net/sctp/bind_addr.c

   1 /* SCTP kernel reference Implementation
   2  * (C) Copyright IBM Corp. 2001, 2003
   3  * Copyright (c) Cisco 1999,2000
   4  * Copyright (c) Motorola 1999,2000,2001
   5  * Copyright (c) La Monte H.P. Yarroll 2001
   6  *
   7  * This file is part of the SCTP kernel reference implementation.
   8  *
   9  * A collection class to handle the storage of transport addresses.
  10  *
  11  * The SCTP reference implementation is free software;
  12  * you can redistribute it and/or modify it under the terms of
  13  * the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2, or (at your option)
  15  * any later version.
  16  *
  17  * The SCTP reference implementation is distributed in the hope that it
  18  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  19  *                 ************************
  20  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  21  * See the GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with GNU CC; see the file COPYING.  If not, write to
  25  * the Free Software Foundation, 59 Temple Place - Suite 330,
  26  * Boston, MA 02111-1307, USA.
  27  *
  28  * Please send any bug reports or fixes you make to the
  29  * email address(es):
  30  *    lksctp developers <lksctp-developers@lists.sourceforge.net>
  31  *
  32  * Or submit a bug report through the following website:
  33  *    http://www.sf.net/projects/lksctp
  34  *
  35  * Written or modified by:
  36  *    La Monte H.P. Yarroll <piggy@acm.org>
  37  *    Karl Knutson          <karl@athena.chicago.il.us>
  38  *    Jon Grimm             <jgrimm@us.ibm.com>
  39  *    Daisy Chang           <daisyc@us.ibm.com>
  40  *
  41  * Any bugs reported given to us we will try to fix... any fixes shared will
  42  * be incorporated into the next SCTP release.
  43  */
  44
  45 #include <linux/types.h>
  46 #include <linux/sched.h>
  47 #include <linux/in.h>
  48 #include <net/sock.h>
  49 #include <net/ipv6.h>
  50 #include <net/if_inet6.h>
  51 #include <net/sctp/sctp.h>
  52 #include <net/sctp/sm.h>
  53
  54 /* Forward declarations for internal helpers. */
  55 static int sctp_copy_one_addr(struct sctp_bind_addr *, union sctp_addr *,
  56                               sctp_scope_t scope, gfp_t gfp,
  57                               int flags);
  58 static void sctp_bind_addr_clean(struct sctp_bind_addr *);
  59
  60 /* First Level Abstractions. */
  61
  62 /* Copy 'src' to 'dest' taking 'scope' into account.  Omit addresses
  63  * in 'src' which have a broader scope than 'scope'.
  64  */
  65 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
  66                         const struct sctp_bind_addr *src,
  67                         sctp_scope_t scope, gfp_t gfp,
  68                         int flags)
  69 {
  70         struct sctp_sockaddr_entry *addr;
  71         struct list_head *pos;
  72         int error = 0;
  73
  74         /* All addresses share the same port.  */
  75         dest->port = src->port;
  76
  77         /* Extract the addresses which are relevant for this scope.  */
  78         list_for_each(pos, &src->address_list) {
  79                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
  80                 error = sctp_copy_one_addr(dest, &addr->a, scope,
  81                                            gfp, flags);
  82                 if (error < 0)
  83                         goto out;
  84         }
  85
  86         /* If there are no addresses matching the scope and
  87          * this is global scope, try to get a link scope address, with
  88          * the assumption that we must be sitting behind a NAT.
  89          */
  90         if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
  91                 list_for_each(pos, &src->address_list) {
  92                         addr = list_entry(pos, struct sctp_sockaddr_entry,
  93                                           list);
  94                         error = sctp_copy_one_addr(dest, &addr->a,
  95                                                    SCTP_SCOPE_LINK, gfp,
  96                                                    flags);
  97                         if (error < 0)
  98                                 goto out;
  99                 }
 100         }
 101
 102 out:
 103         if (error)
 104                 sctp_bind_addr_clean(dest);
 105
 106         return error;
 107 }
 108
 109 /* Initialize the SCTP_bind_addr structure for either an endpoint or
 110  * an association.
