/* * 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. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "addrinfo.h" #define SUCCESS 0 #define ANY 0 #define YES 1 #define NO 0 static const char in_addrany[] = { 0, 0, 0, 0 }; static const char in6_addrany[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; static const char in_loopback[] = { 127, 0, 0, 1 }; static const char in6_loopback[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 }; struct sockinet { u_char si_len; u_char si_family; u_short si_port; }; static struct afd { int a_af; int a_addrlen; int a_socklen; int a_off; const char *a_addrany; const char *a_loopback; } 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}, #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, NULL, NULL}, }; #ifdef INET6 #define PTON_MAX 16 #else #define PTON_MAX 4 #endif static int get_name(const char *, struct afd *, struct addrinfo **, char *, struct addrinfo *, int); static int get_addr(const char *, int, struct addrinfo **, struct addrinfo *, int); static int get_addr0(const char *, int, struct addrinfo **, struct addrinfo *, int); static int str_isnumber(const char *); static char *ai_errlist[] = { "Success", "Address family for hostname not supported", /* EAI_ADDRFAMILY */ "Temporary failure in name resolution", /* EAI_AGAIN */ "Invalid value for ai_flags", /* EAI_BADFLAGS */ "Non-recoverable failure in name resolution", /* EAI_FAIL */ "ai_family not supported", /* EAI_FAMILY */ "Memory allocation failure", /* EAI_MEMORY */ "No address associated with hostname", /* EAI_NODATA */ "hostname nor servname provided, or not known",/* EAI_NONAME */ "servname not supported for ai_socktype", /* EAI_SERVICE */ "ai_socktype not supported", /* EAI_SOCKTYPE */ "System error returned in errno", /* EAI_SYSTEM */ "Invalid value for hints", /* EAI_BADHINTS */ "Resolved protocol is unknown", /* EAI_PROTOCOL */ "Unknown error", /* EAI_MAX */ }; #define GET_CANONNAME(ai, str) \ if (pai->ai_flags & AI_CANONNAME) {\ if (((ai)->ai_canonname = (char *)malloc(strlen(str) + 1)) != NULL) {\ strcpy((ai)->ai_canonname, (str));\ } else {\ error = EAI_MEMORY;\ goto free;\ }\ } #ifdef HAVE_SA_LEN #define SET_AILEN(ai,l) (ai)->ai_addr->sa_len = (ai)->ai_addrlen = (l) #else #define SET_AILEN(ai,l) (ai)->ai_addrlen = (l) #endif #define GET_AI(ai, afd, addr, port) {\ char *p;\ if (((ai) = (struct addrinfo *)malloc(sizeof(struct addrinfo) +\ ((afd)->a_socklen)))\ == NULL) {\ error = EAI_MEMORY;\ goto free;\ }\ memcpy(ai, pai, sizeof(struct addrinfo));\ (ai)->ai_addr = (struct sockaddr *)((ai) + 1);\ memset((ai)->ai_addr, 0, (afd)->a_socklen);\ SET_AILEN((ai), (afd)->a_socklen);\ (ai)->ai_addr->sa_family = (ai)->ai_family = (afd)->a_af;\ ((struct sockinet *)(ai)->ai_addr)->si_port = port;\ p = (char *)((ai)->ai_addr);\ memcpy(p + (afd)->a_off, (addr), (afd)->a_addrlen);\ } #define ERR(err) { error = (err); goto bad; } char * gai_strerror(ecode) int ecode; { if (ecode < 0 || ecode > EAI_MAX) ecode = EAI_MAX; return ai_errlist[ecode]; } 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); } while ((ai = next) != NULL); } static int str_isnumber(p) const char *p; { char *q = (char *)p; while (*q) { if (! isdigit(*q)) return NO; q++; } return YES; } int getaddrinfo(hostname, servname, hints, res) const char *hostname, *servname; const struct addrinfo *hints; struct addrinfo **res; { struct addrinfo sentinel; struct addrinfo *top = NULL; struct addrinfo *cur; int i, error = 0; char pton[PTON_MAX]; struct