Index: head/lib/libc/net/getaddrinfo.c =================================================================== --- head/lib/libc/net/getaddrinfo.c (revision 145112) +++ head/lib/libc/net/getaddrinfo.c (revision 145113) @@ -1,2589 +1,2590 @@ /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator. * * Issues to be discussed: * - Thread safe-ness must be checked. * - Return values. There are nonstandard return values defined and used * in the source code. This is because RFC2553 is silent about which error * code must be returned for which situation. * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is * invalid. current code - SEGV on freeaddrinfo(NULL) * * Note: * - The code filters out AFs that are not supported by the kernel, * when globbing NULL hostname (to loopback, or wildcard). Is it the right * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG * in ai_flags? * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague. * (1) what should we do against numeric hostname (2) what should we do * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready? * non-loopback address configured? global address configured? * * OS specific notes for netbsd/openbsd/freebsd4/bsdi4: * - To avoid search order issue, we have a big amount of code duplicate * from gethnamaddr.c and some other places. The issues that there's no * lower layer function to lookup "IPv4 or IPv6" record. Calling * gethostbyname2 from getaddrinfo will end up in wrong search order, as * presented above. * * OS specific notes for freebsd4: * - FreeBSD supported $GAI. The code does not. * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not. */ #include __FBSDID("$FreeBSD$"); #include "namespace.h" #include "reentrant.h" #include #include #include #include #include #include #ifdef INET6 #include #include #include #include /* XXX */ #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "res_config.h" #ifdef DEBUG #include #endif #include #include #include "un-namespace.h" #include "libc_private.h" #if defined(__KAME__) && defined(INET6) # define FAITH #endif #define SUCCESS 0 #define ANY 0 #define YES 1 #define NO 0 static const char in_addrany[] = { 0, 0, 0, 0 }; static const char in_loopback[] = { 127, 0, 0, 1 }; #ifdef INET6 static const char in6_addrany[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; static const char in6_loopback[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; #endif struct policyqueue { TAILQ_ENTRY(policyqueue) pc_entry; #ifdef INET6 struct in6_addrpolicy pc_policy; #endif }; TAILQ_HEAD(policyhead, policyqueue); static const struct afd { int a_af; int a_addrlen; int a_socklen; int a_off; const char *a_addrany; const char *a_loopback; int a_scoped; } afdl [] = { #ifdef INET6 #define N_INET6 0 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), offsetof(struct sockaddr_in6, sin6_addr), in6_addrany, in6_loopback, 1}, #define N_INET 1 #else #define N_INET 0 #endif {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), offsetof(struct sockaddr_in, sin_addr), in_addrany, in_loopback, 0}, {0, 0, 0, 0, NULL, NULL, 0}, }; struct explore { int e_af; int e_socktype; int e_protocol; const char *e_protostr; int e_wild; #define WILD_AF(ex) ((ex)->e_wild & 0x01) #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02) #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04) }; static const struct explore explore[] = { #if 0 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 }, #endif #ifdef INET6 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 }, #endif { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, { PF_INET, SOCK_RAW, ANY, NULL, 0x05 }, { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 }, { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 }, { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 }, { -1, 0, 0, NULL, 0 }, }; #ifdef INET6 #define PTON_MAX 16 #else #define PTON_MAX 4 #endif #define AIO_SRCFLAG_DEPRECATED 0x1 struct ai_order { union { struct sockaddr_storage aiou_ss; struct sockaddr aiou_sa; } aio_src_un; #define aio_srcsa aio_src_un.aiou_sa u_int32_t aio_srcflag; int aio_srcscope; int aio_dstscope; struct policyqueue *aio_srcpolicy; struct policyqueue *aio_dstpolicy; struct addrinfo *aio_ai; int aio_matchlen; }; static const ns_src default_dns_files[] = { { NSSRC_FILES, NS_SUCCESS }, { NSSRC_DNS, NS_SUCCESS }, { 0 } }; struct res_target { struct res_target *next; const char *name; /* domain name */ int qclass, qtype; /* class and type of query */ u_char *answer; /* buffer to put answer */ int anslen; /* size of answer buffer */ int n; /* result length */ }; #define MAXPACKET (64*1024) typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; static int str2number(const char *); static int explore_null(const struct addrinfo *, const char *, struct addrinfo **); static int explore_numeric(const struct addrinfo *, const char *, const char *, struct addrinfo **, const char *); static int explore_numeric_scope(const struct addrinfo *, const char *, const char *, struct addrinfo **); static int get_canonname(const struct addrinfo *, struct addrinfo *, const char *); static struct addrinfo *get_ai(const struct addrinfo *, const struct afd *, const char *); static int get_portmatch(const struct addrinfo *, const char *); static int get_port(struct addrinfo *, const char *, int); static const struct afd *find_afd(int); static int addrconfig(struct addrinfo *); static void set_source(struct ai_order *, struct policyhead *); static int comp_dst(const void *, const void *); #ifdef INET6 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *); #endif static int gai_addr2scopetype(struct sockaddr *); static int explore_fqdn(const struct addrinfo *, const char *, const char *, struct addrinfo **); static int reorder(struct addrinfo *); static int get_addrselectpolicy(struct policyhead *); static void free_addrselectpolicy(struct policyhead *); static struct policyqueue *match_addrselectpolicy(struct sockaddr *, struct policyhead *); static int matchlen(struct sockaddr *, struct sockaddr *); static struct addrinfo *getanswer(const querybuf *, int, const char *, int, const struct addrinfo *); #if defined(RESOLVSORT) static int addr4sort(struct addrinfo *); #endif static int _dns_getaddrinfo(void *, void *, va_list); static void _sethtent(FILE **); static void _endhtent(FILE **); static struct addrinfo *_gethtent(FILE **, const char *, const struct addrinfo *); static int _files_getaddrinfo(void *, void *, va_list); #ifdef YP static struct addrinfo *_yphostent(char *, const struct addrinfo *); static int _yp_getaddrinfo(void *, void *, va_list); #endif static int res_queryN(const char *, struct res_target *); static int res_searchN(const char *, struct res_target *); static int res_querydomainN(const char *, const char *, struct res_target *); /* * XXX: Many dependencies are not thread-safe. Still, we cannot use * getaddrinfo() in conjunction with other functions which call them. */ static mutex_t _getaddrinfo_thread_lock = MUTEX_INITIALIZER; #define THREAD_LOCK() mutex_lock(&_getaddrinfo_thread_lock); #define THREAD_UNLOCK() mutex_unlock(&_getaddrinfo_thread_lock); /* XXX macros that make external reference is BAD. */ #define GET_AI(ai, afd, addr) \ do { \ /* external reference: pai, error, and label free */ \ (ai) = get_ai(pai, (afd), (addr)); \ if ((ai) == NULL) { \ error = EAI_MEMORY; \ goto free; \ } \ } while (/*CONSTCOND*/0) #define GET_PORT(ai, serv) \ do { \ /* external reference: error and label free */ \ error = get_port((ai), (serv), 0); \ if (error != 0) \ goto free; \ } while (/*CONSTCOND*/0) #define GET_CANONNAME(ai, str) \ do { \ /* external reference: pai, error and label free */ \ error = get_canonname(pai, (ai), (str)); \ if (error != 0) \ goto free; \ } while (/*CONSTCOND*/0) #define ERR(err) \ do { \ /* external reference: error, and label bad */ \ error = (err); \ goto bad; \ /*NOTREACHED*/ \ } while (/*CONSTCOND*/0) #define MATCH_FAMILY(x, y, w) \ ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC))) #define MATCH(x, y, w) \ ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY))) void freeaddrinfo(ai) struct addrinfo *ai; { struct addrinfo *next; do { next = ai->ai_next; if (ai->ai_canonname) free(ai->ai_canonname); /* no need to free(ai->ai_addr) */ free(ai); ai = next; } while (ai); } static int str2number(p) const char *p; { char *ep; unsigned long v; if (*p == '\0') return -1; ep = NULL; errno = 0; v = strtoul(p, &ep, 10); if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) return v; else return -1; } int getaddrinfo(hostname, servname, hints, res) const char *hostname, *servname; const struct addrinfo *hints; struct addrinfo **res; { struct addrinfo sentinel; struct addrinfo *cur; int error = 0; struct addrinfo ai; struct addrinfo ai0; struct addrinfo *pai; const struct explore *ex; int numeric = 0; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; pai = &ai; pai->ai_flags = 0; pai->ai_family = PF_UNSPEC; pai->ai_socktype = ANY; pai->ai_protocol = ANY; pai->ai_addrlen = 0; pai->ai_canonname = NULL; pai->ai_addr = NULL; pai->ai_next = NULL; if (hostname == NULL && servname == NULL) return EAI_NONAME; if (hints) { /* error check for hints */ if (hints->ai_addrlen || hints->ai_canonname || hints->ai_addr || hints->ai_next) ERR(EAI_BADHINTS); /* xxx */ if (hints->ai_flags & ~AI_MASK) ERR(EAI_BADFLAGS); switch (hints->ai_family) { case PF_UNSPEC: case PF_INET: #ifdef INET6 case PF_INET6: #endif break; default: ERR(EAI_FAMILY); } memcpy(pai, hints, sizeof(*pai)); /* * if both socktype/protocol are specified, check if they * are meaningful combination. */ if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) { for (ex = explore; ex->e_af >= 0; ex++) { if (pai->ai_family != ex->e_af) continue; if (ex->e_socktype == ANY) continue; if (ex->e_protocol == ANY) continue; if (pai->ai_socktype == ex->e_socktype && pai->ai_protocol != ex->e_protocol) { ERR(EAI_BADHINTS); } } } } /* * post-2553: AI_ALL and AI_V4MAPPED are effective only against * AF_INET6 query. They need to be ignored if specified in other * occassions. */ switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) { case AI_V4MAPPED: case AI_ALL | AI_V4MAPPED: if (pai->ai_family != AF_INET6) pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); break; case AI_ALL: #if 1 /* illegal */ ERR(EAI_BADFLAGS); #else pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED); #endif break; } /* * check for special cases. (1) numeric servname is disallowed if * socktype/protocol are left unspecified. (2) servname is disallowed * for raw and other inet{,6} sockets. */ if (MATCH_FAMILY(pai->ai_family, PF_INET, 1) #ifdef PF_INET6 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1) #endif ) { ai0 = *pai; /* backup *pai */ if (pai->ai_family == PF_UNSPEC) { #ifdef PF_INET6 pai->ai_family = PF_INET6; #else pai->ai_family = PF_INET; #endif } error = get_portmatch(pai, servname); if (error) ERR(error); *pai = ai0; } ai0 = *pai; /* NULL hostname, or numeric hostname */ for (ex = explore; ex->e_af >= 0; ex++) { *pai = ai0; /* PF_UNSPEC entries are prepared for DNS queries only */ if (ex->e_af == PF_UNSPEC) continue; if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex))) continue; if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) continue; if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) continue; if (pai->ai_family == PF_UNSPEC) pai->ai_family = ex->e_af; if (pai->ai_socktype == ANY && ex->e_socktype != ANY) pai->ai_socktype = ex->e_socktype; if (pai->ai_protocol == ANY && ex->e_protocol != ANY) pai->ai_protocol = ex->e_protocol; if (hostname == NULL) error = explore_null(pai, servname, &cur->ai_next); else error = explore_numeric_scope(pai, hostname, servname, &cur->ai_next); if (error) goto free; while (cur && cur->ai_next) cur = cur->ai_next; } /* * XXX * If numreic representation of AF1 can be interpreted as FQDN * representation of AF2, we need to think again about the code below. */ if (sentinel.ai_next) { numeric = 1; goto good; } if (hostname == NULL) ERR(EAI_NONAME); /* used to be EAI_NODATA */ if (pai->ai_flags & AI_NUMERICHOST) ERR(EAI_NONAME); if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0)) ERR(EAI_FAIL); /* * hostname as alphabetical name. * we would like to prefer AF_INET6 than AF_INET, so we'll make a * outer loop by AFs. */ for (ex = explore; ex->e_af >= 0; ex++) { *pai = ai0; /* require exact match for family field */ if (pai->ai_family != ex->e_af) continue; if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) { continue; } if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) { continue; } if (pai->ai_socktype == ANY && ex->e_socktype != ANY) pai->ai_socktype = ex->e_socktype; if (pai->ai_protocol == ANY && ex->e_protocol != ANY) pai->ai_protocol = ex->e_protocol; error = explore_fqdn(pai, hostname, servname, &cur->ai_next); while (cur && cur->ai_next) cur = cur->ai_next; } /* XXX inhibit errors if we have the result */ if (sentinel.ai_next) error = 0; good: /* * ensure we return either: * - error == 0, non-NULL *res * - error != 0, NULL *res */ if (error == 0) { if (sentinel.ai_next) { /* * If the returned entry is for an active connection, * and the given name is not numeric, reorder the * list, so that the application would try the list * in the most efficient order. */ if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) { if (!numeric) (void)reorder(&sentinel); } *res = sentinel.ai_next; return SUCCESS; } else error = EAI_FAIL; } free: bad: if (sentinel.ai_next) freeaddrinfo(sentinel.ai_next); *res = NULL; return error; } static int reorder(sentinel) struct addrinfo *sentinel; { struct addrinfo *ai, **aip; struct ai_order *aio; int i, n; struct policyhead policyhead; /* count the number of addrinfo elements for sorting. */ for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++) ; /* * If the number is small enough, we can skip the reordering process. */ if (n <= 1) return(n); /* allocate a temporary array for sort and initialization of it. */ if ((aio = malloc(sizeof(*aio) * n)) == NULL) return(n); /* give up reordering */ memset(aio, 0, sizeof(*aio) * n); /* retrieve address selection policy from the kernel */ TAILQ_INIT(&policyhead); if (!get_addrselectpolicy(&policyhead)) { /* no policy is installed into kernel, we don't sort. */ free(aio); return (n); } for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) { aio[i].aio_ai = ai; aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr); aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr, &policyhead); set_source(&aio[i], &policyhead); } /* perform sorting. */ qsort(aio, n, sizeof(*aio), comp_dst); /* reorder the addrinfo chain. */ for (i = 0, aip = &sentinel->ai_next; i < n; i++) { *aip = aio[i].aio_ai; aip = &aio[i].aio_ai->ai_next; } *aip = NULL; /* cleanup and return */ free(aio); free_addrselectpolicy(&policyhead); return(n); } static int get_addrselectpolicy(head) struct policyhead *head; { #ifdef INET6 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; size_t l; char *buf; struct in6_addrpolicy *pol, *ep; if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) return (0); if ((buf = malloc(l)) == NULL) return (0); if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { free(buf); return (0); } ep = (struct in6_addrpolicy *)(buf + l); for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { struct policyqueue *new; if ((new = malloc(sizeof(*new))) == NULL) { free_addrselectpolicy(head); /* make the list empty */ break; } new->pc_policy = *pol; TAILQ_INSERT_TAIL(head, new, pc_entry); } free(buf); return (1); #else return (0); #endif } static void free_addrselectpolicy(head) struct policyhead *head; { struct policyqueue *ent, *nent; for (ent = TAILQ_FIRST(head); ent; ent = nent) { nent = TAILQ_NEXT(ent, pc_entry); TAILQ_REMOVE(head, ent, pc_entry); free(ent); } } static struct policyqueue * match_addrselectpolicy(addr, head) struct sockaddr *addr; struct policyhead *head; { #ifdef INET6 struct policyqueue *ent, *bestent = NULL; struct in6_addrpolicy *pol; int matchlen, bestmatchlen = -1; u_char *mp, *ep, *k, *p, m; struct sockaddr_in6 key; switch(addr->sa_family) { case AF_INET6: key = *(struct sockaddr_in6 *)addr; break; case AF_INET: /* convert the address into IPv4-mapped IPv6 address. */ memset(&key, 0, sizeof(key)); key.sin6_family = AF_INET6; key.sin6_len = sizeof(key); key.sin6_addr.s6_addr[10] = 0xff; key.sin6_addr.s6_addr[11] = 0xff; memcpy(&key.sin6_addr.s6_addr[12], &((struct sockaddr_in *)addr)->sin_addr, 4); break; default: return(NULL); } for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { pol = &ent->pc_policy; matchlen = 0; mp = (u_char *)&pol->addrmask.sin6_addr; ep = mp + 16; /* XXX: scope field? */ k = (u_char *)&key.sin6_addr; p = (u_char *)&pol->addr.sin6_addr; for (; mp < ep && *mp; mp++, k++, p++) { m = *mp; if ((*k & m) != *p) goto next; /* not match */ if (m == 0xff) /* short cut for a typical case */ matchlen += 8; else { while (m >= 0x80) { matchlen++; m <<= 1; } } } /* matched. check if this is better than the current best. */ if (matchlen > bestmatchlen) { bestent = ent; bestmatchlen = matchlen; } next: continue; } return(bestent); #else return(NULL); #endif } static void set_source(aio, ph) struct ai_order *aio; struct policyhead *ph; { struct addrinfo ai = *aio->aio_ai; struct sockaddr_storage ss; int s, srclen; /* set unspec ("no source is available"), just in case */ aio->aio_srcsa.sa_family = AF_UNSPEC; aio->aio_srcscope = -1; switch(ai.ai_family) { case AF_INET: #ifdef INET6 case AF_INET6: #endif break; default: /* ignore unsupported AFs explicitly */ return; } /* XXX: make a dummy addrinfo to call connect() */ ai.ai_socktype = SOCK_DGRAM; ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */ ai.ai_next = NULL; memset(&ss, 0, sizeof(ss)); memcpy(&ss, ai.ai_addr, ai.ai_addrlen); ai.ai_addr = (struct sockaddr *)&ss; get_port(&ai, "1", 0); /* open a socket to get the source address for the given dst */ if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0) return; /* give up */ if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0) goto cleanup; srclen = ai.ai_addrlen; if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { aio->aio_srcsa.sa_family = AF_UNSPEC; goto cleanup; } aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr); #ifdef INET6 if (ai.ai_family == AF_INET6) { struct in6_ifreq ifr6; u_int32_t flags6; /* XXX: interface name should not be hardcoded */ strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name)); memset(&ifr6, 0, sizeof(ifr6)); memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen); if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { flags6 = ifr6.ifr_ifru.ifru_flags6; if ((flags6 & IN6_IFF_DEPRECATED)) aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; } } #endif cleanup: _close(s); return; } static int matchlen(src, dst) struct sockaddr *src, *dst; { int match = 0; u_char *s, *d; u_char *lim, r; int addrlen; switch (src->sa_family) { #ifdef INET6 case AF_INET6: s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; addrlen = sizeof(struct in6_addr); lim = s + addrlen; break; #endif case AF_INET: s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; addrlen = sizeof(struct in_addr); lim = s + addrlen; break; default: return(0); } while (s < lim) if ((r = (*d++ ^ *s++)) != 0) { while (r < addrlen * 8) { match++; r <<= 1; } break; } else match += 8; return(match); } static int comp_dst(arg1, arg2) const void *arg1, *arg2; { const struct ai_order *dst1 = arg1, *dst2 = arg2; /* * Rule 1: Avoid unusable destinations. * XXX: we currently do not consider if an appropriate route exists. */ if (dst1->aio_srcsa.sa_family != AF_UNSPEC && dst2->aio_srcsa.sa_family == AF_UNSPEC) { return(-1); } if (dst1->aio_srcsa.sa_family == AF_UNSPEC && dst2->aio_srcsa.sa_family != AF_UNSPEC) { return(1); } /* Rule 2: Prefer matching scope. */ if (dst1->aio_dstscope == dst1->aio_srcscope && dst2->aio_dstscope != dst2->aio_srcscope) { return(-1); } if (dst1->aio_dstscope != dst1->aio_srcscope && dst2->aio_dstscope == dst2->aio_srcscope) { return(1); } /* Rule 3: Avoid deprecated addresses. */ if (dst1->aio_srcsa.sa_family != AF_UNSPEC && dst2->aio_srcsa.sa_family != AF_UNSPEC) { if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { return(-1); } if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { return(1); } } /* Rule 4: Prefer home addresses. */ /* XXX: not implemented yet */ /* Rule 5: Prefer matching label. */ #ifdef INET6 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && dst1->aio_srcpolicy->pc_policy.label == dst1->aio_dstpolicy->pc_policy.label && (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || dst2->aio_srcpolicy->pc_policy.label != dst2->aio_dstpolicy->pc_policy.label)) { return(-1); } if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && dst2->aio_srcpolicy->pc_policy.label == dst2->aio_dstpolicy->pc_policy.label && (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || dst1->aio_srcpolicy->pc_policy.label != dst1->aio_dstpolicy->pc_policy.label)) { return(1); } #endif /* Rule 6: Prefer higher precedence. */ #ifdef INET6 if (dst1->aio_dstpolicy && (dst2->aio_dstpolicy == NULL || dst1->aio_dstpolicy->pc_policy.preced > dst2->aio_dstpolicy->pc_policy.preced)) { return(-1); } if (dst2->aio_dstpolicy && (dst1->aio_dstpolicy == NULL || dst2->aio_dstpolicy->pc_policy.preced > dst1->aio_dstpolicy->pc_policy.preced)) { return(1); } #endif /* Rule 7: Prefer native transport. */ /* XXX: not implemented yet */ /* Rule 8: Prefer smaller scope. */ if (dst1->aio_dstscope >= 0 && dst1->aio_dstscope < dst2->aio_dstscope) { return(-1); } if (dst2->aio_dstscope >= 0 && dst2->aio_dstscope < dst1->aio_dstscope) { return(1); } /* * Rule 9: Use longest matching prefix. * We compare the match length in a same AF only. */ if (dst1->aio_ai->ai_addr->sa_family == dst2->aio_ai->ai_addr->sa_family) { if (dst1->aio_matchlen > dst2->aio_matchlen) { return(-1); } if (dst1->aio_matchlen < dst2->aio_matchlen) { return(1); } } /* Rule 10: Otherwise, leave the order unchanged. */ return(-1); } /* * Copy from scope.c. * XXX: we should standardize the functions and link them as standard * library. */ static int gai_addr2scopetype(sa) struct sockaddr *sa; { #ifdef INET6 struct sockaddr_in6 *sa6; #endif struct sockaddr_in *sa4; switch(sa->sa_family) { #ifdef INET6 case AF_INET6: sa6 = (struct sockaddr_in6 *)sa; if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { /* just use the scope field of the multicast address */ return(sa6->sin6_addr.s6_addr[2] & 0x0f); } /* * Unicast addresses: map scope type to corresponding scope * value defined for multcast addresses. * XXX: hardcoded scope type values are bad... */ if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) return(1); /* node local scope */ if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) return(2); /* link-local scope */ if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) return(5); /* site-local scope */ return(14); /* global scope */ break; #endif case AF_INET: /* * IPv4 pseudo scoping according to RFC 3484. */ sa4 = (struct sockaddr_in *)sa; /* IPv4 autoconfiguration addresses have link-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 169 && ((u_char *)&sa4->sin_addr)[1] == 254) return(2); /* Private addresses have site-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 10 || (((u_char *)&sa4->sin_addr)[0] == 172 && (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || (((u_char *)&sa4->sin_addr)[0] == 192 && ((u_char *)&sa4->sin_addr)[1] == 168)) return(14); /* XXX: It should be 5 unless NAT */ /* Loopback addresses have link-local scope. */ if (((u_char *)&sa4->sin_addr)[0] == 127) return(2); return(14); break; default: errno = EAFNOSUPPORT; /* is this a good error? */ return(-1); } } /* * hostname == NULL. * passive socket -> anyaddr (0.0.0.0 or ::) * non-passive socket -> localhost (127.0.0.1 or ::1) */ static int explore_null(pai, servname, res) const struct addrinfo *pai; const char *servname; struct addrinfo **res; { int s; const struct afd *afd; struct addrinfo *cur; struct addrinfo sentinel; int error; *res = NULL; sentinel.ai_next = NULL; cur = &sentinel; /* * filter out AFs that are not supported by the kernel * XXX errno? */ s = _socket(pai->ai_family, SOCK_DGRAM, 0); if (s < 0) { if (errno != EMFILE) return 0; } else _close(s); /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) return 0; afd = find_afd(pai->ai_family); if (afd == NULL) return 0; if (pai->ai_flags & AI_PASSIVE) { GET_AI(cur->ai_next, afd, afd->a_addrany); /* xxx meaningless? * GET_CANONNAME(cur->ai_next, "anyaddr"); */ GET_PORT(cur->ai_next, servname); } else { GET_AI(cur->ai_next, afd, afd->a_loopback); /* xxx meaningless? * GET_CANONNAME(cur->ai_next, "localhost"); */ GET_PORT(cur->ai_next, servname); } cur = cur->ai_next; *res = sentinel.ai_next; return 0; free: if (sentinel.ai_next) freeaddrinfo(sentinel.ai_next); return error; } /* * numeric hostname */ static int explore_numeric(pai, hostname, servname, res, canonname) const struct addrinfo *pai; const char *hostname; const char *servname; struct addrinfo **res; const char *canonname; { const struct afd *afd; struct addrinfo *cur; struct addrinfo sentinel; int error; char pton[PTON_MAX]; *res = NULL; sentinel.ai_next = NULL; cur = &sentinel; /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) return 0; afd = find_afd(pai->ai_family); if (afd == NULL) return 0; switch (afd->a_af) { #if 1 /*X/Open spec*/ case AF_INET: if (inet_aton(hostname, (struct in_addr *)pton) == 1) { if (pai->ai_family == afd->a_af || pai->ai_family == PF_UNSPEC /*?*/) { GET_AI(cur->ai_next, afd, pton); GET_PORT(cur->ai_next, servname); if ((pai->ai_flags & AI_CANONNAME)) { /* * Set the numeric address itself as * the canonical name, based on a * clarification in rfc3493. */ GET_CANONNAME(cur->ai_next, canonname); } while (cur && cur->ai_next) cur = cur->ai_next; } else ERR(EAI_FAMILY); /*xxx*/ } break; #endif default: if (inet_pton(afd->a_af, hostname, pton) == 1) { if (pai->ai_family == afd->a_af || pai->ai_family == PF_UNSPEC /*?*/) { GET_AI(cur->ai_next, afd, pton); GET_PORT(cur->ai_next, servname); if ((pai->ai_flags & AI_CANONNAME)) { /* * Set the numeric address itself as * the canonical name, based on a * clarification in rfc3493. */ GET_CANONNAME(cur->ai_next, canonname); } while (cur && cur->ai_next) cur = cur->ai_next; } else ERR(EAI_FAMILY); /* XXX */ } break; } *res = sentinel.ai_next; return 0; free: bad: if (sentinel.ai_next) freeaddrinfo(sentinel.ai_next); return error; } /* * numeric hostname with scope */ static int explore_numeric_scope(pai, hostname, servname, res) const struct addrinfo *pai; const char *hostname; const char *servname; struct addrinfo **res; { #if !defined(SCOPE_DELIMITER) || !defined(INET6) return explore_numeric(pai, hostname, servname, res, hostname); #else const struct afd *afd; struct addrinfo *cur; int error; char *cp, *hostname2 = NULL, *scope, *addr; struct sockaddr_in6 *sin6; /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) return 0; afd = find_afd(pai->ai_family); if (afd == NULL) return 0; if (!afd->a_scoped) return explore_numeric(pai, hostname, servname, res, hostname); cp = strchr(hostname, SCOPE_DELIMITER); if (cp == NULL) return explore_numeric(pai, hostname, servname, res, hostname); /* * Handle special case of */ hostname2 = strdup(hostname); if (hostname2 == NULL) return EAI_MEMORY; /* terminate at the delimiter */ hostname2[cp - hostname] = '\0'; addr = hostname2; scope = cp + 1; error = explore_numeric(pai, addr, servname, res, hostname); if (error == 0) { u_int32_t scopeid; for (cur = *res; cur; cur = cur->ai_next) { if (cur->ai_family != AF_INET6) continue; sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr; if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) { free(hostname2); return(EAI_NONAME); /* XXX: is return OK? */ } sin6->sin6_scope_id = scopeid; } } free(hostname2); return error; #endif } static int get_canonname(pai, ai, str) const struct addrinfo *pai; struct addrinfo *ai; const char *str; { if ((pai->ai_flags & AI_CANONNAME) != 0) { ai->ai_canonname = strdup(str); if (ai->ai_canonname == NULL) return EAI_MEMORY; } return 0; } static struct addrinfo * get_ai(pai, afd, addr) const struct addrinfo *pai; const struct afd *afd; const char *addr; { char *p; struct addrinfo *ai; #ifdef FAITH struct in6_addr faith_prefix; char *fp_str; int translate = 0; #endif #ifdef FAITH /* * Transfrom an IPv4 addr into a special IPv6 addr format for * IPv6->IPv4 translation gateway. (only TCP is supported now) * * +-----------------------------------+------------+ * | faith prefix part (12 bytes) | embedded | * | | IPv4 addr part (4 bytes) * +-----------------------------------+------------+ * * faith prefix part is specified as ascii IPv6 addr format * in environmental variable GAI. * For FAITH to work correctly, routing to faith prefix must be * setup toward a machine where a FAITH daemon operates. * Also, the machine must enable some mechanizm * (e.g. faith interface hack) to divert those packet with * faith prefixed destination addr to user-land FAITH daemon. */ fp_str = getenv("GAI"); if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 && afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) { u_int32_t v4a; u_int8_t v4a_top; memcpy(&v4a, addr, sizeof v4a); v4a_top = v4a >> IN_CLASSA_NSHIFT; if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) && v4a_top != 0 && v4a != IN_LOOPBACKNET) { afd = &afdl[N_INET6]; memcpy(&faith_prefix.s6_addr[12], addr, sizeof(struct in_addr)); translate = 1; } } #endif ai = (struct addrinfo *)malloc(sizeof(struct addrinfo) + (afd->a_socklen)); if (ai == NULL) return NULL; memcpy(ai, pai, sizeof(struct addrinfo)); ai->ai_addr = (struct sockaddr *)(void *)(ai + 1); memset(ai->ai_addr, 0, (size_t)afd->a_socklen); ai->ai_addr->sa_len = afd->a_socklen; ai->ai_addrlen = afd->a_socklen; ai->ai_addr->sa_family = ai->ai_family = afd->a_af; p = (char *)(void *)(ai->ai_addr); #ifdef FAITH if (translate == 1) memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen); else #endif memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen); return ai; } static int get_portmatch(ai, servname) const struct addrinfo *ai; const char *servname; { /* get_port does not touch first argument when matchonly == 1. */ /* LINTED const cast */ return get_port((struct addrinfo *)ai, servname, 1); } static int get_port(ai, servname, matchonly) struct addrinfo *ai; const char *servname; int matchonly; { const char *proto; struct servent *sp; int port; int allownumeric; if (servname == NULL) return 0; switch (ai->ai_family) { case AF_INET: #ifdef AF_INET6 case AF_INET6: #endif break; default: return 0; } switch (ai->ai_socktype) { case SOCK_RAW: return EAI_SERVICE; case SOCK_DGRAM: case SOCK_STREAM: allownumeric = 1; break; case ANY: allownumeric = 0; break; default: return EAI_SOCKTYPE; } port = str2number(servname); if (port >= 0) { if (!allownumeric) return EAI_SERVICE; if (port < 0 || port > 65535) return EAI_SERVICE; port = htons(port); } else { if (ai->ai_flags & AI_NUMERICSERV) return EAI_NONAME; switch (ai->ai_socktype) { case SOCK_DGRAM: proto = "udp"; break; case SOCK_STREAM: proto = "tcp"; break; default: proto = NULL; break; } THREAD_LOCK(); if ((sp = getservbyname(servname, proto)) == NULL) { THREAD_UNLOCK(); return EAI_SERVICE; } port = sp->s_port; THREAD_UNLOCK(); } if (!matchonly) { switch (ai->ai_family) { case AF_INET: ((struct sockaddr_in *)(void *) ai->ai_addr)->sin_port = port; break; #ifdef INET6 case AF_INET6: ((struct sockaddr_in6 *)(void *) ai->ai_addr)->sin6_port = port; break; #endif } } return 0; } static const struct afd * find_afd(af) int af; { const struct afd *afd; if (af == PF_UNSPEC) return NULL; for (afd = afdl; afd->a_af; afd++) { if (afd->a_af == af) return afd; } return NULL; } /* * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend * will take care of it. * the semantics of AI_ADDRCONFIG is not defined well. we are not sure * if the code is right or not. * * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with * _dns_getaddrinfo. */ static int addrconfig(pai) struct addrinfo *pai; { int s, af; /* * TODO: * Note that implementation dependent test for address * configuration should be done everytime called * (or apropriate interval), * because addresses will be dynamically assigned or deleted. */ af = pai->ai_family; if (af == AF_UNSPEC) { if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0) af = AF_INET; else { _close(s); if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0) af = AF_INET6; else _close(s); } } if (af != AF_UNSPEC) { if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) return 0; _close(s); } pai->ai_family = af; return 1; } #ifdef INET6 /* convert a string to a scope identifier. XXX: IPv6 specific */ static int ip6_str2scopeid(scope, sin6, scopeid) char *scope; struct sockaddr_in6 *sin6; u_int32_t *scopeid; { u_long lscopeid; struct in6_addr *a6; char *ep; a6 = &sin6->sin6_addr; /* empty scopeid portion is invalid */ if (*scope == '\0') return -1; if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) { /* * We currently assume a one-to-one mapping between links * and interfaces, so we simply use interface indices for * like-local scopes. */ *scopeid = if_nametoindex(scope); if (*scopeid == 0) goto trynumeric; return 0; } /* still unclear about literal, allow numeric only - placeholder */ if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6)) goto trynumeric; if (IN6_IS_ADDR_MC_ORGLOCAL(a6)) goto trynumeric; else goto trynumeric; /* global */ /* try to convert to a numeric id as a last resort */ trynumeric: errno = 0; lscopeid = strtoul(scope, &ep, 10); *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL); if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid) return 0; else return -1; } #endif /* * FQDN hostname, DNS lookup */ static int explore_fqdn(pai, hostname, servname, res) const struct addrinfo *pai; const char *hostname; const char *servname; struct addrinfo **res; { struct addrinfo *result; struct addrinfo *cur; int error = 0; static const ns_dtab dtab[] = { NS_FILES_CB(_files_getaddrinfo, NULL) { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */ NS_NIS_CB(_yp_getaddrinfo, NULL) { 0 } }; result = NULL; /* * if the servname does not match socktype/protocol, ignore it. */ if (get_portmatch(pai, servname) != 0) return 0; switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo", default_dns_files, hostname, pai)) { case NS_TRYAGAIN: error = EAI_AGAIN; goto free; case NS_UNAVAIL: error = EAI_FAIL; goto free; case NS_NOTFOUND: error = EAI_NONAME; goto free; case NS_SUCCESS: error = 0; for (cur = result; cur; cur = cur->ai_next) { GET_PORT(cur, servname); /* canonname should be filled already */ } break; } *res = result; return 0; free: if (result) freeaddrinfo(result); return error; } #ifdef DEBUG static const char AskedForGot[] = "gethostby*.getanswer: asked for \"%s\", got \"%s\""; #endif static struct addrinfo * getanswer(answer, anslen, qname, qtype, pai) const querybuf *answer; int anslen; const char *qname; int qtype; const struct addrinfo *pai; { struct addrinfo sentinel, *cur; struct addrinfo ai; const struct afd *afd; char *canonname; const HEADER *hp; const u_char *cp; int n; const u_char *eom; char *bp, *ep; int type, class, ancount, qdcount; int haveanswer, had_error; char tbuf[MAXDNAME]; int (*name_ok)(const char *); char hostbuf[8*1024]; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; canonname = NULL; eom = answer->buf + anslen; switch (qtype) { case T_A: case T_AAAA: case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/ name_ok = res_hnok; break; default: return (NULL); /* XXX should be abort(); */ } /* * find first satisfactory answer */ hp = &answer->hdr; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); bp = hostbuf; ep = hostbuf + sizeof hostbuf; cp = answer->buf + HFIXEDSZ; if (qdcount != 1) { h_errno = NO_RECOVERY; return (NULL); } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { h_errno = NO_RECOVERY; return (NULL); } cp += n + QFIXEDSZ; if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) { /* res_send() has already verified that the query name is the * same as the one we sent; this just gets the expanded name * (i.e., with the succeeding search-domain tacked on). */ n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { h_errno = NO_RECOVERY; return (NULL); } canonname = bp; bp += n; /* The qname can be abbreviated, but h_name is now absolute. */ qname = canonname; } haveanswer = 0; had_error = 0; while (ancount-- > 0 && cp < eom && !had_error) { n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { had_error++; continue; } cp += n; /* name */ type = _getshort(cp); cp += INT16SZ; /* type */ class = _getshort(cp); cp += INT16SZ + INT32SZ; /* class, TTL */ n = _getshort(cp); cp += INT16SZ; /* len */ if (class != C_IN) { /* XXX - debug? syslog? */ cp += n; continue; /* XXX - had_error++ ? */ } if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) && type == T_CNAME) { n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if ((n < 0) || !(*name_ok)(tbuf)) { had_error++; continue; } cp += n; /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strlcpy(bp, tbuf, ep - bp); canonname = bp; bp += n; continue; } if (qtype == T_ANY) { if (!(type == T_A || type == T_AAAA)) { cp += n; continue; } } else if (type != qtype) { #ifdef DEBUG if (type != T_KEY && type != T_SIG) syslog(LOG_NOTICE|LOG_AUTH, "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"", qname, p_class(C_IN), p_type(qtype), p_type(type)); #endif cp += n; continue; /* XXX - had_error++ ? */ } switch (type) { case T_A: case T_AAAA: if (strcasecmp(canonname, bp) != 0) { #ifdef DEBUG syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, canonname, bp); #endif cp += n; continue; /* XXX - had_error++ ? */ } if (type == T_A && n != INADDRSZ) { cp += n; continue; } if (type == T_AAAA && n != IN6ADDRSZ) { cp += n; continue; } #ifdef FILTER_V4MAPPED if (type == T_AAAA) { struct in6_addr in6; memcpy(&in6, cp, sizeof(in6)); if (IN6_IS_ADDR_V4MAPPED(&in6)) { cp += n; continue; } } #endif if (!haveanswer) { int nn; canonname = bp; nn = strlen(bp) + 1; /* for the \0 */ bp += nn; } /* don't overwrite pai */ ai = *pai; ai.ai_family = (type == T_A) ? AF_INET : AF_INET6; afd = find_afd(ai.ai_family); if (afd == NULL) { cp += n; continue; } cur->ai_next = get_ai(&ai, afd, (const char *)cp); if (cur->ai_next == NULL) had_error++; while (cur && cur->ai_next) cur = cur->ai_next; cp += n; break; default: abort(); } if (!had_error) haveanswer++; } if (haveanswer) { #if defined(RESOLVSORT) /* * We support only IPv4 address for backward * compatibility against gethostbyname(3). */ if (_res.nsort && qtype == T_A) { if (addr4sort(&sentinel) < 0) { freeaddrinfo(sentinel.ai_next); h_errno = NO_RECOVERY; return NULL; } } #endif /*RESOLVSORT*/ if (!canonname) (void)get_canonname(pai, sentinel.ai_next, qname); else (void)get_canonname(pai, sentinel.ai_next, canonname); h_errno = NETDB_SUCCESS; return sentinel.ai_next; } h_errno = NO_RECOVERY; return NULL; } #ifdef RESOLVSORT struct addr_ptr { struct addrinfo *ai; int aval; }; static int addr4sort(struct addrinfo *sentinel) { struct addrinfo *ai; struct addr_ptr *addrs, addr; struct sockaddr_in *sin; int naddrs, i, j; int needsort = 0; if (!sentinel) return -1; naddrs = 0; for (ai = sentinel->ai_next; ai; ai = ai->ai_next) naddrs++; if (naddrs < 2) return 0; /* We don't need sorting. */ if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL) return -1; i = 0; for (ai = sentinel->ai_next; ai; ai = ai->ai_next) { sin = (struct sockaddr_in *)ai->ai_addr; for (j = 0; (unsigned)j < _res.nsort; j++) { if (_res.sort_list[j].addr.s_addr == (sin->sin_addr.s_addr & _res.sort_list[j].mask)) break; } addrs[i].ai = ai; addrs[i].aval = j; if (needsort == 0 && i > 0 && j < addrs[i - 1].aval) needsort = i; i++; } if (!needsort) { free(addrs); return 0; } while (needsort < naddrs) { for (j = needsort - 1; j >= 0; j--) { if (addrs[j].aval > addrs[j+1].aval) { addr = addrs[j]; addrs[j] = addrs[j + 1]; addrs[j + 1] = addr; } else break; } needsort++; } ai = sentinel; for (i = 0; i < naddrs; ++i) { ai->ai_next = addrs[i].ai; ai = ai->ai_next; } ai->ai_next = NULL; free(addrs); return 0; } #endif /*RESOLVSORT*/ /*ARGSUSED*/ static int _dns_getaddrinfo(rv, cb_data, ap) void *rv; void *cb_data; va_list ap; { struct addrinfo *ai; querybuf *buf, *buf2; const char *hostname; const struct addrinfo *pai; struct addrinfo sentinel, *cur; struct res_target q, q2; hostname = va_arg(ap, char *); pai = va_arg(ap, const struct addrinfo *); memset(&q, 0, sizeof(q2)); memset(&q2, 0, sizeof(q2)); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; buf = malloc(sizeof(*buf)); if (!buf) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } buf2 = malloc(sizeof(*buf2)); if (!buf2) { free(buf); h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } switch (pai->ai_family) { case AF_UNSPEC: q.name = hostname; q.qclass = C_IN; q.qtype = T_A; q.answer = buf->buf; q.anslen = sizeof(buf->buf); q.next = &q2; q2.name = hostname; q2.qclass = C_IN; q2.qtype = T_AAAA; q2.answer = buf2->buf; q2.anslen = sizeof(buf2->buf); break; case AF_INET: q.name = hostname; q.qclass = C_IN; q.qtype = T_A; q.answer = buf->buf; q.anslen = sizeof(buf->buf); break; case AF_INET6: q.name = hostname; q.qclass = C_IN; q.qtype = T_AAAA; q.answer = buf->buf; q.anslen = sizeof(buf->buf); break; default: free(buf); free(buf2); return NS_UNAVAIL; } if (res_searchN(hostname, &q) < 0) { free(buf); free(buf2); return NS_NOTFOUND; } /* prefer IPv6 */ if (q.next) { ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai); if (ai) { cur->ai_next = ai; while (cur && cur->ai_next) cur = cur->ai_next; } } ai = getanswer(buf, q.n, q.name, q.qtype, pai); if (ai) cur->ai_next = ai; free(buf); free(buf2); if (sentinel.ai_next == NULL) switch (h_errno) { case HOST_NOT_FOUND: return NS_NOTFOUND; case TRY_AGAIN: return NS_TRYAGAIN; default: return NS_UNAVAIL; } *((struct addrinfo **)rv) = sentinel.ai_next; return NS_SUCCESS; } static void _sethtent(FILE **hostf) { if (!*hostf) *hostf = fopen(_PATH_HOSTS, "r"); else rewind(*hostf); } static void _endhtent(FILE **hostf) { if (*hostf) { (void) fclose(*hostf); *hostf = NULL; } } static struct addrinfo * _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai) { char *p; char *cp, *tname, *cname; struct addrinfo hints, *res0, *res; int error; const char *addr; char hostbuf[8*1024]; if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r"))) return (NULL); again: if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf))) return (NULL); if (*p == '#') goto again; cp = strpbrk(p, "#\n"); if (cp != NULL) *cp = '\0'; if (!(cp = strpbrk(p, " \t"))) goto again; *cp++ = '\0'; addr = p; cname = NULL; /* if this is not something we're looking for, skip it. */ while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } tname = cp; if (cname == NULL) cname = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; if (strcasecmp(name, tname) == 0) goto found; } goto again; found: /* we should not glob socktype/protocol here */ memset(&hints, 0, sizeof(hints)); hints.ai_family = pai->ai_family; hints.ai_socktype = SOCK_DGRAM; hints.ai_protocol = 0; hints.ai_flags = AI_NUMERICHOST; error = getaddrinfo(addr, "0", &hints, &res0); if (error) goto again; #ifdef FILTER_V4MAPPED /* XXX should check all items in the chain */ if (res0->ai_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) { freeaddrinfo(res0); goto again; } #endif for (res = res0; res; res = res->ai_next) { /* cover it up */ res->ai_flags = pai->ai_flags; res->ai_socktype = pai->ai_socktype; res->ai_protocol = pai->ai_protocol; if (pai->ai_flags & AI_CANONNAME) { if (get_canonname(pai, res, cname) != 0) { freeaddrinfo(res0); goto again; } } } return res0; } /*ARGSUSED*/ static int _files_getaddrinfo(rv, cb_data, ap) void *rv; void *cb_data; va_list ap; { const char *name; const struct addrinfo *pai; struct addrinfo sentinel, *cur; struct addrinfo *p; FILE *hostf = NULL; name = va_arg(ap, char *); pai = va_arg(ap, struct addrinfo *); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; _sethtent(&hostf); while ((p = _gethtent(&hostf, name, pai)) != NULL) { cur->ai_next = p; while (cur && cur->ai_next) cur = cur->ai_next; } _endhtent(&hostf); *((struct addrinfo **)rv) = sentinel.ai_next; if (sentinel.ai_next == NULL) return NS_NOTFOUND; return NS_SUCCESS; } #ifdef YP /*ARGSUSED*/ static struct addrinfo * _yphostent(line, pai) char *line; const struct addrinfo *pai; { struct addrinfo sentinel, *cur; struct addrinfo hints, *res, *res0; int error; char *p = line; const char *addr, *canonname; char *nextline; char *cp; addr = canonname = NULL; memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; nextline: /* terminate line */ cp = strchr(p, '\n'); if (cp) { *cp++ = '\0'; nextline = cp; } else nextline = NULL; cp = strpbrk(p, " \t"); if (cp == NULL) { if (canonname == NULL) return (NULL); else goto done; } *cp++ = '\0'; addr = p; while (cp && *cp) { if (*cp == ' ' || *cp == '\t') { cp++; continue; } if (!canonname) canonname = cp; if ((cp = strpbrk(cp, " \t")) != NULL) *cp++ = '\0'; } hints = *pai; hints.ai_flags = AI_NUMERICHOST; error = getaddrinfo(addr, NULL, &hints, &res0); if (error == 0) { for (res = res0; res; res = res->ai_next) { /* cover it up */ res->ai_flags = pai->ai_flags; if (pai->ai_flags & AI_CANONNAME) (void)get_canonname(pai, res, canonname); } } else res0 = NULL; if (res0) { cur->ai_next = res0; while (cur && cur->ai_next) cur = cur->ai_next; } if (nextline) { p = nextline; goto nextline; } done: return sentinel.ai_next; } /*ARGSUSED*/ static int _yp_getaddrinfo(rv, cb_data, ap) void *rv; void *cb_data; va_list ap; { struct addrinfo sentinel, *cur; struct addrinfo *ai = NULL; char *ypbuf; int ypbuflen, r; const char *name; const struct addrinfo *pai; char *ypdomain; if (_yp_check(&ypdomain) == 0) return NS_UNAVAIL; name = va_arg(ap, char *); pai = va_arg(ap, const struct addrinfo *); memset(&sentinel, 0, sizeof(sentinel)); cur = &sentinel; /* hosts.byname is only for IPv4 (Solaris8) */ if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) { r = yp_match(ypdomain, "hosts.byname", name, (int)strlen(name), &ypbuf, &ypbuflen); if (r == 0) { struct addrinfo ai4; ai4 = *pai; ai4.ai_family = AF_INET; ai = _yphostent(ypbuf, &ai4); if (ai) { cur->ai_next = ai; while (cur && cur->ai_next) cur = cur->ai_next; } } free(ypbuf); } /* ipnodes.byname can hold both IPv4/v6 */ r = yp_match(ypdomain, "ipnodes.byname", name, (int)strlen(name), &ypbuf, &ypbuflen); if (r == 0) { ai = _yphostent(ypbuf, pai); if (ai) cur->ai_next = ai; free(ypbuf); } if (sentinel.ai_next == NULL) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } *((struct addrinfo **)rv) = sentinel.ai_next; return NS_SUCCESS; } #endif /* resolver logic */ -extern const char *__hostalias(const char *); +extern const char *_res_hostalias(const char *, char *, size_t); /* * Formulate a normal query, send, and await answer. * Returned answer is placed in supplied buffer "answer". * Perform preliminary check of answer, returning success only * if no error is indicated and the answer count is nonzero. * Return the size of the response on success, -1 on error. * Error number is left in h_errno. * * Caller must parse answer and determine whether it answers the question. */ static int res_queryN(name, target) const char *name; /* domain name */ struct res_target *target; { u_char *buf; HEADER *hp; int n; struct res_target *t; int rcode; int ancount; rcode = NOERROR; ancount = 0; buf = malloc(MAXPACKET); if (!buf) { h_errno = NETDB_INTERNAL; return -1; } for (t = target; t; t = t->next) { int class, type; u_char *answer; int anslen; hp = (HEADER *)(void *)t->answer; hp->rcode = NOERROR; /* default */ /* make it easier... */ class = t->qclass; type = t->qtype; answer = t->answer; anslen = t->anslen; #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query(%s, %d, %d)\n", name, class, type); #endif n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, buf, MAXPACKET); if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) n = res_opt(n, buf, MAXPACKET, anslen); if (n <= 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query: mkquery failed\n"); #endif free(buf); h_errno = NO_RECOVERY; return (n); } n = res_send(buf, n, answer, anslen); #if 0 if (n < 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query: send error\n"); #endif free(buf); h_errno = TRY_AGAIN; return (n); } #endif if (n < 0 || n > anslen) hp->rcode = FORMERR; /* XXX not very informative */ if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { rcode = hp->rcode; /* record most recent error */ #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; rcode = %u, ancount=%u\n", hp->rcode, ntohs(hp->ancount)); #endif continue; } ancount += ntohs(hp->ancount); t->n = n; } free(buf); if (ancount == 0) { switch (rcode) { case NXDOMAIN: h_errno = HOST_NOT_FOUND; break; case SERVFAIL: h_errno = TRY_AGAIN; break; case NOERROR: h_errno = NO_DATA; break; case FORMERR: case NOTIMP: case REFUSED: default: h_errno = NO_RECOVERY; break; } return (-1); } return (ancount); } /* * Formulate a normal query, send, and retrieve answer in supplied buffer. * Return the size of the response on success, -1 on error. * If enabled, implement search rules until answer or unrecoverable failure * is detected. Error code, if