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