Upgrade libressl. 1/2
[dragonfly.git] / libexec / talkd / process.c
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)process.c        8.2 (Berkeley) 11/16/93
30  * $FreeBSD: src/libexec/talkd/process.c,v 1.9 1999/08/28 00:10:16 peter Exp $
31  */
32
33 /*
34  * process.c handles the requests, which can be of three types:
35  *      ANNOUNCE - announce to a user that a talk is wanted
36  *      LEAVE_INVITE - insert the request into the table
37  *      LOOK_UP - look up to see if a request is waiting in
38  *                in the table for the local user
39  *      DELETE - delete invitation
40  */
41 #include <sys/param.h>
42 #include <sys/stat.h>
43 #include <sys/socket.h>
44 #include <netinet/in.h>
45 #include <protocols/talkd.h>
46 #include <ctype.h>
47 #include <err.h>
48 #include <netdb.h>
49 #include <paths.h>
50 #include <stdio.h>
51 #include <string.h>
52 #include <syslog.h>
53 #include "utmpentry.h"
54
55 #include "extern.h"
56
57 extern int debug;
58
59 void
60 process_request(CTL_MSG *mp, CTL_RESPONSE *rp)
61 {
62         CTL_MSG *ptr;
63         char *s;
64
65         rp->vers = TALK_VERSION;
66         rp->type = mp->type;
67         rp->id_num = htonl(0);
68         if (mp->vers != TALK_VERSION) {
69                 syslog(LOG_WARNING, "bad protocol version %d", mp->vers);
70                 rp->answer = BADVERSION;
71                 return;
72         }
73         mp->id_num = ntohl(mp->id_num);
74         mp->addr.sa_family = ntohs(mp->addr.sa_family);
75         if (mp->addr.sa_family != AF_INET) {
76                 syslog(LOG_WARNING, "bad address, family %d",
77                     mp->addr.sa_family);
78                 rp->answer = BADADDR;
79                 return;
80         }
81         mp->ctl_addr.sa_family = ntohs(mp->ctl_addr.sa_family);
82         if (mp->ctl_addr.sa_family != AF_INET) {
83                 syslog(LOG_WARNING, "bad control address, family %d",
84                     mp->ctl_addr.sa_family);
85                 rp->answer = BADCTLADDR;
86                 return;
87         }
88         for (s = mp->l_name; *s; s++)
89                 if (!isprint(*s)) {
90                         syslog(LOG_NOTICE, "illegal user name. Aborting");
91                         rp->answer = FAILED;
92                         return;
93                 }
94         mp->pid = ntohl(mp->pid);
95         if (debug)
96                 print_request("process_request", mp);
97         switch (mp->type) {
98
99         case ANNOUNCE:
100                 do_announce(mp, rp);
101                 break;
102
103         case LEAVE_INVITE:
104                 ptr = find_request(mp);
105                 if (ptr != NULL) {
106                         rp->id_num = htonl(ptr->id_num);
107                         rp->answer = SUCCESS;
108                 } else
109                         insert_table(mp, rp);
110                 break;
111
112         case LOOK_UP:
113                 ptr = find_match(mp);
114                 if (ptr != NULL) {
115                         rp->id_num = htonl(ptr->id_num);
116                         rp->addr = ptr->addr;
117                         rp->addr.sa_family = htons(ptr->addr.sa_family);
118                         rp->answer = SUCCESS;
119                 } else
120                         rp->answer = NOT_HERE;
121                 break;
122
123         case DELETE:
124                 rp->answer = delete_invite(mp->id_num);
125                 break;
126
127         default:
128                 rp->answer = UNKNOWN_REQUEST;
129                 break;
130         }
131         if (debug)
132                 print_response("process_request", rp);
133 }
134
135 void
136 do_announce(CTL_MSG *mp, CTL_RESPONSE *rp)
137 {
138         struct hostent *hp;
139         CTL_MSG *ptr;
140         int result;
141
142         /* see if the user is logged */
143         result = find_user(mp->r_name, mp->r_tty);
144         if (result != SUCCESS) {
145                 rp->answer = result;
146                 return;
147         }
148 #define satosin(sa)     ((struct sockaddr_in *)(void *)(sa))
149         hp = gethostbyaddr(&satosin(&mp->ctl_addr)->sin_addr,
150                 sizeof (struct in_addr), AF_INET);
151         if (hp == NULL) {
152                 rp->answer = MACHINE_UNKNOWN;
153                 return;
154         }
155         ptr = find_request(mp);
156         if (ptr == NULL) {
157                 insert_table(mp, rp);
158                 rp->answer = announce(mp, hp->h_name);
159                 return;
160         }
161         if (mp->id_num > ptr->id_num) {
162                 /*
163                  * This is an explicit re-announce, so update the id_num
164                  * field to avoid duplicates and re-announce the talk.
165                  */
166                 ptr->id_num = new_id();
167                 rp->id_num = htonl(ptr->id_num);
168                 rp->answer = announce(mp, hp->h_name);
169         } else {
170                 /* a duplicated request, so ignore it */
171                 rp->id_num = htonl(ptr->id_num);
172                 rp->answer = SUCCESS;
173         }
174 }
175
176 /*
177  * Search utmpx for the local user
178  */
179 int
180 find_user(const char *name, char *tty)
181 {
182         struct utmpentry *ep = NULL;    /* avoid gcc warnings */
183         int status;
184         struct stat statb;
185         time_t best = 0;
186         char ftty[sizeof(_PATH_DEV) + sizeof(ep->line)];
187
188         getutentries(NULL, &ep);
189
190 #define SCMPN(a, b)     strncmp(a, b, sizeof (a))
191         status = NOT_HERE;
192         (void) strcpy(ftty, _PATH_DEV);
193         for (; ep; ep = ep->next)
194                 if (SCMPN(ep->name, name) == 0) {
195                         if (*tty == '\0' || best != 0) {
196                                 if (best == 0)
197                                         status = PERMISSION_DENIED;
198                                 /* no particular tty was requested */
199                                 (void) strcpy(ftty + sizeof(_PATH_DEV) - 1,
200                                     ep->line);
201                                 if (stat(ftty, &statb) == 0) {
202                                         if (!(statb.st_mode & 020))
203                                                 continue;
204                                         if (statb.st_atime > best) {
205                                                 best = statb.st_atime;
206                                                 (void) strcpy(tty, ep->line);
207                                                 status = SUCCESS;
208                                                 continue;
209                                         }
210                                 }
211                         }
212                         if (strcmp(ep->line, tty) == 0) {
213                                 status = SUCCESS;
214                                 break;
215                         }
216                 }
217
218         return (status);
219 }