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 along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef _ZEBRA_PREFIX_H
  23 #define _ZEBRA_PREFIX_H
  24
  25 #ifdef SUNOS_5
  26 # include <sys/ethernet.h>
  27 #else
  28 # ifdef GNU_LINUX
  29 #  include <net/ethernet.h>
  30 # else
  31 #  include <netinet/if_ether.h>
  32 # endif
  33 #endif
  34 #include "sockunion.h"
  35
  36 #ifndef ETHER_ADDR_LEN
  37 #ifdef ETHERADDRL
  38 #define ETHER_ADDR_LEN  ETHERADDRL
  39 #else
  40 #define ETHER_ADDR_LEN 6
  41 #endif
  42 #endif
  43
  44 #define ETHER_ADDR_STRLEN (3*ETHER_ADDR_LEN)
  45 /*
  46  * there isn't a portable ethernet address type. We define our
  47  * own to simplify internal handling
  48  */
  49 struct ethaddr {
  50     u_char octet[ETHER_ADDR_LEN];
  51 } __attribute__ ((packed));
  52
  53
  54 /* length is the number of valuable bits of prefix structure
  55 * 18 bytes is current length in structure, if address is ipv4
  56 * 30 bytes is in case of ipv6
  57 */
  58 #define PREFIX_LEN_ROUTE_TYPE_5_IPV4 (18*8)
  59 #define PREFIX_LEN_ROUTE_TYPE_5_IPV6 (30*8)
  60
  61 /* EVPN address (RFC 7432) */
  62 struct evpn_addr
  63 {
  64   u_char route_type;
  65   u_char flags;
  66 #define IP_ADDR_NONE      0x0
  67 #define IP_ADDR_V4        0x1
  68 #define IP_ADDR_V6        0x2
  69 #define IP_PREFIX_V4      0x4
  70 #define IP_PREFIX_V6      0x8
  71   struct ethaddr mac;
  72   uint32_t eth_tag;
  73   u_char ip_prefix_length;
  74   union
  75   {
  76     u_char addr;
  77     struct in_addr v4_addr;
  78     struct in6_addr v6_addr;
  79   } ip;
  80 };
  81
  82 /* EVPN prefix structure. */
  83 struct prefix_evpn
  84 {
  85   u_char family;
  86   u_char prefixlen;
  87   struct evpn_addr prefix __attribute__ ((aligned (8)));
  88 };
  89
  90 /*
  91  * A struct prefix contains an address family, a prefix length, and an
  92  * address.  This can represent either a 'network prefix' as defined
  93  * by CIDR, where the 'host bits' of the prefix are 0
  94  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
  95  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
  96  * interface.
  97  */
  98
  99 /* different OSes use different names */
 100 #if defined(AF_PACKET)
 101 #define AF_ETHERNET AF_PACKET
 102 #else
 103 #if defined(AF_LINK)
 104 #define AF_ETHERNET AF_LINK
 105 #endif
 106 #endif
 107
 108 /* IPv4 and IPv6 unified prefix structure. */
 109 struct prefix
 110 {
 111   u_char family;
 112   u_char prefixlen;
 113   union
 114   {
 115     u_char prefix;
 116     struct in_addr prefix4;
 117     struct in6_addr prefix6;
 118     struct
 119     {
 120       struct in_addr id;
 121       struct in_addr adv_router;
 122     } lp;
 123     struct ethaddr prefix_eth;  /* AF_ETHERNET */
 124     u_char val[8];
 125     uintptr_t ptr;
 126     struct evpn_addr prefix_evpn;
 127   } u __attribute__ ((aligned (8)));
 128 };
 129
 130 /* IPv4 prefix structure. */
 131 struct prefix_ipv4
 132 {
 133   u_char family;
 134   u_char prefixlen;
 135   struct in_addr prefix __attribute__ ((aligned (8)));
 136 };
 137
 138 /* IPv6 prefix structure. */
 139 struct prefix_ipv6
 140 {
 141   u_char family;
 142   u_char prefixlen;
 143   struct in6_addr prefix __attribute__ ((aligned (8)));
 144 };
 145
 146 struct prefix_ls
 147 {
 148   u_char family;
 149   u_char prefixlen;
 150   struct in_addr id __attribute__ ((aligned (8)));
 151   struct in_addr adv_router;
 152 };
 153
 154 /* Prefix for routing distinguisher. */
 155 struct prefix_rd
 156 {
 157   u_char family;
 158   u_char prefixlen;
 159   u_char val[8] __attribute__ ((aligned (8)));
 160 };
 161
 162 /* Prefix for ethernet. */
 163 struct prefix_eth
 164 {
 165   u_char family;
 166   u_char prefixlen;
 167   struct ethaddr eth_addr __attribute__ ((aligned (8))); /* AF_ETHERNET */
 168 };
 169
 170 /* Prefix for a generic pointer */
 171 struct prefix_ptr
 172 {
 173   u_char family;
 174   u_char prefixlen;
 175   uintptr_t prefix __attribute__ ((aligned (8)));
 176 };
 177
 178 struct prefix_sg
 179 {
 180   u_char family;
 181   u_char prefixlen;
 182   struct in_addr src __attribute__ ((aligned (8)));
 183   struct in_addr grp;
 184 };
 185
 186 /* helper to get type safety/avoid casts on calls
 187  * (w/o this, functions accepting all prefix types need casts on the caller
 188  * side, which strips type safety since the cast will accept any pointer
 189  * type.)