 111  */
 112 void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
 113 {
 114         bp->malloced = 0;
 115
 116         INIT_LIST_HEAD(&bp->address_list);
 117         bp->port = port;
 118 }
 119
 120 /* Dispose of the address list. */
 121 static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
 122 {
 123         struct sctp_sockaddr_entry *addr;
 124         struct list_head *pos, *temp;
 125
 126         /* Empty the bind address list. */
 127         list_for_each_safe(pos, temp, &bp->address_list) {
 128                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 129                 list_del(pos);
 130                 kfree(addr);
 131                 SCTP_DBG_OBJCNT_DEC(addr);
 132         }
 133 }
 134
 135 /* Dispose of an SCTP_bind_addr structure  */
 136 void sctp_bind_addr_free(struct sctp_bind_addr *bp)
 137 {
 138         /* Empty the bind address list. */
 139         sctp_bind_addr_clean(bp);
 140
 141         if (bp->malloced) {
 142                 kfree(bp);
 143                 SCTP_DBG_OBJCNT_DEC(bind_addr);
 144         }
 145 }
 146
 147 /* Add an address to the bind address list in the SCTP_bind_addr structure. */
 148 int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
 149                        __u8 use_as_src, gfp_t gfp)
 150 {
 151         struct sctp_sockaddr_entry *addr;
 152
 153         /* Add the address to the bind address list.  */
 154         addr = t_new(struct sctp_sockaddr_entry, gfp);
 155         if (!addr)
 156                 return -ENOMEM;
 157
 158         memcpy(&addr->a, new, sizeof(*new));
 159
 160         /* Fix up the port if it has not yet been set.
 161          * Both v4 and v6 have the port at the same offset.
 162          */
 163         if (!addr->a.v4.sin_port)
 164                 addr->a.v4.sin_port = htons(bp->port);
 165
 166         addr->use_as_src = use_as_src;
 167
 168         INIT_LIST_HEAD(&addr->list);
 169         list_add_tail(&addr->list, &bp->address_list);
 170         SCTP_DBG_OBJCNT_INC(addr);
 171
 172         return 0;
 173 }
 174
 175 /* Delete an address from the bind address list in the SCTP_bind_addr
 176  * structure.
 177  */
 178 int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 179 {
 180         struct list_head *pos, *temp;
 181         struct sctp_sockaddr_entry *addr;
 182
 183         list_for_each_safe(pos, temp, &bp->address_list) {
 184                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 185                 if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
 186                         /* Found the exact match. */
 187                         list_del(pos);
 188                         kfree(addr);
 189                         SCTP_DBG_OBJCNT_DEC(addr);
 190
 191                         return 0;
 192                 }
 193         }
 194
 195         return -EINVAL;
 196 }
 197
 198 /* Create a network byte-order representation of all the addresses
 199  * formated as SCTP parameters.
 200  *
 201  * The second argument is the return value for the length.
 202  */
 203 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
 204                                          int *addrs_len,
 205                                          gfp_t gfp)
 206 {
 207         union sctp_params addrparms;
 208         union sctp_params retval;
 209         int addrparms_len;
 210         union sctp_addr_param rawaddr;
 211         int len;
 212         struct sctp_sockaddr_entry *addr;
 213         struct list_head *pos;
 214         struct sctp_af *af;
 215
 216         addrparms_len = 0;
 217         len = 0;
 218
 219         /* Allocate enough memory at once. */
 220         list_for_each(pos, &bp->address_list) {
 221                 len += sizeof(union sctp_addr_param);
 222         }
 223
 224         /* Don't even bother embedding an address if there
 225          * is only one.
 226          */
 227         if (len == sizeof(union sctp_addr_param)) {
 228                 retval.v = NULL;
 229                 goto end_raw;
 230         }
 231
 232         retval.v = kmalloc(len, gfp);
 233         if (!retval.v)
 234                 goto end_raw;
 235
 236         addrparms = retval;
 237
 238         list_for_each(pos, &bp->address_list) {
 239                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 240                 af = sctp_get_af_specific(addr->a.v4.sin_family);
 241                 len = af->to_addr_param(&addr->a, &rawaddr);
 242                 memcpy(addrparms.v, &rawaddr, len);
 243                 addrparms.v += len;
 244                 addrparms_len += len;
 245         }
 246
 247 end_raw:
 248         *addrs_len = addrparms_len;
 249         return retval;
 250 }
 251
 252 /*
 253  * Create an address list out of the raw address list format (IPv4 and IPv6
 254  * address parameters).
