1 /* 2 * Connection tracking protocol helper module for SCTP. 3 * 4 * Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com> 5 * Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net> 6 * 7 * SCTP is defined in RFC 2960. References to various sections in this code 8 * are to this RFC. 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License version 2 as 12 * published by the Free Software Foundation. 13 */ 14 15 #include <linux/types.h> 16 #include <linux/timer.h> 17 #include <linux/netfilter.h> 18 #include <linux/module.h> 19 #include <linux/in.h> 20 #include <linux/ip.h> 21 #include <linux/sctp.h> 22 #include <linux/string.h> 23 #include <linux/seq_file.h> 24 #include <linux/spinlock.h> 25 #include <linux/interrupt.h> 26 27 #include <net/netfilter/nf_conntrack.h> 28 #include <net/netfilter/nf_conntrack_l4proto.h> 29 #include <net/netfilter/nf_conntrack_ecache.h> 30 31 /* FIXME: Examine ipfilter's timeouts and conntrack transitions more 32 closely. They're more complex. --RR 33 34 And so for me for SCTP :D -Kiran */ 35 36 static const char *const sctp_conntrack_names[] = { 37 "NONE", 38 "CLOSED", 39 "COOKIE_WAIT", 40 "COOKIE_ECHOED", 41 "ESTABLISHED", 42 "SHUTDOWN_SENT", 43 "SHUTDOWN_RECD", 44 "SHUTDOWN_ACK_SENT", 45 "HEARTBEAT_SENT", 46 "HEARTBEAT_ACKED", 47 }; 48 49 #define SECS * HZ 50 #define MINS * 60 SECS 51 #define HOURS * 60 MINS 52 #define DAYS * 24 HOURS 53 54 static unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] __read_mostly = { 55 [SCTP_CONNTRACK_CLOSED] = 10 SECS, 56 [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS, 57 [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS, 58 [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS, 59 [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000, 60 [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000, 61 [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS, 62 [SCTP_CONNTRACK_HEARTBEAT_SENT] = 30 SECS, 63 [SCTP_CONNTRACK_HEARTBEAT_ACKED] = 210 SECS, 64 }; 65 66 #define sNO SCTP_CONNTRACK_NONE 67 #define sCL SCTP_CONNTRACK_CLOSED 68 #define sCW SCTP_CONNTRACK_COOKIE_WAIT 69 #define sCE SCTP_CONNTRACK_COOKIE_ECHOED 70 #define sES SCTP_CONNTRACK_ESTABLISHED 71 #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT 72 #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD 73 #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT 74 #define sHS SCTP_CONNTRACK_HEARTBEAT_SENT 75 #define sHA SCTP_CONNTRACK_HEARTBEAT_ACKED 76 #define sIV SCTP_CONNTRACK_MAX 77 78 /* 79 These are the descriptions of the states: 80 81 NOTE: These state names are tantalizingly similar to the states of an 82 SCTP endpoint. But the interpretation of the states is a little different, 83 considering that these are the states of the connection and not of an end 84 point. Please note the subtleties. -Kiran 85 86 NONE - Nothing so far. 87 COOKIE WAIT - We have seen an INIT chunk in the original direction, or also 88 an INIT_ACK chunk in the reply direction. 89 COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction. 90 ESTABLISHED - We have seen a COOKIE_ACK in the reply direction. 91 SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction. 92 SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin. 93 SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite 94 to that of the SHUTDOWN chunk. 95 CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of 96 the SHUTDOWN chunk. Connection is closed. 97 HEARTBEAT_SENT - We have seen a HEARTBEAT in a new flow. 98 HEARTBEAT_ACKED - We have seen a HEARTBEAT-ACK in the direction opposite to 99 that of the HEARTBEAT chunk. Secondary connection is 100 established. 101 */ 102 103 /* TODO 104 - I have assumed that the first INIT is in the original direction. 105 This messes things when an INIT comes in the reply direction in CLOSED 106 state. 107 - Check the error type in the reply dir before transitioning from 108 cookie echoed to closed. 