 190  */
 191 union prefixptr
 192 {
 193   struct prefix *p;
 194   struct prefix_ipv4 *p4;
 195   struct prefix_ipv6 *p6;
 196   struct prefix_evpn *evp;
 197 } __attribute__ ((transparent_union));
 198
 199 union prefixconstptr
 200 {
 201   const struct prefix *p;
 202   const struct prefix_ipv4 *p4;
 203   const struct prefix_ipv6 *p6;
 204   const struct prefix_evpn *evp;
 205 } __attribute__ ((transparent_union));
 206
 207 #ifndef INET_ADDRSTRLEN
 208 #define INET_ADDRSTRLEN 16
 209 #endif /* INET_ADDRSTRLEN */
 210
 211 #ifndef INET6_ADDRSTRLEN
 212 #define INET6_ADDRSTRLEN 46
 213 #endif /* INET6_ADDRSTRLEN */
 214
 215 #ifndef INET6_BUFSIZ
 216 #define INET6_BUFSIZ 51
 217 #endif /* INET6_BUFSIZ */
 218
 219 /* Maximum prefix string length (IPv6) */
 220 #define PREFIX_STRLEN 51
 221
 222 /* Max bit/byte length of IPv4 address. */
 223 #define IPV4_MAX_BYTELEN    4
 224 #define IPV4_MAX_BITLEN    32
 225 #define IPV4_MAX_PREFIXLEN 32
 226 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 227 #define IPV4_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV4_MAX_BYTELEN) == 0)
 228 #define IPV4_ADDR_COPY(D,S)  memcpy ((D), (S), IPV4_MAX_BYTELEN)
 229
 230 #define IPV4_NET0(a)    ((((u_int32_t) (a)) & 0xff000000) == 0x00000000)
 231 #define IPV4_NET127(a)  ((((u_int32_t) (a)) & 0xff000000) == 0x7f000000)
 232 #define IPV4_LINKLOCAL(a) ((((u_int32_t) (a)) & 0xffff0000) == 0xa9fe0000)
 233 #define IPV4_CLASS_DE(a)  ((((u_int32_t) (a)) & 0xe0000000) == 0xe0000000)
 234
 235 /* Max bit/byte length of IPv6 address. */
 236 #define IPV6_MAX_BYTELEN    16
 237 #define IPV6_MAX_BITLEN    128
 238 #define IPV6_MAX_PREFIXLEN 128
 239 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 240 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 241 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 242
 243 /* Count prefix size from mask length */
 244 #define PSIZE(a) (((a) + 7) / (8))
 245
 246 #define BSIZE(a) ((a) * (8))
 247
 248 /* Prefix's family member. */
 249 #define PREFIX_FAMILY(p)  ((p)->family)
 250
 251 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 252 #ifndef s6_addr32
 253 #if defined(SUNOS_5)
 254 /* Some SunOS define s6_addr32 only to kernel */
 255 #define s6_addr32 _S6_un._S6_u32
 256 #else
 257 #define s6_addr32 __u6_addr.__u6_addr32
 258 #endif /* SUNOS_5 */
 259 #endif /*s6_addr32*/
 260
 261 /* Prototypes. */
 262 extern int str2family(const char *);
 263 extern int afi2family (afi_t);
 264 extern afi_t family2afi (int);
 265 extern const char *safi2str(safi_t safi);
 266 extern const char *afi2str(afi_t afi);
 267
 268 /* Check bit of the prefix. */
 269 extern unsigned int prefix_bit (const u_char *prefix, const u_char prefixlen);
 270 extern unsigned int prefix6_bit (const struct in6_addr *prefix, const u_char prefixlen);
 271
 272 extern struct prefix *prefix_new (void);
 273 extern void prefix_free (struct prefix *);
 274 extern const char *prefix_family_str (const struct prefix *);
 275 extern int prefix_blen (const struct prefix *);
 276 extern int str2prefix (const char *, struct prefix *);
 277
 278 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 279
 280 extern const char *prefix2str (union prefixconstptr, char *, int);
 281 extern int prefix_match (const struct prefix *, const struct prefix *);
 282 extern int prefix_same (const struct prefix *, const struct prefix *);
 283 extern int prefix_cmp (const struct prefix *, const struct prefix *);
