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

/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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	*
ac2f15b3 A	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
	7	*
	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
b7080c8e A	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
ac2f15b3 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
b7080c8e A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* Copyright (c) 1983, 1993
	27	* The Regents of the University of California. 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 the University of
	40	* California, Berkeley and its contributors.
	41	* 4. Neither the name of the University nor the names of its contributors
	42	* may be used to endorse or promote products derived from this software
	43	* without specific prior written permission.
	44	*
	45	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	46	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	47	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	48	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	49	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	50	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	51	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	52	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	53	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	54	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	55	* SUCH DAMAGE.
	56	*/
	57
	58	#ifndef lint
	59	static char sccsid[] = "@(#)process.c 8.2 (Berkeley) 11/16/93";
	60	#endif /* not lint */
	61
	62	/*
	63	* process.c handles the requests, which can be of three types:
	64	* ANNOUNCE - announce to a user that a talk is wanted
	65	* LEAVE_INVITE - insert the request into the table
	66	* LOOK_UP - look up to see if a request is waiting in
	67	* in the table for the local user
	68	* DELETE - delete invitation
	69	*/
	70	#include <sys/param.h>
	71	#include <sys/stat.h>
	72	#include <sys/socket.h>
	73	#include <netinet/in.h>
	74	#include <protocols/talkd.h>
	75	#include <netdb.h>
	76	#include <syslog.h>
	77	#include <stdio.h>
	78	#include <string.h>
	79	#include <paths.h>
	80	#include "talkd.h"
	81
	82	CTL_MSG *find_request();
	83	CTL_MSG *find_match();
	84
	85	void
86	process_request(mp, rp)
87	register CTL_MSG *mp;
88	register CTL_RESPONSE *rp;
89	{
90	register CTL_MSG *ptr;
91	extern int debug;
92
93	rp->vers = TALK_VERSION;
94	rp->type = mp->type;
95	rp->id_num = htonl(0);
96	if (mp->vers != TALK_VERSION) {
97	syslog(LOG_WARNING, "Bad protocol version %d", mp->vers);
98	rp->answer = BADVERSION;
99	return;
100	}
101	mp->id_num = ntohl(mp->id_num);
102	mp->addr.sa_family = ntohs(mp->addr.sa_family);
103	if (mp->addr.sa_family != AF_INET) {
104	syslog(LOG_WARNING, "Bad address, family %d",
105	mp->addr.sa_family);
106	rp->answer = BADADDR;
107	return;
108	}
109	mp->ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
110	if (mp->ctl_addr.sa_family != AF_INET) {
111	syslog(LOG_WARNING, "Bad control address, family %d",
112	mp->ctl_addr.sa_family);
113	rp->answer = BADCTLADDR;
114	return;
115	}
116	mp->pid = ntohl(mp->pid);
117	if (debug)
118	print_request("process_request", mp);
119	switch (mp->type) {
120
121	case ANNOUNCE:
122	do_announce(mp, rp);
123	break;
124
125	case LEAVE_INVITE:
126	ptr = find_request(mp);
127	if (ptr != (CTL_MSG *)0) {
128	rp->id_num = htonl(ptr->id_num);
129	rp->answer = SUCCESS;
130	} else
131	insert_table(mp, rp);
132	break;
133
134	case LOOK_UP:
135	ptr = find_match(mp);
136	if (ptr != (CTL_MSG *)0) {
137	rp->id_num = htonl(ptr->id_num);
138	rp->addr = ptr->addr;
139	rp->addr.sa_family = htons(ptr->addr.sa_family);
140	rp->answer = SUCCESS;
141	} else
142	rp->answer = NOT_HERE;
143	break;
144
145	case DELETE:
146	rp->answer = delete_invite(mp->id_num);
147	break;
148
149	default:
150	rp->answer = UNKNOWN_REQUEST;
151	break;
152	}
153	if (debug)
154	print_response("process_request", rp);
155	}
156
157	void
158	do_announce(mp, rp)
159	register CTL_MSG *mp;
160	CTL_RESPONSE *rp;
161	{
162	struct hostent *hp;
163	CTL_MSG *ptr;
164	int result;
165
166	/* see if the user is logged */
167	result = find_user(mp->r_name, mp->r_tty);
168	if (result != SUCCESS) {
169	rp->answer = result;
170	return;
171	}
172	#define satosin(sa) ((struct sockaddr_in *)(sa))
173	hp = gethostbyaddr((char *)&satosin(&mp->ctl_addr)->sin_addr,
174	sizeof (struct in_addr), AF_INET);
175	if (hp == (struct hostent *)0) {
176	rp->answer = MACHINE_UNKNOWN;
177	return;
178	}
179	ptr = find_request(mp);
180	if (ptr == (CTL_MSG *) 0) {
181	insert_table(mp, rp);
182	rp->answer = announce(mp, hp->h_name);
183	return;
184	}
185	if (mp->id_num > ptr->id_num) {
186	/*
187	* This is an explicit re-announce, so update the id_num
188	* field to avoid duplicates and re-announce the talk.
189	*/
190	ptr->id_num = new_id();
191	rp->id_num = htonl(ptr->id_num);
192	rp->answer = announce(mp, hp->h_name);
193	} else {
194	/* a duplicated request, so ignore it */
195	rp->id_num = htonl(ptr->id_num);
196	rp->answer = SUCCESS;
197	}
198	}
199
200	#include <utmp.h>
201
202	/*
203	* Search utmp for the local user
204	*/
205	int
206	find_user(name, tty)
207	char name, tty;
208	{
209	struct utmp ubuf;
210	int status;
211	FILE *fd;
212	struct stat statb;
213	char line[sizeof(ubuf.ut_line) + 1];
214	char ftty[sizeof(_PATH_DEV) - 1 + sizeof(line)];
215
216	if ((fd = fopen(_PATH_UTMP, "r")) == NULL) {
217	fprintf(stderr, "talkd: can't read %s.\n", _PATH_UTMP);
218	return (FAILED);
219	}
220	#define SCMPN(a, b) strncmp(a, b, sizeof (a))
221	status = NOT_HERE;
222	(void) strcpy(ftty, _PATH_DEV);
223	while (fread((char *) &ubuf, sizeof ubuf, 1, fd) == 1)
224	if (SCMPN(ubuf.ut_name, name) == 0) {
225	strncpy(line, ubuf.ut_line, sizeof(ubuf.ut_line));
226	line[sizeof(ubuf.ut_line)] = '\0';
227	if (*tty == '\0') {
228	status = PERMISSION_DENIED;
229	/* no particular tty was requested */
230	(void) strcpy(ftty + sizeof(_PATH_DEV) - 1,
231	line);
232	if (stat(ftty, &statb) == 0) {
233	if (!(statb.st_mode & 020))
234	continue;
235	(void) strcpy(tty, line);
236	status = SUCCESS;
237	break;
238	}
239	}
240	if (strcmp(line, tty) == 0) {
241	status = SUCCESS;
242	break;
243	}
244	}
245	fclose(fd);
246	return (status);
247	}