1 /* $OpenBSD: rwall.c,v 1.13 2015/01/16 06:40:11 deraadt Exp $ */
2
3 /*
4 * Copyright (c) 1993 Christopher G. Demetriou
5 * Copyright (c) 1988, 1990 Regents of the University of California.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * This program is not related to David Wall, whose Stanford Ph.D. thesis
35 * is entitled "Mechanisms for Broadcast and Selective Broadcast".
36 */
37
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <time.h>
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <pwd.h>
45 #include <unistd.h>
46 #include <limits.h>
47 #include <paths.h>
48 #include <err.h>
49
50 #include <rpc/rpc.h>
51 #include <rpcsvc/rwall.h>
52
53 struct timeval timeout = { 25, 0 };
54 int mbufsize;
55 char *mbuf;
56
57 void makemsg(char *);
58
59 int
main(int argc,char * argv[])60 main(int argc, char *argv[])
61 {
62 extern char *__progname;
63 char *wallhost, res;
64 CLIENT *cl;
65
66 if ((argc < 2) || (argc > 3)) {
67 fprintf(stderr, "usage: %s host [file]\n", __progname);
68 exit(1);
69 }
70
71 wallhost = argv[1];
72
73 makemsg(argv[2]);
74
75 /*
76 * Create client "handle" used for calling MESSAGEPROG on the
77 * server designated on the command line. We tell the rpc package
78 * to use the "tcp" protocol when contacting the server.
79 */
80 cl = clnt_create(wallhost, WALLPROG, WALLVERS, "udp");
81 if (cl == NULL) {
82 /*
83 * Couldn't establish connection with server.
84 * Print error message and die.
85 */
86 clnt_pcreateerror(wallhost);
87 exit(1);
88 }
89
90 if (clnt_call(cl, WALLPROC_WALL, xdr_wrapstring, &mbuf, xdr_void,
91 &res, timeout) != RPC_SUCCESS) {
92 /*
93 * An error occurred while calling the server.
94 * Print error message and die.
95 */
96 clnt_perror(cl, wallhost);
97 exit(1);
98 }
99
100 exit(0);
101 }
102
103 void
makemsg(char * fname)104 makemsg(char *fname)
105 {
106 struct tm *lt;
107 struct passwd *pw;
108 struct stat sbuf;
109 time_t now;
110 FILE *fp;
111 int fd;
112 char *whom, hostname[HOST_NAME_MAX+1], lbuf[100], tmpname[PATH_MAX];
113
114 snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXXXXXX", _PATH_TMP);
115 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+")))
116 err(1, "can't open temporary file");
117 (void)unlink(tmpname);
118
119 if (!(whom = getlogin()))
120 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
121 (void)gethostname(hostname, sizeof(hostname));
122 (void)time(&now);
123 lt = localtime(&now);
124
125 /*
126 * all this stuff is to blank out a square for the message;
127 * we wrap message lines at column 79, not 80, because some
128 * terminals wrap after 79, some do not, and we can't tell.
129 * Which means that we may leave a non-blank character
130 * in column 80, but that can't be helped.
131 */
132 (void)fprintf(fp, "Remote Broadcast Message from %s@%s\n",
133 whom, hostname);
134 (void)fprintf(fp, " (%s) at %d:%02d ...\n", ttyname(2),
135 lt->tm_hour, lt->tm_min);
136
137 putc('\n', fp);
138
139 if (fname && !(freopen(fname, "r", stdin)))
140 err(1, "%s", fname);
141 while (fgets(lbuf, sizeof(lbuf), stdin))
142 fputs(lbuf, fp);
143 rewind(fp);
144
145 if (fstat(fd, &sbuf))
146 err(1, "can't stat temporary file");
147 mbufsize = sbuf.st_size;
148 if (!(mbuf = malloc((u_int)mbufsize)))
149 err(1, "malloc");
150 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
151 err(1, "can't read temporary file");
152 (void)close(fd);
153 }
154