/* $OpenBSD: util.c,v 1.4 2016/01/15 12:41:09 renato Exp $ */ /* * Copyright (c) 2015 Renato Westphal * Copyright (c) 2012 Alexander Bluhm * Copyright (c) 2004 Esben Norby * Copyright (c) 2003, 2004 Henning Brauer * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include "eigrpd.h" #include "log.h" uint8_t mask2prefixlen(in_addr_t ina) { if (ina == 0) return (0); else return (33 - ffs(ntohl(ina))); } uint8_t mask2prefixlen6(struct sockaddr_in6 *sa_in6) { uint8_t l = 0, *ap, *ep; /* * sin6_len is the size of the sockaddr so substract the offset of * the possibly truncated sin6_addr struct. */ ap = (uint8_t *)&sa_in6->sin6_addr; ep = (uint8_t *)sa_in6 + sa_in6->sin6_len; for (; ap < ep; ap++) { /* this "beauty" is adopted from sbin/route/show.c ... */ switch (*ap) { case 0xff: l += 8; break; case 0xfe: l += 7; return (l); case 0xfc: l += 6; return (l); case 0xf8: l += 5; return (l); case 0xf0: l += 4; return (l); case 0xe0: l += 3; return (l); case 0xc0: l += 2; return (l); case 0x80: l += 1; return (l); case 0x00: return (l); default: fatalx("non contiguous inet6 netmask"); } } return (l); } in_addr_t prefixlen2mask(uint8_t prefixlen) { if (prefixlen == 0) return (0); return (htonl(0xffffffff << (32 - prefixlen))); } struct in6_addr * prefixlen2mask6(uint8_t prefixlen) { static struct in6_addr mask; int i; memset(&mask, 0, sizeof(mask)); for (i = 0; i < prefixlen / 8; i++) mask.s6_addr[i] = 0xff; i = prefixlen % 8; if (i) mask.s6_addr[prefixlen / 8] = 0xff00 >> i; return (&mask); } void eigrp_applymask(int af, union eigrpd_addr *dest, const union eigrpd_addr *src, int prefixlen) { struct in6_addr mask; int i; switch (af) { case AF_INET: dest->v4.s_addr = src->v4.s_addr & prefixlen2mask(prefixlen); break; case AF_INET6: memset(&mask, 0, sizeof(mask)); for (i = 0; i < prefixlen / 8; i++) mask.s6_addr[i] = 0xff; i = prefixlen % 8; if (i) mask.s6_addr[prefixlen / 8] = 0xff00 >> i; for (i = 0; i < 16; i++) dest->v6.s6_addr[i] = src->v6.s6_addr[i] & mask.s6_addr[i]; break; default: fatalx("eigrp_applymask: unknown af"); } } int eigrp_addrcmp(int af, const union eigrpd_addr *a, const union eigrpd_addr *b) { switch (af) { case AF_INET: if (a->v4.s_addr != b->v4.s_addr) return (1); break; case AF_INET6: if (!IN6_ARE_ADDR_EQUAL(&a->v6, &b->v6)) return (1); break; default: fatalx("eigrp_addrcmp: unknown af"); } return (0); } int eigrp_addrisset(int af, const union eigrpd_addr *addr) { switch (af) { case AF_UNSPEC: return (0); case AF_INET: if (addr->v4.s_addr != INADDR_ANY) return (1); break; case AF_INET6: if (!IN6_IS_ADDR_UNSPECIFIED(&addr->v6)) return (1); break; default: fatalx("eigrp_addrisset: unknown af"); } return (0); } int eigrp_prefixcmp(int af, const union eigrpd_addr *a, const union eigrpd_addr *b, uint8_t prefixlen) { in_addr_t mask, aa, ba; int i; uint8_t m; switch (af) { case AF_INET: if (prefixlen == 0) return (0); if (prefixlen > 32) fatalx("eigrp_prefixcmp: bad IPv4 prefixlen"); mask = htonl(prefixlen2mask(prefixlen)); aa = htonl(a->v4.s_addr) & mask; ba = htonl(b->v4.s_addr) & mask; return (aa - ba); case AF_INET6: if (prefixlen == 0) return (0); if (prefixlen > 128) fatalx("eigrp_prefixcmp: bad IPv6 prefixlen"); for (i = 0; i < prefixlen / 8; i++) if (a->v6.s6_addr[i] != b->v6.s6_addr[i]) return (a->v6.s6_addr[i] - b->v6.s6_addr[i]); i = prefixlen % 8; if (i) { m = 0xff00 >> i; if ((a->v6.s6_addr[prefixlen / 8] & m) != (b->v6.s6_addr[prefixlen / 8] & m)) return ((a->v6.s6_addr[prefixlen / 8] & m) - (b->v6.s6_addr[prefixlen / 8] & m)); } return (0); default: fatalx("eigrp_prefixcmp: unknown af"); } return (-1); } #define IN6_IS_SCOPE_EMBED(a) \ ((IN6_IS_ADDR_LINKLOCAL(a)) || \ (IN6_IS_ADDR_MC_LINKLOCAL(a)) || \ (IN6_IS_ADDR_MC_INTFACELOCAL(a))) void embedscope(struct sockaddr_in6 *sin6) { uint16_t tmp16; if (IN6_IS_SCOPE_EMBED(&sin6->sin6_addr)) { memcpy(&tmp16, &sin6->sin6_addr.s6_addr[2], sizeof(tmp16)); if (tmp16 != 0) { log_warnx("%s: address %s already has embeded scope %u", __func__, log_sockaddr(sin6), ntohs(tmp16)); } tmp16 = htons(sin6->sin6_scope_id); memcpy(&sin6->sin6_addr.s6_addr[2], &tmp16, sizeof(tmp16)); sin6->sin6_scope_id = 0; } } void recoverscope(struct sockaddr_in6 *sin6) { uint16_t tmp16; if (sin6->sin6_scope_id != 0) { log_warnx("%s: address %s already has scope id %u", __func__, log_sockaddr(sin6), sin6->sin6_scope_id); } if (IN6_IS_SCOPE_EMBED(&sin6->sin6_addr)) { memcpy(&tmp16, &sin6->sin6_addr.s6_addr[2], sizeof(tmp16)); sin6->sin6_scope_id = ntohs(tmp16); sin6->sin6_addr.s6_addr[2] = 0; sin6->sin6_addr.s6_addr[3] = 0; } } void addscope(struct sockaddr_in6 *sin6, uint32_t id) { if (sin6->sin6_scope_id != 0) { log_warnx("%s: address %s already has scope id %u", __func__, log_sockaddr(sin6), sin6->sin6_scope_id); } if (IN6_IS_SCOPE_EMBED(&sin6->sin6_addr)) { sin6->sin6_scope_id = id; } } void clearscope(struct in6_addr *in6) { if (IN6_IS_SCOPE_EMBED(in6)) { in6->s6_addr[2] = 0; in6->s6_addr[3] = 0; } } #undef IN6_IS_SCOPE_EMBED