addrinfo ai; struct addrinfo *pai; u_short port; /* initialize file static vars */ sentinel.ai_next = NULL; 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; port = ANY; 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)); switch (pai->ai_socktype) { case ANY: switch (pai->ai_protocol) { case ANY: break; case IPPROTO_UDP: pai->ai_socktype = SOCK_DGRAM; break; case IPPROTO_TCP: pai->ai_socktype = SOCK_STREAM; break; default: pai->ai_socktype = SOCK_RAW; break; } break; case SOCK_RAW: break; case SOCK_DGRAM: if (pai->ai_protocol != IPPROTO_UDP && pai->ai_protocol != ANY) ERR(EAI_BADHINTS); /*xxx*/ pai->ai_protocol = IPPROTO_UDP; break; case SOCK_STREAM: if (pai->ai_protocol != IPPROTO_TCP && pai->ai_protocol != ANY) ERR(EAI_BADHINTS); /*xxx*/ pai->ai_protocol = IPPROTO_TCP; break; default: ERR(EAI_SOCKTYPE); break; } } /* * service port */ if (servname) { if (str_isnumber(servname)) { if (pai->ai_socktype == ANY) { /* caller accept *ANY* socktype */ pai->ai_socktype = SOCK_DGRAM; pai->ai_protocol = IPPROTO_UDP; } port = htons(atoi(servname)); } else { struct servent *sp; char *proto; proto = NULL; switch (pai->ai_socktype) { case ANY: proto = NULL; break; case SOCK_DGRAM: proto = "udp"; break; case SOCK_STREAM: proto = "tcp"; break; default: fprintf(stderr, "panic!\n"); break; } if ((sp = getservbyname(servname, proto)) == NULL) ERR(EAI_SERVICE); port = sp->s_port; if (pai->ai_socktype == ANY) { if (strcmp(sp->s_proto, "udp") == 0) { pai->ai_socktype = SOCK_DGRAM; pai->ai_protocol = IPPROTO_UDP; } else if (strcmp(sp->s_proto, "tcp") == 0) { pai->ai_socktype = SOCK_STREAM; pai->ai_protocol = IPPROTO_TCP; } else ERR(EAI_PROTOCOL); /*xxx*/ } } } /* * hostname == NULL. * passive socket -> anyaddr (0.0.0.0 or ::) * non-passive socket -> localhost (127.0.0.1 or ::1) */ if (hostname == NULL) { struct afd *afd; int s; for (afd = &afdl[0]; afd->a_af; afd++) { if (!(pai->ai_family == PF_UNSPEC || pai->ai_family == afd->a_af)) { continue; } /* * filter out AFs that are not supported by the kernel * XXX errno? */ s = socket(afd->a_af, SOCK_DGRAM, 0); if (s < 0) continue; close(s); if (pai->ai_flags & AI_PASSIVE) { GET_AI(cur->ai_next, afd, afd->a_addrany, port); /* xxx meaningless? * GET_CANONNAME(cur->ai_next, "anyaddr"); */ } else { GET_AI(cur->ai_next, afd, afd->a_loopback, port); /* xxx meaningless? * GET_CANONNAME(cur->ai_next, "localhost"); */ } cur = cur->ai_next; } top = sentinel.ai_next; if (top) goto good; else ERR(EAI_FAMILY); } /* hostname as numeric name */ for (i = 0; afdl[i].a_af; i++) { if (inet_pton(afdl[i].a_af, hostname, pton) == 1) { u_long v4a; u_char pfx; switch (afdl[i].a_af) { case AF_INET: v4a = ntohl(((struct in_addr *)pton)->s_addr); if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) pai->ai_flags &= ~AI_CANONNAME; v4a >>= IN_CLASSA_NSHIFT; if (v4a == 0 || v4a == IN_LOOPBACKNET) pai->ai_flags &= ~AI_CANONNAME; break; #ifdef INET6 case AF_INET6: pfx = ((struct in6_addr *)pton)->s6_addr[0]; if (pfx == 0 || pfx == 0xfe || pfx == 0xff) pai->ai_flags &= ~AI_CANONNAME; break; #endif } if (pai->ai_family == afdl[i].a_af || pai->ai_family == PF_UNSPEC) { if (! (pai->ai_flags & AI_CANONNAME)) { GET_AI(top, &afdl[i], pton, port); goto good; } /* * if AI_CANONNAME and if reverse lookup * fail, return ai anyway to pacify * calling application. * * XXX getaddrinfo() is a name->address * translation function, and it looks strange * that we do addr->name translation here. */ get_name(pton, &afdl[i], &top, pton, pai, port); goto