Remove some unnecessary casts.
[dragonfly.git] / libexec / talkd / process.c
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1/*
2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY 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.
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32 *
33 * @(#)process.c 8.2 (Berkeley) 11/16/93
34 * $FreeBSD: src/libexec/talkd/process.c,v 1.9 1999/08/28 00:10:16 peter Exp $
3eefb696 35 * $DragonFly: src/libexec/talkd/process.c,v 1.3 2003/11/14 03:54:31 dillon Exp $
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36 */
37
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38/*
39 * process.c handles the requests, which can be of three types:
40 * ANNOUNCE - announce to a user that a talk is wanted
41 * LEAVE_INVITE - insert the request into the table
42 * LOOK_UP - look up to see if a request is waiting in
43 * in the table for the local user
44 * DELETE - delete invitation
45 */
46#include <sys/param.h>
47#include <sys/stat.h>
48#include <sys/socket.h>
49#include <netinet/in.h>
50#include <protocols/talkd.h>
51#include <ctype.h>
52#include <err.h>
53#include <netdb.h>
54#include <paths.h>
55#include <stdio.h>
56#include <string.h>
57#include <syslog.h>
58
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59int announce (CTL_MSG *, char *);
60int delete_invite (int);
61void do_announce (CTL_MSG *, CTL_RESPONSE *);
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62CTL_MSG *find_request();
63CTL_MSG *find_match();
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64int find_user (char *, char *);
65void insert_table (CTL_MSG *, CTL_RESPONSE *);
66int new_id (void);
67void print_request (char *, CTL_MSG *);
68void print_response (char *, CTL_RESPONSE *);
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69
70void
71process_request(mp, rp)
72 register CTL_MSG *mp;
73 register CTL_RESPONSE *rp;
74{
75 register CTL_MSG *ptr;
76 extern int debug;
77 char *s;
78
79 rp->vers = TALK_VERSION;
80 rp->type = mp->type;
81 rp->id_num = htonl(0);
82 if (mp->vers != TALK_VERSION) {
83 syslog(LOG_WARNING, "bad protocol version %d", mp->vers);
84 rp->answer = BADVERSION;
85 return;
86 }
87 mp->id_num = ntohl(mp->id_num);
88 mp->addr.sa_family = ntohs(mp->addr.sa_family);
89 if (mp->addr.sa_family != AF_INET) {
90 syslog(LOG_WARNING, "bad address, family %d",
91 mp->addr.sa_family);
92 rp->answer = BADADDR;
93 return;
94 }
95 mp->ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
96 if (mp->ctl_addr.sa_family != AF_INET) {
97 syslog(LOG_WARNING, "bad control address, family %d",
98 mp->ctl_addr.sa_family);
99 rp->answer = BADCTLADDR;
100 return;
101 }
102 for (s = mp->l_name; *s; s++)
103 if (!isprint(*s)) {
104 syslog(LOG_NOTICE, "illegal user name. Aborting");
105 rp->answer = FAILED;
106 return;
107 }
108 mp->pid = ntohl(mp->pid);
109 if (debug)
110 print_request("process_request", mp);
111 switch (mp->type) {
112
113 case ANNOUNCE:
114 do_announce(mp, rp);
115 break;
116
117 case LEAVE_INVITE:
118 ptr = find_request(mp);
119 if (ptr != (CTL_MSG *)0) {
120 rp->id_num = htonl(ptr->id_num);
121 rp->answer = SUCCESS;
122 } else
123 insert_table(mp, rp);
124 break;
125
126 case LOOK_UP:
127 ptr = find_match(mp);
128 if (ptr != (CTL_MSG *)0) {
129 rp->id_num = htonl(ptr->id_num);
130 rp->addr = ptr->addr;
131 rp->addr.sa_family = htons(ptr->addr.sa_family);
132 rp->answer = SUCCESS;
133 } else
134 rp->answer = NOT_HERE;
135 break;
136
137 case DELETE:
138 rp->answer = delete_invite(mp->id_num);
139 break;
140
141 default:
142 rp->answer = UNKNOWN_REQUEST;
143 break;
144 }
145 if (debug)
146 print_response("process_request", rp);
147}
148
149void
150do_announce(mp, rp)
151 register CTL_MSG *mp;
152 CTL_RESPONSE *rp;
153{
154 struct hostent *hp;
155 CTL_MSG *ptr;
156 int result;
157
158 /* see if the user is logged */
159 result = find_user(mp->r_name, mp->r_tty);
160 if (result != SUCCESS) {
161 rp->answer = result;
162 return;
163 }
164#define satosin(sa) ((struct sockaddr_in *)(sa))
15b85273 165 hp = gethostbyaddr(&satosin(&mp->ctl_addr)->sin_addr,
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166 sizeof (struct in_addr), AF_INET);
167 if (hp == (struct hostent *)0) {
168 rp->answer = MACHINE_UNKNOWN;
169 return;
170 }
171 ptr = find_request(mp);
172 if (ptr == (CTL_MSG *) 0) {
173 insert_table(mp, rp);
174 rp->answer = announce(mp, hp->h_name);
175 return;
176 }
177 if (mp->id_num > ptr->id_num) {
178 /*
179 * This is an explicit re-announce, so update the id_num
180 * field to avoid duplicates and re-announce the talk.
181 */
182 ptr->id_num = new_id();
183 rp->id_num = htonl(ptr->id_num);
184 rp->answer = announce(mp, hp->h_name);
185 } else {
186 /* a duplicated request, so ignore it */
187 rp->id_num = htonl(ptr->id_num);
188 rp->answer = SUCCESS;
189 }
190}
191
192#include <utmp.h>
193
194/*
195 * Search utmp for the local user
196 */
197int
198find_user(name, tty)
199 char *name, *tty;
200{
201 struct utmp ubuf;
202 int status;
203 FILE *fd;
204 struct stat statb;
205 time_t best = 0;
206 char line[sizeof(ubuf.ut_line) + 1];
207 char ftty[sizeof(_PATH_DEV) - 1 + sizeof(line)];
208
209 if ((fd = fopen(_PATH_UTMP, "r")) == NULL) {
210 warnx("can't read %s", _PATH_UTMP);
211 return (FAILED);
212 }
213#define SCMPN(a, b) strncmp(a, b, sizeof (a))
214 status = NOT_HERE;
215 (void) strcpy(ftty, _PATH_DEV);
216 while (fread((char *) &ubuf, sizeof ubuf, 1, fd) == 1)
217 if (SCMPN(ubuf.ut_name, name) == 0) {
218 strncpy(line, ubuf.ut_line, sizeof(ubuf.ut_line));
219 line[sizeof(ubuf.ut_line)] = '\0';
220 if (*tty == '\0' || best != 0) {
221 if (best == 0)
222 status = PERMISSION_DENIED;
223 /* no particular tty was requested */
224 (void) strcpy(ftty + sizeof(_PATH_DEV) - 1,
225 line);
226 if (stat(ftty, &statb) == 0) {
227 if (!(statb.st_mode & 020))
228 continue;
229 if (statb.st_atime > best) {
230 best = statb.st_atime;
231 (void) strcpy(tty, line);
232 status = SUCCESS;
233 continue;
234 }
235 }
236 }
237 if (strcmp(line, tty) == 0) {
238 status = SUCCESS;
239 break;
240 }
241 }
242 fclose(fd);
243 return (status);
244}