sys/netinet6/scope6.c

   1 /*      $FreeBSD: src/sys/netinet6/scope6.c,v 1.1.2.3 2002/04/01 15:29:04 ume Exp $     */
   2 /*      $DragonFly: src/sys/netinet6/scope6.c,v 1.11 2008/01/05 14:02:40 swildner Exp $ */
   3 /*      $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ */
   4
   5 /*
   6  * Copyright (C) 2000 WIDE Project.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the project nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/malloc.h>
  36 #include <sys/mbuf.h>
  37 #include <sys/socket.h>
  38 #include <sys/systm.h>
  39 #include <sys/queue.h>
  40 #include <sys/thread2.h>
  41
  42 #include <net/route.h>
  43 #include <net/if.h>
  44
  45 #include <netinet/in.h>
  46
  47 #include <netinet6/in6_var.h>
  48 #include <netinet6/scope6_var.h>
  49
  50 static struct scope6_id sid_default;
  51
  52 static __inline
  53 struct scope6_id *
  54 SID(struct ifnet *ifp)
  55 {
  56         struct in6_ifextra *xtra;
  57
  58         xtra = ifp->if_afdata[AF_INET6];
  59         if (xtra)
  60                 return (xtra->scope6_id);
  61         return(NULL);
  62 }
  63
  64 void
  65 scope6_init(void)
  66 {
  67         bzero(&sid_default, sizeof(sid_default));
  68 }
  69
  70 struct scope6_id *
  71 scope6_ifattach(struct ifnet *ifp)
  72 {
  73         struct scope6_id *sid;
  74
  75         sid = (struct scope6_id *)kmalloc(sizeof(*sid), M_IFADDR,
  76             M_WAITOK | M_ZERO);
  77
  78         crit_enter();
  79
  80         /*
  81          * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard.
  82          * Should we rather hardcode here?
  83          */
  84         sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index;
  85         sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index;
  86 #ifdef MULTI_SCOPE
  87         /* by default, we don't care about scope boundary for these scopes. */
  88         sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1;
  89         sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1;
  90 #endif
  91
  92         crit_exit();
  93         return sid;
  94 }
  95
  96 void
  97 scope6_ifdetach(struct scope6_id *sid)
  98 {
  99         kfree(sid, M_IFADDR);
 100 }
 101
 102 int
 103 scope6_set(struct ifnet *ifp, struct scope6_id *idlist)
 104 {
 105         int i;
 106         int error = 0;
 107         struct scope6_id *sid = SID(ifp);
 108
 109         if (!sid)       /* paranoid? */
 110                 return (EINVAL);
 111
 112         /*
 113          * XXX: We need more consistency checks of the relationship among
 114          * scopes (e.g. an organization should be larger than a site).
 115          */
 116
 117         /*
 118          * TODO(XXX): after setting, we should reflect the changes to
 119          * interface addresses, routing table entries, PCB entries...
 120          */
 121
 122         crit_enter();
 123
 124         for (i = 0; i < 16; i++) {
 125                 if (idlist->s6id_list[i] &&
 126                     idlist->s6id_list[i] != sid->s6id_list[i]) {
 127                         /*
 128                          * An interface zone ID must be the corresponding
 129                          * interface index by definition.
 130                          */
 131                         if (i == IPV6_ADDR_SCOPE_INTFACELOCAL &&
 132                             idlist->s6id_list[i] != ifp->if_index) {
 133                                 crit_exit();
 134                                 return (EINVAL);
 135                         }
 136
 137                         if (i == IPV6_ADDR_SCOPE_LINKLOCAL &&
 138                             idlist->s6id_list[i] > if_index) {
 139                                 /*
 140                                  * XXX: theoretically, there should be no
 141                                  * relationship between link IDs and interface
 142                                  * IDs, but we check the consistency for
 143                                  * safety in later use.
 144                                  */
 145                                 crit_exit();
 146                                 return (EINVAL);
 147                         }
 148
 149                         /*
 150                          * XXX: we must need lots of work in this case,
 151                          * but we simply set the new value in this initial
 152                          * implementation.
