Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* SCTP kernel reference Implementation |
| 2 | * (C) Copyright IBM Corp. 2001, 2004 |
| 3 | * Copyright (c) 1999-2000 Cisco, Inc. |
| 4 | * Copyright (c) 1999-2001 Motorola, Inc. |
| 5 | * Copyright (c) 2001-2002 Intel Corp. |
| 6 | * |
| 7 | * This file is part of the SCTP kernel reference Implementation |
| 8 | * |
| 9 | * These functions work with the state functions in sctp_sm_statefuns.c |
| 10 | * to implement the state operations. These functions implement the |
| 11 | * steps which require modifying existing data structures. |
| 12 | * |
| 13 | * The SCTP reference implementation is free software; |
| 14 | * you can redistribute it and/or modify it under the terms of |
| 15 | * the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2, or (at your option) |
| 17 | * any later version. |
| 18 | * |
| 19 | * The SCTP reference implementation is distributed in the hope that it |
| 20 | * will be useful, but WITHOUT ANY WARRANTY; without even the implied |
| 21 | * ************************ |
| 22 | * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. |
| 23 | * See the GNU General Public License for more details. |
| 24 | * |
| 25 | * You should have received a copy of the GNU General Public License |
| 26 | * along with GNU CC; see the file COPYING. If not, write to |
| 27 | * the Free Software Foundation, 59 Temple Place - Suite 330, |
| 28 | * Boston, MA 02111-1307, USA. |
| 29 | * |
| 30 | * Please send any bug reports or fixes you make to the |
| 31 | * email address(es): |
| 32 | * lksctp developers <lksctp-developers@lists.sourceforge.net> |
| 33 | * |
| 34 | * Or submit a bug report through the following website: |
| 35 | * http://www.sf.net/projects/lksctp |
| 36 | * |
| 37 | * Written or modified by: |
| 38 | * La Monte H.P. Yarroll <piggy@acm.org> |
| 39 | * Karl Knutson <karl@athena.chicago.il.us> |
| 40 | * C. Robin <chris@hundredacre.ac.uk> |
| 41 | * Jon Grimm <jgrimm@us.ibm.com> |
| 42 | * Xingang Guo <xingang.guo@intel.com> |
| 43 | * Dajiang Zhang <dajiang.zhang@nokia.com> |
| 44 | * Sridhar Samudrala <sri@us.ibm.com> |
| 45 | * Daisy Chang <daisyc@us.ibm.com> |
| 46 | * Ardelle Fan <ardelle.fan@intel.com> |
| 47 | * Kevin Gao <kevin.gao@intel.com> |
| 48 | * |
| 49 | * Any bugs reported given to us we will try to fix... any fixes shared will |
| 50 | * be incorporated into the next SCTP release. |
| 51 | */ |
| 52 | |
| 53 | #include <linux/types.h> |
| 54 | #include <linux/kernel.h> |
| 55 | #include <linux/ip.h> |
| 56 | #include <linux/ipv6.h> |
| 57 | #include <linux/net.h> |
| 58 | #include <linux/inet.h> |
| 59 | #include <asm/scatterlist.h> |
| 60 | #include <linux/crypto.h> |
| 61 | #include <net/sock.h> |
| 62 | |
| 63 | #include <linux/skbuff.h> |
| 64 | #include <linux/random.h> /* for get_random_bytes */ |
| 65 | #include <net/sctp/sctp.h> |
| 66 | #include <net/sctp/sm.h> |
| 67 | |
| 68 | extern kmem_cache_t *sctp_chunk_cachep; |
| 69 | |
| 70 | SCTP_STATIC |
| 71 | struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc, |
| 72 | __u8 type, __u8 flags, int paylen); |
| 73 | static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep, |
| 74 | const struct sctp_association *asoc, |
| 75 | const struct sctp_chunk *init_chunk, |
| 76 | int *cookie_len, |
| 77 | const __u8 *raw_addrs, int addrs_len); |
| 78 | static int sctp_process_param(struct sctp_association *asoc, |
| 79 | union sctp_params param, |
| 80 | const union sctp_addr *peer_addr, |
| 81 | int gfp); |
| 82 | |
| 83 | /* What was the inbound interface for this chunk? */ |
| 84 | int sctp_chunk_iif(const struct sctp_chunk *chunk) |
| 85 | { |
| 86 | struct sctp_af *af; |
| 87 | int iif = 0; |
| 88 | |
| 89 | af = sctp_get_af_specific(ipver2af(chunk->skb->nh.iph->version)); |
| 90 | if (af) |
| 91 | iif = af->skb_iif(chunk->skb); |
| 92 | |
| 93 | return iif; |
| 94 | } |
| 95 | |
| 96 | /* RFC 2960 3.3.2 Initiation (INIT) (1) |
| 97 | * |
| 98 | * Note 2: The ECN capable field is reserved for future use of |
| 99 | * Explicit Congestion Notification. |
| 100 | */ |
| 101 | static const struct sctp_paramhdr ecap_param = { |
| 102 | SCTP_PARAM_ECN_CAPABLE, |
| 103 | __constant_htons(sizeof(struct sctp_paramhdr)), |
| 104 | }; |
| 105 | static const struct sctp_paramhdr prsctp_param = { |
| 106 | SCTP_PARAM_FWD_TSN_SUPPORT, |
| 107 | __constant_htons(sizeof(struct sctp_paramhdr)), |
| 108 | }; |
| 109 | |
| 110 | /* A helper to initialize to initialize an op error inside a |
| 111 | * provided chunk, as most cause codes will be embedded inside an |
| 112 | * abort chunk. |
| 113 | */ |
| 114 | void sctp_init_cause(struct sctp_chunk *chunk, __u16 cause_code, |
| 115 | const void *payload, size_t paylen) |
| 116 | { |
| 117 | sctp_errhdr_t err; |
| 118 | int padlen; |
| 119 | __u16 len; |
| 120 | |
| 121 | /* Cause code constants are now defined in network order. */ |
| 122 | err.cause = cause_code; |
| 123 | len = sizeof(sctp_errhdr_t) + paylen; |
| 124 | padlen = len % 4; |
| 125 | err.length = htons(len); |
| 126 | len += padlen; |
| 127 | sctp_addto_chunk(chunk, sizeof(sctp_errhdr_t), &err); |
| 128 | chunk->subh.err_hdr = sctp_addto_chunk(chunk, paylen, payload); |
| 129 | } |
| 130 | |
| 131 | /* 3.3.2 Initiation (INIT) (1) |
| 132 | * |
| 133 | * This chunk is used to initiate a SCTP association between two |
| 134 | * endpoints. The format of the INIT chunk is shown below: |
| 135 | * |
| 136 | * 0 1 2 3 |
| 137 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 138 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 139 | * | Type = 1 | Chunk Flags | Chunk Length | |
| 140 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 141 | * | Initiate Tag | |
| 142 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 143 | * | Advertised Receiver Window Credit (a_rwnd) | |
| 144 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 145 | * | Number of Outbound Streams | Number of Inbound Streams | |
| 146 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 147 | * | Initial TSN | |
| 148 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 149 | * \ \ |
| 150 | * / Optional/Variable-Length Parameters / |
| 151 | * \ \ |
| 152 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 153 | * |
| 154 | * |
| 155 | * The INIT chunk contains the following parameters. Unless otherwise |
| 156 | * noted, each parameter MUST only be included once in the INIT chunk. |
| 157 | * |
| 158 | * Fixed Parameters Status |
| 159 | * ---------------------------------------------- |
| 160 | * Initiate Tag Mandatory |
| 161 | * Advertised Receiver Window Credit Mandatory |
| 162 | * Number of Outbound Streams Mandatory |
| 163 | * Number of Inbound Streams Mandatory |
| 164 | * Initial TSN Mandatory |
| 165 | * |
| 166 | * Variable Parameters Status Type Value |
| 167 | * ------------------------------------------------------------- |
| 168 | * IPv4 Address (Note 1) Optional 5 |
| 169 | * IPv6 Address (Note 1) Optional 6 |
| 170 | * Cookie Preservative Optional 9 |
| 171 | * Reserved for ECN Capable (Note 2) Optional 32768 (0x8000) |
| 172 | * Host Name Address (Note 3) Optional 11 |
| 173 | * Supported Address Types (Note 4) Optional 12 |
| 174 | */ |
| 175 | struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, |
| 176 | const struct sctp_bind_addr *bp, |
| 177 | int gfp, int vparam_len) |
| 178 | { |
| 179 | sctp_inithdr_t init; |
| 180 | union sctp_params addrs; |
| 181 | size_t chunksize; |
| 182 | struct sctp_chunk *retval = NULL; |
| 183 | int num_types, addrs_len = 0; |
| 184 | struct sctp_sock *sp; |
| 185 | sctp_supported_addrs_param_t sat; |
| 186 | __u16 types[2]; |
| 187 | sctp_adaption_ind_param_t aiparam; |
| 188 | |
| 189 | /* RFC 2960 3.3.2 Initiation (INIT) (1) |
| 190 | * |
| 191 | * Note 1: The INIT chunks can contain multiple addresses that |
| 192 | * can be IPv4 and/or IPv6 in any combination. |
| 193 | */ |
| 194 | retval = NULL; |
| 195 | |
| 196 | /* Convert the provided bind address list to raw format. */ |
| 197 | addrs = sctp_bind_addrs_to_raw(bp, &addrs_len, gfp); |
| 198 | |
| 199 | init.init_tag = htonl(asoc->c.my_vtag); |
| 200 | init.a_rwnd = htonl(asoc->rwnd); |
| 201 | init.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); |
| 202 | init.num_inbound_streams = htons(asoc->c.sinit_max_instreams); |
| 203 | init.initial_tsn = htonl(asoc->c.initial_tsn); |
| 204 | |
| 205 | /* How many address types are needed? */ |
| 206 | sp = sctp_sk(asoc->base.sk); |
| 207 | num_types = sp->pf->supported_addrs(sp, types); |
| 208 | |
| 209 | chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types); |
| 210 | chunksize += sizeof(ecap_param); |
| 211 | if (sctp_prsctp_enable) |
| 212 | chunksize += sizeof(prsctp_param); |
| 213 | chunksize += sizeof(aiparam); |
| 214 | chunksize += vparam_len; |
| 215 | |
| 216 | /* RFC 2960 3.3.2 Initiation (INIT) (1) |
| 217 | * |
| 218 | * Note 3: An INIT chunk MUST NOT contain more than one Host |
| 219 | * Name address parameter. Moreover, the sender of the INIT |
| 220 | * MUST NOT combine any other address types with the Host Name |
| 221 | * address in the INIT. The receiver of INIT MUST ignore any |
| 222 | * other address types if the Host Name address parameter is |
| 223 | * present in the received INIT chunk. |
| 224 | * |
| 225 | * PLEASE DO NOT FIXME [This version does not support Host Name.] |
| 226 | */ |
| 227 | |
| 228 | retval = sctp_make_chunk(asoc, SCTP_CID_INIT, 0, chunksize); |
| 229 | if (!retval) |
| 230 | goto nodata; |
| 231 | |
| 232 | retval->subh.init_hdr = |
| 233 | sctp_addto_chunk(retval, sizeof(init), &init); |
| 234 | retval->param_hdr.v = |
| 235 | sctp_addto_chunk(retval, addrs_len, addrs.v); |
| 236 | |
| 237 | /* RFC 2960 3.3.2 Initiation (INIT) (1) |
| 238 | * |
| 239 | * Note 4: This parameter, when present, specifies all the |
| 240 | * address types the sending endpoint can support. The absence |
| 241 | * of this parameter indicates that the sending endpoint can |
| 242 | * support any address type. |
| 243 | */ |
| 244 | sat.param_hdr.type = SCTP_PARAM_SUPPORTED_ADDRESS_TYPES; |
| 245 | sat.param_hdr.length = htons(SCTP_SAT_LEN(num_types)); |
| 246 | sctp_addto_chunk(retval, sizeof(sat), &sat); |
| 247 | sctp_addto_chunk(retval, num_types * sizeof(__u16), &types); |
| 248 | |
| 249 | sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); |
| 250 | if (sctp_prsctp_enable) |
| 251 | sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); |
| 252 | aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND; |
| 253 | aiparam.param_hdr.length = htons(sizeof(aiparam)); |
| 254 | aiparam.adaption_ind = htonl(sp->adaption_ind); |
| 255 | sctp_addto_chunk(retval, sizeof(aiparam), &aiparam); |
| 256 | nodata: |
| 257 | if (addrs.v) |
| 258 | kfree(addrs.v); |
| 259 | return retval; |
| 260 | } |
| 261 | |
| 262 | struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, |
| 263 | const struct sctp_chunk *chunk, |
| 264 | int gfp, int unkparam_len) |
| 265 | { |
| 266 | sctp_inithdr_t initack; |
| 267 | struct sctp_chunk *retval; |
| 268 | union sctp_params addrs; |
| 269 | int addrs_len; |
| 270 | sctp_cookie_param_t *cookie; |
| 271 | int cookie_len; |
| 272 | size_t chunksize; |
| 273 | sctp_adaption_ind_param_t aiparam; |
| 274 | |
| 275 | retval = NULL; |
| 276 | |
| 277 | /* Note: there may be no addresses to embed. */ |
| 278 | addrs = sctp_bind_addrs_to_raw(&asoc->base.bind_addr, &addrs_len, gfp); |
| 279 | |
| 280 | initack.init_tag = htonl(asoc->c.my_vtag); |
| 281 | initack.a_rwnd = htonl(asoc->rwnd); |
| 282 | initack.num_outbound_streams = htons(asoc->c.sinit_num_ostreams); |
| 283 | initack.num_inbound_streams = htons(asoc->c.sinit_max_instreams); |
| 284 | initack.initial_tsn = htonl(asoc->c.initial_tsn); |
| 285 | |
| 286 | /* FIXME: We really ought to build the cookie right |
| 287 | * into the packet instead of allocating more fresh memory. |
| 288 | */ |
| 289 | cookie = sctp_pack_cookie(asoc->ep, asoc, chunk, &cookie_len, |
| 290 | addrs.v, addrs_len); |
| 291 | if (!cookie) |
| 292 | goto nomem_cookie; |
| 293 | |
| 294 | /* Calculate the total size of allocation, include the reserved |
| 295 | * space for reporting unknown parameters if it is specified. |
| 296 | */ |
| 297 | chunksize = sizeof(initack) + addrs_len + cookie_len + unkparam_len; |
| 298 | |
| 299 | /* Tell peer that we'll do ECN only if peer advertised such cap. */ |
| 300 | if (asoc->peer.ecn_capable) |
| 301 | chunksize += sizeof(ecap_param); |
| 302 | |
| 303 | /* Tell peer that we'll do PR-SCTP only if peer advertised. */ |
| 304 | if (asoc->peer.prsctp_capable) |
| 305 | chunksize += sizeof(prsctp_param); |
| 306 | |
| 307 | chunksize += sizeof(aiparam); |
| 308 | |
| 309 | /* Now allocate and fill out the chunk. */ |
| 310 | retval = sctp_make_chunk(asoc, SCTP_CID_INIT_ACK, 0, chunksize); |
| 311 | if (!retval) |
| 312 | goto nomem_chunk; |
| 313 | |
| 314 | /* Per the advice in RFC 2960 6.4, send this reply to |
| 315 | * the source of the INIT packet. |
| 316 | */ |
| 317 | retval->transport = chunk->transport; |
| 318 | retval->subh.init_hdr = |
| 319 | sctp_addto_chunk(retval, sizeof(initack), &initack); |
| 320 | retval->param_hdr.v = sctp_addto_chunk(retval, addrs_len, addrs.v); |
