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/in.h>
  47 #include <net/sock.h>
  48 #include <net/ipv6.h>
  49 #include <net/if_inet6.h>
  50 #include <net/sctp/sctp.h>
  51 #include <net/sctp/sm.h>
  52
  53 /* Forward declarations for internal helpers. */
  54 static int sctp_copy_one_addr(struct sctp_bind_addr *, union sctp_addr *,
  55                               sctp_scope_t scope, gfp_t gfp,
  56                               int flags);
  57 static void sctp_bind_addr_clean(struct sctp_bind_addr *);
  58
  59 /* First Level Abstractions. */
  60
  61 /* Copy 'src' to 'dest' taking 'scope' into account.  Omit addresses
  62  * in 'src' which have a broader scope than 'scope'.
  63  */
  64 int sctp_bind_addr_copy(struct sctp_bind_addr *dest,
  65                         const struct sctp_bind_addr *src,
  66                         sctp_scope_t scope, gfp_t gfp,
  67                         int flags)
  68 {
  69         struct sctp_sockaddr_entry *addr;
  70         struct list_head *pos;
  71         int error = 0;
  72
  73         /* All addresses share the same port.  */
  74         dest->port = src->port;
  75
  76         /* Extract the addresses which are relevant for this scope.  */
  77         list_for_each(pos, &src->address_list) {
  78                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
  79                 error = sctp_copy_one_addr(dest, &addr->a, scope,
  80                                            gfp, flags);
  81                 if (error < 0)
  82                         goto out;
  83         }
  84
  85         /* If there are no addresses matching the scope and
  86          * this is global scope, try to get a link scope address, with
  87          * the assumption that we must be sitting behind a NAT.
  88          */
  89         if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
  90                 list_for_each(pos, &src->address_list) {
  91                         addr = list_entry(pos, struct sctp_sockaddr_entry,
  92                                           list);
  93                         error = sctp_copy_one_addr(dest, &addr->a,
  94                                                    SCTP_SCOPE_LINK, gfp,
  95                                                    flags);
  96                         if (error < 0)
  97                                 goto out;
  98                 }
  99         }
 100
 101 out:
 102         if (error)
 103                 sctp_bind_addr_clean(dest);
 104
 105         return error;
 106 }
 107
 108 /* Initialize the SCTP_bind_addr structure for either an endpoint or
 109  * an association.
 110  */
 111 void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
 112 {
 113         bp->malloced = 0;
 114
 115         INIT_LIST_HEAD(&bp->address_list);
 116         bp->port = port;
 117 }
 118
 119 /* Dispose of the address list. */
 120 static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
 121 {
 122         struct sctp_sockaddr_entry *addr;
 123         struct list_head *pos, *temp;
 124
 125         /* Empty the bind address list. */
 126         list_for_each_safe(pos, temp, &bp->address_list) {
 127                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 128                 list_del(pos);
 129                 kfree(addr);
 130                 SCTP_DBG_OBJCNT_DEC(addr);
 131         }
 132 }
 133
 134 /* Dispose of an SCTP_bind_addr structure  */
 135 void sctp_bind_addr_free(struct sctp_bind_addr *bp)
 136 {
 137         /* Empty the bind address list. */
 138         sctp_bind_addr_clean(bp);
 139
 140         if (bp->malloced) {
 141                 kfree(bp);
 142                 SCTP_DBG_OBJCNT_DEC(bind_addr);
 143         }
 144 }
 145
 146 /* Add an address to the bind address list in the SCTP_bind_addr structure. */
 147 int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
 148                        __u8 use_as_src, gfp_t gfp)
 149 {
 150         struct sctp_sockaddr_entry *addr;
 151
 152         /* Add the address to the bind address list.  */
 153         addr = t_new(struct sctp_sockaddr_entry, gfp);
 154         if (!addr)
 155                 return -ENOMEM;
 156
 157         memcpy(&addr->a, new, sizeof(*new));
 158
 159         /* Fix up the port if it has not yet been set.
 160          * Both v4 and v6 have the port at the same offset.
