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 error = sctp_outq_tail(&asoc->outqueue, 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 asoc->overall_error_count++; 434 435 if (transport->state != SCTP_INACTIVE && 436 (transport->error_count++ >= transport->pathmaxrxt)) { 437 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", 438 " transport IP: port:%d failed.\n", 439 asoc, 440 (&transport->ipaddr), 441 transport->ipaddr.v4.sin_port); 442 sctp_assoc_control_transport(asoc, transport, 443 SCTP_TRANSPORT_DOWN, 444 SCTP_FAILED_THRESHOLD); 445 } 446 447 /* E2) For the destination address for which the timer 448 * expires, set RTO <- RTO * 2 ("back off the timer"). The 449 * maximum value discussed in rule C7 above (RTO.max) may be 450 * used to provide an upper bound to this doubling operation. 451 */ 452 transport->rto = min((transport->rto * 2), transport->asoc->rto_max); 453 } 454 455 /* Worker routine to handle INIT command failure. */ 456 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, 457 struct sctp_association *asoc, 458 unsigned error) 459 { 460 struct sctp_ulpevent *event; 461 462 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC, 463 (__u16)error, 0, 0, 464 GFP_ATOMIC); 465 466 if (event) 467 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 468 SCTP_ULPEVENT(event)); 469 470 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 471 SCTP_STATE(SCTP_STATE_CLOSED)); 472 473 /* SEND_FAILED sent later when cleaning up the association. */ 474 asoc->outqueue.error = error; 475 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 476 } 477 478 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ 479 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, 480 struct sctp_association *asoc, 481 sctp_event_t event_type, 482 sctp_subtype_t subtype, 483 struct sctp_chunk *chunk, 484 unsigned error) 485 { 486 struct sctp_ulpevent *event; 487 488 /* Cancel any partial delivery in progress. */ 489 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 490 491 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 492 (__u16)error, 0, 0, 493 GFP_ATOMIC); 494 if (event) 495 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 496 SCTP_ULPEVENT(event)); 497 498 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 499 SCTP_STATE(SCTP_STATE_CLOSED)); 500 501 /* SEND_FAILED sent later when cleaning up the association. */ 502 asoc->outqueue.error = error; 503 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 504 } 505 506 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT 507 * inside the cookie. In reality, this is only used for INIT-ACK processing 508 * since all other cases use "temporary" associations and can do all 509 * their work in statefuns directly. 510 */ 511 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, 512 struct sctp_association *asoc, 513 struct sctp_chunk *chunk, 514 sctp_init_chunk_t *peer_init, 515 gfp_t gfp) 516 { 517 int error; 518 519 /* We only process the init as a sideeffect in a single 520 * case. This is when we process the INIT-ACK. If we 521 * fail during INIT processing (due to malloc problems), 522 * just return the error and stop processing the stack. 523 */ 524 if (!sctp_process_init(asoc, chunk->chunk_hdr->type, 525 sctp_source(chunk), peer_init, gfp)) 526 error = -ENOMEM; 527 else 528 error = 0; 529 530 return error; 531 } 532 533 /* Helper function to break out starting up of heartbeat timers. */ 534 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, 535 struct sctp_association *asoc) 536 { 537 struct sctp_transport *t; 538 struct list_head *pos; 539 540 /* Start a heartbeat timer for each transport on the association. 