mail.local.c

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	fprintf(stderr, "before writing: euid = %d\n", geteuid());
#endif /* DEBUG */
#ifdef CONTENTLENGTH
	headerbytes = (BodyLength >= 0) ? HeaderLength : -1 ;
	for (;;)
	{
		if (headerbytes == 0)
		{
			snprintf(buf, sizeof buf, "%s", ContentHdr);
			nr = strlen(buf);
			headerbytes = -1;
			readamount = 0;
		}
		else if (headerbytes > sizeof(buf) || headerbytes < 0)
			readamount = sizeof(buf);
		else
			readamount = headerbytes;
		if (readamount != 0)
			nr = read(fd, buf, readamount);
		if (nr <= 0)
			break;
		if (headerbytes > 0)
			headerbytes -= nr ;

#else /* CONTENTLENGTH */
	while ((nr = read(fd, buf, sizeof(buf))) > 0)
	{
#endif /* CONTENTLENGTH */
		for (off = 0; off < nr; off += nw)
		{
			if ((nw = write(mbfd, buf + off, nr - off)) < 0)
			{
#ifdef EDQUOT
				if (errno == EDQUOT && bouncequota)
					mailerr("552 5.2.2", "%s: %s",
						path, errstring(errno));
				else
#endif /* EDQUOT */
				mailerr("450 4.2.0", "%s: %s",
					path, errstring(errno));
				goto err3;
			}
		}
	}
	if (nr < 0)
	{
		mailerr("450 4.2.0", "temporary file: %s",
			errstring(errno));
		goto err3;
	}

	/* Flush to disk, don't wait for update. */
	if (fsync(mbfd) < 0)
	{
		mailerr("450 4.2.0", "%s: %s", path, errstring(errno));
err3:
		if (setreuid(0, 0) < 0)
		{
#if 0
			/* already printed an error above for this recipient */
			(void) e_to_sys(errno);
			mailerr("450 4.2.0", "setreuid(0, 0): %s",
				errstring(errno));
#endif /* 0 */
		}
#ifdef DEBUG
		fprintf(stderr, "reset euid = %d\n", geteuid());
#endif /* DEBUG */
		(void) ftruncate(mbfd, curoff);
err1:		if (mbfd >= 0)
			(void) close(mbfd);
err0:		unlockmbox();
		return;
	}

	/* Close and check -- NFS doesn't write until the close. */
	if (close(mbfd))
	{
#ifdef EDQUOT
		if (errno == EDQUOT && bouncequota)
			mailerr("552 5.2.2", "%s: %s", path, errstring(errno));
		else
#endif /* EDQUOT */
		mailerr("450 4.2.0", "%s: %s", path, errstring(errno));
		(void) truncate(path, curoff);
	}
	else
		notifybiff(biffmsg);

	if (setreuid(0, 0) < 0)
	{
		mailerr("450 4.2.0", "setreuid(0, 0): %s",
			errstring(errno));
		goto err0;
	}
#ifdef DEBUG
	fprintf(stderr, "reset euid = %d\n", geteuid());
#endif /* DEBUG */
	unlockmbox();
	if (LMTPMode)
		printf("250 2.1.5 %s OK\r\n", name);
}

/*
**  user.lock files are necessary for compatibility with other
**  systems, e.g., when the mail spool file is NFS exported.
**  Alas, mailbox locking is more than just a local matter.
**  EPA 11/94.
*/

bool	Locked = FALSE;

#ifdef MAILLOCK
int
lockmbox(name)
	char *name;
{
	int r = 0;

	if (Locked)
		return 0;
	if ((r = maillock(name, 15)) == L_SUCCESS)
	{
		Locked = TRUE;
		return 0;
	}
	switch (r)
	{
	  case L_TMPLOCK:	/* Can't create tmp file */
	  case L_TMPWRITE:	/* Can't write pid into lockfile */
	  case L_MAXTRYS:	/* Failed after retrycnt attempts */
		errno = 0;
		r = EX_TEMPFAIL;
		break;
	  case L_ERROR:		/* Check errno for reason */
		r = errno;
		break;
	  default:		/* other permanent errors */
		errno = 0;
		r = EX_UNAVAILABLE;
		break;
	}
	return r;
}

void
unlockmbox()
{
	if (Locked)
		mailunlock();
	Locked = FALSE;
}
#else /* MAILLOCK */

char	LockName[MAXPATHLEN];

int
lockmbox(path)
	char *path;
{
	int statfailed = 0;
	time_t start;

	if (Locked)
		return 0;
	if (strlen(path) + 6 > sizeof LockName)
		return EX_SOFTWARE;
	(void) snprintf(LockName, sizeof LockName, "%s.lock", path);
	(void) time(&start);
	for (; ; sleep(5))
	{
		int fd;
		struct stat st;
		time_t now;

