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 #ifdef __cplusplus
  39 extern "C" {
  40 #endif
  41
  42 #ifndef ETH_ALEN
  43 #define ETH_ALEN 6
  44 #endif
  45
  46 #define ESI_BYTES 10
  47 #define ESI_STR_LEN (3 * ESI_BYTES)
  48
  49 #define ETHER_ADDR_STRLEN (3*ETH_ALEN)
  50 /*
  51  * there isn't a portable ethernet address type. We define our
  52  * own to simplify internal handling
  53  */
  54 struct ethaddr {
  55         uint8_t octet[ETH_ALEN];
  56 } __attribute__((packed));
  57
  58
  59 /* length is the number of valuable bits of prefix structure
  60 * 18 bytes is current length in structure, if address is ipv4
  61 * 30 bytes is in case of ipv6
  62 */
  63 #define PREFIX_LEN_ROUTE_TYPE_5_IPV4 (18*8)
  64 #define PREFIX_LEN_ROUTE_TYPE_5_IPV6 (30*8)
  65
  66 typedef struct esi_t_ {
  67         uint8_t val[10];
  68 } esi_t;
  69
  70 struct evpn_ead_addr {
  71         esi_t esi;
  72         uint32_t eth_tag;
  73 };
  74
  75 struct evpn_macip_addr {
  76         uint32_t eth_tag;
  77         uint8_t ip_prefix_length;
  78         struct ethaddr mac;
  79         struct ipaddr ip;
  80 };
  81
  82 struct evpn_imet_addr {
  83         uint32_t eth_tag;
  84         uint8_t ip_prefix_length;
  85         struct ipaddr ip;
  86 };
  87
  88 struct evpn_es_addr {
  89         esi_t esi;
  90         uint8_t ip_prefix_length;
  91         struct ipaddr ip;
  92 };
  93
  94 struct evpn_prefix_addr {
  95         uint32_t eth_tag;
  96         uint8_t ip_prefix_length;
  97         struct ipaddr ip;
  98 };
  99
 100 /* EVPN address (RFC 7432) */
 101 struct evpn_addr {
 102         uint8_t route_type;
 103         union {
 104                 struct evpn_ead_addr _ead_addr;
 105                 struct evpn_macip_addr _macip_addr;
 106                 struct evpn_imet_addr _imet_addr;
 107                 struct evpn_es_addr _es_addr;
 108                 struct evpn_prefix_addr _prefix_addr;
 109         } u;
 110 #define ead_addr u._ead_addr
 111 #define macip_addr u._macip_addr
 112 #define imet_addr u._imet_addr
 113 #define es_addr u._es_addr
 114 #define prefix_addr u._prefix_addr
 115 };
 116
 117 /*
 118  * A struct prefix contains an address family, a prefix length, and an
 119  * address.  This can represent either a 'network prefix' as defined
 120  * by CIDR, where the 'host bits' of the prefix are 0
 121  * (e.g. AF_INET:10.0.0.0/8), or an address and netmask
 122  * (e.g. AF_INET:10.0.0.9/8), such as might be configured on an
 123  * interface.
 124  */
 125
 126 /* different OSes use different names */
 127 #if defined(AF_PACKET)
 128 #define AF_ETHERNET AF_PACKET
 129 #else
 130 #if defined(AF_LINK)
 131 #define AF_ETHERNET AF_LINK
 132 #endif
 133 #endif
 134
 135 /* The 'family' in the prefix structure is internal to FRR and need not
 136  * map to standard OS AF_ definitions except where needed for interacting
 137  * with the kernel. However, AF_ definitions are currently in use and
 138  * prevalent across the code. Define a new FRR-specific AF for EVPN to
 139  * distinguish between 'ethernet' (MAC-only) and 'evpn' prefixes and
 140  * ensure it does not conflict with any OS AF_ definition.