| 321 | sctp_addto_chunk(retval, cookie_len, cookie); |
| 322 | if (asoc->peer.ecn_capable) |
| 323 | sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); |
| 324 | if (asoc->peer.prsctp_capable) |
| 325 | sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); |
| 326 | |
| 327 | aiparam.param_hdr.type = SCTP_PARAM_ADAPTION_LAYER_IND; |
| 328 | aiparam.param_hdr.length = htons(sizeof(aiparam)); |
| 329 | aiparam.adaption_ind = htonl(sctp_sk(asoc->base.sk)->adaption_ind); |
| 330 | sctp_addto_chunk(retval, sizeof(aiparam), &aiparam); |
| 331 | |
| 332 | /* We need to remove the const qualifier at this point. */ |
| 333 | retval->asoc = (struct sctp_association *) asoc; |
| 334 | |
| 335 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 336 | * |
| 337 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 338 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 339 | * address from which it received the DATA or control chunk |
| 340 | * to which it is replying. |
| 341 | * |
| 342 | * [INIT ACK back to where the INIT came from.] |
| 343 | */ |
| 344 | if (chunk) |
| 345 | retval->transport = chunk->transport; |
| 346 | |
| 347 | nomem_chunk: |
| 348 | kfree(cookie); |
| 349 | nomem_cookie: |
| 350 | if (addrs.v) |
| 351 | kfree(addrs.v); |
| 352 | return retval; |
| 353 | } |
| 354 | |
| 355 | /* 3.3.11 Cookie Echo (COOKIE ECHO) (10): |
| 356 | * |
| 357 | * This chunk is used only during the initialization of an association. |
| 358 | * It is sent by the initiator of an association to its peer to complete |
| 359 | * the initialization process. This chunk MUST precede any DATA chunk |
| 360 | * sent within the association, but MAY be bundled with one or more DATA |
| 361 | * chunks in the same packet. |
| 362 | * |
| 363 | * 0 1 2 3 |
| 364 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 365 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 366 | * | Type = 10 |Chunk Flags | Length | |
| 367 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 368 | * / Cookie / |
| 369 | * \ \ |
| 370 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 371 | * |
| 372 | * Chunk Flags: 8 bit |
| 373 | * |
| 374 | * Set to zero on transmit and ignored on receipt. |
| 375 | * |
| 376 | * Length: 16 bits (unsigned integer) |
| 377 | * |
| 378 | * Set to the size of the chunk in bytes, including the 4 bytes of |
| 379 | * the chunk header and the size of the Cookie. |
| 380 | * |
| 381 | * Cookie: variable size |
| 382 | * |
| 383 | * This field must contain the exact cookie received in the |
| 384 | * State Cookie parameter from the previous INIT ACK. |
| 385 | * |
| 386 | * An implementation SHOULD make the cookie as small as possible |
| 387 | * to insure interoperability. |
| 388 | */ |
| 389 | struct sctp_chunk *sctp_make_cookie_echo(const struct sctp_association *asoc, |
| 390 | const struct sctp_chunk *chunk) |
| 391 | { |
| 392 | struct sctp_chunk *retval; |
| 393 | void *cookie; |
| 394 | int cookie_len; |
| 395 | |
| 396 | cookie = asoc->peer.cookie; |
| 397 | cookie_len = asoc->peer.cookie_len; |
| 398 | |
| 399 | /* Build a cookie echo chunk. */ |
| 400 | retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ECHO, 0, cookie_len); |
| 401 | if (!retval) |
| 402 | goto nodata; |
| 403 | retval->subh.cookie_hdr = |
| 404 | sctp_addto_chunk(retval, cookie_len, cookie); |
| 405 | |
| 406 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 407 | * |
| 408 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 409 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 410 | * address from which it * received the DATA or control chunk |
| 411 | * to which it is replying. |
| 412 | * |
| 413 | * [COOKIE ECHO back to where the INIT ACK came from.] |
| 414 | */ |
| 415 | if (chunk) |
| 416 | retval->transport = chunk->transport; |
| 417 | |
| 418 | nodata: |
| 419 | return retval; |
| 420 | } |
| 421 | |
| 422 | /* 3.3.12 Cookie Acknowledgement (COOKIE ACK) (11): |
| 423 | * |
| 424 | * This chunk is used only during the initialization of an |
| 425 | * association. It is used to acknowledge the receipt of a COOKIE |
| 426 | * ECHO chunk. This chunk MUST precede any DATA or SACK chunk sent |
| 427 | * within the association, but MAY be bundled with one or more DATA |
| 428 | * chunks or SACK chunk in the same SCTP packet. |
| 429 | * |
| 430 | * 0 1 2 3 |
| 431 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 432 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 433 | * | Type = 11 |Chunk Flags | Length = 4 | |
| 434 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 435 | * |
| 436 | * Chunk Flags: 8 bits |
| 437 | * |
| 438 | * Set to zero on transmit and ignored on receipt. |
| 439 | */ |
| 440 | struct sctp_chunk *sctp_make_cookie_ack(const struct sctp_association *asoc, |
| 441 | const struct sctp_chunk *chunk) |
| 442 | { |
| 443 | struct sctp_chunk *retval; |
| 444 | |
| 445 | retval = sctp_make_chunk(asoc, SCTP_CID_COOKIE_ACK, 0, 0); |
| 446 | |
| 447 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 448 | * |
| 449 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 450 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 451 | * address from which it * received the DATA or control chunk |
| 452 | * to which it is replying. |
| 453 | * |
| 454 | * [COOKIE ACK back to where the COOKIE ECHO came from.] |
| 455 | */ |
| 456 | if (retval && chunk) |
| 457 | retval->transport = chunk->transport; |
| 458 | |
| 459 | return retval; |
| 460 | } |
| 461 | |
| 462 | /* |
| 463 | * Appendix A: Explicit Congestion Notification: |
| 464 | * CWR: |
| 465 | * |
| 466 | * RFC 2481 details a specific bit for a sender to send in the header of |
| 467 | * its next outbound TCP segment to indicate to its peer that it has |
| 468 | * reduced its congestion window. This is termed the CWR bit. For |
| 469 | * SCTP the same indication is made by including the CWR chunk. |
| 470 | * This chunk contains one data element, i.e. the TSN number that |
| 471 | * was sent in the ECNE chunk. This element represents the lowest |
| 472 | * TSN number in the datagram that was originally marked with the |
| 473 | * CE bit. |
| 474 | * |
| 475 | * 0 1 2 3 |
| 476 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 477 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 478 | * | Chunk Type=13 | Flags=00000000| Chunk Length = 8 | |
| 479 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 480 | * | Lowest TSN Number | |
| 481 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 482 | * |
| 483 | * Note: The CWR is considered a Control chunk. |
| 484 | */ |
| 485 | struct sctp_chunk *sctp_make_cwr(const struct sctp_association *asoc, |
| 486 | const __u32 lowest_tsn, |
| 487 | const struct sctp_chunk *chunk) |
| 488 | { |
| 489 | struct sctp_chunk *retval; |
| 490 | sctp_cwrhdr_t cwr; |
| 491 | |
| 492 | cwr.lowest_tsn = htonl(lowest_tsn); |
| 493 | retval = sctp_make_chunk(asoc, SCTP_CID_ECN_CWR, 0, |
| 494 | sizeof(sctp_cwrhdr_t)); |
| 495 | |
| 496 | if (!retval) |
| 497 | goto nodata; |
| 498 | |
| 499 | retval->subh.ecn_cwr_hdr = |
| 500 | sctp_addto_chunk(retval, sizeof(cwr), &cwr); |
| 501 | |
| 502 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 503 | * |
| 504 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 505 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 506 | * address from which it * received the DATA or control chunk |
| 507 | * to which it is replying. |
| 508 | * |
| 509 | * [Report a reduced congestion window back to where the ECNE |
| 510 | * came from.] |
| 511 | */ |
| 512 | if (chunk) |
| 513 | retval->transport = chunk->transport; |
| 514 | |
| 515 | nodata: |
| 516 | return retval; |
| 517 | } |
| 518 | |
| 519 | /* Make an ECNE chunk. This is a congestion experienced report. */ |
| 520 | struct sctp_chunk *sctp_make_ecne(const struct sctp_association *asoc, |
| 521 | const __u32 lowest_tsn) |
| 522 | { |
| 523 | struct sctp_chunk *retval; |
| 524 | sctp_ecnehdr_t ecne; |
| 525 | |
| 526 | ecne.lowest_tsn = htonl(lowest_tsn); |
| 527 | retval = sctp_make_chunk(asoc, SCTP_CID_ECN_ECNE, 0, |
| 528 | sizeof(sctp_ecnehdr_t)); |
| 529 | if (!retval) |
| 530 | goto nodata; |
| 531 | retval->subh.ecne_hdr = |
| 532 | sctp_addto_chunk(retval, sizeof(ecne), &ecne); |
| 533 | |
| 534 | nodata: |
| 535 | return retval; |
| 536 | } |
| 537 | |
| 538 | /* Make a DATA chunk for the given association from the provided |
| 539 | * parameters. However, do not populate the data payload. |
| 540 | */ |
| 541 | struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc, |
| 542 | const struct sctp_sndrcvinfo *sinfo, |
| 543 | int data_len, __u8 flags, __u16 ssn) |
| 544 | { |
| 545 | struct sctp_chunk *retval; |
| 546 | struct sctp_datahdr dp; |
| 547 | int chunk_len; |
| 548 | |
| 549 | /* We assign the TSN as LATE as possible, not here when |
| 550 | * creating the chunk. |
| 551 | */ |
| 552 | dp.tsn = 0; |
| 553 | dp.stream = htons(sinfo->sinfo_stream); |
| 554 | dp.ppid = sinfo->sinfo_ppid; |
| 555 | |
| 556 | /* Set the flags for an unordered send. */ |
| 557 | if (sinfo->sinfo_flags & MSG_UNORDERED) { |
| 558 | flags |= SCTP_DATA_UNORDERED; |
| 559 | dp.ssn = 0; |
| 560 | } else |
| 561 | dp.ssn = htons(ssn); |
| 562 | |
| 563 | chunk_len = sizeof(dp) + data_len; |
| 564 | retval = sctp_make_chunk(asoc, SCTP_CID_DATA, flags, chunk_len); |
| 565 | if (!retval) |
| 566 | goto nodata; |
| 567 | |
| 568 | retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp); |
| 569 | memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo)); |
| 570 | |
| 571 | nodata: |
| 572 | return retval; |
| 573 | } |
| 574 | |
| 575 | /* Create a selective ackowledgement (SACK) for the given |
| 576 | * association. This reports on which TSN's we've seen to date, |
| 577 | * including duplicates and gaps. |
| 578 | */ |
| 579 | struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc) |
| 580 | { |
| 581 | struct sctp_chunk *retval; |
| 582 | struct sctp_sackhdr sack; |
| 583 | int len; |
| 584 | __u32 ctsn; |
| 585 | __u16 num_gabs, num_dup_tsns; |
| 586 | struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map; |
| 587 | |
| 588 | ctsn = sctp_tsnmap_get_ctsn(map); |
| 589 | SCTP_DEBUG_PRINTK("sackCTSNAck sent: 0x%x.\n", ctsn); |
| 590 | |
| 591 | /* How much room is needed in the chunk? */ |
| 592 | num_gabs = sctp_tsnmap_num_gabs(map); |
| 593 | num_dup_tsns = sctp_tsnmap_num_dups(map); |
| 594 | |
| 595 | /* Initialize the SACK header. */ |
| 596 | sack.cum_tsn_ack = htonl(ctsn); |
| 597 | sack.a_rwnd = htonl(asoc->a_rwnd); |
| 598 | sack.num_gap_ack_blocks = htons(num_gabs); |
| 599 | sack.num_dup_tsns = htons(num_dup_tsns); |
| 600 | |
| 601 | len = sizeof(sack) |
| 602 | + sizeof(struct sctp_gap_ack_block) * num_gabs |
| 603 | + sizeof(__u32) * num_dup_tsns; |
| 604 | |
| 605 | /* Create the chunk. */ |
| 606 | retval = sctp_make_chunk(asoc, SCTP_CID_SACK, 0, len); |
| 607 | if (!retval) |
| 608 | goto nodata; |
| 609 | |
| 610 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 611 | * |
| 612 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 613 | * HEARTBEAT ACK, etc.) to the same destination transport |
| 614 | * address from which it received the DATA or control chunk to |
| 615 | * which it is replying. This rule should also be followed if |
| 616 | * the endpoint is bundling DATA chunks together with the |
| 617 | * reply chunk. |
| 618 | * |
| 619 | * However, when acknowledging multiple DATA chunks received |
| 620 | * in packets from different source addresses in a single |
| 621 | * SACK, the SACK chunk may be transmitted to one of the |
| 622 | * destination transport addresses from which the DATA or |
| 623 | * control chunks being acknowledged were received. |
| 624 | * |
| 625 | * [BUG: We do not implement the following paragraph. |
| 626 | * Perhaps we should remember the last transport we used for a |
| 627 | * SACK and avoid that (if possible) if we have seen any |
| 628 | * duplicates. --piggy] |
| 629 | * |
| 630 | * When a receiver of a duplicate DATA chunk sends a SACK to a |
| 631 | * multi- homed endpoint it MAY be beneficial to vary the |
| 632 | * destination address and not use the source address of the |
| 633 | * DATA chunk. The reason being that receiving a duplicate |
| 634 | * from a multi-homed endpoint might indicate that the return |
| 635 | * path (as specified in the source address of the DATA chunk) |
| 636 | * for the SACK is broken. |
| 637 | * |
| 638 | * [Send to the address from which we last received a DATA chunk.] |
| 639 | */ |
| 640 | retval->transport = asoc->peer.last_data_from; |
| 641 | |
| 642 | retval->subh.sack_hdr = |
| 643 | sctp_addto_chunk(retval, sizeof(sack), &sack); |
| 644 | |
| 645 | /* Add the gap ack block information. */ |
| 646 | if (num_gabs) |
| 647 | sctp_addto_chunk(retval, sizeof(__u32) * num_gabs, |
| 648 | sctp_tsnmap_get_gabs(map)); |
| 649 | |
| 650 | /* Add the duplicate TSN information. */ |
| 651 | if (num_dup_tsns) |
| 652 | sctp_addto_chunk(retval, sizeof(__u32) * num_dup_tsns, |
| 653 | sctp_tsnmap_get_dups(map)); |
| 654 | |
| 655 | nodata: |
| 656 | return retval; |
| 657 | } |
| 658 | |
| 659 | /* Make a SHUTDOWN chunk. */ |