any, is left in h_errno. */ static int res_searchN(name, target) const char *name; /* domain name */ struct res_target *target; { const char *cp, * const *domain; HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/ u_int dots; int trailing_dot, ret, saved_herrno; int got_nodata = 0, got_servfail = 0, tried_as_is = 0; + char abuf[MAXDNAME]; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (-1); } errno = 0; h_errno = HOST_NOT_FOUND; /* default, if we never query */ dots = 0; for (cp = name; *cp; cp++) dots += (*cp == '.'); trailing_dot = 0; if (cp > name && *--cp == '.') trailing_dot++; /* * if there aren't any dots, it could be a user-level alias */ - if (!dots && (cp = __hostalias(name)) != NULL) + if (!dots && (cp = _res_hostalias(name, abuf, sizeof(abuf))) != NULL) return (res_queryN(cp, target)); /* * If there are dots in the name already, let's just give it a try * 'as is'. The threshold can be set with the "ndots" option. */ saved_herrno = -1; if (dots >= _res.ndots) { ret = res_querydomainN(name, NULL, target); if (ret > 0) return (ret); saved_herrno = h_errno; tried_as_is++; } /* * We do at least one level of search if * - there is no dot and RES_DEFNAME is set, or * - there is at least one dot, there is no trailing dot, * and RES_DNSRCH is set. */ if ((!dots && (_res.options & RES_DEFNAMES)) || (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { int done = 0; for (domain = (const char * const *)_res.dnsrch; *domain && !done; domain++) { ret = res_querydomainN(name, *domain, target); if (ret > 0) return (ret); /* * If no server present, give up. * If name isn't found in this domain, * keep trying higher domains in the search list * (if that's enabled). * On a NO_DATA error, keep trying, otherwise * a wildcard entry of another type could keep us * from finding this entry higher in the domain. * If we get some other error (negative answer or * server failure), then stop searching up, * but try the input name below in case it's * fully-qualified. */ if (errno == ECONNREFUSED) { h_errno = TRY_AGAIN; return (-1); } switch (h_errno) { case NO_DATA: got_nodata++; /* FALLTHROUGH */ case HOST_NOT_FOUND: /* keep trying */ break; case TRY_AGAIN: if (hp->rcode == SERVFAIL) { /* try next search element, if any */ got_servfail++; break; } /* FALLTHROUGH */ default: /* anything else implies that we're done */ done++; } /* * if we got here for some reason other than DNSRCH, * we only wanted one iteration of the loop, so stop. */ if (!(_res.options & RES_DNSRCH)) done++; } } /* * if we have not already tried the name "as is", do that now. * note that we do this regardless of how many dots were in the * name or whether it ends with a dot. */ if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { ret = res_querydomainN(name, NULL, target); if (ret > 0) return (ret); } /* * if we got here, we didn't satisfy the search. * if we did an initial full query, return that query's h_errno * (note that we wouldn't be here if that query had succeeded). * else if we ever got a nodata, send that back as the reason. * else send back meaningless h_errno, that being the one from * the last DNSRCH we did. */ if (saved_herrno != -1) h_errno = saved_herrno; else if (got_nodata) h_errno = NO_DATA; else if (got_servfail) h_errno = TRY_AGAIN; return (-1); } /* * Perform a call on res_query on the concatenation of name and domain, * removing a trailing dot from name if domain is NULL. */ static int res_querydomainN(name, domain, target) const char *name, *domain; struct res_target *target; { char nbuf[MAXDNAME]; const char *longname = nbuf; size_t n, d; #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_querydomain(%s, %s)\n", name, domain?domain:""); #endif if (domain == NULL) { /* * Check for trailing '.'; * copy without '.' if present. */ n = strlen(name); if (n >= MAXDNAME) { h_errno = NO_RECOVERY; return (-1); } if (n > 0 && name[--n] == '.') { strncpy(nbuf, name, n); nbuf[n] = '\0'; } else longname = name; } else { n = strlen(name); d = strlen(domain); if (n + d + 1 >= MAXDNAME) { h_errno = NO_RECOVERY; return (-1); } snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain); } return (res_queryN(longname, target)); } Index: head/lib/libc/net/gethostbydns.c =================================================================== --- head/lib/libc/net/gethostbydns.c (revision 145112) +++ head/lib/libc/net/gethostbydns.c (revision 145113) @@ -1,807 +1,811 @@ /* * ++Copyright++ 1985, 1988, 1993 * - * Copyright (c) 1985, 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * Portions Copyright (c) 1993 by Digital Equipment Corporation. * * 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, and that * the name of Digital Equipment Corporation not be used in advertising or * publicity pertaining to distribution of the document or software without * specific, written prior permission. * * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT * CORPORATION 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. * - * --Copyright-- */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93"; static char fromrcsid[] = "From: Id: gethnamaddr.c,v 8.23 1998/04/07 04:59:46 vixie Exp $"; #endif /* LIBC_SCCS and not lint */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "res_config.h" #define SPRINTF(x) ((size_t)sprintf x) #define MAXALIASES 35 #define MAXADDRS 35 static const char AskedForGot[] = "gethostby*.gethostanswer: asked for \"%s\", got \"%s\""; static char *h_addr_ptrs[MAXADDRS + 1]; static struct hostent host; static char *host_aliases[MAXALIASES]; static char hostbuf[8*1024]; static u_char host_addr[16]; /* IPv4 or IPv6 */ +extern const char *_res_hostalias(const char *, char *, size_t); + #ifdef RESOLVSORT static void addrsort(char **, int); #endif #ifdef DEBUG static void dprintf(char *, int) __printflike(1, 0); #endif #define MAXPACKET (64*1024) typedef union { HEADER hdr; u_char buf[MAXPACKET]; } querybuf; typedef union { int32_t al; char ac; } align; int _dns_ttl_; #ifdef DEBUG static void dprintf(msg, num) char *msg; int num; { if (_res.options & RES_DEBUG) { int save = errno; printf(msg, num); errno = save; } } #else # define dprintf(msg, num) /*nada*/ #endif #define BOUNDED_INCR(x) \ do { \ cp += x; \ if (cp > eom) { \ h_errno = NO_RECOVERY; \ return (NULL); \ } \ } while (0) #define BOUNDS_CHECK(ptr, count) \ do { \ if ((ptr) + (count) > eom) { \ h_errno = NO_RECOVERY; \ return (NULL); \ } \ } while (0) static struct hostent * gethostanswer(answer, anslen, qname, qtype) const querybuf *answer; int anslen; const char *qname; int qtype; { const HEADER *hp; const u_char *cp; int n; const u_char *eom, *erdata; char *bp, *ep, **ap, **hap; int type, class, ancount, qdcount; int haveanswer, had_error; int toobig = 0; char tbuf[MAXDNAME]; const char *tname; int (*name_ok)(const char *); tname = qname; host.h_name = NULL; eom = answer->buf + anslen; switch (qtype) { case T_A: case T_AAAA: name_ok = res_hnok; break; case T_PTR: name_ok = res_dnok; break; default: h_errno = NO_RECOVERY; return (NULL); /* XXX should be abort(); */ } /* * find first satisfactory answer */ hp = &answer->hdr; ancount = ntohs(hp->ancount); qdcount = ntohs(hp->qdcount); bp = hostbuf; ep = hostbuf + sizeof hostbuf; cp = answer->buf; BOUNDED_INCR(HFIXEDSZ); if (qdcount != 1) { h_errno = NO_RECOVERY; return (NULL); } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { h_errno = NO_RECOVERY; return (NULL); } BOUNDED_INCR(n + QFIXEDSZ); if (qtype == T_A || qtype == T_AAAA) { /* res_send() has already verified that the query name is the * same as the one we sent; this just gets the expanded name * (i.e., with the succeeding search-domain tacked on). */ n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { h_errno = NO_RECOVERY; return (NULL); } host.h_name = bp; bp += n; /* The qname can be abbreviated, but h_name is now absolute. */ qname = host.h_name; } ap = host_aliases; *ap = NULL; host.h_aliases = host_aliases; hap = h_addr_ptrs; *hap = NULL; host.h_addr_list = h_addr_ptrs; haveanswer = 0; had_error = 0; _dns_ttl_ = -1; while (ancount-- > 0 && cp < eom && !had_error) { n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !(*name_ok)(bp)) { had_error++; continue; } cp += n; /* name */ BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); type = _getshort(cp); cp += INT16SZ; /* type */ class = _getshort(cp); cp += INT16SZ; /* class */ if (qtype == T_A && type == T_A) _dns_ttl_ = _getlong(cp); cp += INT32SZ; /* TTL */ n = _getshort(cp); cp += INT16SZ; /* len */ BOUNDS_CHECK(cp, n); erdata = cp + n; if (class != C_IN) { /* XXX - debug? syslog? */ cp += n; continue; /* XXX - had_error++ ? */ } if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { if (ap >= &host_aliases[MAXALIASES-1]) continue; n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if ((n < 0) || !