541 * hold a reference on the transport to make sure none of 542 * the needed data structures go away. 543 */ 544 list_for_each(pos, &asoc->peer.transport_addr_list) { 545 t = list_entry(pos, struct sctp_transport, transports); 546 547 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 548 sctp_transport_hold(t); 549 } 550 } 551 552 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, 553 struct sctp_association *asoc) 554 { 555 struct sctp_transport *t; 556 struct list_head *pos; 557 558 /* Stop all heartbeat timers. */ 559 560 list_for_each(pos, &asoc->peer.transport_addr_list) { 561 t = list_entry(pos, struct sctp_transport, transports); 562 if (del_timer(&t->hb_timer)) 563 sctp_transport_put(t); 564 } 565 } 566 567 /* Helper function to stop any pending T3-RTX timers */ 568 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, 569 struct sctp_association *asoc) 570 { 571 struct sctp_transport *t; 572 struct list_head *pos; 573 574 list_for_each(pos, &asoc->peer.transport_addr_list) { 575 t = list_entry(pos, struct sctp_transport, transports); 576 if (timer_pending(&t->T3_rtx_timer) && 577 del_timer(&t->T3_rtx_timer)) { 578 sctp_transport_put(t); 579 } 580 } 581 } 582 583 584 /* Helper function to update the heartbeat timer. */ 585 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, 586 struct sctp_association *asoc, 587 struct sctp_transport *t) 588 { 589 /* Update the heartbeat timer. */ 590 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 591 sctp_transport_hold(t); 592 } 593 594 /* Helper function to handle the reception of an HEARTBEAT ACK. */ 595 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, 596 struct sctp_association *asoc, 597 struct sctp_transport *t, 598 struct sctp_chunk *chunk) 599 { 600 sctp_sender_hb_info_t *hbinfo; 601 602 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the 603 * HEARTBEAT should clear the error counter of the destination 604 * transport address to which the HEARTBEAT was sent. 605 * The association's overall error count is also cleared. 606 */ 607 t->error_count = 0; 608 t->asoc->overall_error_count = 0; 609 610 /* Mark the destination transport address as active if it is not so 611 * marked. 612 */ 613 if (t->state == SCTP_INACTIVE) 614 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, 615 SCTP_HEARTBEAT_SUCCESS); 616 617 /* The receiver of the HEARTBEAT ACK should also perform an 618 * RTT measurement for that destination transport address 619 * using the time value carried in the HEARTBEAT ACK chunk. 620 */ 621 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; 622 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); 623 } 624 625 /* Helper function to do a transport reset at the expiry of the hearbeat 626 * timer. 627 */ 628 static void sctp_cmd_transport_reset(sctp_cmd_seq_t *cmds, 629 struct sctp_association *asoc, 630 struct sctp_transport *t) 631 { 632 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); 633 634 /* Mark one strike against a transport. */ 635 sctp_do_8_2_transport_strike(asoc, t); 636 } 637 638 /* Helper function to process the process SACK command. */ 639 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, 640 struct sctp_association *asoc, 641 struct sctp_sackhdr *sackh) 642 { 643 int err; 644 645 if (sctp_outq_sack(&asoc->outqueue, sackh)) { 646 /* There are no more TSNs awaiting SACK. */ 647 err = sctp_do_sm(SCTP_EVENT_T_OTHER, 648 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), 649 asoc->state, asoc->ep, asoc, NULL, 650 GFP_ATOMIC); 651 } else { 652 /* Windows may have opened, so we need 653 * to check if we have DATA to transmit 654 */ 655 err = sctp_outq_flush(&asoc->outqueue, 0); 656 } 657 658 return err; 659 } 660 661 /* Helper function to set the timeout value for T2-SHUTDOWN timer and to set 662 * the transport for a shutdown chunk. 