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 #define ETHER_ADDR_STRLEN (3*ETH_ALEN)
  43 /*
  44  * there isn't a portable ethernet address type. We define our
  45  * own to simplify internal handling
  46  */
  47 struct ethaddr {
  48         uint8_t octet[ETH_ALEN];
  49 } __attribute__((packed));
  50
  51
  52 /* length is the number of valuable bits of prefix structure
  53 * 18 bytes is current length in structure, if address is ipv4
  54 * 30 bytes is in case of ipv6
  55 */
  56 #define PREFIX_LEN_ROUTE_TYPE_5_IPV4 (18*8)
  57 #define PREFIX_LEN_ROUTE_TYPE_5_IPV6 (30*8)
  58
  59 /* EVPN address (RFC 7432) */
  60 struct evpn_addr {
  61         uint8_t route_type;
  62         uint8_t ip_prefix_length;
  63         struct ethaddr mac;
  64         uint32_t eth_tag;
  65         struct ipaddr ip;
  66 #if 0
  67   union
  68   {
  69     uint8_t addr;
  70     struct in_addr v4_addr;
  71     struct in6_addr v6_addr;
  72   } ip;
  73 #endif
  74 };
  75
  76 #define IS_EVPN_PREFIX_IPADDR_NONE(evp)  IS_IPADDR_NONE(&(evp)->prefix.ip)
  77 #define IS_EVPN_PREFIX_IPADDR_V4(evp)    IS_IPADDR_V4(&(evp)->prefix.ip)
  78 #define IS_EVPN_PREFIX_IPADDR_V6(evp)    IS_IPADDR_V6(&(evp)->prefix.ip)
  79
  80 /*
  81  * A struct prefix contains an address family, a prefix length, and an
  82  * address.  This can represent either a 'network prefix' as defined
  83  * by CIDR, where the 'host bits' of the prefix are 0
  84  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
  85  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
  86  * interface.
  87  */
  88
  89 /* different OSes use different names */
  90 #if defined(AF_PACKET)
  91 #define AF_ETHERNET AF_PACKET
  92 #else
  93 #if defined(AF_LINK)
  94 #define AF_ETHERNET AF_LINK
  95 #endif
  96 #endif
  97
  98 /* The 'family' in the prefix structure is internal to FRR and need not
  99  * map to standard OS AF_ definitions except where needed for interacting
 100  * with the kernel. However, AF_ definitions are currently in use and
 101  * prevalent across the code. Define a new FRR-specific AF for EVPN to
 102  * distinguish between 'ethernet' (MAC-only) and 'evpn' prefixes and
 103  * ensure it does not conflict with any OS AF_ definition.
 104  */
 105 #if !defined(AF_EVPN)
 106 #define AF_EVPN (AF_MAX + 1)
 107 #endif
 108
 109 #if !defined(AF_FLOWSPEC)
 110 #define AF_FLOWSPEC (AF_MAX + 2)
 111 #endif
 112
 113 struct flowspec_prefix {
 114         uint16_t prefixlen; /* length in bytes */
 115         uintptr_t ptr;
 116 };
 117
 118 /* FRR generic prefix structure. */
 119 struct prefix {
 120         uint8_t family;
 121         uint8_t prefixlen;
 122         union {
 123                 uint8_t prefix;
 124                 struct in_addr prefix4;
 125                 struct in6_addr prefix6;
 126                 struct {
 127                         struct in_addr id;
 128                         struct in_addr adv_router;
 129                 } lp;
 130                 struct ethaddr prefix_eth; /* AF_ETHERNET */
 131                 uint8_t val[16];
 132                 uintptr_t ptr;
 133                 struct evpn_addr prefix_evpn; /* AF_EVPN */
 134                 struct flowspec_prefix prefix_flowspec; /* AF_FLOWSPEC */
 135         } u __attribute__((aligned(8)));
 136 };
 137
 138 /* IPv4 prefix structure. */
 139 struct prefix_ipv4 {
 140         uint8_t family;
 141         uint8_t prefixlen;
 142         struct in_addr prefix __attribute__((aligned(8)));
