xref: /illumos-gate/usr/src/lib/nsswitch/nis/common/getnetent.c (revision 581cede61ac9c14d8d4ea452562a567189eead78)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /*
27  *	nis/getnetent.c -- "nis" backend for nsswitch "networks" database
28  */
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #include "nis_common.h"
33 #include <synch.h>
34 #include <netdb.h>
35 #include <sys/socket.h>
36 #include <netinet/in.h>
37 #include <arpa/inet.h>
38 #include <string.h>
39 
40 static int nettoa(int anet, char *buf, int buflen, char **pnull);
41 
42 static nss_status_t
43 getbyname(be, a)
44 	nis_backend_ptr_t	be;
45 	void			*a;
46 {
47 	nss_XbyY_args_t		*argp = (nss_XbyY_args_t *)a;
48 
49 	return (_nss_nis_lookup(be, argp, 1, "networks.byname",
50 		argp->key.name, 0));
51 }
52 
53 static nss_status_t
54 getbyaddr(be, a)
55 	nis_backend_ptr_t	be;
56 	void			*a;
57 {
58 	nss_XbyY_args_t		*argp = (nss_XbyY_args_t *)a;
59 	char			addrstr[16];
60 	char			*pnull;
61 	nss_status_t		rc;
62 
63 	if (nettoa((int)argp->key.netaddr.net, addrstr, 16, &pnull) != 0)
64 		return (NSS_UNAVAIL);	/* it's really ENOMEM */
65 	rc = _nss_nis_lookup(be, argp, 1, "networks.byaddr", addrstr, 0);
66 
67 	/*
68 	 * if not found, try again with the untruncated address string
69 	 * that has the trailing zero(s)
70 	 */
71 	if (rc == NSS_NOTFOUND && pnull != NULL) {
72 		*pnull = '.';
73 		rc = _nss_nis_lookup(be, argp, 1, "networks.byaddr",
74 			addrstr, 0);
75 	}
76 	return (rc);
77 }
78 
79 static nis_backend_op_t net_ops[] = {
80 	_nss_nis_destr,
81 	_nss_nis_endent,
82 	_nss_nis_setent,
83 	_nss_nis_getent_netdb,
84 	getbyname,
85 	getbyaddr
86 };
87 
88 /*ARGSUSED*/
89 nss_backend_t *
90 _nss_nis_networks_constr(dummy1, dummy2, dummy3)
91 	const char	*dummy1, *dummy2, *dummy3;
92 {
93 	return (_nss_nis_constr(net_ops,
94 				sizeof (net_ops) / sizeof (net_ops[0]),
95 				"networks.byaddr"));
96 }
97 
98 /*
99  * Takes an unsigned integer in host order, and returns a printable
100  * string for it as a network number.  To allow for the possibility of
101  * naming subnets, only trailing dot-zeros are truncated. The location
102  * where the string is truncated (or set to '\0') is returned in *pnull.
103  */
104 static int
105 nettoa(int anet, char *buf, int buflen, char **pnull)
106 {
107 	char *p;
108 	struct in_addr in;
109 	int addr;
110 
111 	*pnull = NULL;
112 
113 	if (buf == 0)
114 		return (1);
115 	in = inet_makeaddr(anet, INADDR_ANY);
116 	addr = in.s_addr;
117 	(void) strncpy(buf, inet_ntoa(in), buflen);
118 	if ((IN_CLASSA_HOST & htonl(addr)) == 0) {
119 		p = strchr(buf, '.');
120 		if (p == NULL)
121 			return (1);
122 		*p = 0;
123 		*pnull = p;
124 	} else if ((IN_CLASSB_HOST & htonl(addr)) == 0) {
125 		p = strchr(buf, '.');
126 		if (p == NULL)
127 			return (1);
128 		p = strchr(p+1, '.');
129 		if (p == NULL)
130 			return (1);
131 		*p = 0;
132 		*pnull = p;
133 	} else if ((IN_CLASSC_HOST & htonl(addr)) == 0) {
134 		p = strrchr(buf, '.');
135 		if (p == NULL)
136 			return (1);
137 		*p = 0;
138 		*pnull = p;
139 	}
140 	return (0);
141 }
142