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, int gfp, 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, int gfp, int flags)
  67 {
  68         struct sctp_sockaddr_entry *addr;
  69         struct list_head *pos;
  70         int error = 0;
  71
  72         /* All addresses share the same port.  */
  73         dest->port = src->port;
  74
  75         /* Extract the addresses which are relevant for this scope.  */
  76         list_for_each(pos, &src->address_list) {
  77                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
  78                 error = sctp_copy_one_addr(dest, &addr->a, scope,
  79                                            gfp, flags);
  80                 if (error < 0)
  81                         goto out;
  82         }
  83
  84         /* If there are no addresses matching the scope and
  85          * this is global scope, try to get a link scope address, with
  86          * the assumption that we must be sitting behind a NAT.
  87          */
  88         if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
  89                 list_for_each(pos, &src->address_list) {
  90                         addr = list_entry(pos, struct sctp_sockaddr_entry,
  91                                           list);
  92                         error = sctp_copy_one_addr(dest, &addr->a,
  93                                                    SCTP_SCOPE_LINK, gfp,
  94                                                    flags);
  95                         if (error < 0)
  96                                 goto out;
  97                 }
  98         }
  99
 100 out:
 101         if (error)
 102                 sctp_bind_addr_clean(dest);
 103
 104         return error;
 105 }
 106
 107 /* Create a new SCTP_bind_addr from nothing.  */
 108 struct sctp_bind_addr *sctp_bind_addr_new(int gfp)
 109 {
 110         struct sctp_bind_addr *retval;
 111
 112         retval = t_new(struct sctp_bind_addr, gfp);
 113         if (!retval)
 114                 goto nomem;
 115
 116         sctp_bind_addr_init(retval, 0);
 117         retval->malloced = 1;
 118         SCTP_DBG_OBJCNT_INC(bind_addr);
 119
 120 nomem:
 121         return retval;
 122 }
 123
 124 /* Initialize the SCTP_bind_addr structure for either an endpoint or
 125  * an association.
 126  */
 127 void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
 128 {
 129         bp->malloced = 0;
 130
 131         INIT_LIST_HEAD(&bp->address_list);
 132         bp->port = port;
 133 }
 134
 135 /* Dispose of the address list. */
 136 static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
 137 {
 138         struct sctp_sockaddr_entry *addr;
 139         struct list_head *pos, *temp;
 140
 141         /* Empty the bind address list. */
 142         list_for_each_safe(pos, temp, &bp->address_list) {
 143                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 144                 list_del(pos);
 145                 kfree(addr);
 146                 SCTP_DBG_OBJCNT_DEC(addr);
 147         }
 148 }
 149
 150 /* Dispose of an SCTP_bind_addr structure  */
 151 void sctp_bind_addr_free(struct sctp_bind_addr *bp)
 152 {
 153         /* Empty the bind address list. */
 154         sctp_bind_addr_clean(bp);
 155
 156         if (bp->malloced) {
 157                 kfree(bp);
 158                 SCTP_DBG_OBJCNT_DEC(bind_addr);
 159         }
 160 }
 161
 162 /* Add an address to the bind address list in the SCTP_bind_addr structure. */
 163 int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
 164                        int gfp)
 165 {
 166         struct sctp_sockaddr_entry *addr;
 167
 168         /* Add the address to the bind address list.  */
 169         addr = t_new(struct sctp_sockaddr_entry, gfp);
 170         if (!addr)
 171                 return -ENOMEM;
 172
 173         memcpy(&addr->a, new, sizeof(*new));
 174
 175         /* Fix up the port if it has not yet been set.
 176          * Both v4 and v6 have the port at the same offset.
 177          */
 178         if (!addr->a.v4.sin_port)
 179                 addr->a.v4.sin_port = bp->port;
 180
 181         INIT_LIST_HEAD(&addr->list);
 182         list_add_tail(&addr->list, &bp->address_list);
 183         SCTP_DBG_OBJCNT_INC(addr);
 184
 185         return 0;
 186 }
 187
 188 /* Delete an address from the bind address list in the SCTP_bind_addr
 189  * structure.