 143 };
 144
 145 /* IPv6 prefix structure. */
 146 struct prefix_ipv6 {
 147         uint8_t family;
 148         uint8_t prefixlen;
 149         struct in6_addr prefix __attribute__((aligned(8)));
 150 };
 151
 152 struct prefix_ls {
 153         uint8_t family;
 154         uint8_t prefixlen;
 155         struct in_addr id __attribute__((aligned(8)));
 156         struct in_addr adv_router;
 157 };
 158
 159 /* Prefix for routing distinguisher. */
 160 struct prefix_rd {
 161         uint8_t family;
 162         uint8_t prefixlen;
 163         uint8_t val[8] __attribute__((aligned(8)));
 164 };
 165
 166 /* Prefix for ethernet. */
 167 struct prefix_eth {
 168         uint8_t family;
 169         uint8_t prefixlen;
 170         struct ethaddr eth_addr __attribute__((aligned(8))); /* AF_ETHERNET */
 171 };
 172
 173 /* EVPN prefix structure. */
 174 struct prefix_evpn {
 175         uint8_t family;
 176         uint8_t prefixlen;
 177         struct evpn_addr prefix __attribute__((aligned(8)));
 178 };
 179
 180 /* Prefix for a generic pointer */
 181 struct prefix_ptr {
 182         uint8_t family;
 183         uint8_t prefixlen;
 184         uintptr_t prefix __attribute__((aligned(8)));
 185 };
 186
 187 /* Prefix for a Flowspec entry */
 188 struct prefix_fs {
 189         uint8_t family;
 190         uint8_t prefixlen; /* unused */
 191         struct flowspec_prefix  prefix __attribute__((aligned(8)));
 192 };
 193
 194 struct prefix_sg {
 195         uint8_t family;
 196         uint8_t prefixlen;
 197         struct in_addr src __attribute__((aligned(8)));
 198         struct in_addr grp;
 199 };
 200
 201 /* helper to get type safety/avoid casts on calls
 202  * (w/o this, functions accepting all prefix types need casts on the caller
 203  * side, which strips type safety since the cast will accept any pointer
 204  * type.)
 205  */
 206 union prefixptr {
 207         struct prefix *p;
 208         struct prefix_ipv4 *p4;
 209         struct prefix_ipv6 *p6;
 210         struct prefix_evpn *evp;
 211         const struct prefix_fs *fs;
 212 } __attribute__((transparent_union));
 213
 214 union prefixconstptr {
 215         const struct prefix *p;
 216         const struct prefix_ipv4 *p4;
 217         const struct prefix_ipv6 *p6;
 218         const struct prefix_evpn *evp;
 219         const struct prefix_fs *fs;
 220 } __attribute__((transparent_union));
 221
 222 #ifndef INET_ADDRSTRLEN
 223 #define INET_ADDRSTRLEN 16
 224 #endif /* INET_ADDRSTRLEN */
 225
 226 #ifndef INET6_ADDRSTRLEN
 227 #define INET6_ADDRSTRLEN 46
 228 #endif /* INET6_ADDRSTRLEN */
 229
 230 #ifndef INET6_BUFSIZ
 231 #define INET6_BUFSIZ 51
 232 #endif /* INET6_BUFSIZ */
 233
 234 /* Maximum prefix string length (IPv6) */
 235 #define PREFIX_STRLEN 51
 236
 237 /* Max bit/byte length of IPv4 address. */
 238 #define IPV4_MAX_BYTELEN    4
 239 #define IPV4_MAX_BITLEN    32
 240 #define IPV4_MAX_PREFIXLEN 32
 241 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 242
 243 static inline bool ipv4_addr_same(const struct in_addr *a,
 244                                   const struct in_addr *b)
 245 {
 246         return (a->s_addr == b->s_addr);
 247 }
 248 #define IPV4_ADDR_SAME(A,B)  ipv4_addr_same((A), (B))
 249
 250 static inline void ipv4_addr_copy(struct in_addr *dst,
 251                                   const struct in_addr *src)
 252 {
 253         dst->s_addr = src->s_addr;
 254 }
 255 #define IPV4_ADDR_COPY(D,S)  ipv4_addr_copy((D), (S))