 161          */
 162         if (!addr->a.v4.sin_port)
 163                 addr->a.v4.sin_port = htons(bp->port);
 164
 165         addr->use_as_src = use_as_src;
 166
 167         INIT_LIST_HEAD(&addr->list);
 168         list_add_tail(&addr->list, &bp->address_list);
 169         SCTP_DBG_OBJCNT_INC(addr);
 170
 171         return 0;
 172 }
 173
 174 /* Delete an address from the bind address list in the SCTP_bind_addr
 175  * structure.
 176  */
 177 int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 178 {
 179         struct list_head *pos, *temp;
 180         struct sctp_sockaddr_entry *addr;
 181
 182         list_for_each_safe(pos, temp, &bp->address_list) {
 183                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 184                 if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
 185                         /* Found the exact match. */
 186                         list_del(pos);
 187                         kfree(addr);
 188                         SCTP_DBG_OBJCNT_DEC(addr);
 189
 190                         return 0;
 191                 }
 192         }
 193
 194         return -EINVAL;
 195 }
 196
 197 /* Create a network byte-order representation of all the addresses
 198  * formated as SCTP parameters.
 199  *
 200  * The second argument is the return value for the length.
 201  */
 202 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
 203                                          int *addrs_len,
 204                                          gfp_t gfp)
 205 {
 206         union sctp_params addrparms;
 207         union sctp_params retval;
 208         int addrparms_len;
 209         union sctp_addr_param rawaddr;
 210         int len;
 211         struct sctp_sockaddr_entry *addr;
 212         struct list_head *pos;
 213         struct sctp_af *af;
 214
 215         addrparms_len = 0;
 216         len = 0;
 217
 218         /* Allocate enough memory at once. */
 219         list_for_each(pos, &bp->address_list) {
 220                 len += sizeof(union sctp_addr_param);
 221         }
 222
 223         /* Don't even bother embedding an address if there
 224          * is only one.
 225          */
 226         if (len == sizeof(union sctp_addr_param)) {
 227                 retval.v = NULL;
 228                 goto end_raw;
 229         }
 230
 231         retval.v = kmalloc(len, gfp);
 232         if (!retval.v)
 233                 goto end_raw;
 234
 235         addrparms = retval;
 236
 237         list_for_each(pos, &bp->address_list) {
 238                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 239                 af = sctp_get_af_specific(addr->a.v4.sin_family);
 240                 len = af->to_addr_param(&addr->a, &rawaddr);
 241                 memcpy(addrparms.v, &rawaddr, len);
 242                 addrparms.v += len;
 243                 addrparms_len += len;
 244         }
 245
 246 end_raw:
 247         *addrs_len = addrparms_len;
 248         return retval;
 249 }
 250
 251 /*
 252  * Create an address list out of the raw address list format (IPv4 and IPv6
 253  * address parameters).
 254  */
 255 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
 256                            int addrs_len, __u16 port, gfp_t gfp)
 257 {
 258         union sctp_addr_param *rawaddr;
 259         struct sctp_paramhdr *param;
 260         union sctp_addr addr;
 261         int retval = 0;
 262         int len;
 263         struct sctp_af *af;
 264
 265         /* Convert the raw address to standard address format */
 266         while (addrs_len) {
 267                 param = (struct sctp_paramhdr *)raw_addr_list;
 268                 rawaddr = (union sctp_addr_param *)raw_addr_list;
 269
 270                 af = sctp_get_af_specific(param_type2af(param->type));
 271                 if (unlikely(!af)) {
 272                         retval = -EINVAL;
 273                         sctp_bind_addr_clean(bp);
 274                         break;
 275                 }
 276
 277                 af->from_addr_param(&addr, rawaddr, htons(port), 0);
 278                 retval = sctp_add_bind_addr(bp, &addr, 1, gfp);
 279                 if (retval) {
 280                         /* Can't finish building the list, clean up. */
 281                         sctp_bind_addr_clean(bp);
 282                         break;
 283                 }
 284
 285                 len = ntohs(param->length);
 286                 addrs_len -= len;
 287                 raw_addr_list += len;
 288         }
 289
 290         return retval;
 291 }
 292
 293 /********************************************************************
 294  * 2nd Level Abstractions
 295  ********************************************************************/
 296
 297 /* Does this contain a specified address?  Allow wildcarding. */
 298 int sctp_bind_addr_match(struct sctp_bind_addr *bp,
 299                          const union sctp_addr *addr,
 300                          struct sctp_sock *opt)
 301 {
 302         struct sctp_sockaddr_entry *laddr;
 303         struct list_head *pos;
 304
 305         list_for_each(pos, &bp->address_list) {
 306                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 307                 if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 308                         return 1;
 309         }
 310
 311         return 0;
 312 }
 313
 314 /* Find the first address in the bind address list that is not present in
 315  * the addrs packed array.
