xref: /freebsd/crypto/heimdal/lib/roken/getaddrinfo.c (revision c697fb7f)
1 /*
2  * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <config.h>
35 
36 #include "roken.h"
37 
38 /*
39  * uses hints->ai_socktype and hints->ai_protocol
40  */
41 
42 static int
43 get_port_protocol_socktype (const char *servname,
44 			    const struct addrinfo *hints,
45 			    int *port,
46 			    int *protocol,
47 			    int *socktype)
48 {
49     struct servent *se;
50     const char *proto_str = NULL;
51 
52     *socktype = 0;
53 
54     if (hints != NULL && hints->ai_protocol != 0) {
55 	struct protoent *protoent = getprotobynumber (hints->ai_protocol);
56 
57 	if (protoent == NULL)
58 	    return EAI_SOCKTYPE; /* XXX */
59 
60 	proto_str = protoent->p_name;
61 	*protocol = protoent->p_proto;
62     }
63 
64     if (hints != NULL)
65 	*socktype = hints->ai_socktype;
66 
67     if (*socktype == SOCK_STREAM) {
68 	se = getservbyname (servname, proto_str ? proto_str : "tcp");
69 	if (proto_str == NULL)
70 	    *protocol = IPPROTO_TCP;
71     } else if (*socktype == SOCK_DGRAM) {
72 	se = getservbyname (servname, proto_str ? proto_str : "udp");
73 	if (proto_str == NULL)
74 	    *protocol = IPPROTO_UDP;
75     } else if (*socktype == 0) {
76 	if (proto_str != NULL) {
77 	    se = getservbyname (servname, proto_str);
78 	} else {
79 	    se = getservbyname (servname, "tcp");
80 	    *protocol = IPPROTO_TCP;
81 	    *socktype = SOCK_STREAM;
82 	    if (se == NULL) {
83 		se = getservbyname (servname, "udp");
84 		*protocol = IPPROTO_UDP;
85 		*socktype = SOCK_DGRAM;
86 	    }
87 	}
88     } else
89 	return EAI_SOCKTYPE;
90 
91     if (se == NULL) {
92 	char *endstr;
93 
94 	*port = htons(strtol (servname, &endstr, 10));
95 	if (servname == endstr)
96 	    return EAI_NONAME;
97     } else {
98 	*port = se->s_port;
99     }
100     return 0;
101 }
102 
103 static int
104 add_one (int port, int protocol, int socktype,
105 	 struct addrinfo ***ptr,
106 	 int (*func)(struct addrinfo *, void *data, int port),
107 	 void *data,
108 	 char *canonname)
109 {
110     struct addrinfo *a;
111     int ret;
112 
113     a = malloc (sizeof (*a));
114     if (a == NULL)
115 	return EAI_MEMORY;
116     memset (a, 0, sizeof(*a));
117     a->ai_flags     = 0;
118     a->ai_next      = NULL;
119     a->ai_protocol  = protocol;
120     a->ai_socktype  = socktype;
121     a->ai_canonname = canonname;
122     ret = (*func)(a, data, port);
123     if (ret) {
124 	free (a);
125 	return ret;
126     }
127     **ptr = a;
128     *ptr = &a->ai_next;
129     return 0;
130 }
131 
132 static int
133 const_v4 (struct addrinfo *a, void *data, int port)
134 {
135     struct sockaddr_in *sin4;
136     struct in_addr *addr = (struct in_addr *)data;
137 
138     a->ai_family  = PF_INET;
139     a->ai_addrlen = sizeof(*sin4);
140     a->ai_addr    = malloc (sizeof(*sin4));
141     if (a->ai_addr == NULL)
142 	return EAI_MEMORY;
143     sin4 = (struct sockaddr_in *)a->ai_addr;
144     memset (sin4, 0, sizeof(*sin4));
145     sin4->sin_family = AF_INET;
146     sin4->sin_port   = port;
147     sin4->sin_addr   = *addr;
148     return 0;
149 }
150 
151 #ifdef HAVE_IPV6
152 static int
153 const_v6 (struct addrinfo *a, void *data, int port)
154 {
155     struct sockaddr_in6 *sin6;
156     struct in6_addr *addr = (struct in6_addr *)data;
157 
158     a->ai_family  = PF_INET6;
159     a->ai_addrlen = sizeof(*sin6);