| 660 | struct sctp_chunk *sctp_make_shutdown(const struct sctp_association *asoc, |
| 661 | const struct sctp_chunk *chunk) |
| 662 | { |
| 663 | struct sctp_chunk *retval; |
| 664 | sctp_shutdownhdr_t shut; |
| 665 | __u32 ctsn; |
| 666 | |
| 667 | ctsn = sctp_tsnmap_get_ctsn(&asoc->peer.tsn_map); |
| 668 | shut.cum_tsn_ack = htonl(ctsn); |
| 669 | |
| 670 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN, 0, |
| 671 | sizeof(sctp_shutdownhdr_t)); |
| 672 | if (!retval) |
| 673 | goto nodata; |
| 674 | |
| 675 | retval->subh.shutdown_hdr = |
| 676 | sctp_addto_chunk(retval, sizeof(shut), &shut); |
| 677 | |
| 678 | if (chunk) |
| 679 | retval->transport = chunk->transport; |
| 680 | nodata: |
| 681 | return retval; |
| 682 | } |
| 683 | |
| 684 | struct sctp_chunk *sctp_make_shutdown_ack(const struct sctp_association *asoc, |
| 685 | const struct sctp_chunk *chunk) |
| 686 | { |
| 687 | struct sctp_chunk *retval; |
| 688 | |
| 689 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_ACK, 0, 0); |
| 690 | |
| 691 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 692 | * |
| 693 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 694 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 695 | * address from which it * received the DATA or control chunk |
| 696 | * to which it is replying. |
| 697 | * |
| 698 | * [ACK back to where the SHUTDOWN came from.] |
| 699 | */ |
| 700 | if (retval && chunk) |
| 701 | retval->transport = chunk->transport; |
| 702 | |
| 703 | return retval; |
| 704 | } |
| 705 | |
| 706 | struct sctp_chunk *sctp_make_shutdown_complete( |
| 707 | const struct sctp_association *asoc, |
| 708 | const struct sctp_chunk *chunk) |
| 709 | { |
| 710 | struct sctp_chunk *retval; |
| 711 | __u8 flags = 0; |
| 712 | |
Jerome Forissier | 047a242 | 2005-04-28 11:58:43 -0700 | [diff] [blame] | 713 | /* Set the T-bit if we have no association (vtag will be |
| 714 | * reflected) |
| 715 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | flags |= asoc ? 0 : SCTP_CHUNK_FLAG_T; |
| 717 | |
| 718 | retval = sctp_make_chunk(asoc, SCTP_CID_SHUTDOWN_COMPLETE, flags, 0); |
| 719 | |
| 720 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 721 | * |
| 722 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 723 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 724 | * address from which it * received the DATA or control chunk |
| 725 | * to which it is replying. |
| 726 | * |
| 727 | * [Report SHUTDOWN COMPLETE back to where the SHUTDOWN ACK |
| 728 | * came from.] |
| 729 | */ |
| 730 | if (retval && chunk) |
| 731 | retval->transport = chunk->transport; |
| 732 | |
| 733 | return retval; |
| 734 | } |
| 735 | |
| 736 | /* Create an ABORT. Note that we set the T bit if we have no |
Jerome Forissier | 047a242 | 2005-04-28 11:58:43 -0700 | [diff] [blame] | 737 | * association, except when responding to an INIT (sctpimpguide 2.41). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 738 | */ |
| 739 | struct sctp_chunk *sctp_make_abort(const struct sctp_association *asoc, |
| 740 | const struct sctp_chunk *chunk, |
| 741 | const size_t hint) |
| 742 | { |
| 743 | struct sctp_chunk *retval; |
| 744 | __u8 flags = 0; |
| 745 | |
Jerome Forissier | 047a242 | 2005-04-28 11:58:43 -0700 | [diff] [blame] | 746 | /* Set the T-bit if we have no association and 'chunk' is not |
| 747 | * an INIT (vtag will be reflected). |
| 748 | */ |
| 749 | if (!asoc) { |
| 750 | if (chunk && chunk->chunk_hdr && |
| 751 | chunk->chunk_hdr->type == SCTP_CID_INIT) |
| 752 | flags = 0; |
| 753 | else |
| 754 | flags = SCTP_CHUNK_FLAG_T; |
| 755 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | |
| 757 | retval = sctp_make_chunk(asoc, SCTP_CID_ABORT, flags, hint); |
| 758 | |
| 759 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 760 | * |
| 761 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 762 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 763 | * address from which it * received the DATA or control chunk |
| 764 | * to which it is replying. |
| 765 | * |
| 766 | * [ABORT back to where the offender came from.] |
| 767 | */ |
| 768 | if (retval && chunk) |
| 769 | retval->transport = chunk->transport; |
| 770 | |
| 771 | return retval; |
| 772 | } |
| 773 | |
| 774 | /* Helper to create ABORT with a NO_USER_DATA error. */ |
| 775 | struct sctp_chunk *sctp_make_abort_no_data( |
| 776 | const struct sctp_association *asoc, |
| 777 | const struct sctp_chunk *chunk, __u32 tsn) |
| 778 | { |
| 779 | struct sctp_chunk *retval; |
| 780 | __u32 payload; |
| 781 | |
| 782 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) |
| 783 | + sizeof(tsn)); |
| 784 | |
| 785 | if (!retval) |
| 786 | goto no_mem; |
| 787 | |
| 788 | /* Put the tsn back into network byte order. */ |
| 789 | payload = htonl(tsn); |
| 790 | sctp_init_cause(retval, SCTP_ERROR_NO_DATA, (const void *)&payload, |
| 791 | sizeof(payload)); |
| 792 | |
| 793 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 794 | * |
| 795 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 796 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 797 | * address from which it * received the DATA or control chunk |
| 798 | * to which it is replying. |
| 799 | * |
| 800 | * [ABORT back to where the offender came from.] |
| 801 | */ |
| 802 | if (chunk) |
| 803 | retval->transport = chunk->transport; |
| 804 | |
| 805 | no_mem: |
| 806 | return retval; |
| 807 | } |
| 808 | |
| 809 | /* Helper to create ABORT with a SCTP_ERROR_USER_ABORT error. */ |
| 810 | struct sctp_chunk *sctp_make_abort_user(const struct sctp_association *asoc, |
| 811 | const struct sctp_chunk *chunk, |
| 812 | const struct msghdr *msg) |
| 813 | { |
| 814 | struct sctp_chunk *retval; |
| 815 | void *payload = NULL, *payoff; |
| 816 | size_t paylen = 0; |
| 817 | struct iovec *iov = NULL; |
| 818 | int iovlen = 0; |
| 819 | |
| 820 | if (msg) { |
| 821 | iov = msg->msg_iov; |
| 822 | iovlen = msg->msg_iovlen; |
| 823 | paylen = get_user_iov_size(iov, iovlen); |
| 824 | } |
| 825 | |
| 826 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen); |
| 827 | if (!retval) |
| 828 | goto err_chunk; |
| 829 | |
| 830 | if (paylen) { |
| 831 | /* Put the msg_iov together into payload. */ |
| 832 | payload = kmalloc(paylen, GFP_ATOMIC); |
| 833 | if (!payload) |
| 834 | goto err_payload; |
| 835 | payoff = payload; |
| 836 | |
| 837 | for (; iovlen > 0; --iovlen) { |
| 838 | if (copy_from_user(payoff, iov->iov_base,iov->iov_len)) |
| 839 | goto err_copy; |
| 840 | payoff += iov->iov_len; |
| 841 | iov++; |
| 842 | } |
| 843 | } |
| 844 | |
| 845 | sctp_init_cause(retval, SCTP_ERROR_USER_ABORT, payload, paylen); |
| 846 | |
| 847 | if (paylen) |
| 848 | kfree(payload); |
| 849 | |
| 850 | return retval; |
| 851 | |
| 852 | err_copy: |
| 853 | kfree(payload); |
| 854 | err_payload: |
| 855 | sctp_chunk_free(retval); |
| 856 | retval = NULL; |
| 857 | err_chunk: |
| 858 | return retval; |
| 859 | } |
| 860 | |
| 861 | /* Make an ABORT chunk with a PROTOCOL VIOLATION cause code. */ |
| 862 | struct sctp_chunk *sctp_make_abort_violation( |
| 863 | const struct sctp_association *asoc, |
| 864 | const struct sctp_chunk *chunk, |
| 865 | const __u8 *payload, |
| 866 | const size_t paylen) |
| 867 | { |
| 868 | struct sctp_chunk *retval; |
| 869 | struct sctp_paramhdr phdr; |
| 870 | |
| 871 | retval = sctp_make_abort(asoc, chunk, sizeof(sctp_errhdr_t) + paylen |
| 872 | + sizeof(sctp_chunkhdr_t)); |
| 873 | if (!retval) |
| 874 | goto end; |
| 875 | |
| 876 | sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, payload, paylen); |
| 877 | |
| 878 | phdr.type = htons(chunk->chunk_hdr->type); |
| 879 | phdr.length = chunk->chunk_hdr->length; |
| 880 | sctp_addto_chunk(retval, sizeof(sctp_paramhdr_t), &phdr); |
| 881 | |
| 882 | end: |
| 883 | return retval; |
| 884 | } |
| 885 | |
| 886 | /* Make a HEARTBEAT chunk. */ |
| 887 | struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc, |
| 888 | const struct sctp_transport *transport, |
| 889 | const void *payload, const size_t paylen) |
| 890 | { |
| 891 | struct sctp_chunk *retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT, |
| 892 | 0, paylen); |
| 893 | |
| 894 | if (!retval) |
| 895 | goto nodata; |
| 896 | |
| 897 | /* Cast away the 'const', as this is just telling the chunk |
| 898 | * what transport it belongs to. |
| 899 | */ |
| 900 | retval->transport = (struct sctp_transport *) transport; |
| 901 | retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload); |
| 902 | |
| 903 | nodata: |
| 904 | return retval; |
| 905 | } |
| 906 | |
| 907 | struct sctp_chunk *sctp_make_heartbeat_ack(const struct sctp_association *asoc, |
| 908 | const struct sctp_chunk *chunk, |
| 909 | const void *payload, const size_t paylen) |
| 910 | { |
| 911 | struct sctp_chunk *retval; |
| 912 | |
| 913 | retval = sctp_make_chunk(asoc, SCTP_CID_HEARTBEAT_ACK, 0, paylen); |
| 914 | if (!retval) |
| 915 | goto nodata; |
| 916 | |
| 917 | retval->subh.hbs_hdr = sctp_addto_chunk(retval, paylen, payload); |
| 918 | |
| 919 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 920 | * |
| 921 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 922 | * HEARTBEAT ACK, * etc.) to the same destination transport |
| 923 | * address from which it * received the DATA or control chunk |
| 924 | * to which it is replying. |
| 925 | * |
| 926 | * [HBACK back to where the HEARTBEAT came from.] |
| 927 | */ |
| 928 | if (chunk) |
| 929 | retval->transport = chunk->transport; |
| 930 | |
| 931 | nodata: |
| 932 | return retval; |
| 933 | } |
| 934 | |
| 935 | /* Create an Operation Error chunk with the specified space reserved. |
| 936 | * This routine can be used for containing multiple causes in the chunk. |
| 937 | */ |
| 938 | static struct sctp_chunk *sctp_make_op_error_space( |
| 939 | const struct sctp_association *asoc, |
| 940 | const struct sctp_chunk *chunk, |
| 941 | size_t size) |
| 942 | { |
| 943 | struct sctp_chunk *retval; |
| 944 | |
| 945 | retval = sctp_make_chunk(asoc, SCTP_CID_ERROR, 0, |
| 946 | sizeof(sctp_errhdr_t) + size); |
| 947 | if (!retval) |
| 948 | goto nodata; |
| 949 | |
| 950 | /* RFC 2960 6.4 Multi-homed SCTP Endpoints |
| 951 | * |
| 952 | * An endpoint SHOULD transmit reply chunks (e.g., SACK, |
| 953 | * HEARTBEAT ACK, etc.) to the same destination transport |
| 954 | * address from which it received the DATA or control chunk |
| 955 | * to which it is replying. |
| 956 | * |
| 957 | */ |
| 958 | if (chunk) |
| 959 | retval->transport = chunk->transport; |
| 960 | |
| 961 | nodata: |
| 962 | return retval; |
| 963 | } |
| 964 | |
| 965 | /* Create an Operation Error chunk. */ |
| 966 | struct sctp_chunk *sctp_make_op_error(const struct sctp_association *asoc, |
| 967 | const struct sctp_chunk *chunk, |
| 968 | __u16 cause_code, const void *payload, |
| 969 | size_t paylen) |
| 970 | { |
| 971 | struct sctp_chunk *retval; |
| 972 | |
| 973 | retval = sctp_make_op_error_space(asoc, chunk, paylen); |
| 974 | if (!retval) |
| 975 | goto nodata; |
| 976 | |
| 977 | sctp_init_cause(retval, cause_code, payload, paylen); |
| 978 | |
| 979 | nodata: |
| 980 | return retval; |
| 981 | } |
| 982 | |
| 983 | /******************************************************************** |
| 984 | * 2nd Level Abstractions |
| 985 | ********************************************************************/ |
| 986 | |
| 987 | /* Turn an skb into a chunk. |
| 988 | * FIXME: Eventually move the structure directly inside the skb->cb[]. |
| 989 | */ |
| 990 | struct sctp_chunk *sctp_chunkify(struct sk_buff *skb, |
| 991 | const struct sctp_association *asoc, |
| 992 | struct sock *sk) |
| 993 | { |
| 994 | struct sctp_chunk *retval; |
| 995 | |
| 996 | retval = kmem_cache_alloc(sctp_chunk_cachep, SLAB_ATOMIC); |
| 997 | |
| 998 | if (!retval) |
| 999 | goto nodata; |
| 1000 | memset(retval, 0, sizeof(struct sctp_chunk)); |
| 1001 | |
| 1002 | if (!sk) { |
| 1003 | SCTP_DEBUG_PRINTK("chunkifying skb %p w/o an sk\n", skb); |
| 1004 | } |
| 1005 | |
| 1006 | retval->skb = skb; |
| 1007 | retval->asoc = (struct sctp_association *)asoc; |
| 1008 | retval->resent = 0; |
| 1009 | retval->has_tsn = 0; |
| 1010 | retval->has_ssn = 0; |
| 1011 | retval->rtt_in_progress = 0; |
| 1012 | retval->sent_at = 0; |
| 1013 | retval->singleton = 1; |
| 1014 | retval->end_of_packet = 0; |
| 1015 | retval->ecn_ce_done = 0; |
| 1016 | retval->pdiscard = 0; |
| 1017 | |
| 1018 | /* sctpimpguide-05.txt Section 2.8.2 |
| 1019 | * M1) Each time a new DATA chunk is transmitted |
| 1020 | * set the 'TSN.Missing.Report' count for that TSN to 0. The |
| 1021 | * 'TSN.Missing.Report' count will be used to determine missing chunks |
| 1022 | * and when to fast retransmit. |
| 1023 | */ |
| 1024 | retval->tsn_missing_report = 0; |
| 1025 | retval->tsn_gap_acked = 0; |
| 1026 | retval->fast_retransmit = 0; |
| 1027 | |
| 1028 | /* If this is a fragmented message, track all fragments |
| 1029 | * of the message (for SEND_FAILED). |
| 1030 | */ |
| 1031 | retval->msg = NULL; |
| 1032 | |
| 1033 | /* Polish the bead hole. */ |
| 1034 | INIT_LIST_HEAD(&retval->transmitted_list); |
| 1035 | INIT_LIST_HEAD(&retval->frag_list); |
| 1036 | SCTP_DBG_OBJCNT_INC(chunk); |
| 1037 | atomic_set(&retval->refcnt, 1); |