 316  */
 317 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
 318                                         const union sctp_addr   *addrs,
 319                                         int                     addrcnt,
 320                                         struct sctp_sock        *opt)
 321 {
 322         struct sctp_sockaddr_entry      *laddr;
 323         union sctp_addr                 *addr;
 324         void                            *addr_buf;
 325         struct sctp_af                  *af;
 326         struct list_head                *pos;
 327         int                             i;
 328
 329         list_for_each(pos, &bp->address_list) {
 330                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 331
 332                 addr_buf = (union sctp_addr *)addrs;
 333                 for (i = 0; i < addrcnt; i++) {
 334                         addr = (union sctp_addr *)addr_buf;
 335                         af = sctp_get_af_specific(addr->v4.sin_family);
 336                         if (!af)
 337                                 return NULL;
 338
 339                         if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 340                                 break;
 341
 342                         addr_buf += af->sockaddr_len;
 343                 }
 344                 if (i == addrcnt)
 345                         return &laddr->a;
 346         }
 347
 348         return NULL;
 349 }
 350
 351 /* Copy out addresses from the global local address list. */
 352 static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
 353                               union sctp_addr *addr,
 354                               sctp_scope_t scope, gfp_t gfp,
 355                               int flags)
 356 {
 357         int error = 0;
 358
 359         if (sctp_is_any(addr)) {
 360                 error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
 361         } else if (sctp_in_scope(addr, scope)) {
 362                 /* Now that the address is in scope, check to see if
 363                  * the address type is supported by local sock as
 364                  * well as the remote peer.
 365                  */
 366                 if ((((AF_INET == addr->sa.sa_family) &&
 367                       (flags & SCTP_ADDR4_PEERSUPP))) ||
 368                     (((AF_INET6 == addr->sa.sa_family) &&
 369                       (flags & SCTP_ADDR6_ALLOWED) &&
 370                       (flags & SCTP_ADDR6_PEERSUPP))))
 371                         error = sctp_add_bind_addr(dest, addr, 1, gfp);
 372         }
 373
 374         return error;
 375 }
 376
 377 /* Is this a wildcard address?  */
 378 int sctp_is_any(const union sctp_addr *addr)
 379 {
 380         struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
 381         if (!af)
 382                 return 0;
 383         return af->is_any(addr);
 384 }
 385
 386 /* Is 'addr' valid for 'scope'?  */
 387 int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
 388 {
 389         sctp_scope_t addr_scope = sctp_scope(addr);
 390
 391         /* The unusable SCTP addresses will not be considered with
 392          * any defined scopes.
 393          */
 394         if (SCTP_SCOPE_UNUSABLE == addr_scope)
 395                 return 0;
 396         /*
 397          * For INIT and INIT-ACK address list, let L be the level of
 398          * of requested destination address, sender and receiver
 399          * SHOULD include all of its addresses with level greater
 400          * than or equal to L.
 401          */
 402         if (addr_scope <= scope)
 403                 return 1;
 404
 405         return 0;
 406 }
 407
 408 /********************************************************************
 409  * 3rd Level Abstractions
 410  ********************************************************************/
 411
 412 /* What is the scope of 'addr'?  */
 413 sctp_scope_t sctp_scope(const union sctp_addr *addr)
 414 {
 415         struct sctp_af *af;
 416
 417         af = sctp_get_af_specific(addr->sa.sa_family);
 418         if (!af)
 419                 return SCTP_SCOPE_UNUSABLE;
 420
 421         return af->scope((union sctp_addr *)addr);
 422 }