 153                          */
 154                         sid->s6id_list[i] = idlist->s6id_list[i];
 155                 }
 156         }
 157         crit_exit();
 158
 159         return (error);
 160 }
 161
 162 int
 163 scope6_get(struct ifnet *ifp, struct scope6_id *idlist)
 164 {
 165         struct scope6_id *sid = SID(ifp);
 166
 167         if (sid == NULL)        /* paranoid? */
 168                 return (EINVAL);
 169
 170         *idlist = *sid;
 171
 172         return (0);
 173 }
 174
 175
 176 /*
 177  * Get a scope of the address. Node-local, link-local, site-local or global.
 178  */
 179 int
 180 in6_addrscope(struct in6_addr *addr)
 181 {
 182         int scope;
 183
 184         if (addr->s6_addr[0] == 0xfe) {
 185                 scope = addr->s6_addr[1] & 0xc0;
 186
 187                 switch (scope) {
 188                 case 0x80:
 189                         return IPV6_ADDR_SCOPE_LINKLOCAL;
 190                         break;
 191                 case 0xc0:
 192                         return IPV6_ADDR_SCOPE_SITELOCAL;
 193                         break;
 194                 default:
 195                         return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */
 196                         break;
 197                 }
 198         }
 199
 200
 201         if (addr->s6_addr[0] == 0xff) {
 202                 scope = addr->s6_addr[1] & 0x0f;
 203
 204                 /*
 205                  * due to other scope such as reserved,
 206                  * return scope doesn't work.
 207                  */
 208                 switch (scope) {
 209                 case IPV6_ADDR_SCOPE_INTFACELOCAL:
 210                         return IPV6_ADDR_SCOPE_INTFACELOCAL;
 211                         break;
 212                 case IPV6_ADDR_SCOPE_LINKLOCAL:
 213                         return IPV6_ADDR_SCOPE_LINKLOCAL;
 214                         break;
 215                 case IPV6_ADDR_SCOPE_SITELOCAL:
 216                         return IPV6_ADDR_SCOPE_SITELOCAL;
 217                         break;
 218                 default:
 219                         return IPV6_ADDR_SCOPE_GLOBAL;
 220                         break;
 221                 }
 222         }
 223
 224         /*
 225          * Regard loopback and unspecified addresses as global, since
 226          * they have no ambiguity.
 227          */
 228         if (bcmp(&kin6addr_loopback, addr, sizeof(*addr) - 1) == 0) {
 229                 if (addr->s6_addr[15] == 1) /* loopback */
 230                         return IPV6_ADDR_SCOPE_LINKLOCAL;
 231                 if (addr->s6_addr[15] == 0) /* unspecified */
 232                         return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */
 233         }
 234
 235         return IPV6_ADDR_SCOPE_GLOBAL;
 236 }
 237
 238 /*
 239  * When we introduce the "4+28" split semantics in sin6_scope_id,
 240  * a 32bit integer is not enough to tell a large ID from an error (-1).
 241  * So, we intentionally use a large type as the return value.
 242  */
 243 int
 244 in6_addr2zoneid(struct ifnet *ifp,      /* must not be NULL */
 245                 struct in6_addr *addr,  /* must not be NULL */
 246                 u_int32_t *ret_id)      /* must not be NULL */
 247 {
 248         int scope;
 249         u_int32_t zoneid = 0;
 250         struct scope6_id *sid = SID(ifp);
 251
 252 #ifdef DIAGNOSTIC
 253         if (sid == NULL) { /* should not happen */
 254                 panic("in6_addr2zoneid: scope array is NULL");
 255                 /* NOTREACHED */
 256         }
 257         if (ret_id == NULL) {
 258                 panic("in6_addr2zoneid: return ID is null");
 259                 /* NOTREACHED */
 260         }
 261 #endif
 262
 263         /*
 264          * special case: the loopback address can only belong to a loopback
 265          * interface.
