xref: /titanic_50/usr/src/lib/libnsl/nss/gethostbyname_r.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
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  * Copyright 2003 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  * lib/libnsl/nss/gethostbyname_r.c
31  *
32  * gethostbyname_r() is defined in this file.  It is implemented on top of
33  *   _get_hostserv_inetnetdir_byname() which is also used to implement
34  *   netdir_getbyname() for inet family transports.  In turn the common code
35  *   uses the name service switch policy for "hosts" and "services" unless
36  *   the administrator chooses to bypass the name service switch by
37  *   specifying third-party supplied nametoaddr libs for inet transports
38  *   in /etc/netconfig.
39  *
40  * gethostbyaddr_r() is similarly related to _get_hostserv_inetnetdir_byaddr()
41  *   and netdir_getbyaddr();
42  *
43  * The common code lives in netdir_inet.c.
44  *
45  * gethostent_r(), sethostent() and endhostent() are *not* implemented on top
46  *   of the common interface;  they go straight to the switch and are
47  *   defined in gethostent_r.c.
48  *
49  * There is absolutely no data sharing, not even the stayopen flag or
50  *   enumeration state, between gethostbyYY_r() and gethostent_r();
51  */
52 
53 #include <netdb.h>
54 #include <rpc/trace.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 	trace2(TR_gethostbyname_r, 0, buflen);
115 
116 	if (h_errnop == NULL)
117 		h_errnop = &dummy;
118 
119 	if (strlen(nam) == 0) {
120 		*h_errnop = HOST_NOT_FOUND;
121 		trace2(TR_gethostbyname_r, 1, buflen);
122 		return ((struct hostent *)NULL);
123 	}
124 
125 	if ((nconf = __rpc_getconfip("udp")) == NULL &&
126 	    (nconf = __rpc_getconfip("tcp")) == NULL) {
127 		*h_errnop = NO_RECOVERY;
128 		trace2(TR_gethostbyname_r, 1, buflen);
129 		return ((struct hostent *)NULL);
130 	}
131 
132 	nssin.op_t = NSS_HOST;
133 	nssin.arg.nss.host.name = nam;
134 	nssin.arg.nss.host.buf = buffer;
135 	nssin.arg.nss.host.buflen = buflen;
136 
137 	nssout.nss.host.hent = result;
138 	nssout.nss.host.herrno_p = h_errnop;
139 
140 	/*
141 	 * We pass in nconf and let the implementation of the long-named func
142 	 * decide whether to use the switch based on nc_nlookups.
143 	 */
144 	neterr = _get_hostserv_inetnetdir_byname(nconf, &nssin, &nssout);
145 
146 	(void) freenetconfigent(nconf);
147 	if (neterr != ND_OK) {
148 		trace2(TR_gethostbyname_r, 1, buflen);
149 		return ((struct hostent *)NULL);
150 	}
151 	trace2(TR_gethostbyname_r, 1, buflen);
152 	return (nssout.nss.host.hent);
153 }
154 
155 struct hostent *
156 gethostbyaddr_r(const char *addr, int length, int type,
157 	struct hostent *result, char *buffer, int buflen, int *h_errnop)
158 {
159 	struct netconfig *nconf;
160 	struct	nss_netdirbyaddr_in nssin;
161 	union	nss_netdirbyaddr_out nssout;
162 	int neterr;
163 
164 	trace3(TR_gethostbyaddr_r, 0, length, buflen);
165 
166 	if (type != AF_INET) {
167 		*h_errnop = HOST_NOT_FOUND;
168 		return ((struct hostent *)NULL);
169 	}
170 
171 	if ((nconf = __rpc_getconfip("udp")) == NULL &&
172 	    (nconf = __rpc_getconfip("tcp")) == NULL) {
173 		*h_errnop = NO_RECOVERY;
174 		trace3(TR_gethostbyaddr_r, 0, length, buflen);
175 		return ((struct hostent *)NULL);
176 	}
177 
178 	nssin.op_t = NSS_HOST;
179 	nssin.arg.nss.host.addr = addr;
180 	nssin.arg.nss.host.len = length;
181 	nssin.arg.nss.host.type = type;
182 	nssin.arg.nss.host.buf = buffer;
183 	nssin.arg.nss.host.buflen = buflen;
184 
185 	nssout.nss.host.hent = result;
186 	nssout.nss.host.herrno_p = h_errnop;
187 
188 	/*
189 	 * We pass in nconf and let the implementation of this long-named func
190 	 * decide whether to use the switch based on nc_nlookups.
191 	 */
192 	neterr = _get_hostserv_inetnetdir_byaddr(nconf, &nssin, &nssout);
193 
194 	(void) freenetconfigent(nconf);
195 	if (neterr != ND_OK) {
196 		trace3(TR_gethostbyaddr_r, 0, length, buflen);
197 		return ((struct hostent *)NULL);
198 	}
199 	return (nssout.nss.host.hent);
200 }
201