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 #include "ipaddr.h"
  36 #include "compiler.h"
  37
  38 #ifndef ETH_ALEN
  39 #define ETH_ALEN 6
  40 #endif
  41
  42 /* for compatibility */
  43 #ifdef ETHER_ADDR_LEN
  44 #undef ETHER_ADDR_LEN
  45 #endif
  46 #define ETHER_ADDR_LEN 6 CPP_WARN("ETHER_ADDR_LEN is being replaced by ETH_ALEN.\\n")
  47
  48 #define ETHER_ADDR_STRLEN (3*ETH_ALEN)
  49 /*
  50  * there isn't a portable ethernet address type. We define our
  51  * own to simplify internal handling
  52  */
  53 struct ethaddr {
  54         u_char octet[ETH_ALEN];
  55 } __attribute__((packed));
  56
  57
  58 /* length is the number of valuable bits of prefix structure
  59 * 18 bytes is current length in structure, if address is ipv4
  60 * 30 bytes is in case of ipv6
  61 */
  62 #define PREFIX_LEN_ROUTE_TYPE_5_IPV4 (18*8)
  63 #define PREFIX_LEN_ROUTE_TYPE_5_IPV6 (30*8)
  64
  65 /* EVPN address (RFC 7432) */
  66 struct evpn_addr {
  67         u_char route_type;
  68         u_char ip_prefix_length;
  69         struct ethaddr mac;
  70         uint32_t eth_tag;
  71         struct ipaddr ip;
  72 #if 0
  73   union
  74   {
  75     u_char addr;
  76     struct in_addr v4_addr;
  77     struct in6_addr v6_addr;
  78   } ip;
  79 #endif
  80 };
  81
  82 #define IS_EVPN_PREFIX_IPADDR_NONE(evp)  IS_IPADDR_NONE(&(evp)->prefix.ip)
  83 #define IS_EVPN_PREFIX_IPADDR_V4(evp)    IS_IPADDR_V4(&(evp)->prefix.ip)
  84 #define IS_EVPN_PREFIX_IPADDR_V6(evp)    IS_IPADDR_V6(&(evp)->prefix.ip)
  85
  86 /*
  87  * A struct prefix contains an address family, a prefix length, and an
  88  * address.  This can represent either a 'network prefix' as defined
  89  * by CIDR, where the 'host bits' of the prefix are 0
  90  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
  91  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
  92  * interface.
  93  */
  94
  95 /* different OSes use different names */
  96 #if defined(AF_PACKET)
  97 #define AF_ETHERNET AF_PACKET
  98 #else
  99 #if defined(AF_LINK)
 100 #define AF_ETHERNET AF_LINK
 101 #endif
 102 #endif
 103
 104 /* The 'family' in the prefix structure is internal to FRR and need not
 105  * map to standard OS AF_ definitions except where needed for interacting
 106  * with the kernel. However, AF_ definitions are currently in use and
 107  * prevalent across the code. Define a new FRR-specific AF for EVPN to
 108  * distinguish between 'ethernet' (MAC-only) and 'evpn' prefixes and
 109  * ensure it does not conflict with any OS AF_ definition.
 110  */
 111 #if !defined(AF_EVPN)
 112 #define AF_EVPN (AF_MAX + 1)
 113 #endif
 114
 115 /* FRR generic prefix structure. */
 116 struct prefix {
 117         u_char family;
 118         u_char prefixlen;
 119         union {
 120                 u_char prefix;
 121                 struct in_addr prefix4;
 122                 struct in6_addr prefix6;
 123                 struct {
 124                         struct in_addr id;
 125                         struct in_addr adv_router;
 126                 } lp;
 127                 struct ethaddr prefix_eth; /* AF_ETHERNET */
 128                 u_char val[16];
 129                 uintptr_t ptr;
 130                 struct evpn_addr prefix_evpn; /* AF_EVPN */
 131         } u __attribute__((aligned(8)));
 132 };
 133
 134 /* IPv4 prefix structure. */
 135 struct prefix_ipv4 {
 136         u_char family;
 137         u_char prefixlen;
 138         struct in_addr prefix __attribute__((aligned(8)));
 139 };
 140
 141 /* IPv6 prefix structure. */
 142 struct prefix_ipv6 {
 143         u_char family;
 144         u_char prefixlen;
 145         struct in6_addr prefix __attribute__((aligned(8)));
 146 };
 147
 148 struct prefix_ls {
 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         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         u_char family;
 165         u_char prefixlen;
 166         struct ethaddr eth_addr __attribute__((aligned(8))); /* AF_ETHERNET */
 167 };
 168
 169 /* EVPN prefix structure. */
 170 struct prefix_evpn {
 171         u_char family;
 172         u_char prefixlen;
 173         struct evpn_addr prefix __attribute__((aligned(8)));
 174 };
 175
 176 /* Prefix for a generic pointer */
 177 struct prefix_ptr {
 178         u_char family;
 179         u_char prefixlen;
 180         uintptr_t prefix __attribute__((aligned(8)));
 181 };
 182
 183 struct prefix_sg {
 184         u_char family;
 185         u_char prefixlen;
 186         struct in_addr src __attribute__((aligned(8)));
 187         struct in_addr grp;
 188 };
 189
 190 /* helper to get type safety/avoid casts on calls
 191  * (w/o this, functions accepting all prefix types need casts on the caller
 192  * side, which strips type safety since the cast will accept any pointer
 193  * type.)
