Edit
IABSD.fr/src/usr.sbin/eigrpd/util.c
jmc
- usr.sbin/eigrpd/util.c
-
/* $OpenBSD: util.c,v 1.12 2022/12/28 21:30:16 jmc Exp $ */ /* * Copyright (c) 2015 Renato Westphal <renato@openbsd.org> * Copyright (c) 2012 Alexander Bluhm <bluhm@openbsd.org> * Copyright (c) 2004 Esben Norby <norby@openbsd.org> * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> * * 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 <sys/types.h> #include <string.h> #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) { unsigned int l = 0; uint8_t *ap, *ep; /* * sin6_len is the size of the sockaddr so subtract 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; goto done; case 0xfc: l += 6; goto done; case 0xf8: l += 5; goto done; case 0xf0: l += 4; goto done; case 0xe0: l += 3; goto done; case 0xc0: l += 2; goto done; case 0x80: l += 1; goto done; case 0x00: goto done; default: fatalx("non contiguous inet6 netmask"); } } done: if (l > sizeof(struct in6_addr) * 8) fatalx("inet6 prefixlen out of bound"); 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 (0); return ((ntohl(a->v4.s_addr) > ntohl(b->v4.s_addr)) ? 1 : -1); case AF_INET6: return (!!memcmp(&a->v6, &b->v6, sizeof(struct in6_addr))); default: fatalx("eigrp_addrcmp: unknown af"); } } 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); } int bad_addr_v4(struct in_addr addr) { uint32_t a = ntohl(addr.s_addr); if (((a >> IN_CLASSA_NSHIFT) == 0) || ((a >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) || IN_MULTICAST(a)) return (1); return (0); } int bad_addr_v6(struct in6_addr *addr) { if (IN6_IS_ADDR_UNSPECIFIED(addr) || IN6_IS_ADDR_LOOPBACK(addr) || IN6_IS_ADDR_MULTICAST(addr) || IN6_IS_ADDR_SITELOCAL(addr) || IN6_IS_ADDR_V4MAPPED(addr) || IN6_IS_ADDR_V4COMPAT(addr)) return (1); return (0); } int bad_addr(int af, union eigrpd_addr *addr) { switch (af) { case AF_INET: return (bad_addr_v4(addr->v4)); case AF_INET6: return (bad_addr_v6(&addr->v6)); default: fatalx("bad_addr: unknown af"); } } 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 embedded 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; } } void sa2addr(struct sockaddr *sa, int *af, union eigrpd_addr *addr) { struct sockaddr_in *sa_in = (struct sockaddr_in *)sa; struct sockaddr_in6 *sa_in6 = (struct sockaddr_in6 *)sa; memset(addr, 0, sizeof(*addr)); switch (sa->sa_family) { case AF_INET: *af = AF_INET; addr->v4 = sa_in->sin_addr; break; case AF_INET6: *af = AF_INET6; addr->v6 = sa_in6->sin6_addr; break; default: fatalx("sa2addr: unknown af"); } }