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 1.4 2005/08/31 16:27:53 liamfoy 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 "utmpentry.h" 60 61 #include "ttymsg.h" 62 63 static void makemsg(char *); 64 static void usage(void); 65 66 struct wallgroup { 67 struct wallgroup *next; 68 char *name; 69 gid_t gid; 70 } *grouplist; 71 int nobanner; 72 int mbufsize; 73 char *mbuf; 74 75 int 76 main(int argc, char *argv[]) 77 { 78 struct iovec iov; 79 struct utmpentry *ep; 80 int ch; 81 int ingroup; 82 struct wallgroup *g; 83 struct group *grp; 84 char **np; 85 const char *p; 86 struct passwd *pw; 87 88 (void)setlocale(LC_CTYPE, ""); 89 90 while ((ch = getopt(argc, argv, "g:n")) != -1) 91 switch (ch) { 92 case 'n': 93 /* undoc option for shutdown: suppress banner */ 94 if (geteuid() == 0) 95 nobanner = 1; 96 break; 97 case 'g': 98 g = (struct wallgroup *)malloc(sizeof *g); 99 g->next = grouplist; 100 g->name = optarg; 101 g->gid = -1; 102 grouplist = g; 103 break; 104 case '?': 105 default: 106 usage(); 107 } 108 argc -= optind; 109 argv += optind; 110 if (argc > 1) 111 usage(); 112 113 for (g = grouplist; g; g = g->next) { 114 grp = getgrnam(g->name); 115 if (grp != NULL) 116 g->gid = grp->gr_gid; 117 else 118 warnx("%s: no such group", g->name); 119 } 120 121 makemsg(*argv); 122 123 iov.iov_base = mbuf; 124 iov.iov_len = mbufsize; 125 126 getutentries(NULL, &ep); 127 /* NOSTRICT */ 128 for (; ep; ep = ep->next) { 129 if (grouplist) { 130 ingroup = 0; 131 pw = getpwnam(ep->name); 132 if (!pw) 133 continue; 134 for (g = grouplist; g && ingroup == 0; g = g->next) { 135 if (g->gid == (gid_t)-1) 136 continue; 137 if (g->gid == pw->pw_gid) 138 ingroup = 1; 139 else if ((grp = getgrgid(g->gid)) != NULL) { 140 for (np = grp->gr_mem; *np; np++) { 141 if (strcmp(*np, ep->name) == 0) { 142 ingroup = 1; 143 break; 144 } 145 } 146 } 147 } 148 if (ingroup == 0) 149 continue; 150 } 151 /* skip [xgk]dm/xserver entries (":0", ":1", etc.) */ 152 if (ep->line[0] == ':' && isdigit((unsigned char)ep->line[1])) 153 continue; 154 155 if ((p = ttymsg(&iov, 1, ep->line, 60*5)) != NULL) 156 warnx("%s", p); 157 } 158 exit(0); 159 } 160 161 static void 162 usage(void) 163 { 164 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 165 exit(1); 166 } 167 168 void 169 makemsg(char *fname) 170 { 171 int cnt; 172 unsigned char ch; 173 struct tm *lt; 174 struct passwd *pw; 175 struct stat sbuf; 176 time_t now; 177 FILE *fp; 178 int fd; 179 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[MAXPATHLEN]; 180 const char *tty; 181 const char *whom; 182 gid_t egid; 183 184 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 185 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 186 err(1, "can't open temporary file"); 187 (void)unlink(tmpname); 188 189 if (!nobanner) { 190 tty = ttyname(STDERR_FILENO); 191 if (tty == NULL) 192 tty = "no tty"; 193 194 if (!(whom = getlogin())) 195 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 196 (void)gethostname(hostname, sizeof(hostname)); 197 (void)time(&now); 198 lt = localtime(&now); 199 200 /* 201 * all this stuff is to blank out a square for the message; 202 * we wrap message lines at column 79, not 80, because some 203 * terminals wrap after 79, some do not, and we can't tell. 204 * Which means that we may leave a non-blank character 205 * in column 80, but that can't be helped. 206 */ 207 (void)fprintf(fp, "\r%79s\r\n", " "); 208 (void)snprintf(lbuf, sizeof(lbuf), 209 "Broadcast Message from %s@%s", 210 whom, hostname); 211 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 212 (void)snprintf(lbuf, sizeof(lbuf), 213 " (%s) at %d:%02d %s...", tty, 214 lt->tm_hour, lt->tm_min, lt->tm_zone); 215 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 216 } 217 (void)fprintf(fp, "%79s\r\n", " "); 218 219 if (fname) { 220 egid = getegid(); 221 setegid(getgid()); 222 if (freopen(fname, "r", stdin) == NULL) 223 err(1, "can't read %s", fname); 224 setegid(egid); 225 } 226 while (fgets(lbuf, sizeof(lbuf), stdin)) 227 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 228 if (ch == '\r') { 229 cnt = 0; 230 } else if (cnt == 79 || ch == '\n') { 231 for (; cnt < 79; ++cnt) 232 putc(' ', fp); 233 putc('\r', fp); 234 putc('\n', fp); 235 cnt = 0; 236 } else if (((ch & 0x80) && ch < 0xA0) || 237 /* disable upper controls */ 238 (!isprint(ch) && !isspace(ch) && 239 ch != '\a' && ch != '\b') 240 ) { 241 if (ch & 0x80) { 242 ch &= 0x7F; 243 putc('M', fp); 244 if (++cnt == 79) { 245 putc('\r', fp); 246 putc('\n', fp); 247 cnt = 0; 248 } 249 putc('-', fp); 250 if (++cnt == 79) { 251 putc('\r', fp); 252 putc('\n', fp); 253 cnt = 0; 254 } 255 } 256 if (iscntrl(ch)) { 257 ch ^= 040; 258 putc('^', fp); 259 if (++cnt == 79) { 260 putc('\r', fp); 261 putc('\n', fp); 262 cnt = 0; 263 } 264 } 265 putc(ch, fp); 266 } else { 267 putc(ch, fp); 268 } 269 } 270 (void)fprintf(fp, "%79s\r\n", " "); 271 rewind(fp); 272 273 if (fstat(fd, &sbuf)) 274 err(1, "can't stat temporary file"); 275 mbufsize = sbuf.st_size; 276 if (!(mbuf = malloc((u_int)mbufsize))) 277 err(1, "out of memory"); 278 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 279 err(1, "can't read temporary file"); 280 (void)close(fd); 281 } 282