rwalld.c revision 1.13 1 /* $NetBSD: rwalld.c,v 1.13 1998/08/10 02:57:24 perry Exp $ */
2
3 /*
4 * Copyright (c) 1993 Christopher G. Demetriou
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote
16 * products derived from this software without specific prior written
17 * permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
20 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
23 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __RCSID("$NetBSD: rwalld.c,v 1.13 1998/08/10 02:57:24 perry Exp $");
35 #endif /* not lint */
36
37 #include <unistd.h>
38 #include <stdlib.h>
39 #include <sys/types.h>
40 #include <pwd.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <syslog.h>
44 #include <errno.h>
45 #include <sys/socket.h>
46 #include <signal.h>
47 #include <sys/wait.h>
48 #include <rpc/rpc.h>
49 #include <rpcsvc/rwall.h>
50
51 #ifdef OSF
52 #define WALL_CMD "/usr/sbin/wall"
53 #else
54 #define WALL_CMD "/usr/bin/wall -n"
55 #endif
56
57 static int from_inetd = 1;
58
59 static void cleanup __P((int));
60 static void wallprog_1 __P((struct svc_req *, SVCXPRT *));
61
62 int main __P((int, char *[]));
63
64 static void
65 cleanup(n)
66 int n;
67 {
68
69 (void)pmap_unset(WALLPROG, WALLVERS);
70 exit(0);
71 }
72
73 int
74 main(argc, argv)
75 int argc;
76 char *argv[];
77 {
78 SVCXPRT *transp;
79 int sock = 0;
80 int proto = 0;
81 struct sockaddr_in from;
82 int fromlen;
83
84 if (geteuid() == 0) {
85 struct passwd *pep = getpwnam("nobody");
86 if (pep)
87 setuid(pep->pw_uid);
88 else
89 setuid(getuid());
90 }
91
92 /*
93 * See if inetd started us
94 */
95 fromlen = sizeof(from);
96 if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0) {
97 from_inetd = 0;
98 sock = RPC_ANYSOCK;
99 proto = IPPROTO_UDP;
100 }
101
102 if (!from_inetd) {
103 daemon(0, 0);
104
105 (void) pmap_unset(WALLPROG, WALLVERS);
106
107 (void) signal(SIGINT, cleanup);
108 (void) signal(SIGTERM, cleanup);
109 (void) signal(SIGHUP, cleanup);
110 }
111
112 openlog("rpc.rwalld", LOG_CONS|LOG_PID, LOG_DAEMON);
113
114 transp = svcudp_create(sock);
115 if (transp == NULL) {
116 syslog(LOG_ERR, "cannot create udp service.");
117 exit(1);
118 }
119 if (!svc_register(transp, WALLPROG, WALLVERS, wallprog_1, proto)) {
120 syslog(LOG_ERR, "unable to register (WALLPROG, WALLVERS, %s).", proto?"udp":"(inetd)");
121 exit(1);
122 }
123
124 svc_run();
125 syslog(LOG_ERR, "svc_run returned");
126 exit(1);
127
128 }
129
130 void *
131 wallproc_wall_1_svc(s, rqstp )
132 char **s;
133 struct svc_req *rqstp;
134 {
135 FILE *pfp;
136
137 pfp = popen(WALL_CMD, "w");
138 if (pfp != NULL) {
139 fprintf(pfp, "\007\007%s", *s);
140 pclose(pfp);
141 }
142
143 return (*s);
144 }
145
146 static void
147 wallprog_1(rqstp, transp)
148 struct svc_req *rqstp;
149 SVCXPRT *transp;
150 {
151 union {
152 char *wallproc_wall_1_arg;
153 } argument;
154 char *result;
155 xdrproc_t xdr_argument, xdr_result;
156 char *(*local) __P((char **, struct svc_req *));
157
158 switch (rqstp->rq_proc) {
159 case NULLPROC:
160 (void)svc_sendreply(transp, xdr_void, (char *)NULL);
161 goto leave;
162
163 case WALLPROC_WALL:
164 xdr_argument = (xdrproc_t)xdr_wrapstring;
165 xdr_result = (xdrproc_t)xdr_void;
166 local = (char *(*) __P((char **, struct svc_req *)))
167 wallproc_wall_1_svc;
168 break;
169
170 default:
171 svcerr_noproc(transp);
172 goto leave;
173 }
174 memset((char *)&argument, 0, sizeof(argument));
175 if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) {
176 svcerr_decode(transp);
177 goto leave;
178 }
179 result = (*local)((char **)&argument, rqstp);
180 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
181 svcerr_systemerr(transp);
182 }
183 if (!svc_freeargs(transp, xdr_argument, (caddr_t)&argument)) {
184 syslog(LOG_ERR, "unable to free arguments");
185 exit(1);
186 }
187 leave:
188 if (from_inetd)
189 exit(0);
190 }
191