/* $NetBSD: getnameinfo.c,v 1.1.1.1 2009/04/12 15:33:39 christos Exp $ */ /* * Issues to be discussed: * - Thread safe-ness must be checked */ #if ( defined(__linux__) || defined(__linux) || defined(LINUX) ) #ifndef IF_NAMESIZE # ifdef IFNAMSIZ # define IF_NAMESIZE IFNAMSIZ # else # define IF_NAMESIZE 16 # endif #endif #endif /* * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by WIDE Project and * its contributors. * 4. 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 /*% * Note that a_off will be dynamically adjusted so that to be consistent * with the definition of sockaddr_in{,6}. * The value presented below is just a guess. */ static struct afd { int a_af; int a_addrlen; size_t a_socklen; int a_off; } afdl [] = { /* first entry is linked last... */ {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), offsetof(struct sockaddr_in, sin_addr)}, {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), offsetof(struct sockaddr_in6, sin6_addr)}, {0, 0, 0, 0}, }; struct sockinet { #ifdef HAVE_SA_LEN u_char si_len; #endif u_char si_family; u_short si_port; }; static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *, size_t, int)); #ifdef HAVE_SIN6_SCOPE_ID static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t, int)); #endif int getnameinfo(sa, salen, host, hostlen, serv, servlen, flags) const struct sockaddr *sa; size_t salen; char *host; size_t hostlen; char *serv; size_t servlen; int flags; { struct afd *afd; struct servent *sp; struct hostent *hp; u_short port; #ifdef HAVE_SA_LEN size_t len; #endif int family, i; const char *addr; char *p; char numserv[512]; char numaddr[512]; const struct sockaddr_in6 *sin6; if (sa == NULL) return EAI_FAIL; #ifdef HAVE_SA_LEN len = sa->sa_len; if (len != salen) return EAI_FAIL; #endif family = sa->sa_family; for (i = 0; afdl[i].a_af; i++) if (afdl[i].a_af == family) { afd = &afdl[i]; goto found; } return EAI_FAMILY; found: if (salen != afd->a_socklen) return EAI_FAIL; port = ((const struct sockinet *)sa)->si_port; /*%< network byte order */ addr = (const char *)sa + afd->a_off; if (serv == NULL || servlen == 0U) { /* * rfc2553bis says that serv == NULL or servlen == 0 means that * the caller does not want the result. */ } else if (flags & NI_NUMERICSERV) { sprintf(numserv, "%d", ntohs(port)); if (strlen(numserv) > servlen) return EAI_MEMORY; strcpy(serv, numserv); } else { sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp"); if (sp) { if (strlen(sp->s_name) + 1 > servlen) return EAI_MEMORY; strcpy(serv, sp->s_name); } else return EAI_NONAME; } switch (sa->sa_family) { case AF_INET: if (ntohl(*(const u_int32_t *)addr) >> IN_CLASSA_NSHIFT == 0) flags |= NI_NUMERICHOST; break; case AF_INET6: sin6 = (const struct sockaddr_in6 *)sa; switch (sin6->sin6_addr.s6_addr[0]) { case 0x00: if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) ; else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) ; else flags |= NI_NUMERICHOST; break; default: if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) flags |= NI_NUMERICHOST; else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) flags |= NI_NUMERICHOST; break; } break; } if (host == NULL || hostlen == 0U) { /* * rfc2553bis says that host == NULL or hostlen == 0 means that * the caller does not want the result. */ } else if (flags & NI_NUMERICHOST) { goto numeric; } else { hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); if (hp) { if (flags & NI_NOFQDN) { p = strchr(hp->h_name, '.'); if (p) *p = '\0'; } if (strlen(hp->h_name) + 1 > hostlen) return EAI_MEMORY; strcpy(host, hp->h_name); } else { if (flags & NI_NAMEREQD) return EAI_NONAME; numeric: switch(afd->a_af) { case AF_INET6: { int error; if ((error = ip6_parsenumeric(sa, addr, host, hostlen, flags)) != 0) return(error); break; } default: if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) == NULL) return EAI_NONAME; if (strlen(numaddr) + 1 > hostlen) return EAI_MEMORY; strcpy(host, numaddr); } } } return(0); } static int ip6_parsenumeric(const struct sockaddr *sa, const char *addr, char *host, size_t hostlen, int flags) { size_t numaddrlen; char numaddr[512]; #ifndef HAVE_SIN6_SCOPE_ID UNUSED(sa); UNUSED(flags); #endif if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr)) == NULL) return EAI_SYSTEM; numaddrlen = strlen(numaddr); if (numaddrlen + 1 > hostlen) /*%< don't forget terminator */ return EAI_MEMORY; strcpy(host, numaddr); #ifdef HAVE_SIN6_SCOPE_ID if (((const struct sockaddr_in6 *)sa)->sin6_scope_id) { char scopebuf[MAXHOSTNAMELEN]; /*%< XXX */ int scopelen; /* ip6_sa2str never fails */ scopelen = ip6_sa2str((const struct sockaddr_in6 *)sa, scopebuf, sizeof(scopebuf), flags); if (scopelen + 1 + numaddrlen + 1 > hostlen) return EAI_MEMORY; /* construct */ memcpy(host + numaddrlen + 1, scopebuf, scopelen); host[numaddrlen] = SCOPE_DELIMITER; host[numaddrlen + 1 + scopelen] = '\0'; } #endif return 0; } #ifdef HAVE_SIN6_SCOPE_ID /* ARGSUSED */ static int ip6_sa2str(const struct sockaddr_in6 *sa6, char *buf, size_t bufsiz, int flags) { #ifdef USE_IFNAMELINKID unsigned int ifindex = (unsigned int)sa6->sin6_scope_id; const struct in6_addr *a6 = &sa6->sin6_addr; #endif char tmp[64]; #ifdef NI_NUMERICSCOPE if (flags & NI_NUMERICSCOPE) { sprintf(tmp, "%u", sa6->sin6_scope_id); if (bufsiz != 0U) { strncpy(buf, tmp, bufsiz - 1); buf[bufsiz - 1] = '\0'; } return(strlen(tmp)); } #endif #ifdef USE_IFNAMELINKID /* * For a link-local address, convert the index to an interface * name, assuming a one-to-one mapping between links and interfaces. * Note, however, that this assumption is stronger than the * specification of the scoped address architecture; the * specficication says that more than one interfaces can belong to * a single link. */ /* if_indextoname() does not take buffer size. not a good api... */ if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) && bufsiz >= IF_NAMESIZE) { char *p = if_indextoname(ifindex, buf); if (p) { return(strlen(p)); } } #endif /* last resort */ sprintf(tmp, "%u", sa6->sin6_scope_id); if (bufsiz != 0U) { strncpy(buf, tmp, bufsiz - 1); buf[bufsiz - 1] = '\0'; } return(strlen(tmp)); } #endif /*! \file */