b3ff5 | 5383 | struct sock *sk = asoc->base.sk; |
7c3ceb4f | 5384 | int rcvbuf_over = 0; |
1da177e4 LT |
5385 | |
5386 | data_hdr = chunk->subh.data_hdr = (sctp_datahdr_t *)chunk->skb->data; | |
5387 | skb_pull(chunk->skb, sizeof(sctp_datahdr_t)); | |
5388 | ||
5389 | tsn = ntohl(data_hdr->tsn); | |
5390 | SCTP_DEBUG_PRINTK("eat_data: TSN 0x%x.\n", tsn); | |
5391 | ||
5392 | /* ASSERT: Now skb->data is really the user data. */ | |
5393 | ||
049b3ff5 | 5394 | /* |
7c3ceb4f NH |
5395 | * If we are established, and we have used up our receive buffer |
5396 | * memory, think about droping the frame. | |
5397 | * Note that we have an opportunity to improve performance here. | |
5398 | * If we accept one chunk from an skbuff, we have to keep all the | |
5399 | * memory of that skbuff around until the chunk is read into user | |
5400 | * space. Therefore, once we accept 1 chunk we may as well accept all | |
5401 | * remaining chunks in the skbuff. The data_accepted flag helps us do | |
5402 | * that. | |
5403 | */ | |
5404 | if ((asoc->state == SCTP_STATE_ESTABLISHED) && (!chunk->data_accepted)) { | |
049b3ff5 NH |
5405 | /* |
5406 | * If the receive buffer policy is 1, then each | |
5407 | * association can allocate up to sk_rcvbuf bytes | |
5408 | * otherwise, all the associations in aggregate | |
5409 | * may allocate up to sk_rcvbuf bytes | |
5410 | */ | |
5411 | if (asoc->ep->rcvbuf_policy) | |
5412 | account_value = atomic_read(&asoc->rmem_alloc); | |
5413 | else | |
5414 | account_value = atomic_read(&sk->sk_rmem_alloc); | |
7c3ceb4f NH |
5415 | if (account_value > sk->sk_rcvbuf) { |
5416 | /* | |
5417 | * We need to make forward progress, even when we are | |
5418 | * under memory pressure, so we always allow the | |
5419 | * next tsn after the ctsn ack point to be accepted. | |
5420 | * This lets us avoid deadlocks in which we have to | |
5421 | * drop frames that would otherwise let us drain the | |
5422 | * receive queue. | |
5423 | */ | |
5424 | if ((sctp_tsnmap_get_ctsn(map) + 1) != tsn) | |
5425 | return SCTP_IERROR_IGNORE_TSN; | |
5426 | ||
5427 | /* | |
5428 | * We're going to accept the frame but we should renege | |
5429 | * to make space for it. This will send us down that | |
5430 | * path later in this function. | |
5431 | */ | |
5432 | rcvbuf_over = 1; | |
5433 | } | |
049b3ff5 NH |
5434 | } |
5435 | ||
1da177e4 LT |
5436 | /* Process ECN based congestion. |
5437 | * | |
5438 | * Since the chunk structure is reused for all chunks within | |
5439 | * a packet, we use ecn_ce_done to track if we've already | |
5440 | * done CE processing for this packet. | |
5441 | * | |
5442 | * We need to do ECN processing even if we plan to discard the | |
5443 | * chunk later. | |
5444 | */ | |
5445 | ||
5446 | if (!chunk->ecn_ce_done) { | |
5447 | struct sctp_af *af; | |
5448 | chunk->ecn_ce_done = 1; | |
5449 | ||
5450 | af = sctp_get_af_specific( | |
eddc9ec5 | 5451 | ipver2af(ip_hdr(chunk->skb)->version)); |
1da177e4 LT |
5452 | |
5453 | if (af && af->is_ce(chunk->skb) && asoc->peer.ecn_capable) { | |
