1 /* SCTP kernel 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 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 * This SCTP 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 * This SCTP 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 asoc->peer.sack_cnt++; 194 195 /* Set the SACK delay timeout based on the 196 * SACK delay for the last transport 197 * data was received from, or the default 198 * for the association. 199 */ 200 if (trans) { 201 /* We will need a SACK for the next packet. */ 202 if (asoc->peer.sack_cnt >= trans->sackfreq - 1) 203 asoc->peer.sack_needed = 1; 204 205 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 206 trans->sackdelay; 207 } else { 208 /* We will need a SACK for the next packet. */ 209 if (asoc->peer.sack_cnt >= asoc->sackfreq - 1) 210 asoc->peer.sack_needed = 1; 211 212 asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = 213 asoc->sackdelay; 214 } 215 216 /* Restart the SACK timer. */ 217 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 218 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 219 } else { 220 if (asoc->a_rwnd > asoc->rwnd) 221 asoc->a_rwnd = asoc->rwnd; 222 sack = sctp_make_sack(asoc); 223 if (!sack) 224 goto nomem; 225 226 asoc->peer.sack_needed = 0; 227 asoc->peer.sack_cnt = 0; 228 229 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(sack)); 230 231 /* Stop the SACK timer. */ 232 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP, 233 SCTP_TO(SCTP_EVENT_TIMEOUT_SACK)); 234 } 235 236 return error; 237 nomem: 238 error = -ENOMEM; 239 return error; 240 } 241 242 /* When the T3-RTX timer expires, it calls this function to create the 243 * relevant state machine event. 244 */ 245 void sctp_generate_t3_rtx_event(unsigned long peer) 246 { 247 int error; 248 struct sctp_transport *transport = (struct sctp_transport *) peer; 249 struct sctp_association *asoc = transport->asoc; 250 251 /* Check whether a task is in the sock. */ 252 253 sctp_bh_lock_sock(asoc->base.sk); 254 if (sock_owned_by_user(asoc->base.sk)) { 255 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__); 256 257 /* Try again later. */ 258 if (!mod_timer(&transport->T3_rtx_timer, jiffies + (HZ/20))) 259 sctp_transport_hold(transport); 260 goto out_unlock; 261 } 262 263 /* Is this transport really dead and just waiting around for 264 * the timer to let go of the reference? 265 */ 266 if (transport->dead) 267 goto out_unlock; 268 269 /* Run through the state machine. */ 270 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 271 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_T3_RTX), 272 asoc->state, 273 asoc->ep, asoc, 274 transport, GFP_ATOMIC); 275 276 if (error) 277 asoc->base.sk->sk_err = -error; 278 279 out_unlock: 280 sctp_bh_unlock_sock(asoc->base.sk); 281 sctp_transport_put(transport); 282 } 283 284 /* This is a sa interface for producing timeout events. It works 285 * for timeouts which use the association as their parameter. 286 */ 287 static void sctp_generate_timeout_event(struct sctp_association *asoc, 288 sctp_event_timeout_t timeout_type) 289 { 290 int error = 0; 291 292 sctp_bh_lock_sock(asoc->base.sk); 293 if (sock_owned_by_user(asoc->base.sk)) { 294 SCTP_DEBUG_PRINTK("%s:Sock is busy: timer %d\n", 295 __func__, 296 timeout_type); 297 298 /* Try again later. */ 299 if (!mod_timer(&asoc->timers[timeout_type], jiffies + (HZ/20))) 300 sctp_association_hold(asoc); 301 goto out_unlock; 302 } 303 304 /* Is this association really dead and just waiting around for 305 * the timer to let go of the reference? 306 */ 307 if (asoc->base.dead) 308 goto out_unlock; 309 310 /* Run through the state machine. */ 311 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 312 SCTP_ST_TIMEOUT(timeout_type), 313 asoc->state, asoc->ep, asoc, 314 (void *)timeout_type, GFP_ATOMIC); 315 316 if (error) 317 asoc->base.sk->sk_err = -error; 318 319 out_unlock: 320 sctp_bh_unlock_sock(asoc->base.sk); 321 sctp_association_put(asoc); 322 } 323 324 static void sctp_generate_t1_cookie_event(unsigned long data) 325 { 326 struct sctp_association *asoc = (struct sctp_association *) data; 327 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_COOKIE); 328 } 329 330 static void sctp_generate_t1_init_event(unsigned long data) 331 { 332 struct sctp_association *asoc = (struct sctp_association *) data; 333 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T1_INIT); 334 } 335 336 static void sctp_generate_t2_shutdown_event(unsigned long data) 337 { 338 struct sctp_association *asoc = (struct sctp_association *) data; 339 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T2_SHUTDOWN); 340 } 341 342 static void sctp_generate_t4_rto_event(unsigned long data) 343 { 344 struct sctp_association *asoc = (struct sctp_association *) data; 345 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_T4_RTO); 346 } 347 348 static void sctp_generate_t5_shutdown_guard_event(unsigned long data) 349 { 350 struct sctp_association *asoc = (struct sctp_association *)data; 351 sctp_generate_timeout_event(asoc, 352 SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD); 353 354 } /* sctp_generate_t5_shutdown_guard_event() */ 355 356 static void sctp_generate_autoclose_event(unsigned long data) 357 { 358 struct sctp_association *asoc = (struct sctp_association *) data; 359 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_AUTOCLOSE); 360 } 361 362 /* Generate a heart beat event. If the sock is busy, reschedule. Make 363 * sure that the transport is still valid. 