1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988, 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * This program is not related to David Wall, whose Stanford Ph.D. thesis 34 * is entitled "Mechanisms for Broadcast and Selective Broadcast". 35 */ 36 37 #include <sys/param.h> 38 #include <sys/stat.h> 39 #include <sys/uio.h> 40 41 #include <ctype.h> 42 #include <err.h> 43 #include <grp.h> 44 #include <locale.h> 45 #include <paths.h> 46 #include <pwd.h> 47 #include <stdio.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <time.h> 51 #include <unistd.h> 52 #include <utmpx.h> 53 #include <wchar.h> 54 #include <wctype.h> 55 56 #include "ttymsg.h" 57 58 static void makemsg(char *); 59 static void usage(void) __dead2; 60 61 static struct wallgroup { 62 struct wallgroup *next; 63 char *name; 64 gid_t gid; 65 } *grouplist; 66 static int nobanner; 67 static int mbufsize; 68 static char *mbuf; 69 70 static int 71 ttystat(char *line) 72 { 73 struct stat sb; 74 char ttybuf[MAXPATHLEN]; 75 76 (void)snprintf(ttybuf, sizeof(ttybuf), "%s%s", _PATH_DEV, line); 77 if (stat(ttybuf, &sb) == 0) { 78 return (0); 79 } else 80 return (-1); 81 } 82 83 int 84 main(int argc, char *argv[]) 85 { 86 struct iovec iov; 87 struct utmpx *utmp; 88 int ch; 89 int ingroup; 90 struct wallgroup *g; 91 struct group *grp; 92 char **np; 93 const char *p; 94 struct passwd *pw; 95 96 (void)setlocale(LC_CTYPE, ""); 97 98 while ((ch = getopt(argc, argv, "g:n")) != -1) 99 switch (ch) { 100 case 'n': 101 /* undoc option for shutdown: suppress banner */ 102 if (geteuid() == 0) 103 nobanner = 1; 104 break; 105 case 'g': 106 g = (struct wallgroup *)malloc(sizeof *g); 107 g->next = grouplist; 108 g->name = optarg; 109 g->gid = -1; 110 grouplist = g; 111 break; 112 case '?': 113 default: 114 usage(); 115 } 116 argc -= optind; 117 argv += optind; 118 if (argc > 1) 119 usage(); 120 121 for (g = grouplist; g; g = g->next) { 122 grp = getgrnam(g->name); 123 if (grp != NULL) 124 g->gid = grp->gr_gid; 125 else 126 warnx("%s: no such group", g->name); 127 } 128 129 makemsg(*argv); 130 131 iov.iov_base = mbuf; 132 iov.iov_len = mbufsize; 133 /* NOSTRICT */ 134 while ((utmp = getutxent()) != NULL) { 135 if (utmp->ut_type != USER_PROCESS) 136 continue; 137 if (ttystat(utmp->ut_line) != 0) 138 continue; 139 if (grouplist) { 140 ingroup = 0; 141 pw = getpwnam(utmp->ut_user); 142 if (!pw) 143 continue; 144 for (g = grouplist; g && ingroup == 0; g = g->next) { 145 if (g->gid == (gid_t)-1) 146 continue; 147 if (g->gid == pw->pw_gid) 148 ingroup = 1; 149 else if ((grp = getgrgid(g->gid)) != NULL) { 150 for (np = grp->gr_mem; *np; np++) { 151 if (strcmp(*np, utmp->ut_user) == 0) { 152 ingroup = 1; 153 break; 154 } 155 } 156 } 157 } 158 if (ingroup == 0) 159 continue; 160 } 161 if ((p = ttymsg(&iov, 1, utmp->ut_line, 60*5)) != NULL) 162 warnx("%s", p); 163 } 164 exit(0); 165 } 166 167 static void 168 usage(void) 169 { 170 (void)fprintf(stderr, "usage: wall [-g group] [file]\n"); 