109 - Sec 5.2.4 of RFC 2960 110 - Full Multi Homing support. 111 */ 112 113 /* SCTP conntrack state transitions */ 114 static const u8 sctp_conntracks[2][11][SCTP_CONNTRACK_MAX] = { 115 { 116 /* ORIGINAL */ 117 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */ 118 /* init */ {sCW, sCW, sCW, sCE, sES, sSS, sSR, sSA, sCW, sHA}, 119 /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA}, 120 /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL}, 121 /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA, sCL, sSS}, 122 /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA, sHA}, 123 /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't have Stale cookie*/ 124 /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* 5.2.4 - Big TODO */ 125 /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't come in orig dir */ 126 /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL, sCL, sHA}, 127 /* heartbeat */ {sHS, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}, 128 /* heartbeat_ack*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA} 129 }, 130 { 131 /* REPLY */ 132 /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */ 133 /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* INIT in sCL Big TODO */ 134 /* init_ack */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA}, 135 /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sIV, sCL}, 136 /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA, sIV, sSR}, 137 /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA, sIV, sHA}, 138 /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA, sIV, sHA}, 139 /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* Can't come in reply dir */ 140 /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA, sIV, sHA}, 141 /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL, sIV, sHA}, 142 /* heartbeat */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}, 143 /* heartbeat_ack*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHA, sHA} 144 } 145 }; 146 147 static int sctp_net_id __read_mostly; 148 struct sctp_net { 149 struct nf_proto_net pn; 150 unsigned int timeouts[SCTP_CONNTRACK_MAX]; 151 }; 152 153 static inline struct sctp_net *sctp_pernet(struct net *net) 154 { 155 return net_generic(net, sctp_net_id); 156 } 157 158 static bool sctp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff, 159 struct net *net, struct nf_conntrack_tuple *tuple) 160 { 161 const struct sctphdr *hp; 162 struct sctphdr _hdr; 163 164 /* Actually only need first 8 bytes. */ 165 hp = skb_header_pointer(skb, dataoff, 8, &_hdr); 166 if (hp == NULL) 167 return false; 168 169 tuple->src.u.sctp.port = hp->source; 170 tuple->dst.u.sctp.port = hp->dest; 171 return true; 172 } 173 174 static bool sctp_invert_tuple(struct nf_conntrack_tuple *tuple, 175 const struct nf_conntrack_tuple *orig) 176 { 177 tuple->src.u.sctp.port = orig->dst.u.sctp.port; 178 tuple->dst.u.sctp.port = orig->src.u.sctp.port; 179 return true; 180 } 181 182 /* Print out the per-protocol part of the tuple. */ 183 static void sctp_print_tuple(struct seq_file *s, 184 const struct nf_conntrack_tuple *tuple) 185 { 186 seq_printf(s, "sport=%hu dport=%hu ", 187 ntohs(tuple->src.u.sctp.port), 188 ntohs(tuple->dst.u.sctp.port)); 189 } 190 191 /* Print out the private part of the conntrack. */ 192 static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct) 193 { 194 enum sctp_conntrack state; 195 196 spin_lock_bh(&ct->lock); 197 state = ct->proto.sctp.state; 198 spin_unlock_bh(&ct->lock); 199 200 seq_printf(s, "%s ", sctp_conntrack_names[state]); 201 } 202 203 #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \ 204 for ((offset) = (dataoff) + sizeof(sctp_sctphdr_t), (count) = 0; \ 205 (offset) < (skb)->len && \ 206 ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \ 207 (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++) 208 209 /* Some validity checks to make