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 ESI_BYTES 10
  43 #define ESI_STR_LEN (3 * ESI_BYTES)
  44
  45 #define ETHER_ADDR_STRLEN (3*ETH_ALEN)
  46 /*
  47  * there isn't a portable ethernet address type. We define our
  48  * own to simplify internal handling
  49  */
  50 struct ethaddr {
  51         uint8_t octet[ETH_ALEN];
  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 typedef struct esi_t_ {
  63         uint8_t val[10];
  64 } esi_t;
  65
  66 struct evpn_ead_addr {
  67         esi_t esi;
  68         uint32_t eth_tag;
  69 };
  70
  71 struct evpn_macip_addr {
  72         uint32_t eth_tag;
  73         uint8_t ip_prefix_length;
  74         struct ethaddr mac;
  75         struct ipaddr ip;
  76 };
  77
  78 struct evpn_imet_addr {
  79         uint32_t eth_tag;
  80         uint8_t ip_prefix_length;
  81         struct ipaddr ip;
  82 };
  83
  84 struct evpn_es_addr {
  85         esi_t esi;
  86         uint8_t ip_prefix_length;
  87         struct ipaddr ip;
  88 };
  89
  90 struct evpn_prefix_addr {
  91         uint32_t eth_tag;
  92         uint8_t ip_prefix_length;
  93         struct ipaddr ip;
  94 };
  95
  96 /* EVPN address (RFC 7432) */
  97 struct evpn_addr {
  98         uint8_t route_type;
  99         union {
 100                 struct evpn_ead_addr _ead_addr;
 101                 struct evpn_macip_addr _macip_addr;
 102                 struct evpn_imet_addr _imet_addr;
 103                 struct evpn_es_addr _es_addr;
 104                 struct evpn_prefix_addr _prefix_addr;
 105         } u;
 106 #define ead_addr u._ead_addr
 107 #define macip_addr u._macip_addr
 108 #define imet_addr u._imet_addr
 109 #define es_addr u._es_addr
 110 #define prefix_addr u._prefix_addr
 111 };
 112
 113 /*
 114  * A struct prefix contains an address family, a prefix length, and an
 115  * address.  This can represent either a 'network prefix' as defined
 116  * by CIDR, where the 'host bits' of the prefix are 0
 117  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
 118  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
 119  * interface.
 120  */
 121
 122 /* different OSes use different names */
 123 #if defined(AF_PACKET)
 124 #define AF_ETHERNET AF_PACKET
 125 #else
 126 #if defined(AF_LINK)
 127 #define AF_ETHERNET AF_LINK
 128 #endif
 129 #endif
 130
 131 /* The 'family' in the prefix structure is internal to FRR and need not
 132  * map to standard OS AF_ definitions except where needed for interacting
 133  * with the kernel. However, AF_ definitions are currently in use and
 134  * prevalent across the code. Define a new FRR-specific AF for EVPN to
 135  * distinguish between 'ethernet' (MAC-only) and 'evpn' prefixes and
 136  * ensure it does not conflict with any OS AF_ definition.
 137  */
 138 #if !defined(AF_EVPN)
 139 #define AF_EVPN (AF_MAX + 1)
 140 #endif
 141
 142 #if !defined(AF_FLOWSPEC)
 143 #define AF_FLOWSPEC (AF_MAX + 2)
 144 #endif
 145
 146 struct flowspec_prefix {
 147         uint16_t prefixlen; /* length in bytes */
 148         uintptr_t ptr;
 149 };
 150
 151 /* FRR generic prefix structure. */
 152 struct prefix {
 153         uint8_t family;
 154         uint8_t prefixlen;
 155         union {
 156                 uint8_t prefix;
 157                 struct in_addr prefix4;
 158                 struct in6_addr prefix6;
 159                 struct {
 160                         struct in_addr id;
 161                         struct in_addr adv_router;
 162                 } lp;
 163                 struct ethaddr prefix_eth; /* AF_ETHERNET */
 164                 uint8_t val[16];
 165                 uintptr_t ptr;
 166                 struct evpn_addr prefix_evpn; /* AF_EVPN */
 167                 struct flowspec_prefix prefix_flowspec; /* AF_FLOWSPEC */
 168         } u __attribute__((aligned(8)));