 190  */
 191 int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
 192 {
 193         struct list_head *pos, *temp;
 194         struct sctp_sockaddr_entry *addr;
 195
 196         list_for_each_safe(pos, temp, &bp->address_list) {
 197                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 198                 if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
 199                         /* Found the exact match. */
 200                         list_del(pos);
 201                         kfree(addr);
 202                         SCTP_DBG_OBJCNT_DEC(addr);
 203
 204                         return 0;
 205                 }
 206         }
 207
 208         return -EINVAL;
 209 }
 210
 211 /* Create a network byte-order representation of all the addresses
 212  * formated as SCTP parameters.
 213  *
 214  * The second argument is the return value for the length.
 215  */
 216 union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
 217                                          int *addrs_len, int gfp)
 218 {
 219         union sctp_params addrparms;
 220         union sctp_params retval;
 221         int addrparms_len;
 222         union sctp_addr_param rawaddr;
 223         int len;
 224         struct sctp_sockaddr_entry *addr;
 225         struct list_head *pos;
 226         struct sctp_af *af;
 227
 228         addrparms_len = 0;
 229         len = 0;
 230
 231         /* Allocate enough memory at once. */
 232         list_for_each(pos, &bp->address_list) {
 233                 len += sizeof(union sctp_addr_param);
 234         }
 235
 236         /* Don't even bother embedding an address if there
 237          * is only one.
 238          */
 239         if (len == sizeof(union sctp_addr_param)) {
 240                 retval.v = NULL;
 241                 goto end_raw;
 242         }
 243
 244         retval.v = kmalloc(len, gfp);
 245         if (!retval.v)
 246                 goto end_raw;
 247
 248         addrparms = retval;
 249
 250         list_for_each(pos, &bp->address_list) {
 251                 addr = list_entry(pos, struct sctp_sockaddr_entry, list);
 252                 af = sctp_get_af_specific(addr->a.v4.sin_family);
 253                 len = af->to_addr_param(&addr->a, &rawaddr);
 254                 memcpy(addrparms.v, &rawaddr, len);
 255                 addrparms.v += len;
 256                 addrparms_len += len;
 257         }
 258
 259 end_raw:
 260         *addrs_len = addrparms_len;
 261         return retval;
 262 }
 263
 264 /*
 265  * Create an address list out of the raw address list format (IPv4 and IPv6
 266  * address parameters).
 267  */
 268 int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
 269                            int addrs_len, __u16 port, int gfp)
 270 {
 271         union sctp_addr_param *rawaddr;
 272         struct sctp_paramhdr *param;
 273         union sctp_addr addr;
 274         int retval = 0;
 275         int len;
 276         struct sctp_af *af;
 277
 278         /* Convert the raw address to standard address format */
 279         while (addrs_len) {
 280                 param = (struct sctp_paramhdr *)raw_addr_list;
 281                 rawaddr = (union sctp_addr_param *)raw_addr_list;
 282
 283                 af = sctp_get_af_specific(param_type2af(param->type));
 284                 if (unlikely(!af)) {
 285                         retval = -EINVAL;
 286                         sctp_bind_addr_clean(bp);
 287                         break;
 288                 }
 289
 290                 af->from_addr_param(&addr, rawaddr, port, 0);
 291                 retval = sctp_add_bind_addr(bp, &addr, gfp);
 292                 if (retval) {
 293                         /* Can't finish building the list, clean up. */
 294                         sctp_bind_addr_clean(bp);
 295                         break;
 296                 }
 297
 298                 len = ntohs(param->length);
 299                 addrs_len -= len;
 300                 raw_addr_list += len;
 301         }
 302
 303         return retval;
 304 }
 305
 306 /********************************************************************
 307  * 2nd Level Abstractions
 308  ********************************************************************/
 309
 310 /* Does this contain a specified address?  Allow wildcarding. */
 311 int sctp_bind_addr_match(struct sctp_bind_addr *bp,
 312                          const union sctp_addr *addr,
 313                          struct sctp_opt *opt)
 314 {
 315         struct sctp_sockaddr_entry *laddr;
 316         struct list_head *pos;
 317
 318         list_for_each(pos, &bp->address_list) {
 319                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 320                 if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 321                         return 1;
 322         }
 323
 324         return 0;
 325 }
 326
 327 /* Find the first address in the bind address list that is not present in
 328  * the addrs packed array.