160     a->ai_addr    = malloc (sizeof(*sin6));
161     if (a->ai_addr == NULL)
162 	return EAI_MEMORY;
163     sin6 = (struct sockaddr_in6 *)a->ai_addr;
164     memset (sin6, 0, sizeof(*sin6));
165     sin6->sin6_family = AF_INET6;
166     sin6->sin6_port   = port;
167     sin6->sin6_addr   = *addr;
168     return 0;
169 }
170 #endif
171 
172 /* this is mostly a hack for some versions of AIX that has a prototype
173    for in6addr_loopback but no actual symbol in libc */
174 #if defined(HAVE_IPV6) && !defined(HAVE_IN6ADDR_LOOPBACK) && defined(IN6ADDR_LOOPBACK_INIT)
175 #define in6addr_loopback _roken_in6addr_loopback
176 struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
177 #endif
178 
179 static int
180 get_null (const struct addrinfo *hints,
181 	  int port, int protocol, int socktype,
182 	  struct addrinfo **res)
183 {
184     struct in_addr v4_addr;
185 #ifdef HAVE_IPV6
186     struct in6_addr v6_addr;
187 #endif
188     struct addrinfo *first = NULL;
189     struct addrinfo **current = &first;
190     int family = PF_UNSPEC;
191     int ret;
192 
193     if (hints != NULL)
194 	family = hints->ai_family;
195 
196     if (hints && hints->ai_flags & AI_PASSIVE) {
197 	v4_addr.s_addr = INADDR_ANY;
198 #ifdef HAVE_IPV6
199 	v6_addr        = in6addr_any;
200 #endif
201     } else {
202 	v4_addr.s_addr = htonl(INADDR_LOOPBACK);
203 #ifdef HAVE_IPV6
204 	v6_addr        = in6addr_loopback;
205 #endif
206     }
207 
208 #ifdef HAVE_IPV6
209     if (family == PF_INET6 || family == PF_UNSPEC) {
210 	ret = add_one (port, protocol, socktype,
211 		       &current, const_v6, &v6_addr, NULL);
212     }
213 #endif
214     if (family == PF_INET || family == PF_UNSPEC) {
215 	ret = add_one (port, protocol, socktype,
216 		       &current, const_v4, &v4_addr, NULL);
217     }
218     *res = first;
219     return 0;
220 }
221 
222 static int
223 add_hostent (int port, int protocol, int socktype,
224 	     struct addrinfo ***current,
225 	     int (*func)(struct addrinfo *, void *data, int port),
226 	     struct hostent *he, int *flags)
227 {
228     int ret;
229     char *canonname = NULL;
230     char **h;
231 
232     if (*flags & AI_CANONNAME) {
233 	struct hostent *he2 = NULL;
234 	const char *tmp_canon;
235 
236 	tmp_canon = hostent_find_fqdn (he);
237 	if (strchr (tmp_canon, '.') == NULL) {
238 	    int error;
239 
240 	    he2 = getipnodebyaddr (he->h_addr_list[0], he->h_length,
241 				   he->h_addrtype, &error);
242 	    if (he2 != NULL) {
243 		const char *tmp = hostent_find_fqdn (he2);
244 
245 		if (strchr (tmp, '.') != NULL)
246 		    tmp_canon = tmp;
247 	    }
248 	}
249 
250 	canonname = strdup (tmp_canon);
251 	if (he2 != NULL)
252 	    freehostent (he2);
253 	if (canonname == NULL)
254 	    return EAI_MEMORY;
255     }
256 
257     for (h = he->h_addr_list; *h != NULL; ++h) {
258 	ret = add_one (port, protocol, socktype,
259 		       current, func, *h, canonname);
260 	if (ret)
261 	    return ret;
262 	if (*flags & AI_CANONNAME) {
263 	    *flags &= ~AI_CANONNAME;
264 	    canonname = NULL;
265 	}
266     }
267     return 0;
268 }
269 
270 static int
271 get_number (const char *nodename,
272 	    const struct addrinfo *hints,
273 	    int port, int protocol, int socktype,
274 	    struct addrinfo **res)
275 {
276     struct addrinfo *first = NULL;
277     struct addrinfo **current = &first;
278     int family = PF_UNSPEC;
279     int ret;