 194  */
 195 union prefixptr {
 196         struct prefix *p;
 197         struct prefix_ipv4 *p4;
 198         struct prefix_ipv6 *p6;
 199         struct prefix_evpn *evp;
 200 } __attribute__((transparent_union));
 201
 202 union prefixconstptr {
 203         const struct prefix *p;
 204         const struct prefix_ipv4 *p4;
 205         const struct prefix_ipv6 *p6;
 206         const struct prefix_evpn *evp;
 207 } __attribute__((transparent_union));
 208
 209 #ifndef INET_ADDRSTRLEN
 210 #define INET_ADDRSTRLEN 16
 211 #endif /* INET_ADDRSTRLEN */
 212
 213 #ifndef INET6_ADDRSTRLEN
 214 #define INET6_ADDRSTRLEN 46
 215 #endif /* INET6_ADDRSTRLEN */
 216
 217 #ifndef INET6_BUFSIZ
 218 #define INET6_BUFSIZ 51
 219 #endif /* INET6_BUFSIZ */
 220
 221 /* Maximum prefix string length (IPv6) */
 222 #define PREFIX_STRLEN 51
 223
 224 /* Max bit/byte length of IPv4 address. */
 225 #define IPV4_MAX_BYTELEN    4
 226 #define IPV4_MAX_BITLEN    32
 227 #define IPV4_MAX_PREFIXLEN 32
 228 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 229
 230 static inline bool ipv4_addr_same(const struct in_addr *a,
 231                                   const struct in_addr *b)
 232 {
 233         return (a->s_addr == b->s_addr);
 234 }
 235 #define IPV4_ADDR_SAME(A,B)  ipv4_addr_same((A), (B))
 236
 237 static inline void ipv4_addr_copy(struct in_addr *dst,
 238                                   const struct in_addr *src)
 239 {
 240         dst->s_addr = src->s_addr;
 241 }
 242 #define IPV4_ADDR_COPY(D,S)  ipv4_addr_copy((D), (S))
 243
 244 #define IPV4_NET0(a)    ((((u_int32_t) (a)) & 0xff000000) == 0x00000000)
 245 #define IPV4_NET127(a)  ((((u_int32_t) (a)) & 0xff000000) == 0x7f000000)
 246 #define IPV4_LINKLOCAL(a) ((((u_int32_t) (a)) & 0xffff0000) == 0xa9fe0000)
 247 #define IPV4_CLASS_DE(a)  ((((u_int32_t) (a)) & 0xe0000000) == 0xe0000000)
 248
 249 /* Max bit/byte length of IPv6 address. */
 250 #define IPV6_MAX_BYTELEN    16
 251 #define IPV6_MAX_BITLEN    128
 252 #define IPV6_MAX_PREFIXLEN 128
 253 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 254 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 255 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 256
 257 /* Count prefix size from mask length */
 258 #define PSIZE(a) (((a) + 7) / (8))
 259
 260 #define BSIZE(a) ((a) * (8))
 261
 262 /* Prefix's family member. */
 263 #define PREFIX_FAMILY(p)  ((p)->family)
 264
 265 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 266 #ifndef s6_addr32
 267 #if defined(SUNOS_5)
 268 /* Some SunOS define s6_addr32 only to kernel */
 269 #define s6_addr32 _S6_un._S6_u32
 270 #else
 271 #define s6_addr32 __u6_addr.__u6_addr32
 272 #endif /* SUNOS_5 */
 273 #endif /*s6_addr32*/
 274
 275 /* Prototypes. */
 276 extern int str2family(const char *);
 277 extern int afi2family(afi_t);
 278 extern afi_t family2afi(int);
 279 extern const char *safi2str(safi_t safi);
 280 extern const char *afi2str(afi_t afi);
 281
 282 /* Check bit of the prefix. */
 283 extern unsigned int prefix_bit(const u_char *prefix, const u_char prefixlen);
 284 extern unsigned int prefix6_bit(const struct in6_addr *prefix,
 285                                 const u_char prefixlen);
 286
 287 extern struct prefix *prefix_new(void);
 288 extern void prefix_free(struct prefix *);
 289 extern const char *prefix_family_str(const struct prefix *);
 290 extern int prefix_blen(const struct prefix *);
 291 extern int str2prefix(const char *, struct prefix *);
 292
 293 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 294
 295 extern const char *prefix2str(union prefixconstptr, char *, int);
 296 extern int prefix_match(const struct prefix *, const struct prefix *);
 297 extern int prefix_match_network_statement(const struct prefix *,
 298                                           const struct prefix *);
 299 extern int prefix_same(const struct prefix *, const struct prefix *);
 300 extern int prefix_cmp(const struct prefix *, const struct prefix *);
 301 extern int prefix_common_bits(const struct prefix *, const struct prefix *);
 302 extern void prefix_copy(struct prefix *dest, const struct prefix *src);
 303 extern void apply_mask(struct prefix *);
 304
