lib/prefix.h

   1 /*
   2  * Prefix structure.
   3  * Copyright (C) 1998 Kunihiro Ishiguro
   4  *
   5  * This file is part of GNU Zebra.
   6  *
   7  * GNU Zebra is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * GNU Zebra is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with GNU Zebra; see the file COPYING.  If not, write to the Free
  19  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20  * 02111-1307, USA.
  21  */
  22
  23 #ifndef _ZEBRA_PREFIX_H
  24 #define _ZEBRA_PREFIX_H
  25
  26 #ifdef SUNOS_5
  27 # include <sys/ethernet.h>
  28 #else
  29 # ifdef GNU_LINUX
  30 #  include <net/ethernet.h>
  31 # else
  32 #  include <netinet/if_ether.h>
  33 # endif
  34 #endif
  35 #include "sockunion.h"
  36
  37 #ifndef ETHER_ADDR_LEN
  38 #ifdef ETHERADDRL
  39 #define ETHER_ADDR_LEN  ETHERADDRL
  40 #else
  41 #define ETHER_ADDR_LEN 6
  42 #endif
  43 #endif
  44
  45 #define ETHER_ADDR_STRLEN (3*ETHER_ADDR_LEN)
  46 /*
  47  * there isn't a portable ethernet address type. We define our
  48  * own to simplify internal handling
  49  */
  50 struct ethaddr {
  51     u_char octet[ETHER_ADDR_LEN];
  52 } __packed;
  53
  54
  55 /*
  56  * A struct prefix contains an address family, a prefix length, and an
  57  * address.  This can represent either a 'network prefix' as defined
  58  * by CIDR, where the 'host bits' of the prefix are 0
  59  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
  60  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
  61  * interface.
  62  */
  63
  64 /* different OSes use different names */
  65 #if defined(AF_PACKET)
  66 #define AF_ETHERNET AF_PACKET
  67 #else
  68 #if defined(AF_LINK)
  69 #define AF_ETHERNET AF_LINK
  70 #endif
  71 #endif
  72
  73 /* IPv4 and IPv6 unified prefix structure. */
  74 struct prefix
  75 {
  76   u_char family;
  77   u_char prefixlen;
  78   union
  79   {
  80     u_char prefix;
  81     struct in_addr prefix4;
  82     struct in6_addr prefix6;
  83     struct
  84     {
  85       struct in_addr id;
  86       struct in_addr adv_router;
  87     } lp;
  88     struct ethaddr prefix_eth;  /* AF_ETHERNET */
  89     u_char val[8];
  90     uintptr_t ptr;
  91   } u __attribute__ ((aligned (8)));
  92 };
  93
  94 /* IPv4 prefix structure. */
  95 struct prefix_ipv4
  96 {
  97   u_char family;
  98   u_char prefixlen;
  99   struct in_addr prefix __attribute__ ((aligned (8)));
 100 };
 101
 102 /* IPv6 prefix structure. */
 103 struct prefix_ipv6
 104 {
 105   u_char family;
 106   u_char prefixlen;
 107   struct in6_addr prefix __attribute__ ((aligned (8)));
 108 };
 109
 110 struct prefix_ls
 111 {
 112   u_char family;
 113   u_char prefixlen;
 114   struct in_addr id __attribute__ ((aligned (8)));
 115   struct in_addr adv_router;
 116 };
 117
 118 /* Prefix for routing distinguisher. */
 119 struct prefix_rd
 120 {
 121   u_char family;
 122   u_char prefixlen;
 123   u_char val[8] __attribute__ ((aligned (8)));
 124 };
 125
 126 /* Prefix for ethernet. */
 127 struct prefix_eth
 128 {
 129   u_char family;
 130   u_char prefixlen;
 131   struct ethaddr eth_addr __attribute__ ((aligned (8))); /* AF_ETHERNET */
 132 };
 133
 134 /* Prefix for a generic pointer */
 135 struct prefix_ptr
 136 {
 137   u_char family;
 138   u_char prefixlen;
 139   uintptr_t prefix __attribute__ ((aligned (8)));
 140 };
 141
 142 struct prefix_sg
 143 {
 144   u_char family;
 145   u_char prefixlen;
 146   struct in_addr src __attribute ((aligned (8)));
 147   struct in_addr grp;
 148 };
 149
 150 /* helper to get type safety/avoid casts on calls
 151  * (w/o this, functions accepting all prefix types need casts on the caller
 152  * side, which strips type safety since the cast will accept any pointer
 153  * type.)
