gethostbyname_r.c revision 2830:5228d1267a01 
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 2006 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29/*
30 * gethostbyname_r() is defined in this file.  It is implemented on top of
31 *   _get_hostserv_inetnetdir_byname() which is also used to implement
32 *   netdir_getbyname() for inet family transports.  In turn the common code
33 *   uses the name service switch policy for "hosts" and "services" unless
34 *   the administrator chooses to bypass the name service switch by
35 *   specifying third-party supplied nametoaddr libs for inet transports
36 *   in /etc/netconfig.
37 *
38 * gethostbyaddr_r() is similarly related to _get_hostserv_inetnetdir_byaddr()
39 *   and netdir_getbyaddr();
40 *
41 * The common code lives in netdir_inet.c.
42 *
43 * gethostent_r(), sethostent() and endhostent() are *not* implemented on top
44 *   of the common interface;  they go straight to the switch and are
45 *   defined in gethostent_r.c.
46 *
47 * There is absolutely no data sharing, not even the stayopen flag or
48 *   enumeration state, between gethostbyYY_r() and gethostent_r();
49 */
50
51#include "mt.h"
52#include <netdb.h>
53#include <netdir.h>
54#include <sys/types.h>
55#include <nss_netdir.h>
56#include <string.h>
57
58extern struct netconfig *__rpc_getconfip();
59
60/*
61 * h_errno POLICY: The frontends expect the name service
62 * backends to modify the h_errno in "arg"; _switch_gethostbyYY_r()
63 * will copy that over onto user's h_errnop pointer. This h_errno is
64 * never used for "switching" -- status from nss_search serves
65 * the purpose. There is no explicit zeroing in the case of success.
66 */
67
68extern struct hostent *
69_switch_gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
70	int buflen, int *h_errnop);
71
72extern struct hostent *
73_switch_gethostbyaddr_r(const char *addr, int length, int type,
74	struct hostent *result, char *buffer, int buflen, int *h_errnop);
75
76#ifdef PIC
77struct hostent *
78_uncached_gethostbyname_r(const char *nam, struct hostent *result,
79	char *buffer, int buflen, int *h_errnop)
80{
81	return (_switch_gethostbyname_r(nam, result,
82	buffer, buflen, h_errnop));
83}
84
85struct hostent *
86_uncached_gethostbyaddr_r(const char *addr, int length, int type,
87	struct hostent *result, char *buffer, int buflen, int *h_errnop)
88{
89	return (_switch_gethostbyaddr_r(addr, length, type,
90					result, buffer, buflen, h_errnop));
91}
92
93#endif
94
95extern struct hostent *
96gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
97	int buflen, int *h_errnop);
98
99extern struct hostent *
100gethostbyaddr_r(const char *addr, int length, int type,
101	struct hostent *result, char *buffer, int buflen, int *h_errnop);
102
103struct hostent *
104gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
105	int buflen, int *h_errnop)
106{
107	struct netconfig *nconf;
108	struct	nss_netdirbyname_in nssin;
109	union	nss_netdirbyname_out nssout;
110	int neterr, dummy;
111
112	if (h_errnop == NULL)
113		h_errnop = &dummy;
114
115	if (strlen(nam) == 0) {
116		*h_errnop = HOST_NOT_FOUND;
117		return (NULL);
118	}
119
120	if ((nconf = __rpc_getconfip("udp")) == NULL &&
121	    (nconf = __rpc_getconfip("tcp")) == NULL) {
122		*h_errnop = NO_RECOVERY;
123		return (NULL);
124	}
125
126	nssin.op_t = NSS_HOST;
127	nssin.arg.nss.host.name = nam;
128	nssin.arg.nss.host.buf = buffer;
129	nssin.arg.nss.host.buflen = buflen;
130
131	nssout.nss.host.hent = result;
132	nssout.nss.host.herrno_p = h_errnop;
133
134	/*
135	 * We pass in nconf and let the implementation of the long-named func
136	 * decide whether to use the switch based on nc_nlookups.
137	 */
138	neterr = _get_hostserv_inetnetdir_byname(nconf, &nssin, &nssout);
139
140	(void) freenetconfigent(nconf);
141	if (neterr != ND_OK)
142		return (NULL);
143	return (nssout.nss.host.hent);
144}
145
146struct hostent *
147gethostbyaddr_r(const char *addr, int length, int type,
148	struct hostent *result, char *buffer, int buflen, int *h_errnop)
149{
150	struct netconfig *nconf;
151	struct	nss_netdirbyaddr_in nssin;
152	union	nss_netdirbyaddr_out nssout;
153	int neterr, dummy;
154
155	if (h_errnop == NULL)
156		h_errnop = &dummy;
157
158	if (type != AF_INET) {
159		*h_errnop = HOST_NOT_FOUND;
160		return (NULL);
161	}
162
163	if ((nconf = __rpc_getconfip("udp")) == NULL &&
164	    (nconf = __rpc_getconfip("tcp")) == NULL) {
165		*h_errnop = NO_RECOVERY;
166		return (NULL);
167	}
168
169	nssin.op_t = NSS_HOST;
170	nssin.arg.nss.host.addr = addr;
171	nssin.arg.nss.host.len = length;
172	nssin.arg.nss.host.type = type;
173	nssin.arg.nss.host.buf = buffer;
174	nssin.arg.nss.host.buflen = buflen;
175
176	nssout.nss.host.hent = result;
177	nssout.nss.host.herrno_p = h_errnop;
178
179	/*
180	 * We pass in nconf and let the implementation of this long-named func
181	 * decide whether to use the switch based on nc_nlookups.
182	 */
183	neterr = _get_hostserv_inetnetdir_byaddr(nconf, &nssin, &nssout);
184
185	(void) freenetconfigent(nconf);
186	if (neterr != ND_OK)
187		return (NULL);
188	return (nssout.nss.host.hent);
189}
190