xref: /netbsd-src/usr.bin/getaddrinfo/getaddrinfo.c (revision 679f6f2d1c7e897ba9d9b2b6b61d8227aedcea4c)
1 /*	$NetBSD: getaddrinfo.c,v 1.5 2024/01/10 01:48:16 riastradh 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 Taylor R. Campbell.
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 
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: getaddrinfo.c,v 1.5 2024/01/10 01:48:16 riastradh Exp $");
34 
35 #include <sys/types.h>
36 #include <sys/socket.h>
37 
38 #include <assert.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <limits.h>
42 #include <netdb.h>
43 #include <stdbool.h>
44 #include <stdint.h>
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <util.h>
50 
51 #include "tables.h"
52 
53 static void	usage(void) __dead;
54 static void	printaddrinfo(struct addrinfo *);
55 static bool	parse_af(const char *, int *);
56 static bool	parse_protocol(const char *, int *);
57 static bool	parse_socktype(const char *, int *);
58 static bool	parse_numeric_tabular(const char *, int *, const char *const *,
59 		    size_t);
60 
61 int
main(int argc,char ** argv)62 main(int argc, char **argv)
63 {
64 	static const struct addrinfo zero_addrinfo;
65 	struct addrinfo hints = zero_addrinfo;
66 	struct addrinfo *addrinfo;
67 	const char *hostname = NULL, *service = NULL;
68 	int ch;
69 	int error;
70 
71 	setprogname(argv[0]);
72 
73 	hints.ai_family = AF_UNSPEC;
74 	hints.ai_socktype = 0;
75 	hints.ai_protocol = 0;
76 	hints.ai_flags = 0;
77 
78 	while ((ch = getopt(argc, argv, "cf:nNp:Ps:t:")) != -1) {
79 		switch (ch) {
80 		case 'c':
81 			hints.ai_flags |= AI_CANONNAME;
82 			break;
83 		case 'f':
84 			if (!parse_af(optarg, &hints.ai_family)) {
85 				warnx("invalid address family: %s", optarg);
86 				usage();
87 			}
88 			break;
89 		case 'n':
90 			hints.ai_flags |= AI_NUMERICHOST;
91 			break;
92 		case 'N':
93 			hints.ai_flags |= AI_NUMERICSERV;
94 			break;
95 		case 's':
96 			service = optarg;
97 			break;
98 		case 'p':
99 			if (!parse_protocol(optarg, &hints.ai_protocol)) {
100 				warnx("invalid protocol: %s", optarg);
101 				usage();
102 			}
103 			break;
104 		case 'P':
105 			hints.ai_flags |= AI_PASSIVE;
106 			break;
107 		case 't':
108 			if (!parse_socktype(optarg, &hints.ai_socktype)) {
109 				warnx("invalid socket type: %s", optarg);
110 				usage();
111 			}
112 			break;
113 		case '?':
114 		default:
115 			usage();
116 		}
117 	}
118 
119 	argc -= optind;
120 	argv += optind;
121 
122 	if (!((argc == 1) || ((argc == 0) && (hints.ai_flags & AI_PASSIVE))))
123 		usage();
124 	if (argc == 1)
125 		hostname = argv[0];
126 
127 	if (service != NULL) {
128 		char *p;
129 
130 		if ((p = strchr(service, '/')) != NULL) {
131 			if (hints.ai_protocol != 0) {
132 				warnx("protocol already specified");
133 				usage();
134 			}
135 			*p = '\0';
136 			p++;
137 
138 			if (!parse_protocol(p, &hints.ai_protocol)) {
139 				warnx("invalid protocol: %s", p);
140 				usage();
141 			}
142 		}
143 	}
144 
145 	error = getaddrinfo(hostname, service, &hints, &addrinfo);
146 	if (error)
147 		errx(1, "%s", gai_strerror(error));
148 
149 	if ((hints.ai_flags & AI_CANONNAME) && (addrinfo != NULL)) {
150 		if (printf("canonname %s\n", addrinfo->ai_canonname) < 0)
151 			err(1, "printf");
152 	}
153 
154 	printaddrinfo(addrinfo);
155 
156 	freeaddrinfo(addrinfo);
157 
158 	return 0;
159 }
160 
161 static void __dead
usage(void)162 usage(void)
163 {
164 
165 	(void)fprintf(stderr, "Usage: %s", getprogname());
166 	(void)fprintf(stderr,
167 	    " [-f <family>] [-p <protocol>] [-t <socktype>] [-s <service>]\n");
168 	(void)fprintf(stderr, "   [-cnNP] [<hostname>]\n");
169 	exit(1);
170 }
171 
172 static bool
parse_af(const char * string,int * afp)173 parse_af(const char *string, int *afp)
174 {
175 
176 	return parse_numeric_tabular(string, afp, address_families,
177 	    __arraycount(address_families));
178 }
179 
180 static bool
parse_protocol(const char * string,int * protop)181 parse_protocol(const char *string, int *protop)