663 */ 664 static void sctp_cmd_setup_t2(sctp_cmd_seq_t *cmds, 665 struct sctp_association *asoc, 666 struct sctp_chunk *chunk) 667 { 668 struct sctp_transport *t; 669 670 t = sctp_assoc_choose_shutdown_transport(asoc); 671 asoc->shutdown_last_sent_to = t; 672 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; 673 chunk->transport = t; 674 } 675 676 /* Helper function to change the state of an association. */ 677 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 678 struct sctp_association *asoc, 679 sctp_state_t state) 680 { 681 struct sock *sk = asoc->base.sk; 682 683 asoc->state = state; 684 685 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", 686 asoc, sctp_state_tbl[state]); 687 688 if (sctp_style(sk, TCP)) { 689 /* Change the sk->sk_state of a TCP-style socket that has 690 * sucessfully completed a connect() call. 691 */ 692 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) 693 sk->sk_state = SCTP_SS_ESTABLISHED; 694 695 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ 696 if (sctp_state(asoc, SHUTDOWN_RECEIVED) && 697 sctp_sstate(sk, ESTABLISHED)) 698 sk->sk_shutdown |= RCV_SHUTDOWN; 699 } 700 701 if (sctp_state(asoc, COOKIE_WAIT)) { 702 /* Reset init timeouts since they may have been 703 * increased due to timer expirations. 704 */ 705 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 706 asoc->rto_initial; 707 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 708 asoc->rto_initial; 709 } 710 711 if (sctp_state(asoc, ESTABLISHED) || 712 sctp_state(asoc, CLOSED) || 713 sctp_state(asoc, SHUTDOWN_RECEIVED)) { 714 /* Wake up any processes waiting in the asoc's wait queue in 715 * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). 716 */ 717 if (waitqueue_active(&asoc->wait)) 718 wake_up_interruptible(&asoc->wait); 719 720 /* Wake up any processes waiting in the sk's sleep queue of 721 * a TCP-style or UDP-style peeled-off socket in 722 * sctp_wait_for_accept() or sctp_wait_for_packet(). 723 * For a UDP-style socket, the waiters are woken up by the 724 * notifications. 725 */ 726 if (!sctp_style(sk, UDP)) 727 sk->sk_state_change(sk); 728 } 729 } 730 731 /* Helper function to delete an association. */ 732 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, 733 struct sctp_association *asoc) 734 { 735 struct sock *sk = asoc->base.sk; 736 737 /* If it is a non-temporary association belonging to a TCP-style 738 * listening socket that is not closed, do not free it so that accept() 739 * can pick it up later. 740 */ 741 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && 742 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) 743 return; 744 745 sctp_unhash_established(asoc); 746 sctp_association_free(asoc); 747 } 748 749 /* 750 * ADDIP Section 4.1 ASCONF Chunk Procedures 751 * A4) Start a T-4 RTO timer, using the RTO value of the selected 752 * destination address (we use active path instead of primary path just 753 * because primary path may be inactive. 754 */ 755 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, 756 struct sctp_association *asoc, 757 struct sctp_chunk *chunk) 758 { 759 struct sctp_transport *t; 760 761 t = asoc->peer.active_path; 762 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; 763 chunk->transport = t; 764 } 765 766 /* Process an incoming Operation Error Chunk. */ 767 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, 768 struct sctp_association *asoc, 769 struct sctp_chunk *chunk) 770 { 771 struct sctp_operr_chunk *operr_chunk; 772 struct sctp_errhdr *err_hdr; 773 774 operr_chunk = (struct sctp_operr_chunk *)chunk->chunk_hdr; 775 err_hdr = &operr_chunk->err_hdr; 776 777 switch (err_hdr->cause) { 778 case SCTP_ERROR_UNKNOWN_CHUNK: 779 { 780 struct sctp_chunkhdr *unk_chunk_hdr; 781 782 unk_chunk_hdr = (struct sctp_chunkhdr *)err_hdr->variable; 783 switch (unk_chunk_hdr->type) { 784 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with an 785 * ERROR chunk reporting that it did not recognized the ASCONF 786 * chunk type, the sender of the ASCONF MUST NOT send any 787 * further ASCONF chunks and MUST stop its T-4 timer. 