364 */ 365 void sctp_generate_heartbeat_event(unsigned long data) 366 { 367 int error = 0; 368 struct sctp_transport *transport = (struct sctp_transport *) data; 369 struct sctp_association *asoc = transport->asoc; 370 371 sctp_bh_lock_sock(asoc->base.sk); 372 if (sock_owned_by_user(asoc->base.sk)) { 373 SCTP_DEBUG_PRINTK("%s:Sock is busy.\n", __func__); 374 375 /* Try again later. */ 376 if (!mod_timer(&transport->hb_timer, jiffies + (HZ/20))) 377 sctp_transport_hold(transport); 378 goto out_unlock; 379 } 380 381 /* Is this structure just waiting around for us to actually 382 * get destroyed? 383 */ 384 if (transport->dead) 385 goto out_unlock; 386 387 error = sctp_do_sm(SCTP_EVENT_T_TIMEOUT, 388 SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_HEARTBEAT), 389 asoc->state, asoc->ep, asoc, 390 transport, GFP_ATOMIC); 391 392 if (error) 393 asoc->base.sk->sk_err = -error; 394 395 out_unlock: 396 sctp_bh_unlock_sock(asoc->base.sk); 397 sctp_transport_put(transport); 398 } 399 400 /* Inject a SACK Timeout event into the state machine. */ 401 static void sctp_generate_sack_event(unsigned long data) 402 { 403 struct sctp_association *asoc = (struct sctp_association *) data; 404 sctp_generate_timeout_event(asoc, SCTP_EVENT_TIMEOUT_SACK); 405 } 406 407 sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = { 408 NULL, 409 sctp_generate_t1_cookie_event, 410 sctp_generate_t1_init_event, 411 sctp_generate_t2_shutdown_event, 412 NULL, 413 sctp_generate_t4_rto_event, 414 sctp_generate_t5_shutdown_guard_event, 415 NULL, 416 sctp_generate_sack_event, 417 sctp_generate_autoclose_event, 418 }; 419 420 421 /* RFC 2960 8.2 Path Failure Detection 422 * 423 * When its peer endpoint is multi-homed, an endpoint should keep a 424 * error counter for each of the destination transport addresses of the 425 * peer endpoint. 426 * 427 * Each time the T3-rtx timer expires on any address, or when a 428 * HEARTBEAT sent to an idle address is not acknowledged within a RTO, 429 * the error counter of that destination address will be incremented. 430 * When the value in the error counter exceeds the protocol parameter 431 * 'Path.Max.Retrans' of that destination address, the endpoint should 432 * mark the destination transport address as inactive, and a 433 * notification SHOULD be sent to the upper layer. 434 * 435 */ 436 static void sctp_do_8_2_transport_strike(struct sctp_association *asoc, 437 struct sctp_transport *transport, 438 int is_hb) 439 { 440 /* The check for association's overall error counter exceeding the 441 * threshold is done in the state function. 442 */ 443 /* When probing UNCONFIRMED addresses, the association overall 444 * error count is NOT incremented 445 */ 446 if (transport->state != SCTP_UNCONFIRMED) 447 asoc->overall_error_count++; 448 449 if (transport->state != SCTP_INACTIVE && 450 (transport->error_count++ >= transport->pathmaxrxt)) { 451 SCTP_DEBUG_PRINTK_IPADDR("transport_strike:association %p", 452 " transport IP: port:%d failed.\n", 453 asoc, 454 (&transport->ipaddr), 455 ntohs(transport->ipaddr.v4.sin_port)); 456 sctp_assoc_control_transport(asoc, transport, 457 SCTP_TRANSPORT_DOWN, 458 SCTP_FAILED_THRESHOLD); 459 } 460 461 /* E2) For the destination address for which the timer 462 * expires, set RTO <- RTO * 2 ("back off the timer"). The 463 * maximum value discussed in rule C7 above (RTO.max) may be 464 * used to provide an upper bound to this doubling operation. 465 * 466 * Special Case: the first HB doesn't trigger exponential backoff. 467 * The first unacknowleged HB triggers it. We do this with a flag 468 * that indicates that we have an outstanding HB. 469 */ 470 if (!is_hb || transport->hb_sent) { 471 transport->last_rto = transport->rto; 472 transport->rto = min((transport->rto * 2), transport->asoc->rto_max); 473 } 474 } 475 476 /* Worker routine to handle INIT command failure. */ 477 static void sctp_cmd_init_failed(sctp_cmd_seq_t *commands, 478 struct sctp_association *asoc, 479 unsigned error) 480 { 481 struct sctp_ulpevent *event; 482 483 event = sctp_ulpevent_make_assoc_change(asoc,0, SCTP_CANT_STR_ASSOC, 484 (__u16)error, 0, 0, NULL, 485 GFP_ATOMIC); 486 487 if (event) 488 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 489 SCTP_ULPEVENT(event)); 490 491 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 492 SCTP_STATE(SCTP_STATE_CLOSED)); 493 494 /* SEND_FAILED sent later when cleaning up the association. */ 495 asoc->outqueue.error = error; 496 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 497 } 498 499 /* Worker routine to handle SCTP_CMD_ASSOC_FAILED. */ 500 static void sctp_cmd_assoc_failed(sctp_cmd_seq_t *commands, 501 struct sctp_association *asoc, 502 sctp_event_t event_type, 503 sctp_subtype_t subtype, 504 struct sctp_chunk *chunk, 505 unsigned error) 506 { 507 struct sctp_ulpevent *event; 508 509 /* Cancel any partial delivery in progress. */ 510 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 511 512 if (event_type == SCTP_EVENT_T_CHUNK && subtype.chunk == SCTP_CID_ABORT) 513 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 514 (__u16)error, 0, 0, chunk, 515 GFP_ATOMIC); 516 else 517 event = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_COMM_LOST, 518 (__u16)error, 0, 0, NULL, 519 GFP_ATOMIC); 520 if (event) 521 sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, 522 SCTP_ULPEVENT(event)); 523 524 sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, 525 SCTP_STATE(SCTP_STATE_CLOSED)); 526 527 /* SEND_FAILED sent later when cleaning up the association. */ 528 asoc->outqueue.error = error; 529 sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL()); 530 } 531 532 /* Process an init chunk (may be real INIT/INIT-ACK or an embedded INIT 533 * inside the cookie. In reality, this is only used for INIT-ACK processing 534 * since all other cases use "temporary" associations and can do all 535 * their work in statefuns directly. 536 */ 537 static int sctp_cmd_process_init(sctp_cmd_seq_t *commands, 538 struct sctp_association *asoc, 539 struct sctp_chunk *chunk, 540 sctp_init_chunk_t *peer_init, 541 gfp_t gfp) 542 { 543 int error; 544 545 /* We only process the init as a sideeffect in a single 546 * case. This is when we process the INIT-ACK. If we 547 * fail during INIT processing (due to malloc problems), 548 * just return the error and stop processing the stack. 549 */ 550 if (!sctp_process_init(asoc, chunk->chunk_hdr->type, 551 sctp_source(chunk), peer_init, gfp)) 552 error = -ENOMEM; 553 else 554 error = 0; 555 556 return error; 557 } 558 559 /* Helper function to break out starting up of heartbeat timers. */ 560 static void sctp_cmd_hb_timers_start(sctp_cmd_seq_t *cmds, 561 struct sctp_association *asoc) 562 { 563 struct sctp_transport *t; 564 565 /* Start a heartbeat timer for each transport on the association. 566 * hold a reference on the transport to make sure none of 567 * the needed data structures go away. 568 */ 569 list_for_each_entry(t, &asoc->peer.transport_addr_list, transports) { 570 571 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 572 sctp_transport_hold(t); 573 } 574 } 575 576 static void sctp_cmd_hb_timers_stop(sctp_cmd_seq_t *cmds, 577 struct sctp_association *asoc) 578 { 579 struct sctp_transport *t; 580 581 /* Stop all heartbeat timers. */ 582 583 list_for_each_entry(t, &asoc->peer.transport_addr_list, 584 transports) { 585 if (del_timer(&t->hb_timer)) 586 sctp_transport_put(t); 587 } 588 } 589 590 /* Helper function to stop any pending T3-RTX timers */ 591 static void sctp_cmd_t3_rtx_timers_stop(sctp_cmd_seq_t *cmds, 592 struct sctp_association *asoc) 593 { 594 struct sctp_transport *t; 595 596 list_for_each_entry(t, &asoc->peer.transport_addr_list, 597 transports) { 598 if (timer_pending(&t->T3_rtx_timer) && 599 del_timer(&t->T3_rtx_timer)) { 600 sctp_transport_put(t); 601 } 602 } 603 } 604 605 606 /* Helper function to update the heartbeat timer. */ 607 static void sctp_cmd_hb_timer_update(sctp_cmd_seq_t *cmds, 608 struct sctp_transport *t) 609 { 610 /* Update the heartbeat timer. */ 611 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 612 sctp_transport_hold(t); 613 } 614 615 /* Helper function to handle the reception of an HEARTBEAT ACK. */ 616 static void sctp_cmd_transport_on(sctp_cmd_seq_t *cmds, 617 struct sctp_association *asoc, 618 struct sctp_transport *t, 619 struct sctp_chunk *chunk) 620 { 621 sctp_sender_hb_info_t *hbinfo; 622 623 /* 8.3 Upon the receipt of the HEARTBEAT ACK, the sender of the 624 * HEARTBEAT should clear the error counter of the destination 625 * transport address to which the HEARTBEAT was sent. 626 * The association's overall error count is also cleared. 627 */ 628 t->error_count = 0; 629 t->asoc->overall_error_count = 0; 630 631 /* Clear the hb_sent flag to signal that we had a good 632 * acknowledgement. 633 */ 634 t->hb_sent = 0; 635 636 /* Mark the destination transport address as active if it is not so 637 * marked. 638 */ 639 if ((t->state == SCTP_INACTIVE) || (t->state == SCTP_UNCONFIRMED)) 640 sctp_assoc_control_transport(asoc, t, SCTP_TRANSPORT_UP, 641 SCTP_HEARTBEAT_SUCCESS); 642 643 /* The receiver of the HEARTBEAT ACK should also perform an 644 * RTT measurement for that destination transport address 645 * using the time value carried in the HEARTBEAT ACK chunk. 646 * If the transport's rto_pending variable has been cleared, 647 * it was most likely due to a retransmit. However, we want 648 * to re-enable it to properly update the rto. 649 */ 650 if (t->rto_pending == 0) 651 t->rto_pending = 1; 652 653 hbinfo = (sctp_sender_hb_info_t *) chunk->skb->data; 654 sctp_transport_update_rto(t, (jiffies - hbinfo->sent_at)); 655 656 /* Update the heartbeat timer. */ 657 if (!mod_timer(&t->hb_timer, sctp_transport_timeout(t))) 658 sctp_transport_hold(t); 659 } 660 661 662 /* Helper function to process the process SACK command. */ 663 static int sctp_cmd_process_sack(sctp_cmd_seq_t *cmds, 664 struct sctp_association *asoc, 665 struct sctp_sackhdr *sackh) 666 { 667 int err = 0; 668 669 if (sctp_outq_sack(&asoc->outqueue, sackh)) { 670 /* There are no more TSNs awaiting SACK. */ 671 err = sctp_do_sm(SCTP_EVENT_T_OTHER, 672 SCTP_ST_OTHER(SCTP_EVENT_NO_PENDING_TSN), 673 asoc->state, asoc->ep, asoc, NULL, 