Home | History | Annotate | Line # | Download | only in mail.local
mail.local.c revision 1.20 
      1 /*	$NetBSD: mail.local.c,v 1.20 2002/05/26 00:02:08 wiz Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1990, 1993, 1994
      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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 __COPYRIGHT("@(#) Copyright (c) 1990, 1993, 1994\n\
     39 	The Regents of the University of California.  All rights reserved.\n");
     40 #if 0
     41 static char sccsid[] = "@(#)mail.local.c	8.22 (Berkeley) 6/21/95";
     42 #else
     43 __RCSID("$NetBSD: mail.local.c,v 1.20 2002/05/26 00:02:08 wiz Exp $");
     44 #endif
     45 #endif /* not lint */
     46 
     47 #include <sys/param.h>
     48 #include <sys/stat.h>
     49 #include <sys/socket.h>
     50 
     51 #include <netinet/in.h>
     52 
     53 #include <errno.h>
     54 #include <fcntl.h>
     55 #include <pwd.h>
     56 #include <netdb.h>
     57 #include <stdarg.h>
     58 #include <stdio.h>
     59 #include <stdlib.h>
     60 #include <string.h>
     61 #include <syslog.h>
     62 #include <time.h>
     63 #include <unistd.h>
     64 
     65 #include "pathnames.h"
     66 
     67 #define	FATAL		1
     68 #define	NOTFATAL	0
     69 
     70 int	deliver __P((int, char *, int));
     71 void	err __P((int, const char *, ...))
     72      __attribute__((__format__(__printf__, 2, 3)));
     73 void	notifybiff __P((char *));
     74 int	store __P((const char *));
     75 void	usage __P((void));
     76 int	main __P((int, char **));
     77 
     78 int
     79 main(argc, argv)
     80 	int argc;
     81 	char **argv;
     82 {
     83 	struct passwd *pw;
     84 	int ch, fd, eval, lockfile = 0;
     85 	uid_t uid;
     86 	const char *from;
     87 
     88 	/* use a reasonable umask */
     89 	(void) umask(0077);
     90 
     91 	openlog("mail.local", LOG_PERROR, LOG_MAIL);
     92 
     93 	from = NULL;
     94 	while ((ch = getopt(argc, argv, "ldf:r:")) != -1)
     95 		switch (ch) {
     96 		case 'd':		/* backward compatible */
     97 			break;
     98 		case 'f':
     99 		case 'r':		/* backward compatible */
    100 			if (from)
    101 				err(FATAL, "multiple -f options");
    102 			from = optarg;
    103 			break;
    104 		case 'l':
    105 			lockfile++;
    106 			break;
    107 		case '?':
    108 		default:
    109 			usage();
    110 		}
    111 	argc -= optind;
    112 	argv += optind;
    113 
    114 	if (!*argv)
    115 		usage();
    116 
    117 	/*
    118 	 * If from not specified, use the name from getlogin() if the
    119 	 * uid matches, otherwise, use the name from the password file
    120 	 * corresponding to the uid.
    121 	 */
    122 	uid = getuid();
    123 	if (!from && (!(from = getlogin()) ||
    124 	    !(pw = getpwnam(from)) || pw->pw_uid != uid))
    125 		from = (pw = getpwuid(uid)) ? pw->pw_name : "???";
    126 
    127 	fd = store(from);
    128 	for (eval = 0; *argv; ++argv)
    129 		eval |= deliver(fd, *argv, lockfile);
    130 	exit (eval);
    131 }
    132 
    133 int
    134 store(from)
    135 	const char *from;
    136 {
    137 	FILE *fp = NULL;	/* XXX gcc */
    138 	time_t tval;
    139 	int fd, eline;
    140 	char *tn, line[2048];
    141 
    142 	tn = strdup(_PATH_LOCTMP);
    143 	if ((fd = mkstemp(tn)) == -1 || !(fp = fdopen(fd, "w+")))
    144 		err(FATAL, "unable to open temporary file");
    145 	(void)unlink(tn);
    146 	free(tn);
    147 
    148 	(void)time(&tval);
    149 	(void)fprintf(fp, "From %s %s", from, ctime(&tval));
    150 
    151 	line[0] = '\0';
    152 	for (eline = 1; fgets(line, sizeof(line), stdin);) {
    153 		if (line[0] == '\n')
    154 			eline = 1;
    155 		else {
    156 			if (eline && line[0] == 'F' && !memcmp(line, "From ", 5))
    157 				(void)putc('>', fp);
    158 			eline = 0;
    159 		}
    160 		(void)fprintf(fp, "%s", line);
    161 		if (ferror(fp))
    162 			break;
    163 	}
    164 
    165 	/* If message not newline terminated, need an extra. */
    166 	if (!index(line, '\n'))
    167 		(void)putc('\n', fp);
    168 	/* Output a newline; note, empty messages are allowed. */
    169 	(void)putc('\n', fp);
    170 
    171 	(void)fflush(fp);
    172 	if (ferror(fp))
    173 		err(FATAL, "temporary file write error");
    174 	return(fd);
    175 }
    176 
    177 int
    178 deliver(fd, name, lockfile)
    179 	int fd;
    180 	char *name;
    181 	int lockfile;
    182 {
    183 	struct stat sb;
    184 	struct passwd *pw;
    185 	int created, mbfd, nr, nw, off, rval=0, lfd=-1;
    186 	char biffmsg[100], buf[8*1024], path[MAXPATHLEN], lpath[MAXPATHLEN];
    187 	off_t curoff;
    188 
    189 	/*
    190 	 * Disallow delivery to unknown names -- special mailboxes can be
    191 	 * handled in the sendmail aliases file.