sure the chunks are fine */ 210 static int do_basic_checks(struct nf_conn *ct, 211 const struct sk_buff *skb, 212 unsigned int dataoff, 213 unsigned long *map) 214 { 215 u_int32_t offset, count; 216 sctp_chunkhdr_t _sch, *sch; 217 int flag; 218 219 flag = 0; 220 221 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 222 pr_debug("Chunk Num: %d Type: %d\n", count, sch->type); 223 224 if (sch->type == SCTP_CID_INIT || 225 sch->type == SCTP_CID_INIT_ACK || 226 sch->type == SCTP_CID_SHUTDOWN_COMPLETE) 227 flag = 1; 228 229 /* 230 * Cookie Ack/Echo chunks not the first OR 231 * Init / Init Ack / Shutdown compl chunks not the only chunks 232 * OR zero-length. 233 */ 234 if (((sch->type == SCTP_CID_COOKIE_ACK || 235 sch->type == SCTP_CID_COOKIE_ECHO || 236 flag) && 237 count != 0) || !sch->length) { 238 pr_debug("Basic checks failed\n"); 239 return 1; 240 } 241 242 if (map) 243 set_bit(sch->type, map); 244 } 245 246 pr_debug("Basic checks passed\n"); 247 return count == 0; 248 } 249 250 static int sctp_new_state(enum ip_conntrack_dir dir, 251 enum sctp_conntrack cur_state, 252 int chunk_type) 253 { 254 int i; 255 256 pr_debug("Chunk type: %d\n", chunk_type); 257 258 switch (chunk_type) { 259 case SCTP_CID_INIT: 260 pr_debug("SCTP_CID_INIT\n"); 261 i = 0; 262 break; 263 case SCTP_CID_INIT_ACK: 264 pr_debug("SCTP_CID_INIT_ACK\n"); 265 i = 1; 266 break; 267 case SCTP_CID_ABORT: 268 pr_debug("SCTP_CID_ABORT\n"); 269 i = 2; 270 break; 271 case SCTP_CID_SHUTDOWN: 272 pr_debug("SCTP_CID_SHUTDOWN\n"); 273 i = 3; 274 break; 275 case SCTP_CID_SHUTDOWN_ACK: 276 pr_debug("SCTP_CID_SHUTDOWN_ACK\n"); 277 i = 4; 278 break; 279 case SCTP_CID_ERROR: 280 pr_debug("SCTP_CID_ERROR\n"); 281 i = 5; 282 break; 283 case SCTP_CID_COOKIE_ECHO: 284 pr_debug("SCTP_CID_COOKIE_ECHO\n"); 285 i = 6; 286 break; 287 case SCTP_CID_COOKIE_ACK: 288 pr_debug("SCTP_CID_COOKIE_ACK\n"); 289 i = 7; 290 break; 291 case SCTP_CID_SHUTDOWN_COMPLETE: 292 pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n"); 293 i = 8; 294 break; 295 case SCTP_CID_HEARTBEAT: 296 pr_debug("SCTP_CID_HEARTBEAT"); 297 i = 9; 298 break; 299 case SCTP_CID_HEARTBEAT_ACK: 300 pr_debug("SCTP_CID_HEARTBEAT_ACK"); 301 i = 10; 302 break; 303 default: 304 /* Other chunks like DATA or SACK do not change the state */ 305 pr_debug("Unknown chunk type, Will stay in %s\n", 306 sctp_conntrack_names[cur_state]); 307 return cur_state; 308 } 309 310 pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n", 311 dir, sctp_conntrack_names[cur_state], chunk_type, 312 sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]); 313 314 return sctp_conntracks[dir][i][cur_state]; 315 } 316 317 static unsigned int *sctp_get_timeouts(struct net *net) 318 { 319 return sctp_pernet(net)->timeouts; 320 } 321 322 /* Returns verdict for packet, or -NF_ACCEPT for invalid. */ 323 static int sctp_packet(struct nf_conn *ct, 324 const struct sk_buff *skb, 325 unsigned int dataoff, 326 enum ip_conntrack_info ctinfo, 327 u_int8_t pf, 328 unsigned int hooknum, 329 unsigned int *timeouts) 330 { 331 enum sctp_conntrack new_state, old_state; 332 enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo); 333 const struct sctphdr *sh; 334 struct sctphdr _sctph; 335 const struct sctp_chunkhdr *sch; 336 struct sctp_chunkhdr _sch; 337 u_int32_t offset, count; 338 unsigned long map[256 / sizeof(unsigned long)] = { 0 }; 339 340 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); 341 if (sh == NULL) 342 goto out; 343 344 if (do_basic_checks(ct, skb, dataoff, map) != 0) 345 goto out; 346 347 /* Check the verification tag (Sec 8.5) */ 348 if (!test_bit(SCTP_CID_INIT, map) && 349 !