xref: /freebsd/crypto/openssh/openbsd-compat/fake-rfc2553.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
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 RCSID("$Id: fake-rfc2553.c,v 1.5 2003/09/22 02:08:23 dtucker Exp $");
41 
42 #ifndef HAVE_GETNAMEINFO
43 int getnameinfo(const struct sockaddr *sa, size_t salen, char *host,
44                 size_t hostlen, char *serv, size_t servlen, int flags)
45 {
46 	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
47 	struct hostent *hp;
48 	char tmpserv[16];
49 
50 	if (serv != NULL) {
51 		snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
52 		if (strlcpy(serv, tmpserv, servlen) >= servlen)
53 			return (EAI_MEMORY);
54 	}
55 
56 	if (host != NULL) {
57 		if (flags & NI_NUMERICHOST) {
58 			if (strlcpy(host, inet_ntoa(sin->sin_addr),
59 			    hostlen) >= hostlen)
60 				return (EAI_MEMORY);
61 			else
62 				return (0);
63 		} else {
64 			hp = gethostbyaddr((char *)&sin->sin_addr,
65 			    sizeof(struct in_addr), AF_INET);
66 			if (hp == NULL)
67 				return (EAI_NODATA);
68 
69 			if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
70 				return (EAI_MEMORY);
71 			else
72 				return (0);
73 		}
74 	}
75 	return (0);
76 }
77 #endif /* !HAVE_GETNAMEINFO */
78 
79 #ifndef HAVE_GAI_STRERROR
80 #ifdef HAVE_CONST_GAI_STRERROR_PROTO
81 const char *
82 #else
83 char *
84 #endif
85 gai_strerror(int err)
86 {
87 	switch (err) {
88 	case EAI_NODATA:
89 		return ("no address associated with name");
90 	case EAI_MEMORY:
91 		return ("memory allocation failure.");
92 	case EAI_NONAME:
93 		return ("nodename nor servname provided, or not known");
94 	default:
95 		return ("unknown/invalid error.");
96 	}
97 }
98 #endif /* !HAVE_GAI_STRERROR */
99 
100 #ifndef HAVE_FREEADDRINFO
101 void
102 freeaddrinfo(struct addrinfo *ai)
103 {
104 	struct addrinfo *next;
105 
106 	for(; ai != NULL;) {
107 		next = ai->ai_next;
108 		free(ai);
109 		ai = next;
110 	}
111 }
112 #endif /* !HAVE_FREEADDRINFO */
113 
114 #ifndef HAVE_GETADDRINFO
115 static struct
116 addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
117 {
118 	struct addrinfo *ai;
119 
120 	ai = malloc(sizeof(*ai) + sizeof(struct sockaddr_in));
121 	if (ai == NULL)
122 		return (NULL);
123 
124 	memset(ai, '\0', sizeof(*ai) + sizeof(struct sockaddr_in));
125 
126 	ai->ai_addr = (struct sockaddr *)(ai + 1);
127 	/* XXX -- ssh doesn't use sa_len */
128 	ai->ai_addrlen = sizeof(struct sockaddr_in);
129 	ai->ai_addr->sa_family = ai->ai_family = AF_INET;
130 
131 	((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
132 	((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
133 
134 	/* XXX: the following is not generally correct, but does what we want */
135 	if (hints->ai_socktype)
136 		ai->ai_socktype = hints->ai_socktype;
137 	else
138 		ai->ai_socktype = SOCK_STREAM;
139 
140 	if (hints->ai_protocol)
141 		ai->ai_protocol = hints->ai_protocol;
142 
143 	return (ai);
144 }
145 
146 int
147 getaddrinfo(const char *hostname, const char *servname,
148     const struct addrinfo *hints, struct addrinfo **res)
149 {
150 	struct hostent *hp;
151 	struct servent *sp;
152 	struct in_addr in;
153 	int i;
154 	long int port;
155 	u_long addr;
156 
157 	port = 0;
158 	if (servname != NULL) {
159 		char *cp;
160 
161 		port = strtol(servname, &cp, 10);
162 		if (port > 0 && port <= 65535 && *cp == '\0')
163 			port = htons(port);
164 		else if ((sp = getservbyname(servname, NULL)) != NULL)
165 			port = sp->s_port;
166 		else
167 			port = 0;
168 	}
169 
170 	if (hints && hints->ai_flags & AI_PASSIVE) {
171 		addr = htonl(0x00000000);
172 		if (hostname && inet_aton(hostname, &in) != 0)
173 			addr = in.s_addr;
174 		*res = malloc_ai(port, addr, hints);
175 		if (*res == NULL)
176 			return (EAI_MEMORY);
177 		return (0);
178 	}
179 
180 	if (!hostname) {
181 		*res = malloc_ai(port, htonl(0x7f000001), hints);
182 		if (*res == NULL)
183 			return (EAI_MEMORY);
184 		return (0);
185 	}
186 
187 	if (inet_aton(hostname, &in)) {
188 		*res = malloc_ai(port, in.s_addr, hints);
189 		if (*res == NULL)
190 			return (EAI_MEMORY);
191 		return (0);
192 	}
193 
194 	/* Don't try DNS if AI_NUMERICHOST is set */
195 	if (hints && hints->ai_flags & AI_NUMERICHOST)
196 		return (EAI_NONAME);
197 
198 	hp = gethostbyname(hostname);
199 	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
200 		struct addrinfo *cur, *prev;
201 
202 		cur = prev = *res = NULL;
203 		for (i = 0; hp->h_addr_list[i]; i++) {
204 			struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
205 
206 			cur = malloc_ai(port, in->s_addr, hints);
207 			if (cur == NULL) {
208 				if (*res != NULL)
209 					freeaddrinfo(*res);
210 				return (EAI_MEMORY);
211 			}
212 			if (prev)
213 				prev->ai_next = cur;
214 			else
215 				*res = cur;
216 
217 			prev = cur;
218 		}
219 		return (0);
220 	}
221 
222 	return (EAI_NODATA);
223 }
224 #endif /* !HAVE_GETADDRINFO */
225