788 */ 789 case SCTP_CID_ASCONF: 790 asoc->peer.asconf_capable = 0; 791 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, 792 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); 793 break; 794 default: 795 break; 796 } 797 break; 798 } 799 default: 800 break; 801 } 802 } 803 804 /* Process variable FWDTSN chunk information. */ 805 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 806 struct sctp_chunk *chunk) 807 { 808 struct sctp_fwdtsn_skip *skip; 809 /* Walk through all the skipped SSNs */ 810 sctp_walk_fwdtsn(skip, chunk) { 811 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); 812 } 813 814 return; 815 } 816 817 /* Helper function to remove the association non-primary peer 818 * transports. 819 */ 820 static void sctp_cmd_del_non_primary(struct sctp_association *asoc) 821 { 822 struct sctp_transport *t; 823 struct list_head *pos; 824 struct list_head *temp; 825 826 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { 827 t = list_entry(pos, struct sctp_transport, transports); 828 if (!sctp_cmp_addr_exact(&t->ipaddr, 829 &asoc->peer.primary_addr)) { 830 sctp_assoc_del_peer(asoc, &t->ipaddr); 831 } 832 } 833 834 return; 835 } 836 837 /* Helper function to set sk_err on a 1-1 style socket. */ 838 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) 839 { 840 struct sock *sk = asoc->base.sk; 841 842 if (!sctp_style(sk, UDP)) 843 sk->sk_err = error; 844 } 845 846 /* These three macros allow us to pull the debugging code out of the 847 * main flow of sctp_do_sm() to keep attention focused on the real 848 * functionality there. 849 */ 850 #define DEBUG_PRE \ 851 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ 852 "ep %p, %s, %s, asoc %p[%s], %s\n", \ 853 ep, sctp_evttype_tbl[event_type], \ 854 (*debug_fn)(subtype), asoc, \ 855 sctp_state_tbl[state], state_fn->name) 856 857 #define DEBUG_POST \ 858 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ 859 "asoc %p, status: %s\n", \ 860 asoc, sctp_status_tbl[status]) 861 862 #define DEBUG_POST_SFX \ 863 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ 864 error, asoc, \ 865 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ 866 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED]) 867 868 /* 869 * This is the master state machine processing function. 870 * 871 * If you want to understand all of lksctp, this is a 872 * good place to start. 873 */ 874 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype, 875 sctp_state_t state, 876 struct sctp_endpoint *ep, 877 struct sctp_association *asoc, 878 void *event_arg, 879 gfp_t gfp) 880 { 881 sctp_cmd_seq_t commands; 882 const sctp_sm_table_entry_t *state_fn; 883 sctp_disposition_t status; 884 int error = 0; 885 typedef const char *(printfn_t)(sctp_subtype_t); 886 887 static printfn_t *table[] = { 888 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, 889 }; 890 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; 891 892 /* Look up the state function, run it, and then process the 893 * side effects. These three steps are the heart of lksctp. 894 */ 895 state_fn = sctp_sm_lookup_event(event_type, state, subtype); 896 897 sctp_init_cmd_seq(&commands); 898 899 DEBUG_PRE; 900 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands); 901 DEBUG_POST; 902 903 error = sctp_side_effects(event_type, subtype, state, 904 ep, asoc, event_arg, status, 905 &commands, gfp); 906 DEBUG_POST_SFX; 907 908 return error; 909 } 910 911 #undef DEBUG_PRE 912 #undef DEBUG_POST 913 914 /***************************************************************** 915 * This the master state function side effect processing function. 916 *****************************************************************/ 917 static int sctp_side_effects(sctp_event_t event_type, sctp_subtype_t subtype, 918 sctp_state_t state, 919 struct sctp_endpoint *ep, 920 struct sctp_association *asoc, 921 void *event_arg, 922 sctp_disposition_t status, 923 sctp_cmd_seq_t *commands, 924 gfp_t gfp) 925 { 926 int error; 927 928 /* FIXME - Most of the dispositions left today would be categorized 929 * as "exceptional" dispositions. For those dispositions, it 930 * may not be proper to run through any of the commands at all. 931 * For example, the command interpreter might be run only with 932 * disposition SCTP_DISPOSITION_CONSUME. 