 141  */
 142 #if !defined(AF_EVPN)
 143 #define AF_EVPN (AF_MAX + 1)
 144 #endif
 145
 146 #if !defined(AF_FLOWSPEC)
 147 #define AF_FLOWSPEC (AF_MAX + 2)
 148 #endif
 149
 150 struct flowspec_prefix {
 151         uint16_t prefixlen; /* length in bytes */
 152         uintptr_t ptr;
 153 };
 154
 155 /* FRR generic prefix structure. */
 156 struct prefix {
 157         uint8_t family;
 158         uint16_t prefixlen;
 159         union {
 160                 uint8_t prefix;
 161                 struct in_addr prefix4;
 162                 struct in6_addr prefix6;
 163                 struct {
 164                         struct in_addr id;
 165                         struct in_addr adv_router;
 166                 } lp;
 167                 struct ethaddr prefix_eth; /* AF_ETHERNET */
 168                 uint8_t val[16];
 169                 uint32_t val32[4];
 170                 uintptr_t ptr;
 171                 struct evpn_addr prefix_evpn; /* AF_EVPN */
 172                 struct flowspec_prefix prefix_flowspec; /* AF_FLOWSPEC */
 173         } u __attribute__((aligned(8)));
 174 };
 175
 176 /* IPv4 prefix structure. */
 177 struct prefix_ipv4 {
 178         uint8_t family;
 179         uint16_t prefixlen;
 180         struct in_addr prefix __attribute__((aligned(8)));
 181 };
 182
 183 /* IPv6 prefix structure. */
 184 struct prefix_ipv6 {
 185         uint8_t family;
 186         uint16_t prefixlen;
 187         struct in6_addr prefix __attribute__((aligned(8)));
 188 };
 189
 190 struct prefix_ls {
 191         uint8_t family;
 192         uint16_t prefixlen;
 193         struct in_addr id __attribute__((aligned(8)));
 194         struct in_addr adv_router;
 195 };
 196
 197 /* Prefix for routing distinguisher. */
 198 struct prefix_rd {
 199         uint8_t family;
 200         uint16_t prefixlen;
 201         uint8_t val[8] __attribute__((aligned(8)));
 202 };
 203
 204 /* Prefix for ethernet. */
 205 struct prefix_eth {
 206         uint8_t family;
 207         uint16_t prefixlen;
 208         struct ethaddr eth_addr __attribute__((aligned(8))); /* AF_ETHERNET */
 209 };
 210
 211 /* EVPN prefix structure. */
 212 struct prefix_evpn {
 213         uint8_t family;
 214         uint16_t prefixlen;
 215         struct evpn_addr prefix __attribute__((aligned(8)));
 216 };
 217
 218 static inline int is_evpn_prefix_ipaddr_none(const struct prefix_evpn *evp)
 219 {
 220         if (evp->prefix.route_type == 2)
 221                 return IS_IPADDR_NONE(&(evp)->prefix.macip_addr.ip);
 222         if (evp->prefix.route_type == 3)
 223                 return IS_IPADDR_NONE(&(evp)->prefix.imet_addr.ip);
 224         if (evp->prefix.route_type == 4)
 225                 return IS_IPADDR_NONE(&(evp)->prefix.es_addr.ip);
 226         if (evp->prefix.route_type == 5)
 227                 return IS_IPADDR_NONE(&(evp)->prefix.prefix_addr.ip);
 228         return 0;
 229 }
 230
 231 static inline int is_evpn_prefix_ipaddr_v4(const struct prefix_evpn *evp)
 232 {
 233         if (evp->prefix.route_type == 2)
 234                 return IS_IPADDR_V4(&(evp)->prefix.macip_addr.ip);
 235         if (evp->prefix.route_type == 3)
 236                 return IS_IPADDR_V4(&(evp)->prefix.imet_addr.ip);
 237         if (evp->prefix.route_type == 4)
 238                 return IS_IPADDR_V4(&(evp)->prefix.es_addr.ip);
 239         if (evp->prefix.route_type == 5)
 240                 return IS_IPADDR_V4(&(evp)->prefix.prefix_addr.ip);
 241         return 0;
 242 }
 243
 244 static inline int is_evpn_prefix_ipaddr_v6(const struct prefix_evpn *evp)
 245 {
 246         if (evp->prefix.route_type == 2)
 247                 return IS_IPADDR_V6(&(evp)->prefix.macip_addr.ip);
 248         if (evp->prefix.route_type == 3)
 249                 return IS_IPADDR_V6(&(evp)->prefix.imet_addr.ip);
 250         if (evp->prefix.route_type == 4)
 251                 return IS_IPADDR_V6(&(evp)->prefix.es_addr.ip);
 252         if (evp->prefix.route_type == 5)
 253                 return IS_IPADDR_V6(&(evp)->prefix.prefix_addr.ip);
 254         return 0;
 255 }
 256
 257 /* Prefix for a generic pointer */
 258 struct prefix_ptr {
 259         uint8_t family;
 260         uint16_t prefixlen;
 261         uintptr_t prefix __attribute__((aligned(8)));
 262 };
 263
 264 /* Prefix for a Flowspec entry */
 265 struct prefix_fs {
 266         uint8_t family;
 267         uint16_t prefixlen; /* unused */
 268         struct flowspec_prefix  prefix __attribute__((aligned(8)));
 269 };
 270
 271 struct prefix_sg {
 272         uint8_t family;
 273         uint16_t prefixlen;
 274         struct in_addr src __attribute__((aligned(8)));
 275         struct in_addr grp;
 276 };
 277
 278 /* helper to get type safety/avoid casts on calls
 279  * (w/o this, functions accepting all prefix types need casts on the caller
 280  * side, which strips type safety since the cast will accept any pointer
 281  * type.)
