xref: /titanic_41/usr/src/lib/libnsl/nss/gethostbyname_r.c (revision 6451fdbca2f79129a3a09d2fe3f6dd4d062bebff)
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 2005 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  * lib/libnsl/nss/gethostbyname_r.c
32  *
33  * gethostbyname_r() is defined in this file.  It is implemented on top of
34  *   _get_hostserv_inetnetdir_byname() which is also used to implement
35  *   netdir_getbyname() for inet family transports.  In turn the common code
36  *   uses the name service switch policy for "hosts" and "services" unless
37  *   the administrator chooses to bypass the name service switch by
38  *   specifying third-party supplied nametoaddr libs for inet transports
39  *   in /etc/netconfig.
40  *
41  * gethostbyaddr_r() is similarly related to _get_hostserv_inetnetdir_byaddr()
42  *   and netdir_getbyaddr();
43  *
44  * The common code lives in netdir_inet.c.
45  *
46  * gethostent_r(), sethostent() and endhostent() are *not* implemented on top
47  *   of the common interface;  they go straight to the switch and are
48  *   defined in gethostent_r.c.
49  *
50  * There is absolutely no data sharing, not even the stayopen flag or
51  *   enumeration state, between gethostbyYY_r() and gethostent_r();
52  */
53 
54 #include <netdb.h>
55 #include <netdir.h>
56 #include <sys/types.h>
57 #include <nss_netdir.h>
58 #include <string.h>
59 
60 extern struct netconfig *__rpc_getconfip();
61 
62 /*
63  * h_errno POLICY: The frontends expect the name service
64  * backends to modify the h_errno in "arg"; _switch_gethostbyYY_r()
65  * will copy that over onto user's h_errnop pointer. This h_errno is
66  * never used for "switching" -- status from nss_search serves
67  * the purpose. There is no explicit zeroing in the case of success.
68  */
69 
70 extern struct hostent *
71 _switch_gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
72 	int buflen, int *h_errnop);
73 
74 extern struct hostent *
75 _switch_gethostbyaddr_r(const char *addr, int length, int type,
76 	struct hostent *result, char *buffer, int buflen, int *h_errnop);
77 
78 #ifdef PIC
79 struct hostent *
80 _uncached_gethostbyname_r(const char *nam, struct hostent *result,
81 	char *buffer, int buflen, int *h_errnop)
82 {
83 	return (_switch_gethostbyname_r(nam, result,
84 	buffer, buflen, h_errnop));
85 }
86 
87 struct hostent *
88 _uncached_gethostbyaddr_r(const char *addr, int length, int type,
89 	struct hostent *result, char *buffer, int buflen, int *h_errnop)
90 {
91 	return (_switch_gethostbyaddr_r(addr, length, type,
92 					result, buffer, buflen, h_errnop));
93 }
94 
95 #endif
96 
97 extern struct hostent *
98 gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
99 	int buflen, int *h_errnop);
100 
101 extern struct hostent *
102 gethostbyaddr_r(const char *addr, int length, int type,
103 	struct hostent *result, char *buffer, int buflen, int *h_errnop);
104 
105 struct hostent *
106 gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
107 	int buflen, int *h_errnop)
108 {
109 	struct netconfig *nconf;
110 	struct	nss_netdirbyname_in nssin;
111 	union	nss_netdirbyname_out nssout;
112 	int neterr, dummy;
113 
114 	if (h_errnop == NULL)
115 		h_errnop = &dummy;
116 
117 	if (strlen(nam) == 0) {
118 		*h_errnop = HOST_NOT_FOUND;
119 		return (NULL);
120 	}
121 
122 	if ((nconf = __rpc_getconfip("udp")) == NULL &&
123 	    (nconf = __rpc_getconfip("tcp")) == NULL) {
124 		*h_errnop = NO_RECOVERY;
125 		return (NULL);
126 	}
127 
128 	nssin.op_t = NSS_HOST;
129 	nssin.arg.nss.host.name = nam;
130 	nssin.arg.nss.host.buf = buffer;
131 	nssin.arg.nss.host.buflen = buflen;
132 
133 	nssout.nss.host.hent = result;
134 	nssout.nss.host.herrno_p = h_errnop;
135 
136 	/*
137 	 * We pass in nconf and let the implementation of the long-named func
138 	 * decide whether to use the switch based on nc_nlookups.
139 	 */
140 	neterr = _get_hostserv_inetnetdir_byname(nconf, &nssin, &nssout);
141 
142 	(void) freenetconfigent(nconf);
143 	if (neterr != ND_OK)
144 		return (NULL);
145 	return (nssout.nss.host.hent);
146 }
147 
148 struct hostent *
149 gethostbyaddr_r(const char *addr, int length, int type,
150 	struct hostent *result, char *buffer, int buflen, int *h_errnop)
151 {
152 	struct netconfig *nconf;
153 	struct	nss_netdirbyaddr_in nssin;
154 	union	nss_netdirbyaddr_out nssout;
155 	int neterr;
156 
157 	if (type != AF_INET) {
158 		*h_errnop = HOST_NOT_FOUND;
159 		return (NULL);
160 	}
161 
162 	if ((nconf = __rpc_getconfip("udp")) == NULL &&
163 	    (nconf = __rpc_getconfip("tcp")) == NULL) {
164 		*h_errnop = NO_RECOVERY;
165 		return (NULL);
166 	}
167 
168 	nssin.op_t = NSS_HOST;
169 	nssin.arg.nss.host.addr = addr;
170 	nssin.arg.nss.host.len = length;
171 	nssin.arg.nss.host.type = type;
172 	nssin.arg.nss.host.buf = buffer;
173 	nssin.arg.nss.host.buflen = buflen;
174 
175 	nssout.nss.host.hent = result;
176 	nssout.nss.host.herrno_p = h_errnop;
177 
178 	/*
179 	 * We pass in nconf and let the implementation of this long-named func
180 	 * decide whether to use the switch based on nc_nlookups.
181 	 */
182 	neterr = _get_hostserv_inetnetdir_byaddr(nconf, &nssin, &nssout);
183 
184 	(void) freenetconfigent(nconf);
185 	if (neterr != ND_OK)
186 		return (NULL);
187 	return (nssout.nss.host.hent);
188 }
189