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 <utmp.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, int sz) 86 { 87 struct stat sb; 88 char ttybuf[MAXPATHLEN]; 89 90 (void)snprintf(ttybuf, sizeof(ttybuf), "%s%.*s", _PATH_DEV, sz, 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 utmp utmp; 102 int ch; 103 int ingroup; 104 FILE *fp; 105 struct wallgroup *g; 106 struct group *grp; 107 char **np; 108 const char *p; 109 struct passwd *pw; 110 char line[sizeof(utmp.ut_line) + 1]; 111 char username[sizeof(utmp.ut_name) + 1]; 112 113 (void)setlocale(LC_CTYPE, ""); 114 115 while ((ch = getopt(argc, argv, "g:n")) != -1) 116 switch (ch) { 117 case 'n': 118 /* undoc option for shutdown: suppress banner */ 119 if (geteuid() == 0) 120 nobanner = 1; 121 break; 122 case 'g': 123 g = (struct wallgroup *)malloc(sizeof *g); 124 g->next = grouplist; 125 g->name = optarg; 126 g->gid = -1; 127 grouplist = g; 128 break; 129 case '?': 130 default: 131 usage(); 132 } 133 argc -= optind; 134 argv += optind; 135 if (argc > 1) 136 usage(); 137 138 for (g = grouplist; g; g = g->next) { 139 grp = getgrnam(g->name); 140 if (grp != NULL) 141 g->gid = grp->gr_gid; 142 else 143 warnx("%s: no such group", g->name); 144 } 145 146 makemsg(*argv); 147 148 if (!(fp = fopen(_PATH_UTMP, "r"))) 149 err(1, "cannot read %s", _PATH_UTMP); 150 iov.iov_base = mbuf; 151 iov.iov_len = mbufsize; 152 /* NOSTRICT */ 153 while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) { 154 if (!utmp.ut_name[0]) 155 continue; 156 if (ttystat(utmp.ut_line, UT_LINESIZE) != 0) 157 continue; 158 if (grouplist) { 159 ingroup = 0; 160 strlcpy(username, utmp.ut_name, sizeof(utmp.ut_name)); 161 pw = getpwnam(username); 162 if (!pw) 163 continue; 164 for (g = grouplist; g && ingroup == 0; g = g->next) { 165 if (g->gid == (gid_t)-1) 166 continue; 167 if (g->gid == pw->pw_gid) 168 ingroup = 1; 169 else if ((grp = getgrgid(g->gid)) != NULL) { 170 for (np = grp->gr_mem; *np; np++) { 171 if (strcmp(*np, username) == 0) { 172 ingroup = 1; 173 break; 174 } 175 } 176 } 177 } 178 if (ingroup == 0) 179 continue; 180 } 181 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 182 line[sizeof(utmp.ut_line)] = '\0'; 183 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 184 warnx("%s", p); 185 } 186 exit(0); 187 } 188 189 static void 190 usage() 191 { 192 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 193 exit(1); 194 } 195 196 void 197 makemsg(char *fname) 198 { 199 int cnt; 200 unsigned char ch; 201 struct tm *lt; 202 struct passwd *pw; 203 struct stat sbuf; 204 time_t now; 205 FILE *fp; 206 int fd; 207 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 208 const char *tty; 209 const char *whom; 210 gid_t egid; 211 212 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 213 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 214 err(1, "can't open temporary file"); 215 (void)unlink(tmpname); 216 217 if (!nobanner) { 218 tty = ttyname(STDERR_FILENO); 219 if (tty == NULL) 220 tty = "no tty"; 221 222 if (!(whom = getlogin())) 223 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 224 (void)gethostname(hostname, sizeof(hostname)); 225 (void)time(&now); 226 lt = localtime(&now); 227 228 /* 229 * all this stuff is to blank out a square for the message; 230 * we wrap message lines at column 79, not 80, because some 231 * terminals wrap after 79, some do not, and we can't tell. 232 * Which means that we may leave a non-blank character 233 * in column 80, but that can't be helped. 234 */ 235 (void)fprintf(fp, "\r%79s\r\n", " "); 236 (void)snprintf(lbuf, sizeof(lbuf), 237 "Broadcast Message from %s@%s", 238 whom, hostname); 239 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 240 (void)snprintf(lbuf, sizeof(lbuf), 241 " (%s) at %d:%02d %s...", tty, 242 lt->tm_hour, lt->tm_min, lt->tm_zone); 243 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 244 } 245 (void)fprintf(fp, "%79s\r\n", " "); 246 247 if (fname) { 248 egid = getegid(); 249 setegid(getgid()); 250 if (freopen(fname, "r", stdin) == NULL) 251 err(1, "can't read %s", fname); 252 setegid(egid); 253 } 254 while (fgets(lbuf, sizeof(lbuf), stdin)) 255 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 256 if (ch == '\r') { 257 cnt = 0; 258 } else if (cnt == 79 || ch == '\n') { 259 for (; cnt < 79; ++cnt) 260 putc(' ', fp); 261 putc('\r', fp); 262 putc('\n', fp); 263 cnt = 0; 264 } else 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 putc(ch, fp); 294 } else { 295 putc(ch, fp); 296 } 297 } 298 (void)fprintf(fp, "%79s\r\n", " "); 299 rewind(fp); 300 301 if (fstat(fd, &sbuf)) 302 err(1, "can't stat temporary file"); 303 mbufsize = sbuf.st_size; 304 if (!(mbuf = malloc((u_int)mbufsize))) 305 err(1, "out of memory"); 306 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 307 err(1, "can't read temporary file"); 308 (void)close(fd); 309 } 310