yplib.c revision 1.23 1 /* $NetBSD: yplib.c,v 1.23 1996/05/23 13:49:04 christos Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993 Theo de Raadt <deraadt (at) fsa.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Theo de Raadt.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #if defined(LIBC_SCCS) && !defined(lint)
35 static char rcsid[] = "$NetBSD: yplib.c,v 1.23 1996/05/23 13:49:04 christos Exp $";
36 #endif
37
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/socket.h>
41 #include <sys/file.h>
42 #include <sys/uio.h>
43 #include <errno.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 #include <rpc/rpc.h>
49 #include <rpc/xdr.h>
50 #include <rpcsvc/yp_prot.h>
51 #include <rpcsvc/ypclnt.h>
52
53 #define BINDINGDIR "/var/yp/binding"
54 #define YPBINDLOCK "/var/run/ypbind.lock"
55
56 struct dom_binding *_ypbindlist;
57 char _yp_domain[MAXHOSTNAMELEN];
58
59 struct timeval _yplib_timeout = { 10, 0 };
60 int _yplib_nerrs = 5;
61
62 void _yp_unbind __P((struct dom_binding *));
63
64 int
65 _yp_dobind(dom, ypdb)
66 const char *dom;
67 struct dom_binding **ypdb;
68 {
69 static int pid = -1;
70 char path[MAXPATHLEN];
71 struct dom_binding *ysd, *ysd2;
72 struct ypbind_resp ypbr;
73 struct sockaddr_in clnt_sin;
74 int clnt_sock, fd, gpid;
75 CLIENT *client;
76 int new = 0, r;
77 int count = 0;
78
79 if (dom == NULL || *dom == 0)
80 return YPERR_BADARGS;
81
82 /*
83 * test if YP is running or not
84 */
85 if ((fd = open(YPBINDLOCK, O_RDONLY)) == -1)
86 return YPERR_YPBIND;
87 if (!(flock(fd, LOCK_EX | LOCK_NB) == -1 && errno == EWOULDBLOCK)) {
88 (void)close(fd);
89 return YPERR_YPBIND;
90 }
91 (void)close(fd);
92
93 gpid = getpid();
94 if (!(pid == -1 || pid == gpid)) {
95 ysd = _ypbindlist;
96 while (ysd) {
97 if (ysd->dom_client)
98 clnt_destroy(ysd->dom_client);
99 ysd2 = ysd->dom_pnext;
100 free(ysd);
101 ysd = ysd2;
102 }
103 _ypbindlist = NULL;
104 }
105 pid = gpid;
106
107 if (ypdb != NULL)
108 *ypdb = NULL;
109
110 for (ysd = _ypbindlist; ysd; ysd = ysd->dom_pnext)
111 if (strcmp(dom, ysd->dom_domain) == 0)
112 break;
113 if (ysd == NULL) {
114 if ((ysd = malloc(sizeof *ysd)) == NULL)
115 return YPERR_YPERR;
116 (void)memset(ysd, 0, sizeof *ysd);
117 ysd->dom_socket = -1;
118 ysd->dom_vers = 0;
119 new = 1;
120 }
121 again:
122 if (ysd->dom_vers == 0) {
123 (void) snprintf(path, sizeof(path), "%s/%s.%d",
124 BINDINGDIR, dom, 2);
125 if ((fd = open(path, O_RDONLY)) == -1) {
126 /*
127 * no binding file, YP is dead, or not yet fully
128 * alive.
