1 /* SCTP kernel reference Implementation 2 * (C) Copyright IBM Corp. 2001, 2004 3 * Copyright (c) 1999 Cisco, Inc. 4 * Copyright (c) 1999-2001 Motorola, Inc. 5 * 6 * This file is part of the SCTP kernel reference Implementation 7 * 8 * These functions work with the state functions in sctp_sm_statefuns.c 9 * to implement that state operations. These functions implement the 10 * steps which require modifying existing data structures. 11 * 12 * The SCTP reference implementation is free software; 13 * you can redistribute it and/or modify it under the terms of 14 * the GNU General Public License as published by 15 * the Free Software Foundation; either version 2, or (at your option) 16 * any later version. 17 * 18 * The SCTP reference implementation is distributed in the hope that it 19 * will be useful, but WITHOUT ANY WARRANTY; without even the implied 20 * ************************ 21 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 22 * See the GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with GNU CC; see the file COPYING. If not, write to 26 * the Free Software Foundation, 59 Temple Place - Suite 330, 27 * Boston, MA 02111-1307, USA. 28 * 29 * Please send any bug reports or fixes you make to the 30 * email address(es): 31 * lksctp developers <lksctp-developers@lists.sourceforge.net> 32 * 33 * Or submit a bug report through the following website: 34 * http://www.sf.net/projects/lksctp 35 * 36 * Written or modified by: 37 * La Monte H.P. Yarroll <piggy@acm.org> 38 * Karl Knutson <karl@athena.chicago.il.us> 39 * Jon Grimm <jgrimm@austin.ibm.com> 40 * Hui Huang <hui.huang@nokia.com> 41 * Dajiang Zhang <dajiang.zhang@nokia.com> 42 * Daisy Chang <daisyc@us.ibm.com> 43 * Sridhar Samudrala <sri@us.ibm.com> 44 * Ardelle Fan <ardelle.fan@intel.com> 45 * 46 * Any bugs reported given to us we will try to fix... any fixes shared will 47 * be incorporated into the next SCTP release. 48 */ 49 50 #include <linux/skbuff.h> 51 #include <linux/types.h> 52 #include <linux/socket.h> 53 #include <linux/ip.h> 54 #include <net/sock.h> 55 #include <net/sctp/sctp.h> 56 #include <net/sctp/sm.h> 57 58 static int sctp_cmd_interpreter(sctp_event_t event_type, 59 sctp_subtype_t subtype, 60 sctp_state_t state, 61 struct sctp_endpoint *ep, 62 struct sctp_association *asoc, 63 void *event_arg, 64 sctp_disposition_t status, 65 sctp_cmd_seq_t *commands, 66 gfp_t gfp); 67 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 68 sctp_state_t state, 69 struct sctp_endpoint *ep, 70 struct sctp_association *asoc, 71 void *event_arg, 72 sctp_disposition_t status, 73 sctp_cmd_seq_t *commands, 74 gfp_t gfp); 75 76 /******************************************************************** 77 * Helper functions 78 ********************************************************************/ 79 80 /* A helper function for delayed processing of INET ECN CE bit. */ 81 static void sctp_do_ecn_ce_work(struct sctp_association *asoc, 82 __u32 lowest_tsn) 83 { 84 /* Save the TSN away for comparison when we receive CWR */ 85 86 asoc->last_ecne_tsn = lowest_tsn; 87 asoc->need_ecne = 1; 88 } 89 90 /* Helper function for delayed processing of SCTP ECNE chunk. */ 91 /* RFC 2960 Appendix A 92 * 93 * RFC 2481 details a specific bit for a sender to send in 94 * the header of its next outbound TCP segment to indicate to 95 * its peer that it has reduced its congestion window. This 96 * is termed the CWR bit. For SCTP the same indication is made 97 * by including the CWR chunk. This chunk contains one data 98 * element, i.e. the TSN number that was sent in the ECNE chunk. 99 * This element represents the lowest TSN number in the datagram 100 * that was originally marked with the CE bit. 101 */ 102 static struct sctp_chunk *sctp_do_ecn_ecne_work(struct sctp_association *asoc, 103 __u32 lowest_tsn, 104 struct sctp_chunk *chunk) 105 { 106 struct sctp_chunk *repl; 107 108 /* Our previously transmitted packet ran into some congestion 109 * so we should take action by reducing cwnd and ssthresh 110 * and then ACK our peer that we we've done so by 111 * sending a CWR. 112 */ 113 114 /* First, try to determine if we want to actually lower 115 * our cwnd variables. Only lower them if the ECNE looks more 116 * recent than the last response. 117 */ 118 if (TSN_lt(asoc->last_cwr_tsn, lowest_tsn)) { 119 struct sctp_transport *transport; 120 121 /* Find which transport's congestion variables 122 * need to be adjusted. 123 */ 124 transport = sctp_assoc_lookup_tsn(asoc, lowest_tsn); 125 126 /* Update the congestion variables. */ 127 if (transport) 128 sctp_transport_lower_cwnd(transport, 129 SCTP_LOWER_CWND_ECNE); 130 asoc->last_cwr_tsn = lowest_tsn; 131 } 132 133 /* Always try to quiet the other end. In case of lost CWR, 134 * resend last_cwr_tsn. 135 */ 136 repl = sctp_make_cwr(asoc, asoc->last_cwr_tsn, chunk); 137 138 /* If we run out of memory, it will look like a lost CWR. We'll 139 * get back in sync eventually. 140 */ 141 return repl; 142 } 143 144 /* Helper function to do delayed processing of ECN CWR chunk. */ 145 static void sctp_do_ecn_cwr_work(struct sctp_association *asoc, 146 __u32 lowest_tsn) 147 { 148 /* Turn off ECNE getting auto-prepended to every outgoing 149 * packet 150 */ 151 asoc->need_ecne = 0; 152 } 153 154 /* Generate SACK if necessary. We call this at the end of a packet. */ 155 static int sctp_gen_sack(struct sctp_association *asoc, int force, 156 sctp_cmd_seq_t *commands) 157 { 158 __u32 ctsn, max_tsn_seen; 159 struct sctp_chunk *sack; 160 struct sctp_transport *trans = asoc->peer.last_data_from; 161 int error = 0; 162 163 if (force || 164 (!trans && (asoc->param_flags & SPP_SACKDELAY_DISABLE)) || 165 (trans && (trans->param_flags & SPP_SACKDELAY_DISABLE))) 166 asoc->peer.sack_needed = 1; 167 168 ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); 169 max_tsn_seen = sctp_tsnmap_get_max_tsn_seen(&asoc->peer.tsn_map); 170 171 /* From 12.2 Parameters necessary per association (i.e. the TCB): 172 * 173 * Ack State : This flag indicates if the next received packet 174 * : is to be responded to with a SACK. ... 