 305 extern struct prefix *sockunion2prefix(const union sockunion *dest,
 306                                        const union sockunion *mask);
 307 extern struct prefix *sockunion2hostprefix(const union sockunion *,
 308                                            struct prefix *p);
 309 extern void prefix2sockunion(const struct prefix *, union sockunion *);
 310
 311 extern int str2prefix_eth(const char *, struct prefix_eth *);
 312
 313 extern struct prefix_ipv4 *prefix_ipv4_new(void);
 314 extern void prefix_ipv4_free(struct prefix_ipv4 *);
 315 extern int str2prefix_ipv4(const char *, struct prefix_ipv4 *);
 316 extern void apply_mask_ipv4(struct prefix_ipv4 *);
 317
 318 #define PREFIX_COPY(DST, SRC)                                        \
 319         *((struct prefix *)(DST)) = *((const struct prefix *)(SRC))
 320 #define PREFIX_COPY_IPV4(DST, SRC)                                   \
 321         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 322
 323 extern int prefix_ipv4_any(const struct prefix_ipv4 *);
 324 extern void apply_classful_mask_ipv4(struct prefix_ipv4 *);
 325
 326 extern u_char ip_masklen(struct in_addr);
 327 extern void masklen2ip(const int, struct in_addr *);
 328 /* returns the network portion of the host address */
 329 extern in_addr_t ipv4_network_addr(in_addr_t hostaddr, int masklen);
 330 /* given the address of a host on a network and the network mask length,
 331  * calculate the broadcast address for that network;
 332  * special treatment for /31: returns the address of the other host
 333  * on the network by flipping the host bit */
 334 extern in_addr_t ipv4_broadcast_addr(in_addr_t hostaddr, int masklen);
 335
 336 extern int netmask_str2prefix_str(const char *, const char *, char *);
 337
 338 extern struct prefix_ipv6 *prefix_ipv6_new(void);
 339 extern void prefix_ipv6_free(struct prefix_ipv6 *);
 340 extern int str2prefix_ipv6(const char *, struct prefix_ipv6 *);
 341 extern void apply_mask_ipv6(struct prefix_ipv6 *);
 342
 343 #define PREFIX_COPY_IPV6(DST, SRC)                                             \
 344         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 345
 346 extern int ip6_masklen(struct in6_addr);
 347 extern void masklen2ip6(const int, struct in6_addr *);
 348
 349 extern const char *inet6_ntoa(struct in6_addr);
 350
 351 extern int is_zero_mac(struct ethaddr *mac);
 352 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 353 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 354
 355 extern unsigned prefix_hash_key(void *pp);
 356
 357 static inline int ipv6_martian(struct in6_addr *addr)
 358 {
 359         struct in6_addr localhost_addr;
 360
 361         inet_pton(AF_INET6, "::1", &localhost_addr);
 362
 363         if (IPV6_ADDR_SAME(&localhost_addr, addr))
 364                 return 1;
 365
 366         return 0;
 367 }
 368
 369 extern int all_digit(const char *);
 370 extern int macstr2prefix_evpn(const char *str, struct prefix_evpn *p);
 371
 372 /* NOTE: This routine expects the address argument in network byte order. */
 373 static inline int ipv4_martian(struct in_addr *addr)
 374 {
 375         in_addr_t ip = ntohl(addr->s_addr);
 376
 377         if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 378                 return 1;
 379         }
 380         return 0;
 381 }
 382
 383 static inline int is_default_prefix(const struct prefix *p)
 384 {
 385         if (!p)
 386                 return 0;
 387
 388         if ((p->family == AF_INET) &&
 389             (p->u.prefix4.s_addr == INADDR_ANY) &&
 390             (p->prefixlen == 0))
 391                 return 1;
 392
 393         if ((p->family == AF_INET6) &&
 394             (p->prefixlen == 0) &&
 395             (!memcmp(&p->u.prefix6, &in6addr_any,
 396                      sizeof(struct in6_addr))))
 397                 return 1;
 398
 399         return 0;
 400 }
 401
 402 static inline int is_host_route(struct prefix *p)
 403 {
 404         if (p->family == AF_INET)
 405                 return (p->prefixlen == IPV4_MAX_BITLEN);
 406         else if (p->family == AF_INET6)
 407                 return (p->prefixlen == IPV6_MAX_BITLEN);
 408         return 0;
 409 }
 410
 411 #endif /* _ZEBRA_PREFIX_H */