1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 *
22 * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
26 /* All Rights Reserved */
27 /*
28 * University Copyright- Copyright (c) 1982, 1986, 1988
29 * The Regents of the University of California
30 * All Rights Reserved
31 *
32 * University Acknowledgment- Portions of this document are derived from
33 * software developed by the University of California, Berkeley, and its
34 * contributors.
35 */
36
37 #pragma ident "%Z%%M% %I% %E% SMI"
38
39 /*
40 * rwall_subr.c
41 * The server procedure for rwalld
42 */
43
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <unistd.h>
47 #include <rpc/rpc.h>
48 #include <thread.h>
49 #include <rpcsvc/rwall.h>
50 #include <sys/types.h>
51 #include <sys/stat.h>
52 #include <syslog.h>
53 #include <string.h>
54
55 #define WALL_PROG "/usr/sbin/wall"
56
57 static mutex_t wall_mutex = DEFAULTMUTEX;
58 static char *oldmsg;
59
60 /* ARGSUSED */
61 bool_t
wallproc_wall_1_svc(wrapstring * argp,void * res,struct svc_req * rqstp)62 wallproc_wall_1_svc(wrapstring *argp, void *res, struct svc_req *rqstp)
63 {
64 char *msg;
65 FILE *fp;
66 int rval;
67 struct stat wall;
68
69 msg = *argp;
70
71 /*
72 * Do not wall the same message twice in case of a retransmission
73 * in the rare case that two walls arrive close enough with
74 * a retransmission we might get a duplicate, but that is OK.
75 */
76 (void) mutex_lock(&wall_mutex);
77 if ((oldmsg != 0) && (strcmp(msg, oldmsg) == 0)) {
78 (void) mutex_unlock(&wall_mutex);
79 return (TRUE);
80 }
81
82 if (oldmsg)
83 free(oldmsg);
84 oldmsg = strdup(msg);
85
86 rval = stat(WALL_PROG, &wall);
87
88 /*
89 * Make sure the wall programs exists, is executeable, and runs
90 */
91 if (rval == -1 || (wall.st_mode & S_IXUSR) == 0 ||
92 (fp = popen(WALL_PROG, "w")) == NULL) {
93 syslog(LOG_NOTICE,
94 "rwall message received but could not execute %s",
95 WALL_PROG);
96 syslog(LOG_NOTICE, "%s", msg);
97 #ifdef DEBUG
98 (void) fprintf(stderr,
99 "rwall message received but could not execute %s",
100 WALL_PROG);
101 (void) fprintf(stderr, "%s", msg);
102 #endif
103 (void) mutex_unlock(&wall_mutex);
104 return (TRUE);
105 }
106
107 (void) fprintf(fp, "%s", msg);
108 (void) pclose(fp);
109 (void) mutex_unlock(&wall_mutex);
110
111 return (TRUE);
112 }
113
114 /* ARGSUSED */
115 int
wallprog_1_freeresult(SVCXPRT * transp,xdrproc_t proc,caddr_t arg)116 wallprog_1_freeresult(SVCXPRT *transp, xdrproc_t proc, caddr_t arg)
117 {
118 return (TRUE);
119 }
120