674 GFP_ATOMIC); 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_alter_transport(asoc, 690 asoc->shutdown_last_sent_to); 691 asoc->shutdown_last_sent_to = t; 692 asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = t->rto; 693 chunk->transport = t; 694 } 695 696 /* Helper function to change the state of an association. */ 697 static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, 698 struct sctp_association *asoc, 699 sctp_state_t state) 700 { 701 struct sock *sk = asoc->base.sk; 702 703 asoc->state = state; 704 705 SCTP_DEBUG_PRINTK("sctp_cmd_new_state: asoc %p[%s]\n", 706 asoc, sctp_state_tbl[state]); 707 708 if (sctp_style(sk, TCP)) { 709 /* Change the sk->sk_state of a TCP-style socket that has 710 * sucessfully completed a connect() call. 711 */ 712 if (sctp_state(asoc, ESTABLISHED) && sctp_sstate(sk, CLOSED)) 713 sk->sk_state = SCTP_SS_ESTABLISHED; 714 715 /* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */ 716 if (sctp_state(asoc, SHUTDOWN_RECEIVED) && 717 sctp_sstate(sk, ESTABLISHED)) 718 sk->sk_shutdown |= RCV_SHUTDOWN; 719 } 720 721 if (sctp_state(asoc, COOKIE_WAIT)) { 722 /* Reset init timeouts since they may have been 723 * increased due to timer expirations. 724 */ 725 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = 726 asoc->rto_initial; 727 asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = 728 asoc->rto_initial; 729 } 730 731 if (sctp_state(asoc, ESTABLISHED) || 732 sctp_state(asoc, CLOSED) || 733 sctp_state(asoc, SHUTDOWN_RECEIVED)) { 734 /* Wake up any processes waiting in the asoc's wait queue in 735 * sctp_wait_for_connect() or sctp_wait_for_sndbuf(). 736 */ 737 if (waitqueue_active(&asoc->wait)) 738 wake_up_interruptible(&asoc->wait); 739 740 /* Wake up any processes waiting in the sk's sleep queue of 741 * a TCP-style or UDP-style peeled-off socket in 742 * sctp_wait_for_accept() or sctp_wait_for_packet(). 743 * For a UDP-style socket, the waiters are woken up by the 744 * notifications. 745 */ 746 if (!sctp_style(sk, UDP)) 747 sk->sk_state_change(sk); 748 } 749 } 750 751 /* Helper function to delete an association. */ 752 static void sctp_cmd_delete_tcb(sctp_cmd_seq_t *cmds, 753 struct sctp_association *asoc) 754 { 755 struct sock *sk = asoc->base.sk; 756 757 /* If it is a non-temporary association belonging to a TCP-style 758 * listening socket that is not closed, do not free it so that accept() 759 * can pick it up later. 760 */ 761 if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING) && 762 (!asoc->temp) && (sk->sk_shutdown != SHUTDOWN_MASK)) 763 return; 764 765 sctp_unhash_established(asoc); 766 sctp_association_free(asoc); 767 } 768 769 /* 770 * ADDIP Section 4.1 ASCONF Chunk Procedures 771 * A4) Start a T-4 RTO timer, using the RTO value of the selected 772 * destination address (we use active path instead of primary path just 773 * because primary path may be inactive. 774 */ 775 static void sctp_cmd_setup_t4(sctp_cmd_seq_t *cmds, 776 struct sctp_association *asoc, 777 struct sctp_chunk *chunk) 778 { 779 struct sctp_transport *t; 780 781 t = sctp_assoc_choose_alter_transport(asoc, chunk->transport); 782 asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = t->rto; 783 chunk->transport = t; 784 } 785 786 /* Process an incoming Operation Error Chunk. */ 787 static void sctp_cmd_process_operr(sctp_cmd_seq_t *cmds, 788 struct sctp_association *asoc, 789 struct sctp_chunk *chunk) 790 { 791 struct sctp_errhdr *err_hdr; 792 struct sctp_ulpevent *ev; 793 794 while (chunk->chunk_end > chunk->skb->data) { 795 err_hdr = (struct sctp_errhdr *)(chunk->skb->data); 796 797 ev = sctp_ulpevent_make_remote_error(asoc, chunk, 0, 798 GFP_ATOMIC); 799 if (!ev) 800 return; 801 802 sctp_ulpq_tail_event(&asoc->ulpq, ev); 803 804 switch (err_hdr->cause) { 805 case SCTP_ERROR_UNKNOWN_CHUNK: 806 { 807 sctp_chunkhdr_t *unk_chunk_hdr; 808 809 unk_chunk_hdr = (sctp_chunkhdr_t *)err_hdr->variable; 810 switch (unk_chunk_hdr->type) { 811 /* ADDIP 4.1 A9) If the peer responds to an ASCONF with 812 * an ERROR chunk reporting that it did not recognized 813 * the ASCONF chunk type, the sender of the ASCONF MUST 814 * NOT send any further ASCONF chunks and MUST stop its 815 * T-4 timer. 816 */ 817 case SCTP_CID_ASCONF: 818 if (asoc->peer.asconf_capable == 0) 819 break; 820 821 asoc->peer.asconf_capable = 0; 822 sctp_add_cmd_sf(cmds, SCTP_CMD_TIMER_STOP, 823 SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); 824 break; 825 default: 826 break; 827 } 828 break; 829 } 830 default: 831 break; 832 } 833 } 834 } 835 836 /* Process variable FWDTSN chunk information. */ 837 static void sctp_cmd_process_fwdtsn(struct sctp_ulpq *ulpq, 838 struct sctp_chunk *chunk) 839 { 840 struct sctp_fwdtsn_skip *skip; 841 /* Walk through all the skipped SSNs */ 842 sctp_walk_fwdtsn(skip, chunk) { 843 sctp_ulpq_skip(ulpq, ntohs(skip->stream), ntohs(skip->ssn)); 844 } 845 846 return; 847 } 848 849 /* Helper function to remove the association non-primary peer 850 * transports. 