/* $NetBSD: getnameinfo.c,v 1.23 2000/09/25 23:37:55 itojun Exp $ */ /* $KAME: getnameinfo.c,v 1.45 2000/09/25 22:43:56 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. */ /* * Issues to be discussed: * - Thread safe-ness must be checked * - RFC2553 says that we should raise error on short buffer. X/Open says * we need to truncate the result. We obey RFC2553 (and X/Open should be * modified). ipngwg rough consensus seems to follow RFC2553. * - What is "local" in NI_FQDN? * - NI_NAMEREQD and NI_NUMERICHOST conflict with each other. * - (KAME extension) NI_WITHSCOPEID when called with global address, * and sin6_scope_id filled */ #include #if defined(LIBC_SCCS) && !defined(lint) __RCSID("$NetBSD: getnameinfo.c,v 1.23 2000/09/25 23:37:55 itojun Exp $"); #endif /* LIBC_SCCS and not lint */ #include "namespace.h" #include #include #include #include #include #include #include #include #include #include #ifdef __weak_alias __weak_alias(getnameinfo,_getnameinfo) #endif #define SUCCESS 0 #define ANY 0 #define YES 1 #define NO 0 static struct afd { int a_af; int a_addrlen; int a_socklen; int a_off; } afdl [] = { #ifdef INET6 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), offsetof(struct sockaddr_in6, sin6_addr)}, #endif {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), offsetof(struct sockaddr_in, sin_addr)}, {0, 0, 0}, }; struct sockinet { u_char si_len; u_char si_family; u_short si_port; }; #ifdef INET6 static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *, size_t, int)); static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t, int)); #endif /* 2553bis: use EAI_xx for getnameinfo */ #define ENI_NOSOCKET EAI_FAIL /*XXX*/ #define ENI_NOSERVNAME EAI_NONAME #define ENI_NOHOSTNAME EAI_NONAME #define ENI_MEMORY EAI_MEMORY #define ENI_SYSTEM EAI_SYSTEM #define ENI_FAMILY EAI_FAMILY #define ENI_SALEN EAI_FAMILY int getnameinfo(sa, salen, host, hostlen, serv, servlen, flags) const struct sockaddr *sa; socklen_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; int family, i; const char *addr; u_int32_t v4a; char numserv[512]; char numaddr[512]; if (sa == NULL) return ENI_NOSOCKET; #ifdef BSD4_4 if (sa->sa_len != salen) return ENI_SALEN; #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 ENI_FAMILY; found: if (salen != afd->a_socklen) return ENI_SALEN; /* network byte order */ port = ((const struct sockinet *)(const void *)sa)->si_port; addr = (const char *)(const void *)sa + afd->a_off; if (serv == NULL || servlen == 0) { /* * do nothing in this case. * in case you are wondering if "&&" is more correct than * "||" here: RFC2553 says that serv == NULL OR servlen == 0 * means that the caller does not want the result. */ } else { if (flags & NI_NUMERICSERV) sp = NULL; else { sp = getservbyport(port, (flags & NI_DGRAM) ? "udp" : "tcp"); } if (sp) { if (strlen(sp->s_name) + 1 > servlen) return ENI_MEMORY; strcpy(serv, sp->s_name); } else { snprintf(numserv, sizeof(numserv), "%d", ntohs(port)); if (strlen(numserv) + 1 > servlen) return ENI_MEMORY; strcpy(serv, numserv); } } switch (sa->sa_family) { case AF_INET: v4a = (u_int32_t) ntohl(((const struct sockaddr_in *) (const void *)sa)->sin_addr.s_addr); if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) flags |= NI_NUMERICHOST; v4a >>= IN_CLASSA_NSHIFT; if (v4a == 0) flags |= NI_NUMERICHOST; break; #ifdef INET6 case AF_INET6: { const struct sockaddr_in6 *sin6; sin6 = (const struct sockaddr_in6 *)(const void *)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; #endif } if (host == NULL || hostlen == 0) { /* * do nothing in this case. * in case you are wondering if "&&" is more correct than * "||" here: RFC2553 says that host == NULL OR hostlen == 0 * means that the caller does not want the result. */ } else if (flags & NI_NUMERICHOST) { int numaddrlen; /* NUMERICHOST and NAMEREQD conflicts with each other */ if (flags & NI_NAMEREQD) return ENI_NOHOSTNAME; switch(afd->a_af) { #ifdef INET6 case AF_INET6: { int error; if ((error = ip6_parsenumeric(sa, addr, host, hostlen, flags)) != 0) return(error); break; } #endif default: if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) == NULL) return ENI_SYSTEM; numaddrlen = strlen(numaddr); if (numaddrlen + 1 > hostlen) /* don't forget terminator */ return ENI_MEMORY; strcpy(host, numaddr); break; } } else { hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); if (hp) { #if 0 /* * commented out, since "for local host" is not * implemented here - see RFC2553 p30 */ if (flags & NI_NOFQDN) { char *p; p = strchr(hp->h_name, '.'); if (p) *p = '\0'; } #endif if (strlen(hp->h_name) + 1 > hostlen) { return ENI_MEMORY; } strcpy(host, hp->h_name); } else { if (flags & NI_NAMEREQD) return ENI_NOHOSTNAME; switch(afd->a_af) { #ifdef INET6 case AF_INET6: { int error; if ((error = ip6_parsenumeric(sa, addr, host, hostlen, flags)) != 0) return(error); break; } #endif default: if (inet_ntop(afd->a_af, addr, host, hostlen) == NULL) return ENI_SYSTEM; break; } } } return SUCCESS; } #ifdef INET6 static int ip6_parsenumeric(sa, addr, host, hostlen, flags) const struct sockaddr *sa; const char *addr; char *host; size_t hostlen; int flags; { int numaddrlen; char numaddr[512]; if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr)) == NULL) return ENI_SYSTEM; numaddrlen = strlen(numaddr); if (numaddrlen + 1 > hostlen) /* don't forget terminator */ return ENI_MEMORY; strcpy(host, numaddr); #ifdef NI_WITHSCOPEID if (((const struct sockaddr_in6 *)(const void *)sa)->sin6_scope_id) { if (flags & NI_WITHSCOPEID) { char scopebuf[MAXHOSTNAMELEN]; int scopelen; /* ip6_sa2str never fails */ scopelen = ip6_sa2str( (const struct sockaddr_in6 *)(const void *)sa, scopebuf, sizeof(scopebuf), 0); if (scopelen + 1 + numaddrlen + 1 > hostlen) return ENI_MEMORY; /* * construct */ memcpy(host + numaddrlen + 1, scopebuf, (size_t)scopelen); host[numaddrlen] = SCOPE_DELIMITER; host[numaddrlen + 1 + scopelen] = '\0'; } } #endif /* NI_WITHSCOPEID */ return 0; } /* ARGSUSED */ static int ip6_sa2str(sa6, buf, bufsiz, flags) const struct sockaddr_in6 *sa6; char *buf; size_t bufsiz; int flags; { unsigned int ifindex = (unsigned int)sa6->sin6_scope_id; const struct in6_addr *a6 = &sa6->sin6_addr; #ifdef notyet if (flags & NI_NUMERICSCOPE) { return(snprintf(buf, bufsiz, "%d", sa6->sin6_scope_id)); } #endif /* 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)); } } /* last resort */ return(snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id)); } #endif /* INET6 */