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 * 4. 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 30 #include <sys/cdefs.h> 31 32 __FBSDID("$FreeBSD$"); 33 34 #ifndef lint 35 static const char copyright[] = 36 "@(#) Copyright (c) 1988, 1990, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38 #endif 39 40 #ifndef lint 41 static const char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93"; 42 #endif 43 44 /* 45 * This program is not related to David Wall, whose Stanford Ph.D. thesis 46 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 47 */ 48 49 #include <sys/param.h> 50 #include <sys/stat.h> 51 #include <sys/uio.h> 52 53 #include <ctype.h> 54 #include <err.h> 55 #include <grp.h> 56 #include <locale.h> 57 #include <paths.h> 58 #include <pwd.h> 59 #include <stdio.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <time.h> 63 #include <unistd.h> 64 #include <utmpx.h> 65 66 #include "ttymsg.h" 67 68 static void makemsg(char *); 69 static void usage(void); 70 71 static struct wallgroup { 72 struct wallgroup *next; 73 char *name; 74 gid_t gid; 75 } *grouplist; 76 static int nobanner; 77 static int mbufsize; 78 static char *mbuf; 79 80 static int 81 ttystat(char *line) 82 { 83 struct stat sb; 84 char ttybuf[MAXPATHLEN]; 85 86 (void)snprintf(ttybuf, sizeof(ttybuf), "%s%s", _PATH_DEV, line); 87 if (stat(ttybuf, &sb) == 0) { 88 return (0); 89 } else 90 return (-1); 91 } 92 93 int 94 main(int argc, char *argv[]) 95 { 96 struct iovec iov; 97 struct utmpx *utmp; 98 int ch; 99 int ingroup; 100 struct wallgroup *g; 101 struct group *grp; 102 char **np; 103 const char *p; 104 struct passwd *pw; 105 106 (void)setlocale(LC_CTYPE, ""); 107 108 while ((ch = getopt(argc, argv, "g:n")) != -1) 109 switch (ch) { 110 case 'n': 111 /* undoc option for shutdown: suppress banner */ 112 if (geteuid() == 0) 113 nobanner = 1; 114 break; 115 case 'g': 116 g = (struct wallgroup *)malloc(sizeof *g); 117 g->next = grouplist; 118 g->name = optarg; 119 g->gid = -1; 120 grouplist = g; 121 break; 122 case '?': 123 default: 124 usage(); 125 } 126 argc -= optind; 127 argv += optind; 128 if (argc > 1) 129 usage(); 130 131 for (g = grouplist; g; g = g->next) { 132 grp = getgrnam(g->name); 133 if (grp != NULL) 134 g->gid = grp->gr_gid; 135 else 136 warnx("%s: no such group", g->name); 137 } 138 139 makemsg(*argv); 140 141 iov.iov_base = mbuf; 142 iov.iov_len = mbufsize; 143 /* NOSTRICT */ 144 while ((utmp = getutxent()) != NULL) { 145 if (utmp->ut_type != USER_PROCESS) 146 continue; 147 if (ttystat(utmp->ut_line) != 0) 148 continue; 149 if (grouplist) { 150 ingroup = 0; 151 pw = getpwnam(utmp->ut_user); 152 if (!pw) 153 continue; 154 for (g = grouplist; g && ingroup == 0; g = g->next) { 155 if (g->gid == (gid_t)-1) 156 continue; 157 if (g->gid == pw->pw_gid) 158 ingroup = 1; 159 else if ((grp = getgrgid(g->gid)) != NULL) { 160 for (np = grp->gr_mem; *np; np++) { 161 if (strcmp(*np, utmp->ut_user) == 0) { 162 ingroup = 1; 163 break; 164 } 165 } 166 } 167 } 168 if (ingroup == 0) 169 continue; 170 } 171 if ((p = ttymsg(&iov, 1, utmp->ut_line, 60*5)) != NULL) 172 warnx("%s", p); 173 } 174 exit(0); 175 } 176 177 static void 178 usage(void) 179 { 180 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 181 exit(1); 182 } 183 184 void 185 makemsg(char *fname) 186 { 187 int cnt; 188 unsigned char ch; 189 struct tm *lt; 190 struct passwd *pw; 191 struct stat sbuf; 192 time_t now; 193 FILE *fp; 194 int fd; 195 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 196 const char *tty; 197 const char *whom; 198 gid_t egid; 199 200 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 201 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 202 err(1, "can't open temporary file"); 203 (void)unlink(tmpname); 204 205 if (!nobanner) { 206 tty = ttyname(STDERR_FILENO); 207 if (tty == NULL) 208 tty = "no tty"; 209 210 if (!(whom = getlogin())) 211 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 212 (void)gethostname(hostname, sizeof(hostname)); 213 (void)time(&now); 214 lt = localtime(&now); 215 216 /* 217 * all this stuff is to blank out a square for the message; 218 * we wrap message lines at column 79, not 80, because some 219 * terminals wrap after 79, some do not, and we can't tell. 220 * Which means that we may leave a non-blank character 221 * in column 80, but that can't be helped. 222 */ 223 (void)fprintf(fp, "\r%79s\r\n", " "); 224 (void)snprintf(lbuf, sizeof(lbuf), 225 "Broadcast Message from %s@%s", 226 whom, hostname); 227 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 228 (void)snprintf(lbuf, sizeof(lbuf), 229 " (%s) at %d:%02d %s...", tty, 230 lt->tm_hour, lt->tm_min, lt->tm_zone); 231 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 232 } 233 (void)fprintf(fp, "%79s\r\n", " "); 234 235 if (fname) { 236 egid = getegid(); 237 setegid(getgid()); 238 if (freopen(fname, "r", stdin) == NULL) 239 err(1, "can't read %s", fname); 240 setegid(egid); 241 } 242 cnt = 0; 243 while (fgets(lbuf, sizeof(lbuf), stdin)) { 244 for (p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 245 if (ch == '\r') { 246 putc('\r', fp); 247 cnt = 0; 248 continue; 249 } else if (ch == '\n') { 250 for (; cnt < 79; ++cnt) 251 putc(' ', fp); 252 putc('\r', fp); 253 putc('\n', fp); 254 break; 255 } 256 if (cnt == 79) { 257 putc('\r', fp); 258 putc('\n', fp); 259 cnt = 0; 260 } 261 if (((ch & 0x80) && ch < 0xA0) || 262 /* disable upper controls */ 263 (!isprint(ch) && !isspace(ch) && 264 ch != '\a' && ch != '\b') 265 ) { 266 if (ch & 0x80) { 267 ch &= 0x7F; 268 putc('M', fp); 269 if (++cnt == 79) { 270 putc('\r', fp); 271 putc('\n', fp); 272 cnt = 0; 273 } 274 putc('-', fp); 275 if (++cnt == 79) { 276 putc('\r', fp); 277 putc('\n', fp); 278 cnt = 0; 279 } 280 } 281 if (iscntrl(ch)) { 282 ch ^= 040; 283 putc('^', fp); 284 if (++cnt == 79) { 285 putc('\r', fp); 286 putc('\n', fp); 287 cnt = 0; 288 } 289 } 290 } 291 putc(ch, fp); 292 } 293 } 294 (void)fprintf(fp, "%79s\r\n", " "); 295 rewind(fp); 296 297 if (fstat(fd, &sbuf)) 298 err(1, "can't stat temporary file"); 299 mbufsize = sbuf.st_size; 300 if (!(mbuf = malloc((u_int)mbufsize))) 301 err(1, "out of memory"); 302 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 303 err(1, "can't read temporary file"); 304 (void)close(fd); 305 } 306