851 */ 852 static void sctp_cmd_del_non_primary(struct sctp_association *asoc) 853 { 854 struct sctp_transport *t; 855 struct list_head *pos; 856 struct list_head *temp; 857 858 list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { 859 t = list_entry(pos, struct sctp_transport, transports); 860 if (!sctp_cmp_addr_exact(&t->ipaddr, 861 &asoc->peer.primary_addr)) { 862 sctp_assoc_del_peer(asoc, &t->ipaddr); 863 } 864 } 865 866 return; 867 } 868 869 /* Helper function to set sk_err on a 1-1 style socket. */ 870 static void sctp_cmd_set_sk_err(struct sctp_association *asoc, int error) 871 { 872 struct sock *sk = asoc->base.sk; 873 874 if (!sctp_style(sk, UDP)) 875 sk->sk_err = error; 876 } 877 878 /* Helper function to generate an association change event */ 879 static void sctp_cmd_assoc_change(sctp_cmd_seq_t *commands, 880 struct sctp_association *asoc, 881 u8 state) 882 { 883 struct sctp_ulpevent *ev; 884 885 ev = sctp_ulpevent_make_assoc_change(asoc, 0, state, 0, 886 asoc->c.sinit_num_ostreams, 887 asoc->c.sinit_max_instreams, 888 NULL, GFP_ATOMIC); 889 if (ev) 890 sctp_ulpq_tail_event(&asoc->ulpq, ev); 891 } 892 893 /* Helper function to generate an adaptation indication event */ 894 static void sctp_cmd_adaptation_ind(sctp_cmd_seq_t *commands, 895 struct sctp_association *asoc) 896 { 897 struct sctp_ulpevent *ev; 898 899 ev = sctp_ulpevent_make_adaptation_indication(asoc, GFP_ATOMIC); 900 901 if (ev) 902 sctp_ulpq_tail_event(&asoc->ulpq, ev); 903 } 904 905 906 static void sctp_cmd_t1_timer_update(struct sctp_association *asoc, 907 sctp_event_timeout_t timer, 908 char *name) 909 { 910 struct sctp_transport *t; 911 912 t = asoc->init_last_sent_to; 913 asoc->init_err_counter++; 914 915 if (t->init_sent_count > (asoc->init_cycle + 1)) { 916 asoc->timeouts[timer] *= 2; 917 if (asoc->timeouts[timer] > asoc->max_init_timeo) { 918 asoc->timeouts[timer] = asoc->max_init_timeo; 919 } 920 asoc->init_cycle++; 921 SCTP_DEBUG_PRINTK( 922 "T1 %s Timeout adjustment" 923 " init_err_counter: %d" 924 " cycle: %d" 925 " timeout: %ld\n", 926 name, 927 asoc->init_err_counter, 928 asoc->init_cycle, 929 asoc->timeouts[timer]); 930 } 931 932 } 933 934 /* These three macros allow us to pull the debugging code out of the 935 * main flow of sctp_do_sm() to keep attention focused on the real 936 * functionality there. 937 */ 938 #define DEBUG_PRE \ 939 SCTP_DEBUG_PRINTK("sctp_do_sm prefn: " \ 940 "ep %p, %s, %s, asoc %p[%s], %s\n", \ 941 ep, sctp_evttype_tbl[event_type], \ 942 (*debug_fn)(subtype), asoc, \ 943 sctp_state_tbl[state], state_fn->name) 944 945 #define DEBUG_POST \ 946 SCTP_DEBUG_PRINTK("sctp_do_sm postfn: " \ 947 "asoc %p, status: %s\n", \ 948 asoc, sctp_status_tbl[status]) 949 950 #define DEBUG_POST_SFX \ 951 SCTP_DEBUG_PRINTK("sctp_do_sm post sfx: error %d, asoc %p[%s]\n", \ 952 error, asoc, \ 953 sctp_state_tbl[(asoc && sctp_id2assoc(ep->base.sk, \ 954 sctp_assoc2id(asoc)))?asoc->state:SCTP_STATE_CLOSED]) 955 956 /* 957 * This is the master state machine processing function. 958 * 959 * If you want to understand all of lksctp, this is a 960 * good place to start. 961 */ 962 int sctp_do_sm(sctp_event_t event_type, sctp_subtype_t subtype, 963 sctp_state_t state, 964 struct sctp_endpoint *ep, 965 struct sctp_association *asoc, 966 void *event_arg, 967 gfp_t gfp) 968 { 969 sctp_cmd_seq_t commands; 970 const sctp_sm_table_entry_t *state_fn; 971 sctp_disposition_t status; 972 int error = 0; 973 typedef const char *(printfn_t)(sctp_subtype_t); 974 975 static printfn_t *table[] = { 976 NULL, sctp_cname, sctp_tname, sctp_oname, sctp_pname, 977 }; 978 printfn_t *debug_fn __attribute__ ((unused)) = table[event_type]; 979 980 /* Look up the state function, run it, and then process the 981 * side effects. These three steps are the heart of lksctp. 982 */ 983 state_fn = sctp_sm_lookup_event(event_type, state, subtype); 984 985 sctp_init_cmd_seq(&commands); 986 987 DEBUG_PRE; 988 status = (*state_fn->fn)(ep, asoc, subtype, event_arg, &commands); 989 DEBUG_POST; 990 991 error = sctp_side_effects(event_type, subtype, state, 992 ep, asoc, event_arg, status, 993 &commands, gfp); 994 DEBUG_POST_SFX; 995 996 return error; 997 } 998 999 #undef DEBUG_PRE 1000 #undef DEBUG_POST 1001 1002 /***************************************************************** 1003 * This the master state function side effect processing function. 1004 *****************************************************************/ 1005 static int sctp_side_effects(sctp_event_t event_type, 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; 1015 1016 /* FIXME - Most of the dispositions left today would be categorized 1017 * as "exceptional" dispositions. For those dispositions, it 1018 * may not be proper to run through any of the commands at all. 1019 * For example, the command interpreter might be run only with 1020 * disposition SCTP_DISPOSITION_CONSUME. 1021 */ 1022 if (0 != (error = sctp_cmd_interpreter(event_type, subtype, state, 1023 ep, asoc, 1024 event_arg, status, 1025 commands, gfp))) 1026 goto bail; 1027 1028 switch (status) { 1029 case SCTP_DISPOSITION_DISCARD: 1030 SCTP_DEBUG_PRINTK("Ignored sctp protocol event - state %d, " 1031 "event_type %d, event_id %d\n", 1032 state, event_type, subtype.chunk); 1033 break; 1034 1035 case SCTP_DISPOSITION_NOMEM: 1036 /* We ran out of memory, so we need to discard this 1037 * packet. 1038 */ 1039 /* BUG--we should now recover some memory, probably by 1040 * reneging... 