[apple/network_cmds.git] / talkd.tproj / process.c

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1983, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)process.c	8.2 (Berkeley) 11/16/93";
#endif /* not lint */

/*
 * process.c handles the requests, which can be of three types:
 *	ANNOUNCE - announce to a user that a talk is wanted
 *	LEAVE_INVITE - insert the request into the table
 *	LOOK_UP - look up to see if a request is waiting in
 *		  in the table for the local user
 *	DELETE - delete invitation
 */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <protocols/talkd.h>
#include <netdb.h>
#include <syslog.h>
#include <stdio.h>
#include <string.h>
#include <paths.h>
#include "talkd.h"

CTL_MSG *find_request();
CTL_MSG *find_match();

void
process_request(mp, rp)
	register CTL_MSG *mp;
	register CTL_RESPONSE *rp;
{
	register CTL_MSG *ptr;
	extern int debug;

	rp->vers = TALK_VERSION;
	rp->type = mp->type;
	rp->id_num = htonl(0);
	if (mp->vers != TALK_VERSION) {
		syslog(LOG_WARNING, "Bad protocol version %d", mp->vers);
		rp->answer = BADVERSION;
		return;
	}
	mp->id_num = ntohl(mp->id_num);
	mp->addr.sa_family = ntohs(mp->addr.sa_family);
	if (mp->addr.sa_family != AF_INET) {
		syslog(LOG_WARNING, "Bad address, family %d",
		    mp->addr.sa_family);
		rp->answer = BADADDR;
		return;
	}
	mp->ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
	if (mp->ctl_addr.sa_family != AF_INET) {
		syslog(LOG_WARNING, "Bad control address, family %d",
		    mp->ctl_addr.sa_family);
		rp->answer = BADCTLADDR;
		return;
	}
	mp->pid = ntohl(mp->pid);
	if (debug)
		print_request("process_request", mp);
	switch (mp->type) {

	case ANNOUNCE:
		do_announce(mp, rp);
		break;

	case LEAVE_INVITE:
		ptr = find_request(mp);
		if (ptr != (CTL_MSG *)0) {
			rp->id_num = htonl(ptr->id_num);
			rp->answer = SUCCESS;
		} else
			insert_table(mp, rp);
		break;

	case LOOK_UP:
		ptr = find_match(mp);
		if (ptr != (CTL_MSG *)0) {
			rp->id_num = htonl(ptr->id_num);
			rp->addr = ptr->addr;
			rp->addr.sa_family = htons(ptr->addr.sa_family);
			rp->answer = SUCCESS;
		} else
			rp->answer = NOT_HERE;
		break;

	case DELETE:
		rp->answer = delete_invite(mp->id_num);
		break;

	default:
		rp->answer = UNKNOWN_REQUEST;
		break;
	}
	if (debug)
		print_response("process_request", rp);
}

void
do_announce(mp, rp)
	register CTL_MSG *mp;
	CTL_RESPONSE *rp;
{
	struct hostent *hp;
	CTL_MSG *ptr;
	int result;

	/* see if the user is logged */
	result = find_user(mp->r_name, mp->r_tty);
	if (result != SUCCESS) {
		rp->answer = result;
		return;
	}
#define	satosin(sa)	((struct sockaddr_in *)(sa))
	hp = gethostbyaddr((char *)&satosin(&mp->ctl_addr)->sin_addr,
		sizeof (struct in_addr), AF_INET);
	if (hp == (struct hostent *)0) {
		rp->answer = MACHINE_UNKNOWN;
		return;
	}
	ptr = find_request(mp);
	if (ptr == (CTL_MSG *) 0) {
		insert_table(mp, rp);
		rp->answer = announce(mp, hp->h_name);
		return;
	}
	if (mp->id_num > ptr->id_num) {
		/*
		 * This is an explicit re-announce, so update the id_num
		 * field to avoid duplicates and re-announce the talk.
		 */
		ptr->id_num = new_id();
		rp->id_num = htonl(ptr->id_num);
		rp->answer = announce(mp, hp->h_name);
	} else {
		/* a duplicated request, so ignore it */
		rp->id_num = htonl(ptr->id_num);
		rp->answer = SUCCESS;
	}
}