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) && 350 !test_bit(SCTP_CID_COOKIE_ECHO, map) && 351 !test_bit(SCTP_CID_ABORT, map) && 352 !test_bit(SCTP_CID_SHUTDOWN_ACK, map) && 353 !test_bit(SCTP_CID_HEARTBEAT, map) && 354 !test_bit(SCTP_CID_HEARTBEAT_ACK, map) && 355 sh->vtag != ct->proto.sctp.vtag[dir]) { 356 pr_debug("Verification tag check failed\n"); 357 goto out; 358 } 359 360 old_state = new_state = SCTP_CONNTRACK_NONE; 361 spin_lock_bh(&ct->lock); 362 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 363 /* Special cases of Verification tag check (Sec 8.5.1) */ 364 if (sch->type == SCTP_CID_INIT) { 365 /* Sec 8.5.1 (A) */ 366 if (sh->vtag != 0) 367 goto out_unlock; 368 } else if (sch->type == SCTP_CID_ABORT) { 369 /* Sec 8.5.1 (B) */ 370 if (sh->vtag != ct->proto.sctp.vtag[dir] && 371 sh->vtag != ct->proto.sctp.vtag[!dir]) 372 goto out_unlock; 373 } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) { 374 /* Sec 8.5.1 (C) */ 375 if (sh->vtag != ct->proto.sctp.vtag[dir] && 376 sh->vtag != ct->proto.sctp.vtag[!dir] && 377 sch->flags & SCTP_CHUNK_FLAG_T) 378 goto out_unlock; 379 } else if (sch->type == SCTP_CID_COOKIE_ECHO) { 380 /* Sec 8.5.1 (D) */ 381 if (sh->vtag != ct->proto.sctp.vtag[dir]) 382 goto out_unlock; 383 } else if (sch->type == SCTP_CID_HEARTBEAT || 384 sch->type == SCTP_CID_HEARTBEAT_ACK) { 385 if (ct->proto.sctp.vtag[dir] == 0) { 386 pr_debug("Setting vtag %x for dir %d\n", 387 sh->vtag, dir); 388 ct->proto.sctp.vtag[dir] = sh->vtag; 389 } else if (sh->vtag != ct->proto.sctp.vtag[dir]) { 390 pr_debug("Verification tag check failed\n"); 391 goto out_unlock; 392 } 393 } 394 395 old_state = ct->proto.sctp.state; 396 new_state = sctp_new_state(dir, old_state, sch->type); 397 398 /* Invalid */ 399 if (new_state == SCTP_CONNTRACK_MAX) { 400 pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u " 401 "conntrack=%u\n", 402 dir, sch->type, old_state); 403 goto out_unlock; 404 } 405 406 /* If it is an INIT or an INIT ACK note down the vtag */ 407 if (sch->type == SCTP_CID_INIT || 408 sch->type == SCTP_CID_INIT_ACK) { 409 sctp_inithdr_t _inithdr, *ih; 410 411 ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t), 412 sizeof(_inithdr), &_inithdr); 413 if (ih == NULL) 414 goto out_unlock; 415 pr_debug("Setting vtag %x for dir %d\n", 416 ih->init_tag, !dir); 417 ct->proto.sctp.vtag[!dir] = ih->init_tag; 418 } 419 420 ct->proto.sctp.state = new_state; 421 if (old_state != new_state) 422 nf_conntrack_event_cache(IPCT_PROTOINFO, ct); 423 } 424 spin_unlock_bh(&ct->lock); 425 426 nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]); 427 428 if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED && 429 dir == IP_CT_DIR_REPLY && 430 new_state == SCTP_CONNTRACK_ESTABLISHED) { 431 pr_debug("Setting assured bit\n"); 432 set_bit(IPS_ASSURED_BIT, &ct->status); 433 nf_conntrack_event_cache(IPCT_ASSURED, ct); 434 } 435 436 return NF_ACCEPT; 437 438 out_unlock: 439 spin_unlock_bh(&ct->lock); 440 out: 441 return -NF_ACCEPT; 442 } 443 444 /* Called when a new connection for this protocol found. */ 445 static bool sctp_new(struct nf_conn *ct, const struct sk_buff *skb, 446 unsigned int dataoff, unsigned int *timeouts) 447 { 448 enum sctp_conntrack new_state; 449 const struct sctphdr *sh; 450 struct sctphdr _sctph; 451 const struct sctp_chunkhdr *sch; 452 struct sctp_chunkhdr _sch; 453 u_int32_t offset, count; 454 unsigned long map[256 / sizeof(unsigned long)] = { 0 }; 455 456 sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph); 457 if (sh == NULL) 458 return false; 459 460 if (do_basic_checks(ct, skb, dataoff, map) != 0) 461 return false; 462 463 /* If an OOTB packet has any of these chunks discard (Sec 8.4) */ 464 if (test_bit(SCTP_CID_ABORT, map) || 465 test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) || 466 test_bit(SCTP_CID_COOKIE_ACK, map)) 467 return false; 468 469 memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp)); 470 new_state = SCTP_CONNTRACK_MAX; 471 for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) { 472 /* Don't need lock here: this conntrack not in circulation yet */ 473 new_state = sctp_new_state(IP_CT_DIR_ORIGINAL, 474 SCTP_CONNTRACK_NONE, sch->type); 475 476 /* Invalid: delete conntrack */ 477 if (new_state == SCTP_CONNTRACK_NONE || 478 new_state == SCTP_CONNTRACK_MAX) { 479 pr_debug("nf_conntrack_sctp: invalid new deleting.