xref: /freebsd/contrib/unbound/compat/fake-rfc2553.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /* From openssh 4.3p2 filename openbsd-compat/fake-rfc2553.h */
2 /*
3  * Copyright (C) 2000-2003 Damien Miller.  All rights reserved.
4  * Copyright (C) 1999 WIDE Project.  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  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the project nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 /*
32  * Pseudo-implementation of RFC2553 name / address resolution functions
33  *
34  * But these functions are not implemented correctly. The minimum subset
35  * is implemented for ssh use only. For example, this routine assumes
36  * that ai_family is AF_INET. Don't use it for another purpose.
37  */
38 
39 #include <unistd.h>
40 #include <string.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include "compat/fake-rfc2553.h"
44 
45 #ifndef HAVE_GETNAMEINFO
46 int getnameinfo(const struct sockaddr *sa, size_t ATTR_UNUSED(salen), char *host,
47                 size_t hostlen, char *serv, size_t servlen, int flags)
48 {
49 	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
50 	struct hostent *hp;
51 	char tmpserv[16];
52 
53 	if (serv != NULL) {
54 		snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
55 		if (strlcpy(serv, tmpserv, servlen) >= servlen)
56 			return (EAI_MEMORY);
57 	}
58 
59 	if (host != NULL) {
60 		if (flags & NI_NUMERICHOST) {
61 			if (strlcpy(host, inet_ntoa(sin->sin_addr),
62 			    hostlen) >= hostlen)
63 				return (EAI_MEMORY);
64 			else
65 				return (0);
66 		} else {
67 			hp = gethostbyaddr((char *)&sin->sin_addr,
68 			    sizeof(struct in_addr), AF_INET);
69 			if (hp == NULL)
70 				return (EAI_NODATA);
71 
72 			if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
73 				return (EAI_MEMORY);
74 			else
75 				return (0);
76 		}
77 	}
78 	return (0);
79 }
80 #endif /* !HAVE_GETNAMEINFO */
81 
82 #ifndef HAVE_GAI_STRERROR
83 #ifdef HAVE_CONST_GAI_STRERROR_PROTO
84 const char *
85 #else
86 char *
87 #endif
88 gai_strerror(int err)
89 {
90 	switch (err) {
91 	case EAI_NODATA:
92 		return ("no address associated with name");
93 	case EAI_MEMORY:
94 		return ("memory allocation failure.");
95 	case EAI_NONAME:
96 		return ("nodename nor servname provided, or not known");
97 	default:
98 		return ("unknown/invalid error.");
99 	}
100 }
101 #endif /* !HAVE_GAI_STRERROR */
102 
103 #ifndef HAVE_FREEADDRINFO
104 void
105 freeaddrinfo(struct addrinfo *ai)
106 {
107 	struct addrinfo *next;
108 
109 	for(; ai != NULL;) {
110 		next = ai->ai_next;
111 		free(ai);
112 		ai = next;
113 	}
114 }
115 #endif /* !HAVE_FREEADDRINFO */
116 
117 #ifndef HAVE_GETADDRINFO
118 static struct
119 addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
120 {
121 	struct addrinfo *ai;
122 
123 	ai = calloc(1, sizeof(*ai) + sizeof(struct sockaddr_in));
124 	if (ai == NULL)
125 		return (NULL);
126 
127 	ai->ai_addr = (struct sockaddr *)(ai + 1);
128 	/* XXX -- ssh doesn't use sa_len */
129 	ai->ai_addrlen = sizeof(struct sockaddr_in);
130 	ai->ai_addr->sa_family = ai->ai_family = AF_INET;
131 
132 	((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
133 	((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
134 
135 	/* XXX: the following is not generally correct, but does what we want */
136 	if (hints->ai_socktype)
137 		ai->ai_socktype = hints->ai_socktype;
138 	else
139 		ai->ai_socktype = SOCK_STREAM;
140 
141 	if (hints->ai_protocol)
142 		ai->ai_protocol = hints->ai_protocol;
143 
144 	return (ai);
145 }
146 
147 int
148 getaddrinfo(const char *hostname, const char *servname,
149     const struct addrinfo *hints, struct addrinfo **res)
150 {
151 	struct hostent *hp;
152 	struct servent *sp;
153 	struct in_addr in;
154 	int i;
155 	long int port;
156 	u_long addr;
157 
158 	port = 0;
159 	if (servname != NULL) {
160 		char *cp;
161 
162 		port = strtol(servname, &cp, 10);
163 		if (port > 0 && port <= 65535 && *cp == '\0')
164 			port = htons(port);
165 		else if ((sp = getservbyname(servname, NULL)) != NULL)
166 			port = sp->s_port;
167 		else
168 			port = 0;
169 	}
170 
171 	if (hints && hints->ai_flags & AI_PASSIVE) {
172 		addr = htonl(0x00000000);
173 		if (hostname && inet_aton(hostname, &in) != 0)
174 			addr = in.s_addr;
175 		*res = malloc_ai(port, addr, hints);
176 		if (*res == NULL)
177 			return (EAI_MEMORY);
178 		return (0);
179 	}
180 
181 	if (!hostname) {
182 		*res = malloc_ai(port, htonl(0x7f000001), hints);
183 		if (*res == NULL)
184 			return (EAI_MEMORY);
185 		return (0);
186 	}
187 
188 	if (inet_aton(hostname, &in)) {
189 		*res = malloc_ai(port, in.s_addr, hints);
190 		if (*res == NULL)
191 			return (EAI_MEMORY);
192 		return (0);
193 	}
194 
195 	/* Don't try DNS if AI_NUMERICHOST is set */
196 	if (hints && hints->ai_flags & AI_NUMERICHOST)
197 		return (EAI_NONAME);
198 
199 	hp = gethostbyname(hostname);
200 	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
201 		struct addrinfo *cur, *prev;
202 
203 		cur = prev = *res = NULL;
204 		for (i = 0; hp->h_addr_list[i]; i++) {
205 			struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
206 
207 			cur = malloc_ai(port, in->s_addr, hints);
208 			if (cur == NULL) {
209 				if (*res != NULL)
210 					freeaddrinfo(*res);
211 				return (EAI_MEMORY);
212 			}
213 			if (prev)
214 				prev->ai_next = cur;
215 			else
216 				*res = cur;
217 
218 			prev = cur;
219 		}
220 		return (0);
221 	}
222 
223 	return (EAI_NODATA);
224 }
225 #endif /* !HAVE_GETADDRINFO */
226