gethostbyname_r.c revision 1219:f89f56c2d9ac 
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, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23/*
24 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25 * Use is subject to license terms.
26 */
27
28#pragma ident	"%Z%%M%	%I%	%E% SMI"
29
30/*
31 * gethostbyname_r() is defined in this file.  It is implemented on top of
32 *   _get_hostserv_inetnetdir_byname() which is also used to implement
33 *   netdir_getbyname() for inet family transports.  In turn the common code
34 *   uses the name service switch policy for "hosts" and "services" unless
35 *   the administrator chooses to bypass the name service switch by
36 *   specifying third-party supplied nametoaddr libs for inet transports
37 *   in /etc/netconfig.
38 *
39 * gethostbyaddr_r() is similarly related to _get_hostserv_inetnetdir_byaddr()
40 *   and netdir_getbyaddr();
41 *
42 * The common code lives in netdir_inet.c.
43 *
44 * gethostent_r(), sethostent() and endhostent() are *not* implemented on top
45 *   of the common interface;  they go straight to the switch and are
46 *   defined in gethostent_r.c.
47 *
48 * There is absolutely no data sharing, not even the stayopen flag or
49 *   enumeration state, between gethostbyYY_r() and gethostent_r();
50 */
51
52#include "mt.h"
53#include <netdb.h>
54#include <netdir.h>
55#include <sys/types.h>
56#include <nss_netdir.h>
57#include <string.h>
58
59extern struct netconfig *__rpc_getconfip();
60
61/*
62 * h_errno POLICY: The frontends expect the name service
63 * backends to modify the h_errno in "arg"; _switch_gethostbyYY_r()
64 * will copy that over onto user's h_errnop pointer. This h_errno is
65 * never used for "switching" -- status from nss_search serves
66 * the purpose. There is no explicit zeroing in the case of success.
67 */
68
69extern struct hostent *
70_switch_gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
71	int buflen, int *h_errnop);
72
73extern struct hostent *
74_switch_gethostbyaddr_r(const char *addr, int length, int type,
75	struct hostent *result, char *buffer, int buflen, int *h_errnop);
76
77#ifdef PIC
78struct hostent *
79_uncached_gethostbyname_r(const char *nam, struct hostent *result,
80	char *buffer, int buflen, int *h_errnop)
81{
82	return (_switch_gethostbyname_r(nam, result,
83	buffer, buflen, h_errnop));
84}
85
86struct hostent *
87_uncached_gethostbyaddr_r(const char *addr, int length, int type,
88	struct hostent *result, char *buffer, int buflen, int *h_errnop)
89{
90	return (_switch_gethostbyaddr_r(addr, length, type,
91					result, buffer, buflen, h_errnop));
92}
93
94#endif
95
96extern struct hostent *
97gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
98	int buflen, int *h_errnop);
99
100extern struct hostent *
101gethostbyaddr_r(const char *addr, int length, int type,
102	struct hostent *result, char *buffer, int buflen, int *h_errnop);
103
104struct hostent *
105gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
106	int buflen, int *h_errnop)
107{
108	struct netconfig *nconf;
109	struct	nss_netdirbyname_in nssin;
110	union	nss_netdirbyname_out nssout;
111	int neterr, dummy;
112
113	if (h_errnop == NULL)
114		h_errnop = &dummy;
115
116	if (strlen(nam) == 0) {
117		*h_errnop = HOST_NOT_FOUND;
118		return (NULL);
119	}
120
121	if ((nconf = __rpc_getconfip("udp")) == NULL &&
122	    (nconf = __rpc_getconfip("tcp")) == NULL) {
123		*h_errnop = NO_RECOVERY;
124		return (NULL);
125	}
126
127	nssin.op_t = NSS_HOST;
128	nssin.arg.nss.host.name = nam;
129	nssin.arg.nss.host.buf = buffer;
130	nssin.arg.nss.host.buflen = buflen;
131
132	nssout.nss.host.hent = result;
133	nssout.nss.host.herrno_p = h_errnop;
134
135	/*
136	 * We pass in nconf and let the implementation of the long-named func
137	 * decide whether to use the switch based on nc_nlookups.
138	 */
139	neterr = _get_hostserv_inetnetdir_byname(nconf, &nssin, &nssout);
140
141	(void) freenetconfigent(nconf);
142	if (neterr != ND_OK)
143		return (NULL);
144	return (nssout.nss.host.hent);
145}
146
147struct hostent *
148gethostbyaddr_r(const char *addr, int length, int type,
149	struct hostent *result, char *buffer, int buflen, int *h_errnop)
150{
151	struct netconfig *nconf;
152	struct	nss_netdirbyaddr_in nssin;
153	union	nss_netdirbyaddr_out nssout;
154	int neterr;
155
156	if (type != AF_INET) {
157		*h_errnop = HOST_NOT_FOUND;
158		return (NULL);
159	}
160
161	if ((nconf = __rpc_getconfip("udp")) == NULL &&
162	    (nconf = __rpc_getconfip("tcp")) == NULL) {
163		*h_errnop = NO_RECOVERY;
164		return (NULL);
165	}
166
167	nssin.op_t = NSS_HOST;
168	nssin.arg.nss.host.addr = addr;
169	nssin.arg.nss.host.len = length;
170	nssin.arg.nss.host.type = type;
171	nssin.arg.nss.host.buf = buffer;
172	nssin.arg.nss.host.buflen = buflen;
173
174	nssout.nss.host.hent = result;
175	nssout.nss.host.herrno_p = h_errnop;
176
177	/*
178	 * We pass in nconf and let the implementation of this long-named func
179	 * decide whether to use the switch based on nc_nlookups.
180	 */
181	neterr = _get_hostserv_inetnetdir_byaddr(nconf, &nssin, &nssout);
182
183	(void) freenetconfigent(nconf);
184	if (neterr != ND_OK)
185		return (NULL);
186	return (nssout.nss.host.hent);
187}
188