xref: /titanic_41/usr/src/lib/libnsl/nss/gethostbyname_r.c (revision 7c3666b49413f8605b61f47314242cbc4a9244e5)
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 
59 extern 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 
69 extern struct hostent *
70 _switch_gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
71 	int buflen, int *h_errnop);
72 
73 extern 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
78 struct 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 
86 struct 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 
96 extern struct hostent *
97 gethostbyname_r(const char *nam, struct hostent *result, char *buffer,
98 	int buflen, int *h_errnop);
99 
100 extern struct hostent *
101 gethostbyaddr_r(const char *addr, int length, int type,
102 	struct hostent *result, char *buffer, int buflen, int *h_errnop);
103 
104 struct hostent *
105 gethostbyname_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 
147 struct hostent *
148 gethostbyaddr_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