Remove some unnecessary casts.
[dragonfly.git] / lib / libutil / realhostname.c
CommitLineData
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1/*-
2 * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: src/lib/libutil/realhostname.c,v 1.6.2.6 2002/06/29 18:26:37 ume Exp $
1de703da 27 * $DragonFly: src/lib/libutil/realhostname.c,v 1.2 2003/06/17 04:26:52 dillon Exp $
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28 */
29
30#include <sys/param.h>
31
32#include <sys/socket.h>
33#include <netdb.h>
34#include <netinet/in.h>
35#include <arpa/inet.h>
36
37#include <stdio.h>
38#include <string.h>
39
40#include "libutil.h"
41
42/* wrapper for KAME-special getnameinfo() */
43#ifndef NI_WITHSCOPEID
44#define NI_WITHSCOPEID 0
45#endif
46
47struct sockinet {
48 u_char si_len;
49 u_char si_family;
50 u_short si_port;
51};
52
53int
54realhostname(char *host, size_t hsize, const struct in_addr *ip)
55{
56 char trimmed[MAXHOSTNAMELEN];
57 int result;
58 struct hostent *hp;
59
60 result = HOSTNAME_INVALIDADDR;
15b85273 61 hp = gethostbyaddr(ip, sizeof(*ip), AF_INET);
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62
63 if (hp != NULL) {
64 strlcpy(trimmed, hp->h_name, sizeof(trimmed));
65 trimdomain(trimmed, strlen(trimmed));
66 if (strlen(trimmed) <= hsize) {
67 char lookup[MAXHOSTNAMELEN];
68
69 strncpy(lookup, hp->h_name, sizeof(lookup) - 1);
70 lookup[sizeof(lookup) - 1] = '\0';
71 hp = gethostbyname(lookup);
72 if (hp == NULL)
73 result = HOSTNAME_INVALIDNAME;
74 else for (; ; hp->h_addr_list++) {
75 if (*hp->h_addr_list == NULL) {
76 result = HOSTNAME_INCORRECTNAME;
77 break;
78 }
79 if (!memcmp(*hp->h_addr_list, ip, sizeof(*ip))) {
80 strncpy(host, trimmed, hsize);
81 return HOSTNAME_FOUND;
82 }
83 }
84 }
85 }
86
87 strncpy(host, inet_ntoa(*ip), hsize);
88
89 return result;
90}
91
92int
93realhostname_sa(char *host, size_t hsize, struct sockaddr *addr, int addrlen)
94{
95 int result, error;
96 char buf[NI_MAXHOST];
97 struct sockaddr_in sin;
98
99 result = HOSTNAME_INVALIDADDR;
100
101#ifdef INET6
102 /* IPv4 mapped IPv6 addr consideraton, specified in rfc2373. */
103 if (addr->sa_family == AF_INET6 &&
104 addrlen == sizeof(struct sockaddr_in6) &&
105 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)addr)->sin6_addr)) {
106 struct sockaddr_in6 *sin6;
107
108 sin6 = (struct sockaddr_in6 *)addr;
109
110 memset(&sin, 0, sizeof(sin));
111 sin.sin_len = sizeof(struct sockaddr_in);
112 sin.sin_family = AF_INET;
113 sin.sin_port = sin6->sin6_port;
114 memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
115 sizeof(struct in_addr));
116 addr = (struct sockaddr *)&sin;
117 addrlen = sin.sin_len;
118 }
119#endif
120
121 error = getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0,
122 NI_WITHSCOPEID | NI_NAMEREQD);
123 if (error == 0) {
124 struct addrinfo hints, *res, *ores;
125 struct sockaddr *sa;
126
127 memset(&hints, 0, sizeof(struct addrinfo));
128 hints.ai_family = addr->sa_family;
129 hints.ai_flags = AI_CANONNAME | AI_PASSIVE;
130 hints.ai_socktype = SOCK_STREAM;
131
132 error = getaddrinfo(buf, NULL, &hints, &res);
133 if (error) {
134 result = HOSTNAME_INVALIDNAME;
135 goto numeric;
136 }
137 for (ores = res; ; res = res->ai_next) {
138 if (res == NULL) {
139 freeaddrinfo(ores);
140 result = HOSTNAME_INCORRECTNAME;
141 goto numeric;
142 }
143 sa = res->ai_addr;
144 if (sa == NULL) {
145 freeaddrinfo(ores);
146 result = HOSTNAME_INCORRECTNAME;
147 goto numeric;
148 }
149 if (sa->sa_len == addrlen &&
150 sa->sa_family == addr->sa_family) {
151 ((struct sockinet *)sa)->si_port = ((struct sockinet *)addr)->si_port;
152#ifdef INET6
153 /*
154 * XXX: sin6_socpe_id may not been
155 * filled by DNS
156 */
157 if (sa->sa_family == AF_INET6 &&
158 ((struct sockaddr_in6 *)sa)->sin6_scope_id == 0)
159 ((struct sockaddr_in6 *)sa)->sin6_scope_id = ((struct sockaddr_in6 *)addr)->sin6_scope_id;
160#endif
161 if (!memcmp(sa, addr, sa->sa_len)) {
162 result = HOSTNAME_FOUND;
163 if (ores->ai_canonname == NULL) {
164 freeaddrinfo(ores);
165 goto numeric;
166 }
167 strlcpy(buf, ores->ai_canonname,
168 sizeof(buf));
169 trimdomain(buf, hsize);
170 if (strlen(buf) > hsize &&
171 addr->sa_family == AF_INET) {
172 freeaddrinfo(ores);
173 goto numeric;
174 }
175 strncpy(host, buf, hsize);
176 break;
177 }
178 }
179 }
180 freeaddrinfo(ores);
181 } else {
182 numeric:
183 if (getnameinfo(addr, addrlen, buf, sizeof(buf), NULL, 0,
184 NI_NUMERICHOST|NI_WITHSCOPEID) == 0)
185 strncpy(host, buf, hsize);
186 }
187
188 return result;
189}
190
191