getnameinfo.c revision 75115
155682Smarkm/* 255682Smarkm * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 355682Smarkm * All rights reserved. 455682Smarkm * 555682Smarkm * Redistribution and use in source and binary forms, with or without 655682Smarkm * modification, are permitted provided that the following conditions 755682Smarkm * are met: 855682Smarkm * 1. Redistributions of source code must retain the above copyright 955682Smarkm * notice, this list of conditions and the following disclaimer. 1055682Smarkm * 2. Redistributions in binary form must reproduce the above copyright 1155682Smarkm * notice, this list of conditions and the following disclaimer in the 1255682Smarkm * documentation and/or other materials provided with the distribution. 1355682Smarkm * 3. Neither the name of the project nor the names of its contributors 1455682Smarkm * may be used to endorse or promote products derived from this software 1555682Smarkm * without specific prior written permission. 1655682Smarkm * 1755682Smarkm * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 1855682Smarkm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1955682Smarkm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2055682Smarkm * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 2155682Smarkm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2255682Smarkm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2355682Smarkm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2455682Smarkm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2555682Smarkm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2655682Smarkm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2755682Smarkm * SUCH DAMAGE. 2855682Smarkm */ 2955682Smarkm 3055682Smarkm/* 3155682Smarkm * Issues to be discussed: 3255682Smarkm * - Thread safe-ness must be checked 3355682Smarkm * - Return values. There seems to be no standard for return value (RFC2553) 3455682Smarkm * but INRIA implementation returns EAI_xxx defined for getaddrinfo(). 3555682Smarkm * - RFC2553 says that we should raise error on short buffer. X/Open says 3655682Smarkm * we need to truncate the result. We obey RFC2553 (and X/Open should be 3755682Smarkm * modified). 3855682Smarkm */ 39233294Sstas 4055682Smarkm#ifdef HAVE_CONFIG_H 4155682Smarkm#include <config.h> 4255682Smarkm#endif 4355682Smarkm 4455682Smarkm#ifndef lint 4555682Smarkmstatic const char rcsid[] = 4655682Smarkm "@(#) $Header: /tcpdump/master/tcpdump/missing/getnameinfo.c,v 1.8 2000/10/24 00:56:53 fenner Exp $"; 4755682Smarkm#endif 4855682Smarkm 4955682Smarkm#include <sys/types.h> 5055682Smarkm#include <sys/socket.h> 5155682Smarkm#include <net/if.h> 5255682Smarkm#include <netinet/in.h> 5355682Smarkm#include <arpa/inet.h> 5455682Smarkm#include <arpa/nameser.h> 5555682Smarkm#include <netdb.h> 5655682Smarkm#include <resolv.h> 5755682Smarkm#include <string.h> 5855682Smarkm#include <stddef.h> 5955682Smarkm#include <errno.h> 6055682Smarkm 6155682Smarkm#ifdef NEED_ADDRINFO_H 6255682Smarkm#include "addrinfo.h" 6355682Smarkm#endif 6455682Smarkm 6555682Smarkm#define SUCCESS 0 6655682Smarkm#define ANY 0 6755682Smarkm#define YES 1 6855682Smarkm#define NO 0 6955682Smarkm 7055682Smarkmstatic struct afd { 7155682Smarkm int a_af; 7255682Smarkm int a_addrlen; 7355682Smarkm int a_socklen; 7455682Smarkm int a_off; 7555682Smarkm} afdl [] = { 7655682Smarkm#ifdef INET6 7755682Smarkm {PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6), 7855682Smarkm offsetof(struct sockaddr_in6, sin6_addr)}, 7955682Smarkm#endif 8055682Smarkm {PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in), 