1/*
2 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
7 * Reserved.  This file contains Original Code and/or Modifications of
8 * Original Code as defined in and that are subject to the Apple Public
9 * Source License Version 1.1 (the "License").  You may not use this file
10 * except in compliance with the License.  Please obtain a copy of the
11 * License at http://www.apple.com/publicsource and read it before using
12 * this file.
13 *
14 * The Original Code and all software distributed under the License are
15 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
16 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
17 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
19 * License for the specific language governing rights and limitations
20 * under the License.
21 *
22 * @APPLE_LICENSE_HEADER_END@
23 */
24/*
25 * Copyright (c) 1996 Theo de Raadt <deraadt@theos.com>
26 * Copyright (c) 1992, 1993 Theo de Raadt <deraadt@theos.com>
27 * All rights reserved.
28 *
29 * Redistribution and use in source and binary forms, with or without
30 * modification, are permitted provided that the following conditions
31 * are met:
32 * 1. Redistributions of source code must retain the above copyright
33 *    notice, this list of conditions and the following disclaimer.
34 * 2. Redistributions in binary form must reproduce the above copyright
35 *    notice, this list of conditions and the following disclaimer in the
36 *    documentation and/or other materials provided with the distribution.
37 * 3. All advertising materials mentioning features or use of this software
38 *    must display the following acknowledgement:
39 *	This product includes software developed by Theo de Raadt.
40 * 4. The name of the author may not be used to endorse or promote products
41 *    derived from this software without specific prior written permission.
42 *
43 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
44 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
45 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
47 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * SUCH DAMAGE.
54 */
55
56#if defined(LIBC_SCCS) && !defined(lint)
57static char *rcsid = "$OpenBSD: yp_bind.c,v 1.9 1997/04/29 21:25:20 deraadt Exp $";
58#endif /* LIBC_SCCS and not lint */
59
60#include <sys/param.h>
61#include <sys/types.h>
62#include <sys/socket.h>
63#include <sys/file.h>
64#include <sys/uio.h>
65#include <errno.h>
66#include <stdio.h>
67#include <stdlib.h>
68#include <string.h>
69#include <unistd.h>
70#include <rpc/rpc.h>
71#include <rpc/xdr.h>
72#include <rpcsvc/yp.h>
73#include <rpcsvc/ypclnt.h>
74#include <notify.h>
75#include <pthread.h>
76#include "ypinternal.h"
77
78extern int notify_register_plain(char *, int *);
79
80struct dom_binding *_ypbindlist = NULL;
81char _yp_domain[MAXHOSTNAMELEN] = { '\0' };
82
83int _yplib_timeout = 10;
84
85int
86_yp_dobind(dom, ypdb)
87	const char     *dom;
88	struct dom_binding **ypdb;
89{
90	static int      pid = -1;
91	struct dom_binding *ysd, *ysd2;
92	struct ypbind_resp ypbr;
93	struct timeval  tv;
94	struct sockaddr_in clnt_sin;
95	struct ypbind_binding *bn;
96	int             clnt_sock, fd, gpid;
97	CLIENT         *client;
98	int             new = 0, r, proto;
99	int             count = 0;
100	u_short		port;
101	int status, notify_token;
102	uint64_t abort;
103	char *notify_name;
104
105	/*
106	 * test if YP is running or not
107	 */
108	if ((fd = open(YPBINDLOCK, O_RDONLY)) == -1) return YPERR_YPBIND;
109
110	if (!((flock(fd, LOCK_EX | LOCK_NB) == -1) && (errno == EWOULDBLOCK)))
111	{
112		close(fd);
113		return YPERR_YPBIND;
114	}
115
116	close(fd);
117
118	gpid = getpid();
119	if (!((pid == -1) || (pid == gpid)))
120	{
121		ysd = _ypbindlist;
122		while (ysd)
123		{
124			if (ysd->dom_client) clnt_destroy(ysd->dom_client);
125			ysd2 = ysd->dom_pnext;
126			free(ysd);
127			ysd = ysd2;
128		}
129
130		_ypbindlist = NULL;
131	}
132
133	pid = gpid;
134
135	if (ypdb != NULL) *ypdb = NULL;
136
137	if ((dom == NULL) || (strlen(dom) == 0)) return YPERR_BADARGS;
138
139	for (ysd = _ypbindlist; ysd; ysd = ysd->dom_pnext)
140	{
141		if (strcmp(dom, ysd->dom_domain) == 0) break;
142	}
143
144	if (ysd == NULL)
145	{
146		ysd = calloc(1, sizeof(struct dom_binding));
147		if (ysd == NULL) return YPERR_YPERR;
148		ysd->dom_socket = -1;
149		ysd->dom_vers = 0;
150		new = 1;
151	}
152
153	/*
154	 * Get notification token
155	 * we use a self-notification token to allow a caller
156	 * to signal the thread doing this bind call to quit.