5454 | /* Do real work as sideffect. */ | |
5455 | sctp_add_cmd_sf(commands, SCTP_CMD_ECN_CE, | |
5456 | SCTP_U32(tsn)); | |
5457 | } | |
5458 | } | |
5459 | ||
5460 | tmp = sctp_tsnmap_check(&asoc->peer.tsn_map, tsn); | |
5461 | if (tmp < 0) { | |
5462 | /* The TSN is too high--silently discard the chunk and | |
5463 | * count on it getting retransmitted later. | |
5464 | */ | |
5465 | return SCTP_IERROR_HIGH_TSN; | |
5466 | } else if (tmp > 0) { | |
5467 | /* This is a duplicate. Record it. */ | |
5468 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_DUP, SCTP_U32(tsn)); | |
5469 | return SCTP_IERROR_DUP_TSN; | |
5470 | } | |
5471 | ||
5472 | /* This is a new TSN. */ | |
5473 | ||
5474 | /* Discard if there is no room in the receive window. | |
5475 | * Actually, allow a little bit of overflow (up to a MTU). | |
5476 | */ | |
5477 | datalen = ntohs(chunk->chunk_hdr->length); | |
5478 | datalen -= sizeof(sctp_data_chunk_t); | |
5479 | ||
5480 | deliver = SCTP_CMD_CHUNK_ULP; | |
5481 | ||
5482 | /* Think about partial delivery. */ | |
5483 | if ((datalen >= asoc->rwnd) && (!asoc->ulpq.pd_mode)) { | |
5484 | ||
5485 | /* Even if we don't accept this chunk there is | |
5486 | * memory pressure. | |
5487 | */ | |
5488 | sctp_add_cmd_sf(commands, SCTP_CMD_PART_DELIVER, SCTP_NULL()); | |
5489 | } | |
5490 | ||
d808ad9a | 5491 | /* Spill over rwnd a little bit. Note: While allowed, this spill over |
1da177e4 LT |
5492 | * seems a bit troublesome in that frag_point varies based on |
5493 | * PMTU. In cases, such as loopback, this might be a rather | |
5494 | * large spill over. | |
d5b9f4c0 NH |
5495 | * NOTE: If we have a full receive buffer here, we only renege if |
5496 | * our receiver can still make progress without the tsn being | |
5497 | * received. We do this because in the event that the associations | |
5498 | * receive queue is empty we are filling a leading gap, and since | |
5499 | * reneging moves the gap to the end of the tsn stream, we are likely | |
5500 | * to stall again very shortly. Avoiding the renege when we fill a | |
5501 | * leading gap is a good heuristic for avoiding such steady state | |
5502 | * stalls. | |
1da177e4 LT |
5503 | */ |
5504 | if (!asoc->rwnd || asoc->rwnd_over || | |
7c3ceb4f | 5505 | (datalen > asoc->rwnd + asoc->frag_point) || |
d5b9f4c0 | 5506 | (rcvbuf_over && (!skb_queue_len(&sk->sk_receive_queue)))) { |
1da177e4 LT |
5507 | |
5508 | /* If this is the next TSN, consider reneging to make | |
5509 | * room. Note: Playing nice with a confused sender. A | |
5510 | * malicious sender can still eat up all our buffer | |
5511 | * space and in the future we may want to detect and | |
5512 | * do more drastic reneging. | |
5513 | */ | |
7c3ceb4f NH |
5514 | if (sctp_tsnmap_has_gap(map) && |
5515 | (sctp_tsnmap_get_ctsn(map) + 1) == tsn) { | |
1da177e4 LT |
5516 | SCTP_DEBUG_PRINTK("Reneging for tsn:%u\n", tsn); |
5517 | deliver = SCTP_CMD_RENEGE; | |
5518 | } else { | |
5519 | SCTP_DEBUG_PRINTK("Discard tsn: %u len: %Zd, " | |
5520 | "rwnd: %d\n", tsn, datalen, | |
5521 | asoc->rwnd); | |