182 {
183 	struct protoent *protoent;
184 	char *end;
185 	long value;
186 
187 	errno = 0;
188 	value = strtol(string, &end, 0);
189 	if ((string[0] == '\0') || (*end != '\0'))
190 		goto numeric_failed;
191 	if ((errno == ERANGE) && ((value == LONG_MAX) || (value == LONG_MIN)))
192 		goto numeric_failed;
193 	if ((value > INT_MAX) || (value < INT_MIN))
194 		goto numeric_failed;
195 
196 	*protop = value;
197 	return true;
198 
199 numeric_failed:
200 	protoent = getprotobyname(string);
201 	if (protoent == NULL)
202 		goto protoent_failed;
203 
204 	*protop = protoent->p_proto;
205 	return true;
206 
207 protoent_failed:
208 	return false;
209 }
210 
211 static bool
parse_socktype(const char * string,int * typep)212 parse_socktype(const char *string, int *typep)
213 {
214 
215 	return parse_numeric_tabular(string, typep, socket_types,
216 	    __arraycount(socket_types));
217 }
218 
219 static bool
parse_numeric_tabular(const char * string,int * valuep,const char * const * table,size_t n)220 parse_numeric_tabular(const char *string, int *valuep,
221     const char *const *table, size_t n)
222 {
223 	char *end;
224 	long value;
225 	size_t i;
226 
227 	assert((uintmax_t)n <= (uintmax_t)INT_MAX);
228 
229 	errno = 0;
230 	value = strtol(string, &end, 0);
231 	if ((string[0] == '\0') || (*end != '\0'))
232 		goto numeric_failed;
233 	if ((errno == ERANGE) && ((value == LONG_MAX) || (value == LONG_MIN)))
234 		goto numeric_failed;
235 	if ((value > INT_MAX) || (value < INT_MIN))
236 		goto numeric_failed;
237 
238 	*valuep = value;
239 	return true;
240 
241 numeric_failed:
242 	for (i = 0; i < n; i++)
243 		if ((table[i] != NULL) && (strcmp(string, table[i]) == 0))
244 			break;
245 	if (i == n)
246 		goto table_failed;
247 	*valuep = i;
248 	return true;
249 
250 table_failed:
251 	return false;
252 }
253 
254 static void
printaddrinfo(struct addrinfo * addrinfo)255 printaddrinfo(struct addrinfo *addrinfo)
256 {
257 	struct addrinfo *ai;
258 	char buf[1024];
259 	int n;
260 	struct protoent *protoent;
261 
262 	for (ai = addrinfo; ai != NULL; ai = ai->ai_next) {
263 		/* Print the socket type.  */
264 		if ((ai->ai_socktype >= 0) &&
265 		    ((size_t)ai->ai_socktype < __arraycount(socket_types)) &&
266 		    (socket_types[ai->ai_socktype] != NULL))
267 			n = printf("%s", socket_types[ai->ai_socktype]);
268 		else
269 			n = printf("%d", ai->ai_socktype);
270 		if (n < 0)
271 			err(1, "printf");
272 
273 		/* Print the address family.  */
274 		if ((ai->ai_family >= 0) &&
275 		    ((size_t)ai->ai_family < __arraycount(address_families)) &&
276 		    (address_families[ai->ai_family] != NULL))
277 			n = printf(" %s", address_families[ai->ai_family]);
278 		else
279 			n = printf(" %d", ai->ai_family);
280 		if (n < 0)
281 			err(1, "printf");
282 
283 		/* Print the protocol number.  */
284 		protoent = getprotobynumber(ai->ai_protocol);
285 		if (protoent == NULL)
286 			n = printf(" %d", ai->ai_protocol);
287 		else
288 			n = printf(" %s", protoent->p_name);
289 		if (n < 0)
290 			err(1, "printf");
291 
292 		/* Format the sockaddr.  */
293 		switch (ai->ai_family) {
294 		case AF_INET:
295 		case AF_INET6:
296 			n = sockaddr_snprintf(buf, sizeof(buf), " %a %p",
297 			    ai->ai_addr);
298 			break;
299 		default:
300 			n = sockaddr_snprintf(buf, sizeof(buf),
301 			    "%a %p %I %F %R %S", ai->ai_addr);
302 		}
303 
304 		/*
305 		 * Check for sockaddr_snprintf failure.
306 		 *
307 		 * XXX sockaddr_snprintf's error reporting is botched
308 		 * -- man page says it sets errno, but if getnameinfo
309 		 * fails, errno is not where it reports the error...
310 		 */
311 		if (n < 0) {
312 			warnx("sockaddr_snprintf failed");
313 			continue;
314 		}
315 		if (sizeof(buf) <= (size_t)n)
316 			warnx("truncated sockaddr_snprintf output");
317 
318 		/* Print the formatted sockaddr.  */
319 		if (printf("%s\n", buf) < 0)
320 			err(1, "printf");
321 	}
322 }
323