(*name_ok)(tbuf)) { had_error++; continue; } cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return (NULL); } /* Store alias. */ *ap++ = bp; n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; continue; } bp += n; /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strcpy(bp, tbuf); host.h_name = bp; bp += n; continue; } if (qtype == T_PTR && type == T_CNAME) { n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); if (n < 0 || !res_dnok(tbuf)) { had_error++; continue; } cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return (NULL); } /* Get canonical name. */ n = strlen(tbuf) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) { had_error++; continue; } strcpy(bp, tbuf); tname = bp; bp += n; continue; } if (type != qtype) { if (type != T_SIG) syslog(LOG_NOTICE|LOG_AUTH, "gethostby*.gethostanswer: asked for \"%s %s %s\", got type \"%s\"", qname, p_class(C_IN), p_type(qtype), p_type(type)); cp += n; continue; /* XXX - had_error++ ? */ } switch (type) { case T_PTR: if (strcasecmp(tname, bp) != 0) { syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, qname, bp); cp += n; continue; /* XXX - had_error++ ? */ } n = dn_expand(answer->buf, eom, cp, bp, ep - bp); if ((n < 0) || !res_hnok(bp)) { had_error++; break; } #if MULTI_PTRS_ARE_ALIASES cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return (NULL); } if (!haveanswer) host.h_name = bp; else if (ap < &host_aliases[MAXALIASES-1]) *ap++ = bp; else n = -1; if (n != -1) { n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; break; } bp += n; } break; #else host.h_name = bp; if (_res.options & RES_USE_INET6) { n = strlen(bp) + 1; /* for the \0 */ if (n >= MAXHOSTNAMELEN) { had_error++; break; } bp += n; _map_v4v6_hostent(&host, &bp, &ep); } h_errno = NETDB_SUCCESS; return (&host); #endif case T_A: case T_AAAA: if (strcasecmp(host.h_name, bp) != 0) { syslog(LOG_NOTICE|LOG_AUTH, AskedForGot, host.h_name, bp); cp += n; continue; /* XXX - had_error++ ? */ } if (n != host.h_length) { cp += n; continue; } if (!haveanswer) { int nn; host.h_name = bp; nn = strlen(bp) + 1; /* for the \0 */ bp += nn; } bp += sizeof(align) - ((u_long)bp % sizeof(align)); if (bp + n >= ep) { dprintf("size (%d) too big\n", n); had_error++; continue; } if (hap >= &h_addr_ptrs[MAXADDRS-1]) { if (!toobig++) dprintf("Too many addresses (%d)\n", MAXADDRS); cp += n; continue; } bcopy(cp, *hap++ = bp, n); bp += n; cp += n; if (cp != erdata) { h_errno = NO_RECOVERY; return (NULL); } break; default: dprintf("Impossible condition (type=%d)\n", type); h_errno = NO_RECOVERY; return (NULL); /* BIND has abort() here, too risky on bad data */ } if (!had_error) haveanswer++; } if (haveanswer) { *ap = NULL; *hap = NULL; # if defined(RESOLVSORT) /* * Note: we sort even if host can take only one address * in its return structures - should give it the "best" * address in that case, not some random one */ if (_res.nsort && haveanswer > 1 && qtype == T_A) addrsort(h_addr_ptrs, haveanswer); # endif /*RESOLVSORT*/ if (!host.h_name) { n = strlen(qname) + 1; /* for the \0 */ if (n > ep - bp || n >= MAXHOSTNAMELEN) goto no_recovery; strcpy(bp, qname); host.h_name = bp; bp += n; } if (_res.options & RES_USE_INET6) _map_v4v6_hostent(&host, &bp, &ep); h_errno = NETDB_SUCCESS; return (&host); } no_recovery: h_errno = NO_RECOVERY; return (NULL); } struct hostent * __dns_getanswer(answer, anslen, qname, qtype) const char *answer; int anslen; const char *qname; int qtype; { switch(qtype) { case T_AAAA: host.h_addrtype = AF_INET6; host.h_length = IN6ADDRSZ; break; case T_A: default: host.h_addrtype = AF_INET; host.h_length = INADDRSZ; break; } return(gethostanswer((const querybuf *)answer, anslen, qname, qtype)); } int _dns_gethostbyname(void *rval, void *cb_data, va_list ap) { const char *name; int af; querybuf *buf; const char *cp; char *bp, *ep; int n, size, type, len; + char abuf[MAXDNAME]; name = va_arg(ap, const char *); af = va_arg(ap, int); *(struct hostent **)rval = NULL; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return NS_UNAVAIL; } switch (af) { case AF_INET: size = INADDRSZ; type = T_A; break; case AF_INET6: size = IN6ADDRSZ; type = T_AAAA; break; default: h_errno = NETDB_INTERNAL; errno = EAFNOSUPPORT; return NS_UNAVAIL; } host.h_addrtype = af; host.h_length = size; /* * if there aren't any dots, it could be a user-level alias. * this is also done in res_query() since we are not the only * function that looks up host names. */ - if (!strchr(name, '.') && (cp = __hostalias(name))) + if (!strchr(name, '.') && + (cp = _res_hostalias(name, abuf, sizeof abuf))) name = cp; /* * disallow names consisting only of digits/dots, unless * they end in a dot. */ if (isdigit((unsigned char)name[0])) for (cp = name;; ++cp) { if (!*cp) { if (*--cp == '.') break; /* * All-numeric, no dot at the end. * Fake up a hostent as if we'd actually * done a lookup. */ if (inet_pton(af, name, host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } strncpy(hostbuf, name, MAXDNAME); hostbuf[MAXDNAME] = '\0'; bp = hostbuf + MAXDNAME; ep = hostbuf + sizeof hostbuf; host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; if (_res.options & RES_USE_INET6) _map_v4v6_hostent(&host, &bp, &ep); h_errno = NETDB_SUCCESS; *(struct hostent **)rval = &host; return NS_SUCCESS; } if (!isdigit((unsigned char)*cp) && *cp != '.') break; } if ((isxdigit((unsigned char)name[0]) && strchr(name, ':') != NULL) || name[0] == ':') for (cp = name;; ++cp) { if (!*cp) { if (*--cp == '.') break; /* * All-IPv6-legal, no dot at the end. * Fake up a hostent as if we'd actually * done a lookup. */ if (inet_pton(af, name, host_addr) <= 0) { h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } strncpy(hostbuf, name, MAXDNAME); hostbuf[MAXDNAME] = '\0'; bp = hostbuf + MAXDNAME; len = sizeof hostbuf - MAXDNAME; host.h_name = hostbuf; host.h_aliases = host_aliases; host_aliases[0] = NULL; h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; host.h_addr_list = h_addr_ptrs; h_errno = NETDB_SUCCESS; *(struct hostent **)rval = &host; return NS_SUCCESS; } if (!isxdigit((unsigned char)*cp) && *cp != ':' && *cp != '.') break; } if ((buf = malloc(sizeof(*buf))) == NULL) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } n = res_search(name, C_IN, type, buf->buf, sizeof(buf->buf)); if (n < 0) { free(buf); dprintf("res_search failed (%d)\n", n); return (0); } else if (n > sizeof(buf->buf)) { free(buf); dprintf("static buffer is too small (%d)\n", n); return (0); } *(struct hostent **)rval = gethostanswer(buf, n, name, type); free(buf); return (*(struct hostent **)rval != NULL) ? NS_SUCCESS : NS_NOTFOUND; } int _dns_gethostbyaddr(void *rval, void *cb_data, va_list ap) { const char *addr; /* XXX should have been def'd as u_char! */ int len, af; const u_char *uaddr; static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff }; static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 }; int n, size; querybuf *buf; struct hostent *hp; char qbuf[MAXDNAME+1], *qp; #ifdef SUNSECURITY struct hostent *rhp; char **haddr; u_long old_options; char hname2[MAXDNAME+1]; #endif /*SUNSECURITY*/ addr = va_arg(ap, const char *); uaddr = (const u_char *)addr; len = va_arg(ap, int); af = va_arg(ap, int); *(struct hostent **)rval = NULL; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return NS_UNAVAIL; } if (af == AF_INET6 && len == IN6ADDRSZ && (!bcmp(uaddr, mapped, sizeof mapped) || !bcmp(uaddr, tunnelled, sizeof tunnelled))) { /* Unmap. */ addr += sizeof mapped; uaddr += sizeof mapped; af = AF_INET; len = INADDRSZ; } switch (af) { case AF_INET: size = INADDRSZ; break; case AF_INET6: size = IN6ADDRSZ; break; default: errno = EAFNOSUPPORT; h_errno = NETDB_INTERNAL; return NS_UNAVAIL; } if (size != len) { errno = EINVAL; h_errno = NETDB_INTERNAL; return NS_UNAVAIL; } switch (af) { case AF_INET: (void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa", (uaddr[3] & 0xff), (uaddr[2] & 0xff), (uaddr[1] & 0xff), (uaddr[0] & 0xff)); break; case AF_INET6: qp = qbuf; for (n = IN6ADDRSZ - 1; n >= 0; n--) { qp += SPRINTF((qp, "%x.%x.", uaddr[n] & 0xf, (uaddr[n] >> 4) & 0xf)); } strlcat(qbuf, "ip6.arpa", sizeof(qbuf)); break; default: abort(); } if ((buf = malloc(sizeof(*buf))) == NULL) { h_errno = NETDB_INTERNAL; return NS_NOTFOUND; } n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf->buf, sizeof buf->buf); if (n < 0) { free(buf); dprintf("res_query failed (%d)\n", n); return NS_UNAVAIL; } if (n > sizeof buf->buf) { free(buf); dprintf("static buffer is too small (%d)\n", n); return NS_UNAVAIL; } if (!(hp = gethostanswer(buf, n, qbuf, T_PTR))) { free(buf); return NS_NOTFOUND; /* h_errno was set by gethostanswer() */ } free(buf); #ifdef SUNSECURITY if (af == AF_INET) { /* * turn off search as the name should be absolute, * 'localhost' should be matched by defnames */ strncpy(hname2, hp->h_name, MAXDNAME); hname2[MAXDNAME] = '\0'; old_options = _res.options; _res.options &= ~RES_DNSRCH; _res.options |= RES_DEFNAMES; if (!(rhp = gethostbyname(hname2))) { syslog(LOG_NOTICE|LOG_AUTH, "gethostbyaddr: No A record for %s (verifying [%s])", hname2, inet_ntoa(*((struct in_addr *)addr))); _res.options = old_options; h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } _res.options = old_options; for (haddr = rhp->h_addr_list; *haddr; haddr++) if (!memcmp(*haddr, addr, INADDRSZ)) break; if (!*haddr) { syslog(LOG_NOTICE|LOG_AUTH, "gethostbyaddr: A record of %s != PTR record [%s]", hname2, inet_ntoa(*((struct in_addr *)addr))); h_errno = HOST_NOT_FOUND; return NS_NOTFOUND; } } #endif /*SUNSECURITY*/ hp->h_addrtype = af; hp->h_length = len; bcopy(addr, host_addr, len); h_addr_ptrs[0] = (char *)host_addr; h_addr_ptrs[1] = NULL; if (af == AF_INET && (_res.options & RES_USE_INET6)) { _map_v4v6_address((char*)host_addr, (char*)host_addr); hp->h_addrtype = AF_INET6; hp->h_length = IN6ADDRSZ; } h_errno = NETDB_SUCCESS; *(struct hostent **)rval = hp; return (hp != NULL) ? NS_SUCCESS : NS_NOTFOUND; } #ifdef RESOLVSORT static void addrsort(ap, num) char **ap; int num; { int i, j; char **p; short aval[MAXADDRS]; int needsort = 0; p = ap; for (i = 0; i < num; i++, p++) { for (j = 0 ; (unsigned)j < _res.nsort; j++) if (_res.sort_list[j].addr.s_addr == (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask)) break; aval[i] = j; if (needsort == 0 && i > 0 && j < aval[i-1]) needsort = i; } if (!needsort) return; while (needsort < num) { for (j = needsort - 1; j >= 0; j--) { if (aval[j] > aval[j+1]) { char *hp; i = aval[j]; aval[j] = aval[j+1]; aval[j+1] = i; hp = ap[j]; ap[j] = ap[j+1]; ap[j+1] = hp; } else break; } needsort++; } } #endif void _sethostdnsent(stayopen) int stayopen; { if ((_res.options & RES_INIT) == 0 && res_init() == -1) return; if (stayopen) _res.options |= RES_STAYOPEN | RES_USEVC; } void _endhostdnsent() { _res.options &= ~(RES_STAYOPEN | RES_USEVC); res_close(); } Index: head/lib/libc/net/res_query.c =================================================================== --- head/lib/libc/net/res_query.c (revision 145112) +++ head/lib/libc/net/res_query.c (revision 145113) @@ -1,437 +1,447 @@ /*- * Copyright (c) 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Portions Copyright (c) 1993 by Digital Equipment Corporation. * * 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, and that * the name of Digital Equipment Corporation not be used in advertising or * publicity pertaining to distribution of the document or software without * specific, written prior permission. * * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT * CORPORATION 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. */ /* * Portions Copyright (c) 1996 by Internet Software Consortium. * * 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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE * CONSORTIUM 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. