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 } __attribute__ ((packed));
  53
  54
  55 /* length is the number of valuable bits of prefix structure
  56 * 18 bytes is current length in structure, if address is ipv4
  57 * 30 bytes is in case of ipv6
  58 */
  59 #define PREFIX_LEN_ROUTE_TYPE_5_IPV4 (18*8)
  60 #define PREFIX_LEN_ROUTE_TYPE_5_IPV6 (30*8)
  61
  62 /* EVPN address (RFC 7432) */
  63 struct evpn_addr
  64 {
  65   u_char route_type;
  66   u_char flags;
  67 #define IP_ADDR_NONE      0x0
  68 #define IP_ADDR_V4        0x1
  69 #define IP_ADDR_V6        0x2
  70 #define IP_PREFIX_V4      0x4
  71 #define IP_PREFIX_V6      0x8
  72   struct ethaddr mac;
  73   uint32_t eth_tag;
  74   u_char ip_prefix_length;
  75   union
  76   {
  77     u_char addr;
  78     struct in_addr v4_addr;
  79     struct in6_addr v6_addr;
  80   } ip;
  81 };
  82
  83 /* EVPN prefix structure. */
  84 struct prefix_evpn
  85 {
  86   u_char family;
  87   u_char prefixlen;
  88   struct evpn_addr prefix __attribute__ ((aligned (8)));
  89 };
  90
  91 /*
  92  * A struct prefix contains an address family, a prefix length, and an
  93  * address.  This can represent either a 'network prefix' as defined
  94  * by CIDR, where the 'host bits' of the prefix are 0
  95  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
  96  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
  97  * interface.
  98  */
  99
 100 /* different OSes use different names */
 101 #if defined(AF_PACKET)
 102 #define AF_ETHERNET AF_PACKET
 103 #else
 104 #if defined(AF_LINK)
 105 #define AF_ETHERNET AF_LINK
 106 #endif
 107 #endif
 108
 109 /* IPv4 and IPv6 unified prefix structure. */
 110 struct prefix
 111 {
 112   u_char family;
 113   u_char prefixlen;
 114   union
 115   {
 116     u_char prefix;
 117     struct in_addr prefix4;
 118     struct in6_addr prefix6;
 119     struct
 120     {
 121       struct in_addr id;
 122       struct in_addr adv_router;
 123     } lp;
 124     struct ethaddr prefix_eth;  /* AF_ETHERNET */
 125     u_char val[8];
 126     uintptr_t ptr;
 127     struct evpn_addr prefix_evpn;
 128   } u __attribute__ ((aligned (8)));
 129 };
 130
 131 /* IPv4 prefix structure. */
 132 struct prefix_ipv4
 133 {
 134   u_char family;
 135   u_char prefixlen;
 136   struct in_addr prefix __attribute__ ((aligned (8)));
 137 };
 138
 139 /* IPv6 prefix structure. */
 140 struct prefix_ipv6
 141 {
 142   u_char family;
 143   u_char prefixlen;
 144   struct in6_addr prefix __attribute__ ((aligned (8)));
 145 };
 146
 147 struct prefix_ls
 148 {
 149   u_char family;
 150   u_char prefixlen;
 151   struct in_addr id __attribute__ ((aligned (8)));
 152   struct in_addr adv_router;
 153 };
 154
 155 /* Prefix for routing distinguisher. */
 156 struct prefix_rd
 157 {
 158   u_char family;
 159   u_char prefixlen;
 160   u_char val[8] __attribute__ ((aligned (8)));
 161 };
 162
 163 /* Prefix for ethernet. */
 164 struct prefix_eth
 165 {
 166   u_char family;
 167   u_char prefixlen;
 168   struct ethaddr eth_addr __attribute__ ((aligned (8))); /* AF_ETHERNET */
 169 };
 170
 171 /* Prefix for a generic pointer */
 172 struct prefix_ptr
 173 {
 174   u_char family;
 175   u_char prefixlen;
 176   uintptr_t prefix __attribute__ ((aligned (8)));
 177 };
 178
 179 struct prefix_sg
 180 {
 181   u_char family;
 182   u_char prefixlen;
 183   struct in_addr src __attribute ((aligned (8)));
 184   struct in_addr grp;
 185 };
 186
 187 /* helper to get type safety/avoid casts on calls
 188  * (w/o this, functions accepting all prefix types need casts on the caller
 189  * side, which strips type safety since the cast will accept any pointer
 190  * type.)