175 * : When DATA chunks are out of order, SACK's 176 * : are not delayed (see Section 6). 177 * 178 * [This is actually not mentioned in Section 6, but we 179 * implement it here anyway. --piggy] 180 */ 181 if (max_tsn_seen != ctsn) 182 asoc->peer.sack_needed = 1; 183 184 /* From 6.2 Acknowledgement on Reception of DATA Chunks: 185 * 186 * Section 4.2 of [RFC2581] SHOULD be followed. Specifically, 187 * an acknowledgement SHOULD be generated for at least every 188 * second packet (not every second DATA chunk) received, and 189 * SHOULD be generated within 200 ms of the arrival of any 190 * unacknowledged DATA chunk. ... 191 */ 192 if (!asoc->peer.sack_needed) { 193 /* We will need a SACK for the next packet. */ 194 asoc->peer.sack_needed = 1; 195 196 /* Set the SACK delay timeout based on the 197 * SACK delay for the last transport 198 * data was received from, or the default 199 * for the association. 200 */ 201 if (trans) 202 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 203 trans->sackdelay; 204 else 205 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 206 asoc->sackdelay; 207 208 /* Restart the SACK timer. */ 209 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 210 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 211 } else { 212 if (asoc->a_rwnd > asoc->rwnd) 213 asoc->a_rwnd = asoc->rwnd; 214 sack = sctp_make_sack(asoc); 215 if (!sack) 216 goto nomem; 217 218 asoc->peer.sack_needed = 0; 219 220 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack)); 221 222 /* Stop the SACK timer. */ 223 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, 224 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 225 } 226 227 return error; 228 nomem: 229 error = -ENOMEM; 230 return error; 231 } 232 233 /* When the T3-RTX timer expires, it calls this function to create the 234 * relevant state machine event. 235 */ 236 void sctp_generate_t3_rtx_event(unsigned long peer) 237 { 238 int error; 239 struct sctp_transport *transport = (struct sctp_transport *) peer; 240 struct sctp_association *asoc = transport->asoc; 241 242 /* Check whether a task is in the sock. */ 243 244 sctp_bh_lock_sock(asoc->base.sk); 245 if (sock_owned_by_user(asoc->base.sk)) { 246 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__); 247 248 /* Try again later. */ 249 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20))) 250 sctp_transport_hold(transport); 251 goto out_unlock; 252 } 253 254 /* Is this transport really dead and just waiting around for 255 * the timer to let go of the reference? 256 */ 257 if (transport->dead) 258 goto out_unlock; 259 260 /* Run through the state machine. */ 261 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 262 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX), 263 asoc->state, 264 asoc->ep, asoc, 265 transport, GFP_ATOMIC); 266 267 if (error) 268 asoc->base.sk->sk_err = -error; 269 270 out_unlock: 271 sctp_bh_unlock_sock(asoc->base.sk); 272 sctp_transport_put(transport); 273 } 274 275 /* This is a sa interface for producing timeout events. It works 276 * for timeouts which use the association as their parameter. 277 */ 278 static void sctp_generate_timeout_event(struct sctp_association *asoc, 279 sctp_event_timeout_t timeout_type) 280 { 281 int error = 0; 282 283 sctp_bh_lock_sock(asoc->base.sk); 284 if (sock_owned_by_user(asoc->base.sk)) { 285 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n", 286 __FUNCTION__, 287 timeout_type); 288 289 /* Try again later. */ 290 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20))) 291 sctp_association_hold(asoc); 292 goto out_unlock; 293 } 294 295 /* Is this association really dead and just waiting around for 296 * the timer to let go of the reference? 297 */ 298 if (asoc->base.dead) 299 goto out_unlock; 300 301 /* Run through the state machine. */ 302 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 303 SCTP_ST_TIMEOUT(timeout_type), 304 asoc->state, asoc->ep, asoc, 305 (void *)timeout_type, GFP_ATOMIC); 306 307 if (error) 308 asoc->base.sk->sk_err = -error; 309 310 out_unlock: 311 sctp_bh_unlock_sock(asoc->base.sk); 312 sctp_association_put(asoc); 313 } 314 315 static void sctp_generate_t1_cookie_event(unsigned long data) 316 { 317 struct sctp_association *asoc = (struct sctp_association *) data; 318 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE); 319 } 320 321 static void sctp_generate_t1_init_event(unsigned long data) 322 { 323 struct sctp_association *asoc = (struct sctp_association *) data; 324 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT); 325 } 326 327 static void sctp_generate_t2_shutdown_event(unsigned long data) 328 { 329 struct sctp_association *asoc = (struct sctp_association *) data; 330 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN); 331 } 332 333 static void sctp_generate_t4_rto_event(unsigned long data) 334 { 335 struct sctp_association *asoc = (struct sctp_association *) data; 336 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO); 337 } 338 339 static void sctp_generate_t5_shutdown_guard_event(unsigned long data) 340 { 341 struct sctp_association *asoc = (struct sctp_association *)data; 342 sctp_generate_timeout_event(asoc, 343 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD); 344 345 } /* sctp_generate_t5_shutdown_guard_event() */ 346 347 static void sctp_generate_autoclose_event(unsigned long data) 348 { 349 struct sctp_association *asoc = (struct sctp_association *) data; 350 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE); 351 } 352 353 /* Generate a heart beat event. If the sock is busy, reschedule. Make 354 * sure that the transport is still valid. 