1041 */ 1042 error = -ENOMEM; 1043 break; 1044 1045 case SCTP_DISPOSITION_DELETE_TCB: 1046 /* This should now be a command. */ 1047 break; 1048 1049 case SCTP_DISPOSITION_CONSUME: 1050 case SCTP_DISPOSITION_ABORT: 1051 /* 1052 * We should no longer have much work to do here as the 1053 * real work has been done as explicit commands above. 1054 */ 1055 break; 1056 1057 case SCTP_DISPOSITION_VIOLATION: 1058 if (net_ratelimit()) 1059 printk(KERN_ERR "sctp protocol violation state %d " 1060 "chunkid %d\n", state, subtype.chunk); 1061 break; 1062 1063 case SCTP_DISPOSITION_NOT_IMPL: 1064 printk(KERN_WARNING "sctp unimplemented feature in state %d, " 1065 "event_type %d, event_id %d\n", 1066 state, event_type, subtype.chunk); 1067 break; 1068 1069 case SCTP_DISPOSITION_BUG: 1070 printk(KERN_ERR "sctp bug in state %d, " 1071 "event_type %d, event_id %d\n", 1072 state, event_type, subtype.chunk); 1073 BUG(); 1074 break; 1075 1076 default: 1077 printk(KERN_ERR "sctp impossible disposition %d " 1078 "in state %d, event_type %d, event_id %d\n", 1079 status, state, event_type, subtype.chunk); 1080 BUG(); 1081 break; 1082 } 1083 1084 bail: 1085 return error; 1086 } 1087 1088 /******************************************************************** 1089 * 2nd Level Abstractions 1090 ********************************************************************/ 1091 1092 /* This is the side-effect interpreter. */ 1093 static int sctp_cmd_interpreter(sctp_event_t event_type, 1094 sctp_subtype_t subtype, 1095 sctp_state_t state, 1096 struct sctp_endpoint *ep, 1097 struct sctp_association *asoc, 1098 void *event_arg, 1099 sctp_disposition_t status, 1100 sctp_cmd_seq_t *commands, 1101 gfp_t gfp) 1102 { 1103 int error = 0; 1104 int force; 1105 sctp_cmd_t *cmd; 1106 struct sctp_chunk *new_obj; 1107 struct sctp_chunk *chunk = NULL; 1108 struct sctp_packet *packet; 1109 struct timer_list *timer; 1110 unsigned long timeout; 1111 struct sctp_transport *t; 1112 struct sctp_sackhdr sackh; 1113 int local_cork = 0; 1114 1115 if (SCTP_EVENT_T_TIMEOUT != event_type) 1116 chunk = (struct sctp_chunk *) event_arg; 1117 1118 /* Note: This whole file is a huge candidate for rework. 1119 * For example, each command could either have its own handler, so 1120 * the loop would look like: 1121 * while (cmds) 1122 * cmd->handle(x, y, z) 1123 * --jgrimm 1124 */ 1125 while (NULL != (cmd = sctp_next_cmd(commands))) { 1126 switch (cmd->verb) { 1127 case SCTP_CMD_NOP: 1128 /* Do nothing. */ 1129 break; 1130 1131 case SCTP_CMD_NEW_ASOC: 1132 /* Register a new association. */ 1133 if (local_cork) { 1134 sctp_outq_uncork(&asoc->outqueue); 1135 local_cork = 0; 1136 } 1137 asoc = cmd->obj.ptr; 1138 /* Register with the endpoint. */ 1139 sctp_endpoint_add_asoc(ep, asoc); 1140 sctp_hash_established(asoc); 1141 break; 1142 1143 case SCTP_CMD_UPDATE_ASSOC: 1144 sctp_assoc_update(asoc, cmd->obj.ptr); 1145 break; 1146 1147 case SCTP_CMD_PURGE_OUTQUEUE: 1148 sctp_outq_teardown(&asoc->outqueue); 1149 break; 1150 1151 case SCTP_CMD_DELETE_TCB: 1152 if (local_cork) { 1153 sctp_outq_uncork(&asoc->outqueue); 1154 local_cork = 0; 1155 } 1156 /* Delete the current association. */ 1157 sctp_cmd_delete_tcb(commands, asoc); 1158 asoc = NULL; 1159 break; 1160 1161 case SCTP_CMD_NEW_STATE: 1162 /* Enter a new state. */ 1163 sctp_cmd_new_state(commands, asoc, cmd->obj.state); 1164 break; 1165 1166 case SCTP_CMD_REPORT_TSN: 1167 /* Record the arrival of a TSN. */ 1168 error = sctp_tsnmap_mark(&asoc->peer.tsn_map, 1169 cmd->obj.u32); 1170 break; 1171 1172 case SCTP_CMD_REPORT_FWDTSN: 1173 /* Move the Cumulattive TSN Ack ahead. */ 1174 sctp_tsnmap_skip(&asoc->peer.tsn_map, cmd->obj.u32); 1175 1176 /* purge the fragmentation queue */ 1177 sctp_ulpq_reasm_flushtsn(&asoc->ulpq, cmd->obj.u32); 1178 1179 /* Abort any in progress partial delivery. */ 1180 sctp_ulpq_abort_pd(&asoc->ulpq, GFP_ATOMIC); 1181 break; 1182 1183 case SCTP_CMD_PROCESS_FWDTSN: 1184 sctp_cmd_process_fwdtsn(&asoc->ulpq, cmd->obj.ptr); 1185 break; 1186 1187 case SCTP_CMD_GEN_SACK: 1188 /* Generate a Selective ACK. 1189 * The argument tells us whether to just count 1190 * the packet and MAYBE generate a SACK, or 1191 * force a SACK out. 1192 */ 1193 force = cmd->obj.i32; 1194 error = sctp_gen_sack(asoc, force, commands); 1195 break; 1196 1197 case SCTP_CMD_PROCESS_SACK: 1198 /* Process an inbound SACK. */ 1199 error = sctp_cmd_process_sack(commands, asoc, 1200 cmd->obj.ptr); 1201 break; 1202 1203 case SCTP_CMD_GEN_INIT_ACK: 1204 /* Generate an INIT ACK chunk. */ 1205 new_obj = sctp_make_init_ack(asoc, chunk, GFP_ATOMIC, 1206 0); 1207 if (!new_obj) 1208 goto nomem; 1209 1210 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1211 SCTP_CHUNK(new_obj)); 1212 break; 1213 1214 case SCTP_CMD_PEER_INIT: 1215 /* Process a unified INIT from the peer. 1216 * Note: Only used during INIT-ACK processing. If 1217 * there is an error just return to the outter 1218 * layer which will bail. 1219 */ 1220 error = sctp_cmd_process_init(commands, asoc, chunk, 1221 cmd->obj.ptr, gfp); 1222 break; 1223 1224 case SCTP_CMD_GEN_COOKIE_ECHO: 1225 /* Generate a COOKIE ECHO chunk. */ 1226 new_obj = sctp_make_cookie_echo(asoc, chunk); 1227 if (!new_obj) { 1228 if (cmd->obj.ptr) 1229 sctp_chunk_free(cmd->obj.ptr); 1230 goto nomem; 1231 } 1232 