171 exit(1); 172 } 173 174 void 175 makemsg(char *fname) 176 { 177 int cnt; 178 wchar_t ch; 179 struct tm *lt; 180 struct passwd *pw; 181 struct stat sbuf; 182 time_t now; 183 FILE *fp; 184 int fd; 185 char hostname[MAXHOSTNAMELEN], tmpname[64]; 186 wchar_t *p, *tmp, lbuf[256], codebuf[13]; 187 const char *tty; 188 const char *whom; 189 gid_t egid; 190 191 (void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP); 192 if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+"))) 193 err(1, "can't open temporary file"); 194 (void)unlink(tmpname); 195 196 if (!nobanner) { 197 tty = ttyname(STDERR_FILENO); 198 if (tty == NULL) 199 tty = "no tty"; 200 201 if (!(whom = getlogin())) 202 whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???"; 203 (void)gethostname(hostname, sizeof(hostname)); 204 (void)time(&now); 205 lt = localtime(&now); 206 207 /* 208 * all this stuff is to blank out a square for the message; 209 * we wrap message lines at column 79, not 80, because some 210 * terminals wrap after 79, some do not, and we can't tell. 211 * Which means that we may leave a non-blank character 212 * in column 80, but that can't be helped. 213 */ 214 (void)fwprintf(fp, L"\r%79s\r\n", " "); 215 (void)swprintf(lbuf, sizeof(lbuf)/sizeof(wchar_t), 216 L"Broadcast Message from %s@%s", 217 whom, hostname); 218 (void)fwprintf(fp, L"%-79.79S\007\007\r\n", lbuf); 219 (void)swprintf(lbuf, sizeof(lbuf)/sizeof(wchar_t), 220 L" (%s) at %d:%02d %s...", tty, 221 lt->tm_hour, lt->tm_min, lt->tm_zone); 222 (void)fwprintf(fp, L"%-79.79S\r\n", lbuf); 223 } 224 (void)fwprintf(fp, L"%79s\r\n", " "); 225 226 if (fname) { 227 egid = getegid(); 228 setegid(getgid()); 229 if (freopen(fname, "r", stdin) == NULL) 230 err(1, "can't read %s", fname); 231 if (setegid(egid) != 0) 232 err(1, "setegid failed"); 233 } 234 cnt = 0; 235 while (fgetws(lbuf, sizeof(lbuf)/sizeof(wchar_t), stdin)) { 236 for (p = lbuf; (ch = *p) != L'\0'; ++p, ++cnt) { 237 if (ch == L'\r') { 238 putwc(L'\r', fp); 239 cnt = 0; 240 continue; 241 } else if (ch == L'\n') { 242 for (; cnt < 79; ++cnt) 243 putwc(L' ', fp); 244 putwc(L'\r', fp); 245 putwc(L'\n', fp); 246 break; 247 } 248 if (cnt == 79) { 249 putwc(L'\r', fp); 250 putwc(L'\n', fp); 251 cnt = 0; 252 } 253 if (iswprint(ch) || iswspace(ch) || ch == L'\a' || ch == L'\b') { 254 putwc(ch, fp); 255 } else { 256 (void)swprintf(codebuf, sizeof(codebuf)/sizeof(wchar_t), L"<0x%X>", ch); 257 for (tmp = codebuf; *tmp != L'\0'; ++tmp) { 258 putwc(*tmp, fp); 259 if (++cnt == 79) { 260 putwc(L'\r', fp); 261 putwc(L'\n', fp); 262 cnt = 0; 263 } 264 } 265 --cnt; 266 } 267 } 268 } 269 (void)fwprintf(fp, L"%79s\r\n", " "); 270 rewind(fp); 271 272 if (fstat(fd, &sbuf)) 273 err(1, "can't stat temporary file"); 274 mbufsize = sbuf.st_size; 275 if (!(mbuf = malloc((u_int)mbufsize))) 276 err(1, "out of memory"); 277 if ((int)fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) 278 err(1, "can't read temporary file"); 279 fclose(fp); 280 } 281