xref: /freebsd/contrib/ldns/compat/fake-rfc2553.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
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 <ldns/config.h>
40 #include <ldns/common.h>
41 #include <unistd.h>
42 #include <string.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include "compat/fake-rfc2553.h"
46 
47 #ifndef HAVE_GETNAMEINFO
48 int getnameinfo(const struct sockaddr *sa, size_t ATTR_UNUSED(salen), char *host,
49                 size_t hostlen, char *serv, size_t servlen, int flags)
50 {
51 	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
52 	struct hostent *hp;
53 	char tmpserv[16];
54 
55 	if (serv != NULL) {
56 		snprintf(tmpserv, sizeof(tmpserv), "%d", ntohs(sin->sin_port));
57 		if (strlcpy(serv, tmpserv, servlen) >= servlen)
58 			return (EAI_MEMORY);
59 	}
60 
61 	if (host != NULL) {
62 		if (flags & NI_NUMERICHOST) {
63 			if (strlcpy(host, inet_ntoa(sin->sin_addr),
64 			    hostlen) >= hostlen)
65 				return (EAI_MEMORY);
66 			else
67 				return (0);
68 		} else {
69 			hp = gethostbyaddr((char *)&sin->sin_addr,
70 			    sizeof(struct in_addr), AF_INET);
71 			if (hp == NULL)
72 				return (EAI_NODATA);
73 
74 			if (strlcpy(host, hp->h_name, hostlen) >= hostlen)
75 				return (EAI_MEMORY);
76 			else
77 				return (0);
78 		}
79 	}
80 	return (0);
81 }
82 #endif /* !HAVE_GETNAMEINFO */
83 
84 #ifndef HAVE_GAI_STRERROR
85 #ifdef HAVE_CONST_GAI_STRERROR_PROTO
86 const char *
87 #else
88 char *
89 #endif
90 gai_strerror(int err)
91 {
92 	switch (err) {
93 	case EAI_NODATA:
94 		return ("no address associated with name");
95 	case EAI_MEMORY:
96 		return ("memory allocation failure.");
97 	case EAI_NONAME:
98 		return ("nodename nor servname provided, or not known");
99 	default:
100 		return ("unknown/invalid error.");
101 	}
102 }
103 #endif /* !HAVE_GAI_STRERROR */
104 
105 #ifndef HAVE_FREEADDRINFO
106 void
107 freeaddrinfo(struct addrinfo *ai)
108 {
109 	struct addrinfo *next;
110 
111 	for(; ai != NULL;) {
112 		next = ai->ai_next;
113 		free(ai);
114 		ai = next;
115 	}
116 }
117 #endif /* !HAVE_FREEADDRINFO */
118 
119 #ifndef HAVE_GETADDRINFO
120 static struct
121 addrinfo *malloc_ai(int port, u_long addr, const struct addrinfo *hints)
122 {
123 	struct addrinfo *ai;
124 
125 	ai = malloc(sizeof(*ai) + sizeof(struct sockaddr_in));
126 	if (ai == NULL)
127 		return (NULL);
128 
129 	memset(ai, '\0', sizeof(*ai) + sizeof(struct sockaddr_in));
130 
131 	ai->ai_addr = (struct sockaddr *)(ai + 1);
132 	/* XXX -- ssh doesn't use sa_len */
133 	ai->ai_addrlen = sizeof(struct sockaddr_in);
134 	ai->ai_addr->sa_family = ai->ai_family = AF_INET;
135 
136 	((struct sockaddr_in *)(ai)->ai_addr)->sin_port = port;
137 	((struct sockaddr_in *)(ai)->ai_addr)->sin_addr.s_addr = addr;
138 
139 	/* XXX: the following is not generally correct, but does what we want */
140 	if (hints->ai_socktype)
141 		ai->ai_socktype = hints->ai_socktype;
142 	else
143 		ai->ai_socktype = SOCK_STREAM;
144 
145 	if (hints->ai_protocol)
146 		ai->ai_protocol = hints->ai_protocol;
147 
148 	return (ai);
149 }
150 
151 int
152 getaddrinfo(const char *hostname, const char *servname,
153     const struct addrinfo *hints, struct addrinfo **res)
154 {
155 	struct hostent *hp;
156 	struct servent *sp;
157 	struct in_addr in;
158 	int i;
159 	long int port;
160 	u_long addr;
161 
162 	port = 0;
163 	if (servname != NULL) {
164 		char *cp;
165 
166 		port = strtol(servname, &cp, 10);
167 		if (port > 0 && port <= 65535 && *cp == '\0')
168 			port = htons(port);
169 		else if ((sp = getservbyname(servname, NULL)) != NULL)
170 			port = sp->s_port;
171 		else
172 			port = 0;
173 	}
174 
175 	if (hints && hints->ai_flags & AI_PASSIVE) {
176 		addr = htonl(0x00000000);
177 		if (hostname && inet_aton(hostname, &in) != 0)
178 			addr = in.s_addr;
179 		*res = malloc_ai(port, addr, hints);
180 		if (*res == NULL)
181 			return (EAI_MEMORY);
182 		return (0);
183 	}
184 
185 	if (!hostname) {
186 		*res = malloc_ai(port, htonl(0x7f000001), hints);
187 		if (*res == NULL)
188 			return (EAI_MEMORY);
189 		return (0);
190 	}
191 
192 	if (inet_aton(hostname, &in)) {
193 		*res = malloc_ai(port, in.s_addr, hints);
194 		if (*res == NULL)
195 			return (EAI_MEMORY);
196 		return (0);
197 	}
198 
199 	/* Don't try DNS if AI_NUMERICHOST is set */
200 	if (hints && hints->ai_flags & AI_NUMERICHOST)
201 		return (EAI_NONAME);
202 
203 	hp = gethostbyname(hostname);
204 	if (hp && hp->h_name && hp->h_name[0] && hp->h_addr_list[0]) {
205 		struct addrinfo *cur, *prev;
206 
207 		cur = prev = *res = NULL;
208 		for (i = 0; hp->h_addr_list[i]; i++) {
209 			struct in_addr *in = (struct in_addr *)hp->h_addr_list[i];
210 
211 			cur = malloc_ai(port, in->s_addr, hints);
212 			if (cur == NULL) {
213 				if (*res != NULL)
214 					freeaddrinfo(*res);
215 				return (EAI_MEMORY);
216 			}
217 			if (prev)
218 				prev->ai_next = cur;
219 			else
220 				*res = cur;
221 
222 			prev = cur;
223 		}
224 		return (0);
225 	}
226 
227 	return (EAI_NODATA);
228 }
229 #endif /* !HAVE_GETADDRINFO */
230