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1233 SCTP_CHUNK(new_obj)); 1234 1235 /* If there is an ERROR chunk to be sent along with 1236 * the COOKIE_ECHO, send it, too. 1237 */ 1238 if (cmd->obj.ptr) 1239 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1240 SCTP_CHUNK(cmd->obj.ptr)); 1241 1242 if (new_obj->transport) { 1243 new_obj->transport->init_sent_count++; 1244 asoc->init_last_sent_to = new_obj->transport; 1245 } 1246 1247 /* FIXME - Eventually come up with a cleaner way to 1248 * enabling COOKIE-ECHO + DATA bundling during 1249 * multihoming stale cookie scenarios, the following 1250 * command plays with asoc->peer.retran_path to 1251 * avoid the problem of sending the COOKIE-ECHO and 1252 * DATA in different paths, which could result 1253 * in the association being ABORTed if the DATA chunk 1254 * is processed first by the server. Checking the 1255 * init error counter simply causes this command 1256 * to be executed only during failed attempts of 1257 * association establishment. 1258 */ 1259 if ((asoc->peer.retran_path != 1260 asoc->peer.primary_path) && 1261 (asoc->init_err_counter > 0)) { 1262 sctp_add_cmd_sf(commands, 1263 SCTP_CMD_FORCE_PRIM_RETRAN, 1264 SCTP_NULL()); 1265 } 1266 1267 break; 1268 1269 case SCTP_CMD_GEN_SHUTDOWN: 1270 /* Generate SHUTDOWN when in SHUTDOWN_SENT state. 1271 * Reset error counts. 1272 */ 1273 asoc->overall_error_count = 0; 1274 1275 /* Generate a SHUTDOWN chunk. */ 1276 new_obj = sctp_make_shutdown(asoc, chunk); 1277 if (!new_obj) 1278 goto nomem; 1279 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1280 SCTP_CHUNK(new_obj)); 1281 break; 1282 1283 case SCTP_CMD_CHUNK_ULP: 1284 /* Send a chunk to the sockets layer. */ 1285 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1286 "chunk_up:", cmd->obj.ptr, 1287 "ulpq:", &asoc->ulpq); 1288 sctp_ulpq_tail_data(&asoc->ulpq, cmd->obj.ptr, 1289 GFP_ATOMIC); 1290 break; 1291 1292 case SCTP_CMD_EVENT_ULP: 1293 /* Send a notification to the sockets layer. */ 1294 SCTP_DEBUG_PRINTK("sm_sideff: %s %p, %s %p.\n", 1295 "event_up:",cmd->obj.ptr, 1296 "ulpq:",&asoc->ulpq); 1297 sctp_ulpq_tail_event(&asoc->ulpq, cmd->obj.ptr); 1298 break; 1299 1300 case SCTP_CMD_REPLY: 1301 /* If an caller has not already corked, do cork. */ 1302 if (!asoc->outqueue.cork) { 1303 sctp_outq_cork(&asoc->outqueue); 1304 local_cork = 1; 1305 } 1306 /* Send a chunk to our peer. */ 1307 error = sctp_outq_tail(&asoc->outqueue, cmd->obj.ptr); 1308 break; 1309 1310 case SCTP_CMD_SEND_PKT: 1311 /* Send a full packet to our peer. */ 1312 packet = cmd->obj.ptr; 1313 sctp_packet_transmit(packet); 1314 sctp_ootb_pkt_free(packet); 1315 break; 1316 1317 case SCTP_CMD_T1_RETRAN: 1318 /* Mark a transport for retransmission. */ 1319 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1320 SCTP_RTXR_T1_RTX); 1321 break; 1322 1323 case SCTP_CMD_RETRAN: 1324 /* Mark a transport for retransmission. */ 1325 sctp_retransmit(&asoc->outqueue, cmd->obj.transport, 1326 SCTP_RTXR_T3_RTX); 1327 break; 1328 1329 case SCTP_CMD_TRANSMIT: 1330 /* Kick start transmission. */ 1331 error = sctp_outq_uncork(&asoc->outqueue); 1332 local_cork = 0; 1333 break; 1334 1335 case SCTP_CMD_ECN_CE: 1336 /* Do delayed CE processing. */ 1337 sctp_do_ecn_ce_work(asoc, cmd->obj.u32); 1338 break; 1339 1340 case SCTP_CMD_ECN_ECNE: 1341 /* Do delayed ECNE processing. */ 1342 new_obj = sctp_do_ecn_ecne_work(asoc, cmd->obj.u32, 1343 chunk); 1344 if (new_obj) 1345 sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, 1346 SCTP_CHUNK(new_obj)); 1347 break; 1348 1349 case SCTP_CMD_ECN_CWR: 1350 /* Do delayed CWR processing. */ 1351 sctp_do_ecn_cwr_work(asoc, cmd->obj.u32); 1352 break; 1353 1354 case SCTP_CMD_SETUP_T2: 1355 sctp_cmd_setup_t2(commands, asoc, cmd->obj.ptr); 1356 break; 1357 1358 case SCTP_CMD_TIMER_START: 1359 timer = &asoc->timers[cmd->obj.to]; 1360 timeout = asoc->timeouts[cmd->obj.to]; 1361 BUG_ON(!timeout); 1362 1363 timer->expires = jiffies + timeout; 1364 sctp_association_hold(asoc); 1365 add_timer(timer); 1366 break; 1367 1368 case SCTP_CMD_TIMER_RESTART: 1369 timer = &asoc->timers[cmd->obj.to]; 1370 timeout = asoc->timeouts[cmd->obj.to]; 1371 if (!mod_timer(timer, jiffies + timeout)) 1372 sctp_association_hold(asoc); 1373 break; 1374 1375 case SCTP_CMD_TIMER_STOP: 1376 timer = &asoc->timers[cmd->obj.to]; 1377 if (timer_pending(timer) && del_timer(timer)) 1378 sctp_association_put(asoc); 1379 break; 1380 1381 case SCTP_CMD_INIT_CHOOSE_TRANSPORT: 1382 chunk = cmd->obj.ptr; 1383 t = sctp_assoc_choose_alter_transport(asoc, 1384 asoc->init_last_sent_to); 1385 asoc->init_last_sent_to = t; 1386 chunk->transport = t; 1387 t->init_sent_count++; 1388 break; 1389 1390 case SCTP_CMD_INIT_RESTART: 1391 /* Do the needed accounting and updates 1392 * associated with restarting an initialization 1393 * timer. Only multiply the timeout by two if 1394 * all transports have been tried at the current 1395 * timeout. 1396 */ 1397 sctp_cmd_t1_timer_update(asoc, 1398 SCTP_EVENT_TIMEOUT_T1_INIT, 1399 "INIT"); 1400 1401 sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_RESTART, 1402 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); 1403 break; 1404 1405 case SCTP_CMD_COOKIEECHO_RESTART: 1406 /* Do the needed accounting and updates 1407 * associated with restarting an initialization 1408 * timer. Only multiply the timeout by two if 1409 * all transports have been tried at the current 1410 * timeout. 