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 #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 /* not lint */ 39 40 #ifndef lint 41 #if 0 42 static char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93"; 43 #endif 44 static const char rcsid[] = 45 "$FreeBSD: src/usr.bin/wall/wall.c,v 1.13.2.6 2001/10/18 08:08:17 des Exp $"; 46 #endif /* not lint */ 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 #define IGNOREUSER "sleeper" 76 77 struct wallgroup { 78 struct wallgroup *next; 79 char *name; 80 gid_t gid; 81 } *grouplist; 82 int nobanner; 83 int mbufsize; 84 char *mbuf; 85 86 int 87 main(int argc, char *argv[]) 88 { 89 struct iovec iov; 90 struct utmp utmp; 91 int ch; 92 int ingroup; 93 FILE *fp; 94 struct wallgroup *g; 95 struct group *grp; 96 char **np; 97 const char *p; 98 struct passwd *pw; 99 char line[sizeof(utmp.ut_line) + 1]; 100 char username[sizeof(utmp.ut_name) + 1]; 101 102 (void)setlocale(LC_CTYPE, ""); 103 104 while ((ch = getopt(argc, argv, "g:n")) != -1) 105 switch (ch) { 106 case 'n': 107 /* undoc option for shutdown: suppress banner */ 108 if (geteuid() == 0) 109 nobanner = 1; 110 break; 111 case 'g': 112 g = (struct wallgroup *)malloc(sizeof *g); 113 g->next = grouplist; 114 g->name = optarg; 115 g->gid = -1; 116 grouplist = g; 117 break; 118 case '?': 119 default: 120 usage(); 121 } 122 argc -= optind; 123 argv += optind; 124 if (argc > 1) 125 usage(); 126 127 for (g = grouplist; g; g = g->next) { 128 grp = getgrnam(g->name); 129 if (grp != NULL) 130 g->gid = grp->gr_gid; 131 else 132 warnx("%s: no such group", g->name); 133 } 134 135 makemsg(*argv); 136 137 if (!(fp = fopen(_PATH_UTMP, "r"))) 138 err(1, "cannot read %s", _PATH_UTMP); 139 iov.iov_base = mbuf; 140 iov.iov_len = mbufsize; 141 /* NOSTRICT */ 142 while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) { 143 if (!utmp.ut_name[0] || 144 !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name))) 145 continue; 146 if (grouplist) { 147 ingroup = 0; 148 strlcpy(username, utmp.ut_name, sizeof(utmp.ut_name)); 149 pw = getpwnam(username); 150 if (!pw) 151 continue; 152 for (g = grouplist; g && ingroup == 0; g = g->next) { 153 if (g->gid == -1) 154 continue; 155 if (g->gid == pw->pw_gid) 156 ingroup = 1; 157 else if ((grp = getgrgid(g->gid)) != NULL) { 158 for (np = grp->gr_mem; *np; np++) { 159 if (strcmp(*np, username) == 0) { 160 ingroup = 1; 161 break; 162 } 163 } 164 } 165 } 166 if (ingroup == 0) 167 continue; 168 } 169 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 170 line[sizeof(utmp.ut_line)] = '\0'; 171 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 172 warnx("%s", p); 173 } 174 exit(0); 175 } 176 177 static void 178 usage() 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, *tty, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 196 const char *whom; 197 gid_t egid; 198 199 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 200 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 201 err(1, "can't open temporary file"); 202 (void)unlink(tmpname); 203 204 if (!nobanner) { 205 tty = ttyname(STDERR_FILENO); 206 if (tty == NULL) 207 tty = "no tty"; 208 209 if (!(whom = getlogin())) 210 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 211 (void)gethostname(hostname, sizeof(hostname)); 212 (void)time(&now); 213 lt = localtime(&now); 214 215 /* 216 * all this stuff is to blank out a square for the message; 217 * we wrap message lines at column 79, not 80, because some 218 * terminals wrap after 79, some do not, and we can't tell. 219 * Which means that we may leave a non-blank character 220 * in column 80, but that can't be helped. 221 */ 222 (void)fprintf(fp, "\r%79s\r\n", " "); 223 (void)snprintf(lbuf, sizeof(lbuf), 224 "Broadcast Message from %s@%s", 225 whom, hostname); 226 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 227 (void)snprintf(lbuf, sizeof(lbuf), 228 " (%s) at %d:%02d %s...", tty, 229 lt->tm_hour, lt->tm_min, lt->tm_zone); 230 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 231 } 232 (void)fprintf(fp, "%79s\r\n", " "); 233 234 if (fname) { 235 egid = getegid(); 236 setegid(getgid()); 237 if (freopen(fname, "r", stdin) == NULL) 238 err(1, "can't read %s", fname); 239 setegid(egid); 240 } 241 while (fgets(lbuf, sizeof(lbuf), stdin)) 242 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 243 if (ch == '\r') { 244 cnt = 0; 245 } else if (cnt == 79 || ch == '\n') { 246 for (; cnt < 79; ++cnt) 247 putc(' ', fp); 248 putc('\r', fp); 249 putc('\n', fp); 250 cnt = 0; 251 } else if (((ch & 0x80) && ch < 0xA0) || 252 /* disable upper controls */ 253 (!isprint(ch) && !isspace(ch) && 254 ch != '\a' && ch != '\b') 255 ) { 256 if (ch & 0x80) { 257 ch &= 0x7F; 258 putc('M', fp); 259 if (++cnt == 79) { 260 putc('\r', fp); 261 putc('\n', fp); 262 cnt = 0; 263 } 264 putc('-', fp); 265 if (++cnt == 79) { 266 putc('\r', fp); 267 putc('\n', fp); 268 cnt = 0; 269 } 270 } 271 if (iscntrl(ch)) { 272 ch ^= 040; 273 putc('^', fp); 274 if (++cnt == 79) { 275 putc('\r', fp); 276 putc('\n', fp); 277 cnt = 0; 278 } 279 } 280 putc(ch, fp); 281 } else { 282 putc(ch, fp); 283 } 284 } 285 (void)fprintf(fp, "%79s\r\n", " "); 286 rewind(fp); 287 288 if (fstat(fd, &sbuf)) 289 err(1, "can't stat temporary file"); 290 mbufsize = sbuf.st_size; 291 if (!(mbuf = malloc((u_int)mbufsize))) 292 err(1, "out of memory"); 293 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 294 err(1, "can't read temporary file"); 295 (void)close(fd); 296 } 297