280 
281     if (hints != NULL) {
282 	family = hints->ai_family;
283     }
284 
285 #ifdef HAVE_IPV6
286     if (family == PF_INET6 || family == PF_UNSPEC) {
287 	struct in6_addr v6_addr;
288 
289 	if (inet_pton (PF_INET6, nodename, &v6_addr) == 1) {
290 	    ret = add_one (port, protocol, socktype,
291 			   &current, const_v6, &v6_addr, NULL);
292 	    *res = first;
293 	    return ret;
294 	}
295     }
296 #endif
297     if (family == PF_INET || family == PF_UNSPEC) {
298 	struct in_addr v4_addr;
299 
300 	if (inet_pton (PF_INET, nodename, &v4_addr) == 1) {
301 	    ret = add_one (port, protocol, socktype,
302 			   &current, const_v4, &v4_addr, NULL);
303 	    *res = first;
304 	    return ret;
305 	}
306     }
307     return EAI_NONAME;
308 }
309 
310 static int
311 get_nodes (const char *nodename,
312 	   const struct addrinfo *hints,
313 	   int port, int protocol, int socktype,
314 	   struct addrinfo **res)
315 {
316     struct addrinfo *first = NULL;
317     struct addrinfo **current = &first;
318     int family = PF_UNSPEC;
319     int flags  = 0;
320     int ret = EAI_NONAME;
321     int error;
322 
323     if (hints != NULL) {
324 	family = hints->ai_family;
325 	flags  = hints->ai_flags;
326     }
327 
328 #ifdef HAVE_IPV6
329     if (family == PF_INET6 || family == PF_UNSPEC) {
330 	struct hostent *he;
331 
332 	he = getipnodebyname (nodename, PF_INET6, 0, &error);
333 
334 	if (he != NULL) {
335 	    ret = add_hostent (port, protocol, socktype,
336 			       &current, const_v6, he, &flags);
337 	    freehostent (he);
338 	}
339     }
340 #endif
341     if (family == PF_INET || family == PF_UNSPEC) {
342 	struct hostent *he;
343 
344 	he = getipnodebyname (nodename, PF_INET, 0, &error);
345 
346 	if (he != NULL) {
347 	    ret = add_hostent (port, protocol, socktype,
348 			       &current, const_v4, he, &flags);
349 	    freehostent (he);
350 	}
351     }
352     *res = first;
353     return ret;
354 }
355 
356 /*
357  * hints:
358  *
359  * struct addrinfo {
360  *     int    ai_flags;
361  *     int    ai_family;
362  *     int    ai_socktype;
363  *     int    ai_protocol;
364  * ...
365  * };
366  */
367 
368 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
369 getaddrinfo(const char *nodename,
370 	    const char *servname,
371 	    const struct addrinfo *hints,
372 	    struct addrinfo **res)
373 {
374     int ret;
375     int port     = 0;
376     int protocol = 0;
377     int socktype = 0;
378 
379     *res = NULL;
380 
381     if (servname == NULL && nodename == NULL)
382 	return EAI_NONAME;
383 
384     if (hints != NULL
385 	&& hints->ai_family != PF_UNSPEC
386 	&& hints->ai_family != PF_INET
387 #ifdef HAVE_IPV6
388 	&& hints->ai_family != PF_INET6
389 #endif
390 	)
391 	return EAI_FAMILY;
392 
393     if (servname != NULL) {
394 	ret = get_port_protocol_socktype (servname, hints,
395 					  &port, &protocol, &socktype);
396 	if (ret)
397 	    return ret;
398     }
399     if (nodename != NULL) {
400 	ret = get_number (nodename, hints, port, protocol, socktype, res);
401 	if (ret) {
402 	    if(hints && hints->ai_flags & AI_NUMERICHOST)
403 		ret = EAI_NONAME;
404 	    else
405 		ret = get_nodes (nodename, hints, port, protocol, socktype,
406 				 res);
407 	}
408     } else {
409 	ret = get_null (hints, port, protocol, socktype, res);
410     }
411     if (ret)
412 	freeaddrinfo (*res);
413     return ret;
414 }
415