129 */
130 goto trynet;
131 }
132 if (flock(fd, LOCK_EX | LOCK_NB) == -1 &&
133 errno == EWOULDBLOCK) {
134 struct iovec iov[2];
135 struct ypbind_resp ybr;
136 u_short ypb_port;
137 struct ypbind_binding *bn;
138
139 iov[0].iov_base = (caddr_t) & ypb_port;
140 iov[0].iov_len = sizeof ypb_port;
141 iov[1].iov_base = (caddr_t) & ybr;
142 iov[1].iov_len = sizeof ybr;
143
144 r = readv(fd, iov, 2);
145 if (r != iov[0].iov_len + iov[1].iov_len) {
146 (void)close(fd);
147 ysd->dom_vers = -1;
148 goto again;
149 }
150 (void)memset(&ysd->dom_server_addr, 0,
151 sizeof ysd->dom_server_addr);
152 ysd->dom_server_addr.sin_len =
153 sizeof(struct sockaddr_in);
154 ysd->dom_server_addr.sin_family = AF_INET;
155 bn = &ybr.ypbind_respbody.ypbind_bindinfo;
156 ysd->dom_server_addr.sin_port =
157 bn->ypbind_binding_port;
158
159 ysd->dom_server_addr.sin_addr =
160 bn->ypbind_binding_addr;
161
162 ysd->dom_server_port = ysd->dom_server_addr.sin_port;
163 (void)close(fd);
164 goto gotit;
165 } else {
166 /* no lock on binding file, YP is dead. */
167 (void)close(fd);
168 if (new)
169 free(ysd);
170 return YPERR_YPBIND;
171 }
172 }
173 trynet:
174 if (ysd->dom_vers == -1 || ysd->dom_vers == 0) {
175 struct ypbind_binding *bn;
176 (void)memset(&clnt_sin, 0, sizeof clnt_sin);
177 clnt_sin.sin_len = sizeof(struct sockaddr_in);
178 clnt_sin.sin_family = AF_INET;
179 clnt_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
180
181 clnt_sock = RPC_ANYSOCK;
182 client = clnttcp_create(&clnt_sin, YPBINDPROG, YPBINDVERS,
183 &clnt_sock, 0, 0);
184 if (client == NULL) {
185 clnt_pcreateerror("clnttcp_create");
186 if (new)
187 free(ysd);
188 return YPERR_YPBIND;
189 }
190 r = clnt_call(client, YPBINDPROC_DOMAIN, xdr_domainname,
191 dom, xdr_ypbind_resp, &ypbr, _yplib_timeout);
192 if (r != RPC_SUCCESS) {
193 if (new == 0 || count)
194 fprintf(stderr,
195 "YP server for domain %s not responding, still trying\n",
196 dom);
197 count++;
198 clnt_destroy(client);
199 ysd->dom_vers = -1;
200 goto again;
201 }
202 clnt_destroy(client);
203
204 (void)memset(&ysd->dom_server_addr, 0,
205 sizeof ysd->dom_server_addr);
206 ysd->dom_server_addr.sin_len = sizeof(struct sockaddr_in);
207 ysd->dom_server_addr.sin_family = AF_INET;
208 bn = &ypbr.ypbind_respbody.ypbind_bindinfo;
209 ysd->dom_server_addr.sin_port =
210 bn->ypbind_binding_port;
211 ysd->dom_server_addr.sin_addr.s_addr =
212 bn->ypbind_binding_addr.s_addr;
213 ysd->dom_server_port =
214 bn->ypbind_binding_port;
215 gotit:
216 ysd->dom_vers = YPVERS;
217 (void)strcpy(ysd->dom_domain, dom);
218 }
219 if (ysd->dom_client)
220 clnt_destroy(ysd->dom_client);
221 ysd->dom_socket = RPC_ANYSOCK;
222 ysd->dom_client = clntudp_create(&ysd->dom_server_addr,
223 YPPROG, YPVERS, _yplib_timeout,
224 &ysd->dom_socket);
225 if (ysd->dom_client == NULL) {
226 clnt_pcreateerror("clntudp_create");
227 ysd->dom_vers = -1;
228 goto again;
229 }
230 if (fcntl(ysd->dom_socket, F_SETFD, 1) == -1)
231 perror("fcntl: F_SETFD");
232
233 if (new) {
234 ysd->dom_pnext = _ypbindlist;
235 _ypbindlist = ysd;
236 }
237 if (ypdb != NULL)
238 *ypdb = ysd;
239 return 0;
240 }
241
242 void
243 _yp_unbind(ypb)
244 struct dom_binding *ypb;
245 {
246 clnt_destroy(ypb->dom_client);
247 ypb->dom_client = NULL;
248 ypb->dom_socket = -1;
249 }
250
251 int
252 yp_bind(dom)
253 const char *dom;
254 {
255 return _yp_dobind(dom, NULL);
256 }
257
258 void
259 yp_unbind(dom)
260 const char *dom;
261 {
262 struct dom_binding *ypb, *ypbp;
263
264 ypbp = NULL;
265 for (ypb = _ypbindlist; ypb; ypb = ypb->dom_pnext) {
266 if (strcmp(dom, ypb->dom_domain) == 0) {
267 clnt_destroy(ypb->dom_client);
268 if (ypbp)
269 ypbp->dom_pnext = ypb->dom_pnext;
270 else
271 _ypbindlist = ypb->dom_pnext;
272 free(ypb);
273 return;
274 }
275 ypbp = ypb;
276 }
277 return;
278 }
279
280 int
281 yp_get_default_domain(domp)
282 char **domp;
283 {
284 *domp = NULL;
285 if (_yp_domain[0] == '\0')
286 if (getdomainname(_yp_domain, sizeof _yp_domain))
287 return YPERR_NODOM;
288 *domp = _yp_domain;
289 return 0;
290 }
291
292 int
293 _yp_check(dom)
294 char **dom;
295 {
296 char *unused;
297
298 if (_yp_domain[0] == '\0')
299 if (yp_get_default_domain(&unused))
300 return 0;
301
302 if (dom)
303 *dom = _yp_domain;
304
305 if (yp_bind(_yp_domain) == 0)
306 return 1;
307 return 0;
308 }
309