getnetnamadr.c revision 3070 
1/*-
2 * Copyright (c) 1994, Garrett Wollman
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23 * SUCH DAMAGE.
24 */
25
26#if defined(LIBC_SCCS) && !defined(lint)
27static char sccsid[] = "@(#)$Id$";
28static char rcsid[] = "$Id$";
29#endif /* LIBC_SCCS and not lint */
30
31#include <sys/param.h>
32#include <sys/socket.h>
33#include <netinet/in.h>
34#include <arpa/inet.h>
35#include <netdb.h>
36#include <stdio.h>
37#include <ctype.h>
38#include <errno.h>
39#include <string.h>
40
41extern struct netent * _getnetbyhtname  __P((const char *));
42extern struct netent * _getnetbydnsname __P((const char *));
43extern struct netent * _getnetbynisname __P((const char *));
44extern struct netent * _getnetbyhtaddr  __P((long, int));
45extern struct netent * _getnetbydnsaddr __P((long, int));
46extern struct netent * _getnetbynisaddr __P((long, int));
47
48#define _PATH_NETCONF	"/etc/net.conf"
49
50enum service_type {
51  SERVICE_NONE = 0,
52  SERVICE_BIND,
53  SERVICE_TABLE,
54  SERVICE_NIS };
55#define SERVICE_MAX	SERVICE_NIS
56
57static struct {
58  const char *name;
59  enum service_type type;
60} service_names[] = {
61  { "nets", SERVICE_TABLE },
62  { "/etc/nets", SERVICE_TABLE },
63  { "nettable", SERVICE_TABLE },
64  { "ntable", SERVICE_TABLE },
65  { "bind", SERVICE_BIND },
66  { "dns", SERVICE_BIND },
67  { "domain", SERVICE_BIND },
68  { "yp", SERVICE_NIS },
69  { "yellowpages", SERVICE_NIS },
70  { "nis", SERVICE_NIS },
71  { 0, SERVICE_NONE }
72};
73
74static enum service_type service_order[SERVICE_MAX + 1];
75static int service_done = 0;
76
77static enum service_type
78get_service_name(const char *name) {
79	int i;
80	for(i = 0; service_names[i].type != SERVICE_NONE; i++) {
81		if(!strcasecmp(name, service_names[i].name)) {
82			return service_names[i].type;
83		}
84	}
85	return SERVICE_NONE;
86}
87
88static void
89init_services()
90{
91	char *cp, buf[BUFSIZ];
92	register int cc = 0;
93	FILE *fd;
94
95	if ((fd = (FILE *)fopen(_PATH_NETCONF, "r")) == NULL) {
96				/* make some assumptions */
97		service_order[0] = SERVICE_TABLE;
98		service_order[1] = SERVICE_NONE;
99	} else {
100		while (fgets(buf, BUFSIZ, fd) != NULL && cc < SERVICE_MAX) {
101			if(buf[0] == '#')
102				continue;
103
104			cp = strtok(buf, "\n \t,:;");
105			do {
106				if(!isalpha(cp[0])) continue;
107				service_order[cc] = get_service_name(buf);
108				if(service_order[cc] != SERVICE_NONE)
109					cc++;
110			} while((cp = strtok((char *)0, "\n \t,:;"))
111				&& (cc < SERVICE_MAX));
112		}
113		service_order[cc] = SERVICE_NONE;
114		fclose(fd);
115	}
116	service_done = 1;
117}
118
119struct netent *
120getnetbyname(const char *name)
121{
122	struct netent *hp = 0;
123	int nserv = 0;
124
125	if (!service_done)
126		init_services();
127
128	while (!hp) {
129		switch (service_order[nserv]) {
130		      case SERVICE_NONE:
131			return NULL;
132		      case SERVICE_TABLE:
133			hp = _getnetbyhtname(name);
134			break;
135		      case SERVICE_BIND:
136			hp = _getnetbydnsname(name);
137			break;
138		      case SERVICE_NIS:
139			hp = _getnetbynisname(name);
140			break;
141		}
142		nserv++;
143	}
144	return hp;
145}
146
147struct netent *
148getnetbyaddr(addr, type)
149	long addr;
150	int type;
151{
152	struct netent *hp = 0;
153	int nserv = 0;
154
155	if (!service_done)
156		init_services();
157
158	while (!hp) {
159		switch (service_order[nserv]) {
160		      case SERVICE_NONE:
161			return 0;
162		      case SERVICE_TABLE:
163			hp = _getnetbyhtaddr(addr, type);
164			break;
165		      case SERVICE_BIND:
166			hp = _getnetbydnsaddr(addr, type);
167			break;
168		      case SERVICE_NIS:
169			hp = _getnetbynisaddr(addr, type);
170			break;
171		}
172		nserv++;
173	}
174	return hp;
175}
176
177void
178setnetent(stayopen)
179	int stayopen;
180{
181	_setnethtent(stayopen);
182	_setnetdnsent(stayopen);
183}
184
185void
186endnetent()
187{
188	_endnethtent();
189	_endnetdnsent();
190}
191