 191  */
 192 union prefixptr
 193 {
 194   struct prefix *p;
 195   struct prefix_ipv4 *p4;
 196   struct prefix_ipv6 *p6;
 197   struct prefix_evpn *evp;
 198 } __attribute__ ((transparent_union));
 199
 200 union prefixconstptr
 201 {
 202   const struct prefix *p;
 203   const struct prefix_ipv4 *p4;
 204   const struct prefix_ipv6 *p6;
 205   const struct prefix_evpn *evp;
 206 } __attribute__ ((transparent_union));
 207
 208 #ifndef INET_ADDRSTRLEN
 209 #define INET_ADDRSTRLEN 16
 210 #endif /* INET_ADDRSTRLEN */
 211
 212 #ifndef INET6_ADDRSTRLEN
 213 #define INET6_ADDRSTRLEN 46
 214 #endif /* INET6_ADDRSTRLEN */
 215
 216 #ifndef INET6_BUFSIZ
 217 #define INET6_BUFSIZ 51
 218 #endif /* INET6_BUFSIZ */
 219
 220 /* Maximum prefix string length (IPv6) */
 221 #define PREFIX_STRLEN 51
 222
 223 /* Max bit/byte length of IPv4 address. */
 224 #define IPV4_MAX_BYTELEN    4
 225 #define IPV4_MAX_BITLEN    32
 226 #define IPV4_MAX_PREFIXLEN 32
 227 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 228 #define IPV4_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV4_MAX_BYTELEN) == 0)
 229 #define IPV4_ADDR_COPY(D,S)  memcpy ((D), (S), IPV4_MAX_BYTELEN)
 230
 231 #define IPV4_NET0(a)    ((((u_int32_t) (a)) & 0xff000000) == 0x00000000)
 232 #define IPV4_NET127(a)  ((((u_int32_t) (a)) & 0xff000000) == 0x7f000000)
 233 #define IPV4_LINKLOCAL(a) ((((u_int32_t) (a)) & 0xffff0000) == 0xa9fe0000)
 234 #define IPV4_CLASS_DE(a)  ((((u_int32_t) (a)) & 0xe0000000) == 0xe0000000)
 235
 236 /* Max bit/byte length of IPv6 address. */
 237 #define IPV6_MAX_BYTELEN    16
 238 #define IPV6_MAX_BITLEN    128
 239 #define IPV6_MAX_PREFIXLEN 128
 240 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 241 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 242 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 243
 244 /* Count prefix size from mask length */
 245 #define PSIZE(a) (((a) + 7) / (8))
 246
 247 #define BSIZE(a) ((a) * (8))
 248
 249 /* Prefix's family member. */
 250 #define PREFIX_FAMILY(p)  ((p)->family)
 251
 252 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 253 #ifndef s6_addr32
 254 #if defined(SUNOS_5)
 255 /* Some SunOS define s6_addr32 only to kernel */
 256 #define s6_addr32 _S6_un._S6_u32
 257 #else
 258 #define s6_addr32 __u6_addr.__u6_addr32
 259 #endif /* SUNOS_5 */
 260 #endif /*s6_addr32*/
 261
 262 /* Prototypes. */
 263 extern int str2family(const char *);
 264 extern int afi2family (afi_t);
 265 extern afi_t family2afi (int);
 266 extern const char *safi2str(safi_t safi);
 267 extern const char *afi2str(afi_t afi);
 268
 269 /* Check bit of the prefix. */
 270 extern unsigned int prefix_bit (const u_char *prefix, const u_char prefixlen);
 271 extern unsigned int prefix6_bit (const struct in6_addr *prefix, const u_char prefixlen);
 272
 273 extern struct prefix *prefix_new (void);
 274 extern void prefix_free (struct prefix *);
 275 extern const char *prefix_family_str (const struct prefix *);
 276 extern int prefix_blen (const struct prefix *);
 277 extern int str2prefix (const char *, struct prefix *);
 278
 279 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 280
 281 extern const char *prefix2str (union prefixconstptr, char *, int);
 282 extern int prefix_match (const struct prefix *, const struct prefix *);
 283 extern int prefix_same (const struct prefix *, const struct prefix *);
 284 extern int prefix_cmp (const struct prefix *, const struct prefix *);