 255  */
 256 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
 257                            int addrs_len, __u16 port, gfp_t gfp)
 258 {
 259         union sctp_addr_param *rawaddr;
 260         struct sctp_paramhdr *param;
 261         union sctp_addr addr;
 262         int retval = 0;
 263         int len;
 264         struct sctp_af *af;
 265
 266         /* Convert the raw address to standard address format */
 267         while (addrs_len) {
 268                 param = (struct sctp_paramhdr *)raw_addr_list;
 269                 rawaddr = (union sctp_addr_param *)raw_addr_list;
 270
 271                 af = sctp_get_af_specific(param_type2af(param->type));
 272                 if (unlikely(!af)) {
 273                         retval = -EINVAL;
 274                         sctp_bind_addr_clean(bp);
 275                         break;
 276                 }
 277
 278                 af->from_addr_param(&addr, rawaddr, htons(port), 0);
 279                 retval = sctp_add_bind_addr(bp, &addr, 1, gfp);
 280                 if (retval) {
 281                         /* Can't finish building the list, clean up. */
 282                         sctp_bind_addr_clean(bp);
 283                         break;
 284                 }
 285
 286                 len = ntohs(param->length);
 287                 addrs_len -= len;
 288                 raw_addr_list += len;
 289         }
 290
 291         return retval;
 292 }
 293
 294 /********************************************************************
 295  * 2nd Level Abstractions
 296  ********************************************************************/
 297
 298 /* Does this contain a specified address?  Allow wildcarding. */
 299 int sctp_bind_addr_match(struct sctp_bind_addr *bp,
 300                          const union sctp_addr *addr,
 301                          struct sctp_sock *opt)
 302 {
 303         struct sctp_sockaddr_entry *laddr;
 304         struct list_head *pos;
 305
 306         list_for_each(pos, &bp->address_list) {
 307                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 308                 if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 309                         return 1;
 310         }
 311
 312         return 0;
 313 }
 314
 315 /* Find the first address in the bind address list that is not present in
 316  * the addrs packed array.
 317  */
 318 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
 319                                         const union sctp_addr   *addrs,
 320                                         int                     addrcnt,
 321                                         struct sctp_sock        *opt)
 322 {
 323         struct sctp_sockaddr_entry      *laddr;
 324         union sctp_addr                 *addr;
 325         void                            *addr_buf;
 326         struct sctp_af                  *af;
 327         struct list_head                *pos;
 328         int                             i;
 329
 330         list_for_each(pos, &bp->address_list) {
 331                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 332
 333                 addr_buf = (union sctp_addr *)addrs;
 334                 for (i = 0; i < addrcnt; i++) {
 335                         addr = (union sctp_addr *)addr_buf;
 336                         af = sctp_get_af_specific(addr->v4.sin_family);
 337                         if (!af)
 338                                 return NULL;
 339
 340                         if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 341                                 break;
 342
 343                         addr_buf += af->sockaddr_len;
 344                 }
 345                 if (i == addrcnt)
 346                         return &laddr->a;
 347         }
 348
 349         return NULL;
 350 }
 351
 352 /* Copy out addresses from the global local address list. */
 353 static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
 354                               union sctp_addr *addr,
 355                               sctp_scope_t scope, gfp_t gfp,
 356                               int flags)
 357 {
 358         int error = 0;
 359
 360         if (sctp_is_any(addr)) {
 361                 error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
 362         } else if (sctp_in_scope(addr, scope)) {
 363                 /* Now that the address is in scope, check to see if
 364                  * the address type is supported by local sock as
 365                  * well as the remote peer.
 366                  */
 367                 if ((((AF_INET == addr->sa.sa_family) &&
 368                       (flags & SCTP_ADDR4_PEERSUPP))) ||
 369                     (((AF_INET6 == addr->sa.sa_family) &&
 370                       (flags & SCTP_ADDR6_ALLOWED) &&
 371                       (flags & SCTP_ADDR6_PEERSUPP))))
 372                         error = sctp_add_bind_addr(dest, addr, 1, gfp);
 373         }
 374
 375         return error;
 376 }
 377
 378 /* Is this a wildcard address?  */
 379 int sctp_is_any(const union sctp_addr *addr)
 380 {
 381         struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
 382         if (!af)
 383                 return 0;
 384         return af->is_any(addr);
 385 }
 386
 387 /* Is 'addr' valid for 'scope'?  */
 388 int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
 389 {
 390         sctp_scope_t addr_scope = sctp_scope(addr);
 391
 392         /* The unusable SCTP addresses will not be considered with
 393          * any defined scopes.
 394          */
 395         if (SCTP_SCOPE_UNUSABLE == addr_scope)
 396                 return 0;
 397         /*
 398          * For INIT and INIT-ACK address list, let L be the level of
 399          * of requested destination address, sender and receiver
 400          * SHOULD include all of its addresses with level greater
 401          * than or equal to L.
 402          */
 403         if (addr_scope <= scope)
 404                 return 1;
 405
 406         return 0;
 407 }
 408
 409 /********************************************************************
 410  * 3rd Level Abstractions
 411  ********************************************************************/
 412
 413 /* What is the scope of 'addr'?  */
 414 sctp_scope_t sctp_scope(const union sctp_addr *addr)
 415 {
 416         struct sctp_af *af;
 417
 418         af = sctp_get_af_specific(addr->sa.sa_family);
 419         if (!af)
 420                 return SCTP_SCOPE_UNUSABLE;
 421
 422         return af->scope((union sctp_addr *)addr);
 423 }