#include <utmp.h>

/*
 * Search utmp for the local user
 */
int
find_user(name, tty)
	char *name, *tty;
{
	struct utmp ubuf;
	int status;
	FILE *fd;
	struct stat statb;
	char line[sizeof(ubuf.ut_line) + 1];
	char ftty[sizeof(_PATH_DEV) - 1 + sizeof(line)];

	if ((fd = fopen(_PATH_UTMP, "r")) == NULL) {
		fprintf(stderr, "talkd: can't read %s.\n", _PATH_UTMP);
		return (FAILED);
	}
#define SCMPN(a, b)	strncmp(a, b, sizeof (a))
	status = NOT_HERE;
	(void) strcpy(ftty, _PATH_DEV);
	while (fread((char *) &ubuf, sizeof ubuf, 1, fd) == 1)
		if (SCMPN(ubuf.ut_name, name) == 0) {
			strncpy(line, ubuf.ut_line, sizeof(ubuf.ut_line));
			line[sizeof(ubuf.ut_line)] = '\0';
			if (*tty == '\0') {
				status = PERMISSION_DENIED;
				/* no particular tty was requested */
				(void) strcpy(ftty + sizeof(_PATH_DEV) - 1,
				    line);
				if (stat(ftty, &statb) == 0) {
					if (!(statb.st_mode & 020))
						continue;
					(void) strcpy(tty, line);
					status = SUCCESS;
					break;
				}
			}
			if (strcmp(line, tty) == 0) {
				status = SUCCESS;
				break;
			}
		}
	fclose(fd);
	return (status);
}
Commit	Line	Data
b7080c8e A	1	/*
	2	* Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
ffda1f4a A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
b7080c8e A	12	*
	13	* The Original Code and all software distributed under the License are
	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
ffda1f4a A	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
b7080c8e A	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23	/*
	24	* Copyright (c) 1983, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	*
	27	* Redistribution and use in source and binary forms, with or without
	28	* modification, are permitted provided that the following conditions
	29	* are met:
	30	* 1. Redistributions of source code must retain the above copyright
	31	* notice, this list of conditions and the following disclaimer.
	32	* 2. Redistributions in binary form must reproduce the above copyright
	33	* notice, this list of conditions and the following disclaimer in the
	34	* documentation and/or other materials provided with the distribution.
	35	* 3. All advertising materials mentioning features or use of this software
	36	* must display the following acknowledgement:
	37	* This product includes software developed by the University of
	38	* California, Berkeley and its contributors.
	39	* 4. Neither the name of the University nor the names of its contributors
	40	* may be used to endorse or promote products derived from this software
	41	* without specific prior written permission.
	42	*
	43	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	44	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	45	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	46	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	47	* FOR ANY 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	#ifndef lint
	57	static char sccsid[] = "@(#)process.c 8.2 (Berkeley) 11/16/93";
	58	#endif /* not lint */
	59
	60	/*
	61	* process.c handles the requests, which can be of three types:
	62	* ANNOUNCE - announce to a user that a talk is wanted
	63	* LEAVE_INVITE - insert the request into the table
	64	* LOOK_UP - look up to see if a request is waiting in
	65	* in the table for the local user
	66	* DELETE - delete invitation
	67	*/
	68	#include <sys/param.h>
	69	#include <sys/stat.h>
	70	#include <sys/socket.h>
	71	#include <netinet/in.h>
	72	#include <protocols/talkd.h>
	73	#include <netdb.h>
	74	#include <syslog.h>
	75	#include <stdio.h>
	76	#include <string.h>
	77	#include <paths.h>
	78	#include "talkd.h"
	79
	80	CTL_MSG *find_request();
	81	CTL_MSG *find_match();
	82
	83	void
84	process_request(mp, rp)
85	register CTL_MSG *mp;
86	register CTL_RESPONSE *rp;
87	{
88	register CTL_MSG *ptr;
89	extern int debug;
90
91	rp->vers = TALK_VERSION;