\n"); 480 return false; 481 } 482 483 /* Copy the vtag into the state info */ 484 if (sch->type == SCTP_CID_INIT) { 485 if (sh->vtag == 0) { 486 sctp_inithdr_t _inithdr, *ih; 487 488 ih = skb_header_pointer(skb, offset + sizeof(sctp_chunkhdr_t), 489 sizeof(_inithdr), &_inithdr); 490 if (ih == NULL) 491 return false; 492 493 pr_debug("Setting vtag %x for new conn\n", 494 ih->init_tag); 495 496 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = 497 ih->init_tag; 498 } else { 499 /* Sec 8.5.1 (A) */ 500 return false; 501 } 502 } else if (sch->type == SCTP_CID_HEARTBEAT) { 503 pr_debug("Setting vtag %x for secondary conntrack\n", 504 sh->vtag); 505 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag; 506 } 507 /* If it is a shutdown ack OOTB packet, we expect a return 508 shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */ 509 else { 510 pr_debug("Setting vtag %x for new conn OOTB\n", 511 sh->vtag); 512 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag; 513 } 514 515 ct->proto.sctp.state = new_state; 516 } 517 518 return true; 519 } 520 521 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 522 523 #include <linux/netfilter/nfnetlink.h> 524 #include <linux/netfilter/nfnetlink_conntrack.h> 525 526 static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla, 527 struct nf_conn *ct) 528 { 529 struct nlattr *nest_parms; 530 531 spin_lock_bh(&ct->lock); 532 nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP | NLA_F_NESTED); 533 if (!nest_parms) 534 goto nla_put_failure; 535 536 if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state) || 537 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL, 538 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) || 539 nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY, 540 ct->proto.sctp.vtag[IP_CT_DIR_REPLY])) 541 goto nla_put_failure; 542 543 spin_unlock_bh(&ct->lock); 544 545 nla_nest_end(skb, nest_parms); 546 547 return 0; 548 549 nla_put_failure: 550 spin_unlock_bh(&ct->lock); 551 return -1; 552 } 553 554 static const struct nla_policy sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = { 555 [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 }, 556 [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 }, 557 [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 }, 558 }; 559 560 static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct) 561 { 562 struct nlattr *attr = cda[CTA_PROTOINFO_SCTP]; 563 struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1]; 564 int err; 565 566 /* updates may not contain the internal protocol info, skip parsing */ 567 if (!attr) 568 return 0; 569 570 err = nla_parse_nested(tb, 571 CTA_PROTOINFO_SCTP_MAX, 572 attr, 573 sctp_nla_policy); 574 if (err < 0) 575 return err; 576 577 if (!tb[CTA_PROTOINFO_SCTP_STATE] || 578 !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] || 579 !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]) 580 return -EINVAL; 581 582 spin_lock_bh(&ct->lock); 583 ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]); 584 ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = 585 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]); 586 ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = 587 nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]); 588 spin_unlock_bh(&ct->lock); 589 590 return 0; 591 } 592 593 static int sctp_nlattr_size(void) 594 { 595 return nla_total_size(0) /* CTA_PROTOINFO_SCTP */ 596 + nla_policy_len(sctp_nla_policy, CTA_PROTOINFO_SCTP_MAX + 1); 597 } 598 #endif 599 600 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 601 602 #include <linux/netfilter/nfnetlink.h> 603 #include <linux/netfilter/nfnetlink_cttimeout.h> 604 605 static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[], 