1 /*        $NetBSD: h_hostent.c,v 1.2 2014/01/09 02:18:10 christos Exp $         */
2 
3 /*-
4  * Copyright (c) 2013 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: h_hostent.c,v 1.2 2014/01/09 02:18:10 christos Exp $");
33 
34 #include <stdio.h>
35 #include <string.h>
36 #include <nsswitch.h>
37 #include <netdb.h>
38 #include <stdint.h>
39 #include <stdlib.h>
40 #include <unistd.h>
41 #include <err.h>
42 
43 #include <netinet/in.h>
44 #include <sys/types.h>
45 #include <arpa/nameser.h>
46 #include <arpa/inet.h>
47 
48 #include "hostent.h"
49 
50 extern const char *__res_conf_name;
51 
52 static void
phostent(const struct hostent * h)53 phostent(const struct hostent *h)
54 {
55           size_t i;
56           char buf[1024];
57           const int af = h->h_length == NS_INADDRSZ ? AF_INET : AF_INET6;
58 
59           printf("name=%s, length=%d, addrtype=%d, aliases=[",
60               h->h_name, h->h_length, h->h_addrtype);
61 
62           for (i = 0; h->h_aliases[i]; i++)
63                     printf("%s%s", i == 0 ? "" : " ", h->h_aliases[i]);
64 
65           printf("] addr_list=[");
66 
67           for (i = 0; h->h_addr_list[i]; i++)
68                     printf("%s%s", i == 0 ? "" : " ", inet_ntop(af,
69                         h->h_addr_list[i], buf, (socklen_t)sizeof(buf)));
70 
71           printf("]\n");
72 }
73 
74 static void
usage(void)75 usage(void)
76 {
77           (void)fprintf(stderr, "Usage: %s [-f <hostsfile>] "
78               "[-t <any|dns|nis|files>] "
79               "[-46a] <name|address>\n", getprogname());
80           exit(EXIT_FAILURE);
81 }
82 
83 static void
getby(int (* f)(void *,void *,va_list),struct getnamaddr * info,...)84 getby(int (*f)(void *, void *, va_list), struct getnamaddr *info, ...)
85 {
86           va_list ap;
87           int e;
88 
89           va_start(ap, info);
90           e = (*f)(info, NULL, ap);
91           va_end(ap);
92           switch (e) {
93           case NS_SUCCESS:
94                     phostent(info->hp);
95                     break;
96           default:
97                     printf("error %d\n", e);
98                     break;
99           }
100 }
101 
102 static void
geta(struct hostent * hp)103 geta(struct hostent *hp) {
104           if (hp == NULL)
105                     printf("error %d\n", h_errno);
106           else
107                     phostent(hp);
108 }
109 
110 int
main(int argc,char * argv[])111 main(int argc, char *argv[])
112 {
113           int (*f)(void *, void *, va_list) = NULL;
114           const char *type = "any";
115           int c, af, e, byaddr, len;
116           struct hostent hent;
117           struct getnamaddr info;
118           char buf[4096];
119 
120           af = AF_INET;
121           byaddr = 0;
122           len = 0;
123           info.hp = &hent;
124           info.buf = buf;
125           info.buflen = sizeof(buf);
126           info.he = &e;
127 
128           while ((c = getopt(argc, argv, "46af:r:t:")) != -1) {
129                     switch (c) {
130                     case '4':
131                               af = AF_INET;
132                               break;
133                     case '6':
134                               af = AF_INET6;
135                               break;
136                     case 'a':
137                               byaddr++;
138                               break;
139                     case 'f':
140                               _hf_sethostsfile(optarg);
141                               break;
142                     case 'r':
143                               __res_conf_name = optarg;
144                               break;
145                     case 't':
146                               type = optarg;
147                               break;
148                     default:
149                               usage();
150                     }
151           }
152 
153           argc -= optind;
154           argv += optind;
155 
156           if (argc != 1)
157                     usage();
158 
159           switch (*type) {
160           case 'a':
161                     break;
162           case 'd':
163                     f = byaddr ? _dns_gethtbyaddr : _dns_gethtbyname;
164                     break;
165 #ifdef YP
166           case 'n':
167                     f = byaddr ? _yp_gethtbyaddr : _yp_gethtbyname;
168                     break;
169 #endif
170           case 'f':
171                     f = byaddr ? _hf_gethtbyaddr : _hf_gethtbyname;
172                     break;
173           default:
174                     errx(EXIT_FAILURE, "Unknown db type `%s'", type);
175           }
176 
177           if (byaddr) {
178                     struct in6_addr addr;
179                     af = strchr(*argv, ':') ? AF_INET6 : AF_INET;
180                     len = af == AF_INET ? NS_INADDRSZ : NS_IN6ADDRSZ;
181                     if (inet_pton(af, *argv, &addr) == -1)
182                               err(EXIT_FAILURE, "Can't parse `%s'", *argv);
183                     if (*type == 'a')
184                               geta(gethostbyaddr((const char *)&addr, len, af));
185                     else
186                               getby(f, &info, &addr, len, af);
187           } else {
188                     if (*type == 'a')
189                               geta(gethostbyname2(*argv, af));
190                     else
191                               getby(f, &info, *argv, len, af);
192           }
193 
194           return 0;
195 }
196