355 */ 356 void sctp_generate_heartbeat_event(unsigned long data) 357 { 358 int error = 0; 359 struct sctp_transport *transport = (struct sctp_transport *) data; 360 struct sctp_association *asoc = transport->asoc; 361 362 sctp_bh_lock_sock(asoc->base.sk); 363 if (sock_owned_by_user(asoc->base.sk)) { 364 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __FUNCTION__); 365 366 /* Try again later. */ 367 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20))) 368 sctp_transport_hold(transport); 369 goto out_unlock; 370 } 371 372 /* Is this structure just waiting around for us to actually 373 * get destroyed? 374 */ 375 if (transport->dead) 376 goto out_unlock; 377 378 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 379 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT), 380 asoc->state, asoc->ep, asoc, 381 transport, GFP_ATOMIC); 382 383 if (error) 384 asoc->base.sk->sk_err = -error; 385 386 out_unlock: 387 sctp_bh_unlock_sock(asoc->base.sk); 388 sctp_transport_put(transport); 389 } 390 391 /* Inject a SACK Timeout event into the state machine. */ 392 static void sctp_generate_sack_event(unsigned long data) 393 { 394 struct sctp_association *asoc = (struct sctp_association *) data; 395 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK); 396 } 397 398 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = { 399 NULL, 400 sctp_generate_t1_cookie_event, 401 sctp_generate_t1_init_event, 402 sctp_generate_t2_shutdown_event, 403 NULL, 404 sctp_generate_t4_rto_event, 405 sctp_generate_t5_shutdown_guard_event, 406 NULL, 407 sctp_generate_sack_event, 408 sctp_generate_autoclose_event, 409 }; 410 411 412 /* RFC 2960 8.2 Path Failure Detection 413 * 414 * When its peer endpoint is multi-homed, an endpoint should keep a 415 * error counter for each of the destination transport addresses of the 416 * peer endpoint. 417 * 418 * Each time the T3-rtx timer expires on any address, or when a 419 * HEARTBEAT sent to an idle address is not acknowledged within a RTO, 420 * the error counter of that destination address will be incremented. 421 * When the value in the error counter exceeds the protocol parameter 422 * 'Path.Max.Retrans' of that destination address, the endpoint should 423 * mark the destination transport address as inactive, and a 424 * notification SHOULD be sent to the upper layer. 425 * 426 */ 427 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc, 428 struct sctp_transport *transport) 429 { 430 /* The check for association's overall error counter exceeding the 431 * threshold is done in the state function. 432 */ 433 /* When probing UNCONFIRMED addresses, the association overall 434 * error count is NOT incremented 435 */ 436 if (transport->state != SCTP_UNCONFIRMED) 437 asoc->overall_error_count++; 438 439 if (transport->state != SCTP_INACTIVE && 440 (transport->error_count++ >= transport->pathmaxrxt)) { 441 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", 442 " transport IP: port:%d failed.\n", 443 asoc, 444 (&transport->ipaddr), 445 ntohs(transport->ipaddr.v4.sin_port)); 446 sctp_assoc_control_transport(asoc, transport, 447 SCTP_TRANSPORT_DOWN, 448 SCTP_FAILED_THRESHOLD); 449 } 450 451 /* E2) For the destination address for which the timer 452 * expires, set RTO <- RTO * 2 ("back off the timer"). The 453 * maximum value discussed in rule C7 above (RTO.max) may be 454 * used to provide an upper bound to this doubling operation. 455 */ 456 transport->rto = min((transport->rto * 2), transport->asoc->rto_max); 457 } 458 459 /* Worker routine to handle INIT command failure. */ 460 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, 461 struct sctp_association *asoc, 462 unsigned error) 463 { 464 struct sctp_ulpevent *event; 465 466 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC, 467 (__u16)error, 0, 0, NULL, 468 GFP_ATOMIC); 469 470 if (event) 471 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 472 SCTP_ULPEVENT(event)); 473 474 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 475 SCTP_STATE(SCTP_STATE_CLOSED)); 476 477 /* SEND_FAILED sent later when cleaning up the association. */ 478 asoc->outqueue.error = error; 479 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 480 } 481 482 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ 483 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, 484 struct sctp_association *asoc, 485 sctp_event_t event_type, 486 sctp_subtype_t subtype, 487 struct sctp_chunk *chunk, 488 unsigned error) 489 { 490 struct sctp_ulpevent *event; 491 492 /* Cancel any partial delivery in progress. */ 493 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 494 495 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT) 496 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 497 (__u16)error, 0, 0, chunk, 498 GFP_ATOMIC); 499 else 500 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 501 (__u16)error, 0, 0, NULL, 502 GFP_ATOMIC); 503 if (event) 504 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 505 SCTP_ULPEVENT(event)); 506 507 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 508 SCTP_STATE(SCTP_STATE_CLOSED)); 509 510 /* SEND_FAILED sent later when cleaning up the association. */ 511 asoc->outqueue.error = error; 512 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 513 } 514 515 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT 516 * inside the cookie. In reality, this is only used for INIT-ACK processing 517 * since all other cases use "temporary" associations and can do all 518 * their work in statefuns directly. 519 */ 520 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, 521 struct sctp_association *asoc, 522 struct sctp_chunk *chunk, 523 sctp_init_chunk_t *peer_init, 524 gfp_t gfp) 525 { 526 int error; 527 528 /* We only process the init as a sideeffect in a single 529 * case. This is when we process the INIT-ACK. If we 530 * fail during INIT processing (due to malloc problems), 531 * just return the error and stop processing the stack. 