 282  */
 283 #ifndef __cplusplus
 284 #define prefixtype(uname, typename, fieldname) \
 285         typename *fieldname;
 286 #else
 287 #define prefixtype(uname, typename, fieldname) \
 288         typename *fieldname; \
 289         uname(typename *x) { this->fieldname = x; }
 290 #endif
 291
 292 union prefixptr {
 293         prefixtype(prefixptr, struct prefix,      p)
 294         prefixtype(prefixptr, struct prefix_ipv4, p4)
 295         prefixtype(prefixptr, struct prefix_ipv6, p6)
 296         prefixtype(prefixptr, struct prefix_evpn, evp)
 297         prefixtype(prefixptr, struct prefix_fs,   fs)
 298 } __attribute__((transparent_union));
 299
 300 union prefixconstptr {
 301         prefixtype(prefixconstptr, const struct prefix,      p)
 302         prefixtype(prefixconstptr, const struct prefix_ipv4, p4)
 303         prefixtype(prefixconstptr, const struct prefix_ipv6, p6)
 304         prefixtype(prefixconstptr, const struct prefix_evpn, evp)
 305         prefixtype(prefixconstptr, const struct prefix_fs,   fs)
 306 } __attribute__((transparent_union));
 307
 308 #ifndef INET_ADDRSTRLEN
 309 #define INET_ADDRSTRLEN 16
 310 #endif /* INET_ADDRSTRLEN */
 311
 312 #ifndef INET6_ADDRSTRLEN
 313 /* dead:beef:dead:beef:dead:beef:dead:beef + \0 */
 314 #define INET6_ADDRSTRLEN 46
 315 #endif /* INET6_ADDRSTRLEN */
 316
 317 #ifndef INET6_BUFSIZ
 318 #define INET6_BUFSIZ 53
 319 #endif /* INET6_BUFSIZ */
 320
 321 /* Maximum string length of the result of prefix2str */
 322 #define PREFIX_STRLEN 80
 323
 324 /*
 325  * Longest possible length of a (S,G) string is 36 bytes
 326  * 123.123.123.123 = 15 * 2
 327  * (,) = 3
 328  * NULL Character at end = 1
 329  * (123.123.123.123,123.123.123.123)
 330  */
 331 #define PREFIX_SG_STR_LEN 34
 332
 333 /* Max bit/byte length of IPv4 address. */
 334 #define IPV4_MAX_BYTELEN    4
 335 #define IPV4_MAX_BITLEN    32
 336 #define IPV4_MAX_PREFIXLEN 32
 337 #define IPV4_ADDR_CMP(D,S)   memcmp ((D), (S), IPV4_MAX_BYTELEN)
 338
 339 static inline bool ipv4_addr_same(const struct in_addr *a,
 340                                   const struct in_addr *b)
 341 {
 342         return (a->s_addr == b->s_addr);
 343 }
 344 #define IPV4_ADDR_SAME(A,B)  ipv4_addr_same((A), (B))
 345
 346 static inline void ipv4_addr_copy(struct in_addr *dst,
 347                                   const struct in_addr *src)
 348 {
 349         dst->s_addr = src->s_addr;
 350 }
 351 #define IPV4_ADDR_COPY(D,S)  ipv4_addr_copy((D), (S))
 352
 353 #define IPV4_NET0(a) ((((uint32_t)(a)) & 0xff000000) == 0x00000000)
 354 #define IPV4_NET127(a) ((((uint32_t)(a)) & 0xff000000) == 0x7f000000)
 355 #define IPV4_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffff0000) == 0xa9fe0000)
 356 #define IPV4_CLASS_DE(a) ((((uint32_t)(a)) & 0xe0000000) == 0xe0000000)
 357 #define IPV4_MC_LINKLOCAL(a) ((((uint32_t)(a)) & 0xffffff00) == 0xe0000000)
 358
 359 /* Max bit/byte length of IPv6 address. */