| 1038 | |
| 1039 | nodata: |
| 1040 | return retval; |
| 1041 | } |
| 1042 | |
| 1043 | /* Set chunk->source and dest based on the IP header in chunk->skb. */ |
| 1044 | void sctp_init_addrs(struct sctp_chunk *chunk, union sctp_addr *src, |
| 1045 | union sctp_addr *dest) |
| 1046 | { |
| 1047 | memcpy(&chunk->source, src, sizeof(union sctp_addr)); |
| 1048 | memcpy(&chunk->dest, dest, sizeof(union sctp_addr)); |
| 1049 | } |
| 1050 | |
| 1051 | /* Extract the source address from a chunk. */ |
| 1052 | const union sctp_addr *sctp_source(const struct sctp_chunk *chunk) |
| 1053 | { |
| 1054 | /* If we have a known transport, use that. */ |
| 1055 | if (chunk->transport) { |
| 1056 | return &chunk->transport->ipaddr; |
| 1057 | } else { |
| 1058 | /* Otherwise, extract it from the IP header. */ |
| 1059 | return &chunk->source; |
| 1060 | } |
| 1061 | } |
| 1062 | |
| 1063 | /* Create a new chunk, setting the type and flags headers from the |
| 1064 | * arguments, reserving enough space for a 'paylen' byte payload. |
| 1065 | */ |
| 1066 | SCTP_STATIC |
| 1067 | struct sctp_chunk *sctp_make_chunk(const struct sctp_association *asoc, |
| 1068 | __u8 type, __u8 flags, int paylen) |
| 1069 | { |
| 1070 | struct sctp_chunk *retval; |
| 1071 | sctp_chunkhdr_t *chunk_hdr; |
| 1072 | struct sk_buff *skb; |
| 1073 | struct sock *sk; |
| 1074 | |
| 1075 | /* No need to allocate LL here, as this is only a chunk. */ |
| 1076 | skb = alloc_skb(WORD_ROUND(sizeof(sctp_chunkhdr_t) + paylen), |
| 1077 | GFP_ATOMIC); |
| 1078 | if (!skb) |
| 1079 | goto nodata; |
| 1080 | |
| 1081 | /* Make room for the chunk header. */ |
| 1082 | chunk_hdr = (sctp_chunkhdr_t *)skb_put(skb, sizeof(sctp_chunkhdr_t)); |
| 1083 | chunk_hdr->type = type; |
| 1084 | chunk_hdr->flags = flags; |
| 1085 | chunk_hdr->length = htons(sizeof(sctp_chunkhdr_t)); |
| 1086 | |
| 1087 | sk = asoc ? asoc->base.sk : NULL; |
| 1088 | retval = sctp_chunkify(skb, asoc, sk); |
| 1089 | if (!retval) { |
| 1090 | kfree_skb(skb); |
| 1091 | goto nodata; |
| 1092 | } |
| 1093 | |
| 1094 | retval->chunk_hdr = chunk_hdr; |
| 1095 | retval->chunk_end = ((__u8 *)chunk_hdr) + sizeof(struct sctp_chunkhdr); |
| 1096 | |
| 1097 | /* Set the skb to the belonging sock for accounting. */ |
| 1098 | skb->sk = sk; |
| 1099 | |
| 1100 | return retval; |
| 1101 | nodata: |
| 1102 | return NULL; |
| 1103 | } |
| 1104 | |
| 1105 | |
| 1106 | /* Release the memory occupied by a chunk. */ |
| 1107 | static void sctp_chunk_destroy(struct sctp_chunk *chunk) |
| 1108 | { |
| 1109 | /* Free the chunk skb data and the SCTP_chunk stub itself. */ |
| 1110 | dev_kfree_skb(chunk->skb); |
| 1111 | |
| 1112 | SCTP_DBG_OBJCNT_DEC(chunk); |
| 1113 | kmem_cache_free(sctp_chunk_cachep, chunk); |
| 1114 | } |
| 1115 | |
| 1116 | /* Possibly, free the chunk. */ |
| 1117 | void sctp_chunk_free(struct sctp_chunk *chunk) |
| 1118 | { |
| 1119 | /* Make sure that we are not on any list. */ |
| 1120 | skb_unlink((struct sk_buff *) chunk); |
| 1121 | list_del_init(&chunk->transmitted_list); |
| 1122 | |
| 1123 | /* Release our reference on the message tracker. */ |
| 1124 | if (chunk->msg) |
| 1125 | sctp_datamsg_put(chunk->msg); |
| 1126 | |
| 1127 | sctp_chunk_put(chunk); |
| 1128 | } |
| 1129 | |
| 1130 | /* Grab a reference to the chunk. */ |
| 1131 | void sctp_chunk_hold(struct sctp_chunk *ch) |
| 1132 | { |
| 1133 | atomic_inc(&ch->refcnt); |
| 1134 | } |
| 1135 | |
| 1136 | /* Release a reference to the chunk. */ |
| 1137 | void sctp_chunk_put(struct sctp_chunk *ch) |
| 1138 | { |
| 1139 | if (atomic_dec_and_test(&ch->refcnt)) |
| 1140 | sctp_chunk_destroy(ch); |
| 1141 | } |
| 1142 | |
| 1143 | /* Append bytes to the end of a chunk. Will panic if chunk is not big |
| 1144 | * enough. |
| 1145 | */ |
| 1146 | void *sctp_addto_chunk(struct sctp_chunk *chunk, int len, const void *data) |
| 1147 | { |
| 1148 | void *target; |
| 1149 | void *padding; |
| 1150 | int chunklen = ntohs(chunk->chunk_hdr->length); |
| 1151 | int padlen = chunklen % 4; |
| 1152 | |
| 1153 | padding = skb_put(chunk->skb, padlen); |
| 1154 | target = skb_put(chunk->skb, len); |
| 1155 | |
| 1156 | memset(padding, 0, padlen); |
| 1157 | memcpy(target, data, len); |
| 1158 | |
| 1159 | /* Adjust the chunk length field. */ |
| 1160 | chunk->chunk_hdr->length = htons(chunklen + padlen + len); |
| 1161 | chunk->chunk_end = chunk->skb->tail; |
| 1162 | |
| 1163 | return target; |
| 1164 | } |
| 1165 | |
| 1166 | /* Append bytes from user space to the end of a chunk. Will panic if |
| 1167 | * chunk is not big enough. |
| 1168 | * Returns a kernel err value. |
| 1169 | */ |
| 1170 | int sctp_user_addto_chunk(struct sctp_chunk *chunk, int off, int len, |
| 1171 | struct iovec *data) |
| 1172 | { |
| 1173 | __u8 *target; |
| 1174 | int err = 0; |
| 1175 | |
| 1176 | /* Make room in chunk for data. */ |
| 1177 | target = skb_put(chunk->skb, len); |
| 1178 | |
| 1179 | /* Copy data (whole iovec) into chunk */ |
| 1180 | if ((err = memcpy_fromiovecend(target, data, off, len))) |
| 1181 | goto out; |
| 1182 | |
| 1183 | /* Adjust the chunk length field. */ |
| 1184 | chunk->chunk_hdr->length = |
| 1185 | htons(ntohs(chunk->chunk_hdr->length) + len); |
| 1186 | chunk->chunk_end = chunk->skb->tail; |
| 1187 | |
| 1188 | out: |
| 1189 | return err; |
| 1190 | } |
| 1191 | |
| 1192 | /* Helper function to assign a TSN if needed. This assumes that both |
| 1193 | * the data_hdr and association have already been assigned. |
| 1194 | */ |
| 1195 | void sctp_chunk_assign_ssn(struct sctp_chunk *chunk) |
| 1196 | { |
| 1197 | __u16 ssn; |
| 1198 | __u16 sid; |
| 1199 | |
| 1200 | if (chunk->has_ssn) |
| 1201 | return; |
| 1202 | |
| 1203 | /* This is the last possible instant to assign a SSN. */ |
| 1204 | if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED) { |
| 1205 | ssn = 0; |
| 1206 | } else { |
| 1207 | sid = htons(chunk->subh.data_hdr->stream); |
| 1208 | if (chunk->chunk_hdr->flags & SCTP_DATA_LAST_FRAG) |
| 1209 | ssn = sctp_ssn_next(&chunk->asoc->ssnmap->out, sid); |
| 1210 | else |
| 1211 | ssn = sctp_ssn_peek(&chunk->asoc->ssnmap->out, sid); |
| 1212 | ssn = htons(ssn); |
| 1213 | } |
| 1214 | |
| 1215 | chunk->subh.data_hdr->ssn = ssn; |
| 1216 | chunk->has_ssn = 1; |
| 1217 | } |
| 1218 | |
| 1219 | /* Helper function to assign a TSN if needed. This assumes that both |
| 1220 | * the data_hdr and association have already been assigned. |
| 1221 | */ |
| 1222 | void sctp_chunk_assign_tsn(struct sctp_chunk *chunk) |
| 1223 | { |
| 1224 | if (!chunk->has_tsn) { |
| 1225 | /* This is the last possible instant to |
| 1226 | * assign a TSN. |
| 1227 | */ |
| 1228 | chunk->subh.data_hdr->tsn = |
| 1229 | htonl(sctp_association_get_next_tsn(chunk->asoc)); |
| 1230 | chunk->has_tsn = 1; |
| 1231 | } |
| 1232 | } |
| 1233 | |
| 1234 | /* Create a CLOSED association to use with an incoming packet. */ |
| 1235 | struct sctp_association *sctp_make_temp_asoc(const struct sctp_endpoint *ep, |
| 1236 | struct sctp_chunk *chunk, int gfp) |
| 1237 | { |
| 1238 | struct sctp_association *asoc; |
| 1239 | struct sk_buff *skb; |
| 1240 | sctp_scope_t scope; |
| 1241 | struct sctp_af *af; |
| 1242 | |
| 1243 | /* Create the bare association. */ |
| 1244 | scope = sctp_scope(sctp_source(chunk)); |
| 1245 | asoc = sctp_association_new(ep, ep->base.sk, scope, gfp); |
| 1246 | if (!asoc) |
| 1247 | goto nodata; |
| 1248 | asoc->temp = 1; |
| 1249 | skb = chunk->skb; |
| 1250 | /* Create an entry for the source address of the packet. */ |
| 1251 | af = sctp_get_af_specific(ipver2af(skb->nh.iph->version)); |
| 1252 | if (unlikely(!af)) |
| 1253 | goto fail; |
| 1254 | af->from_skb(&asoc->c.peer_addr, skb, 1); |
| 1255 | nodata: |
| 1256 | return asoc; |
| 1257 | |
| 1258 | fail: |
| 1259 | sctp_association_free(asoc); |
| 1260 | return NULL; |
| 1261 | } |
| 1262 | |
| 1263 | /* Build a cookie representing asoc. |
| 1264 | * This INCLUDES the param header needed to put the cookie in the INIT ACK. |
| 1265 | */ |
| 1266 | static sctp_cookie_param_t *sctp_pack_cookie(const struct sctp_endpoint *ep, |
| 1267 | const struct sctp_association *asoc, |
| 1268 | const struct sctp_chunk *init_chunk, |
| 1269 | int *cookie_len, |
| 1270 | const __u8 *raw_addrs, int addrs_len) |
| 1271 | { |
| 1272 | sctp_cookie_param_t *retval; |
| 1273 | struct sctp_signed_cookie *cookie; |
| 1274 | struct scatterlist sg; |
| 1275 | int headersize, bodysize; |
| 1276 | unsigned int keylen; |
| 1277 | char *key; |
| 1278 | |
| 1279 | headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE; |
| 1280 | bodysize = sizeof(struct sctp_cookie) |
| 1281 | + ntohs(init_chunk->chunk_hdr->length) + addrs_len; |
| 1282 | |
| 1283 | /* Pad out the cookie to a multiple to make the signature |
| 1284 | * functions simpler to write. |
| 1285 | */ |
| 1286 | if (bodysize % SCTP_COOKIE_MULTIPLE) |
| 1287 | bodysize += SCTP_COOKIE_MULTIPLE |
| 1288 | - (bodysize % SCTP_COOKIE_MULTIPLE); |
| 1289 | *cookie_len = headersize + bodysize; |
| 1290 | |
| 1291 | retval = (sctp_cookie_param_t *)kmalloc(*cookie_len, GFP_ATOMIC); |
| 1292 | |
| 1293 | if (!retval) { |
| 1294 | *cookie_len = 0; |
| 1295 | goto nodata; |
| 1296 | } |
| 1297 | |
| 1298 | /* Clear this memory since we are sending this data structure |
| 1299 | * out on the network. |
| 1300 | */ |
| 1301 | memset(retval, 0x00, *cookie_len); |
| 1302 | cookie = (struct sctp_signed_cookie *) retval->body; |
| 1303 | |
| 1304 | /* Set up the parameter header. */ |
| 1305 | retval->p.type = SCTP_PARAM_STATE_COOKIE; |
| 1306 | retval->p.length = htons(*cookie_len); |
| 1307 | |
| 1308 | /* Copy the cookie part of the association itself. */ |
| 1309 | cookie->c = asoc->c; |
| 1310 | /* Save the raw address list length in the cookie. */ |
| 1311 | cookie->c.raw_addr_list_len = addrs_len; |
| 1312 | |
| 1313 | /* Remember PR-SCTP capability. */ |
| 1314 | cookie->c.prsctp_capable = asoc->peer.prsctp_capable; |
| 1315 | |
| 1316 | /* Save adaption indication in the cookie. */ |
| 1317 | cookie->c.adaption_ind = asoc->peer.adaption_ind; |
| 1318 | |
| 1319 | /* Set an expiration time for the cookie. */ |
| 1320 | do_gettimeofday(&cookie->c.expiration); |
| 1321 | TIMEVAL_ADD(asoc->cookie_life, cookie->c.expiration); |
| 1322 | |
| 1323 | /* Copy the peer's init packet. */ |
| 1324 | memcpy(&cookie->c.peer_init[0], init_chunk->chunk_hdr, |
| 1325 | ntohs(init_chunk->chunk_hdr->length)); |
| 1326 | |
| 1327 | /* Copy the raw local address list of the association. */ |
| 1328 | memcpy((__u8 *)&cookie->c.peer_init[0] + |
| 1329 | ntohs(init_chunk->chunk_hdr->length), raw_addrs, addrs_len); |
| 1330 | |
| 1331 | if (sctp_sk(ep->base.sk)->hmac) { |
| 1332 | /* Sign the message. */ |
| 1333 | sg.page = virt_to_page(&cookie->c); |
| 1334 | sg.offset = (unsigned long)(&cookie->c) % PAGE_SIZE; |
| 1335 | sg.length = bodysize; |
| 1336 | keylen = SCTP_SECRET_SIZE; |
| 1337 | key = (char *)ep->secret_key[ep->current_key]; |
| 1338 | |
| 1339 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, |
| 1340 | &sg, 1, cookie->signature); |
| 1341 | } |
| 1342 | |
| 1343 | nodata: |
| 1344 | return retval; |
| 1345 | } |
| 1346 | |
| 1347 | /* Unpack the cookie from COOKIE ECHO chunk, recreating the association. */ |
| 1348 | struct sctp_association *sctp_unpack_cookie( |
| 1349 | const struct sctp_endpoint *ep, |
| 1350 | const struct sctp_association *asoc, |
| 1351 | struct sctp_chunk *chunk, int gfp, |
| 1352 | int *error, struct sctp_chunk **errp) |
| 1353 | { |
| 1354 | struct sctp_association *retval = NULL; |
| 1355 | struct sctp_signed_cookie *cookie; |
| 1356 | struct sctp_cookie *bear_cookie; |
| 1357 | int headersize, bodysize, fixed_size; |
| 1358 | __u8 digest[SCTP_SIGNATURE_SIZE]; |
| 1359 | struct scatterlist sg; |
| 1360 | unsigned int keylen, len; |
| 1361 | char *key; |
| 1362 | sctp_scope_t scope; |
| 1363 | struct sk_buff *skb = chunk->skb; |
| 1364 | |
| 1365 | headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE; |
| 1366 | bodysize = ntohs(chunk->chunk_hdr->length) - headersize; |
| 1367 | fixed_size = headersize + sizeof(struct sctp_cookie); |
| 1368 | |
| 1369 | /* Verify that the chunk looks like it even has a cookie. |
| 1370 | * There must be enough room for our cookie and our peer's |
| 1371 | * INIT chunk. |
| 1372 | */ |
| 1373 | len = ntohs(chunk->chunk_hdr->length); |
| 1374 | if (len < fixed_size + sizeof(struct sctp_chunkhdr)) |
| 1375 | goto malformed; |
| 1376 | |
| 1377 | /* Verify that the cookie has been padded out. */ |
| 1378 | if (bodysize % SCTP_COOKIE_MULTIPLE) |
| 1379 | goto malformed; |
| 1380 | |
| 1381 | /* Process the cookie. */ |
| 1382 | cookie = chunk->subh.cookie_hdr; |
| 1383 | bear_cookie = &cookie->c; |
| 1384 | |
| 1385 | if (!sctp_sk(ep->base.sk)->hmac) |
| 1386 | goto no_hmac; |
| 1387 | |
| 1388 | /* Check the signature. */ |
| 1389 | keylen = SCTP_SECRET_SIZE; |
| 1390 | sg.page = virt_to_page(bear_cookie); |
| 1391 | sg.offset = (unsigned long)(bear_cookie) % PAGE_SIZE; |
| 1392 | sg.length = bodysize; |
| 1393 | key = (char *)ep->secret_key[ep->current_key]; |
| 1394 | |
| 1395 | memset(digest, 0x00, sizeof(digest)); |
| 1396 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, &sg, |