 285 extern int prefix_common_bits (const struct prefix *, const struct prefix *);
 286 extern void prefix_copy (struct prefix *dest, const struct prefix *src);
 287 extern void apply_mask (struct prefix *);
 288
 289 extern struct prefix *sockunion2prefix (const union sockunion *dest,
 290                                         const union sockunion *mask);
 291 extern struct prefix *sockunion2hostprefix (const union sockunion *, struct prefix *p);
 292 extern void prefix2sockunion (const struct prefix *, union sockunion *);
 293
 294 extern int str2prefix_eth (const char *, struct prefix_eth *);
 295
 296 extern struct prefix_ipv4 *prefix_ipv4_new (void);
 297 extern void prefix_ipv4_free (struct prefix_ipv4 *);
 298 extern int str2prefix_ipv4 (const char *, struct prefix_ipv4 *);
 299 extern void apply_mask_ipv4 (struct prefix_ipv4 *);
 300
 301 #define PREFIX_COPY_IPV4(DST, SRC)      \
 302         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 303
 304 extern int prefix_ipv4_any (const struct prefix_ipv4 *);
 305 extern void apply_classful_mask_ipv4 (struct prefix_ipv4 *);
 306
 307 extern u_char ip_masklen (struct in_addr);
 308 extern void masklen2ip (const int, struct in_addr *);
 309 /* returns the network portion of the host address */
 310 extern in_addr_t ipv4_network_addr (in_addr_t hostaddr, int masklen);
 311 /* given the address of a host on a network and the network mask length,
 312  * calculate the broadcast address for that network;
 313  * special treatment for /31: returns the address of the other host
 314  * on the network by flipping the host bit */
 315 extern in_addr_t ipv4_broadcast_addr (in_addr_t hostaddr, int masklen);
 316
 317 extern int netmask_str2prefix_str (const char *, const char *, char *);
 318
 319 extern struct prefix_ipv6 *prefix_ipv6_new (void);
 320 extern void prefix_ipv6_free (struct prefix_ipv6 *);
 321 extern int str2prefix_ipv6 (const char *, struct prefix_ipv6 *);
 322 extern void apply_mask_ipv6 (struct prefix_ipv6 *);
 323
 324 #define PREFIX_COPY_IPV6(DST, SRC)      \
 325         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 326
 327 extern int ip6_masklen (struct in6_addr);
 328 extern void masklen2ip6 (const int, struct in6_addr *);
 329
 330 extern const char *inet6_ntoa (struct in6_addr);
 331
 332 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 333 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 334
 335 static inline int ipv6_martian (struct in6_addr *addr)
 336 {
 337   struct in6_addr localhost_addr;
 338
 339   inet_pton (AF_INET6, "::1", &localhost_addr);
 340
 341   if (IPV6_ADDR_SAME(&localhost_addr, addr))
 342     return 1;
 343
 344   return 0;
 345 }
 346
 347 extern int all_digit (const char *);
 348
 349 /* NOTE: This routine expects the address argument in network byte order. */
 350 static inline int ipv4_martian (struct in_addr *addr)
 351 {
 352   in_addr_t ip = ntohl(addr->s_addr);
 353
 354   if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 355     return 1;
 356   }
 357   return 0;
 358 }
 359
 360 static inline int
 361 is_default_prefix (struct prefix *p)
 362 {
 363   if (!p)
 364     return 0;
 365
 366   if (((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY))
 367       || ((p->family == AF_INET6) &&
 368           !memcmp(&p->u.prefix6, &in6addr_any, sizeof (struct in6_addr))))
 369     return 1;
 370
 371   return 0;
 372 }
 373
 374 #endif /* _ZEBRA_PREFIX_H */