8155682Smarkm offsetof(struct sockaddr_in, sin_addr)}, 8255682Smarkm {0, 0, 0}, 8355682Smarkm}; 8478527Sassar 8555682Smarkmstruct sockinet { 8655682Smarkm u_char si_len; 8755682Smarkm u_char si_family; 8855682Smarkm u_short si_port; 8955682Smarkm}; 9055682Smarkm 9155682Smarkm#define ENI_NOSOCKET 0 9255682Smarkm#define ENI_NOSERVNAME 1 9355682Smarkm#define ENI_NOHOSTNAME 2 9455682Smarkm#define ENI_MEMORY 3 9555682Smarkm#define ENI_SYSTEM 4 9655682Smarkm#define ENI_FAMILY 5 9755682Smarkm#define ENI_SALEN 6 9855682Smarkm 9955682Smarkmint 10055682Smarkmgetnameinfo(sa, salen, host, hostlen, serv, servlen, flags) 10155682Smarkm const struct sockaddr *sa; 10255682Smarkm size_t salen; 10355682Smarkm char *host; 10455682Smarkm size_t hostlen; 10578527Sassar char *serv; 10678527Sassar size_t servlen; 10778527Sassar int flags; 10878527Sassar{ 10978527Sassar struct afd *afd; 11078527Sassar struct servent *sp; 11178527Sassar struct hostent *hp; 11278527Sassar u_short port; 11378527Sassar int family, i; 11478527Sassar char *addr, *p; 11578527Sassar u_int32_t v4a; 11678527Sassar int h_error; 11778527Sassar char numserv[512]; 11878527Sassar char numaddr[512]; 11978527Sassar 12078527Sassar if (sa == NULL) 12155682Smarkm return ENI_NOSOCKET; 12255682Smarkm 12355682Smarkm#ifdef HAVE_SA_LEN /*XXX*/ 12455682Smarkm if (sa->sa_len != salen) 12555682Smarkm return ENI_SALEN; 12655682Smarkm#endif 12755682Smarkm 12855682Smarkm family = sa->sa_family; 12955682Smarkm for (i = 0; afdl[i].a_af; i++) 13055682Smarkm if (afdl[i].a_af == family) { 13155682Smarkm afd = &afdl[i]; 13255682Smarkm goto found; 13355682Smarkm } 13455682Smarkm return ENI_FAMILY; 13555682Smarkm 13655682Smarkm found: 13755682Smarkm if (salen != afd->a_socklen) 13855682Smarkm return ENI_SALEN; 13955682Smarkm 14055682Smarkm port = ((struct sockinet *)sa)->si_port; /* network byte order */ 14155682Smarkm addr = (char *)sa + afd->a_off; 14255682Smarkm 14355682Smarkm if (serv == NULL || servlen == 0) { 14455682Smarkm /* 145178825Sdfr * do nothing in this case. 14655682Smarkm * in case you are wondering if "&&" is more correct than 14755682Smarkm * "||" here: RFC2553 says that serv == NULL OR servlen == 0 14855682Smarkm * means that the caller does not want the result. 14955682Smarkm */ 15055682Smarkm } else { 15155682Smarkm if (flags & NI_NUMERICSERV) 15255682Smarkm sp = NULL; 153178825Sdfr else { 154178825Sdfr sp = getservbyport(port, 155178825Sdfr (flags & NI_DGRAM) ? "udp" : "tcp"); 156178825Sdfr } 15755682Smarkm if (sp) { 158178825Sdfr if (strlen(sp->s_name) + 1 > servlen) 159178825Sdfr return ENI_MEMORY; 160178825Sdfr strcpy(serv, sp->s_name); 161178825Sdfr } else { 162178825Sdfr snprintf(numserv, sizeof(numserv), "%d", ntohs(port)); 163178825Sdfr if (strlen(numserv) + 1 > servlen) 164178825Sdfr return ENI_MEMORY; 165178825Sdfr strcpy(serv, numserv); 16655682Smarkm } 16755682Smarkm } 168178825Sdfr 169178825Sdfr switch (sa->sa_family) { 17055682Smarkm case AF_INET: 17155682Smarkm v4a = (u_int32_t) 17255682Smarkm ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr); 17355682Smarkm if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a)) 17455682Smarkm flags |= NI_NUMERICHOST; 17555682Smarkm v4a >>= IN_CLASSA_NSHIFT; 17655682Smarkm if (v4a == 0) 17755682Smarkm flags |= NI_NUMERICHOST; 17855682Smarkm break; 17955682Smarkm#ifdef INET6 18055682Smarkm case AF_INET6: 18155682Smarkm { 18255682Smarkm struct sockaddr_in6 *sin6; 18355682Smarkm sin6 = (struct sockaddr_in6 *)sa; 18455682Smarkm switch (sin6->sin6_addr.s6_addr[0]) { 18555682Smarkm case 0x00: 18655682Smarkm if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) 