606 struct net *net, void *data) 607 { 608 unsigned int *timeouts = data; 609 struct sctp_net *sn = sctp_pernet(net); 610 int i; 611 612 /* set default SCTP timeouts. */ 613 for (i=0; i<SCTP_CONNTRACK_MAX; i++) 614 timeouts[i] = sn->timeouts[i]; 615 616 /* there's a 1:1 mapping between attributes and protocol states. */ 617 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 618 if (tb[i]) { 619 timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ; 620 } 621 } 622 return 0; 623 } 624 625 static int 626 sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data) 627 { 628 const unsigned int *timeouts = data; 629 int i; 630 631 for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) { 632 if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ))) 633 goto nla_put_failure; 634 } 635 return 0; 636 637 nla_put_failure: 638 return -ENOSPC; 639 } 640 641 static const struct nla_policy 642 sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = { 643 [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 }, 644 [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 }, 645 [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 }, 646 [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 }, 647 [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 }, 648 [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 }, 649 [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 }, 650 [CTA_TIMEOUT_SCTP_HEARTBEAT_SENT] = { .type = NLA_U32 }, 651 [CTA_TIMEOUT_SCTP_HEARTBEAT_ACKED] = { .type = NLA_U32 }, 652 }; 653 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ 654 655 656 #ifdef CONFIG_SYSCTL 657 static struct ctl_table sctp_sysctl_table[] = { 658 { 659 .procname = "nf_conntrack_sctp_timeout_closed", 660 .maxlen = sizeof(unsigned int), 661 .mode = 0644, 662 .proc_handler = proc_dointvec_jiffies, 663 }, 664 { 665 .procname = "nf_conntrack_sctp_timeout_cookie_wait", 666 .maxlen = sizeof(unsigned int), 667 .mode = 0644, 668 .proc_handler = proc_dointvec_jiffies, 669 }, 670 { 671 .procname = "nf_conntrack_sctp_timeout_cookie_echoed", 672 .maxlen = sizeof(unsigned int), 673 .mode = 0644, 674 .proc_handler = proc_dointvec_jiffies, 675 }, 676 { 677 .procname = "nf_conntrack_sctp_timeout_established", 678 .maxlen = sizeof(unsigned int), 679 .mode = 0644, 680 .proc_handler = proc_dointvec_jiffies, 681 }, 682 { 683 .procname = "nf_conntrack_sctp_timeout_shutdown_sent", 684 .maxlen = sizeof(unsigned int), 685 .mode = 0644, 686 .proc_handler = proc_dointvec_jiffies, 687 }, 688 { 689 .procname = "nf_conntrack_sctp_timeout_shutdown_recd", 690 .maxlen = sizeof(unsigned int), 691 .mode = 0644, 692 .proc_handler = proc_dointvec_jiffies, 693 }, 694 { 695 .procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent", 696 .maxlen = sizeof(unsigned int), 697 .mode = 0644, 698 .proc_handler = proc_dointvec_jiffies, 699 }, 700 { 701 .procname = "nf_conntrack_sctp_timeout_heartbeat_sent", 702 .maxlen = sizeof(unsigned int), 703 .mode = 0644, 704 .proc_handler = proc_dointvec_jiffies, 705 }, 706 { 707 .procname = "nf_conntrack_sctp_timeout_heartbeat_acked", 708 .maxlen = sizeof(unsigned int), 709 .mode = 0644, 710 .proc_handler = proc_dointvec_jiffies, 711 }, 712 { } 713 }; 714 715 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT 716 static struct ctl_table sctp_compat_sysctl_table[] = { 717 { 718 .procname = "ip_conntrack_sctp_timeout_closed", 719 .maxlen = sizeof(unsigned int), 720 .mode = 0644, 721 .proc_handler = proc_dointvec_jiffies, 722 }, 723 { 724 .procname = "ip_conntrack_sctp_timeout_cookie_wait", 725 .maxlen = sizeof(unsigned int), 726 .mode = 0644, 727 .proc_handler = proc_dointvec_jiffies, 728 }, 729 { 730 .procname = "ip_conntrack_sctp_timeout_cookie_echoed", 731 .maxlen = sizeof(unsigned int), 732 .mode = 0644, 733 .proc_handler = proc_dointvec_jiffies, 734 }, 735 { 736 .procname = "ip_conntrack_sctp_timeout_established", 737 .maxlen = sizeof(unsigned int), 738 .mode = 0644, 739 .proc_handler = proc_dointvec_jiffies, 740 }, 741 { 742 .procname = "ip_conntrack_sctp_timeout_shutdown_sent", 743 .maxlen = sizeof(unsigned int), 744 .mode = 0644, 745 .proc_handler = proc_dointvec_jiffies, 746 }, 747 { 748 .procname = "ip_conntrack_sctp_timeout_shutdown_recd", 749 .maxlen = sizeof(unsigned int), 750 .mode = 0644, 751 .proc_handler = proc_dointvec_jiffies, 752 }, 753 { 754 .procname = "ip_conntrack_sctp_timeout_shutdown_ack_sent", 755 .maxlen = sizeof(unsigned int), 756 .mode = 0644, 757 .proc_handler = proc_dointvec_jiffies, 758 }, 759 { } 760 }; 761 #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */ 762 #endif 763 764 static int sctp_kmemdup_sysctl_table(struct nf_proto_net *pn, 765 struct sctp_net *sn) 766 { 767 #ifdef CONFIG_SYSCTL 768 if (pn->ctl_table) 769 return 0; 770 771 pn->ctl_table = kmemdup(sctp_sysctl_table, 772 sizeof(sctp_sysctl_table), 773 GFP_KERNEL); 774 if (!pn->ctl_table) 775 return -ENOMEM; 776 777 pn->ctl_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED]; 778 pn->ctl_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT]; 779 pn->ctl_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED]; 780 pn->ctl_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED]; 781 pn->ctl_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT]; 782 pn->ctl_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD]; 783 pn->ctl_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT]; 784 pn->ctl_table[7].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_SENT]; 785 pn->ctl_table[8].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_ACKED]; 786 #endif 787 return 0; 788 } 789 790 static int sctp_kmemdup_compat_sysctl_table(struct nf_proto_net *pn, 791 struct sctp_net *sn) 792 { 793 #ifdef CONFIG_SYSCTL 794 #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT 795 pn->ctl_compat_table = kmemdup(sctp_compat_sysctl_table, 796 sizeof(sctp_compat_sysctl_table), 797 GFP_KERNEL); 798 if (!pn->ctl_compat_table) 799 return -ENOMEM; 800 801 pn->ctl_compat_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED]; 802 pn->ctl_compat_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT]; 803 pn->ctl_compat_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED]; 804 pn->ctl_compat_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED]; 805 pn->ctl_compat_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT]; 806 pn->ctl_compat_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD]; 807 pn->ctl_compat_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT]; 808 #endif 809 #endif 810 return 0; 811 } 812 813 static int sctp_init_net(struct net *net, u_int16_t proto) 814 { 815 int ret; 816 struct sctp_net *sn = sctp_pernet(net); 817 struct nf_proto_net *pn = &sn->pn; 818 819 if (!pn->users) { 820 int i; 821 822 for (i = 0; i < SCTP_CONNTRACK_MAX; i++) 823 sn->timeouts[i] = sctp_timeouts[i]; 824 } 825 826 if (proto == AF_INET) { 827 ret = sctp_kmemdup_compat_sysctl_table(pn, sn); 828 if (ret < 0) 829 return ret; 830 831 ret = sctp_kmemdup_sysctl_table(pn, sn); 832 if (ret < 0) 833 nf_ct_kfree_compat_sysctl_table(pn); 834 } else 835 ret = sctp_kmemdup_sysctl_table(pn, sn); 836 837 return ret; 838 } 839 840 static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = { 841 .l3proto = PF_INET, 842 .l4proto = IPPROTO_SCTP, 843 .name = "sctp", 844 .pkt_to_tuple = sctp_pkt_to_tuple, 845 .invert_tuple = sctp_invert_tuple, 846 .print_tuple = sctp_print_tuple, 847 .print_conntrack = sctp_print_conntrack, 848 .packet = sctp_packet, 849 .get_timeouts = sctp_get_timeouts, 850 .new = sctp_new, 851 .me = THIS_MODULE, 852 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 853 .to_nlattr = sctp_to_nlattr, 854 .nlattr_size = sctp_nlattr_size, 855 .from_nlattr = nlattr_to_sctp, 856 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 857 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 