532 */ 533 if (!sctp_process_init(asoc, chunk->chunk_hdr->type, 534 sctp_source(chunk), peer_init, gfp)) 535 error = -ENOMEM; 536 else 537 error = 0; 538 539 return error; 540 } 541 542 /* Helper function to break out starting up of heartbeat timers. */ 543 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, 544 struct sctp_association *asoc) 545 { 546 struct sctp_transport *t; 547 struct list_head *pos; 548 549 /* Start a heartbeat timer for each transport on the association. 550 * hold a reference on the transport to make sure none of 551 * the needed data structures go away. 552 */ 553 list_for_each(pos, &asoc->peer.transport_addr_list) { 554 t = list_entry(pos, struct sctp_transport, transports); 555 556 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 557 sctp_transport_hold(t); 558 } 559 } 560 561 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, 562 struct sctp_association *asoc) 563 { 564 struct sctp_transport *t; 565 struct list_head *pos; 566 567 /* Stop all heartbeat timers. */ 568 569 list_for_each(pos, &asoc->peer.transport_addr_list) { 570 t = list_entry(pos, struct sctp_transport, transports); 571 if (del_timer(&t->hb_timer)) 572 sctp_transport_put(t); 573 } 574 } 575 576 /* Helper function to stop any pending T3-RTX timers */ 577 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, 578 struct sctp_association *asoc) 579 { 580 struct sctp_transport *t; 581 struct list_head *pos; 582 583 list_for_each(pos, &asoc->peer.transport_addr_list) { 584 t = list_entry(pos, struct sctp_transport, transports); 585 if (timer_pending(&t->T3_rtx_timer) && 586 del_timer(&t->T3_rtx_timer)) { 587 sctp_transport_put(t); 588 } 589 } 590 } 591 592 593 /* Helper function to update the heartbeat timer. */ 594 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, 595 struct sctp_association *asoc, 596 struct sctp_transport *t) 597 { 598 /* Update the heartbeat timer. */ 599 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 600 sctp_transport_hold(t); 601 } 602 603 /* Helper function to handle the reception of an HEARTBEAT ACK. */ 604 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, 605 struct sctp_association *asoc, 606 struct sctp_transport *t, 607 struct sctp_chunk *chunk) 608 { 609 sctp_sender_hb_info_t *hbinfo; 610 611 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the 612 * HEARTBEAT should clear the error counter of the destination 613 * transport address to which the HEARTBEAT was sent. 614 * The association's overall error count is also cleared. 615 */ 616 t->error_count = 0; 617 t->asoc->overall_error_count = 0; 618 619 /* Mark the destination transport address as active if it is not so 620 * marked. 621 */ 622 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) 623 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, 624 SCTP_HEARTBEAT_SUCCESS); 625 626 /* The receiver of the HEARTBEAT ACK should also perform an 627 * RTT measurement for that destination transport address 628 * using the time value carried in the HEARTBEAT ACK chunk. 629 * If the transport's rto_pending variable has been cleared, 630 * it was most likely due to a retransmit. However, we want 631 * to re-enable it to properly update the rto. 632 */ 633 if (t->rto_pending == 0) 634 t->rto_pending = 1; 635 636 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; 637 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); 638 639 /* Update the heartbeat timer. */ 640 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 641 sctp_transport_hold(t); 642 } 643 644 /* Helper function to do a transport reset at the expiry of the hearbeat 645 * timer. 646 */ 647 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds, 648 struct sctp_association *asoc, 649 struct sctp_transport *t) 650 { 651 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); 652 653 /* Mark one strike against a transport. */ 654 sctp_do_8_2_transport_strike(asoc, t); 655 } 656 657 /* Helper function to process the process SACK command. */ 658 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, 659 struct sctp_association *asoc, 660 struct sctp_sackhdr *sackh) 661 { 662 int err; 663 664 if (sctp_outq_sack(&asoc->outqueue, sackh)) { 665 /* There are no more TSNs awaiting SACK. */ 666 err = sctp_do_sm(SCTP_EVENT_T_OTHER, 667 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), 668 asoc->state, asoc->ep, asoc, NULL, 669 GFP_ATOMIC); 670 } else { 671 /* Windows may have opened, so we need 672 * to check if we have DATA to transmit 673 */ 674 err = sctp_outq_flush(&asoc->outqueue, 0); 675 } 676 677 return err; 678 } 679 680 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set 681 * the transport for a shutdown chunk. 682 */ 683 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, 684 struct sctp_association *asoc, 685 struct sctp_chunk *chunk) 686 { 687 struct sctp_transport *t; 688 689 t = sctp_assoc_choose_shutdown_transport(asoc); 690 asoc->shutdown_last_sent_to = t; 691 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; 692 chunk->transport = t; 693 } 694 695 /* Helper function to change the state of an association. */ 696 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 697 struct sctp_association *asoc, 698 sctp_state_t state) 699 { 700 struct sock *sk = asoc->base.sk; 701 702 asoc->state = state; 703 704 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", 705 asoc, sctp_state_tbl[state]); 706 707 if (sctp_style(sk, TCP)) { 708 /* Change the sk->sk_state of a TCP-style socket that has 709 * sucessfully completed a connect() call. 710 */ 711 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) 712 sk->sk_state = SCTP_SS_ESTABLISHED; 713 714 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ 715 if (sctp_state(asoc, SHUTDOWN_RECEIVED) && 716 sctp_sstate(sk, ESTABLISHED)) 717 sk->sk_shutdown |= RCV_SHUTDOWN; 718 } 719 720 if (sctp_state(asoc, COOKIE_WAIT)) { 721 /* Reset init timeouts since they may have been 722 * increased due to timer expirations. 