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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 36 __FBSDID("$FreeBSD$"); 37 38 #ifndef lint 39 static const char copyright[] = 40 "@(#) Copyright (c) 1988, 1990, 1993\n\ 41 The Regents of the University of California. All rights reserved.\n"; 42 #endif 43 44 #ifndef lint 45 static const char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93"; 46 #endif 47 48 /* 49 * This program is not related to David Wall, whose Stanford Ph.D. thesis 50 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 51 */ 52 53 #include <sys/param.h> 54 #include <sys/stat.h> 55 #include <sys/uio.h> 56 57 #include <ctype.h> 58 #include <err.h> 59 #include <grp.h> 60 #include <locale.h> 61 #include <paths.h> 62 #include <pwd.h> 63 #include <stdio.h> 64 #include <stdlib.h> 65 #include <string.h> 66 #include <time.h> 67 #include <unistd.h> 68 #include <utmpx.h> 69 70 #include "ttymsg.h" 71 72 static void makemsg(char *); 73 static void usage(void); 74 75 struct wallgroup { 76 struct wallgroup *next; 77 char *name; 78 gid_t gid; 79 } *grouplist; 80 int nobanner; 81 int mbufsize; 82 char *mbuf; 83 84 static int 85 ttystat(char *line) 86 { 87 struct stat sb; 88 char ttybuf[MAXPATHLEN]; 89 90 (void)snprintf(ttybuf, sizeof(ttybuf), "%s%s", _PATH_DEV, line); 91 if (stat(ttybuf, &sb) == 0) { 92 return (0); 93 } else 94 return (-1); 95 } 96 97 int 98 main(int argc, char *argv[]) 99 { 100 struct iovec iov; 101 struct utmpx *utmp; 102 int ch; 103 int ingroup; 104 struct wallgroup *g; 105 struct group *grp; 106 char **np; 107 const char *p; 108 struct passwd *pw; 109 110 (void)setlocale(LC_CTYPE, ""); 111 112 while ((ch = getopt(argc, argv, "g:n")) != -1) 113 switch (ch) { 114 case 'n': 115 /* undoc option for shutdown: suppress banner */ 116 if (geteuid() == 0) 117 nobanner = 1; 118 break; 119 case 'g': 120 g = (struct wallgroup *)malloc(sizeof *g); 121 g->next = grouplist; 122 g->name = optarg; 123 g->gid = -1; 124 grouplist = g; 125 break; 126 case '?': 127 default: 128 usage(); 129 } 130 argc -= optind; 131 argv += optind; 132 if (argc > 1) 133 usage(); 134 135 for (g = grouplist; g; g = g->next) { 136 grp = getgrnam(g->name); 137 if (grp != NULL) 138 g->gid = grp->gr_gid; 139 else 140 warnx("%s: no such group", g->name); 141 } 142 143 makemsg(*argv); 144 145 iov.iov_base = mbuf; 146 iov.iov_len = mbufsize; 147 /* NOSTRICT */ 148 while ((utmp = getutxent()) != NULL) { 149 if (utmp->ut_type != USER_PROCESS) 150 continue; 151 if (ttystat(utmp->ut_line) != 0) 152 continue; 153 if (grouplist) { 154 ingroup = 0; 155 pw = getpwnam(utmp->ut_user); 156 if (!pw) 157 continue; 158 for (g = grouplist; g && ingroup == 0; g = g->next) { 159 if (g->gid == (gid_t)-1) 160 continue; 161 if (g->gid == pw->pw_gid) 162 ingroup = 1; 163 else if ((grp = getgrgid(g->gid)) != NULL) { 164 for (np = grp->gr_mem; *np; np++) { 165 if (strcmp(*np, utmp->ut_user) == 0) { 166 ingroup = 1; 167 break; 168 } 169 } 170 } 171 } 172 if (ingroup == 0) 173 continue; 174 } 175 if ((p = ttymsg(&iov, 1, utmp->ut_line, 60*5)) != NULL) 176 warnx("%s", p); 177 } 178 exit(0); 179 } 180 181 static void 182 usage(void) 183 { 184 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 185 exit(1); 186 } 187 188 void 189 makemsg(char *fname) 190 { 191 int cnt; 192 unsigned char ch; 193 struct tm *lt; 194 struct passwd *pw; 195 struct stat sbuf; 196 time_t now; 197 FILE *fp; 198 int fd; 199 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 200 const char *tty; 201 const char *whom; 202 gid_t egid; 203 204 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 205 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 206 err(1, "can't open temporary file"); 207 (void)unlink(tmpname); 208 209 if (!nobanner) { 210 tty = ttyname(STDERR_FILENO); 211 if (tty == NULL) 212 tty = "no tty"; 213 214 if (!(whom = getlogin())) 215 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 216 (void)gethostname(hostname, sizeof(hostname)); 217 (void)time(&now); 218 lt = localtime(&now); 219 220 /* 221 * all this stuff is to blank out a square for the message; 222 * we wrap message lines at column 79, not 80, because some 223 * terminals wrap after 79, some do not, and we can't tell. 224 * Which means that we may leave a non-blank character 225 * in column 80, but that can't be helped. 226 */ 227 (void)fprintf(fp, "\r%79s\r\n", " "); 228 (void)snprintf(lbuf, sizeof(lbuf), 229 "Broadcast Message from %s@%s", 230 whom, hostname); 231 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 232 (void)snprintf(lbuf, sizeof(lbuf), 233 " (%s) at %d:%02d %s...", tty, 234 lt->tm_hour, lt->tm_min, lt->tm_zone); 235 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 236 } 237 (void)fprintf(fp, "%79s\r\n", " "); 238 239 if (fname) { 240 egid = getegid(); 241 setegid(getgid()); 242 if (freopen(fname, "r", stdin) == NULL) 243 err(1, "can't read %s", fname); 244 setegid(egid); 245 } 246 while (fgets(lbuf, sizeof(lbuf), stdin)) { 247 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 248 if (ch == '\r') { 249 putc('\r', fp); 250 cnt = 0; 251 continue; 252 } else if (ch == '\n') { 253 for (; cnt < 79; ++cnt) 254 putc(' ', fp); 255 putc('\r', fp); 256 putc('\n', fp); 257 break; 258 } 259 if (cnt == 79) { 260 putc('\r', fp); 261 putc('\n', fp); 262 cnt = 0; 263 } 264 if (((ch & 0x80) && ch < 0xA0) || 265 /* disable upper controls */ 266 (!isprint(ch) && !isspace(ch) && 267 ch != '\a' && ch != '\b') 268 ) { 269 if (ch & 0x80) { 270 ch &= 0x7F; 271 putc('M', fp); 272 if (++cnt == 79) { 273 putc('\r', fp); 274 putc('\n', fp); 275 cnt = 0; 276 } 277 putc('-', fp); 278 if (++cnt == 79) { 279 putc('\r', fp); 280 putc('\n', fp); 281 cnt = 0; 282 } 283 } 284 if (iscntrl(ch)) { 285 ch ^= 040; 286 putc('^', fp); 287 if (++cnt == 79) { 288 putc('\r', fp); 289 putc('\n', fp); 290 cnt = 0; 291 } 292 } 293 } 294 putc(ch, fp); 295 } 296 } 297 (void)fprintf(fp, "%79s\r\n", " "); 298 rewind(fp); 299 300 if (fstat(fd, &sbuf)) 301 err(1, "can't stat temporary file"); 302 mbufsize = sbuf.st_size; 303 if (!(mbuf = malloc((u_int)mbufsize))) 304 err(1, "out of memory"); 305 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 306 err(1, "can't read temporary file"); 307 (void)close(fd); 308 } 309