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 * @(#) Copyright (c) 1988, 1990, 1993 The Regents of the University of California. All rights reserved. 34 * @(#)wall.c 8.2 (Berkeley) 11/16/93 35 * $FreeBSD: src/usr.bin/wall/wall.c,v 1.13.2.6 2001/10/18 08:08:17 des Exp $ 36 * $DragonFly: src/usr.bin/wall/wall.c,v 1.3 2003/10/04 20:36:54 hmp Exp $ 37 */ 38 39 /* 40 * This program is not related to David Wall, whose Stanford Ph.D. thesis 41 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 42 */ 43 44 #include <sys/param.h> 45 #include <sys/stat.h> 46 #include <sys/uio.h> 47 48 #include <ctype.h> 49 #include <err.h> 50 #include <grp.h> 51 #include <locale.h> 52 #include <paths.h> 53 #include <pwd.h> 54 #include <stdio.h> 55 #include <stdlib.h> 56 #include <string.h> 57 #include <time.h> 58 #include <unistd.h> 59 #include <utmp.h> 60 61 #include "ttymsg.h" 62 63 static void makemsg(char *); 64 static void usage(void); 65 66 #define IGNOREUSER "sleeper" 67 68 struct wallgroup { 69 struct wallgroup *next; 70 char *name; 71 gid_t gid; 72 } *grouplist; 73 int nobanner; 74 int mbufsize; 75 char *mbuf; 76 77 int 78 main(int argc, char *argv[]) 79 { 80 struct iovec iov; 81 struct utmp utmp; 82 int ch; 83 int ingroup; 84 FILE *fp; 85 struct wallgroup *g; 86 struct group *grp; 87 char **np; 88 const char *p; 89 struct passwd *pw; 90 char line[sizeof(utmp.ut_line) + 1]; 91 char username[sizeof(utmp.ut_name) + 1]; 92 93 (void)setlocale(LC_CTYPE, ""); 94 95 while ((ch = getopt(argc, argv, "g:n")) != -1) 96 switch (ch) { 97 case 'n': 98 /* undoc option for shutdown: suppress banner */ 99 if (geteuid() == 0) 100 nobanner = 1; 101 break; 102 case 'g': 103 g = (struct wallgroup *)malloc(sizeof *g); 104 g->next = grouplist; 105 g->name = optarg; 106 g->gid = -1; 107 grouplist = g; 108 break; 109 case '?': 110 default: 111 usage(); 112 } 113 argc -= optind; 114 argv += optind; 115 if (argc > 1) 116 usage(); 117 118 for (g = grouplist; g; g = g->next) { 119 grp = getgrnam(g->name); 120 if (grp != NULL) 121 g->gid = grp->gr_gid; 122 else 123 warnx("%s: no such group", g->name); 124 } 125 126 makemsg(*argv); 127 128 if (!(fp = fopen(_PATH_UTMP, "r"))) 129 err(1, "cannot read %s", _PATH_UTMP); 130 iov.iov_base = mbuf; 131 iov.iov_len = mbufsize; 132 /* NOSTRICT */ 133 while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) { 134 if (!utmp.ut_name[0] || 135 !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name))) 136 continue; 137 if (grouplist) { 138 ingroup = 0; 139 strlcpy(username, utmp.ut_name, sizeof(utmp.ut_name)); 140 pw = getpwnam(username); 141 if (!pw) 142 continue; 143 for (g = grouplist; g && ingroup == 0; g = g->next) { 144 if (g->gid == -1) 145 continue; 146 if (g->gid == pw->pw_gid) 147 ingroup = 1; 148 else if ((grp = getgrgid(g->gid)) != NULL) { 149 for (np = grp->gr_mem; *np; np++) { 150 if (strcmp(*np, username) == 0) { 151 ingroup = 1; 152 break; 153 } 154 } 155 } 156 } 157 if (ingroup == 0) 158 continue; 159 } 160 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 161 line[sizeof(utmp.ut_line)] = '\0'; 162 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 163 warnx("%s", p); 164 } 165 exit(0); 166 } 167 168 static void 169 usage(void) 170 { 171 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 172 exit(1); 173 } 174 175 void 176 makemsg(char *fname) 177 { 178 int cnt; 179 unsigned char ch; 180 struct tm *lt; 181 struct passwd *pw; 182 struct stat sbuf; 183 time_t now; 184 FILE *fp; 185 int fd; 186 char *p, *tty, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 187 const char *whom; 188 gid_t egid; 189 190 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 191 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 192 err(1, "can't open temporary file"); 193 (void)unlink(tmpname); 194 195 if (!nobanner) { 196 tty = ttyname(STDERR_FILENO); 197 if (tty == NULL) 198 tty = "no tty"; 199 200 if (!(whom = getlogin())) 201 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 202 (void)gethostname(hostname, sizeof(hostname)); 203 (void)time(&now); 204 lt = localtime(&now); 205 206 /* 207 * all this stuff is to blank out a square for the message; 208 * we wrap message lines at column 79, not 80, because some 209 * terminals wrap after 79, some do not, and we can't tell. 210 * Which means that we may leave a non-blank character 211 * in column 80, but that can't be helped. 212 */ 213 (void)fprintf(fp, "\r%79s\r\n", " "); 214 (void)snprintf(lbuf, sizeof(lbuf), 215 "Broadcast Message from %s@%s", 216 whom, hostname); 217 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 218 (void)snprintf(lbuf, sizeof(lbuf), 219 " (%s) at %d:%02d %s...", tty, 220 lt->tm_hour, lt->tm_min, lt->tm_zone); 221 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 222 } 223 (void)fprintf(fp, "%79s\r\n", " "); 224 225 if (fname) { 226 egid = getegid(); 227 setegid(getgid()); 228 if (freopen(fname, "r", stdin) == NULL) 229 err(1, "can't read %s", fname); 230 setegid(egid); 231 } 232 while (fgets(lbuf, sizeof(lbuf), stdin)) 233 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 234 if (ch == '\r') { 235 cnt = 0; 236 } else if (cnt == 79 || ch == '\n') { 237 for (; cnt < 79; ++cnt) 238 putc(' ', fp); 239 putc('\r', fp); 240 putc('\n', fp); 241 cnt = 0; 242 } else if (((ch & 0x80) && ch < 0xA0) || 243 /* disable upper controls */ 244 (!isprint(ch) && !isspace(ch) && 245 ch != '\a' && ch != '\b') 246 ) { 247 if (ch & 0x80) { 248 ch &= 0x7F; 249 putc('M', fp); 250 if (++cnt == 79) { 251 putc('\r', fp); 252 putc('\n', fp); 253 cnt = 0; 254 } 255 putc('-', fp); 256 if (++cnt == 79) { 257 putc('\r', fp); 258 putc('\n', fp); 259 cnt = 0; 260 } 261 } 262 if (iscntrl(ch)) { 263 ch ^= 040; 264 putc('^', fp); 265 if (++cnt == 79) { 266 putc('\r', fp); 267 putc('\n', fp); 268 cnt = 0; 269 } 270 } 271 putc(ch, fp); 272 } else { 273 putc(ch, fp); 274 } 275 } 276 (void)fprintf(fp, "%79s\r\n", " "); 277 rewind(fp); 278 279 if (fstat(fd, &sbuf)) 280 err(1, "can't stat temporary file"); 281 mbufsize = sbuf.st_size; 282 if (!(mbuf = malloc((u_int)mbufsize))) 283 err(1, "out of memory"); 284 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 285 err(1, "can't read temporary file"); 286 (void)close(fd); 287 } 288