good; } else ERR(EAI_FAMILY); /*xxx*/ } } if (pai->ai_flags & AI_NUMERICHOST) ERR(EAI_NONAME); /* hostname as alphabetical name */ error = get_addr(hostname, pai->ai_family, &top, pai, port); if (error == 0) { if (top) { good: *res = top; return SUCCESS; } else error = EAI_FAIL; } free: if (top) freeaddrinfo(top); bad: *res = NULL; return error; } static int get_name(addr, afd, res, numaddr, pai, port0) const char *addr; struct afd *afd; struct addrinfo **res; char *numaddr; struct addrinfo *pai; int port0; { u_short port = port0 & 0xffff; struct hostent *hp; struct addrinfo *cur; int error = 0; hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) { GET_AI(cur, afd, hp->h_addr_list[0], port); GET_CANONNAME(cur, hp->h_name); } else GET_AI(cur, afd, numaddr, port); *res = cur; return SUCCESS; free: if (cur) freeaddrinfo(cur); /* bad: */ *res = NULL; return error; } static int get_addr(hostname, af, res0, pai, port0) const char *hostname; int af; struct addrinfo **res0; struct addrinfo *pai; int port0; { int i, error, ekeep; struct addrinfo *cur; struct addrinfo **res; int retry; int s; res = res0; ekeep = 0; error = 0; for (i = 0; afdl[i].a_af; i++) { retry = 0; if (af == AF_UNSPEC) { /* * filter out AFs that are not supported by the kernel * XXX errno? */ s = socket(afdl[i].a_af, SOCK_DGRAM, 0); if (s < 0) continue; close(s); } else { if (af != afdl[i].a_af) continue; } /* It is WRONG, we need getipnodebyname(). */ again: error = get_addr0(hostname, afdl[i].a_af, res, pai, port0); switch (error) { case EAI_AGAIN: if (++retry < 3) goto again; /* FALL THROUGH*/ default: if (ekeep == 0) ekeep = error; break; } if (*res) { /* make chain of addrs */ for (cur = *res; cur && cur->ai_next; cur = cur->ai_next) ; if (!cur) return EAI_FAIL; res = &cur->ai_next; } } /* if we got something, it's okay */ if (*res0) return 0; return error ? error : ekeep; } static int get_addr0(hostname, af, res, pai, port0) const char *hostname; int af; struct addrinfo **res; struct addrinfo *pai; int port0; { u_short port = port0 & 0xffff; struct addrinfo sentinel; struct hostent *hp; struct addrinfo *top, *cur; struct afd *afd; int i, error = 0, h_error; char *ap; top = NULL; sentinel.ai_next = NULL; cur = &sentinel; #ifdef HAVE_GETHOSTBYNAME2 if (af == AF_UNSPEC) { error = EAI_FAIL; goto bad; } hp = gethostbyname2(hostname, af); #else if (af != AF_UNSPEC && af != AF_INET) { error = EAI_FAIL; goto bad; } hp = gethostbyname(hostname); #endif h_error = h_errno; if (hp == NULL) { switch (h_error) { case HOST_NOT_FOUND: case NO_DATA: error = EAI_NODATA; break; case TRY_AGAIN: error = EAI_AGAIN; break; case NO_RECOVERY: case NETDB_INTERNAL: default: error = EAI_FAIL; break; } goto bad; } if ((hp->h_name == NULL) || (hp->h_name[0] == 0) || (hp->h_addr_list[0] == NULL)) ERR(EAI_FAIL); for (i = 0; (ap = hp->h_addr_list[i]) != NULL; i++) { switch (af) { #ifdef INET6 case AF_INET6: afd = &afdl[N_INET6]; break; #endif #ifndef INET6 default: /* AF_UNSPEC */ #endif case AF_INET: afd = &afdl[N_INET]; break; #ifdef INET6 default: /* AF_UNSPEC */ if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { ap += sizeof(struct in6_addr) - sizeof(struct in_addr); afd = &afdl[N_INET]; } else afd = &afdl[N_INET6]; break; #endif } GET_AI(cur->ai_next, afd, ap, port); if (cur == &sentinel) { top = cur->ai_next; GET_CANONNAME(top, hp->h_name); } cur = cur->ai_next; } *res = top; return SUCCESS; free: if (top) freeaddrinfo(top); bad: *res = NULL; return error; }