 329  */
 330 union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr   *bp,
 331                                         const union sctp_addr   *addrs,
 332                                         int                     addrcnt,
 333                                         struct sctp_opt         *opt)
 334 {
 335         struct sctp_sockaddr_entry      *laddr;
 336         union sctp_addr                 *addr;
 337         void                            *addr_buf;
 338         struct sctp_af                  *af;
 339         struct list_head                *pos;
 340         int                             i;
 341
 342         list_for_each(pos, &bp->address_list) {
 343                 laddr = list_entry(pos, struct sctp_sockaddr_entry, list);
 344
 345                 addr_buf = (union sctp_addr *)addrs;
 346                 for (i = 0; i < addrcnt; i++) {
 347                         addr = (union sctp_addr *)addr_buf;
 348                         af = sctp_get_af_specific(addr->v4.sin_family);
 349                         if (!af)
 350                                 return NULL;
 351
 352                         if (opt->pf->cmp_addr(&laddr->a, addr, opt))
 353                                 break;
 354
 355                         addr_buf += af->sockaddr_len;
 356                 }
 357                 if (i == addrcnt)
 358                         return &laddr->a;
 359         }
 360
 361         return NULL;
 362 }
 363
 364 /* Copy out addresses from the global local address list. */
 365 static int sctp_copy_one_addr(struct sctp_bind_addr *dest,
 366                               union sctp_addr *addr,
 367                               sctp_scope_t scope, int gfp, int flags)
 368 {
 369         int error = 0;
 370
 371         if (sctp_is_any(addr)) {
 372                 error = sctp_copy_local_addr_list(dest, scope, gfp, flags);
 373         } else if (sctp_in_scope(addr, scope)) {
 374                 /* Now that the address is in scope, check to see if
 375                  * the address type is supported by local sock as
 376                  * well as the remote peer.
 377                  */
 378                 if ((((AF_INET == addr->sa.sa_family) &&
 379                       (flags & SCTP_ADDR4_PEERSUPP))) ||
 380                     (((AF_INET6 == addr->sa.sa_family) &&
 381                       (flags & SCTP_ADDR6_ALLOWED) &&
 382                       (flags & SCTP_ADDR6_PEERSUPP))))
 383                         error = sctp_add_bind_addr(dest, addr, gfp);
 384         }
 385
 386         return error;
 387 }
 388
 389 /* Is this a wildcard address?  */
 390 int sctp_is_any(const union sctp_addr *addr)
 391 {
 392         struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
 393         if (!af)
 394                 return 0;
 395         return af->is_any(addr);
 396 }
 397
 398 /* Is 'addr' valid for 'scope'?  */
 399 int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
 400 {
 401         sctp_scope_t addr_scope = sctp_scope(addr);
 402
 403         /* The unusable SCTP addresses will not be considered with
 404          * any defined scopes.
 405          */
 406         if (SCTP_SCOPE_UNUSABLE == addr_scope)
 407                 return 0;
 408         /*
 409          * For INIT and INIT-ACK address list, let L be the level of
 410          * of requested destination address, sender and receiver
 411          * SHOULD include all of its addresses with level greater
 412          * than or equal to L.
 413          */
 414         if (addr_scope <= scope)
 415                 return 1;
 416
 417         return 0;
 418 }
 419
 420 /********************************************************************
 421  * 3rd Level Abstractions
 422  ********************************************************************/
 423
 424 /* What is the scope of 'addr'?  */
 425 sctp_scope_t sctp_scope(const union sctp_addr *addr)
 426 {
 427         struct sctp_af *af;
 428
 429         af = sctp_get_af_specific(addr->sa.sa_family);
 430         if (!af)
 431                 return SCTP_SCOPE_UNUSABLE;
 432
 433         return af->scope((union sctp_addr *)addr);
 434 }