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)res_query.c 8.1 (Berkeley) 6/4/93"; static char rcsid[] = "$Id: res_query.c,v 8.14 1997/06/09 17:47:05 halley Exp $"; #endif /* LIBC_SCCS and not lint */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include "res_config.h" #if PACKETSZ > 1024 #define MAXPACKET PACKETSZ #else #define MAXPACKET 1024 #endif +const char *_res_hostalias(const char *, char *, size_t); + /* * Formulate a normal query, send, and await answer. * Returned answer is placed in supplied buffer "answer". * Perform preliminary check of answer, returning success only * if no error is indicated and the answer count is nonzero. * Return the size of the response on success, -1 on error. * Error number is left in h_errno. * * Caller must parse answer and determine whether it answers the question. */ int res_query(name, class, type, answer, anslen) const char *name; /* domain name */ int class, type; /* class and type of query */ u_char *answer; /* buffer to put answer */ int anslen; /* size of answer buffer */ { u_char buf[MAXPACKET]; HEADER *hp = (HEADER *) answer; int n; hp->rcode = NOERROR; /* default */ if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (-1); } #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query(%s, %d, %d)\n", name, class, type); #endif n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, buf, sizeof(buf)); if (n > 0 && (_res.options & RES_USE_EDNS0) != 0) n = res_opt(n, buf, sizeof(buf), anslen); if (n <= 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query: mkquery failed\n"); #endif h_errno = NO_RECOVERY; return (n); } n = res_send(buf, n, answer, anslen); if (n < 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_query: send error\n"); #endif h_errno = TRY_AGAIN; return (n); } if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) { #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; rcode = %d, ancount=%d\n", hp->rcode, ntohs(hp->ancount)); #endif switch (hp->rcode) { case NXDOMAIN: h_errno = HOST_NOT_FOUND; break; case SERVFAIL: h_errno = TRY_AGAIN; break; case NOERROR: h_errno = NO_DATA; break; case FORMERR: case NOTIMP: case REFUSED: default: h_errno = NO_RECOVERY; break; } return (-1); } return (n); } /* * Formulate a normal query, send, and retrieve answer in supplied buffer. * Return the size of the response on success, -1 on error. * If enabled, implement search rules until answer or unrecoverable failure * is detected. Error code, if any, is left in h_errno. */ int res_search(name, class, type, answer, anslen) const char *name; /* domain name */ int class, type; /* class and type of query */ u_char *answer; /* buffer to put answer */ int anslen; /* size of answer */ { const char *cp, * const *domain; + char tmp[MAXDNAME]; u_int dots; int trailing_dot, ret, saved_herrno; int got_nodata = 0, got_servfail = 0, tried_as_is = 0; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (-1); } errno = 0; h_errno = HOST_NOT_FOUND; /* default, if we never query */ dots = 0; for (cp = name; *cp; cp++) dots += (*cp == '.'); trailing_dot = 0; if (cp > name && *--cp == '.') trailing_dot++; /* If there aren't any dots, it could be a user-level alias */ - if (!dots && (cp = hostalias(name)) != NULL) + if (!dots && (cp = _res_hostalias(name, tmp, sizeof tmp)) != NULL) return (res_query(cp, class, type, answer, anslen)); /* * If there are dots in the name already, let's just give it a try * 'as is'. The threshold can be set with the "ndots" option. */ saved_herrno = -1; if (dots >= _res.ndots) { ret = res_querydomain(name, NULL, class, type, answer, anslen); if (ret > 0) return (ret); saved_herrno = h_errno; tried_as_is++; } /* * We do at least one level of search if * - there is no dot and RES_DEFNAME is set, or * - there is at least one dot, there is no trailing dot, * and RES_DNSRCH is set. */ if ((!dots && (_res.options & RES_DEFNAMES)) || (dots && !trailing_dot && (_res.options & RES_DNSRCH))) { int done = 0; for (domain = (const char * const *)_res.dnsrch; *domain && !done; domain++) { ret = res_querydomain(name, *domain, class, type, answer, anslen); if (ret > 0) return (ret); /* * If no server present, give up. * If name isn't found in this domain, * keep trying higher domains in the search list * (if that's enabled). * On a NO_DATA error, keep trying, otherwise * a wildcard entry of another type could keep us * from finding this entry higher in the domain. * If we get some other error (negative answer or * server failure), then stop searching up, * but try the input name below in case it's * fully-qualified. */ if (errno == ECONNREFUSED) { h_errno = TRY_AGAIN; return (-1); } switch (h_errno) { case NO_DATA: got_nodata++; /* FALLTHROUGH */ case HOST_NOT_FOUND: /* keep trying */ break; case TRY_AGAIN: /* * This can occur due to a server failure * (that is, all listed servers have failed), * or all listed servers have timed out. * ((HEADER *)answer)->rcode may not be set * to SERVFAIL in the case of a timeout. * * Either way we must terminate the search * and return TRY_AGAIN in order to avoid * non-deterministic return codes. For * example, loaded name servers or races * against network startup/validation (dhcp, * ppp, etc) can cause the search to timeout * on one search element, e.g. 'fu.bar.com', * and return a definitive failure on the * next search element, e.g. 'fu.'. */ ++got_servfail; /* FALLTHROUGH */ default: /* anything else implies that we're done */ done++; } /* if we got here for some reason other than DNSRCH, * we only wanted one iteration of the loop, so stop. */ if (!(_res.options & RES_DNSRCH)) done++; } } /* * If we have not already tried the name "as is", do that now. * note that we do this regardless of how many dots were in the * name or whether it ends with a dot unless NOTLDQUERY is set. */ if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) { ret = res_querydomain(name, NULL, class, type, answer, anslen); if (ret > 0) return (ret); } /* if we got here, we didn't satisfy the search. * if we did an initial full query, return that query's h_errno * (note that we wouldn't be here if that query had succeeded). * else if we ever got a nodata, send that back as the reason. * else send back meaningless h_errno, that being the one from * the last DNSRCH we did. */ if (saved_herrno != -1) h_errno = saved_herrno; else if (got_nodata) h_errno = NO_DATA; else if (got_servfail) h_errno = TRY_AGAIN; return (-1); } /* * Perform a call on res_query on the concatenation of name and domain, * removing a trailing dot from name if domain is NULL. */ int res_querydomain(name, domain, class, type, answer, anslen) const char *name, *domain; int class, type; /* class and type of query */ u_char *answer; /* buffer to put answer */ int anslen; /* size of answer */ { char nbuf[MAXDNAME]; const char *longname = nbuf; int n, d; if ((_res.options & RES_INIT) == 0 && res_init() == -1) { h_errno = NETDB_INTERNAL; return (-1); } #ifdef DEBUG if (_res.options & RES_DEBUG) printf(";; res_querydomain(%s, %s, %d, %d)\n", name, domain?domain:"", class, type); #endif if (domain == NULL) { /* * Check for trailing '.'; * copy without '.' if present. */ n = strlen(name); if (n >= MAXDNAME) { h_errno = NO_RECOVERY; return (-1); } n--; if (n >= 0 && name[n] == '.') { strncpy(nbuf, name, n); nbuf[n] = '\0'; } else longname = name; } else { n = strlen(name); d = strlen(domain); if (n + d + 1 >= MAXDNAME) { h_errno = NO_RECOVERY; return (-1); } sprintf(nbuf, "%s.%s", name, domain); } return (res_query(longname, class, type, answer, anslen)); } const char * -hostalias(name) - const char *name; +_res_hostalias(const char *name, char *dst, size_t siz) { - char *cp1, *cp2; - FILE *fp; - char *file; + char *file, *cp1, *cp2; char buf[BUFSIZ]; - static char abuf[MAXDNAME]; + FILE *fp; if (_res.options & RES_NOALIASES) return (NULL); if (issetugid()) return (NULL); file = getenv("HOSTALIASES"); if (file == NULL || (fp = fopen(file, "r")) == NULL) return (NULL); setbuf(fp, NULL); buf[sizeof(buf) - 1] = '\0'; while (fgets(buf, sizeof(buf), fp)) { for (cp1 = buf; *cp1 && !isspace((unsigned char)*cp1); ++cp1) ; if (!*cp1) break; *cp1 = '\0'; if (!strcasecmp(buf, name)) { while (isspace((unsigned char)*++cp1)) ; if (!*cp1) break; - for (cp2 = cp1 + 1; *cp2 && !isspace((unsigned char)*cp2); ++cp2) + for (cp2 = cp1 + 1; *cp2 && + !isspace((unsigned char)*cp2); ++cp2) ; - abuf[sizeof(abuf) - 1] = *cp2 = '\0'; - strncpy(abuf, cp1, sizeof(abuf) - 1); + *cp2 = '\0'; + strncpy(dst, cp1, siz - 1); + dst[siz - 1] = '\0'; fclose(fp); - return (abuf); + return (dst); } } fclose(fp); return (NULL); +} + +const char * +hostalias(const char *name) +{ + static char abuf[MAXDNAME]; + + return (_res_hostalias(name, abuf, sizeof abuf)); } /* * Weak aliases for applications that use certain private entry points, * and fail to include . */ #undef res_query __weak_reference(__res_query, res_query); #undef res_search __weak_reference(__res_search, res_search); #undef res_querydomain __weak_reference(__res_querydomain, res_querydomain);