723 */ 724 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 725 asoc->rto_initial; 726 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 727 asoc->rto_initial; 728 } 729 730 if (sctp_state(asoc, ESTABLISHED) || 731 sctp_state(asoc, CLOSED) || 732 sctp_state(asoc, SHUTDOWN_RECEIVED)) { 733 /* Wake up any processes waiting in the asoc's wait queue in 734 * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). 735 */ 736 if (waitqueue_active(&asoc->wait)) 737 wake_up_interruptible(&asoc->wait); 738 739 /* Wake up any processes waiting in the sk's sleep queue of 740 * a TCP-style or UDP-style peeled-off socket in 741 * sctp_wait_for_accept() or sctp_wait_for_packet(). 742 * For a UDP-style socket, the waiters are woken up by the 743 * notifications. 744 */ 745 if (!sctp_style(sk, UDP)) 746 sk->sk_state_change(sk); 747 } 748 } 749 750 /* Helper function to delete an association. */ 751 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, 752 struct sctp_association *asoc) 753 { 754 struct sock *sk = asoc->base.sk; 755 756 /* If it is a non-temporary association belonging to a TCP-style 757 * listening socket that is not closed, do not free it so that accept() 758 * can pick it up later. 759 */ 760 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && 761 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) 762 return; 763 764 sctp_unhash_established(asoc); 765 sctp_association_free(asoc); 766 } 767 768 /* 769 * ADDIP Section 4.1 ASCONF Chunk Procedures 770 * A4) Start a T-4 RTO timer, using the RTO value of the selected 771 * destination address (we use active path instead of primary path just 772 * because primary path may be inactive. 773 */ 774 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, 775 struct sctp_association *asoc, 776 struct sctp_chunk *chunk) 777 { 778 struct sctp_transport *t; 779 780 t = asoc->peer.active_path; 781 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; 782 chunk->transport = t; 783 } 784 785 /* Process an incoming Operation Error Chunk. */ 786 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, 787 struct sctp_association *asoc, 788 struct sctp_chunk *chunk) 789 { 790 struct sctp_operr_chunk *operr_chunk; 791 struct sctp_errhdr *err_hdr; 792 793 operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr; 794 err_hdr = &operr_chunk->err_hdr; 795 796 switch (err_hdr->cause) { 797 case SCTP_ERROR_UNKNOWN_CHUNK: 798 { 799 struct sctp_chunkhdr *unk_chunk_hdr; 800 801 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable; 802 switch (unk_chunk_hdr->type) { 803 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an 804 * ERROR chunk reporting that it did not recognized the ASCONF 805 * chunk type, the sender of the ASCONF MUST NOT send any 806 * further ASCONF chunks and MUST stop its T-4 timer. 807 */ 808 case SCTP_CID_ASCONF: 809 asoc->peer.asconf_capable = 0; 810 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, 811 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); 812 break; 813 default: 814 break; 815 } 816 break; 817 } 818 default: 819 break; 820 } 821 } 822 823 /* Process variable FWDTSN chunk information. */ 824 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 825 struct sctp_chunk *chunk) 826 { 827 struct sctp_fwdtsn_skip *skip; 828 /* Walk through all the skipped SSNs */ 829 sctp_walk_fwdtsn(skip, chunk) { 830 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); 831 } 832 833 return; 834 } 835 836 /* Helper function to remove the association non-primary peer 837 * transports. 838 */ 839 static void sctp_cmd_del_non_primary(struct sctp_association *asoc) 840 { 841 struct sctp_transport *t; 842 struct list_head *pos; 843 struct list_head *temp; 844 845 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { 846 t = list_entry(pos, struct sctp_transport, transports); 847 if (!sctp_cmp_addr_exact(&t->ipaddr, 848 &asoc->peer.primary_addr)) { 849 sctp_assoc_del_peer(asoc, &t->ipaddr); 850 } 851 } 852 853 return; 854 } 855 856 /* Helper function to set sk_err on a 1-1 style socket. */ 857 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) 858 { 859 struct sock *sk = asoc->base.sk; 860 861 if (!sctp_style(sk, UDP)) 862 sk->sk_err = error; 863 } 864 865 /* Helper function to generate an association change event */ 866 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands, 867 struct sctp_association *asoc, 868 u8 state) 869 { 870 struct sctp_ulpevent *ev; 871 872 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0, 873 asoc->c.sinit_num_ostreams, 874 asoc->c.sinit_max_instreams, 875 NULL, GFP_ATOMIC); 876 if (ev) 877 sctp_ulpq_tail_event(&asoc->ulpq, ev); 878 } 879 880 /* Helper function to generate an adaptation indication event */ 881 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands, 882 struct sctp_association *asoc) 883 { 884 struct sctp_ulpevent *ev; 885 886 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); 887 888 if (ev) 889 sctp_ulpq_tail_event(&asoc->ulpq, ev); 890 } 891 892 /* These three macros allow us to pull the debugging code out of the 893 * main flow of sctp_do_sm() to keep attention focused on the real 894 * functionality there. 895 */ 896 #define DEBUG_PRE \ 897 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ 898 "ep %p, %s, %s, asoc %p[%s], %s\n", \ 899 ep, sctp_evttype_tbl[event_type], \ 900 (*debug_fn)(subtype), asoc, \ 901 sctp_state_tbl[state], state_fn->name) 902 903 #define DEBUG_POST \ 904 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ 905 "asoc %p, status: %s\n", \ 906 asoc, sctp_status_tbl[status]) 907 908 #define DEBUG_POST_SFX \ 909 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ 910 error, asoc, \ 911 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ 912 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED]) 913 914 /* 915 * This is the master state machine processing function. 916 * 917 * If you want to understand all of lksctp, this is a 918 * good place to start. 