5522 | return SCTP_IERROR_IGNORE_TSN; | |
5523 | } | |
5524 | } | |
5525 | ||
5526 | /* | |
5527 | * Section 3.3.10.9 No User Data (9) | |
5528 | * | |
5529 | * Cause of error | |
5530 | * --------------- | |
5531 | * No User Data: This error cause is returned to the originator of a | |
5532 | * DATA chunk if a received DATA chunk has no user data. | |
5533 | */ | |
5534 | if (unlikely(0 == datalen)) { | |
5535 | err = sctp_make_abort_no_data(asoc, chunk, tsn); | |
5536 | if (err) { | |
5537 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5538 | SCTP_CHUNK(err)); | |
5539 | } | |
5540 | /* We are going to ABORT, so we might as well stop | |
5541 | * processing the rest of the chunks in the packet. | |
5542 | */ | |
5543 | sctp_add_cmd_sf(commands, SCTP_CMD_DISCARD_PACKET,SCTP_NULL()); | |
8de8c873 SS |
5544 | sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, |
5545 | SCTP_ERROR(ECONNABORTED)); | |
1da177e4 | 5546 | sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, |
5be291fe | 5547 | SCTP_PERR(SCTP_ERROR_NO_DATA)); |
1da177e4 LT |
5548 | SCTP_INC_STATS(SCTP_MIB_ABORTEDS); |
5549 | SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); | |
5550 | return SCTP_IERROR_NO_DATA; | |
5551 | } | |
5552 | ||
5553 | /* If definately accepting the DATA chunk, record its TSN, otherwise | |
5554 | * wait for renege processing. | |
5555 | */ | |
5556 | if (SCTP_CMD_CHUNK_ULP == deliver) | |
5557 | sctp_add_cmd_sf(commands, SCTP_CMD_REPORT_TSN, SCTP_U32(tsn)); | |
5558 | ||
9faa730f SS |
5559 | chunk->data_accepted = 1; |
5560 | ||
1da177e4 LT |
5561 | /* Note: Some chunks may get overcounted (if we drop) or overcounted |
5562 | * if we renege and the chunk arrives again. | |
5563 | */ | |
5564 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) | |
5565 | SCTP_INC_STATS(SCTP_MIB_INUNORDERCHUNKS); | |
5566 | else | |
5567 | SCTP_INC_STATS(SCTP_MIB_INORDERCHUNKS); | |
5568 | ||
5569 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number | |
5570 | * | |
5571 | * If an endpoint receive a DATA chunk with an invalid stream | |
5572 | * identifier, it shall acknowledge the reception of the DATA chunk | |
5573 | * following the normal procedure, immediately send an ERROR chunk | |
5574 | * with cause set to "Invalid Stream Identifier" (See Section 3.3.10) | |
5575 | * and discard the DATA chunk. | |
5576 | */ | |
5577 | if (ntohs(data_hdr->stream) >= asoc->c.sinit_max_instreams) { | |
5578 | err = sctp_make_op_error(asoc, chunk, SCTP_ERROR_INV_STRM, | |
5579 | &data_hdr->stream, | |
5580 | sizeof(data_hdr->stream)); | |
5581 | if (err) | |
5582 | sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, | |
5583 | SCTP_CHUNK(err)); | |
5584 | return SCTP_IERROR_BAD_STREAM; | |
5585 | } | |
5586 | ||
5587 | /* Send the data up to the user. Note: Schedule the | |
5588 | * SCTP_CMD_CHUNK_ULP cmd before the SCTP_CMD_GEN_SACK, as the SACK | |
5589 | * chunk needs the updated rwnd. | |
5590 | */ | |
5591 | sctp_add_cmd_sf(commands, deliver, SCTP_CHUNK(chunk)); | |
5592 | ||
5593 | return SCTP_IERROR_NO_ERROR; | |
5594 | } |