18755682Smarkm ; 18855682Smarkm else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr)) 18955682Smarkm ; 19055682Smarkm else 19155682Smarkm flags |= NI_NUMERICHOST; 192233294Sstas break; 19355682Smarkm default: 19455682Smarkm if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) { 19555682Smarkm flags |= NI_NUMERICHOST; 19655682Smarkm } 19755682Smarkm else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) 19855682Smarkm flags |= NI_NUMERICHOST; 19955682Smarkm break; 20055682Smarkm } 20155682Smarkm } 20255682Smarkm break; 20355682Smarkm#endif 20455682Smarkm } 20555682Smarkm if (host == NULL || hostlen == 0) { 20655682Smarkm /* 20755682Smarkm * do nothing in this case. 20855682Smarkm * in case you are wondering if "&&" is more correct than 20955682Smarkm * "||" here: RFC2553 says that host == NULL OR hostlen == 0 21055682Smarkm * means that the caller does not want the result. 21155682Smarkm */ 21255682Smarkm } else if (flags & NI_NUMERICHOST) { 21355682Smarkm /* NUMERICHOST and NAMEREQD conflicts with each other */ 21455682Smarkm if (flags & NI_NAMEREQD) 21555682Smarkm return ENI_NOHOSTNAME; 21655682Smarkm if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) 21755682Smarkm == NULL) 21855682Smarkm return ENI_SYSTEM; 21955682Smarkm if (strlen(numaddr) + 1 > hostlen) 22055682Smarkm return ENI_MEMORY; 22155682Smarkm strcpy(host, numaddr); 22255682Smarkm#if defined(INET6) && defined(NI_WITHSCOPEID) 22355682Smarkm if (afd->a_af == AF_INET6 && 22455682Smarkm (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) || 22555682Smarkm IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) && 22655682Smarkm ((struct sockaddr_in6 *)sa)->sin6_scope_id) { 22755682Smarkm#ifndef ALWAYS_WITHSCOPE 22855682Smarkm if (flags & NI_WITHSCOPEID) 22955682Smarkm#endif /* !ALWAYS_WITHSCOPE */ 23055682Smarkm { 23155682Smarkm char *ep = strchr(host, '\0'); 23255682Smarkm unsigned int ifindex = 23355682Smarkm ((struct sockaddr_in6 *)sa)->sin6_scope_id; 23455682Smarkm 23555682Smarkm *ep = SCOPE_DELIMITER; 23655682Smarkm if ((if_indextoname(ifindex, ep + 1)) == NULL) 23755682Smarkm /* XXX what should we do? */ 23855682Smarkm strncpy(ep + 1, "???", 3); 23955682Smarkm } 24055682Smarkm } 24155682Smarkm#endif /* INET6 */ 24255682Smarkm } else { 24355682Smarkm#ifdef USE_GETIPNODEBY 24455682Smarkm hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error); 24555682Smarkm#else 24655682Smarkm hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af); 24755682Smarkm#ifdef HAVE_H_ERRNO 24855682Smarkm h_error = h_errno; 24955682Smarkm#else 25055682Smarkm h_error = EINVAL; 25155682Smarkm#endif 25255682Smarkm#endif 25355682Smarkm 25455682Smarkm if (hp) { 25555682Smarkm if (flags & NI_NOFQDN) { 25655682Smarkm p = strchr(hp->h_name, '.'); 25755682Smarkm if (p) *p = '\0'; 25855682Smarkm } 25955682Smarkm if (strlen(hp->h_name) + 1 > hostlen) { 26055682Smarkm#ifdef USE_GETIPNODEBY 26155682Smarkm freehostent(hp); 26255682Smarkm#endif 26355682Smarkm return ENI_MEMORY; 26455682Smarkm } 26555682Smarkm strcpy(host, hp->h_name); 26655682Smarkm#ifdef USE_GETIPNODEBY 26755682Smarkm freehostent(hp); 26855682Smarkm#endif 26955682Smarkm } else { 27055682Smarkm if (flags & NI_NAMEREQD) 27155682Smarkm return ENI_NOHOSTNAME; 27255682Smarkm if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr)) 27355682Smarkm == NULL) 27455682Smarkm return ENI_NOHOSTNAME; 27555682Smarkm if (strlen(numaddr) + 1 > hostlen) 27655682Smarkm return ENI_MEMORY; 27755682Smarkm strcpy(host, numaddr); 27855682Smarkm } 27955682Smarkm } 28055682Smarkm return SUCCESS; 28155682Smarkm} 28255682Smarkm