/* $KAME: getnameinfo.c,v 1.61 2002/06/27 09:25:47 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * Copyright (c) 2000 Ben Harris. * 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) always attach textual scopeid (fe80::1%lo0), if * sin6_scope_id is filled - standardization status? * XXX breaks backward compat for code that expects no scopeid. * beware on merge. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static const struct afd *find_afd(int); static int getnameinfo_inet(const struct afd *, const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int); #ifdef INET6 static int ip6_parsenumeric(const struct sockaddr *, const char *, char *, size_t, int); static int ip6_sa2str(const struct sockaddr_in6 *, char *, size_t, int); #endif static int getnameinfo_link(const struct afd *, const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int); static int hexname(const u_int8_t *, size_t, char *, size_t); static int getnameinfo_un(const struct afd *, const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int); static const struct afd { int a_af; size_t a_addrlen; socklen_t a_socklen; int a_off; int (*a_func)(const struct afd *, const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int); } afdl [] = { #ifdef INET6 {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), offsetof(struct sockaddr_in6, sin6_addr), getnameinfo_inet}, #endif {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), offsetof(struct sockaddr_in, sin_addr), getnameinfo_inet}, #define sizeofmember(type, member) (sizeof(((type *)0)->member)) {PF_LOCAL, sizeofmember(struct sockaddr_un, sun_path), sizeof(struct sockaddr_un), offsetof(struct sockaddr_un, sun_path), getnameinfo_un}, {PF_LINK, sizeofmember(struct sockaddr_dl, sdl_data), sizeof(struct sockaddr_dl), offsetof(struct sockaddr_dl, sdl_data), getnameinfo_link}, {0, 0, 0}, }; int getnameinfo(const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) { const struct afd *afd; if (sa == NULL) return (EAI_FAIL); afd = find_afd(sa->sa_family); if (afd == NULL) return (EAI_FAMILY); switch (sa->sa_family) { case PF_LOCAL: /* * PF_LOCAL uses variable sa->sa_len depending on the * content length of sun_path. Require 1 byte in * sun_path at least. */ if (salen > afd->a_socklen || salen <= afd->a_socklen - sizeofmember(struct sockaddr_un, sun_path)) return (EAI_FAIL); break; case PF_LINK: if (salen <= afd->a_socklen - sizeofmember(struct sockaddr_dl, sdl_data)) return (EAI_FAIL); break; default: if (salen != afd->a_socklen) return (EAI_FAIL); break; } return ((*afd->a_func)(afd, sa, salen, host, hostlen, serv, servlen, flags)); } static const struct afd * find_afd(int af) { const struct afd *afd; if (af == PF_UNSPEC) return (NULL); for (afd = &afdl[0]; afd->a_af > 0; afd++) { if (afd->a_af == af) return (afd); } return (NULL); } static int getnameinfo_inet(const struct afd *afd, const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) { struct servent *sp; struct hostent *hp; u_short port; const char *addr; u_int32_t v4a; int h_error; char numserv[512]; char numaddr[512]; /* network byte order */ port = ((const struct sockaddr_in *)sa)->sin_port; addr = (const char *)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: rfc2553bis-03 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 EAI_MEMORY; strlcpy(serv, sp->s_name, servlen); } else { snprintf(numserv, sizeof(numserv), "%u", ntohs(port)); if (strlen(numserv) + 1 > servlen) return EAI_MEMORY; strlcpy(serv, numserv, servlen); } } switch (sa->sa_family) { case AF_INET: v4a = (u_int32_t) ntohl(((const struct sockaddr_in *)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 *)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: rfc2553bis-03 says that host == NULL or * hostlen == 0 means that the caller does not want the result. */ } else if (flags & NI_NUMERICHOST) { size_t numaddrlen; /* NUMERICHOST and NAMEREQD conflicts with each other */ if (flags & NI_NAMEREQD) return EAI_NONAME; 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 EAI_SYSTEM; numaddrlen = strlen(numaddr); if (numaddrlen + 1 > hostlen) /* don't forget terminator */ return EAI_MEMORY; strlcpy(host, numaddr, hostlen); break; } } else { hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 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) { freehostent(hp); return EAI_MEMORY; } strlcpy(host, hp->h_name, hostlen); freehostent(hp); } else { if (flags & NI_NAMEREQD) return EAI_NONAME; 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 EAI_SYSTEM; break; } } } return(0); } #ifdef INET6 static int ip6_parsenumeric(const struct sockaddr *sa, const char *addr, char *host, size_t hostlen, int flags) { size_t numaddrlen; char numaddr[512]; 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_OVERFLOW; strlcpy(host, numaddr, hostlen); if (((const struct sockaddr_in6 *)sa)->sin6_scope_id) { char zonebuf[MAXHOSTNAMELEN]; int zonelen; zonelen = ip6_sa2str( (const struct sockaddr_in6 *)(const void *)sa, zonebuf, sizeof(zonebuf), flags); if (zonelen < 0) return EAI_OVERFLOW; if (zonelen + 1 + numaddrlen + 1 > hostlen) return EAI_OVERFLOW; /* construct */ memcpy(host + numaddrlen + 1, zonebuf, (size_t)zonelen); host[numaddrlen] = SCOPE_DELIMITER; host[numaddrlen + 1 + zonelen] = '\0'; } return 0; } /* ARGSUSED */ static int ip6_sa2str(const struct sockaddr_in6 *sa6, char *buf, size_t bufsiz, int flags) { unsigned int ifindex; const struct in6_addr *a6; int n; ifindex = (unsigned int)sa6->sin6_scope_id; a6 = &sa6->sin6_addr; #ifdef NI_NUMERICSCOPE if ((flags & NI_NUMERICSCOPE) != 0) { n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id); if (n < 0 || n >= bufsiz) return -1; else return n; } #endif /* if_indextoname() does not take buffer size. not a good api... */ if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) || IN6_IS_ADDR_MC_NODELOCAL(a6)) && bufsiz >= IF_NAMESIZE) { char *p = if_indextoname(ifindex, buf); if (p) { return(strlen(p)); } } /* last resort */ n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id); if (n < 0 || (size_t)n >= bufsiz) return -1; else return n; } #endif /* INET6 */ /* * getnameinfo_link(): * Format a link-layer address into a printable format, paying attention to * the interface type. */ /* ARGSUSED */ static int getnameinfo_link(const struct afd *afd, const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) { const struct sockaddr_dl *sdl = (const struct sockaddr_dl *)(const void *)sa; const struct fw_hwaddr *iha; int n; if (serv != NULL && servlen > 0) *serv = '\0'; if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 && sdl->sdl_slen == 0) { n = snprintf(host, hostlen, "link#%d", sdl->sdl_index); if (n >= hostlen) { *host = '\0'; return (EAI_MEMORY); } return (0); } if (sdl->sdl_nlen > 0 && sdl->sdl_alen == 0) { n = sdl->sdl_nlen; if (n >= hostlen) { *host = '\0'; return (EAI_MEMORY); } memcpy(host, sdl->sdl_data, sdl->sdl_nlen); host[n] = '\0'; return (0); } switch (sdl->sdl_type) { case IFT_IEEE1394: if (sdl->sdl_alen < sizeof(iha->sender_unique_ID_hi) + sizeof(iha->sender_unique_ID_lo)) return EAI_FAMILY; iha = (const struct fw_hwaddr *)(const void *)LLADDR(sdl); return hexname((const u_int8_t *)&iha->sender_unique_ID_hi, sizeof(iha->sender_unique_ID_hi) + sizeof(iha->sender_unique_ID_lo), host, hostlen); /* * The following have zero-length addresses. * IFT_ATM (net/if_atmsubr.c) * IFT_GIF (net/if_gif.c) * IFT_LOOP (net/if_loop.c) * IFT_PPP (net/if_ppp.c, net/if_spppsubr.c) * IFT_SLIP (net/if_sl.c, net/if_strip.c) * IFT_STF (net/if_stf.c) * IFT_L2VLAN (net/if_vlan.c) * IFT_BRIDGE (net/if_bridge.h> */ /* * The following use IPv4 addresses as link-layer addresses: * IFT_OTHER (net/if_gre.c) * IFT_OTHER (netinet/ip_ipip.c) */ /* default below is believed correct for all these. */ case IFT_ARCNET: case IFT_ETHER: case IFT_FDDI: case IFT_HIPPI: case IFT_ISO88025: default: return hexname((u_int8_t *)LLADDR(sdl), (size_t)sdl->sdl_alen, host, hostlen); } } static int hexname(const u_int8_t *cp, size_t len, char *host, size_t hostlen) { int i, n; char *outp = host; *outp = '\0'; for (i = 0; i < len; i++) { n = snprintf(outp, hostlen, "%s%02x", i ? ":" : "", cp[i]); if (n < 0 || n >= hostlen) { *host = '\0'; return EAI_MEMORY; } outp += n; hostlen -= n; } return 0; } /* * getnameinfo_un(): * Format a UNIX IPC domain address (pathname). */ /* ARGSUSED */ static int getnameinfo_un(const struct afd *afd, const struct sockaddr *sa, socklen_t salen, char *host, size_t hostlen, char *serv, size_t servlen, int flags) { size_t pathlen; if (serv != NULL && servlen > 0) *serv = '\0'; if (host != NULL && hostlen > 0) { pathlen = sa->sa_len - afd->a_off; if (pathlen + 1 > hostlen) { *host = '\0'; return (EAI_MEMORY); } strlcpy(host, (const char *)sa + afd->a_off, pathlen + 1); } return (0); }