 266          */
 267         if (IN6_IS_ADDR_LOOPBACK(addr)) {
 268                 if (!(ifp->if_flags & IFF_LOOPBACK)) {
 269                         return (-1);
 270                 } else {
 271                         *ret_id = 0; /* there's no ambiguity */
 272                         return (0);
 273                 }
 274         }
 275
 276         scope = in6_addrscope(addr);
 277
 278         switch (scope) {
 279         case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */
 280                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL];
 281                 break;
 282
 283         case IPV6_ADDR_SCOPE_LINKLOCAL:
 284                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL];
 285                 break;
 286
 287         case IPV6_ADDR_SCOPE_SITELOCAL:
 288                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL];
 289                 break;
 290
 291         case IPV6_ADDR_SCOPE_ORGLOCAL:
 292                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL];
 293                 break;
 294
 295         default:
 296                 zoneid = 0;     /* XXX: treat as global. */
 297                 break;
 298         }
 299         *ret_id = zoneid;
 300         return (0);
 301 }
 302
 303 void
 304 scope6_setdefault(struct ifnet *ifp)    /* note that this might be NULL */
 305 {
 306         /*
 307          * Currently, this function just set the default "interfaces"
 308          * and "links" according to the given interface.
 309          * We might eventually have to separate the notion of "link" from
 310          * "interface" and provide a user interface to set the default.
 311          */
 312         if (ifp) {
 313                 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] =
 314                         ifp->if_index;
 315                 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] =
 316                         ifp->if_index;
 317         } else {
 318                 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0;
 319                 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0;
 320         }
 321 }
 322
 323 int
 324 scope6_get_default(struct scope6_id *idlist)
 325 {
 326         *idlist = sid_default;
 327
 328         return (0);
 329 }
 330
 331 u_int32_t
 332 scope6_addr2default(struct in6_addr *addr)
 333 {
 334         /*
 335          * special case: The loopback address should be considered as
 336          * link-local, but there's no ambiguity in the syntax.
 337          */
 338         if (IN6_IS_ADDR_LOOPBACK(addr))
 339                 return (0);
 340
 341         return (sid_default.s6id_list[in6_addrscope(addr)]);
 342 }
 343
 344 /*
 345  * Determine the appropriate scope zone ID for in6 and ifp.  If ret_id is
 346  * non NULL, it is set to the zone ID.  If the zone ID needs to be embedded
 347   * in the in6_addr structure, in6 will be modified.
 348  */
 349 int
 350 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id)
 351 {
 352         int scope;
 353         u_int32_t zoneid = 0;
 354         struct scope6_id *sid;
 355
 356         ifnet_serialize_all(ifp);
 357
 358         sid = SID(ifp);
 359
 360 #ifdef DIAGNOSTIC
 361         if (sid == NULL) { /* should not happen */
 362                 panic("in6_setscope: scope array is NULL");
 363                 /* NOTREACHED */
 364         }
 365 #endif
 366
 367         /*
 368          * special case: the loopback address can only belong to a loopback
 369          * interface.
 370          */
 371         if (IN6_IS_ADDR_LOOPBACK(in6)) {
 372                 if (!(ifp->if_flags & IFF_LOOPBACK)) {
 373                         ifnet_deserialize_all(ifp);
 374                         return (EINVAL);
 375                 } else {
 376                         if (ret_id != NULL)
 377                                 *ret_id = 0; /* there's no ambiguity */
 378                         ifnet_deserialize_all(ifp);
 379                         return (0);
 380                 }
 381         }
 382
 383         scope = in6_addrscope(in6);
 384
 385         switch (scope) {
 386         case IPV6_ADDR_SCOPE_NODELOCAL: /* should be interface index */
 387                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_NODELOCAL];
 388                 break;
 389
 390         case IPV6_ADDR_SCOPE_LINKLOCAL:
 391                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL];
 392                 break;
 393
 394         case IPV6_ADDR_SCOPE_SITELOCAL:
 395                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL];
 396                 break;
 397
 398         case IPV6_ADDR_SCOPE_ORGLOCAL:
 399                 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL];
 400                 break;
 401
 402         default:
 403                 zoneid = 0;     /* XXX: treat as global. */
 404                 break;
 405         }
 406
 407         ifnet_deserialize_all(ifp);
 408
 409         if (ret_id != NULL)
 410                 *ret_id = zoneid;
 411
 412         if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_NODELOCAL(in6) )
 413                 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */
 414
 415         return (0);
 416 }