919 */ 920 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype, 921 sctp_state_t state, 922 struct sctp_endpoint *ep, 923 struct sctp_association *asoc, 924 void *event_arg, 925 gfp_t gfp) 926 { 927 sctp_cmd_seq_t commands; 928 const sctp_sm_table_entry_t *state_fn; 929 sctp_disposition_t status; 930 int error = 0; 931 typedef const char *(printfn_t)(sctp_subtype_t); 932 933 static printfn_t *table[] = { 934 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, 935 }; 936 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; 937 938 /* Look up the state function, run it, and then process the 939 * side effects. These three steps are the heart of lksctp. 940 */ 941 state_fn = sctp_sm_lookup_event(event_type, state, subtype); 942 943 sctp_init_cmd_seq(&commands); 944 945 DEBUG_PRE; 946 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands); 947 DEBUG_POST; 948 949 error = sctp_side_effects(event_type, subtype, state, 950 ep, asoc, event_arg, status, 951 &commands, gfp); 952 DEBUG_POST_SFX; 953 954 return error; 955 } 956 957 #undef DEBUG_PRE 958 #undef DEBUG_POST 959 960 /***************************************************************** 961 * This the master state function side effect processing function. 962 *****************************************************************/ 963 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 964 sctp_state_t state, 965 struct sctp_endpoint *ep, 966 struct sctp_association *asoc, 967 void *event_arg, 968 sctp_disposition_t status, 969 sctp_cmd_seq_t *commands, 970 gfp_t gfp) 971 { 972 int error; 973 974 /* FIXME - Most of the dispositions left today would be categorized 975 * as "exceptional" dispositions. For those dispositions, it 976 * may not be proper to run through any of the commands at all. 977 * For example, the command interpreter might be run only with 978 * disposition SCTP_DISPOSITION_CONSUME. 979 */ 980 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, 981 ep, asoc, 982 event_arg, status, 983 commands, gfp))) 984 goto bail; 985 986 switch (status) { 987 case SCTP_DISPOSITION_DISCARD: 988 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " 989 "event_type %d, event_id %d\n", 990 state, event_type, subtype.chunk); 991 break; 992 993 case SCTP_DISPOSITION_NOMEM: 994 /* We ran out of memory, so we need to discard this 995 * packet. 996 */ 997 /* BUG--we should now recover some memory, probably by 998 * reneging... 999 */ 1000 error = -ENOMEM; 1001 break; 1002 1003 case SCTP_DISPOSITION_DELETE_TCB: 1004 /* This should now be a command. */ 1005 break; 1006 1007 case SCTP_DISPOSITION_CONSUME: 1008 case SCTP_DISPOSITION_ABORT: 1009 /* 1010 * We should no longer have much work to do here as the 1011 * real work has been done as explicit commands above. 1012 */ 1013 break; 1014 1015 case SCTP_DISPOSITION_VIOLATION: 1016 printk(KERN_ERR "sctp protocol violation state %d " 1017 "chunkid %d\n", state, subtype.chunk); 1018 break; 1019 1020 case SCTP_DISPOSITION_NOT_IMPL: 1021 printk(KERN_WARNING "sctp unimplemented feature in state %d, " 1022 "event_type %d, event_id %d\n", 1023 state, event_type, subtype.chunk); 1024 break; 1025 1026 case SCTP_DISPOSITION_BUG: 1027 printk(KERN_ERR "sctp bug in state %d, " 1028 "event_type %d, event_id %d\n", 1029 state, event_type, subtype.chunk); 1030 BUG(); 1031 break; 1032 1033 default: 1034 printk(KERN_ERR "sctp impossible disposition %d " 1035 "in state %d, event_type %d, event_id %d\n", 1036 status, state, event_type, subtype.chunk); 1037 BUG(); 1038 break; 1039 } 1040 1041 bail: 1042 return error; 1043 } 1044 1045 /******************************************************************** 1046 * 2nd Level Abstractions 1047 ********************************************************************/ 1048 1049 /* This is the side-effect interpreter. */ 1050 static int sctp_cmd_interpreter(sctp_event_t event_type, 1051 sctp_subtype_t subtype, 1052 sctp_state_t state, 1053 struct sctp_endpoint *ep, 1054 struct sctp_association *asoc, 1055 void *event_arg, 1056 sctp_disposition_t status, 1057 sctp_cmd_seq_t *commands, 1058 gfp_t gfp) 1059 { 1060 int error = 0; 1061 int force; 1062 sctp_cmd_t *cmd; 1063 struct sctp_chunk *new_obj; 1064 struct sctp_chunk *chunk = NULL; 1065 struct sctp_packet *packet; 1066 struct list_head *pos; 1067 struct timer_list *timer; 1068 unsigned long timeout; 1069 struct sctp_transport *t; 1070 struct sctp_sackhdr sackh; 1071 int local_cork = 0; 1072 1073 if (SCTP_EVENT_T_TIMEOUT != event_type) 1074 chunk = (struct sctp_chunk *) event_arg; 1075 1076 /* Note: This whole file is a huge candidate for rework. 1077 * For example, each command could either have its own handler, so 1078 * the loop would look like: 1079 * while (cmds) 1080 * cmd->handle(x, y, z) 1081 * --jgrimm 1082 */ 1083 while (NULL != (cmd = sctp_next_cmd(commands))) { 1084 switch (cmd->verb) { 1085 case SCTP_CMD_NOP: 1086 /* Do nothing. */ 1087 break; 1088 1089 case SCTP_CMD_NEW_ASOC: 1090 /* Register a new association. */ 1091 if (local_cork) { 1092 sctp_outq_uncork(&asoc->outqueue); 1093 local_cork = 0; 1094 } 1095 asoc = cmd->obj.ptr; 1096 /* Register with the endpoint. */ 1097 sctp_endpoint_add_asoc(ep, asoc); 1098 sctp_hash_established(asoc); 1099 break; 1100 1101 case SCTP_CMD_UPDATE_ASSOC: 1102 sctp_assoc_update(asoc, cmd->obj.ptr); 1103 break; 1104 1105 case SCTP_CMD_PURGE_OUTQUEUE: 1106 sctp_outq_teardown(&asoc->outqueue); 1107 break; 1108 1109 case SCTP_CMD_DELETE_TCB: 1110 if (local_cork) { 1111 sctp_outq_uncork(&asoc->outqueue); 1112 local_cork = 0; 1113 } 1114 /* Delete the current association. */ 1115 sctp_cmd_delete_tcb(commands, asoc); 1116 asoc = NULL; 1117 break; 1118 1119 case SCTP_CMD_NEW_STATE: 1120 /* Enter a new state. */ 1121 sctp_cmd_new_state(commands, asoc, cmd->obj.state); 1122 break; 1123 1124 case SCTP_CMD_REPORT_TSN: 1125 /* Record the arrival of a TSN. */ 1126 sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32); 1127 break; 1128 1129 case SCTP_CMD_REPORT_FWDTSN: 1130 /* Move the Cumulattive TSN Ack ahead. */ 1131 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); 1132 1133 /* Abort any in progress partial delivery. */ 1134 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 1135 break; 1136 1137 case SCTP_CMD_PROCESS_FWDTSN: 1138 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr); 1139 break; 1140 1141 case SCTP_CMD_GEN_SACK: 1142 /* Generate a Selective ACK. 1143 * The argument tells us whether to just count 1144 * the packet and MAYBE generate a SACK, or 1145 * force a SACK out. 1146 */ 1147 force = cmd->obj.i32; 1148 error = sctp_gen_sack(asoc, force, commands); 1149 break; 1150 1151 case SCTP_CMD_PROCESS_SACK: 1152 /* Process an inbound SACK. */ 1153 error = sctp_cmd_process_sack(commands, asoc, 1154 cmd->obj.ptr); 1155 break; 1156 1157 case SCTP_CMD_GEN_INIT_ACK: 1158 /* Generate an INIT ACK chunk. */ 1159 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 1160 0); 1161 if (!new_obj) 1162 goto nomem; 1163 1164 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1165 SCTP_CHUNK(new_obj)); 1166 break; 1167 1168 case SCTP_CMD_PEER_INIT: 1169 /* Process a unified INIT from the peer. 1170 * Note: Only used during INIT-ACK processing. If 1171 * there is an error just return to the outter 1172 * layer which will bail. 1173 */ 1174 error = sctp_cmd_process_init(commands, asoc, chunk, 1175 cmd->obj.ptr, gfp); 1176 break; 1177 1178 case SCTP_CMD_GEN_COOKIE_ECHO: 1179 /* Generate a COOKIE ECHO chunk. */ 1180 new_obj = sctp_make_cookie_echo(asoc, chunk); 1181 if (!new_obj) { 1182 if (cmd->obj.ptr) 1183 sctp_chunk_free(cmd->obj.ptr); 1184 goto nomem; 1185 } 1186 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1187 SCTP_CHUNK(new_obj)); 1188 1189 /* If there is an ERROR chunk to be sent along with 1190 * the COOKIE_ECHO, send it, too. 1191 */ 1192 if (cmd->obj.ptr) 1193 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1194 SCTP_CHUNK(cmd->obj.ptr)); 1195 1196 /* FIXME - Eventually come up with a cleaner way to 1197 * enabling COOKIE-ECHO + DATA bundling during 1198 * multihoming stale cookie scenarios, the following 1199 * command plays with asoc->peer.retran_path to 1200 * avoid the problem of sending the COOKIE-ECHO and 1201 * DATA in different paths, which could result 1202 * in the association being ABORTed if the DATA chunk 1203 * is processed first by the server. Checking the 1204 * init error counter simply causes this command 1205 * to be executed only during failed attempts of 1206 * association establishment. 1207 */ 1208 if ((asoc->peer.retran_path != 1209 asoc->peer.primary_path) && 1210 (asoc->init_err_counter > 0)) { 1211 sctp_add_cmd_sf(commands, 1212 SCTP_CMD_FORCE_PRIM_RETRAN, 1213 SCTP_NULL()); 1214 } 1215 1216 break; 1217 1218 case SCTP_CMD_GEN_SHUTDOWN: 1219 /* Generate SHUTDOWN when in SHUTDOWN_SENT state. 1220 * Reset error counts. 1221 */ 1222 asoc->overall_error_count = 0; 1223 1224 /* Generate a SHUTDOWN chunk. */ 1225 new_obj = sctp_make_shutdown(asoc, chunk); 1226 if (!new_obj) 1227 goto nomem; 1228 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1229 SCTP_CHUNK(new_obj)); 1230 break; 1231 1232 case SCTP_CMD_CHUNK_ULP: 1233 /* Send a chunk to the sockets layer. */ 1234 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1235 "chunk_up:", cmd->obj.ptr, 1236 "ulpq:", &asoc->ulpq); 1237 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, 1238 GFP_ATOMIC); 1239 break; 1240 1241 case SCTP_CMD_EVENT_ULP: 1242 /* Send a notification to the sockets layer. */ 1243 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1244 "event_up:",cmd->obj.ptr, 1245 "ulpq:",&asoc->ulpq); 1246 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); 1247 break; 1248 1249 case SCTP_CMD_REPLY: 1250 /* If an caller has not already corked, do cork. */ 1251 if (!asoc->outqueue.cork) { 1252 sctp_outq_cork(&asoc->outqueue); 1253 local_cork = 1; 1254 } 1255 /* Send a chunk to our peer. */ 1256 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr); 1257 break; 1258 1259 case SCTP_CMD_SEND_PKT: 1260 /* Send a full packet to our peer. */ 1261 packet = cmd->obj.ptr; 1262 sctp_packet_transmit(packet); 1263 sctp_ootb_pkt_free(packet); 1264 break; 1265 1266 case SCTP_CMD_RETRAN: 1267 /* Mark a transport for retransmission. */ 1268 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1269 SCTP_RTXR_T3_RTX); 1270 break; 1271 1272 case SCTP_CMD_TRANSMIT: 1273 /* Kick start transmission. */ 1274 error = sctp_outq_uncork(&asoc->outqueue); 1275 local_cork = 0; 1276 break; 1277 1278 case SCTP_CMD_ECN_CE: 1279 /* Do delayed CE processing. */ 1280 sctp_do_ecn_ce_work(asoc, cmd->obj.u32); 1281 break; 1282 1283 case SCTP_CMD_ECN_ECNE: 1284 /* Do delayed ECNE processing. */ 1285 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, 1286 chunk); 1287 if (new_obj) 1288 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1289 SCTP_CHUNK(new_obj)); 1290 break; 1291 1292 case SCTP_CMD_ECN_CWR: 1293 /* Do delayed CWR processing. */ 1294 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); 1295 break; 1296 1297 case SCTP_CMD_SETUP_T2: 1298 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr); 1299 break; 1300 1301 case SCTP_CMD_TIMER_START: 1302 timer = &asoc->timers[cmd->obj.to]; 1303 timeout = asoc->timeouts[cmd->obj.to]; 1304 BUG_ON(!timeout); 1305 1306 timer->expires = jiffies + timeout; 1307 sctp_association_hold(asoc); 1308 add_timer(timer); 1309 break; 1310 1311 case SCTP_CMD_TIMER_RESTART: 1312 timer = &asoc->timers[cmd->obj.to]; 1313 timeout = asoc->timeouts[cmd->obj.to]; 1314 if (!mod_timer(timer, jiffies + timeout)) 1315 sctp_association_hold(asoc); 1316 break; 1317 1318 case SCTP_CMD_TIMER_STOP: 1319 timer = &asoc->timers[cmd->obj.to]; 1320 if (timer_pending(timer) && del_timer(timer)) 1321 sctp_association_put(asoc); 1322 break; 1323 1324 case SCTP_CMD_INIT_CHOOSE_TRANSPORT: 1325 chunk = cmd->obj.ptr; 1326 t = sctp_assoc_choose_init_transport(asoc); 1327 asoc->init_last_sent_to = t; 1328 chunk->transport = t; 1329 t->init_sent_count++; 1330 break; 1331 1332 case SCTP_CMD_INIT_RESTART: 1333 /* Do the needed accounting and updates 1334 * associated with restarting an initialization 1335 * timer. Only multiply the timeout by two if 1336 * all transports have been tried at the current 1337 * timeout. 