 360 #define IPV6_MAX_BYTELEN    16
 361 #define IPV6_MAX_BITLEN    128
 362 #define IPV6_MAX_PREFIXLEN 128
 363 #define IPV6_ADDR_CMP(D,S)   memcmp ((D), (S), IPV6_MAX_BYTELEN)
 364 #define IPV6_ADDR_SAME(D,S)  (memcmp ((D), (S), IPV6_MAX_BYTELEN) == 0)
 365 #define IPV6_ADDR_COPY(D,S)  memcpy ((D), (S), IPV6_MAX_BYTELEN)
 366
 367 /* Count prefix size from mask length */
 368 #define PSIZE(a) (((a) + 7) / (8))
 369
 370 #define BSIZE(a) ((a) * (8))
 371
 372 /* Prefix's family member. */
 373 #define PREFIX_FAMILY(p)  ((p)->family)
 374
 375 /* glibc defines s6_addr32 to __in6_u.__u6_addr32 if __USE_{MISC || GNU} */
 376 #ifndef s6_addr32
 377 #if defined(SUNOS_5)
 378 /* Some SunOS define s6_addr32 only to kernel */
 379 #define s6_addr32 _S6_un._S6_u32
 380 #else
 381 #define s6_addr32 __u6_addr.__u6_addr32
 382 #endif /* SUNOS_5 */
 383 #endif /*s6_addr32*/
 384
 385 /* Prototypes. */
 386 extern int str2family(const char *);
 387 extern int afi2family(afi_t);
 388 extern afi_t family2afi(int);
 389 extern const char *family2str(int family);
 390 extern const char *safi2str(safi_t safi);
 391 extern const char *afi2str(afi_t afi);
 392
 393 /* Check bit of the prefix. */
 394 extern unsigned int prefix_bit(const uint8_t *prefix, const uint16_t prefixlen);
 395
 396 extern struct prefix *prefix_new(void);
 397 extern void prefix_free(struct prefix **p);
 398 /*
 399  * Function to handle prefix_free being used as a del function.
 400  */
 401 extern void prefix_free_lists(void *arg);
 402 extern const char *prefix_family_str(const struct prefix *);
 403 extern int prefix_blen(const struct prefix *);
 404 extern int str2prefix(const char *, struct prefix *);
 405
 406 #define PREFIX2STR_BUFFER  PREFIX_STRLEN
 407
 408 extern void prefix_mcast_inet4_dump(const char *onfail, struct in_addr addr,
 409                                 char *buf, int buf_size);
 410 extern const char *prefix_sg2str(const struct prefix_sg *sg, char *str);
 411 extern const char *prefix2str(union prefixconstptr, char *, int);
 412 extern int evpn_type5_prefix_match(const struct prefix *evpn_pfx,
 413                                    const struct prefix *match_pfx);
 414 extern int prefix_match(const struct prefix *, const struct prefix *);
 415 extern int prefix_match_network_statement(const struct prefix *,
 416                                           const struct prefix *);
 417 extern int prefix_same(union prefixconstptr, union prefixconstptr);
 418 extern int prefix_cmp(union prefixconstptr, union prefixconstptr);
 419 extern int prefix_common_bits(const struct prefix *, const struct prefix *);
 420 extern void prefix_copy(union prefixptr, union prefixconstptr);
 421 extern void apply_mask(struct prefix *);
 422
 423 #ifdef __clang_analyzer__
 424 /* clang-SA doesn't understand transparent unions, making it think that the
 425  * target of prefix_copy is uninitialized.  So just memset the target.