1411 */ 1412 sctp_cmd_t1_timer_update(asoc, 1413 SCTP_EVENT_TIMEOUT_T1_COOKIE, 1414 "COOKIE"); 1415 1416 /* If we've sent any data bundled with 1417 * COOKIE-ECHO we need to resend. 1418 */ 1419 list_for_each_entry(t, &asoc->peer.transport_addr_list, 1420 transports) { 1421 sctp_retransmit_mark(&asoc->outqueue, t, 1422 SCTP_RTXR_T1_RTX); 1423 } 1424 1425 sctp_add_cmd_sf(commands, 1426 SCTP_CMD_TIMER_RESTART, 1427 SCTP_TO(SCTP_EVENT_TIMEOUT_T1_COOKIE)); 1428 break; 1429 1430 case SCTP_CMD_INIT_FAILED: 1431 sctp_cmd_init_failed(commands, asoc, cmd->obj.err); 1432 break; 1433 1434 case SCTP_CMD_ASSOC_FAILED: 1435 sctp_cmd_assoc_failed(commands, asoc, event_type, 1436 subtype, chunk, cmd->obj.err); 1437 break; 1438 1439 case SCTP_CMD_INIT_COUNTER_INC: 1440 asoc->init_err_counter++; 1441 break; 1442 1443 case SCTP_CMD_INIT_COUNTER_RESET: 1444 asoc->init_err_counter = 0; 1445 asoc->init_cycle = 0; 1446 list_for_each_entry(t, &asoc->peer.transport_addr_list, 1447 transports) { 1448 t->init_sent_count = 0; 1449 } 1450 break; 1451 1452 case SCTP_CMD_REPORT_DUP: 1453 sctp_tsnmap_mark_dup(&asoc->peer.tsn_map, 1454 cmd->obj.u32); 1455 break; 1456 1457 case SCTP_CMD_REPORT_BAD_TAG: 1458 SCTP_DEBUG_PRINTK("vtag mismatch!\n"); 1459 break; 1460 1461 case SCTP_CMD_STRIKE: 1462 /* Mark one strike against a transport. */ 1463 sctp_do_8_2_transport_strike(asoc, cmd->obj.transport, 1464 0); 1465 break; 1466 1467 case SCTP_CMD_TRANSPORT_IDLE: 1468 t = cmd->obj.transport; 1469 sctp_transport_lower_cwnd(t, SCTP_LOWER_CWND_INACTIVE); 1470 break; 1471 1472 case SCTP_CMD_TRANSPORT_HB_SENT: 1473 t = cmd->obj.transport; 1474 sctp_do_8_2_transport_strike(asoc, t, 1); 1475 t->hb_sent = 1; 1476 break; 1477 1478 case SCTP_CMD_TRANSPORT_ON: 1479 t = cmd->obj.transport; 1480 sctp_cmd_transport_on(commands, asoc, t, chunk); 1481 break; 1482 1483 case SCTP_CMD_HB_TIMERS_START: 1484 sctp_cmd_hb_timers_start(commands, asoc); 1485 break; 1486 1487 case SCTP_CMD_HB_TIMER_UPDATE: 1488 t = cmd->obj.transport; 1489 sctp_cmd_hb_timer_update(commands, t); 1490 break; 1491 1492 case SCTP_CMD_HB_TIMERS_STOP: 1493 sctp_cmd_hb_timers_stop(commands, asoc); 1494 break; 1495 1496 case SCTP_CMD_REPORT_ERROR: 1497 error = cmd->obj.error; 1498 break; 1499 1500 case SCTP_CMD_PROCESS_CTSN: 1501 /* Dummy up a SACK for processing. */ 1502 sackh.cum_tsn_ack = cmd->obj.be32; 1503 sackh.a_rwnd = 0; 1504 sackh.num_gap_ack_blocks = 0; 1505 sackh.num_dup_tsns = 0; 1506 sctp_add_cmd_sf(commands, SCTP_CMD_PROCESS_SACK, 1507 SCTP_SACKH(&sackh)); 1508 break; 1509 1510 case SCTP_CMD_DISCARD_PACKET: 1511 /* We need to discard the whole packet. 1512 * Uncork the queue since there might be 1513 * responses pending 1514 */ 1515 chunk->pdiscard = 1; 1516 if (asoc) { 1517 sctp_outq_uncork(&asoc->outqueue); 1518 local_cork = 0; 1519 } 1520 break; 1521 1522 case SCTP_CMD_RTO_PENDING: 1523 t = cmd->obj.transport; 1524 t->rto_pending = 1; 1525 break; 1526 1527 case SCTP_CMD_PART_DELIVER: 1528 sctp_ulpq_partial_delivery(&asoc->ulpq, cmd->obj.ptr, 1529 GFP_ATOMIC); 1530 break; 1531 1532 case SCTP_CMD_RENEGE: 1533 sctp_ulpq_renege(&asoc->ulpq, cmd->obj.ptr, 1534 GFP_ATOMIC); 1535 break; 1536 1537 case SCTP_CMD_SETUP_T4: 1538 sctp_cmd_setup_t4(commands, asoc, cmd->obj.ptr); 1539 break; 1540 1541 case SCTP_CMD_PROCESS_OPERR: 1542 sctp_cmd_process_operr(commands, asoc, chunk); 1543 break; 1544 case SCTP_CMD_CLEAR_INIT_TAG: 1545 asoc->peer.i.init_tag = 0; 1546 break; 1547 case SCTP_CMD_DEL_NON_PRIMARY: 1548 sctp_cmd_del_non_primary(asoc); 1549 break; 1550 case SCTP_CMD_T3_RTX_TIMERS_STOP: 1551 sctp_cmd_t3_rtx_timers_stop(commands, asoc); 1552 break; 1553 case SCTP_CMD_FORCE_PRIM_RETRAN: 1554 t = asoc->peer.retran_path; 1555 asoc->peer.retran_path = asoc->peer.primary_path; 1556 error = sctp_outq_uncork(&asoc->outqueue); 1557 local_cork = 0; 1558 asoc->peer.retran_path = t; 1559 break; 1560 case SCTP_CMD_SET_SK_ERR: 1561 sctp_cmd_set_sk_err(asoc, cmd->obj.error); 1562 break; 1563 case SCTP_CMD_ASSOC_CHANGE: 1564 sctp_cmd_assoc_change(commands, asoc, 1565 cmd->obj.u8); 1566 break; 1567 case SCTP_CMD_ADAPTATION_IND: 1568 sctp_cmd_adaptation_ind(commands, asoc); 1569 break; 1570 1571 case SCTP_CMD_ASSOC_SHKEY: 1572 error = sctp_auth_asoc_init_active_key(asoc, 1573 GFP_ATOMIC); 1574 break; 1575 case SCTP_CMD_UPDATE_INITTAG: 1576 asoc->peer.i.init_tag = cmd->obj.u32; 1577 break; 1578 1579 default: 1580 printk(KERN_WARNING "Impossible command: %u, %p\n", 1581 cmd->verb, cmd->obj.ptr); 1582 break; 1583 } 1584 1585 if (error) 1586 break; 1587 } 1588 1589 out: 1590 /* If this is in response to a received chunk, wait until 1591 * we are done with the packet to open the queue so that we don't 1592 * send multiple packets in response to a single request. 1593 */ 1594 if (asoc && SCTP_EVENT_T_CHUNK == event_type && chunk) { 1595 if (chunk->end_of_packet || chunk->singleton) 1596 sctp_outq_uncork(&asoc->outqueue); 1597 } else if (local_cork) 1598 sctp_outq_uncork(&asoc->outqueue); 1599 return error; 1600 nomem: 1601 error = -ENOMEM; 1602 goto out; 1603 } 1604 1605