 169 };
 170
 171 /* IPv4 prefix structure. */
 172 struct prefix_ipv4 {
 173         uint8_t family;
 174         uint8_t prefixlen;
 175         struct in_addr prefix __attribute__((aligned(8)));
 176 };
 177
 178 /* IPv6 prefix structure. */
 179 struct prefix_ipv6 {
 180         uint8_t family;
 181         uint8_t prefixlen;
 182         struct in6_addr prefix __attribute__((aligned(8)));
 183 };
 184
 185 struct prefix_ls {
 186         uint8_t family;
 187         uint8_t prefixlen;
 188         struct in_addr id __attribute__((aligned(8)));
 189         struct in_addr adv_router;
 190 };
 191
 192 /* Prefix for routing distinguisher. */
 193 struct prefix_rd {
 194         uint8_t family;
 195         uint8_t prefixlen;
 196         uint8_t val[8] __attribute__((aligned(8)));
 197 };
 198
 199 /* Prefix for ethernet. */
 200 struct prefix_eth {
 201         uint8_t family;
 202         uint8_t prefixlen;
 203         struct ethaddr eth_addr __attribute__((aligned(8))); /* AF_ETHERNET */
 204 };
 205
 206 /* EVPN prefix structure. */
 207 struct prefix_evpn {
 208         uint8_t family;
 209         uint8_t prefixlen;
 210         struct evpn_addr prefix __attribute__((aligned(8)));
 211 };
 212
 213 static inline int is_evpn_prefix_ipaddr_none(const struct prefix_evpn *evp)
 214 {
 215         if (evp->prefix.route_type == 2)
 216                 return IS_IPADDR_NONE(&(evp)->prefix.macip_addr.ip);
 217         if (evp->prefix.route_type == 3)
 218                 return IS_IPADDR_NONE(&(evp)->prefix.imet_addr.ip);
 219         if (evp->prefix.route_type == 4)
 220                 return IS_IPADDR_NONE(&(evp)->prefix.es_addr.ip);
 221         if (evp->prefix.route_type == 5)
 222                 return IS_IPADDR_NONE(&(evp)->prefix.prefix_addr.ip);
 223         return 0;
 224 }
 225
 226 static inline int is_evpn_prefix_ipaddr_v4(const struct prefix_evpn *evp)
 227 {
 228         if (evp->prefix.route_type == 2)
 229                 return IS_IPADDR_V4(&(evp)->prefix.macip_addr.ip);
 230         if (evp->prefix.route_type == 3)
 231                 return IS_IPADDR_V4(&(evp)->prefix.imet_addr.ip);
 232         if (evp->prefix.route_type == 4)
 233                 return IS_IPADDR_V4(&(evp)->prefix.es_addr.ip);
 234         if (evp->prefix.route_type == 5)
 235                 return IS_IPADDR_V4(&(evp)->prefix.prefix_addr.ip);
 236         return 0;
 237 }
 238
 239 static inline int is_evpn_prefix_ipaddr_v6(const struct prefix_evpn *evp)
 240 {
 241         if (evp->prefix.route_type == 2)
 242                 return IS_IPADDR_V6(&(evp)->prefix.macip_addr.ip);
 243         if (evp->prefix.route_type == 3)
 244                 return IS_IPADDR_V6(&(evp)->prefix.imet_addr.ip);
 245         if (evp->prefix.route_type == 4)
 246                 return IS_IPADDR_V6(&(evp)->prefix.es_addr.ip);
 247         if (evp->prefix.route_type == 5)
 248                 return IS_IPADDR_V6(&(evp)->prefix.prefix_addr.ip);
 249         return 0;
 250 }
 251
 252 /* Prefix for a generic pointer */
 253 struct prefix_ptr {
 254         uint8_t family;
 255         uint8_t prefixlen;
 256         uintptr_t prefix __attribute__((aligned(8)));
 257 };
 258
 259 /* Prefix for a Flowspec entry */
 260 struct prefix_fs {
 261         uint8_t family;
 262         uint8_t prefixlen; /* unused */
 263         struct flowspec_prefix  prefix __attribute__((aligned(8)));
 264 };
 265
 266 struct prefix_sg {
 267         uint8_t family;
 268         uint8_t prefixlen;
 269         struct in_addr src __attribute__((aligned(8)));
 270         struct in_addr grp;
 271 };
 272
 273 /* helper to get type safety/avoid casts on calls
 274  * (w/o this, functions accepting all prefix types need casts on the caller
 275  * side, which strips type safety since the cast will accept any pointer
 276  * type.)