    192 	 */
    193 	if (!(pw = getpwnam(name))) {
    194 		err(NOTFATAL, "unknown name: %s", name);
    195 		return(1);
    196 	}
    197 
    198 	(void)snprintf(path, sizeof path, "%s/%s", _PATH_MAILDIR, name);
    199 
    200 	if (lockfile) {
    201 		(void)snprintf(lpath, sizeof lpath, "%s/%s.lock",
    202 		    _PATH_MAILDIR, name);
    203 
    204 		if((lfd = open(lpath, O_CREAT|O_WRONLY|O_EXCL,
    205 		    S_IRUSR|S_IWUSR)) < 0) {
    206 			err(NOTFATAL, "%s: %s", lpath, strerror(errno));
    207 			return(1);
    208 		}
    209 	}
    210 
    211 	if (!(created = lstat(path, &sb)) &&
    212 	    (sb.st_nlink != 1 || S_ISLNK(sb.st_mode))) {
    213 		err(NOTFATAL, "%s: linked file", path);
    214 		return(1);
    215 	}
    216 	if ((mbfd = open(path, O_APPEND|O_WRONLY|O_EXLOCK,
    217 	    S_IRUSR|S_IWUSR)) < 0) {
    218 		if ((mbfd = open(path, O_APPEND|O_CREAT|O_WRONLY|O_EXLOCK,
    219 		    S_IRUSR|S_IWUSR)) < 0) {
    220 			err(NOTFATAL, "%s: %s", path, strerror(errno));
    221 			return(1);
    222 		}
    223 	}
    224 
    225 	curoff = lseek(mbfd, 0, SEEK_END);
    226 	(void)snprintf(biffmsg, sizeof biffmsg, "%s@%lld\n", name,
    227 	    (long long)curoff);
    228 	if (lseek(fd, 0, SEEK_SET) == (off_t)-1) {
    229 		err(FATAL, "temporary file: %s", strerror(errno));
    230 		rval = 1;
    231 		goto bad;
    232 	}
    233 
    234 	while ((nr = read(fd, buf, sizeof(buf))) > 0)
    235 		for (off = 0; off < nr;  off += nw)
    236 			if ((nw = write(mbfd, buf + off, nr - off)) < 0) {
    237 				err(NOTFATAL, "%s: %s", path, strerror(errno));
    238 				goto trunc;
    239 			}
    240 	if (nr < 0) {
    241 		err(FATAL, "temporary file: %s", strerror(errno));
    242 trunc:		(void)ftruncate(mbfd, curoff);
    243 		rval = 1;
    244 	}
    245 
    246 	/*
    247 	 * Set the owner and group.  Historically, binmail repeated this at
    248 	 * each mail delivery.  We no longer do this, assuming that if the
    249 	 * ownership or permissions were changed there was a reason for doing
    250 	 * so.
    251 	 */
    252 bad:
    253 	if (lockfile) {
    254 		if (lfd >= 0) {
    255 			unlink(lpath);
    256 			close(lfd);
    257 		}
    258 	}
    259 	if (created)
    260 		(void)fchown(mbfd, pw->pw_uid, pw->pw_gid);
    261 
    262 	(void)fsync(mbfd);		/* Don't wait for update. */
    263 	(void)close(mbfd);		/* Implicit unlock. */
    264 
    265 	if (!rval)
    266 		notifybiff(biffmsg);
    267 	return(rval);
    268 }
    269 
    270 void
    271 notifybiff(msg)
    272 	char *msg;
    273 {
    274 	static struct sockaddr_in addr;
    275 	static int f = -1;
    276 	struct hostent *hp;
    277 	struct servent *sp;
    278 	int len;
    279 
    280 	if (!addr.sin_family) {
    281 		/* Be silent if biff service not available. */
    282 		if (!(sp = getservbyname("biff", "udp")))
    283 			return;
    284 		if (!(hp = gethostbyname("localhost"))) {
    285 			err(NOTFATAL, "localhost: %s", strerror(errno));
    286 			return;
    287 		}
    288 		addr.sin_len = sizeof(struct sockaddr_in);
    289 		addr.sin_family = hp->h_addrtype;
    290 		addr.sin_port = sp->s_port;
    291 		memcpy(&addr.sin_addr, hp->h_addr, hp->h_length);
    292 	}
    293 	if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
    294 		err(NOTFATAL, "socket: %s", strerror(errno));
    295 		return;
    296 	}
    297 	len = strlen(msg) + 1;
    298 	if (sendto(f, msg, len, 0, (struct sockaddr *)&addr, sizeof(addr))
    299 	    != len)
    300 		err(NOTFATAL, "sendto biff: %s", strerror(errno));
    301 }
    302 
    303 void
    304 usage()
    305 {
    306 	err(FATAL, "usage: mail.local [-l] [-f from] user ...");
    307 }
    308 
    309 void
    310 err(int isfatal, const char *fmt, ...)
    311 {
    312 	va_list ap;
    313 
    314 	va_start(ap, fmt);
    315 	vsyslog(LOG_ERR, fmt, ap);
    316 	va_end(ap);
    317 	if (isfatal)
    318 		exit(1);
    319 }
    320