933 */ 934 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, 935 ep, asoc, 936 event_arg, status, 937 commands, gfp))) 938 goto bail; 939 940 switch (status) { 941 case SCTP_DISPOSITION_DISCARD: 942 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " 943 "event_type %d, event_id %d\n", 944 state, event_type, subtype.chunk); 945 break; 946 947 case SCTP_DISPOSITION_NOMEM: 948 /* We ran out of memory, so we need to discard this 949 * packet. 950 */ 951 /* BUG--we should now recover some memory, probably by 952 * reneging... 953 */ 954 error = -ENOMEM; 955 break; 956 957 case SCTP_DISPOSITION_DELETE_TCB: 958 /* This should now be a command. */ 959 break; 960 961 case SCTP_DISPOSITION_CONSUME: 962 case SCTP_DISPOSITION_ABORT: 963 /* 964 * We should no longer have much work to do here as the 965 * real work has been done as explicit commands above. 966 */ 967 break; 968 969 case SCTP_DISPOSITION_VIOLATION: 970 printk(KERN_ERR "sctp protocol violation state %d " 971 "chunkid %d\n", state, subtype.chunk); 972 break; 973 974 case SCTP_DISPOSITION_NOT_IMPL: 975 printk(KERN_WARNING "sctp unimplemented feature in state %d, " 976 "event_type %d, event_id %d\n", 977 state, event_type, subtype.chunk); 978 break; 979 980 case SCTP_DISPOSITION_BUG: 981 printk(KERN_ERR "sctp bug in state %d, " 982 "event_type %d, event_id %d\n", 983 state, event_type, subtype.chunk); 984 BUG(); 985 break; 986 987 default: 988 printk(KERN_ERR "sctp impossible disposition %d " 989 "in state %d, event_type %d, event_id %d\n", 990 status, state, event_type, subtype.chunk); 991 BUG(); 992 break; 993 }; 994 995 bail: 996 return error; 997 } 998 999 /******************************************************************** 1000 * 2nd Level Abstractions 1001 ********************************************************************/ 1002 1003 /* This is the side-effect interpreter. */ 1004 static int sctp_cmd_interpreter(sctp_event_t event_type, 1005 sctp_subtype_t subtype, 1006 sctp_state_t state, 1007 struct sctp_endpoint *ep, 1008 struct sctp_association *asoc, 1009 void *event_arg, 1010 sctp_disposition_t status, 1011 sctp_cmd_seq_t *commands, 1012 gfp_t gfp) 1013 { 1014 int error = 0; 1015 int force; 1016 sctp_cmd_t *cmd; 1017 struct sctp_chunk *new_obj; 1018 struct sctp_chunk *chunk = NULL; 1019 struct sctp_packet *packet; 1020 struct list_head *pos; 1021 struct timer_list *timer; 1022 unsigned long timeout; 1023 struct sctp_transport *t; 1024 struct sctp_sackhdr sackh; 1025 int local_cork = 0; 1026 1027 if (SCTP_EVENT_T_TIMEOUT != event_type) 1028 chunk = (struct sctp_chunk *) event_arg; 1029 1030 /* Note: This whole file is a huge candidate for rework. 1031 * For example, each command could either have its own handler, so 1032 * the loop would look like: 1033 * while (cmds) 1034 * cmd->handle(x, y, z) 1035 * --jgrimm 1036 */ 1037 while (NULL != (cmd = sctp_next_cmd(commands))) { 1038 switch (cmd->verb) { 1039 case SCTP_CMD_NOP: 1040 /* Do nothing. */ 1041 break; 1042 1043 case SCTP_CMD_NEW_ASOC: 1044 /* Register a new association. */ 1045 if (local_cork) { 1046 sctp_outq_uncork(&asoc->outqueue); 1047 local_cork = 0; 1048 } 1049 asoc = cmd->obj.ptr; 1050 /* Register with the endpoint. */ 1051 sctp_endpoint_add_asoc(ep, asoc); 1052 sctp_hash_established(asoc); 1053 break; 1054 1055 case SCTP_CMD_UPDATE_ASSOC: 1056 sctp_assoc_update(asoc, cmd->obj.ptr); 1057 break; 1058 1059 case SCTP_CMD_PURGE_OUTQUEUE: 1060 sctp_outq_teardown(&asoc->outqueue); 1061 break; 1062 1063 case SCTP_CMD_DELETE_TCB: 1064 if (local_cork) { 1065 sctp_outq_uncork(&asoc->outqueue); 1066 local_cork = 0; 1067 } 1068 /* Delete the current association. */ 1069 sctp_cmd_delete_tcb(commands, asoc); 1070 asoc = NULL; 1071 break; 1072 1073 case SCTP_CMD_NEW_STATE: 1074 /* Enter a new state. */ 1075 sctp_cmd_new_state(commands, asoc, cmd->obj.state); 1076 break; 1077 1078 case