| 1397 | 1, digest); |
| 1398 | |
| 1399 | if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) { |
| 1400 | /* Try the previous key. */ |
| 1401 | key = (char *)ep->secret_key[ep->last_key]; |
| 1402 | memset(digest, 0x00, sizeof(digest)); |
| 1403 | sctp_crypto_hmac(sctp_sk(ep->base.sk)->hmac, key, &keylen, |
| 1404 | &sg, 1, digest); |
| 1405 | |
| 1406 | if (memcmp(digest, cookie->signature, SCTP_SIGNATURE_SIZE)) { |
| 1407 | /* Yikes! Still bad signature! */ |
| 1408 | *error = -SCTP_IERROR_BAD_SIG; |
| 1409 | goto fail; |
| 1410 | } |
| 1411 | } |
| 1412 | |
| 1413 | no_hmac: |
| 1414 | /* IG Section 2.35.2: |
| 1415 | * 3) Compare the port numbers and the verification tag contained |
| 1416 | * within the COOKIE ECHO chunk to the actual port numbers and the |
| 1417 | * verification tag within the SCTP common header of the received |
| 1418 | * packet. If these values do not match the packet MUST be silently |
| 1419 | * discarded, |
| 1420 | */ |
| 1421 | if (ntohl(chunk->sctp_hdr->vtag) != bear_cookie->my_vtag) { |
| 1422 | *error = -SCTP_IERROR_BAD_TAG; |
| 1423 | goto fail; |
| 1424 | } |
| 1425 | |
| 1426 | if (ntohs(chunk->sctp_hdr->source) != bear_cookie->peer_addr.v4.sin_port || |
| 1427 | ntohs(chunk->sctp_hdr->dest) != bear_cookie->my_port) { |
| 1428 | *error = -SCTP_IERROR_BAD_PORTS; |
| 1429 | goto fail; |
| 1430 | } |
| 1431 | |
| 1432 | /* Check to see if the cookie is stale. If there is already |
| 1433 | * an association, there is no need to check cookie's expiration |
| 1434 | * for init collision case of lost COOKIE ACK. |
| 1435 | */ |
| 1436 | if (!asoc && tv_lt(bear_cookie->expiration, skb->stamp)) { |
| 1437 | __u16 len; |
| 1438 | /* |
| 1439 | * Section 3.3.10.3 Stale Cookie Error (3) |
| 1440 | * |
| 1441 | * Cause of error |
| 1442 | * --------------- |
| 1443 | * Stale Cookie Error: Indicates the receipt of a valid State |
| 1444 | * Cookie that has expired. |
| 1445 | */ |
| 1446 | len = ntohs(chunk->chunk_hdr->length); |
| 1447 | *errp = sctp_make_op_error_space(asoc, chunk, len); |
| 1448 | if (*errp) { |
| 1449 | suseconds_t usecs = (skb->stamp.tv_sec - |
| 1450 | bear_cookie->expiration.tv_sec) * 1000000L + |
| 1451 | skb->stamp.tv_usec - |
| 1452 | bear_cookie->expiration.tv_usec; |
| 1453 | |
| 1454 | usecs = htonl(usecs); |
| 1455 | sctp_init_cause(*errp, SCTP_ERROR_STALE_COOKIE, |
| 1456 | &usecs, sizeof(usecs)); |
| 1457 | *error = -SCTP_IERROR_STALE_COOKIE; |
| 1458 | } else |
| 1459 | *error = -SCTP_IERROR_NOMEM; |
| 1460 | |
| 1461 | goto fail; |
| 1462 | } |
| 1463 | |
| 1464 | /* Make a new base association. */ |
| 1465 | scope = sctp_scope(sctp_source(chunk)); |
| 1466 | retval = sctp_association_new(ep, ep->base.sk, scope, gfp); |
| 1467 | if (!retval) { |
| 1468 | *error = -SCTP_IERROR_NOMEM; |
| 1469 | goto fail; |
| 1470 | } |
| 1471 | |
| 1472 | /* Set up our peer's port number. */ |
| 1473 | retval->peer.port = ntohs(chunk->sctp_hdr->source); |
| 1474 | |
| 1475 | /* Populate the association from the cookie. */ |
| 1476 | memcpy(&retval->c, bear_cookie, sizeof(*bear_cookie)); |
| 1477 | |
| 1478 | if (sctp_assoc_set_bind_addr_from_cookie(retval, bear_cookie, |
| 1479 | GFP_ATOMIC) < 0) { |
| 1480 | *error = -SCTP_IERROR_NOMEM; |
| 1481 | goto fail; |
| 1482 | } |
| 1483 | |
| 1484 | /* Also, add the destination address. */ |
| 1485 | if (list_empty(&retval->base.bind_addr.address_list)) { |
| 1486 | sctp_add_bind_addr(&retval->base.bind_addr, &chunk->dest, |
| 1487 | GFP_ATOMIC); |
| 1488 | } |
| 1489 | |
| 1490 | retval->next_tsn = retval->c.initial_tsn; |
| 1491 | retval->ctsn_ack_point = retval->next_tsn - 1; |
| 1492 | retval->addip_serial = retval->c.initial_tsn; |
| 1493 | retval->adv_peer_ack_point = retval->ctsn_ack_point; |
| 1494 | retval->peer.prsctp_capable = retval->c.prsctp_capable; |
| 1495 | retval->peer.adaption_ind = retval->c.adaption_ind; |
| 1496 | |
| 1497 | /* The INIT stuff will be done by the side effects. */ |
| 1498 | return retval; |
| 1499 | |
| 1500 | fail: |
| 1501 | if (retval) |
| 1502 | sctp_association_free(retval); |
| 1503 | |
| 1504 | return NULL; |
| 1505 | |
| 1506 | malformed: |
| 1507 | /* Yikes! The packet is either corrupt or deliberately |
| 1508 | * malformed. |
| 1509 | */ |
| 1510 | *error = -SCTP_IERROR_MALFORMED; |
| 1511 | goto fail; |
| 1512 | } |
| 1513 | |
| 1514 | /******************************************************************** |
| 1515 | * 3rd Level Abstractions |
| 1516 | ********************************************************************/ |
| 1517 | |
| 1518 | struct __sctp_missing { |
| 1519 | __u32 num_missing; |
| 1520 | __u16 type; |
| 1521 | } __attribute__((packed)); |
| 1522 | |
| 1523 | /* |
| 1524 | * Report a missing mandatory parameter. |
| 1525 | */ |
| 1526 | static int sctp_process_missing_param(const struct sctp_association *asoc, |
| 1527 | sctp_param_t paramtype, |
| 1528 | struct sctp_chunk *chunk, |
| 1529 | struct sctp_chunk **errp) |
| 1530 | { |
| 1531 | struct __sctp_missing report; |
| 1532 | __u16 len; |
| 1533 | |
| 1534 | len = WORD_ROUND(sizeof(report)); |
| 1535 | |
| 1536 | /* Make an ERROR chunk, preparing enough room for |
| 1537 | * returning multiple unknown parameters. |
| 1538 | */ |
| 1539 | if (!*errp) |
| 1540 | *errp = sctp_make_op_error_space(asoc, chunk, len); |
| 1541 | |
| 1542 | if (*errp) { |
| 1543 | report.num_missing = htonl(1); |
| 1544 | report.type = paramtype; |
| 1545 | sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, |
| 1546 | &report, sizeof(report)); |
| 1547 | } |
| 1548 | |
| 1549 | /* Stop processing this chunk. */ |
| 1550 | return 0; |
| 1551 | } |
| 1552 | |
| 1553 | /* Report an Invalid Mandatory Parameter. */ |
| 1554 | static int sctp_process_inv_mandatory(const struct sctp_association *asoc, |
| 1555 | struct sctp_chunk *chunk, |
| 1556 | struct sctp_chunk **errp) |
| 1557 | { |
| 1558 | /* Invalid Mandatory Parameter Error has no payload. */ |
| 1559 | |
| 1560 | if (!*errp) |
| 1561 | *errp = sctp_make_op_error_space(asoc, chunk, 0); |
| 1562 | |
| 1563 | if (*errp) |
| 1564 | sctp_init_cause(*errp, SCTP_ERROR_INV_PARAM, NULL, 0); |
| 1565 | |
| 1566 | /* Stop processing this chunk. */ |
| 1567 | return 0; |
| 1568 | } |
| 1569 | |
| 1570 | static int sctp_process_inv_paramlength(const struct sctp_association *asoc, |
| 1571 | struct sctp_paramhdr *param, |
| 1572 | const struct sctp_chunk *chunk, |
| 1573 | struct sctp_chunk **errp) |
| 1574 | { |
| 1575 | char error[] = "The following parameter had invalid length:"; |
| 1576 | size_t payload_len = WORD_ROUND(sizeof(error)) + |
| 1577 | sizeof(sctp_paramhdr_t); |
| 1578 | |
| 1579 | |
| 1580 | /* Create an error chunk and fill it in with our payload. */ |
| 1581 | if (!*errp) |
| 1582 | *errp = sctp_make_op_error_space(asoc, chunk, payload_len); |
| 1583 | |
| 1584 | if (*errp) { |
| 1585 | sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, error, |
| 1586 | sizeof(error)); |
| 1587 | sctp_addto_chunk(*errp, sizeof(sctp_paramhdr_t), param); |
| 1588 | } |
| 1589 | |
| 1590 | return 0; |
| 1591 | } |
| 1592 | |
| 1593 | |
| 1594 | /* Do not attempt to handle the HOST_NAME parm. However, do |
| 1595 | * send back an indicator to the peer. |
| 1596 | */ |
| 1597 | static int sctp_process_hn_param(const struct sctp_association *asoc, |
| 1598 | union sctp_params param, |
| 1599 | struct sctp_chunk *chunk, |
| 1600 | struct sctp_chunk **errp) |
| 1601 | { |
| 1602 | __u16 len = ntohs(param.p->length); |
| 1603 | |
| 1604 | /* Make an ERROR chunk. */ |
| 1605 | if (!*errp) |
| 1606 | *errp = sctp_make_op_error_space(asoc, chunk, len); |
| 1607 | |
| 1608 | if (*errp) |
| 1609 | sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, |
| 1610 | param.v, len); |
| 1611 | |
| 1612 | /* Stop processing this chunk. */ |
| 1613 | return 0; |
| 1614 | } |
| 1615 | |
| 1616 | /* RFC 3.2.1 & the Implementers Guide 2.2. |
| 1617 | * |
| 1618 | * The Parameter Types are encoded such that the |
| 1619 | * highest-order two bits specify the action that must be |
| 1620 | * taken if the processing endpoint does not recognize the |
| 1621 | * Parameter Type. |
| 1622 | * |
| 1623 | * 00 - Stop processing this SCTP chunk and discard it, |
| 1624 | * do not process any further chunks within it. |
| 1625 | * |
| 1626 | * 01 - Stop processing this SCTP chunk and discard it, |
| 1627 | * do not process any further chunks within it, and report |
| 1628 | * the unrecognized parameter in an 'Unrecognized |
| 1629 | * Parameter Type' (in either an ERROR or in the INIT ACK). |
| 1630 | * |
| 1631 | * 10 - Skip this parameter and continue processing. |
| 1632 | * |
| 1633 | * 11 - Skip this parameter and continue processing but |
| 1634 | * report the unrecognized parameter in an |
| 1635 | * 'Unrecognized Parameter Type' (in either an ERROR or in |
| 1636 | * the INIT ACK). |
| 1637 | * |
| 1638 | * Return value: |
| 1639 | * 0 - discard the chunk |
| 1640 | * 1 - continue with the chunk |
| 1641 | */ |
| 1642 | static int sctp_process_unk_param(const struct sctp_association *asoc, |
| 1643 | union sctp_params param, |
| 1644 | struct sctp_chunk *chunk, |
| 1645 | struct sctp_chunk **errp) |
| 1646 | { |
| 1647 | int retval = 1; |
| 1648 | |
| 1649 | switch (param.p->type & SCTP_PARAM_ACTION_MASK) { |
| 1650 | case SCTP_PARAM_ACTION_DISCARD: |
| 1651 | retval = 0; |
| 1652 | break; |
| 1653 | case SCTP_PARAM_ACTION_DISCARD_ERR: |
| 1654 | retval = 0; |
| 1655 | /* Make an ERROR chunk, preparing enough room for |
| 1656 | * returning multiple unknown parameters. |
| 1657 | */ |
| 1658 | if (NULL == *errp) |
| 1659 | *errp = sctp_make_op_error_space(asoc, chunk, |
| 1660 | ntohs(chunk->chunk_hdr->length)); |
| 1661 | |
| 1662 | if (*errp) |
| 1663 | sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM, |
| 1664 | param.v, |
| 1665 | WORD_ROUND(ntohs(param.p->length))); |
| 1666 | |
| 1667 | break; |
| 1668 | case SCTP_PARAM_ACTION_SKIP: |
| 1669 | break; |
| 1670 | case SCTP_PARAM_ACTION_SKIP_ERR: |
| 1671 | /* Make an ERROR chunk, preparing enough room for |
| 1672 | * returning multiple unknown parameters. |
| 1673 | */ |
| 1674 | if (NULL == *errp) |
| 1675 | *errp = sctp_make_op_error_space(asoc, chunk, |
| 1676 | ntohs(chunk->chunk_hdr->length)); |
| 1677 | |
| 1678 | if (*errp) { |
| 1679 | sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM, |
| 1680 | param.v, |
| 1681 | WORD_ROUND(ntohs(param.p->length))); |
| 1682 | } else { |
| 1683 | /* If there is no memory for generating the ERROR |
| 1684 | * report as specified, an ABORT will be triggered |
| 1685 | * to the peer and the association won't be |
| 1686 | * established. |
| 1687 | */ |
| 1688 | retval = 0; |
| 1689 | } |
| 1690 | |
| 1691 | break; |
| 1692 | default: |
| 1693 | break; |
| 1694 | } |
| 1695 | |
| 1696 | return retval; |
| 1697 | } |
| 1698 | |
| 1699 | /* Find unrecognized parameters in the chunk. |
| 1700 | * Return values: |
| 1701 | * 0 - discard the chunk |
| 1702 | * 1 - continue with the chunk |
| 1703 | */ |
| 1704 | static int sctp_verify_param(const struct sctp_association *asoc, |
| 1705 | union sctp_params param, |
| 1706 | sctp_cid_t cid, |
| 1707 | struct sctp_chunk *chunk, |
| 1708 | struct sctp_chunk **err_chunk) |
| 1709 | { |
| 1710 | int retval = 1; |
| 1711 | |
| 1712 | /* FIXME - This routine is not looking at each parameter per the |
| 1713 | * chunk type, i.e., unrecognized parameters should be further |
| 1714 | * identified based on the chunk id. |
| 1715 | */ |
| 1716 | |
| 1717 | switch (param.p->type) { |
| 1718 | case SCTP_PARAM_IPV4_ADDRESS: |
| 1719 | case SCTP_PARAM_IPV6_ADDRESS: |
| 1720 | case SCTP_PARAM_COOKIE_PRESERVATIVE: |
| 1721 | case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES: |
| 1722 | case SCTP_PARAM_STATE_COOKIE: |
| 1723 | case SCTP_PARAM_HEARTBEAT_INFO: |
| 1724 | case SCTP_PARAM_UNRECOGNIZED_PARAMETERS: |
| 1725 | case SCTP_PARAM_ECN_CAPABLE: |
| 1726 | case SCTP_PARAM_ADAPTION_LAYER_IND: |
| 1727 | break; |
| 1728 | |
| 1729 | case SCTP_PARAM_HOST_NAME_ADDRESS: |
| 1730 | /* Tell the peer, we won't support this param. */ |
| 1731 | return sctp_process_hn_param(asoc, param, chunk, err_chunk); |
| 1732 | case SCTP_PARAM_FWD_TSN_SUPPORT: |
| 1733 | if (sctp_prsctp_enable) |
| 1734 | break; |
| 1735 | /* Fall Through */ |
| 1736 | default: |
| 1737 | SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n", |
| 1738 | ntohs(param.p->type), cid); |
| 1739 | return sctp_process_unk_param(asoc, param, chunk, err_chunk); |
| 1740 | |
| 1741 | break; |
| 1742 | } |
| 1743 | return retval; |
| 1744 | } |
| 1745 | |
| 1746 | /* Verify the INIT packet before we process it. */ |
| 1747 | int sctp_verify_init(const struct sctp_association *asoc, |
| 1748 | sctp_cid_t cid, |
| 1749 | sctp_init_chunk_t *peer_init, |
| 1750 | struct sctp_chunk *chunk, |
| 1751 | struct sctp_chunk **errp) |
| 1752 | { |
| 1753 | union sctp_params param; |
| 1754 | int has_cookie = 0; |
| 1755 | |
| 1756 | /* Verify stream values are non-zero. */ |
| 1757 | if ((0 == peer_init->init_hdr.num_outbound_streams) || |
| 1758 | (0 == peer_init->init_hdr.num_inbound_streams)) { |
| 1759 | |
| 1760 | sctp_process_inv_mandatory(asoc, chunk, errp); |
| 1761 | return 0; |
