19b50d902SRodney W. Grimes /* 29b50d902SRodney W. Grimes * Copyright (c) 1989, 1993 39b50d902SRodney W. Grimes * The Regents of the University of California. All rights reserved. 49b50d902SRodney W. Grimes * 59b50d902SRodney W. Grimes * Redistribution and use in source and binary forms, with or without 69b50d902SRodney W. Grimes * modification, are permitted provided that the following conditions 79b50d902SRodney W. Grimes * are met: 89b50d902SRodney W. Grimes * 1. Redistributions of source code must retain the above copyright 99b50d902SRodney W. Grimes * notice, this list of conditions and the following disclaimer. 109b50d902SRodney W. Grimes * 2. Redistributions in binary form must reproduce the above copyright 119b50d902SRodney W. Grimes * notice, this list of conditions and the following disclaimer in the 129b50d902SRodney W. Grimes * documentation and/or other materials provided with the distribution. 139b50d902SRodney W. Grimes * 3. All advertising materials mentioning features or use of this software 149b50d902SRodney W. Grimes * must display the following acknowledgement: 159b50d902SRodney W. Grimes * This product includes software developed by the University of 169b50d902SRodney W. Grimes * California, Berkeley and its contributors. 179b50d902SRodney W. Grimes * 4. Neither the name of the University nor the names of its contributors 189b50d902SRodney W. Grimes * may be used to endorse or promote products derived from this software 199b50d902SRodney W. Grimes * without specific prior written permission. 209b50d902SRodney W. Grimes * 219b50d902SRodney W. Grimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 229b50d902SRodney W. Grimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 239b50d902SRodney W. Grimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 249b50d902SRodney W. Grimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 259b50d902SRodney W. Grimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 269b50d902SRodney W. Grimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 279b50d902SRodney W. Grimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 289b50d902SRodney W. Grimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 299b50d902SRodney W. Grimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 309b50d902SRodney W. Grimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 319b50d902SRodney W. Grimes * SUCH DAMAGE. 329b50d902SRodney W. Grimes */ 339b50d902SRodney W. Grimes 349b50d902SRodney W. Grimes #ifndef lint 35a31bd3d6SPhilippe Charnier #if 0 369b50d902SRodney W. Grimes static char sccsid[] = "@(#)ttymsg.c 8.2 (Berkeley) 11/16/93"; 37a31bd3d6SPhilippe Charnier #endif 38a31bd3d6SPhilippe Charnier static const char rcsid[] = 39c3aac50fSPeter Wemm "$FreeBSD$"; 409b50d902SRodney W. Grimes #endif /* not lint */ 419b50d902SRodney W. Grimes 429b50d902SRodney W. Grimes #include <sys/types.h> 439b50d902SRodney W. Grimes #include <sys/uio.h> 449b50d902SRodney W. Grimes #include <dirent.h> 459b50d902SRodney W. Grimes #include <errno.h> 46a31bd3d6SPhilippe Charnier #include <fcntl.h> 479b50d902SRodney W. Grimes #include <paths.h> 48a31bd3d6SPhilippe Charnier #include <signal.h> 499b50d902SRodney W. Grimes #include <stdio.h> 509b50d902SRodney W. Grimes #include <string.h> 519b50d902SRodney W. Grimes #include <stdlib.h> 52a31bd3d6SPhilippe Charnier #include <unistd.h> 539b50d902SRodney W. Grimes 54728d043eSDima Dorfman #include "ttymsg.h" 55728d043eSDima Dorfman 569b50d902SRodney W. Grimes /* 579b50d902SRodney W. Grimes * Display the contents of a uio structure on a terminal. Used by wall(1), 589b50d902SRodney W. Grimes * syslogd(8), and talkd(8). Forks and finishes in child if write would block, 599b50d902SRodney W. Grimes * waiting up to tmout seconds. Returns pointer to error string on unexpected 609b50d902SRodney W. Grimes * error; string is not newline-terminated. Various "normal" errors are 619b50d902SRodney W. Grimes * ignored (exclusive-use, lack of permission, etc.). 