		/* global timeout */
		(void) time(&now);
		if (now > start + LOCKTO_GLOB)
		{
			errno = 0;
			return EX_TEMPFAIL;
		}
		fd = open(LockName, O_WRONLY|O_EXCL|O_CREAT, 0);
		if (fd >= 0)
		{
			/* defeat lock checking programs which test pid */
			(void) write(fd, "0", 2);
			Locked = TRUE;
			(void) close(fd);
			return 0;
		}
		if (stat(LockName, &st) < 0)
		{
			if (statfailed++ > 5)
			{
				errno = 0;
				return EX_TEMPFAIL;
			}
			continue;
		}
		statfailed = 0;
		(void) time(&now);
		if (now < st.st_ctime + LOCKTO_RM)
			continue;

		/* try to remove stale lockfile */
		if (unlink(LockName) < 0)
			return errno;
	}
}

void
unlockmbox()
{
	if (!Locked)
		return;
	(void) unlink(LockName);
	Locked = FALSE;
}
#endif /* MAILLOCK */

void
notifybiff(msg)
	char *msg;
{
	static bool initialized = FALSE;
	static int f = -1;
	struct hostent *hp;
	struct servent *sp;
	int len;
	static struct sockaddr_in addr;

	if (!initialized)
	{
		initialized = TRUE;

		/* Be silent if biff service not available. */
		if ((sp = getservbyname("biff", "udp")) == NULL ||
		    (hp = gethostbyname("localhost")) == NULL ||
		    hp->h_length != INADDRSZ)
			return;

		addr.sin_family = hp->h_addrtype;
		memcpy(&addr.sin_addr, hp->h_addr, INADDRSZ);
		addr.sin_port = sp->s_port;
	}

	/* No message, just return */
	if (msg == NULL)
		return;

	/* Couldn't initialize addr struct */
	if (addr.sin_family == AF_UNSPEC)
		return;

	if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
		return;
	len = strlen(msg) + 1;
	(void) sendto(f, msg, len, 0, (struct sockaddr *) &addr, sizeof(addr));
}

void
usage()
{
	ExitVal = EX_USAGE;
	mailerr(NULL, "usage: mail.local [-7] [-b] [-l] [-f from] user ...");
	exit(ExitVal);
}

void
#ifdef __STDC__
mailerr(const char *hdr, const char *fmt, ...)
#else /* __STDC__ */
mailerr(hdr, fmt, va_alist)
	const char *hdr;
	const char *fmt;
	va_dcl
#endif /* __STDC__ */
{
	va_list ap;

#ifdef __STDC__
	va_start(ap, fmt);
#else /* __STDC__ */
	va_start(ap);
#endif /* __STDC__ */
	if (LMTPMode)
	{
		if (hdr != NULL)
			printf("%s ", hdr);
		(void) vprintf(fmt, ap);
		(void) printf("\r\n");
	}
	else
	{
		(void) e_to_sys(errno);
		vwarn(fmt, ap);
	}
}

void
vwarn(fmt, ap)
	const char *fmt;
	_BSD_VA_LIST_ ap;
{
	/*
	**  Log the message to stderr.
	**
	**  Don't use LOG_PERROR as an openlog() flag to do this,
	**  it's not portable enough.
	*/

	if (ExitVal != EX_USAGE)
		(void) fprintf(stderr, "mail.local: ");
	(void) vfprintf(stderr, fmt, ap);
	(void) fprintf(stderr, "\n");

#if USE_VSYSLOG
	/* Log the message to syslog. */
	vsyslog(LOG_ERR, fmt, ap);
#else /* USE_VSYSLOG */
	{
		char fmtbuf[10240];

		(void) vsnprintf(fmtbuf, sizeof fmtbuf, fmt, ap);
		syslog(LOG_ERR, "%s", fmtbuf);
	}
#endif /* USE_VSYSLOG */
}

/*
 * e_to_sys --
 *	Guess which errno's are temporary.  Gag me.
 */
int
e_to_sys(num)
	int num;
{
	/* Temporary failures override hard errors. */
	if (ExitVal == EX_TEMPFAIL)
		return ExitVal;