 426  * cf. https://bugs.llvm.org/show_bug.cgi?id=42811
 427  */
 428 #define prefix_copy(a, b) ({ memset(a, 0, sizeof(*a)); prefix_copy(a, b); })
 429 #endif
 430
 431 extern struct prefix *sockunion2hostprefix(const union sockunion *,
 432                                            struct prefix *p);
 433 extern void prefix2sockunion(const struct prefix *, union sockunion *);
 434
 435 extern int str2prefix_eth(const char *, struct prefix_eth *);
 436
 437 extern struct prefix_ipv4 *prefix_ipv4_new(void);
 438 extern void prefix_ipv4_free(struct prefix_ipv4 **p);
 439 extern int str2prefix_ipv4(const char *, struct prefix_ipv4 *);
 440 extern void apply_mask_ipv4(struct prefix_ipv4 *);
 441
 442 #define PREFIX_COPY(DST, SRC)                                                  \
 443         *((struct prefix *)(DST)) = *((const struct prefix *)(SRC))
 444 #define PREFIX_COPY_IPV4(DST, SRC)                                             \
 445         *((struct prefix_ipv4 *)(DST)) = *((const struct prefix_ipv4 *)(SRC));
 446
 447 extern int prefix_ipv4_any(const struct prefix_ipv4 *);
 448 extern void apply_classful_mask_ipv4(struct prefix_ipv4 *);
 449
 450 extern uint8_t ip_masklen(struct in_addr);
 451 extern void masklen2ip(const int, struct in_addr *);
 452 /* given the address of a host on a network and the network mask length,
 453  * calculate the broadcast address for that network;
 454  * special treatment for /31 according to RFC3021 section 3.3 */
 455 extern in_addr_t ipv4_broadcast_addr(in_addr_t hostaddr, int masklen);
 456
 457 extern int netmask_str2prefix_str(const char *, const char *, char *);
 458
 459 extern struct prefix_ipv6 *prefix_ipv6_new(void);
 460 extern void prefix_ipv6_free(struct prefix_ipv6 **p);
 461 extern int str2prefix_ipv6(const char *, struct prefix_ipv6 *);
 462 extern void apply_mask_ipv6(struct prefix_ipv6 *);
 463
 464 #define PREFIX_COPY_IPV6(DST, SRC)                                             \
 465         *((struct prefix_ipv6 *)(DST)) = *((const struct prefix_ipv6 *)(SRC));
 466
 467 extern int ip6_masklen(struct in6_addr);
 468 extern void masklen2ip6(const int, struct in6_addr *);
 469
 470 extern const char *inet6_ntoa(struct in6_addr);
 471
 472 extern int is_zero_mac(const struct ethaddr *mac);
 473 extern bool is_mcast_mac(const struct ethaddr *mac);
 474 extern bool is_bcast_mac(const struct ethaddr *mac);
 475 extern int prefix_str2mac(const char *str, struct ethaddr *mac);
 476 extern char *prefix_mac2str(const struct ethaddr *mac, char *buf, int size);
 477
 478 extern unsigned prefix_hash_key(const void *pp);
 479
 480 extern int str_to_esi(const char *str, esi_t *esi);
 481 extern char *esi_to_str(const esi_t *esi, char *buf, int size);
 482 extern void prefix_evpn_hexdump(const struct prefix_evpn *p);
 483
 484 static inline int ipv6_martian(struct in6_addr *addr)
 485 {
 486         struct in6_addr localhost_addr;
 487
 488         inet_pton(AF_INET6, "::1", &localhost_addr);
 489
 490         if (IPV6_ADDR_SAME(&localhost_addr, addr))
 491                 return 1;
 492
 493         return 0;
 494 }
 495
 496 extern int macstr2prefix_evpn(const char *str, struct prefix_evpn *p);
 497
 498 /* NOTE: This routine expects the address argument in network byte order. */
 499 static inline int ipv4_martian(struct in_addr *addr)
 500 {
 501         in_addr_t ip = ntohl(addr->s_addr);
 502
 503         if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
 504                 return 1;
 505         }
 506         return 0;
 507 }
 508
 509 static inline int is_default_prefix(const struct prefix *p)
 510 {
 511         if (!p)
 512                 return 0;
 513
 514         if ((p->family == AF_INET) && (p->u.prefix4.s_addr == INADDR_ANY)
 515             && (p->prefixlen == 0))
 516                 return 1;
 517
 518         if ((p->family == AF_INET6) && (p->prefixlen == 0)
 519             && (!memcmp(&p->u.prefix6, &in6addr_any, sizeof(struct in6_addr))))
 520                 return 1;
 521
 522         return 0;
 523 }
 524
 525 static inline int is_host_route(struct prefix *p)
 526 {
 527         if (p->family == AF_INET)
 528                 return (p->prefixlen == IPV4_MAX_BITLEN);
 529         else if (p->family == AF_INET6)
 530                 return (p->prefixlen == IPV6_MAX_BITLEN);
 531         return 0;
 532 }
 533
 534 static inline int is_default_host_route(struct prefix *p)
 535 {
 536         if (p->family == AF_INET) {
 537                 return (p->u.prefix4.s_addr == INADDR_ANY &&
 538                         p->prefixlen == IPV4_MAX_BITLEN);
 539         } else if (p->family == AF_INET6) {
 540                 return ((!memcmp(&p->u.prefix6, &in6addr_any,
 541                                  sizeof(struct in6_addr))) &&
 542                         p->prefixlen == IPV6_MAX_BITLEN);
 543         }
 544         return 0;
 545 }
 546
 547 #ifdef __cplusplus
 548 }
 549 #endif
 550
 551 #endif /* _ZEBRA_PREFIX_H */