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                        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 = bp->port;
 165
 166         INIT_LIST_HEAD(&addr->list);
 167         list_add_tail(&addr->list, &bp->address_list);
 168         SCTP_DBG_OBJCNT_INC(addr);
 169
 170         return 0;
 171 }
 172
 173 /* Delete an address from the bind address list in the SCTP_bind_addr
 174  * structure.
 175  */
 176 int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 177 {
 178         struct list_head *pos, *temp;
 179         struct sctp_sockaddr_entry *addr;
 180
 181         list_for_each_safe(pos, temp, &bp->address_list) {
 182                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 183                 if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
 184                         /* Found the exact match. */
 185                         list_del(pos);
 186                         kfree(addr);
 187                         SCTP_DBG_OBJCNT_DEC(addr);
 188
 189                         return 0;
 190                 }
 191         }
 192
 193         return -EINVAL;
 194 }
 195
 196 /* Create a network byte-order representation of all the addresses
 197  * formated as SCTP parameters.
 198  *
 199  * The second argument is the return value for the length.
 200  */
 201 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
 202                                          int *addrs_len,
 203                                          gfp_t gfp)
 204 {
 205         union sctp_params addrparms;
 206         union sctp_params retval;
 207         int addrparms_len;
 208         union sctp_addr_param rawaddr;
 209         int len;
 210         struct sctp_sockaddr_entry *addr;
 211         struct list_head *pos;
 212         struct sctp_af *af;
 213
 214         addrparms_len = 0;
 215         len = 0;
 216
 217         /* Allocate enough memory at once. */
 218         list_for_each(pos, &bp->address_list) {
 219                 len += sizeof(union sctp_addr_param);
 220         }
 221
 222         /* Don't even bother embedding an address if there
 223          * is only one.
 224          */
 225         if (len == sizeof(union sctp_addr_param)) {
 226                 retval.v = NULL;
 227                 goto end_raw;
 228         }
 229
 230         retval.v = kmalloc(len, gfp);
 231         if (!retval.v)
 232                 goto end_raw;
 233
 234         addrparms = retval;
 235
 236         list_for_each(pos, &bp->address_list) {
 237                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 238                 af = sctp_get_af_specific(addr->a.v4.sin_family);
 239                 len = af->to_addr_param(&addr->a, &rawaddr);
 240                 memcpy(addrparms.v, &rawaddr, len);
 241                 addrparms.v += len;
 242                 addrparms_len += len;
 243         }
 244
 245 end_raw:
 246         *addrs_len = addrparms_len;
 247         return retval;
 248 }
 249
 250 /*
 251  * Create an address list out of the raw address list format (IPv4 and IPv6
 252  * address parameters).
 253  */
 254 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
 255                            int addrs_len, __u16 port, gfp_t gfp)
 256 {
 257         union sctp_addr_param *rawaddr;
 258         struct sctp_paramhdr *param;
 259         union sctp_addr addr;
 260         int retval = 0;
 261         int len;
 262         struct sctp_af *af;
 263
 264         /* Convert the raw address to standard address format */
 265         while (addrs_len) {
 266                 param = (struct sctp_paramhdr *)raw_addr_list;
 267                 rawaddr = (union sctp_addr_param *)raw_addr_list;
 268
 269                 af = sctp_get_af_specific(param_type2af(param->type));
 270                 if (unlikely(!af)) {
 271                         retval = -EINVAL;
 272                         sctp_bind_addr_clean(bp);
 273                         break;
 274                 }
 275
 276                 af->from_addr_param(&addr, rawaddr, port, 0);
 277                 retval = sctp_add_bind_addr(bp, &addr, gfp);
 278                 if (retval) {
 279                         /* Can't finish building the list, clean up. */
 280                         sctp_bind_addr_clean(bp);
 281                         break;
 282                 }
 283
 284                 len = ntohs(param->length);
 285                 addrs_len -= len;
 286                 raw_addr_list += len;
 287         }
 288
 289         return retval;
 290 }
 291
 292 /********************************************************************
 293  * 2nd Level Abstractions
 294  ********************************************************************/
 295
 296 /* Does this contain a specified address?  Allow wildcarding. */
 297 int sctp_bind_addr_match(struct sctp_bind_addr *bp,
 298                          const union sctp_addr *addr,
 299                          struct sctp_sock *opt)
 300 {
 301         struct sctp_sockaddr_entry *laddr;
 302         struct list_head *pos;
 303
 304         list_for_each(pos, &bp->address_list) {
 305                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 306                 if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 307                         return 1;
 308         }
 309
 310         return 0;
 311 }
 312
 313 /* Find the first address in the bind address list that is not present in
 314  * the addrs packed array.