 154  */
 155 union prefix46ptr
 156 {
 157   struct prefix *p;
 158   struct prefix_ipv4 *p4;
 159   struct prefix_ipv6 *p6;
 160 } __attribute__ ((transparent_union));
 161
 162 union prefix46constptr
 163 {
 164   const struct prefix *p;
 165   const struct prefix_ipv4 *p4;
 166   const struct prefix_ipv6 *p6;
 167 } __attribute__ ((transparent_union));
 168
 169 #ifndef INET_ADDRSTRLEN
 170 #define INET_ADDRSTRLEN 16
 171 #endif /* INET_ADDRSTRLEN */
 172
 173 #ifndef INET6_ADDRSTRLEN
 174 #define INET6_ADDRSTRLEN 46
 175 #endif /* INET6_ADDRSTRLEN */
 176
 177 #ifndef INET6_BUFSIZ
 178 #define INET6_BUFSIZ 51
 179 #endif /* INET6_BUFSIZ */
 180
 181 /* Maximum prefix string length (IPv6) */
 182 #define PREFIX_STRLEN 51
 183
 184 /* Max bit/byte length of IPv4 address. */
 185 #define IPV4_MAX_BYTELEN    4
 186 #define IPV4_MAX_BITLEN    32
 187 #define IPV4_MAX_PREFIXLEN 32
 188 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 189 #define IPV4_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV4_MAX_BYTELEN) == 0)
 190 #define IPV4_ADDR_COPY(D,S)  memcpy ((D), (S), IPV4_MAX_BYTELEN)
 191
 192 #define IPV4_NET0(a)    ((((u_int32_t) (a)) & 0xff000000) == 0x00000000)
 193 #define IPV4_NET127(a)  ((((u_int32_t) (a)) & 0xff000000) == 0x7f000000)
 194 #define IPV4_LINKLOCAL(a) ((((u_int32_t) (a)) & 0xffff0000) == 0xa9fe0000)
 195 #define IPV4_CLASS_DE(a)  ((((u_int32_t) (a)) & 0xe0000000) == 0xe0000000)
 196
 197 /* Max bit/byte length of IPv6 address. */
 198 #define IPV6_MAX_BYTELEN    16
 199 #define IPV6_MAX_BITLEN    128
 200 #define IPV6_MAX_PREFIXLEN 128
 201 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 202 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 203 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 204
 205 /* Count prefix size from mask length */
 206 #define PSIZE(a) (((a) + 7) / (8))
 207
 208 /* Prefix's family member. */
 209 #define PREFIX_FAMILY(p)  ((p)->family)
 210
 211 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 212 #ifndef s6_addr32
 213 #if defined(SUNOS_5)
 214 /* Some SunOS define s6_addr32 only to kernel */
 215 #define s6_addr32 _S6_un._S6_u32
 216 #else
 217 #define s6_addr32 __u6_addr.__u6_addr32
 218 #endif /* SUNOS_5 */
 219 #endif /*s6_addr32*/
 220
 221 /* Prototypes. */
 222 extern int str2family(const char *);
 223 extern int afi2family (afi_t);
 224 extern afi_t family2afi (int);
 225 extern const char *safi2str(safi_t safi);
 226 extern const char *afi2str(afi_t afi);
 227
 228 /* Check bit of the prefix. */
 229 extern unsigned int prefix_bit (const u_char *prefix, const u_char prefixlen);
 230 extern unsigned int prefix6_bit (const struct in6_addr *prefix, const u_char prefixlen);
 231
 232 extern struct prefix *prefix_new (void);
 233 extern void prefix_free (struct prefix *);
 234 extern const char *prefix_family_str (const struct prefix *);
 235 extern int prefix_blen (const struct prefix *);
 236 extern int str2prefix (const char *, struct prefix *);
 237
 238 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 239
 240 extern const char *prefix2str (union prefix46constptr, char *, int);
 241 extern int prefix_match (const struct prefix *, const struct prefix *);
 242 extern int prefix_same (const struct prefix *, const struct prefix *);
 243 extern int prefix_cmp (const struct prefix *, const struct prefix *);
 244 extern int prefix_common_bits (const struct prefix *, const struct prefix *);