| 1762 | } |
| 1763 | |
| 1764 | /* Check for missing mandatory parameters. */ |
| 1765 | sctp_walk_params(param, peer_init, init_hdr.params) { |
| 1766 | |
| 1767 | if (SCTP_PARAM_STATE_COOKIE == param.p->type) |
| 1768 | has_cookie = 1; |
| 1769 | |
| 1770 | } /* for (loop through all parameters) */ |
| 1771 | |
| 1772 | /* There is a possibility that a parameter length was bad and |
| 1773 | * in that case we would have stoped walking the parameters. |
| 1774 | * The current param.p would point at the bad one. |
| 1775 | * Current consensus on the mailing list is to generate a PROTOCOL |
| 1776 | * VIOLATION error. We build the ERROR chunk here and let the normal |
| 1777 | * error handling code build and send the packet. |
| 1778 | */ |
| 1779 | if (param.v < (void*)chunk->chunk_end - sizeof(sctp_paramhdr_t)) { |
| 1780 | sctp_process_inv_paramlength(asoc, param.p, chunk, errp); |
| 1781 | return 0; |
| 1782 | } |
| 1783 | |
| 1784 | /* The only missing mandatory param possible today is |
| 1785 | * the state cookie for an INIT-ACK chunk. |
| 1786 | */ |
| 1787 | if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) { |
| 1788 | sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE, |
| 1789 | chunk, errp); |
| 1790 | return 0; |
| 1791 | } |
| 1792 | |
| 1793 | /* Find unrecognized parameters. */ |
| 1794 | |
| 1795 | sctp_walk_params(param, peer_init, init_hdr.params) { |
| 1796 | |
| 1797 | if (!sctp_verify_param(asoc, param, cid, chunk, errp)) { |
| 1798 | if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type) |
| 1799 | return 0; |
| 1800 | else |
| 1801 | return 1; |
| 1802 | } |
| 1803 | |
| 1804 | } /* for (loop through all parameters) */ |
| 1805 | |
| 1806 | return 1; |
| 1807 | } |
| 1808 | |
| 1809 | /* Unpack the parameters in an INIT packet into an association. |
| 1810 | * Returns 0 on failure, else success. |
| 1811 | * FIXME: This is an association method. |
| 1812 | */ |
| 1813 | int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid, |
| 1814 | const union sctp_addr *peer_addr, |
| 1815 | sctp_init_chunk_t *peer_init, int gfp) |
| 1816 | { |
| 1817 | union sctp_params param; |
| 1818 | struct sctp_transport *transport; |
| 1819 | struct list_head *pos, *temp; |
| 1820 | char *cookie; |
| 1821 | |
| 1822 | /* We must include the address that the INIT packet came from. |
| 1823 | * This is the only address that matters for an INIT packet. |
| 1824 | * When processing a COOKIE ECHO, we retrieve the from address |
| 1825 | * of the INIT from the cookie. |
| 1826 | */ |
| 1827 | |
| 1828 | /* This implementation defaults to making the first transport |
| 1829 | * added as the primary transport. The source address seems to |
| 1830 | * be a a better choice than any of the embedded addresses. |
| 1831 | */ |
| 1832 | if (peer_addr) |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 1833 | if(!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1834 | goto nomem; |
| 1835 | |
| 1836 | /* Process the initialization parameters. */ |
| 1837 | |
| 1838 | sctp_walk_params(param, peer_init, init_hdr.params) { |
| 1839 | |
| 1840 | if (!sctp_process_param(asoc, param, peer_addr, gfp)) |
| 1841 | goto clean_up; |
| 1842 | } |
| 1843 | |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 1844 | /* Walk list of transports, removing transports in the UNKNOWN state. */ |
| 1845 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { |
| 1846 | transport = list_entry(pos, struct sctp_transport, transports); |
| 1847 | if (transport->state == SCTP_UNKNOWN) { |
| 1848 | sctp_assoc_rm_peer(asoc, transport); |
| 1849 | } |
| 1850 | } |
| 1851 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1852 | /* The fixed INIT headers are always in network byte |
| 1853 | * order. |
| 1854 | */ |
| 1855 | asoc->peer.i.init_tag = |
| 1856 | ntohl(peer_init->init_hdr.init_tag); |
| 1857 | asoc->peer.i.a_rwnd = |
| 1858 | ntohl(peer_init->init_hdr.a_rwnd); |
| 1859 | asoc->peer.i.num_outbound_streams = |
| 1860 | ntohs(peer_init->init_hdr.num_outbound_streams); |
| 1861 | asoc->peer.i.num_inbound_streams = |
| 1862 | ntohs(peer_init->init_hdr.num_inbound_streams); |
| 1863 | asoc->peer.i.initial_tsn = |
| 1864 | ntohl(peer_init->init_hdr.initial_tsn); |
| 1865 | |
| 1866 | /* Apply the upper bounds for output streams based on peer's |
| 1867 | * number of inbound streams. |
| 1868 | */ |
| 1869 | if (asoc->c.sinit_num_ostreams > |
| 1870 | ntohs(peer_init->init_hdr.num_inbound_streams)) { |
| 1871 | asoc->c.sinit_num_ostreams = |
| 1872 | ntohs(peer_init->init_hdr.num_inbound_streams); |
| 1873 | } |
| 1874 | |
| 1875 | if (asoc->c.sinit_max_instreams > |
| 1876 | ntohs(peer_init->init_hdr.num_outbound_streams)) { |
| 1877 | asoc->c.sinit_max_instreams = |
| 1878 | ntohs(peer_init->init_hdr.num_outbound_streams); |
| 1879 | } |
| 1880 | |
| 1881 | /* Copy Initiation tag from INIT to VT_peer in cookie. */ |
| 1882 | asoc->c.peer_vtag = asoc->peer.i.init_tag; |
| 1883 | |
| 1884 | /* Peer Rwnd : Current calculated value of the peer's rwnd. */ |
| 1885 | asoc->peer.rwnd = asoc->peer.i.a_rwnd; |
| 1886 | |
| 1887 | /* Copy cookie in case we need to resend COOKIE-ECHO. */ |
| 1888 | cookie = asoc->peer.cookie; |
| 1889 | if (cookie) { |
| 1890 | asoc->peer.cookie = kmalloc(asoc->peer.cookie_len, gfp); |
| 1891 | if (!asoc->peer.cookie) |
| 1892 | goto clean_up; |
| 1893 | memcpy(asoc->peer.cookie, cookie, asoc->peer.cookie_len); |
| 1894 | } |
| 1895 | |
| 1896 | /* RFC 2960 7.2.1 The initial value of ssthresh MAY be arbitrarily |
| 1897 | * high (for example, implementations MAY use the size of the receiver |
| 1898 | * advertised window). |
| 1899 | */ |
| 1900 | list_for_each(pos, &asoc->peer.transport_addr_list) { |
| 1901 | transport = list_entry(pos, struct sctp_transport, transports); |
| 1902 | transport->ssthresh = asoc->peer.i.a_rwnd; |
| 1903 | } |
| 1904 | |
| 1905 | /* Set up the TSN tracking pieces. */ |
| 1906 | sctp_tsnmap_init(&asoc->peer.tsn_map, SCTP_TSN_MAP_SIZE, |
| 1907 | asoc->peer.i.initial_tsn); |
| 1908 | |
| 1909 | /* RFC 2960 6.5 Stream Identifier and Stream Sequence Number |
| 1910 | * |
| 1911 | * The stream sequence number in all the streams shall start |
| 1912 | * from 0 when the association is established. Also, when the |
| 1913 | * stream sequence number reaches the value 65535 the next |
| 1914 | * stream sequence number shall be set to 0. |
| 1915 | */ |
| 1916 | |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 1917 | /* Allocate storage for the negotiated streams if it is not a temporary |
| 1918 | * association. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1919 | */ |
| 1920 | if (!asoc->temp) { |
| 1921 | int assoc_id; |
| 1922 | int error; |
| 1923 | |
| 1924 | asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams, |
| 1925 | asoc->c.sinit_num_ostreams, gfp); |
| 1926 | if (!asoc->ssnmap) |
| 1927 | goto clean_up; |
| 1928 | |
| 1929 | retry: |
| 1930 | if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp))) |
| 1931 | goto clean_up; |
| 1932 | spin_lock_bh(&sctp_assocs_id_lock); |
| 1933 | error = idr_get_new_above(&sctp_assocs_id, (void *)asoc, 1, |
| 1934 | &assoc_id); |
| 1935 | spin_unlock_bh(&sctp_assocs_id_lock); |
| 1936 | if (error == -EAGAIN) |
| 1937 | goto retry; |
| 1938 | else if (error) |
| 1939 | goto clean_up; |
| 1940 | |
| 1941 | asoc->assoc_id = (sctp_assoc_t) assoc_id; |
| 1942 | } |
| 1943 | |
| 1944 | /* ADDIP Section 4.1 ASCONF Chunk Procedures |
| 1945 | * |
| 1946 | * When an endpoint has an ASCONF signaled change to be sent to the |
| 1947 | * remote endpoint it should do the following: |
| 1948 | * ... |
| 1949 | * A2) A serial number should be assigned to the Chunk. The serial |
| 1950 | * number should be a monotonically increasing number. All serial |
| 1951 | * numbers are defined to be initialized at the start of the |
| 1952 | * association to the same value as the Initial TSN. |
| 1953 | */ |
| 1954 | asoc->peer.addip_serial = asoc->peer.i.initial_tsn - 1; |
| 1955 | return 1; |
| 1956 | |
| 1957 | clean_up: |
| 1958 | /* Release the transport structures. */ |
| 1959 | list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) { |
| 1960 | transport = list_entry(pos, struct sctp_transport, transports); |
| 1961 | list_del_init(pos); |
| 1962 | sctp_transport_free(transport); |
| 1963 | } |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 1964 | |
| 1965 | asoc->peer.transport_count = 0; |
| 1966 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1967 | nomem: |
| 1968 | return 0; |
| 1969 | } |
| 1970 | |
| 1971 | |
| 1972 | /* Update asoc with the option described in param. |
| 1973 | * |
| 1974 | * RFC2960 3.3.2.1 Optional/Variable Length Parameters in INIT |
| 1975 | * |
| 1976 | * asoc is the association to update. |
| 1977 | * param is the variable length parameter to use for update. |
| 1978 | * cid tells us if this is an INIT, INIT ACK or COOKIE ECHO. |
| 1979 | * If the current packet is an INIT we want to minimize the amount of |
| 1980 | * work we do. In particular, we should not build transport |
| 1981 | * structures for the addresses. |
| 1982 | */ |
| 1983 | static int sctp_process_param(struct sctp_association *asoc, |
| 1984 | union sctp_params param, |
| 1985 | const union sctp_addr *peer_addr, |
| 1986 | int gfp) |
| 1987 | { |
| 1988 | union sctp_addr addr; |
| 1989 | int i; |
| 1990 | __u16 sat; |
| 1991 | int retval = 1; |
| 1992 | sctp_scope_t scope; |
| 1993 | time_t stale; |
| 1994 | struct sctp_af *af; |
| 1995 | |
| 1996 | /* We maintain all INIT parameters in network byte order all the |
| 1997 | * time. This allows us to not worry about whether the parameters |
| 1998 | * came from a fresh INIT, and INIT ACK, or were stored in a cookie. |
| 1999 | */ |
| 2000 | switch (param.p->type) { |
| 2001 | case SCTP_PARAM_IPV6_ADDRESS: |
| 2002 | if (PF_INET6 != asoc->base.sk->sk_family) |
| 2003 | break; |
| 2004 | /* Fall through. */ |
| 2005 | case SCTP_PARAM_IPV4_ADDRESS: |
| 2006 | af = sctp_get_af_specific(param_type2af(param.p->type)); |
| 2007 | af->from_addr_param(&addr, param.addr, asoc->peer.port, 0); |
| 2008 | scope = sctp_scope(peer_addr); |
| 2009 | if (sctp_in_scope(&addr, scope)) |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 2010 | if (!sctp_assoc_add_peer(asoc, &addr, gfp, SCTP_ACTIVE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2011 | return 0; |
| 2012 | break; |
| 2013 | |
| 2014 | case SCTP_PARAM_COOKIE_PRESERVATIVE: |
| 2015 | if (!sctp_cookie_preserve_enable) |
| 2016 | break; |
| 2017 | |
| 2018 | stale = ntohl(param.life->lifespan_increment); |
| 2019 | |
| 2020 | /* Suggested Cookie Life span increment's unit is msec, |
| 2021 | * (1/1000sec). |
| 2022 | */ |
| 2023 | asoc->cookie_life.tv_sec += stale / 1000; |
| 2024 | asoc->cookie_life.tv_usec += (stale % 1000) * 1000; |
| 2025 | break; |
| 2026 | |
| 2027 | case SCTP_PARAM_HOST_NAME_ADDRESS: |
| 2028 | SCTP_DEBUG_PRINTK("unimplemented SCTP_HOST_NAME_ADDRESS\n"); |
| 2029 | break; |
| 2030 | |
| 2031 | case SCTP_PARAM_SUPPORTED_ADDRESS_TYPES: |
| 2032 | /* Turn off the default values first so we'll know which |
| 2033 | * ones are really set by the peer. |
| 2034 | */ |
| 2035 | asoc->peer.ipv4_address = 0; |
| 2036 | asoc->peer.ipv6_address = 0; |
| 2037 | |
| 2038 | /* Cycle through address types; avoid divide by 0. */ |
| 2039 | sat = ntohs(param.p->length) - sizeof(sctp_paramhdr_t); |
| 2040 | if (sat) |
| 2041 | sat /= sizeof(__u16); |
| 2042 | |
| 2043 | for (i = 0; i < sat; ++i) { |
| 2044 | switch (param.sat->types[i]) { |
| 2045 | case SCTP_PARAM_IPV4_ADDRESS: |
| 2046 | asoc->peer.ipv4_address = 1; |
| 2047 | break; |
| 2048 | |
| 2049 | case SCTP_PARAM_IPV6_ADDRESS: |
| 2050 | asoc->peer.ipv6_address = 1; |
| 2051 | break; |
| 2052 | |
| 2053 | case SCTP_PARAM_HOST_NAME_ADDRESS: |
| 2054 | asoc->peer.hostname_address = 1; |
| 2055 | break; |
| 2056 | |
| 2057 | default: /* Just ignore anything else. */ |
| 2058 | break; |
| 2059 | }; |
| 2060 | } |
| 2061 | break; |
| 2062 | |
| 2063 | case SCTP_PARAM_STATE_COOKIE: |
| 2064 | asoc->peer.cookie_len = |
| 2065 | ntohs(param.p->length) - sizeof(sctp_paramhdr_t); |
| 2066 | asoc->peer.cookie = param.cookie->body; |
| 2067 | break; |
| 2068 | |
| 2069 | case SCTP_PARAM_HEARTBEAT_INFO: |
| 2070 | /* Would be odd to receive, but it causes no problems. */ |
| 2071 | break; |
| 2072 | |
| 2073 | case SCTP_PARAM_UNRECOGNIZED_PARAMETERS: |
| 2074 | /* Rejected during verify stage. */ |
| 2075 | break; |
| 2076 | |
| 2077 | case SCTP_PARAM_ECN_CAPABLE: |
| 2078 | asoc->peer.ecn_capable = 1; |
| 2079 | break; |
| 2080 | |
| 2081 | case SCTP_PARAM_ADAPTION_LAYER_IND: |
| 2082 | asoc->peer.adaption_ind = param.aind->adaption_ind; |
| 2083 | break; |
| 2084 | |
| 2085 | case SCTP_PARAM_FWD_TSN_SUPPORT: |
| 2086 | if (sctp_prsctp_enable) { |
| 2087 | asoc->peer.prsctp_capable = 1; |
| 2088 | break; |
| 2089 | } |
| 2090 | /* Fall Through */ |
| 2091 | default: |
| 2092 | /* Any unrecognized parameters should have been caught |
| 2093 | * and handled by sctp_verify_param() which should be |
| 2094 | * called prior to this routine. Simply log the error |
| 2095 | * here. |
| 2096 | */ |
| 2097 | SCTP_DEBUG_PRINTK("Ignoring param: %d for association %p.\n", |