 315  */
 316 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
 317                                         const union sctp_addr   *addrs,
 318                                         int                     addrcnt,
 319                                         struct sctp_sock        *opt)
 320 {
 321         struct sctp_sockaddr_entry      *laddr;
 322         union sctp_addr                 *addr;
 323         void                            *addr_buf;
 324         struct sctp_af                  *af;
 325         struct list_head                *pos;
 326         int                             i;
 327
 328         list_for_each(pos, &bp->address_list) {
 329                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 330
 331                 addr_buf = (union sctp_addr *)addrs;
 332                 for (i = 0; i < addrcnt; i++) {
 333                         addr = (union sctp_addr *)addr_buf;
 334                         af = sctp_get_af_specific(addr->v4.sin_family);
 335                         if (!af)
 336                                 return NULL;
 337
 338                         if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 339                                 break;
 340
 341                         addr_buf += af->sockaddr_len;
 342                 }
 343                 if (i == addrcnt)
 344                         return &laddr->a;
 345         }
 346
 347         return NULL;
 348 }
 349
 350 /* Copy out addresses from the global local address list. */
 351 static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
 352                               union sctp_addr *addr,
 353                               sctp_scope_t scope, gfp_t gfp,
 354                               int flags)
 355 {
 356         int error = 0;
 357
 358         if (sctp_is_any(addr)) {
 359                 error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
 360         } else if (sctp_in_scope(addr, scope)) {
 361                 /* Now that the address is in scope, check to see if
 362                  * the address type is supported by local sock as
 363                  * well as the remote peer.
 364                  */
 365                 if ((((AF_INET == addr->sa.sa_family) &&
 366                       (flags & SCTP_ADDR4_PEERSUPP))) ||
 367                     (((AF_INET6 == addr->sa.sa_family) &&
 368                       (flags & SCTP_ADDR6_ALLOWED) &&
 369                       (flags & SCTP_ADDR6_PEERSUPP))))
 370                         error = sctp_add_bind_addr(dest, addr, gfp);
 371         }
 372
 373         return error;
 374 }
 375
 376 /* Is this a wildcard address?  */
 377 int sctp_is_any(const union sctp_addr *addr)
 378 {
 379         struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
 380         if (!af)
 381                 return 0;
 382         return af->is_any(addr);
 383 }
 384
 385 /* Is 'addr' valid for 'scope'?  */
 386 int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
 387 {
 388         sctp_scope_t addr_scope = sctp_scope(addr);
 389
 390         /* The unusable SCTP addresses will not be considered with
 391          * any defined scopes.
 392          */
 393         if (SCTP_SCOPE_UNUSABLE == addr_scope)
 394                 return 0;
 395         /*
 396          * For INIT and INIT-ACK address list, let L be the level of
 397          * of requested destination address, sender and receiver
 398          * SHOULD include all of its addresses with level greater
 399          * than or equal to L.
 400          */
 401         if (addr_scope <= scope)
 402                 return 1;
 403
 404         return 0;
 405 }
 406
 407 /********************************************************************
 408  * 3rd Level Abstractions
 409  ********************************************************************/
 410
 411 /* What is the scope of 'addr'?  */
 412 sctp_scope_t sctp_scope(const union sctp_addr *addr)
 413 {
 414         struct sctp_af *af;
 415
 416         af = sctp_get_af_specific(addr->sa.sa_family);
 417         if (!af)
 418                 return SCTP_SCOPE_UNUSABLE;
 419
 420         return af->scope((union sctp_addr *)addr);
 421 }