	switch (num)		/* Hopefully temporary errors. */
	{
#ifdef EDQUOT
	  case EDQUOT:		/* Disc quota exceeded */
		if (bouncequota)
		{
			ExitVal = EX_UNAVAILABLE;
			break;
		}
		/* FALLTHROUGH */
#endif /* EDQUOT */
#ifdef EAGAIN
	  case EAGAIN:		/* Resource temporarily unavailable */
#endif /* EAGAIN */
#ifdef EBUSY
	  case EBUSY:		/* Device busy */
#endif /* EBUSY */
#ifdef EPROCLIM
	  case EPROCLIM:	/* Too many processes */
#endif /* EPROCLIM */
#ifdef EUSERS
	  case EUSERS:		/* Too many users */
#endif /* EUSERS */
#ifdef ECONNABORTED
	  case ECONNABORTED:	/* Software caused connection abort */
#endif /* ECONNABORTED */
#ifdef ECONNREFUSED
	  case ECONNREFUSED:	/* Connection refused */
#endif /* ECONNREFUSED */
#ifdef ECONNRESET
	  case ECONNRESET:	/* Connection reset by peer */
#endif /* ECONNRESET */
#ifdef EDEADLK
	  case EDEADLK:		/* Resource deadlock avoided */
#endif /* EDEADLK */
#ifdef EFBIG
	  case EFBIG:		/* File too large */
#endif /* EFBIG */
#ifdef EHOSTDOWN
	  case EHOSTDOWN:	/* Host is down */
#endif /* EHOSTDOWN */
#ifdef EHOSTUNREACH
	  case EHOSTUNREACH:	/* No route to host */
#endif /* EHOSTUNREACH */
#ifdef EMFILE
	  case EMFILE:		/* Too many open files */
#endif /* EMFILE */
#ifdef ENETDOWN
	  case ENETDOWN:	/* Network is down */
#endif /* ENETDOWN */
#ifdef ENETRESET
	  case ENETRESET:	/* Network dropped connection on reset */
#endif /* ENETRESET */
#ifdef ENETUNREACH
	  case ENETUNREACH:	/* Network is unreachable */
#endif /* ENETUNREACH */
#ifdef ENFILE
	  case ENFILE:		/* Too many open files in system */
#endif /* ENFILE */
#ifdef ENOBUFS
	  case ENOBUFS:		/* No buffer space available */
#endif /* ENOBUFS */
#ifdef ENOMEM
	  case ENOMEM:		/* Cannot allocate memory */
#endif /* ENOMEM */
#ifdef ENOSPC
	  case ENOSPC:		/* No space left on device */
#endif /* ENOSPC */
#ifdef EROFS
	  case EROFS:		/* Read-only file system */
#endif /* EROFS */
#ifdef ESTALE
	  case ESTALE:		/* Stale NFS file handle */
#endif /* ESTALE */
#ifdef ETIMEDOUT
	  case ETIMEDOUT:	/* Connection timed out */
#endif /* ETIMEDOUT */
#if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN && EWOULDBLOCK != EDEADLK
	  case EWOULDBLOCK:	/* Operation would block. */
#endif /* defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN && EWOULDBLOCK != EDEADLK */
		ExitVal = EX_TEMPFAIL;
		break;

	  default:
		ExitVal = EX_UNAVAILABLE;
		break;
	}
	return ExitVal;
}

#if defined(ultrix) || defined(_CRAY)
/*
 * Copyright (c) 1987, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

# if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)mktemp.c	8.1 (Berkeley) 6/4/93";
# endif /* defined(LIBC_SCCS) && !defined(lint) */

# include <sys/types.h>
# include <sys/stat.h>
# include <fcntl.h>
# include <errno.h>
# include <stdio.h>
# include <ctype.h>

static int _gettemp();

mkstemp(path)
	char *path;
{
	int fd;

	return (_gettemp(path, &fd) ? fd : -1);
}

# if 0
char *
mktemp(path)
	char *path;
{
	return(_gettemp(path, (int *)NULL) ? path : (char *)NULL);
}
# endif /* 0 */

static
_gettemp(path, doopen)
	char *path;
	register int *doopen;
{
	extern int errno;
	register char *start, *trv;
	struct stat sbuf;
	u_int pid;

	pid = getpid();
	for (trv = path; *trv; ++trv);		/* extra X's get set to 0's */
	while (*--trv == 'X')
	{
		*trv = (pid % 10) + '0';
		pid /= 10;
	}

	/*
	 * check the target directory; if you have six X's and it
	 * doesn't exist this runs for a *very* long time.
	 */
	for (start = trv + 1;; --trv)
	{
		if (trv <= path)
			break;
		if (*trv == '/')
		{
			*trv = '\0';
			if (stat(path, &sbuf) < 0)
				return(0);
			if (!S_ISDIR(sbuf.st_mode))
			{
				errno = ENOTDIR;
				return(0);
			}
			*trv = '/';
			break;
		}
	}

	for (;;)
	{
		if (doopen)
		{
			if ((*doopen = open(path, O_CREAT|O_EXCL|O_RDWR,
					    0600)) >= 0)
				return(1);
			if (errno != EEXIST)
				return(0);
		}
		else if (stat(path, &sbuf) < 0)
			return(errno == ENOENT ? 1 : 0);

		/* tricky little algorithm for backward compatibility */
		for (trv = start;;)
		{
			if (!*trv)
				return(0);
			if (*trv == 'z')
				*trv++ = 'a';
			else
			{
				if (isascii(*trv) && isdigit(*trv))
					*trv = 'a';
				else
					++*trv;
				break;
			}
		}
	}
	/* NOTREACHED */
}
#endif /* defined(ultrix) || defined(_CRAY) */