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 "$FreeBSD$"; 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 static void makemsg(char *); 71 static void usage(void); 72 char *ttymsg(struct iovec *, int, const char *, int); 73 74 #define IGNOREUSER "sleeper" 75 76 struct wallgroup { 77 struct wallgroup *next; 78 char *name; 79 gid_t gid; 80 } *grouplist; 81 int nobanner; 82 int mbufsize; 83 char *mbuf; 84 85 int 86 main(int argc, char *argv[]) 87 { 88 struct iovec iov; 89 struct utmp utmp; 90 gid_t grps[NGROUPS_MAX]; 91 int ch; 92 int ingroup, ngrps, i; 93 FILE *fp; 94 struct wallgroup *g; 95 struct group *grp; 96 char *p; 97 struct passwd *pw; 98 char line[sizeof(utmp.ut_line) + 1]; 99 char username[sizeof(utmp.ut_name) + 1]; 100 101 ingroup = 0; 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 strlcpy(username, utmp.ut_name, sizeof(utmp.ut_name)); 148 pw = getpwnam(username); 149 if (!pw) 150 continue; 151 ngrps = getgroups(pw->pw_gid, grps); 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 for (i = 0; i < ngrps && ingroup == 0; i++) 158 if (g->gid == grps[i]) 159 ingroup = 1; 160 } 161 if (ingroup == 0) 162 continue; 163 } 164 strncpy(line, utmp.ut_line, sizeof(utmp.ut_line)); 165 line[sizeof(utmp.ut_line)] = '\0'; 166 if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL) 167 warnx("%s", p); 168 } 169 exit(0); 170 } 171 172 static void 173 usage() 174 { 175 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 176 exit(1); 177 } 178 179 void 180 makemsg(char *fname) 181 { 182 int cnt; 183 unsigned char ch; 184 struct tm *lt; 185 struct passwd *pw; 186 struct stat sbuf; 187 time_t now; 188 FILE *fp; 189 int fd; 190 char *p, *tty, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64]; 191 const char *whom; 192 gid_t egid; 193 194 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 195 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 196 err(1, "can't open temporary file"); 197 (void)unlink(tmpname); 198 199 if (!nobanner) { 200 tty = ttyname(STDERR_FILENO); 201 if (tty == NULL) 202 tty = "no tty"; 203 204 if (!(whom = getlogin())) 205 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 206 (void)gethostname(hostname, sizeof(hostname)); 207 (void)time(&now); 208 lt = localtime(&now); 209 210 /* 211 * all this stuff is to blank out a square for the message; 212 * we wrap message lines at column 79, not 80, because some 213 * terminals wrap after 79, some do not, and we can't tell. 214 * Which means that we may leave a non-blank character 215 * in column 80, but that can't be helped. 216 */ 217 (void)fprintf(fp, "\r%79s\r\n", " "); 218 (void)snprintf(lbuf, sizeof(lbuf), 219 "Broadcast Message from %s@%s", 220 whom, hostname); 221 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 222 (void)snprintf(lbuf, sizeof(lbuf), 223 " (%s) at %d:%02d %s...", tty, 224 lt->tm_hour, lt->tm_min, lt->tm_zone); 225 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 226 } 227 (void)fprintf(fp, "%79s\r\n", " "); 228 229 if (fname) { 230 egid = getegid(); 231 setegid(getgid()); 232 if (freopen(fname, "r", stdin) == NULL) 233 err(1, "can't read %s", fname); 234 setegid(egid); 235 } 236 while (fgets(lbuf, sizeof(lbuf), stdin)) 237 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 238 if (ch == '\r') { 239 cnt = 0; 240 } else if (cnt == 79 || ch == '\n') { 241 for (; cnt < 79; ++cnt) 242 putc(' ', fp); 243 putc('\r', fp); 244 putc('\n', fp); 245 cnt = 0; 246 } else if (((ch & 0x80) && ch < 0xA0) || 247 /* disable upper controls */ 248 (!isprint(ch) && !isspace(ch) && 249 ch != '\a' && ch != '\b') 250 ) { 251 if (ch & 0x80) { 252 ch &= 0x7F; 253 putc('M', fp); 254 if (++cnt == 79) { 255 putc('\r', fp); 256 putc('\n', fp); 257 cnt = 0; 258 } 259 putc('-', fp); 260 if (++cnt == 79) { 261 putc('\r', fp); 262 putc('\n', fp); 263 cnt = 0; 264 } 265 } 266 if (iscntrl(ch)) { 267 ch ^= 040; 268 putc('^', fp); 269 if (++cnt == 79) { 270 putc('\r', fp); 271 putc('\n', fp); 272 cnt = 0; 273 } 274 } 275 putc(ch, fp); 276 } else { 277 putc(ch, fp); 278 } 279 } 280 (void)fprintf(fp, "%79s\r\n", " "); 281 rewind(fp); 282 283 if (fstat(fd, &sbuf)) 284 err(1, "can't stat temporary file"); 285 mbufsize = sbuf.st_size; 286 if (!(mbuf = malloc((u_int)mbufsize))) 287 err(1, "out of memory"); 288 if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 289 err(1, "can't read temporary file"); 290 (void)close(fd); 291 } 292