 256
 257 #define IPV4_NET0(a) ((((uint32_t)(a)) & 0xff000000) == 0x00000000)
 258 #define IPV4_NET127(a) ((((uint32_t)(a)) & 0xff000000) == 0x7f000000)
 259 #define IPV4_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffff0000) == 0xa9fe0000)
 260 #define IPV4_CLASS_DE(a) ((((uint32_t)(a)) & 0xe0000000) == 0xe0000000)
 261 #define IPV4_MC_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffffff00) == 0xe0000000)
 262
 263 /* Max bit/byte length of IPv6 address. */
 264 #define IPV6_MAX_BYTELEN    16
 265 #define IPV6_MAX_BITLEN    128
 266 #define IPV6_MAX_PREFIXLEN 128
 267 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 268 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 269 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 270
 271 /* Count prefix size from mask length */
 272 #define PSIZE(a) (((a) + 7) / (8))
 273
 274 #define BSIZE(a) ((a) * (8))
 275
 276 /* Prefix's family member. */
 277 #define PREFIX_FAMILY(p)  ((p)->family)
 278
 279 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 280 #ifndef s6_addr32
 281 #if defined(SUNOS_5)
 282 /* Some SunOS define s6_addr32 only to kernel */
 283 #define s6_addr32 _S6_un._S6_u32
 284 #else
 285 #define s6_addr32 __u6_addr.__u6_addr32
 286 #endif /* SUNOS_5 */
 287 #endif /*s6_addr32*/
 288
 289 /* Prototypes. */
 290 extern int str2family(const char *);
 291 extern int afi2family(afi_t);
 292 extern afi_t family2afi(int);
 293 extern const char *family2str(int family);
 294 extern const char *safi2str(safi_t safi);
 295 extern const char *afi2str(afi_t afi);
 296
 297 /* Check bit of the prefix. */
 298 extern unsigned int prefix_bit(const uint8_t *prefix, const uint8_t prefixlen);
 299 extern unsigned int prefix6_bit(const struct in6_addr *prefix,
 300                                 const uint8_t prefixlen);
 301
 302 extern struct prefix *prefix_new(void);
 303 extern void prefix_free(struct prefix *);
 304 extern const char *prefix_family_str(const struct prefix *);
 305 extern int prefix_blen(const struct prefix *);
 306 extern int str2prefix(const char *, struct prefix *);
 307
 308 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 309
 310 extern const char *prefix2str(union prefixconstptr, char *, int);
 311 extern int prefix_match(const struct prefix *, const struct prefix *);
 312 extern int prefix_match_network_statement(const struct prefix *,
 313                                           const struct prefix *);
 314 extern int prefix_same(const struct prefix *, const struct prefix *);
 315 extern int prefix_cmp(const struct prefix *, const struct prefix *);
 316 extern int prefix_common_bits(const struct prefix *, const struct prefix *);
 317 extern void prefix_copy(struct prefix *dest, const struct prefix *src);
 318 extern void apply_mask(struct prefix *);
 319
 320 extern struct prefix *sockunion2prefix(const union sockunion *dest,
 321                                        const union sockunion *mask);
 322 extern struct prefix *sockunion2hostprefix(const union sockunion *,
 323                                            struct prefix *p);
 324 extern void prefix2sockunion(const struct prefix *, union sockunion *);
 325
 326 extern int str2prefix_eth(const char *, struct prefix_eth *);
 327
 328 extern struct prefix_ipv4 *prefix_ipv4_new(void);
 329 extern void prefix_ipv4_free(struct prefix_ipv4 *);
 330 extern int str2prefix_ipv4(const char *, struct prefix_ipv4 *);
 331 extern void apply_mask_ipv4(struct prefix_ipv4 *);
 332