1338 */ 1339 t = asoc->init_last_sent_to; 1340 asoc->init_err_counter++; 1341 1342 if (t->init_sent_count > (asoc->init_cycle + 1)) { 1343 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2; 1344 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] > 1345 asoc->max_init_timeo) { 1346 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 1347 asoc->max_init_timeo; 1348 } 1349 asoc->init_cycle++; 1350 SCTP_DEBUG_PRINTK( 1351 "T1 INIT Timeout adjustment" 1352 " init_err_counter: %d" 1353 " cycle: %d" 1354 " timeout: %ld\n", 1355 asoc->init_err_counter, 1356 asoc->init_cycle, 1357 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]); 1358 } 1359 1360 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 1361 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); 1362 break; 1363 1364 case SCTP_CMD_COOKIEECHO_RESTART: 1365 /* Do the needed accounting and updates 1366 * associated with restarting an initialization 1367 * timer. Only multiply the timeout by two if 1368 * all transports have been tried at the current 1369 * timeout. 1370 */ 1371 asoc->init_err_counter++; 1372 1373 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2; 1374 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] > 1375 asoc->max_init_timeo) { 1376 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 1377 asoc->max_init_timeo; 1378 } 1379 SCTP_DEBUG_PRINTK( 1380 "T1 COOKIE Timeout adjustment" 1381 " init_err_counter: %d" 1382 " timeout: %ld\n", 1383 asoc->init_err_counter, 1384 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]); 1385 1386 /* If we've sent any data bundled with 1387 * COOKIE-ECHO we need to resend. 1388 */ 1389 list_for_each(pos, &asoc->peer.transport_addr_list) { 1390 t = list_entry(pos, struct sctp_transport, 1391 transports); 1392 sctp_retransmit_mark(&asoc->outqueue, t, 0); 1393 } 1394 1395 sctp_add_cmd_sf(commands, 1396 SCTP_CMD_TIMER_RESTART, 1397 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); 1398 break; 1399 1400 case SCTP_CMD_INIT_FAILED: 1401 sctp_cmd_init_failed(commands, asoc, cmd->obj.err); 1402 break; 1403 1404 case SCTP_CMD_ASSOC_FAILED: 1405 sctp_cmd_assoc_failed(commands, asoc, event_type, 1406 subtype, chunk, cmd->obj.err); 1407 break; 1408 1409 case SCTP_CMD_INIT_COUNTER_INC: 1410 asoc->init_err_counter++; 1411 break; 1412 1413 case SCTP_CMD_INIT_COUNTER_RESET: 1414 asoc->init_err_counter = 0; 1415 asoc->init_cycle = 0; 1416 break; 1417 1418 case SCTP_CMD_REPORT_DUP: 1419 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, 1420 cmd->obj.u32); 1421 break; 1422 1423 case SCTP_CMD_REPORT_BAD_TAG: 1424 SCTP_DEBUG_PRINTK("vtag mismatch!\n"); 1425 break; 1426 1427 case SCTP_CMD_STRIKE: 1428 /* Mark one strike against a transport. */ 1429 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport); 1430 break; 1431 1432 case SCTP_CMD_TRANSPORT_RESET: 1433 t = cmd->obj.transport; 1434 sctp_cmd_transport_reset(commands, asoc, t); 1435 break; 1436 1437 case SCTP_CMD_TRANSPORT_ON: 1438 t = cmd->obj.transport; 1439 sctp_cmd_transport_on(commands, asoc, t, chunk); 1440 break; 1441 1442 case SCTP_CMD_HB_TIMERS_START: 1443 sctp_cmd_hb_timers_start(commands, asoc); 1444 break; 1445 1446 case SCTP_CMD_HB_TIMER_UPDATE: 1447 t = cmd->obj.transport; 1448 sctp_cmd_hb_timer_update(commands, asoc, t); 1449 break; 1450 1451 case SCTP_CMD_HB_TIMERS_STOP: 1452 sctp_cmd_hb_timers_stop(commands, asoc); 1453 break; 1454 1455 case SCTP_CMD_REPORT_ERROR: 1456 error = cmd->obj.error; 1457 break; 1458 1459 case SCTP_CMD_PROCESS_CTSN: 1460 /* Dummy up a SACK for processing. */ 1461 sackh.cum_tsn_ack = cmd->obj.be32; 1462 sackh.a_rwnd = 0; 1463 sackh.num_gap_ack_blocks = 0; 1464 sackh.num_dup_tsns = 0; 1465 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, 1466 SCTP_SACKH(&sackh)); 1467 break; 1468 1469 case SCTP_CMD_DISCARD_PACKET: 1470 /* We need to discard the whole packet. */ 1471 chunk->pdiscard = 1; 1472 break; 1473 1474 case SCTP_CMD_RTO_PENDING: 1475 t = cmd->obj.transport; 1476 t->rto_pending = 1; 1477 break; 1478 1479 case SCTP_CMD_PART_DELIVER: 1480 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr, 1481 GFP_ATOMIC); 1482 break; 1483 1484 case SCTP_CMD_RENEGE: 1485 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, 1486 GFP_ATOMIC); 1487 break; 1488 1489 case SCTP_CMD_SETUP_T4: 1490 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); 1491 break; 1492 1493 case SCTP_CMD_PROCESS_OPERR: 1494 sctp_cmd_process_operr(commands, asoc, chunk); 1495 break; 1496 case SCTP_CMD_CLEAR_INIT_TAG: 1497 asoc->peer.i.init_tag = 0; 1498 break; 1499 case SCTP_CMD_DEL_NON_PRIMARY: 1500 sctp_cmd_del_non_primary(asoc); 1501 break; 1502 case SCTP_CMD_T3_RTX_TIMERS_STOP: 1503 sctp_cmd_t3_rtx_timers_stop(commands, asoc); 1504 break; 1505 case SCTP_CMD_FORCE_PRIM_RETRAN: 1506 t = asoc->peer.retran_path; 1507 asoc->peer.retran_path = asoc->peer.primary_path; 1508 error = sctp_outq_uncork(&asoc->outqueue); 1509 local_cork = 0; 1510 asoc->peer.retran_path = t; 1511 break; 1512 case SCTP_CMD_SET_SK_ERR: 1513 sctp_cmd_set_sk_err(asoc, cmd->obj.error); 1514 break; 1515 case SCTP_CMD_ASSOC_CHANGE: 1516 sctp_cmd_assoc_change(commands, asoc, 1517 cmd->obj.u8); 1518 break; 1519 case SCTP_CMD_ADAPTATION_IND: 1520 sctp_cmd_adaptation_ind(commands, asoc); 1521 break; 1522 1523 default: 1524 printk(KERN_WARNING "Impossible command: %u, %p\n", 1525 cmd->verb, cmd->obj.ptr); 1526 break; 1527 } 1528 1529 if (error) 1530 break; 1531 } 1532 1533 out: 1534 if (local_cork) 1535 sctp_outq_uncork(&asoc->outqueue); 1536 return error; 1537 nomem: 1538 error = -ENOMEM; 1539 goto out; 1540 } 1541 1542