858 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 859 .nla_policy = nf_ct_port_nla_policy, 860 #endif 861 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 862 .ctnl_timeout = { 863 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 864 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 865 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 866 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 867 .nla_policy = sctp_timeout_nla_policy, 868 }, 869 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ 870 .net_id = &sctp_net_id, 871 .init_net = sctp_init_net, 872 }; 873 874 static struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = { 875 .l3proto = PF_INET6, 876 .l4proto = IPPROTO_SCTP, 877 .name = "sctp", 878 .pkt_to_tuple = sctp_pkt_to_tuple, 879 .invert_tuple = sctp_invert_tuple, 880 .print_tuple = sctp_print_tuple, 881 .print_conntrack = sctp_print_conntrack, 882 .packet = sctp_packet, 883 .get_timeouts = sctp_get_timeouts, 884 .new = sctp_new, 885 .me = THIS_MODULE, 886 #if IS_ENABLED(CONFIG_NF_CT_NETLINK) 887 .to_nlattr = sctp_to_nlattr, 888 .nlattr_size = sctp_nlattr_size, 889 .from_nlattr = nlattr_to_sctp, 890 .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr, 891 .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size, 892 .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple, 893 .nla_policy = nf_ct_port_nla_policy, 894 #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT) 895 .ctnl_timeout = { 896 .nlattr_to_obj = sctp_timeout_nlattr_to_obj, 897 .obj_to_nlattr = sctp_timeout_obj_to_nlattr, 898 .nlattr_max = CTA_TIMEOUT_SCTP_MAX, 899 .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX, 900 .nla_policy = sctp_timeout_nla_policy, 901 }, 902 #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ 903 #endif 904 .net_id = &sctp_net_id, 905 .init_net = sctp_init_net, 906 }; 907 908 static int sctp_net_init(struct net *net) 909 { 910 int ret = 0; 911 912 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_sctp4); 913 if (ret < 0) { 914 pr_err("nf_conntrack_sctp4: pernet registration failed.\n"); 915 goto out; 916 } 917 ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_sctp6); 918 if (ret < 0) { 919 pr_err("nf_conntrack_sctp6: pernet registration failed.\n"); 920 goto cleanup_sctp4; 921 } 922 return 0; 923 924 cleanup_sctp4: 925 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp4); 926 out: 927 return ret; 928 } 929 930 static void sctp_net_exit(struct net *net) 931 { 932 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp6); 933 nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_sctp4); 934 } 935 936 static struct pernet_operations sctp_net_ops = { 937 .init = sctp_net_init, 938 .exit = sctp_net_exit, 939 .id = &sctp_net_id, 940 .size = sizeof(struct sctp_net), 941 }; 942 943 static int __init nf_conntrack_proto_sctp_init(void) 944 { 945 int ret; 946 947 ret = register_pernet_subsys(&sctp_net_ops); 948 if (ret < 0) 949 goto out_pernet; 950 951 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_sctp4); 952 if (ret < 0) 953 goto out_sctp4; 954 955 ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_sctp6); 956 if (ret < 0) 957 goto out_sctp6; 958 959 return 0; 960 out_sctp6: 961 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp4); 962 out_sctp4: 963 unregister_pernet_subsys(&sctp_net_ops); 964 out_pernet: 965 return ret; 966 } 967 968 static void __exit nf_conntrack_proto_sctp_fini(void) 969 { 970 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp6); 971 nf_ct_l4proto_unregister(&nf_conntrack_l4proto_sctp4); 972 unregister_pernet_subsys(&sctp_net_ops); 973 } 974 975 module_init(nf_conntrack_proto_sctp_init); 976 module_exit(nf_conntrack_proto_sctp_fini); 977 978 MODULE_LICENSE("GPL"); 979 MODULE_AUTHOR("Kiran Kumar Immidi"); 980 MODULE_DESCRIPTION("Netfilter connection tracking protocol helper for SCTP"); 981 MODULE_ALIAS("ip_conntrack_proto_sctp"); 982