SCTP_CMD_REPORT_TSN: 1079 /* Record the arrival of a TSN. */ 1080 sctp_tsnmap_mark(&asoc->peer.tsn_map, cmd->obj.u32); 1081 break; 1082 1083 case SCTP_CMD_REPORT_FWDTSN: 1084 /* Move the Cumulattive TSN Ack ahead. */ 1085 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); 1086 1087 /* Abort any in progress partial delivery. */ 1088 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 1089 break; 1090 1091 case SCTP_CMD_PROCESS_FWDTSN: 1092 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr); 1093 break; 1094 1095 case SCTP_CMD_GEN_SACK: 1096 /* Generate a Selective ACK. 1097 * The argument tells us whether to just count 1098 * the packet and MAYBE generate a SACK, or 1099 * force a SACK out. 1100 */ 1101 force = cmd->obj.i32; 1102 error = sctp_gen_sack(asoc, force, commands); 1103 break; 1104 1105 case SCTP_CMD_PROCESS_SACK: 1106 /* Process an inbound SACK. */ 1107 error = sctp_cmd_process_sack(commands, asoc, 1108 cmd->obj.ptr); 1109 break; 1110 1111 case SCTP_CMD_GEN_INIT_ACK: 1112 /* Generate an INIT ACK chunk. */ 1113 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 1114 0); 1115 if (!new_obj) 1116 goto nomem; 1117 1118 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1119 SCTP_CHUNK(new_obj)); 1120 break; 1121 1122 case SCTP_CMD_PEER_INIT: 1123 /* Process a unified INIT from the peer. 1124 * Note: Only used during INIT-ACK processing. If 1125 * there is an error just return to the outter 1126 * layer which will bail. 1127 */ 1128 error = sctp_cmd_process_init(commands, asoc, chunk, 1129 cmd->obj.ptr, gfp); 1130 break; 1131 1132 case SCTP_CMD_GEN_COOKIE_ECHO: 1133 /* Generate a COOKIE ECHO chunk. */ 1134 new_obj = sctp_make_cookie_echo(asoc, chunk); 1135 if (!new_obj) { 1136 if (cmd->obj.ptr) 1137 sctp_chunk_free(cmd->obj.ptr); 1138 goto nomem; 1139 } 1140 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1141 SCTP_CHUNK(new_obj)); 1142 1143 /* If there is an ERROR chunk to be sent along with 1144 * the COOKIE_ECHO, send it, too. 1145 */ 1146 if (cmd->obj.ptr) 1147 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1148 SCTP_CHUNK(cmd->obj.ptr)); 1149 1150 /* FIXME - Eventually come up with a cleaner way to 1151 * enabling COOKIE-ECHO + DATA bundling during 1152 * multihoming stale cookie scenarios, the following 1153 * command plays with asoc->peer.retran_path to 1154 * avoid the problem of sending the COOKIE-ECHO and 1155 * DATA in different paths, which could result 1156 * in the association being ABORTed if the DATA chunk 1157 * is processed first by the server. Checking the 1158 * init error counter simply causes this command 1159 * to be executed only during failed attempts of 1160 * association establishment. 1161 */ 1162 if ((asoc->peer.retran_path != 1163 asoc->peer.primary_path) && 1164 (asoc->init_err_counter > 0)) { 1165 sctp_add_cmd_sf(commands, 1166 SCTP_CMD_FORCE_PRIM_RETRAN, 1167 SCTP_NULL()); 1168 } 1169 1170 break; 1171 1172 case SCTP_CMD_GEN_SHUTDOWN: 1173 /* Generate SHUTDOWN when in SHUTDOWN_SENT state. 1174 * Reset error counts. 1175 */ 1176 asoc->overall_error_count = 0; 1177 1178 /* Generate a SHUTDOWN chunk. */ 1179 new_obj = sctp_make_shutdown(asoc, chunk); 1180 if (!new_obj) 1181 goto nomem; 1182 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1183 SCTP_CHUNK(new_obj)); 1184 break; 1185 1186 case SCTP_CMD_CHUNK_ULP: 1187 /* Send a chunk to the sockets layer. */ 1188 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1189 "chunk_up:", cmd->obj.ptr, 1190 "ulpq:", &asoc->ulpq); 1191 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, 1192 GFP_ATOMIC); 1193 break; 1194 1195 case SCTP_CMD_EVENT_ULP: 1196 /* Send a notification to the sockets layer. */ 1197 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1198 "event_up:",cmd->obj.ptr, 1199 "ulpq:",&asoc->ulpq); 1200 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); 1201 break; 1202 1203 case SCTP_CMD_REPLY: 1204 /* If an caller has not already corked, do