fake-rfc2553.c revision 323134
1/*
2 * Copyright (C) 2000-2003 Damien Miller.  All rights reserved.
3 * Copyright (C) 1999 WIDE Project.  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 * 3. Neither the name of the project nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30/*
31 * Pseudo-implementation of RFC2553 name / address resolution functions
32 *
33 * But these functions are not implemented correctly. The minimum subset
34 * is implemented for ssh use only. For example, this routine assumes
35 * that ai_family is AF_INET. Don't use it for another purpose.
36 */
37
38#include "includes.h"
39
40#include <stdlib.h>
41#include <string.h>
42
43#include <netinet/in.h>
44#include <arpa/inet.h>
45
46#ifndef HAVE_GETNAMEINFO
47int getnameinfo(const struct sockaddr *sa, size_t salen, char *host,
48		size_t hostlen, char *serv, size_t servlen, int flags)
49{
50	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
51	struct hostent *hp;
52	char tmpserv[16];
53
54	if (sa->sa_family != AF_UNSPEC && sa->sa_family != AF_INET)
55		return (EAI_FAMILY);
56	if (serv != NULL) {
57		snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
58		if (strlcpy(serv, tmpserv, servlen) >= servlen)
59			return (EAI_MEMORY);
60	}
61
62	if (host != NULL) {
63		if (flags & NI_NUMERICHOST) {
64			if (strlcpy(host, inet_ntoa(sin->sin_addr),
65			    hostlen) >= hostlen)
66				return (EAI_MEMORY);
67			else
68				return (0);
69		} else {
70			hp = gethostbyaddr((char *)&sin->sin_addr,
71			    sizeof(struct in_addr), AF_INET);
72			if (hp == NULL)
73				return (EAI_NODATA);
74
75			if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
76				return (EAI_MEMORY);
77			else
78				return (0);
79		}
80	}
81	return (0);
82}
83#endif /* !HAVE_GETNAMEINFO */
84
85#ifndef HAVE_GAI_STRERROR
86#ifdef HAVE_CONST_GAI_STRERROR_PROTO
87const char *
88#else
89char *
90#endif
91gai_strerror(int err)
92{
93	switch (err) {
94	case EAI_NODATA:
95		return ("no address associated with name");
96	case EAI_MEMORY:
97		return ("memory allocation failure.");
98	case EAI_NONAME:
99		return ("nodename nor servname provided, or not known");
100	case EAI_FAMILY:
101		return ("ai_family not supported");
102	default:
103		return ("unknown/invalid error.");
104	}
105}
106#endif /* !HAVE_GAI_STRERROR */
107
108#ifndef HAVE_FREEADDRINFO
109void
110freeaddrinfo(struct addrinfo *ai)
111{
112	struct addrinfo *next;
113
114	for(; ai != NULL;) {
115		next = ai->ai_next;
116		free(ai);
117		ai = next;
118	}
119}
120#endif /* !HAVE_FREEADDRINFO */
121
122#ifndef HAVE_GETADDRINFO
123static struct
124addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
125{
126	struct addrinfo *ai;
127
128	ai = malloc(sizeof(*ai) + sizeof(struct sockaddr_in));
129	if (ai == NULL)
130		return (NULL);
131
132	memset(ai, '\0', sizeof(*ai) + sizeof(struct sockaddr_in));
133
134	ai->ai_addr = (struct sockaddr *)(ai + 1);
135	/* XXX -- ssh doesn't use sa_len */
136	ai->ai_addrlen = sizeof(struct sockaddr_in);
137	ai->ai_addr->sa_family = ai->ai_family = AF_INET;
138
139	((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
140	((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
141
142	/* XXX: the following is not generally correct, but does what we want */
143	if (hints->ai_socktype)
144		ai->ai_socktype = hints->ai_socktype;
145	else
146		ai->ai_socktype = SOCK_STREAM;
147
148	if (hints->ai_protocol)
149		ai->ai_protocol = hints->ai_protocol;
150
151	return (ai);
152}
153
154int
155getaddrinfo(const char *hostname, const char *servname,
156    const struct addrinfo *hints, struct addrinfo **res)
157{
158	struct hostent *hp;
159	struct servent *sp;
160	struct in_addr in;
161	int i;
162	long int port;
163	u_long addr;
164
165	port = 0;
166	if (hints && hints->ai_family != AF_UNSPEC &&
167	    hints->ai_family != AF_INET)
168		return (EAI_FAMILY);
169	if (servname != NULL) {
170		char *cp;
171
172		port = strtol(servname, &cp, 10);
173		if (port > 0 && port <= 65535 && *cp == '\0')
174			port = htons(port);
175		else if ((sp = getservbyname(servname, NULL)) != NULL)
176			port = sp->s_port;
177		else
178			port = 0;
179	}
180
181	if (hints && hints->ai_flags & AI_PASSIVE) {
182		addr = htonl(0x00000000);
183		if (hostname && inet_aton(hostname, &in) != 0)
184			addr = in.s_addr;
185		*res = malloc_ai(port, addr, hints);
186		if (*res == NULL)
187			return (EAI_MEMORY);
188		return (0);
189	}
190
191	if (!hostname) {
192		*res = malloc_ai(port, htonl(0x7f000001), hints);
193		if (*res == NULL)
194			return (EAI_MEMORY);
195		return (0);
196	}
197
198	if (inet_aton(hostname, &in)) {
199		*res = malloc_ai(port, in.s_addr, hints);
200		if (*res == NULL)
201			return (EAI_MEMORY);
202		return (0);
203	}
204
205	/* Don't try DNS if AI_NUMERICHOST is set */
206	if (hints && hints->ai_flags & AI_NUMERICHOST)
207		return (EAI_NONAME);
208
209	hp = gethostbyname(hostname);
210	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
211		struct addrinfo *cur, *prev;
212
213		cur = prev = *res = NULL;
214		for (i = 0; hp->h_addr_list[i]; i++) {
215			struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
216
217			cur = malloc_ai(port, in->s_addr, hints);
218			if (cur == NULL) {
219				if (*res != NULL)
220					freeaddrinfo(*res);
221				return (EAI_MEMORY);
222			}
223			if (prev)
224				prev->ai_next = cur;
225			else
226				*res = cur;
227
228			prev = cur;
229		}
230		return (0);
231	}
232
233	return (EAI_NODATA);
234}
235#endif /* !HAVE_GETADDRINFO */
236