/* * 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 * - Return values.  There seems to be no standard for return value (RFC2553) *   but INRIA implementation returns EAI_xxx defined for getaddrinfo(). * - 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). */#ifdef HAVE_CONFIG_H#include <config.h>#endif#ifndef lintstatic const char rcsid[] _U_ =     "@(#) $Header: /tcpdump/master/tcpdump/missing/getnameinfo.c,v 1.11 2003/11/16 09:36:49 guy Exp $";#endif#include <sys/types.h>#include <sys/socket.h>#include <net/if.h>#include <netinet/in.h>#include <arpa/inet.h>#include <arpa/nameser.h>#include <netdb.h>#include <resolv.h>#include <string.h>#include <stddef.h>#include <errno.h>#ifdef NEED_ADDRINFO_H#include "addrinfo.h"#endif#define SUCCESS 0#define ANY 0#define YES 1#define NO  0static 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;};#define ENI_NOSOCKET 	0#define ENI_NOSERVNAME	1#define ENI_NOHOSTNAME	2#define ENI_MEMORY	3#define ENI_SYSTEM	4#define ENI_FAMILY	5#define ENI_SALEN	6intgetnameinfo(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;	int family, i;	char *addr, *p;	u_int32_t v4a;	int h_error;	char numserv[512];	char numaddr[512];	if (sa == NULL)		return ENI_NOSOCKET;#ifdef HAVE_SA_LEN	/*XXX*/	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;	port = ((struct sockinet *)sa)->si_port; /* network byte order */	addr = (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: 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(((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:	    {		struct sockaddr_in6 *sin6;		sin6 = (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: RFC2553 says that host == NULL OR hostlen == 0		 * means that the caller does not want the result.		 */	} else if (flags & NI_NUMERICHOST) {		/* NUMERICHOST and NAMEREQD conflicts with each other */		if (flags & NI_NAMEREQD)			return ENI_NOHOSTNAME;		if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))		    == NULL)			return ENI_SYSTEM;		if (strlen(numaddr) + 1 > hostlen)			return ENI_MEMORY;		strcpy(host, numaddr);#if defined(INET6) && defined(NI_WITHSCOPEID)		if (afd->a_af == AF_INET6 &&		    (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) ||		     IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) &&		    ((struct sockaddr_in6 *)sa)->sin6_scope_id) {#ifndef ALWAYS_WITHSCOPE			if (flags & NI_WITHSCOPEID)#endif /* !ALWAYS_WITHSCOPE */			{				char *ep = strchr(host, '\0');				unsigned int ifindex =					((struct sockaddr_in6 *)sa)->sin6_scope_id;				*ep = SCOPE_DELIMITER;				if ((if_indextoname(ifindex, ep + 1)) == NULL)					/* XXX what should we do? */					strncpy(ep + 1, "???", 3);			}		}#endif /* INET6 */	} else {#ifdef USE_GETIPNODEBY		hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);#else		hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);#ifdef HAVE_H_ERRNO		h_error = h_errno;#else		h_error = EINVAL;#endif#endif		if (hp) {			if (flags & NI_NOFQDN) {				p = strchr(hp->h_name, '.');				if (p) *p = '\0';			}			if (strlen(hp->h_name) + 1 > hostlen) {#ifdef USE_GETIPNODEBY				freehostent(hp);#endif				return ENI_MEMORY;			}			strcpy(host, hp->h_name);#ifdef USE_GETIPNODEBY			freehostent(hp);#endif		} else {			if (flags & NI_NAMEREQD)				return ENI_NOHOSTNAME;			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))			    == NULL)				return ENI_NOHOSTNAME;			if (strlen(numaddr) + 1 > hostlen)				return ENI_MEMORY;			strcpy(host, numaddr);		}	}	return SUCCESS;}