cork. */ 1205 if (!asoc->outqueue.cork) { 1206 sctp_outq_cork(&asoc->outqueue); 1207 local_cork = 1; 1208 } 1209 /* Send a chunk to our peer. */ 1210 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr); 1211 break; 1212 1213 case SCTP_CMD_SEND_PKT: 1214 /* Send a full packet to our peer. */ 1215 packet = cmd->obj.ptr; 1216 sctp_packet_transmit(packet); 1217 sctp_ootb_pkt_free(packet); 1218 break; 1219 1220 case SCTP_CMD_RETRAN: 1221 /* Mark a transport for retransmission. */ 1222 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1223 SCTP_RTXR_T3_RTX); 1224 break; 1225 1226 case SCTP_CMD_TRANSMIT: 1227 /* Kick start transmission. */ 1228 error = sctp_outq_uncork(&asoc->outqueue); 1229 local_cork = 0; 1230 break; 1231 1232 case SCTP_CMD_ECN_CE: 1233 /* Do delayed CE processing. */ 1234 sctp_do_ecn_ce_work(asoc, cmd->obj.u32); 1235 break; 1236 1237 case SCTP_CMD_ECN_ECNE: 1238 /* Do delayed ECNE processing. */ 1239 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, 1240 chunk); 1241 if (new_obj) 1242 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1243 SCTP_CHUNK(new_obj)); 1244 break; 1245 1246 case SCTP_CMD_ECN_CWR: 1247 /* Do delayed CWR processing. */ 1248 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); 1249 break; 1250 1251 case SCTP_CMD_SETUP_T2: 1252 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr); 1253 break; 1254 1255 case SCTP_CMD_TIMER_START: 1256 timer = &asoc->timers[cmd->obj.to]; 1257 timeout = asoc->timeouts[cmd->obj.to]; 1258 BUG_ON(!timeout); 1259 1260 timer->expires = jiffies + timeout; 1261 sctp_association_hold(asoc); 1262 add_timer(timer); 1263 break; 1264 1265 case SCTP_CMD_TIMER_RESTART: 1266 timer = &asoc->timers[cmd->obj.to]; 1267 timeout = asoc->timeouts[cmd->obj.to]; 1268 if (!mod_timer(timer, jiffies + timeout)) 1269 sctp_association_hold(asoc); 1270 break; 1271 1272 case SCTP_CMD_TIMER_STOP: 1273 timer = &asoc->timers[cmd->obj.to]; 1274 if (timer_pending(timer) && del_timer(timer)) 1275 sctp_association_put(asoc); 1276 break; 1277 1278 case SCTP_CMD_INIT_CHOOSE_TRANSPORT: 1279 chunk = cmd->obj.ptr; 1280 t = sctp_assoc_choose_init_transport(asoc); 1281 asoc->init_last_sent_to = t; 1282 chunk->transport = t; 1283 t->init_sent_count++; 1284 break; 1285 1286 case SCTP_CMD_INIT_RESTART: 1287 /* Do the needed accounting and updates 1288 * associated with restarting an initialization 1289 * timer. Only multiply the timeout by two if 1290 * all transports have been tried at the current 1291 * timeout. 1292 */ 1293 t = asoc->init_last_sent_to; 1294 asoc->init_err_counter++; 1295 1296 if (t->init_sent_count > (asoc->init_cycle + 1)) { 1297 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] *= 2; 1298 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] > 1299 asoc->max_init_timeo) { 1300 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 1301 asoc->max_init_timeo; 1302 } 1303 asoc->init_cycle++; 1304 SCTP_DEBUG_PRINTK( 1305 "T1 INIT Timeout adjustment" 1306 " init_err_counter: %d" 1307 " cycle: %d" 1308 " timeout: %ld\n", 1309 asoc->init_err_counter, 1310 asoc->init_cycle, 1311 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT]); 1312 } 1313 1314 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 1315 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); 1316 break; 1317 1318 case SCTP_CMD_COOKIEECHO_RESTART: 1319 /* Do the needed accounting and updates 1320 * associated with restarting an initialization 1321 * timer. Only multiply the timeout by two if 1322 * all transports have been tried at the current 1323 * timeout. 1324 */ 1325 asoc->init_err_counter++; 1326 1327 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] *= 2; 1328 if (asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] > 1329 asoc->max_init_timeo) { 1330 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 1331 asoc->max_init_timeo; 1332 } 1333 SCTP_DEBUG_PRINTK( 1334 "T1 COOKIE Timeout adjustment" 1335 " init_err_counter: %d" 1336 " timeout: %ld\n", 1337 asoc->init_err_counter, 1338 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE]); 1339 1340 /* If we've sent any data bundled with 1341 * COOKIE-ECHO we need to resend. 