 277  */
 278 union prefixptr {
 279         struct prefix *p;
 280         struct prefix_ipv4 *p4;
 281         struct prefix_ipv6 *p6;
 282         struct prefix_evpn *evp;
 283         const struct prefix_fs *fs;
 284 } __attribute__((transparent_union));
 285
 286 union prefixconstptr {
 287         const struct prefix *p;
 288         const struct prefix_ipv4 *p4;
 289         const struct prefix_ipv6 *p6;
 290         const struct prefix_evpn *evp;
 291         const struct prefix_fs *fs;
 292 } __attribute__((transparent_union));
 293
 294 #ifndef INET_ADDRSTRLEN
 295 #define INET_ADDRSTRLEN 16
 296 #endif /* INET_ADDRSTRLEN */
 297
 298 #ifndef INET6_ADDRSTRLEN
 299 #define INET6_ADDRSTRLEN 46
 300 #endif /* INET6_ADDRSTRLEN */
 301
 302 #ifndef INET6_BUFSIZ
 303 #define INET6_BUFSIZ 51
 304 #endif /* INET6_BUFSIZ */
 305
 306 /* Maximum prefix string length (IPv6) */
 307 #define PREFIX_STRLEN 51
 308
 309 /* Max bit/byte length of IPv4 address. */
 310 #define IPV4_MAX_BYTELEN    4
 311 #define IPV4_MAX_BITLEN    32
 312 #define IPV4_MAX_PREFIXLEN 32
 313 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 314
 315 static inline bool ipv4_addr_same(const struct in_addr *a,
 316                                   const struct in_addr *b)
 317 {
 318         return (a->s_addr == b->s_addr);
 319 }
 320 #define IPV4_ADDR_SAME(A,B)  ipv4_addr_same((A), (B))
 321
 322 static inline void ipv4_addr_copy(struct in_addr *dst,
 323                                   const struct in_addr *src)
 324 {
 325         dst->s_addr = src->s_addr;
 326 }
 327 #define IPV4_ADDR_COPY(D,S)  ipv4_addr_copy((D), (S))
 328
 329 #define IPV4_NET0(a) ((((uint32_t)(a)) & 0xff000000) == 0x00000000)
 330 #define IPV4_NET127(a) ((((uint32_t)(a)) & 0xff000000) == 0x7f000000)
 331 #define IPV4_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffff0000) == 0xa9fe0000)
 332 #define IPV4_CLASS_DE(a) ((((uint32_t)(a)) & 0xe0000000) == 0xe0000000)
 333 #define IPV4_MC_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffffff00) == 0xe0000000)
 334
 335 /* Max bit/byte length of IPv6 address. */
 336 #define IPV6_MAX_BYTELEN    16
 337 #define IPV6_MAX_BITLEN    128
 338 #define IPV6_MAX_PREFIXLEN 128
 339 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 340 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 341 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 342
 343 /* Count prefix size from mask length */
 344 #define PSIZE(a) (((a) + 7) / (8))
 345
 346 #define BSIZE(a) ((a) * (8))
 347
 348 /* Prefix's family member. */
 349 #define PREFIX_FAMILY(p)  ((p)->family)
 350
 351 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 352 #ifndef s6_addr32
 353 #if defined(SUNOS_5)
 354 /* Some SunOS define s6_addr32 only to kernel */
 355 #define s6_addr32 _S6_un._S6_u32
 356 #else
 357 #define s6_addr32 __u6_addr.__u6_addr32
 358 #endif /* SUNOS_5 */
 359 #endif /*s6_addr32*/
 360
 361 /* Prototypes. */
 362 extern int str2family(const char *);
 363 extern int afi2family(afi_t);
 364 extern afi_t family2afi(int);
 365 extern const char *family2str(int family);
 366 extern const char *safi2str(safi_t safi);
 367 extern const char *afi2str(afi_t afi);
 368
 369 /* Check bit of the prefix. */
 370 extern unsigned int prefix_bit(const uint8_t *prefix, const uint8_t prefixlen);
 371 extern unsigned int prefix6_bit(const struct in6_addr *prefix,
 372                                 const uint8_t prefixlen);
 373
 374 extern struct prefix *prefix_new(void);
 375 extern void prefix_free(struct prefix *);
 376 extern const char *prefix_family_str(const struct prefix *);
 377 extern int prefix_blen(const struct prefix *);
 378 extern int str2prefix(const char *, struct prefix *);
 379
 380 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 381
 382 extern const char *prefix2str(union prefixconstptr, char *, int);
 383 extern int prefix_match(const struct prefix *, const struct prefix *);
 384 extern int prefix_match_network_statement(const struct prefix *,
 385                                           const struct prefix *);
 386 extern int prefix_same(const struct prefix *, const struct prefix *);
 387 extern int prefix_cmp(const struct prefix *, const struct prefix *);
 388 extern int prefix_common_bits(const struct prefix *, const struct prefix *);
 389 extern void prefix_copy(struct prefix *dest, const struct prefix *src);
 390 extern void apply_mask(struct prefix *);
