1 /*
2 * Copyright (c) 1988, 1990, 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 * @(#) Copyright (c) 1988, 1990, 1993 The Regents of the University of California. All rights reserved.
30 * @(#)wall.c 8.2 (Berkeley) 11/16/93
31 * $FreeBSD: src/usr.bin/wall/wall.c,v 1.13.2.6 2001/10/18 08:08:17 des Exp $
32 */
33
34 /*
35 * This program is not related to David Wall, whose Stanford Ph.D. thesis
36 * is entitled "Mechanisms for Broadcast and Selective Broadcast".
37 */
38
39 #include <sys/param.h>
40 #include <sys/stat.h>
41 #include <sys/uio.h>
42
43 #include <ctype.h>
44 #include <err.h>
45 #include <grp.h>
46 #include <locale.h>
47 #include <paths.h>
48 #include <pwd.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <time.h>
53 #include <unistd.h>
54 #include "utmpentry.h"
55
56 #include "ttymsg.h"
57
58 static void makemsg(char *);
59 static void usage(void);
60
61 static struct wallgroup {
62 struct wallgroup *next;
63 char *name;
64 gid_t gid;
65 } *grouplist;
66 static int nobanner;
67 static int mbufsize;
68 static char *mbuf;
69
70 int
main(int argc,char * argv[])71 main(int argc, char *argv[])
72 {
73 struct iovec iov;
74 struct utmpentry *ep = NULL; /* avoid gcc warnings */
75 int ch;
76 int ingroup;
77 struct wallgroup *g;
78 struct group *grp;
79 char **np;
80 const char *p;
81 struct passwd *pw;
82
83 (void)setlocale(LC_CTYPE, "");
84
85 while ((ch = getopt(argc, argv, "g:n")) != -1)
86 switch (ch) {
87 case 'n':
88 /* undoc option for shutdown: suppress banner */
89 if (geteuid() == 0)
90 nobanner = 1;
91 break;
92 case 'g':
93 g = (struct wallgroup *)malloc(sizeof *g);
94 g->next = grouplist;
95 g->name = optarg;
96 g->gid = -1;
97 grouplist = g;
98 break;
99 case '?':
100 default:
101 usage();
102 }
103 argc -= optind;
104 argv += optind;
105 if (argc > 1)
106 usage();
107
108 for (g = grouplist; g; g = g->next) {
109 grp = getgrnam(g->name);
110 if (grp != NULL)
111 g->gid = grp->gr_gid;
112 else
113 warnx("%s: no such group", g->name);
114 }
115
116 makemsg(*argv);
117
118 iov.iov_base = mbuf;
119 iov.iov_len = mbufsize;
120
121 getutentries(NULL, &ep);
122 /* NOSTRICT */
123 for (; ep; ep = ep->next) {
124 if (grouplist) {
125 ingroup = 0;
126 pw = getpwnam(ep->name);
127 if (!pw)
128 continue;
129 for (g = grouplist; g && ingroup == 0; g = g->next) {
130 if (g->gid == (gid_t)-1)
131 continue;
132 if (g->gid == pw->pw_gid)
133 ingroup = 1;
134 else if ((grp = getgrgid(g->gid)) != NULL) {
135 for (np = grp->gr_mem; *np; np++) {
136 if (strcmp(*np, ep->name) == 0) {
137 ingroup = 1;
138 break;
139 }
140 }
141 }
142 }
143 if (ingroup == 0)
144 continue;
145 }
146 /* skip [xgk]dm/xserver entries (":0", ":1", etc.) */
147 if (ep->line[0] == ':' && isdigit((unsigned char)ep->line[1]))
148 continue;
149
150 if ((p = ttymsg(&iov, 1, ep->line, 60*5)) != NULL)
151 warnx("%s", p);
152 }
153 exit(0);
154 }
155
156 static void
usage(void)157 usage(void)
158 {
159 (void)fprintf(stderr, "usage: wall [-g group] [file]\n");
160 exit(1);
161 }
162
163 void
makemsg(char * fname)164 makemsg(char *fname)
165 {
166 int cnt;
167 unsigned char ch;
168 struct tm *lt;
169 struct passwd *pw;
170 struct stat sbuf;
171 time_t now;
172 FILE *fp;
173 int fd;
174 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[MAXPATHLEN];
175 const char *tty;
176 const char *whom;
177 gid_t egid;
178
179 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
180 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+")))
181 err(1, "can't open temporary file");
182 (void)unlink(tmpname);
183
184 if (!nobanner) {
185 tty = ttyname(STDERR_FILENO);
186 if (tty == NULL)
187 tty = "no tty";
188
189 if (!(whom = getlogin()))
190 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
191 (void)gethostname(hostname, sizeof(hostname));
192 (void)time(&now);
193 lt = localtime(&now);
194
195 /*
196 * all this stuff is to blank out a square for the message;
197 * we wrap message lines at column 79, not 80, because some
198 * terminals wrap after 79, some do not, and we can't tell.
199 * Which means that we may leave a non-blank character
200 * in column 80, but that can't be helped.
201 */
202 (void)fprintf(fp, "\r%79s\r\n", " ");
203 (void)snprintf(lbuf, sizeof(lbuf),
204 "Broadcast Message from %s@%s",
205 whom, hostname);
206 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf);
207 (void)snprintf(lbuf, sizeof(lbuf),
208 " (%s) at %d:%02d %s...", tty,
209 lt->tm_hour, lt->tm_min, lt->tm_zone);
210 (void)fprintf(fp, "%-79.79s\r\n", lbuf);
211 }
212 (void)fprintf(fp, "%79s\r\n", " ");
213
214 if (fname) {
215 egid = getegid();
216 setegid(getgid());
217 if (freopen(fname, "r", stdin) == NULL)
218 err(1, "can't read %s", fname);
219 setegid(egid);
220 }
221 while (fgets(lbuf, sizeof(lbuf), stdin))
222 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
223 if (ch == '\r') {
224 cnt = 0;
225 } else if (cnt == 79 || ch == '\n') {
226 for (; cnt < 79; ++cnt)
227 putc(' ', fp);
228 putc('\r', fp);
229 putc('\n', fp);
230 cnt = 0;
231 } else if (((ch & 0x80) && ch < 0xA0) ||
232 /* disable upper controls */
233 (!isprint(ch) && !isspace(ch) &&
234 ch != '\a' && ch != '\b')
235 ) {
236 if (ch & 0x80) {
237 ch &= 0x7F;
238 putc('M', fp);
239 if (++cnt == 79) {
240 putc('\r', fp);
241 putc('\n', fp);
242 cnt = 0;
243 }
244 putc('-', fp);
245 if (++cnt == 79) {
246 putc('\r', fp);
247 putc('\n', fp);
248 cnt = 0;
249 }
250 }
251 if (iscntrl(ch)) {
252 ch ^= 040;
253 putc('^', fp);
254 if (++cnt == 79) {
255 putc('\r', fp);
256 putc('\n', fp);
257 cnt = 0;
258 }
259 }
260 putc(ch, fp);
261 } else {
262 putc(ch, fp);
263 }
264 }
265 (void)fprintf(fp, "%79s\r\n", " ");
266 rewind(fp);
267
268 if (fstat(fd, &sbuf))
269 err(1, "can't stat temporary file");
270 mbufsize = sbuf.st_size;
271 if (!(mbuf = malloc((u_int)mbufsize)))
272 err(1, "out of memory");
273 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
274 err(1, "can't read temporary file");
275 (void)close(fd);
276 }
277