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 /*
38 * rwall_subr.c
39 * The server procedure for rwalld
40 */
41
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <unistd.h>
45 #include <rpc/rpc.h>
46 #include <thread.h>
47 #include <rpcsvc/rwall.h>
48 #include <sys/types.h>
49 #include <sys/stat.h>
50 #include <syslog.h>
51 #include <string.h>
52
53 #define WALL_PROG "/usr/sbin/wall"
54
55 static mutex_t wall_mutex = DEFAULTMUTEX;
56 static char *oldmsg;
57
58 /* ARGSUSED */
59 bool_t
wallproc_wall_1_svc(wrapstring * argp,void * res,struct svc_req * rqstp)60 wallproc_wall_1_svc(wrapstring *argp, void *res, struct svc_req *rqstp)
61 {
62 char *msg;
63 FILE *fp;
64 int rval;
65 struct stat wall;
66
67 msg = *argp;
68
69 /*
70 * Do not wall the same message twice in case of a retransmission
71 * in the rare case that two walls arrive close enough with
72 * a retransmission we might get a duplicate, but that is OK.
73 */
74 (void) mutex_lock(&wall_mutex);
75 if ((oldmsg != 0) && (strcmp(msg, oldmsg) == 0)) {
76 (void) mutex_unlock(&wall_mutex);
77 return (TRUE);
78 }
79
80 if (oldmsg)
81 free(oldmsg);
82 oldmsg = strdup(msg);
83
84 rval = stat(WALL_PROG, &wall);
85
86 /*
87 * Make sure the wall programs exists, is executeable, and runs
88 */
89 if (rval == -1 || (wall.st_mode & S_IXUSR) == 0 ||
90 (fp = popen(WALL_PROG, "w")) == NULL) {
91 syslog(LOG_NOTICE,
92 "rwall message received but could not execute %s",
93 WALL_PROG);
94 syslog(LOG_NOTICE, "%s", msg);
95 #ifdef DEBUG
96 (void) fprintf(stderr,
97 "rwall message received but could not execute %s",
98 WALL_PROG);
99 (void) fprintf(stderr, "%s", msg);
100 #endif
101 (void) mutex_unlock(&wall_mutex);
102 return (TRUE);
103 }
104
105 (void) fprintf(fp, "%s", msg);
106 (void) pclose(fp);
107 (void) mutex_unlock(&wall_mutex);
108
109 return (TRUE);
110 }
111
112 /* ARGSUSED */
113 int
wallprog_1_freeresult(SVCXPRT * transp,xdrproc_t proc,caddr_t arg)114 wallprog_1_freeresult(SVCXPRT *transp, xdrproc_t proc, caddr_t arg)
115 {
116 return (TRUE);
117 }
118