629b50d902SRodney W. Grimes */ 63728d043eSDima Dorfman const char * 646a20d55aSWarner Losh ttymsg(struct iovec *iov, int iovcnt, const char *line, int tmout) 659b50d902SRodney W. Grimes { 666a20d55aSWarner Losh struct iovec localiov[7]; 67728d043eSDima Dorfman ssize_t left, wret; 68728d043eSDima Dorfman int cnt, fd; 699b50d902SRodney W. Grimes static char device[MAXNAMLEN] = _PATH_DEV; 709b50d902SRodney W. Grimes static char errbuf[1024]; 716a20d55aSWarner Losh int forked; 729b50d902SRodney W. Grimes 736a20d55aSWarner Losh forked = 0; 74728d043eSDima Dorfman if (iovcnt > (int)(sizeof(localiov) / sizeof(localiov[0]))) 759b50d902SRodney W. Grimes return ("too many iov's (change code in wall/ttymsg.c)"); 769b50d902SRodney W. Grimes 7792992eceSAndrey A. Chernov strlcpy(device + sizeof(_PATH_DEV) - 1, line, sizeof(device)); 789b50d902SRodney W. Grimes if (strchr(device + sizeof(_PATH_DEV) - 1, '/')) { 799b50d902SRodney W. Grimes /* A slash is an attempt to break security... */ 806a20d55aSWarner Losh (void) snprintf(errbuf, sizeof(errbuf), 816a20d55aSWarner Losh "Too many '/' in \"%s\"", device); 829b50d902SRodney W. Grimes return (errbuf); 839b50d902SRodney W. Grimes } 849b50d902SRodney W. Grimes 859b50d902SRodney W. Grimes /* 869b50d902SRodney W. Grimes * open will fail on slip lines or exclusive-use lines 879b50d902SRodney W. Grimes * if not running as root; not an error. 889b50d902SRodney W. Grimes */ 899b50d902SRodney W. Grimes if ((fd = open(device, O_WRONLY|O_NONBLOCK, 0)) < 0) { 909b50d902SRodney W. Grimes if (errno == EBUSY || errno == EACCES) 919b50d902SRodney W. Grimes return (NULL); 926a20d55aSWarner Losh (void) snprintf(errbuf, sizeof(errbuf), "%s: %s", device, 936a20d55aSWarner Losh strerror(errno)); 949b50d902SRodney W. Grimes return (errbuf); 959b50d902SRodney W. Grimes } 969b50d902SRodney W. Grimes 97728d043eSDima Dorfman for (cnt = 0, left = 0; cnt < iovcnt; ++cnt) 989b50d902SRodney W. Grimes left += iov[cnt].iov_len; 999b50d902SRodney W. Grimes 1009b50d902SRodney W. Grimes for (;;) { 1019b50d902SRodney W. Grimes wret = writev(fd, iov, iovcnt); 1029b50d902SRodney W. Grimes if (wret >= left) 1039b50d902SRodney W. Grimes break; 1049b50d902SRodney W. Grimes if (wret >= 0) { 1059b50d902SRodney W. Grimes left -= wret; 1069b50d902SRodney W. Grimes if (iov != localiov) { 1079b50d902SRodney W. Grimes bcopy(iov, localiov, 1089b50d902SRodney W. Grimes iovcnt * sizeof(struct iovec)); 1099b50d902SRodney W. Grimes iov = localiov; 1109b50d902SRodney W. Grimes } 111728d043eSDima Dorfman for (cnt = 0; (size_t)wret >= iov->iov_len; ++cnt) { 1129b50d902SRodney W. Grimes wret -= iov->iov_len; 1139b50d902SRodney W. Grimes ++iov; 1149b50d902SRodney W. Grimes --iovcnt; 1159b50d902SRodney W. Grimes } 1169b50d902SRodney W. Grimes if (wret) { 1179b50d902SRodney W. Grimes iov->iov_base += wret; 1189b50d902SRodney W. Grimes iov->iov_len -= wret; 1199b50d902SRodney W. Grimes } 1209b50d902SRodney W. Grimes continue; 1219b50d902SRodney W. Grimes } 1229b50d902SRodney W. Grimes if (errno == EWOULDBLOCK) { 1237111b0acSGuy Helmer int cpid; 1249b50d902SRodney W. Grimes 1259b50d902SRodney W. Grimes if (forked) { 1269b50d902SRodney W. Grimes (void) close(fd); 1279b50d902SRodney W. Grimes _exit(1); 1289b50d902SRodney W. Grimes } 1299b50d902SRodney W. Grimes cpid = fork(); 1309b50d902SRodney W. Grimes if (cpid < 0) { 1319b50d902SRodney W. Grimes (void) snprintf(errbuf, sizeof(errbuf), 1329b50d902SRodney W. Grimes "fork: %s", strerror(errno)); 1339b50d902SRodney W. Grimes (void) close(fd); 1349b50d902SRodney W. Grimes return (errbuf); 1359b50d902SRodney W. Grimes } 1369b50d902SRodney W. Grimes if (cpid) { /* parent */ 1379b50d902SRodney W. Grimes (void) close(fd); 1389b50d902SRodney W. Grimes return (NULL); 1399b50d902SRodney W. Grimes } 1409b50d902SRodney W. Grimes forked++; 1419b50d902SRodney W. Grimes /* wait at most tmout seconds */ 1429b50d902SRodney W. Grimes (void) signal(SIGALRM, SIG_DFL); 1439b50d902SRodney W. Grimes (void) signal(SIGTERM, SIG_DFL); /* XXX */ 1449b50d902SRodney W. Grimes (void) sigsetmask(0); 1459b50d902SRodney W. Grimes (void) alarm((u_int)tmout); 1467111b0acSGuy Helmer (void) fcntl(fd, F_SETFL, 0); /* clear O_NONBLOCK */ 1479b50d902SRodney W. Grimes continue; 1489b50d902SRodney W. Grimes } 1499b50d902SRodney W. Grimes /* 1509b50d902SRodney W. Grimes * We get ENODEV on a slip line if we're running as root, 1519b50d902SRodney W. Grimes * and EIO if the line just went away. 1529b50d902SRodney W. Grimes */ 1539b50d902SRodney W. Grimes if (errno == ENODEV || errno == EIO) 1549b50d902SRodney W. Grimes break; 1559b50d902SRodney W. Grimes (void) close(fd); 1569b50d902SRodney W. Grimes if (forked) 1579b50d902SRodney W. Grimes _exit(1); 1589b50d902SRodney W. Grimes (void) snprintf(errbuf, sizeof(errbuf), 1599b50d902SRodney W. Grimes "%s: %s", device, strerror(errno)); 1609b50d902SRodney W. Grimes return (errbuf); 1619b50d902SRodney W. Grimes } 1629b50d902SRodney W. Grimes 1639b50d902SRodney W. Grimes (void) close(fd); 1649b50d902SRodney W. Grimes if (forked) 1659b50d902SRodney W. Grimes _exit(0); 1669b50d902SRodney W. Grimes return (NULL); 1679b50d902SRodney W. Grimes } 168