 391
 392 extern struct prefix *sockunion2prefix(const union sockunion *dest,
 393                                        const union sockunion *mask);
 394 extern struct prefix *sockunion2hostprefix(const union sockunion *,
 395                                            struct prefix *p);
 396 extern void prefix2sockunion(const struct prefix *, union sockunion *);
 397
 398 extern int str2prefix_eth(const char *, struct prefix_eth *);
 399
 400 extern struct prefix_ipv4 *prefix_ipv4_new(void);
 401 extern void prefix_ipv4_free(struct prefix_ipv4 *);
 402 extern int str2prefix_ipv4(const char *, struct prefix_ipv4 *);
 403 extern void apply_mask_ipv4(struct prefix_ipv4 *);
 404
 405 #define PREFIX_COPY(DST, SRC)                                                  \
 406         *((struct prefix *)(DST)) = *((const struct prefix *)(SRC))
 407 #define PREFIX_COPY_IPV4(DST, SRC)                                             \
 408         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 409
 410 extern int prefix_ipv4_any(const struct prefix_ipv4 *);
 411 extern void apply_classful_mask_ipv4(struct prefix_ipv4 *);
 412
 413 extern uint8_t ip_masklen(struct in_addr);
 414 extern void masklen2ip(const int, struct in_addr *);
 415 /* returns the network portion of the host address */
 416 extern in_addr_t ipv4_network_addr(in_addr_t hostaddr, int masklen);
 417 /* given the address of a host on a network and the network mask length,
 418  * calculate the broadcast address for that network;
 419  * special treatment for /31: returns the address of the other host
 420  * on the network by flipping the host bit */
 421 extern in_addr_t ipv4_broadcast_addr(in_addr_t hostaddr, int masklen);
 422
 423 extern int netmask_str2prefix_str(const char *, const char *, char *);
 424
 425 extern struct prefix_ipv6 *prefix_ipv6_new(void);
 426 extern void prefix_ipv6_free(struct prefix_ipv6 *);
 427 extern int str2prefix_ipv6(const char *, struct prefix_ipv6 *);
 428 extern void apply_mask_ipv6(struct prefix_ipv6 *);
 429
 430 #define PREFIX_COPY_IPV6(DST, SRC)                                             \
 431         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 432
 433 extern int ip6_masklen(struct in6_addr);
 434 extern void masklen2ip6(const int, struct in6_addr *);
 435
 436 extern const char *inet6_ntoa(struct in6_addr);
 437
 438 extern int is_zero_mac(struct ethaddr *mac);
 439 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 440 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 441
 442 extern unsigned prefix_hash_key(void *pp);
 443
 444 extern int str_to_esi(const char *str, esi_t *esi);
 445 extern char *esi_to_str(const esi_t *esi, char *buf, int size);
 446 extern void prefix_hexdump(const struct prefix *p);
 447 extern void prefix_evpn_hexdump(const struct prefix_evpn *p);
 448
 449 static inline int ipv6_martian(struct in6_addr *addr)
 450 {
 451         struct in6_addr localhost_addr;
 452
 453         inet_pton(AF_INET6, "::1", &localhost_addr);
 454
 455         if (IPV6_ADDR_SAME(&localhost_addr, addr))
 456                 return 1;
 457
 458         return 0;
 459 }
 460
 461 extern int macstr2prefix_evpn(const char *str, struct prefix_evpn *p);
 462
 463 /* NOTE: This routine expects the address argument in network byte order. */
 464 static inline int ipv4_martian(struct in_addr *addr)
 465 {
 466         in_addr_t ip = ntohl(addr->s_addr);
 467
 468         if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 469                 return 1;
 470         }
 471         return 0;
 472 }
 473
 474 static inline int is_default_prefix(const struct prefix *p)
 475 {
 476         if (!p)
 477                 return 0;
 478
 479         if ((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY)
 480             && (p->prefixlen == 0))
 481                 return 1;
 482
 483         if ((p->family == AF_INET6) && (p->prefixlen == 0)
 484             && (!memcmp(&p->u.prefix6, &in6addr_any, sizeof(struct in6_addr))))
 485                 return 1;
 486
 487         return 0;
 488 }
 489
 490 static inline int is_host_route(struct prefix *p)
 491 {
 492         if (p->family == AF_INET)
 493                 return (p->prefixlen == IPV4_MAX_BITLEN);
 494         else if (p->family == AF_INET6)
 495                 return (p->prefixlen == IPV6_MAX_BITLEN);
 496         return 0;
 497 }
 498 #endif /* _ZEBRA_PREFIX_H */