 245 extern void prefix_copy (struct prefix *dest, const struct prefix *src);
 246 extern void apply_mask (struct prefix *);
 247
 248 extern struct prefix *sockunion2prefix (const union sockunion *dest,
 249                                         const union sockunion *mask);
 250 extern struct prefix *sockunion2hostprefix (const union sockunion *, struct prefix *p);
 251 extern void prefix2sockunion (const struct prefix *, union sockunion *);
 252
 253 extern int str2prefix_eth (const char *, struct prefix_eth *);
 254
 255 extern struct prefix_ipv4 *prefix_ipv4_new (void);
 256 extern void prefix_ipv4_free (struct prefix_ipv4 *);
 257 extern int str2prefix_ipv4 (const char *, struct prefix_ipv4 *);
 258 extern void apply_mask_ipv4 (struct prefix_ipv4 *);
 259
 260 #define PREFIX_COPY_IPV4(DST, SRC)      \
 261         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 262
 263 extern int prefix_ipv4_any (const struct prefix_ipv4 *);
 264 extern void apply_classful_mask_ipv4 (struct prefix_ipv4 *);
 265
 266 extern u_char ip_masklen (struct in_addr);
 267 extern void masklen2ip (const int, struct in_addr *);
 268 /* returns the network portion of the host address */
 269 extern in_addr_t ipv4_network_addr (in_addr_t hostaddr, int masklen);
 270 /* given the address of a host on a network and the network mask length,
 271  * calculate the broadcast address for that network;
 272  * special treatment for /31: returns the address of the other host
 273  * on the network by flipping the host bit */
 274 extern in_addr_t ipv4_broadcast_addr (in_addr_t hostaddr, int masklen);
 275
 276 extern int netmask_str2prefix_str (const char *, const char *, char *);
 277
 278 extern struct prefix_ipv6 *prefix_ipv6_new (void);
 279 extern void prefix_ipv6_free (struct prefix_ipv6 *);
 280 extern int str2prefix_ipv6 (const char *, struct prefix_ipv6 *);
 281 extern void apply_mask_ipv6 (struct prefix_ipv6 *);
 282
 283 #define PREFIX_COPY_IPV6(DST, SRC)      \
 284         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 285
 286 extern int ip6_masklen (struct in6_addr);
 287 extern void masklen2ip6 (const int, struct in6_addr *);
 288
 289 extern const char *inet6_ntoa (struct in6_addr);
 290
 291 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 292 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 293
 294 static inline int ipv6_martian (struct in6_addr *addr)
 295 {
 296   struct in6_addr localhost_addr;
 297
 298   inet_pton (AF_INET6, "::1", &localhost_addr);
 299
 300   if (IPV6_ADDR_SAME(&localhost_addr, addr))
 301     return 1;
 302
 303   return 0;
 304 }
 305
 306 extern int all_digit (const char *);
 307
 308 /* NOTE: This routine expects the address argument in network byte order. */
 309 static inline int ipv4_martian (struct in_addr *addr)
 310 {
 311   in_addr_t ip = ntohl(addr->s_addr);
 312
 313   if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 314     return 1;
 315   }
 316   return 0;
 317 }
 318
 319 static inline int
 320 is_default_prefix (struct prefix *p)
 321 {
 322   if (!p)
 323     return 0;
 324
 325   if (((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY))
 326       || ((p->family == AF_INET6) &&
 327           !memcmp(&p->u.prefix6, &in6addr_any, sizeof (struct in6_addr))))
 328     return 1;
 329
 330   return 0;
 331 }
 332
 333 #endif /* _ZEBRA_PREFIX_H */