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/*-
* Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <string.h>
#include "libutil.h"
/* wrapper for KAME-special getnameinfo() */
#ifndef NI_WITHSCOPEID
#define NI_WITHSCOPEID 0
#endif
struct sockinet {
u_char si_len;
u_char si_family;
u_short si_port;
};
int
realhostname(char *host, size_t hsize, const struct in_addr *ip)
{
int result;
struct hostent *hp;
result = HOSTNAME_INVALIDADDR;
hp = gethostbyaddr((char *)ip, sizeof(*ip), AF_INET);
if (hp != NULL && strlen(hp->h_name) <= hsize) {
char lookup[MAXHOSTNAMELEN];
strncpy(lookup, hp->h_name, sizeof(lookup) - 1);
lookup[sizeof(lookup) - 1] = '\0';
hp = gethostbyname(lookup);
if (hp == NULL)
result = HOSTNAME_INVALIDNAME;
else for (; ; hp->h_addr_list++) {
if (hp->h_addr_list[0] == NULL) {
result = HOSTNAME_INCORRECTNAME;
break;
}
if (!memcmp(*hp->h_addr_list, ip, sizeof(*ip))) {
strncpy(host, lookup, hsize);
return HOSTNAME_FOUND;
}
}
}
strncpy(host, inet_ntoa(*ip), hsize);
return result;
}
int
realhostname_sa(char *host, size_t hsize, struct sockaddr *addr, int addrlen)
{
int result, error;
char buf[NI_MAXHOST];
result = HOSTNAME_INVALIDADDR;
error = getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0, 0);
if (error == 0) {
struct addrinfo hints, *res, *ores;
struct sockaddr *sa;
memset(&hints, 0, sizeof(struct addrinfo));
hints.ai_family =
(addr->sa_family == AF_INET) ? AF_INET : AF_UNSPEC;
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo(buf, NULL, &hints, &res);
if (error) {
result = HOSTNAME_INVALIDNAME;
goto numeric;
} else for (ores = res; ; res = res->ai_next) {
if (res == NULL) {
freeaddrinfo(ores);
result = HOSTNAME_INCORRECTNAME;
goto numeric;
}
sa = res->ai_addr;
if (sa == NULL) {
freeaddrinfo(ores);
result = HOSTNAME_INCORRECTNAME;
goto numeric;
}
if (sa->sa_len == addrlen &&
sa->sa_family == addr->sa_family) {
u_int16_t port;
port = ((struct sockinet *)addr)->si_port;
((struct sockinet *)addr)->si_port = 0;
if (!memcmp(sa, addr, sa->sa_len)) {
result = HOSTNAME_FOUND;
((struct sockinet *)addr)->si_port =
port;
if (ores->ai_canonname == 0) {
freeaddrinfo(ores);
goto numeric;
}
if (strlen(ores->ai_canonname) > hsize) {
if (addr->sa_family == AF_INET) {
freeaddrinfo(ores);
goto numeric;
}
strncpy(buf,
ores->ai_canonname,
sizeof(buf));
trimdomain(buf, hsize);
strncpy(host, buf, hsize);
} else
strncpy(host,
ores->ai_canonname,
hsize);
break;
}
((struct sockinet *)addr)->si_port = port;
}
#ifdef INET6
/*
* XXX IPv4 mapped IPv6 addr consideraton,
* specified in rfc2373.
*/
if (sa->sa_family == AF_INET &&
addr->sa_family == AF_INET6) {
struct in_addr *in;
struct in6_addr *in6;
in = &((struct sockaddr_in *)sa)->sin_addr;
in6 = &((struct sockaddr_in6 *)addr)->sin6_addr;
if (IN6_IS_ADDR_V4MAPPED(in6) &&
!memcmp(&in6->s6_addr[12], in,
sizeof(*in))) {
result = HOSTNAME_FOUND;
if (ores->ai_canonname == 0 ||
strlen(ores->ai_canonname) > hsize) {
freeaddrinfo(ores);
goto numeric;
}
strncpy(host, ores->ai_canonname,
hsize);
break;
}
}
#endif
}
freeaddrinfo(ores);
} else {
struct sockaddr_in sin;
numeric:
#ifdef INET6
if (addr->sa_family == AF_INET6) {
struct sockaddr_in6 *sin6;
sin6 = (struct sockaddr_in6 *)addr;
if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
memset(&sin, 0, sizeof(sin));
sin.sin_len = sizeof(struct sockaddr_in);
sin.sin_family = AF_INET;
sin.sin_port = sin6->sin6_port;
memcpy(&sin.sin_addr,
&sin6->sin6_addr.s6_addr[12],
sizeof(struct in_addr));
addr = (struct sockaddr *)&sin;
addrlen = sin.sin_len;
}
}
#endif
if (getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0,
NI_NUMERICHOST|NI_WITHSCOPEID) == 0)
strncpy(host, buf, hsize);
}
return result;
}
|
