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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#) Copyright (c) 1988, 1990, 1993 The Regents of the University of California. All rights reserved. 30 * @(#)wall.c 8.2 (Berkeley) 11/16/93 31 * $FreeBSD: src/usr.bin/wall/wall.c,v 1.13.2.6 2001/10/18 08:08:17 des Exp $ 32 * $DragonFly: src/usr.bin/wall/wall.c,v 1.4 2005/08/31 16:27:53 liamfoy Exp $ 33 */ 34 35 /* 36 * This program is not related to David Wall, whose Stanford Ph.D. thesis 37 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 38 */ 39 40 #include <sys/param.h> 41 #include <sys/stat.h> 42 #include <sys/uio.h> 43 44 #include <ctype.h> 45 #include <err.h> 46 #include <grp.h> 47 #include <locale.h> 48 #include <paths.h> 49 #include <pwd.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <time.h> 54 #include <unistd.h> 55 #include "utmpentry.h" 56 57 #include "ttymsg.h" 58 59 static void makemsg(char *); 60 static void usage(void); 61 62 struct wallgroup { 63 struct wallgroup *next; 64 char *name; 65 gid_t gid; 66 } *grouplist; 67 int nobanner; 68 int mbufsize; 69 char *mbuf; 70 71 int 72 main(int argc, char *argv[]) 73 { 74 struct iovec iov; 75 struct utmpentry *ep = NULL; /* avoid gcc warnings */ 76 int ch; 77 int ingroup; 78 struct wallgroup *g; 79 struct group *grp; 80 char **np; 81 const char *p; 82 struct passwd *pw; 83 84 (void)setlocale(LC_CTYPE, ""); 85 86 while ((ch = getopt(argc, argv, "g:n")) != -1) 87 switch (ch) { 88 case 'n': 89 /* undoc option for shutdown: suppress banner */ 90 if (geteuid() == 0) 91 nobanner = 1; 92 break; 93 case 'g': 94 g = (struct wallgroup *)malloc(sizeof *g); 95 g->next = grouplist; 96 g->name = optarg; 97 g->gid = -1; 98 grouplist = g; 99 break; 100 case '?': 101 default: 102 usage(); 103 } 104 argc -= optind; 105 argv += optind; 106 if (argc > 1) 107 usage(); 108 109 for (g = grouplist; g; g = g->next) { 110 grp = getgrnam(g->name); 111 if (grp != NULL) 112 g->gid = grp->gr_gid; 113 else 114 warnx("%s: no such group", g->name); 115 } 116 117 makemsg(*argv); 118 119 iov.iov_base = mbuf; 120 iov.iov_len = mbufsize; 121 122 getutentries(NULL, &ep); 123 /* NOSTRICT */ 124 for (; ep; ep = ep->next) { 125 if (grouplist) { 126 ingroup = 0; 127 pw = getpwnam(ep->name); 128 if (!pw) 129 continue; 130 for (g = grouplist; g && ingroup == 0; g = g->next) { 131 if (g->gid == (gid_t)-1) 132 continue; 133 if (g->gid == pw->pw_gid) 134 ingroup = 1; 135 else if ((grp = getgrgid(g->gid)) != NULL) { 136 for (np = grp->gr_mem; *np; np++) { 137 if (strcmp(*np, ep->name) == 0) { 138 ingroup = 1; 139 break; 140 } 141 } 142 } 143 } 144 if (ingroup == 0) 145 continue; 146 } 147 /* skip [xgk]dm/xserver entries (":0", ":1", etc.) */ 148 if (ep->line[0] == ':' && isdigit((unsigned char)ep->line[1])) 149 continue; 150 151 if ((p = ttymsg(&iov, 1, ep->line, 60*5)) != NULL) 152 warnx("%s", p); 153 } 154 exit(0); 155 } 156 157 static void 158 usage(void) 159 { 160 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 161 exit(1); 162 } 163 164 void 165 makemsg(char *fname) 166 { 167 int cnt; 168 unsigned char ch; 169 struct tm *lt; 170 struct passwd *pw; 171 struct stat sbuf; 172 time_t now; 173 FILE *fp; 174 int fd; 175 char *p, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[MAXPATHLEN]; 176 const char *tty; 177 const char *whom; 178 gid_t egid; 179 180 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 181 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 182 err(1, "can't open temporary file"); 183 (void)unlink(tmpname); 184 185 if (!nobanner) { 186 tty = ttyname(STDERR_FILENO); 187 if (tty == NULL) 188 tty = "no tty"; 189 190 if (!(whom = getlogin())) 191 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 192 (void)gethostname(hostname, sizeof(hostname)); 193 (void)time(&now); 194 lt = localtime(&now); 195 196 /* 197 * all this stuff is to blank out a square for the message; 198 * we wrap message lines at column 79, not 80, because some 199 * terminals wrap after 79, some do not, and we can't tell. 200 * Which means that we may leave a non-blank character 201 * in column 80, but that can't be helped. 202 */ 203 (void)fprintf(fp, "\r%79s\r\n", " "); 204 (void)snprintf(lbuf, sizeof(lbuf), 205 "Broadcast Message from %s@%s", 206 whom, hostname); 207 (void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf); 208 (void)snprintf(lbuf, sizeof(lbuf), 209 " (%s) at %d:%02d %s...", tty, 210 lt->tm_hour, lt->tm_min, lt->tm_zone); 211 (void)fprintf(fp, "%-79.79s\r\n", lbuf); 212 } 213 (void)fprintf(fp, "%79s\r\n", " "); 214 215 if (fname) { 216 egid = getegid(); 217 setegid(getgid()); 218 if (freopen(fname, "r", stdin) == NULL) 219 err(1, "can't read %s", fname); 220 setegid(egid); 221 } 222 while (fgets(lbuf, sizeof(lbuf), stdin)) 223 for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) { 224 if (ch == '\r') { 225 cnt = 0; 226 } else if (cnt == 79 || ch == '\n') { 227 for (; cnt < 79; ++cnt) 228 putc(' ', fp); 229 putc('\r', fp); 230 putc('\n', fp); 231 cnt = 0; 232 } else if (((ch & 0x80) && ch < 0xA0) || 233 /* disable upper controls */ 234 (!isprint(ch) && !isspace(ch) && 235 ch != '\a' && ch != '\b') 236 ) { 237 if (ch & 0x80) { 238 ch &= 0x7F; 239 putc('M', fp); 240 if (++cnt == 79) { 241 putc('\r', fp); 242 putc('\n', fp); 243 cnt = 0; 244 } 245 putc('-', fp); 246 if (++cnt == 79) { 247 putc('\r', fp); 248 putc('\n', fp); 249 cnt = 0; 250 } 251 } 252 if (iscntrl(ch)) { 253 ch ^= 040; 254 putc('^', fp); 255 if (++cnt == 79) { 256 putc('\r', fp); 257 putc('\n', fp); 258 cnt = 0; 259 } 260 } 261 putc(ch, fp); 262 } else { 263 putc(ch, fp); 264 } 265 } 266 (void)fprintf(fp, "%79s\r\n", " "); 267 rewind(fp); 268 269 if (fstat(fd, &sbuf)) 270 err(1, "can't stat temporary file"); 271 mbufsize = sbuf.st_size; 272 if (!(mbuf = malloc((u_int)mbufsize))) 273 err(1, "out of memory"); 274 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 275 err(1, "can't read temporary file"); 276 (void)close(fd); 277 } 278