157	 */
158	notify_name = NULL;
159	notify_token = -1;
160
161	asprintf(&notify_name, "self.thread.%lu", (unsigned long)pthread_self());
162	if (notify_name != NULL)
163	{
164		status = notify_register_plain(notify_name, &notify_token);
165		free(notify_name);
166	}
167
168again:
169	if (notify_token != -1)
170	{
171		abort = 0;
172		status = notify_get_state(notify_token, &abort);
173		if (abort == ThreadStateExitRequested)
174		{
175			if (new) free(ysd);
176			notify_cancel(notify_token);
177			return YPERR_YPBIND;
178		}
179	}
180
181	proto = YP_BIND_UDP;
182	if (ysd->dom_vers == YP_BIND_TCP) proto = YP_BIND_TCP;
183
184	if ((ysd->dom_vers == 0) || (ysd->dom_vers == YP_BIND_UDP) || (ysd->dom_vers == YP_BIND_TCP))
185	{
186		memset(&clnt_sin, 0, sizeof clnt_sin);
187		clnt_sin.sin_len = sizeof(struct sockaddr_in);
188		clnt_sin.sin_family = AF_INET;
189		clnt_sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
190
191		clnt_sock = RPC_ANYSOCK;
192		client = clnttcp_create(&clnt_sin, YPBINDPROG, YPBINDVERS, &clnt_sock, 0, 0);
193		if (client == NULL)
194		{
195			clnt_pcreateerror("clnttcp_create");
196			if (new) free(ysd);
197			if (notify_token != -1) notify_cancel(notify_token);
198			return YPERR_YPBIND;
199		}
200
201		if ((ntohs(clnt_sin.sin_port) >= IPPORT_RESERVED) || (ntohs(clnt_sin.sin_port) == 20))
202		{
203			/*
204			 * YP was not running, but someone has registered
205			 * ypbind with portmap -- this simply means YP is
206			 * not running.
207			 */
208			clnt_destroy(client);
209			if (new) free(ysd);
210			if (notify_token != -1) notify_cancel(notify_token);
211			return YPERR_YPBIND;
212		}
213
214		tv.tv_sec = _yplib_timeout;
215		tv.tv_usec = 0;
216
217		r = clnt_call(client, YPBINDPROC_DOMAIN, (xdrproc_t)xdr_domainname, &dom, (xdrproc_t)xdr_ypbind_resp, &ypbr, tv);
218		if (r != RPC_SUCCESS)
219		{
220			if (new == 0 || count) fprintf(stderr, "YP server for domain %s not responding, still trying\n", dom);
221			count++;
222			clnt_destroy(client);
223			ysd->dom_vers = proto;
224			goto again;
225		}
226
227		clnt_destroy(client);
228
229		bn = &ypbr.ypbind_resp_u.ypbind_bindinfo;
230		memcpy(&port, &bn->ypbind_binding_port, sizeof port);
231		if ((ntohs(port) >= IPPORT_RESERVED) || (ntohs(port) == 20))
232		{
233			/*
234			 * This is bogus -- the ypbind wants me to
235			 * communicate to an insecure ypserv.  We are
236			 * within rights to syslog this as an attack,
237			 * but for now we'll simply ignore it; real YP
238			 * is obviously not running.
239			 */
240			if (new) free(ysd);
241			if (notify_token != -1) notify_cancel(notify_token);
242			return YPERR_YPBIND;
243		}
244
245		memset(&ysd->dom_server_addr, 0,  sizeof ysd->dom_server_addr);
246		ysd->dom_server_addr.sin_len = sizeof(struct sockaddr_in);
247		ysd->dom_server_addr.sin_family = AF_INET;
248		memcpy(&ysd->dom_server_addr.sin_port, &bn->ypbind_binding_port, sizeof(ysd->dom_server_addr.sin_port));
249		memcpy(&ysd->dom_server_addr.sin_addr.s_addr, &bn->ypbind_binding_addr, sizeof(ysd->dom_server_addr.sin_addr.s_addr));
250		ysd->dom_server_port = ysd->dom_server_addr.sin_port;
251		ysd->dom_vers = YPVERS;
252		strncpy(ysd->dom_domain, dom, sizeof ysd->dom_domain-1);
253		ysd->dom_domain[sizeof ysd->dom_domain-1] = '\0';
254	}
255
256	tv.tv_sec = _yplib_timeout / 2;
257	tv.tv_usec = 0;
258
259	if (ysd->dom_client) clnt_destroy(ysd->dom_client);
260	ysd->dom_socket = RPC_ANYSOCK;
261
262	if (proto == YP_BIND_UDP) ysd->dom_client = clntudp_create(&ysd->dom_server_addr, YPPROG, YPVERS, tv, &ysd->dom_socket);
263	else ysd->dom_client = clnttcp_create(&ysd->dom_server_addr, YPPROG, YPVERS, &ysd->dom_socket, 0, 0);
264
265	if (ysd->dom_client == NULL)
266	{
267		if (proto == YP_BIND_UDP) clnt_pcreateerror("clntudp_create");
268		else clnt_pcreateerror("clnttcp_create");
269		ysd->dom_vers = proto;
270		goto again;
271	}
272
273	if (notify_token != -1) notify_cancel(notify_token);
274
275	if (fcntl(ysd->dom_socket, F_SETFD, 1) == -1)
276		perror("fcntl: F_SETFD");
277
278	if (new != 0)
279	{
280		ysd->dom_pnext = _ypbindlist;
281		_ypbindlist = ysd;
282	}
283
284	if (ypdb != NULL) *ypdb = ysd;
285	return 0;
286}
287
288void
289_yp_unbind(ypb)
290	struct dom_binding *ypb;
291{
292	if (ypb->dom_client) clnt_destroy(ypb->dom_client);
293	ypb->dom_client = NULL;
294	ypb->dom_socket = -1;
295}
296
297int
298yp_bind(dom)
299	const char     *dom;
300{
301	return _yp_dobind(dom, NULL);
302}
303
304void
305yp_unbind(dom)
306	const char     *dom;
307{
308	struct dom_binding *ypb, *ypbp;
309
310	ypbp = NULL;
311	for (ypb = _ypbindlist; ypb; ypb = ypb->dom_pnext) {
312		if (strcmp(dom, ypb->dom_domain) == 0) {
313			if (ypb->dom_client) clnt_destroy(ypb->dom_client);
314			if (ypbp)
315				ypbp->dom_pnext = ypb->dom_pnext;
316			else
317				_ypbindlist = ypb->dom_pnext;
318			free(ypb);
319			return;
320		}
321		ypbp = ypb;
322	}
323}
324