xref: /openbsd-src/lib/libc/asr/getnetnamadr.c (revision 1ed934d0d08bf9c3f460e8740d169e7606f8702f)
1 /*	$OpenBSD: getnetnamadr.c,v 1.5 2013/05/27 17:31:01 eric Exp $	*/
2 /*
3  * Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <netinet/in.h>
20 
21 #include <errno.h>
22 #include <resolv.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 #include "asr.h"
27 
28 static void _fillnetent(const struct netent *, struct netent *, char *buf,
29     size_t);
30 
31 static struct netent	 _netent;
32 static char		 _entbuf[4096];
33 
34 static char *_empty[] = { NULL, };
35 
36 static void
37 _fillnetent(const struct netent *e, struct netent *r, char *buf, size_t len)
38 {
39 	char	**ptr, *end, *pos;
40 	size_t	n, i;
41 	int	naliases;
42 
43 	bzero(buf, len);
44 	bzero(r, sizeof(*r));
45 	r->n_aliases = _empty;
46 
47 	end = buf + len;
48 	ptr = (char **)ALIGN(buf);
49 
50 	if ((char *)ptr >= end)
51 		return;
52 
53 	for (naliases = 0; e->n_aliases[naliases]; naliases++)
54 		;
55 
56 	r->n_name = NULL;
57 	r->n_addrtype = e->n_addrtype;
58 	r->n_net = e->n_net;
59 	r->n_aliases = ptr;
60 
61 	pos = (char *)(ptr + (naliases + 1));
62 	if (pos > end)
63 		r->n_aliases = _empty;
64 
65 	n = strlcpy(pos, e->n_name, end - pos);
66 	if (n >= end - pos)
67 		return;
68 	r->n_name = pos;
69 	pos += n + 1;
70 
71 	for (i = 0; i < naliases; i++) {
72 		n = strlcpy(pos, e->n_aliases[i], end - pos);
73 		if (n >= end - pos)
74 			return;
75 		r->n_aliases[i] = pos;
76 		pos += n + 1;
77 	}
78 }
79 
80 struct netent *
81 getnetbyname(const char *name)
82 {
83 	struct async	*as;
84 	struct async_res ar;
85 
86 	res_init();
87 
88 	as = getnetbyname_async(name, NULL);
89 	if (as == NULL) {
90 		h_errno = NETDB_INTERNAL;
91 		return (NULL);
92 	}
93 
94 	async_run_sync(as, &ar);
95 
96 	errno = ar.ar_errno;
97 	h_errno = ar.ar_h_errno;
98 	if (ar.ar_netent == NULL)
99 		return (NULL);
100 
101 	_fillnetent(ar.ar_netent, &_netent, _entbuf, sizeof(_entbuf));
102 	free(ar.ar_netent);
103 
104 	return (&_netent);
105 }
106 
107 struct netent *
108 getnetbyaddr(in_addr_t net, int type)
109 {
110 	struct async	*as;
111 	struct async_res ar;
112 
113 	res_init();
114 
115 	as = getnetbyaddr_async(net, type, NULL);
116 	if (as == NULL) {
117 		h_errno = NETDB_INTERNAL;
118 		return (NULL);
119 	}
120 
121 	async_run_sync(as, &ar);
122 
123 	errno = ar.ar_errno;
124 	h_errno = ar.ar_h_errno;
125 	if (ar.ar_netent == NULL)
126 		return (NULL);
127 
128 	_fillnetent(ar.ar_netent, &_netent, _entbuf, sizeof(_entbuf));
129 	free(ar.ar_netent);
130 
131 	return (&_netent);
132 }
133