| 2098 | ntohs(param.p->type), asoc); |
| 2099 | break; |
| 2100 | }; |
| 2101 | |
| 2102 | return retval; |
| 2103 | } |
| 2104 | |
| 2105 | /* Select a new verification tag. */ |
| 2106 | __u32 sctp_generate_tag(const struct sctp_endpoint *ep) |
| 2107 | { |
| 2108 | /* I believe that this random number generator complies with RFC1750. |
| 2109 | * A tag of 0 is reserved for special cases (e.g. INIT). |
| 2110 | */ |
| 2111 | __u32 x; |
| 2112 | |
| 2113 | do { |
| 2114 | get_random_bytes(&x, sizeof(__u32)); |
| 2115 | } while (x == 0); |
| 2116 | |
| 2117 | return x; |
| 2118 | } |
| 2119 | |
| 2120 | /* Select an initial TSN to send during startup. */ |
| 2121 | __u32 sctp_generate_tsn(const struct sctp_endpoint *ep) |
| 2122 | { |
| 2123 | __u32 retval; |
| 2124 | |
| 2125 | get_random_bytes(&retval, sizeof(__u32)); |
| 2126 | return retval; |
| 2127 | } |
| 2128 | |
| 2129 | /* |
| 2130 | * ADDIP 3.1.1 Address Configuration Change Chunk (ASCONF) |
| 2131 | * 0 1 2 3 |
| 2132 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 2133 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2134 | * | Type = 0xC1 | Chunk Flags | Chunk Length | |
| 2135 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2136 | * | Serial Number | |
| 2137 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2138 | * | Address Parameter | |
| 2139 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2140 | * | ASCONF Parameter #1 | |
| 2141 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2142 | * \ \ |
| 2143 | * / .... / |
| 2144 | * \ \ |
| 2145 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2146 | * | ASCONF Parameter #N | |
| 2147 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2148 | * |
| 2149 | * Address Parameter and other parameter will not be wrapped in this function |
| 2150 | */ |
| 2151 | static struct sctp_chunk *sctp_make_asconf(struct sctp_association *asoc, |
| 2152 | union sctp_addr *addr, |
| 2153 | int vparam_len) |
| 2154 | { |
| 2155 | sctp_addiphdr_t asconf; |
| 2156 | struct sctp_chunk *retval; |
| 2157 | int length = sizeof(asconf) + vparam_len; |
| 2158 | union sctp_addr_param addrparam; |
| 2159 | int addrlen; |
| 2160 | struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family); |
| 2161 | |
| 2162 | addrlen = af->to_addr_param(addr, &addrparam); |
| 2163 | if (!addrlen) |
| 2164 | return NULL; |
| 2165 | length += addrlen; |
| 2166 | |
| 2167 | /* Create the chunk. */ |
| 2168 | retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF, 0, length); |
| 2169 | if (!retval) |
| 2170 | return NULL; |
| 2171 | |
| 2172 | asconf.serial = htonl(asoc->addip_serial++); |
| 2173 | |
| 2174 | retval->subh.addip_hdr = |
| 2175 | sctp_addto_chunk(retval, sizeof(asconf), &asconf); |
| 2176 | retval->param_hdr.v = |
| 2177 | sctp_addto_chunk(retval, addrlen, &addrparam); |
| 2178 | |
| 2179 | return retval; |
| 2180 | } |
| 2181 | |
| 2182 | /* ADDIP |
| 2183 | * 3.2.1 Add IP Address |
| 2184 | * 0 1 2 3 |
| 2185 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 2186 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2187 | * | Type = 0xC001 | Length = Variable | |
| 2188 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2189 | * | ASCONF-Request Correlation ID | |
| 2190 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2191 | * | Address Parameter | |
| 2192 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2193 | * |
| 2194 | * 3.2.2 Delete IP Address |
| 2195 | * 0 1 2 3 |
| 2196 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 2197 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2198 | * | Type = 0xC002 | Length = Variable | |
| 2199 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2200 | * | ASCONF-Request Correlation ID | |
| 2201 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2202 | * | Address Parameter | |
| 2203 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2204 | * |
| 2205 | */ |
| 2206 | struct sctp_chunk *sctp_make_asconf_update_ip(struct sctp_association *asoc, |
| 2207 | union sctp_addr *laddr, |
| 2208 | struct sockaddr *addrs, |
| 2209 | int addrcnt, |
| 2210 | __u16 flags) |
| 2211 | { |
| 2212 | sctp_addip_param_t param; |
| 2213 | struct sctp_chunk *retval; |
| 2214 | union sctp_addr_param addr_param; |
| 2215 | union sctp_addr *addr; |
| 2216 | void *addr_buf; |
| 2217 | struct sctp_af *af; |
| 2218 | int paramlen = sizeof(param); |
| 2219 | int addr_param_len = 0; |
| 2220 | int totallen = 0; |
| 2221 | int i; |
| 2222 | |
| 2223 | /* Get total length of all the address parameters. */ |
| 2224 | addr_buf = addrs; |
| 2225 | for (i = 0; i < addrcnt; i++) { |
| 2226 | addr = (union sctp_addr *)addr_buf; |
| 2227 | af = sctp_get_af_specific(addr->v4.sin_family); |
| 2228 | addr_param_len = af->to_addr_param(addr, &addr_param); |
| 2229 | |
| 2230 | totallen += paramlen; |
| 2231 | totallen += addr_param_len; |
| 2232 | |
| 2233 | addr_buf += af->sockaddr_len; |
| 2234 | } |
| 2235 | |
| 2236 | /* Create an asconf chunk with the required length. */ |
| 2237 | retval = sctp_make_asconf(asoc, laddr, totallen); |
| 2238 | if (!retval) |
| 2239 | return NULL; |
| 2240 | |
| 2241 | /* Add the address parameters to the asconf chunk. */ |
| 2242 | addr_buf = addrs; |
| 2243 | for (i = 0; i < addrcnt; i++) { |
| 2244 | addr = (union sctp_addr *)addr_buf; |
| 2245 | af = sctp_get_af_specific(addr->v4.sin_family); |
| 2246 | addr_param_len = af->to_addr_param(addr, &addr_param); |
| 2247 | param.param_hdr.type = flags; |
| 2248 | param.param_hdr.length = htons(paramlen + addr_param_len); |
| 2249 | param.crr_id = i; |
| 2250 | |
| 2251 | sctp_addto_chunk(retval, paramlen, ¶m); |
| 2252 | sctp_addto_chunk(retval, addr_param_len, &addr_param); |
| 2253 | |
| 2254 | addr_buf += af->sockaddr_len; |
| 2255 | } |
| 2256 | return retval; |
| 2257 | } |
| 2258 | |
| 2259 | /* ADDIP |
| 2260 | * 3.2.4 Set Primary IP Address |
| 2261 | * 0 1 2 3 |
| 2262 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 2263 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2264 | * | Type =0xC004 | Length = Variable | |
| 2265 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2266 | * | ASCONF-Request Correlation ID | |
| 2267 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2268 | * | Address Parameter | |
| 2269 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2270 | * |
| 2271 | * Create an ASCONF chunk with Set Primary IP address parameter. |
| 2272 | */ |
| 2273 | struct sctp_chunk *sctp_make_asconf_set_prim(struct sctp_association *asoc, |
| 2274 | union sctp_addr *addr) |
| 2275 | { |
| 2276 | sctp_addip_param_t param; |
| 2277 | struct sctp_chunk *retval; |
| 2278 | int len = sizeof(param); |
| 2279 | union sctp_addr_param addrparam; |
| 2280 | int addrlen; |
| 2281 | struct sctp_af *af = sctp_get_af_specific(addr->v4.sin_family); |
| 2282 | |
| 2283 | addrlen = af->to_addr_param(addr, &addrparam); |
| 2284 | if (!addrlen) |
| 2285 | return NULL; |
| 2286 | len += addrlen; |
| 2287 | |
| 2288 | /* Create the chunk and make asconf header. */ |
| 2289 | retval = sctp_make_asconf(asoc, addr, len); |
| 2290 | if (!retval) |
| 2291 | return NULL; |
| 2292 | |
| 2293 | param.param_hdr.type = SCTP_PARAM_SET_PRIMARY; |
| 2294 | param.param_hdr.length = htons(len); |
| 2295 | param.crr_id = 0; |
| 2296 | |
| 2297 | sctp_addto_chunk(retval, sizeof(param), ¶m); |
| 2298 | sctp_addto_chunk(retval, addrlen, &addrparam); |
| 2299 | |
| 2300 | return retval; |
| 2301 | } |
| 2302 | |
| 2303 | /* ADDIP 3.1.2 Address Configuration Acknowledgement Chunk (ASCONF-ACK) |
| 2304 | * 0 1 2 3 |
| 2305 | * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 |
| 2306 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2307 | * | Type = 0x80 | Chunk Flags | Chunk Length | |
| 2308 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2309 | * | Serial Number | |
| 2310 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2311 | * | ASCONF Parameter Response#1 | |
| 2312 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2313 | * \ \ |
| 2314 | * / .... / |
| 2315 | * \ \ |
| 2316 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2317 | * | ASCONF Parameter Response#N | |
| 2318 | * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| 2319 | * |
| 2320 | * Create an ASCONF_ACK chunk with enough space for the parameter responses. |
| 2321 | */ |
| 2322 | static struct sctp_chunk *sctp_make_asconf_ack(const struct sctp_association *asoc, |
| 2323 | __u32 serial, int vparam_len) |
| 2324 | { |
| 2325 | sctp_addiphdr_t asconf; |
| 2326 | struct sctp_chunk *retval; |
| 2327 | int length = sizeof(asconf) + vparam_len; |
| 2328 | |
| 2329 | /* Create the chunk. */ |
| 2330 | retval = sctp_make_chunk(asoc, SCTP_CID_ASCONF_ACK, 0, length); |
| 2331 | if (!retval) |
| 2332 | return NULL; |
| 2333 | |
| 2334 | asconf.serial = htonl(serial); |
| 2335 | |
| 2336 | retval->subh.addip_hdr = |
| 2337 | sctp_addto_chunk(retval, sizeof(asconf), &asconf); |
| 2338 | |
| 2339 | return retval; |
| 2340 | } |
| 2341 | |
| 2342 | /* Add response parameters to an ASCONF_ACK chunk. */ |
| 2343 | static void sctp_add_asconf_response(struct sctp_chunk *chunk, __u32 crr_id, |
| 2344 | __u16 err_code, sctp_addip_param_t *asconf_param) |
| 2345 | { |
| 2346 | sctp_addip_param_t ack_param; |
| 2347 | sctp_errhdr_t err_param; |
| 2348 | int asconf_param_len = 0; |
| 2349 | int err_param_len = 0; |
| 2350 | __u16 response_type; |
| 2351 | |
| 2352 | if (SCTP_ERROR_NO_ERROR == err_code) { |
| 2353 | response_type = SCTP_PARAM_SUCCESS_REPORT; |
| 2354 | } else { |
| 2355 | response_type = SCTP_PARAM_ERR_CAUSE; |
| 2356 | err_param_len = sizeof(err_param); |
| 2357 | if (asconf_param) |
| 2358 | asconf_param_len = |
| 2359 | ntohs(asconf_param->param_hdr.length); |
| 2360 | } |
| 2361 | |
| 2362 | /* Add Success Indication or Error Cause Indication parameter. */ |
| 2363 | ack_param.param_hdr.type = response_type; |
| 2364 | ack_param.param_hdr.length = htons(sizeof(ack_param) + |
| 2365 | err_param_len + |
| 2366 | asconf_param_len); |
| 2367 | ack_param.crr_id = crr_id; |
| 2368 | sctp_addto_chunk(chunk, sizeof(ack_param), &ack_param); |
| 2369 | |
| 2370 | if (SCTP_ERROR_NO_ERROR == err_code) |
| 2371 | return; |
| 2372 | |
| 2373 | /* Add Error Cause parameter. */ |
| 2374 | err_param.cause = err_code; |
| 2375 | err_param.length = htons(err_param_len + asconf_param_len); |
| 2376 | sctp_addto_chunk(chunk, err_param_len, &err_param); |
| 2377 | |
| 2378 | /* Add the failed TLV copied from ASCONF chunk. */ |
| 2379 | if (asconf_param) |
| 2380 | sctp_addto_chunk(chunk, asconf_param_len, asconf_param); |
| 2381 | } |
| 2382 | |
| 2383 | /* Process a asconf parameter. */ |
| 2384 | static __u16 sctp_process_asconf_param(struct sctp_association *asoc, |
| 2385 | struct sctp_chunk *asconf, |
| 2386 | sctp_addip_param_t *asconf_param) |
| 2387 | { |
| 2388 | struct sctp_transport *peer; |
| 2389 | struct sctp_af *af; |
| 2390 | union sctp_addr addr; |
| 2391 | struct list_head *pos; |
| 2392 | union sctp_addr_param *addr_param; |
| 2393 | |
| 2394 | addr_param = (union sctp_addr_param *) |
| 2395 | ((void *)asconf_param + sizeof(sctp_addip_param_t)); |
| 2396 | |
| 2397 | af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type)); |
| 2398 | if (unlikely(!af)) |
| 2399 | return SCTP_ERROR_INV_PARAM; |
| 2400 | |
| 2401 | af->from_addr_param(&addr, addr_param, asoc->peer.port, 0); |
| 2402 | switch (asconf_param->param_hdr.type) { |
| 2403 | case SCTP_PARAM_ADD_IP: |
| 2404 | /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address |
| 2405 | * request and does not have the local resources to add this |
| 2406 | * new address to the association, it MUST return an Error |
| 2407 | * Cause TLV set to the new error code 'Operation Refused |
| 2408 | * Due to Resource Shortage'. |
| 2409 | */ |
| 2410 | |
Frank Filz | 3f7a87d | 2005-06-20 13:14:57 -0700 | [diff] [blame] | 2411 | peer = sctp_assoc_add_peer(asoc, &addr, GFP_ATOMIC, SCTP_ACTIVE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2412 | if (!peer) |
| 2413 | return SCTP_ERROR_RSRC_LOW; |
| 2414 | |
| 2415 | /* Start the heartbeat timer. */ |
| 2416 | if (!mod_timer(&peer->hb_timer, sctp_transport_timeout(peer))) |
| 2417 | sctp_transport_hold(peer); |
| 2418 | break; |
| 2419 | case SCTP_PARAM_DEL_IP: |
| 2420 | /* ADDIP 4.3 D7) If a request is received to delete the |
| 2421 | * last remaining IP address of a peer endpoint, the receiver |
| 2422 | * MUST send an Error Cause TLV with the error cause set to the |
| 2423 | * new error code 'Request to Delete Last Remaining IP Address'. |
| 2424 | */ |
| 2425 | pos = asoc->peer.transport_addr_list.next; |
| 2426 | if (pos->next == &asoc->peer.transport_addr_list) |
| 2427 | return SCTP_ERROR_DEL_LAST_IP; |
| 2428 | |
| 2429 | /* ADDIP 4.3 D8) If a request is received to delete an IP |
| 2430 | * address which is also the source address of the IP packet |
| 2431 | * which contained the ASCONF chunk, the receiver MUST reject |
| 2432 | * this request. To reject the request the receiver MUST send |
| 2433 | * an Error Cause TLV set to the new error code 'Request to |
| 2434 | * Delete Source IP Address' |
| 2435 | */ |