92	rp->type = mp->type;
93	rp->id_num = htonl(0);
94	if (mp->vers != TALK_VERSION) {
95	syslog(LOG_WARNING, "Bad protocol version %d", mp->vers);
96	rp->answer = BADVERSION;
97	return;
98	}
99	mp->id_num = ntohl(mp->id_num);
100	mp->addr.sa_family = ntohs(mp->addr.sa_family);
101	if (mp->addr.sa_family != AF_INET) {
102	syslog(LOG_WARNING, "Bad address, family %d",
103	mp->addr.sa_family);
104	rp->answer = BADADDR;
105	return;
106	}
107	mp->ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
108	if (mp->ctl_addr.sa_family != AF_INET) {
109	syslog(LOG_WARNING, "Bad control address, family %d",
110	mp->ctl_addr.sa_family);
111	rp->answer = BADCTLADDR;
112	return;
113	}
114	mp->pid = ntohl(mp->pid);
115	if (debug)
116	print_request("process_request", mp);
117	switch (mp->type) {
118
119	case ANNOUNCE:
120	do_announce(mp, rp);
121	break;
122
123	case LEAVE_INVITE:
124	ptr = find_request(mp);
125	if (ptr != (CTL_MSG *)0) {
126	rp->id_num = htonl(ptr->id_num);
127	rp->answer = SUCCESS;
128	} else
129	insert_table(mp, rp);
130	break;
131
132	case LOOK_UP:
133	ptr = find_match(mp);
134	if (ptr != (CTL_MSG *)0) {
135	rp->id_num = htonl(ptr->id_num);
136	rp->addr = ptr->addr;
137	rp->addr.sa_family = htons(ptr->addr.sa_family);
138	rp->answer = SUCCESS;
139	} else
140	rp->answer = NOT_HERE;
141	break;
142
143	case DELETE:
144	rp->answer = delete_invite(mp->id_num);
145	break;
146
147	default:
148	rp->answer = UNKNOWN_REQUEST;
149	break;
150	}
151	if (debug)
152	print_response("process_request", rp);
153	}
154
155	void
156	do_announce(mp, rp)
157	register CTL_MSG *mp;
158	CTL_RESPONSE *rp;
159	{
160	struct hostent *hp;
161	CTL_MSG *ptr;
162	int result;
163
164	/* see if the user is logged */
165	result = find_user(mp->r_name, mp->r_tty);
166	if (result != SUCCESS) {
167	rp->answer = result;
168	return;
169	}
170	#define satosin(sa) ((struct sockaddr_in *)(sa))
171	hp = gethostbyaddr((char *)&satosin(&mp->ctl_addr)->sin_addr,
172	sizeof (struct in_addr), AF_INET);
173	if (hp == (struct hostent *)0) {
174	rp->answer = MACHINE_UNKNOWN;
175	return;
176	}
177	ptr = find_request(mp);
178	if (ptr == (CTL_MSG *) 0) {
179	insert_table(mp, rp);
180	rp->answer = announce(mp, hp->h_name);
181	return;
182	}
183	if (mp->id_num > ptr->id_num) {
184	/*
185	* This is an explicit re-announce, so update the id_num
186	* field to avoid duplicates and re-announce the talk.
187	*/
188	ptr->id_num = new_id();
189	rp->id_num = htonl(ptr->id_num);
190	rp->answer = announce(mp, hp->h_name);
191	} else {
192	/* a duplicated request, so ignore it */
193	rp->id_num = htonl(ptr->id_num);
194	rp->answer = SUCCESS;
195	}
196	}
197
198	#include <utmp.h>
199
200	/*
201	* Search utmp for the local user
202	*/
203	int
204	find_user(name, tty)
205	char name, tty;
206	{
207	struct utmp ubuf;
208	int status;
209	FILE *fd;
210	struct stat statb;
211	char line[sizeof(ubuf.ut_line) + 1];
212	char ftty[sizeof(_PATH_DEV) - 1 + sizeof(line)];
213
214	if ((fd = fopen(_PATH_UTMP, "r")) == NULL) {
215	fprintf(stderr, "talkd: can't read %s.\n", _PATH_UTMP);
216	return (FAILED);
217	}
218	#define SCMPN(a, b) strncmp(a, b, sizeof (a))
219	status = NOT_HERE;
220	(void) strcpy(ftty, _PATH_DEV);
221	while (fread((char *) &ubuf, sizeof ubuf, 1, fd) == 1)
222	if (SCMPN(ubuf.ut_name, name) == 0) {
223	strncpy(line, ubuf.ut_line, sizeof(ubuf.ut_line));
224	line[sizeof(ubuf.ut_line)] = '\0';
225	if (*tty == '\0') {
226	status = PERMISSION_DENIED;
227	/* no particular tty was requested */
228	(void) strcpy(ftty + sizeof(_PATH_DEV) - 1,
229	line);
230	if (stat(ftty, &statb) == 0) {
231	if (!(statb.st_mode & 020))
232	continue;
233	(void) strcpy(tty, line);
234	status = SUCCESS;
235	break;
236	}
237	}
238	if (strcmp(line, tty) == 0) {
239	status = SUCCESS;
240	break;
241	}
242	}
243	fclose(fd);
244	return (status);
245	}