 333 #define PREFIX_COPY(DST, SRC)                                                  \
 334         *((struct prefix *)(DST)) = *((const struct prefix *)(SRC))
 335 #define PREFIX_COPY_IPV4(DST, SRC)                                             \
 336         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 337
 338 extern int prefix_ipv4_any(const struct prefix_ipv4 *);
 339 extern void apply_classful_mask_ipv4(struct prefix_ipv4 *);
 340
 341 extern uint8_t ip_masklen(struct in_addr);
 342 extern void masklen2ip(const int, struct in_addr *);
 343 /* returns the network portion of the host address */
 344 extern in_addr_t ipv4_network_addr(in_addr_t hostaddr, int masklen);
 345 /* given the address of a host on a network and the network mask length,
 346  * calculate the broadcast address for that network;
 347  * special treatment for /31: returns the address of the other host
 348  * on the network by flipping the host bit */
 349 extern in_addr_t ipv4_broadcast_addr(in_addr_t hostaddr, int masklen);
 350
 351 extern int netmask_str2prefix_str(const char *, const char *, char *);
 352
 353 extern struct prefix_ipv6 *prefix_ipv6_new(void);
 354 extern void prefix_ipv6_free(struct prefix_ipv6 *);
 355 extern int str2prefix_ipv6(const char *, struct prefix_ipv6 *);
 356 extern void apply_mask_ipv6(struct prefix_ipv6 *);
 357
 358 #define PREFIX_COPY_IPV6(DST, SRC)                                             \
 359         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 360
 361 extern int ip6_masklen(struct in6_addr);
 362 extern void masklen2ip6(const int, struct in6_addr *);
 363
 364 extern const char *inet6_ntoa(struct in6_addr);
 365
 366 extern int is_zero_mac(struct ethaddr *mac);
 367 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 368 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 369
 370 extern unsigned prefix_hash_key(void *pp);
 371
 372 static inline int ipv6_martian(struct in6_addr *addr)
 373 {
 374         struct in6_addr localhost_addr;
 375
 376         inet_pton(AF_INET6, "::1", &localhost_addr);
 377
 378         if (IPV6_ADDR_SAME(&localhost_addr, addr))
 379                 return 1;
 380
 381         return 0;
 382 }
 383
 384 extern int all_digit(const char *);
 385 extern int macstr2prefix_evpn(const char *str, struct prefix_evpn *p);
 386
 387 /* NOTE: This routine expects the address argument in network byte order. */
 388 static inline int ipv4_martian(struct in_addr *addr)
 389 {
 390         in_addr_t ip = ntohl(addr->s_addr);
 391
 392         if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 393                 return 1;
 394         }
 395         return 0;
 396 }
 397
 398 static inline int is_default_prefix(const struct prefix *p)
 399 {
 400         if (!p)
 401                 return 0;
 402
 403         if ((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY)
 404             && (p->prefixlen == 0))
 405                 return 1;
 406
 407         if ((p->family == AF_INET6) && (p->prefixlen == 0)
 408             && (!memcmp(&p->u.prefix6, &in6addr_any, sizeof(struct in6_addr))))
 409                 return 1;
 410
 411         return 0;
 412 }
 413
 414 static inline int is_host_route(struct prefix *p)
 415 {
 416         if (p->family == AF_INET)
 417                 return (p->prefixlen == IPV4_MAX_BITLEN);
 418         else if (p->family == AF_INET6)
 419                 return (p->prefixlen == IPV6_MAX_BITLEN);
 420         return 0;
 421 }
 422
 423 #endif /* _ZEBRA_PREFIX_H */