 284 extern int prefix_common_bits (const struct prefix *, const struct prefix *);
 285 extern void prefix_copy (struct prefix *dest, const struct prefix *src);
 286 extern void apply_mask (struct prefix *);
 287
 288 extern struct prefix *sockunion2prefix (const union sockunion *dest,
 289                                         const union sockunion *mask);
 290 extern struct prefix *sockunion2hostprefix (const union sockunion *, struct prefix *p);
 291 extern void prefix2sockunion (const struct prefix *, union sockunion *);
 292
 293 extern int str2prefix_eth (const char *, struct prefix_eth *);
 294
 295 extern struct prefix_ipv4 *prefix_ipv4_new (void);
 296 extern void prefix_ipv4_free (struct prefix_ipv4 *);
 297 extern int str2prefix_ipv4 (const char *, struct prefix_ipv4 *);
 298 extern void apply_mask_ipv4 (struct prefix_ipv4 *);
 299
 300 #define PREFIX_COPY_IPV4(DST, SRC)      \
 301         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 302
 303 extern int prefix_ipv4_any (const struct prefix_ipv4 *);
 304 extern void apply_classful_mask_ipv4 (struct prefix_ipv4 *);
 305
 306 extern u_char ip_masklen (struct in_addr);
 307 extern void masklen2ip (const int, struct in_addr *);
 308 /* returns the network portion of the host address */
 309 extern in_addr_t ipv4_network_addr (in_addr_t hostaddr, int masklen);
 310 /* given the address of a host on a network and the network mask length,
 311  * calculate the broadcast address for that network;
 312  * special treatment for /31: returns the address of the other host
 313  * on the network by flipping the host bit */
 314 extern in_addr_t ipv4_broadcast_addr (in_addr_t hostaddr, int masklen);
 315
 316 extern int netmask_str2prefix_str (const char *, const char *, char *);
 317
 318 extern struct prefix_ipv6 *prefix_ipv6_new (void);
 319 extern void prefix_ipv6_free (struct prefix_ipv6 *);
 320 extern int str2prefix_ipv6 (const char *, struct prefix_ipv6 *);
 321 extern void apply_mask_ipv6 (struct prefix_ipv6 *);
 322
 323 #define PREFIX_COPY_IPV6(DST, SRC)      \
 324         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 325
 326 extern int ip6_masklen (struct in6_addr);
 327 extern void masklen2ip6 (const int, struct in6_addr *);
 328
 329 extern const char *inet6_ntoa (struct in6_addr);
 330
 331 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 332 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 333
 334 static inline int ipv6_martian (struct in6_addr *addr)
 335 {
 336   struct in6_addr localhost_addr;
 337
 338   inet_pton (AF_INET6, "::1", &localhost_addr);
 339
 340   if (IPV6_ADDR_SAME(&localhost_addr, addr))
 341     return 1;
 342
 343   return 0;
 344 }
 345
 346 extern int all_digit (const char *);
 347
 348 /* NOTE: This routine expects the address argument in network byte order. */
 349 static inline int ipv4_martian (struct in_addr *addr)
 350 {
 351   in_addr_t ip = ntohl(addr->s_addr);
 352
 353   if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 354     return 1;
 355   }
 356   return 0;
 357 }
 358
 359 static inline int
 360 is_default_prefix (struct prefix *p)
 361 {
 362   if (!p)
 363     return 0;
 364
 365   if (((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY))
 366       || ((p->family == AF_INET6) &&
 367           !memcmp(&p->u.prefix6, &in6addr_any, sizeof (struct in6_addr))))
 368     return 1;
 369
 370   return 0;
 371 }
 372
 373 #endif /* _ZEBRA_PREFIX_H */