1342 */ 1343 list_for_each(pos, &asoc->peer.transport_addr_list) { 1344 t = list_entry(pos, struct sctp_transport, 1345 transports); 1346 sctp_retransmit_mark(&asoc->outqueue, t, 0); 1347 } 1348 1349 sctp_add_cmd_sf(commands, 1350 SCTP_CMD_TIMER_RESTART, 1351 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); 1352 break; 1353 1354 case SCTP_CMD_INIT_FAILED: 1355 sctp_cmd_init_failed(commands, asoc, cmd->obj.u32); 1356 break; 1357 1358 case SCTP_CMD_ASSOC_FAILED: 1359 sctp_cmd_assoc_failed(commands, asoc, event_type, 1360 subtype, chunk, cmd->obj.u32); 1361 break; 1362 1363 case SCTP_CMD_INIT_COUNTER_INC: 1364 asoc->init_err_counter++; 1365 break; 1366 1367 case SCTP_CMD_INIT_COUNTER_RESET: 1368 asoc->init_err_counter = 0; 1369 asoc->init_cycle = 0; 1370 break; 1371 1372 case SCTP_CMD_REPORT_DUP: 1373 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, 1374 cmd->obj.u32); 1375 break; 1376 1377 case SCTP_CMD_REPORT_BAD_TAG: 1378 SCTP_DEBUG_PRINTK("vtag mismatch!\n"); 1379 break; 1380 1381 case SCTP_CMD_STRIKE: 1382 /* Mark one strike against a transport. */ 1383 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport); 1384 break; 1385 1386 case SCTP_CMD_TRANSPORT_RESET: 1387 t = cmd->obj.transport; 1388 sctp_cmd_transport_reset(commands, asoc, t); 1389 break; 1390 1391 case SCTP_CMD_TRANSPORT_ON: 1392 t = cmd->obj.transport; 1393 sctp_cmd_transport_on(commands, asoc, t, chunk); 1394 break; 1395 1396 case SCTP_CMD_HB_TIMERS_START: 1397 sctp_cmd_hb_timers_start(commands, asoc); 1398 break; 1399 1400 case SCTP_CMD_HB_TIMER_UPDATE: 1401 t = cmd->obj.transport; 1402 sctp_cmd_hb_timer_update(commands, asoc, t); 1403 break; 1404 1405 case SCTP_CMD_HB_TIMERS_STOP: 1406 sctp_cmd_hb_timers_stop(commands, asoc); 1407 break; 1408 1409 case SCTP_CMD_REPORT_ERROR: 1410 error = cmd->obj.error; 1411 break; 1412 1413 case SCTP_CMD_PROCESS_CTSN: 1414 /* Dummy up a SACK for processing. */ 1415 sackh.cum_tsn_ack = cmd->obj.u32; 1416 sackh.a_rwnd = 0; 1417 sackh.num_gap_ack_blocks = 0; 1418 sackh.num_dup_tsns = 0; 1419 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, 1420 SCTP_SACKH(&sackh)); 1421 break; 1422 1423 case SCTP_CMD_DISCARD_PACKET: 1424 /* We need to discard the whole packet. */ 1425 chunk->pdiscard = 1; 1426 break; 1427 1428 case SCTP_CMD_RTO_PENDING: 1429 t = cmd->obj.transport; 1430 t->rto_pending = 1; 1431 break; 1432 1433 case SCTP_CMD_PART_DELIVER: 1434 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr, 1435 GFP_ATOMIC); 1436 break; 1437 1438 case SCTP_CMD_RENEGE: 1439 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, 1440 GFP_ATOMIC); 1441 break; 1442 1443 case SCTP_CMD_SETUP_T4: 1444 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); 1445 break; 1446 1447 case SCTP_CMD_PROCESS_OPERR: 1448 sctp_cmd_process_operr(commands, asoc, chunk); 1449 break; 1450 case SCTP_CMD_CLEAR_INIT_TAG: 1451 asoc->peer.i.init_tag = 0; 1452 break; 1453 case SCTP_CMD_DEL_NON_PRIMARY: 1454 sctp_cmd_del_non_primary(asoc); 1455 break; 1456 case SCTP_CMD_T3_RTX_TIMERS_STOP: 1457 sctp_cmd_t3_rtx_timers_stop(commands, asoc); 1458 break; 1459 case SCTP_CMD_FORCE_PRIM_RETRAN: 1460 t = asoc->peer.retran_path; 1461 asoc->peer.retran_path = asoc->peer.primary_path; 1462 error = sctp_outq_uncork(&asoc->outqueue); 1463 local_cork = 0; 1464 asoc->peer.retran_path = t; 1465 break; 1466 case SCTP_CMD_SET_SK_ERR: 1467 sctp_cmd_set_sk_err(asoc, cmd->obj.error); 1468 break; 1469 default: 1470 printk(KERN_WARNING "Impossible command: %u, %p\n", 1471 cmd->verb, cmd->obj.ptr); 1472 break; 1473 }; 1474 if (error) 1475 break; 1476 } 1477 1478 out: 1479 if (local_cork) 1480 sctp_outq_uncork(&asoc->outqueue); 1481 return error; 1482 nomem: 1483 error = -ENOMEM; 1484 goto out; 1485 } 1486 1487