| 2436 | if (sctp_cmp_addr_exact(sctp_source(asconf), &addr)) |
| 2437 | return SCTP_ERROR_DEL_SRC_IP; |
| 2438 | |
| 2439 | sctp_assoc_del_peer(asoc, &addr); |
| 2440 | break; |
| 2441 | case SCTP_PARAM_SET_PRIMARY: |
| 2442 | peer = sctp_assoc_lookup_paddr(asoc, &addr); |
| 2443 | if (!peer) |
| 2444 | return SCTP_ERROR_INV_PARAM; |
| 2445 | |
| 2446 | sctp_assoc_set_primary(asoc, peer); |
| 2447 | break; |
| 2448 | default: |
| 2449 | return SCTP_ERROR_INV_PARAM; |
| 2450 | break; |
| 2451 | } |
| 2452 | |
| 2453 | return SCTP_ERROR_NO_ERROR; |
| 2454 | } |
| 2455 | |
| 2456 | /* Process an incoming ASCONF chunk with the next expected serial no. and |
| 2457 | * return an ASCONF_ACK chunk to be sent in response. |
| 2458 | */ |
| 2459 | struct sctp_chunk *sctp_process_asconf(struct sctp_association *asoc, |
| 2460 | struct sctp_chunk *asconf) |
| 2461 | { |
| 2462 | sctp_addiphdr_t *hdr; |
| 2463 | union sctp_addr_param *addr_param; |
| 2464 | sctp_addip_param_t *asconf_param; |
| 2465 | struct sctp_chunk *asconf_ack; |
| 2466 | |
| 2467 | __u16 err_code; |
| 2468 | int length = 0; |
| 2469 | int chunk_len = asconf->skb->len; |
| 2470 | __u32 serial; |
| 2471 | int all_param_pass = 1; |
| 2472 | |
| 2473 | hdr = (sctp_addiphdr_t *)asconf->skb->data; |
| 2474 | serial = ntohl(hdr->serial); |
| 2475 | |
| 2476 | /* Skip the addiphdr and store a pointer to address parameter. */ |
| 2477 | length = sizeof(sctp_addiphdr_t); |
| 2478 | addr_param = (union sctp_addr_param *)(asconf->skb->data + length); |
| 2479 | chunk_len -= length; |
| 2480 | |
| 2481 | /* Skip the address parameter and store a pointer to the first |
| 2482 | * asconf paramter. |
| 2483 | */ |
| 2484 | length = ntohs(addr_param->v4.param_hdr.length); |
| 2485 | asconf_param = (sctp_addip_param_t *)((void *)addr_param + length); |
| 2486 | chunk_len -= length; |
| 2487 | |
| 2488 | /* create an ASCONF_ACK chunk. |
| 2489 | * Based on the definitions of parameters, we know that the size of |
| 2490 | * ASCONF_ACK parameters are less than or equal to the twice of ASCONF |
| 2491 | * paramters. |
| 2492 | */ |
| 2493 | asconf_ack = sctp_make_asconf_ack(asoc, serial, chunk_len * 2); |
| 2494 | if (!asconf_ack) |
| 2495 | goto done; |
| 2496 | |
| 2497 | /* Process the TLVs contained within the ASCONF chunk. */ |
| 2498 | while (chunk_len > 0) { |
| 2499 | err_code = sctp_process_asconf_param(asoc, asconf, |
| 2500 | asconf_param); |
| 2501 | /* ADDIP 4.1 A7) |
| 2502 | * If an error response is received for a TLV parameter, |
| 2503 | * all TLVs with no response before the failed TLV are |
| 2504 | * considered successful if not reported. All TLVs after |
| 2505 | * the failed response are considered unsuccessful unless |
| 2506 | * a specific success indication is present for the parameter. |
| 2507 | */ |
| 2508 | if (SCTP_ERROR_NO_ERROR != err_code) |
| 2509 | all_param_pass = 0; |
| 2510 | |
| 2511 | if (!all_param_pass) |
| 2512 | sctp_add_asconf_response(asconf_ack, |
| 2513 | asconf_param->crr_id, err_code, |
| 2514 | asconf_param); |
| 2515 | |
| 2516 | /* ADDIP 4.3 D11) When an endpoint receiving an ASCONF to add |
| 2517 | * an IP address sends an 'Out of Resource' in its response, it |
| 2518 | * MUST also fail any subsequent add or delete requests bundled |
| 2519 | * in the ASCONF. |
| 2520 | */ |
| 2521 | if (SCTP_ERROR_RSRC_LOW == err_code) |
| 2522 | goto done; |
| 2523 | |
| 2524 | /* Move to the next ASCONF param. */ |
| 2525 | length = ntohs(asconf_param->param_hdr.length); |
| 2526 | asconf_param = (sctp_addip_param_t *)((void *)asconf_param + |
| 2527 | length); |
| 2528 | chunk_len -= length; |
| 2529 | } |
| 2530 | |
| 2531 | done: |
| 2532 | asoc->peer.addip_serial++; |
| 2533 | |
| 2534 | /* If we are sending a new ASCONF_ACK hold a reference to it in assoc |
| 2535 | * after freeing the reference to old asconf ack if any. |
| 2536 | */ |
| 2537 | if (asconf_ack) { |
| 2538 | if (asoc->addip_last_asconf_ack) |
| 2539 | sctp_chunk_free(asoc->addip_last_asconf_ack); |
| 2540 | |
| 2541 | sctp_chunk_hold(asconf_ack); |
| 2542 | asoc->addip_last_asconf_ack = asconf_ack; |
| 2543 | } |
| 2544 | |
| 2545 | return asconf_ack; |
| 2546 | } |
| 2547 | |
| 2548 | /* Process a asconf parameter that is successfully acked. */ |
| 2549 | static int sctp_asconf_param_success(struct sctp_association *asoc, |
| 2550 | sctp_addip_param_t *asconf_param) |
| 2551 | { |
| 2552 | struct sctp_af *af; |
| 2553 | union sctp_addr addr; |
| 2554 | struct sctp_bind_addr *bp = &asoc->base.bind_addr; |
| 2555 | union sctp_addr_param *addr_param; |
| 2556 | struct list_head *pos; |
| 2557 | struct sctp_transport *transport; |
| 2558 | int retval = 0; |
| 2559 | |
| 2560 | addr_param = (union sctp_addr_param *) |
| 2561 | ((void *)asconf_param + sizeof(sctp_addip_param_t)); |
| 2562 | |
| 2563 | /* We have checked the packet before, so we do not check again. */ |
| 2564 | af = sctp_get_af_specific(param_type2af(addr_param->v4.param_hdr.type)); |
| 2565 | af->from_addr_param(&addr, addr_param, bp->port, 0); |
| 2566 | |
| 2567 | switch (asconf_param->param_hdr.type) { |
| 2568 | case SCTP_PARAM_ADD_IP: |
| 2569 | sctp_local_bh_disable(); |
| 2570 | sctp_write_lock(&asoc->base.addr_lock); |
| 2571 | retval = sctp_add_bind_addr(bp, &addr, GFP_ATOMIC); |
| 2572 | sctp_write_unlock(&asoc->base.addr_lock); |
| 2573 | sctp_local_bh_enable(); |
| 2574 | break; |
| 2575 | case SCTP_PARAM_DEL_IP: |
| 2576 | sctp_local_bh_disable(); |
| 2577 | sctp_write_lock(&asoc->base.addr_lock); |
| 2578 | retval = sctp_del_bind_addr(bp, &addr); |
| 2579 | sctp_write_unlock(&asoc->base.addr_lock); |
| 2580 | sctp_local_bh_enable(); |
| 2581 | list_for_each(pos, &asoc->peer.transport_addr_list) { |
| 2582 | transport = list_entry(pos, struct sctp_transport, |
| 2583 | transports); |
| 2584 | sctp_transport_route(transport, NULL, |
| 2585 | sctp_sk(asoc->base.sk)); |
| 2586 | } |
| 2587 | break; |
| 2588 | default: |
| 2589 | break; |
| 2590 | } |
| 2591 | |
| 2592 | return retval; |
| 2593 | } |
| 2594 | |
| 2595 | /* Get the corresponding ASCONF response error code from the ASCONF_ACK chunk |
| 2596 | * for the given asconf parameter. If there is no response for this parameter, |
| 2597 | * return the error code based on the third argument 'no_err'. |
| 2598 | * ADDIP 4.1 |
| 2599 | * A7) If an error response is received for a TLV parameter, all TLVs with no |
| 2600 | * response before the failed TLV are considered successful if not reported. |
| 2601 | * All TLVs after the failed response are considered unsuccessful unless a |
| 2602 | * specific success indication is present for the parameter. |
| 2603 | */ |
| 2604 | static __u16 sctp_get_asconf_response(struct sctp_chunk *asconf_ack, |
| 2605 | sctp_addip_param_t *asconf_param, |
| 2606 | int no_err) |
| 2607 | { |
| 2608 | sctp_addip_param_t *asconf_ack_param; |
| 2609 | sctp_errhdr_t *err_param; |
| 2610 | int length; |
| 2611 | int asconf_ack_len = asconf_ack->skb->len; |
| 2612 | __u16 err_code; |
| 2613 | |
| 2614 | if (no_err) |
| 2615 | err_code = SCTP_ERROR_NO_ERROR; |
| 2616 | else |
| 2617 | err_code = SCTP_ERROR_REQ_REFUSED; |
| 2618 | |
| 2619 | /* Skip the addiphdr from the asconf_ack chunk and store a pointer to |
| 2620 | * the first asconf_ack parameter. |
| 2621 | */ |
| 2622 | length = sizeof(sctp_addiphdr_t); |
| 2623 | asconf_ack_param = (sctp_addip_param_t *)(asconf_ack->skb->data + |
| 2624 | length); |
| 2625 | asconf_ack_len -= length; |
| 2626 | |
| 2627 | while (asconf_ack_len > 0) { |
| 2628 | if (asconf_ack_param->crr_id == asconf_param->crr_id) { |
| 2629 | switch(asconf_ack_param->param_hdr.type) { |
| 2630 | case SCTP_PARAM_SUCCESS_REPORT: |
| 2631 | return SCTP_ERROR_NO_ERROR; |
| 2632 | case SCTP_PARAM_ERR_CAUSE: |
| 2633 | length = sizeof(sctp_addip_param_t); |
| 2634 | err_param = (sctp_errhdr_t *) |
| 2635 | ((void *)asconf_ack_param + length); |
| 2636 | asconf_ack_len -= length; |
| 2637 | if (asconf_ack_len > 0) |
| 2638 | return err_param->cause; |
| 2639 | else |
| 2640 | return SCTP_ERROR_INV_PARAM; |
| 2641 | break; |
| 2642 | default: |
| 2643 | return SCTP_ERROR_INV_PARAM; |
| 2644 | } |
| 2645 | } |
| 2646 | |
| 2647 | length = ntohs(asconf_ack_param->param_hdr.length); |
| 2648 | asconf_ack_param = (sctp_addip_param_t *) |
| 2649 | ((void *)asconf_ack_param + length); |
| 2650 | asconf_ack_len -= length; |
| 2651 | } |
| 2652 | |
| 2653 | return err_code; |
| 2654 | } |
| 2655 | |
| 2656 | /* Process an incoming ASCONF_ACK chunk against the cached last ASCONF chunk. */ |
| 2657 | int sctp_process_asconf_ack(struct sctp_association *asoc, |
| 2658 | struct sctp_chunk *asconf_ack) |
| 2659 | { |
| 2660 | struct sctp_chunk *asconf = asoc->addip_last_asconf; |
| 2661 | union sctp_addr_param *addr_param; |
| 2662 | sctp_addip_param_t *asconf_param; |
| 2663 | int length = 0; |
| 2664 | int asconf_len = asconf->skb->len; |
| 2665 | int all_param_pass = 0; |
| 2666 | int no_err = 1; |
| 2667 | int retval = 0; |
| 2668 | __u16 err_code = SCTP_ERROR_NO_ERROR; |
| 2669 | |
| 2670 | /* Skip the chunkhdr and addiphdr from the last asconf sent and store |
| 2671 | * a pointer to address parameter. |
| 2672 | */ |
| 2673 | length = sizeof(sctp_addip_chunk_t); |
| 2674 | addr_param = (union sctp_addr_param *)(asconf->skb->data + length); |
| 2675 | asconf_len -= length; |
| 2676 | |
| 2677 | /* Skip the address parameter in the last asconf sent and store a |
| 2678 | * pointer to the first asconf paramter. |
| 2679 | */ |
| 2680 | length = ntohs(addr_param->v4.param_hdr.length); |
| 2681 | asconf_param = (sctp_addip_param_t *)((void *)addr_param + length); |
| 2682 | asconf_len -= length; |
| 2683 | |
| 2684 | /* ADDIP 4.1 |
| 2685 | * A8) If there is no response(s) to specific TLV parameter(s), and no |
| 2686 | * failures are indicated, then all request(s) are considered |
| 2687 | * successful. |
| 2688 | */ |
| 2689 | if (asconf_ack->skb->len == sizeof(sctp_addiphdr_t)) |
| 2690 | all_param_pass = 1; |
| 2691 | |
| 2692 | /* Process the TLVs contained in the last sent ASCONF chunk. */ |
| 2693 | while (asconf_len > 0) { |
| 2694 | if (all_param_pass) |
| 2695 | err_code = SCTP_ERROR_NO_ERROR; |
| 2696 | else { |
| 2697 | err_code = sctp_get_asconf_response(asconf_ack, |
| 2698 | asconf_param, |
| 2699 | no_err); |
| 2700 | if (no_err && (SCTP_ERROR_NO_ERROR != err_code)) |
| 2701 | no_err = 0; |
| 2702 | } |
| 2703 | |
| 2704 | switch (err_code) { |
| 2705 | case SCTP_ERROR_NO_ERROR: |
| 2706 | retval = sctp_asconf_param_success(asoc, asconf_param); |
| 2707 | break; |
| 2708 | |
| 2709 | case SCTP_ERROR_RSRC_LOW: |
| 2710 | retval = 1; |
| 2711 | break; |
| 2712 | |
| 2713 | case SCTP_ERROR_INV_PARAM: |
| 2714 | /* Disable sending this type of asconf parameter in |
| 2715 | * future. |
| 2716 | */ |
| 2717 | asoc->peer.addip_disabled_mask |= |
| 2718 | asconf_param->param_hdr.type; |
| 2719 | break; |
| 2720 | |
| 2721 | case SCTP_ERROR_REQ_REFUSED: |
| 2722 | case SCTP_ERROR_DEL_LAST_IP: |
| 2723 | case SCTP_ERROR_DEL_SRC_IP: |
| 2724 | default: |
| 2725 | break; |
| 2726 | } |
| 2727 | |
| 2728 | /* Skip the processed asconf parameter and move to the next |
| 2729 | * one. |
| 2730 | */ |
| 2731 | length = ntohs(asconf_param->param_hdr.length); |
| 2732 | asconf_param = (sctp_addip_param_t *)((void *)asconf_param + |
| 2733 | length); |
| 2734 | asconf_len -= length; |
| 2735 | } |
| 2736 | |
| 2737 | /* Free the cached last sent asconf chunk. */ |
| 2738 | sctp_chunk_free(asconf); |
| 2739 | asoc->addip_last_asconf = NULL; |
| 2740 | |
| 2741 | /* Send the next asconf chunk from the addip chunk queue. */ |
| 2742 | asconf = (struct sctp_chunk *)__skb_dequeue(&asoc->addip_chunks); |
| 2743 | if (asconf) { |
| 2744 | /* Hold the chunk until an ASCONF_ACK is received. */ |
| 2745 | sctp_chunk_hold(asconf); |
| 2746 | if (sctp_primitive_ASCONF(asoc, asconf)) |
| 2747 | sctp_chunk_free(asconf); |
| 2748 | else |
| 2749 | asoc->addip_last_asconf = asconf; |
| 2750 | } |
| 2751 | |
| 2752 | return retval; |
| 2753 | } |
| 2754 | |
| 2755 | /* Make a FWD TSN chunk. */ |
| 2756 | struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc, |
| 2757 | __u32 new_cum_tsn, size_t nstreams, |
| 2758 | struct sctp_fwdtsn_skip *skiplist) |
| 2759 | { |
| 2760 | struct sctp_chunk *retval = NULL; |
| 2761 | struct sctp_fwdtsn_chunk *ftsn_chunk; |
| 2762 | struct sctp_fwdtsn_hdr ftsn_hdr; |
| 2763 | struct sctp_fwdtsn_skip skip; |
| 2764 | size_t hint; |
| 2765 | int i; |
| 2766 | |
| 2767 | hint = (nstreams + 1) * sizeof(__u32); |
| 2768 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2769 | retval = sctp_make_chunk(asoc, SCTP_CID_FWD_TSN, 0, hint); |
| 2770 | |
| 2771 | if (!retval) |
| 2772 | return NULL; |
| 2773 | |
| 2774 | ftsn_chunk = (struct sctp_fwdtsn_chunk *)retval->subh.fwdtsn_hdr; |
| 2775 | |
| 2776 | ftsn_hdr.new_cum_tsn = htonl(new_cum_tsn); |
| 2777 | retval->subh.fwdtsn_hdr = |
| 2778 | sctp_addto_chunk(retval, sizeof(ftsn_hdr), &ftsn_hdr); |
| 2779 | |
| 2780 | for (i = 0; i < nstreams; i++) { |
| 2781 | skip.stream = skiplist[i].stream; |
| 2782 | skip.ssn = skiplist[i].ssn; |
| 2783 | sctp_addto_chunk(retval, sizeof(skip), &skip); |
| 2784 | } |
| 2785 | |
| 2786 | return retval; |
| 2787 | } |