util.c

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		expand(ProgMailer->m_rootdir, buf, sizeof buf, e);
		if (chroot(buf) < 0)
		{
			syserr("prog_open: cannot chroot(%s)", buf);
			exit(EX_TEMPFAIL);
		}
		if (chdir("/") < 0)
		{
			syserr("prog_open: cannot chdir(/)");
			exit(EX_TEMPFAIL);
		}
	}

	/* run as default user */
	endpwent();
	if (setgid(DefGid) < 0 && geteuid() == 0)
	{
		syserr("prog_open: setgid(%ld) failed", (long) DefGid);
		exit(EX_TEMPFAIL);
	}
	if (setuid(DefUid) < 0 && geteuid() == 0)
	{
		syserr("prog_open: setuid(%ld) failed", (long) DefUid);
		exit(EX_TEMPFAIL);
	}

	/* run in some directory */
	if (ProgMailer != NULL)
		p = ProgMailer->m_execdir;
	else
		p = NULL;
	for (; p != NULL; p = q)
	{
		q = strchr(p, ':');
		if (q != NULL)
			*q = '\0';
		expand(p, buf, sizeof buf, e);
		if (q != NULL)
			*q++ = ':';
		if (buf[0] != '\0' && chdir(buf) >= 0)
			break;
	}
	if (p == NULL)
	{
		/* backup directories */
		if (chdir("/tmp") < 0)
			(void) chdir("/");
	}

	/* arrange for all the files to be closed */
	for (i = 3; i < DtableSize; i++)
	{
		register int j;

		if ((j = fcntl(i, F_GETFD, 0)) != -1)
			(void) fcntl(i, F_SETFD, j | FD_CLOEXEC);
	}

	/* now exec the process */
	(void) execve(argv[0], (ARGV_T) argv, (ARGV_T) UserEnviron);

	/* woops!  failed */
	save_errno = errno;
	syserr("%s: cannot exec", argv[0]);
	if (transienterror(save_errno))
		_exit(EX_OSERR);
	_exit(EX_CONFIG);
	return -1;	/* avoid compiler warning on IRIX */
}
/*
**  GET_COLUMN -- look up a Column in a line buffer
**
**	Parameters:
**		line -- the raw text line to search.
**		col -- the column number to fetch.
**		delim -- the delimiter between columns.  If null,
**			use white space.
**		buf -- the output buffer.
**		buflen -- the length of buf.
**
**	Returns:
**		buf if successful.
**		NULL otherwise.
*/

char *
get_column(line, col, delim, buf, buflen)
	char line[];
	int col;
	int delim;
	char buf[];
	int buflen;
{
	char *p;
	char *begin, *end;
	int i;
	char delimbuf[4];

	if ((char)delim == '\0')
		(void) strlcpy(delimbuf, "\n\t ", sizeof delimbuf);
	else
	{
		delimbuf[0] = (char)delim;
		delimbuf[1] = '\0';
	}

	p = line;
	if (*p == '\0')
		return NULL;			/* line empty */
	if (*p == (char)delim && col == 0)
		return NULL;			/* first column empty */

	begin = line;

	if (col == 0 && (char)delim == '\0')
	{
		while (*begin != '\0' && isascii(*begin) && isspace(*begin))
			begin++;
	}

	for (i = 0; i < col; i++)
	{
		if ((begin = strpbrk(begin, delimbuf)) == NULL)
			return NULL;		/* no such column */
		begin++;
		if ((char)delim == '\0')
		{
			while (*begin != '\0' && isascii(*begin) && isspace(*begin))
				begin++;
		}
	}

	end = strpbrk(begin, delimbuf);
	if (end == NULL)
		i = strlen(begin);
	else
		i = end - begin;
	if (i >= buflen)
		i = buflen - 1;
	(void) strlcpy(buf, begin, i + 1);
	return buf;
}
/*
**  CLEANSTRCPY -- copy string keeping out bogus characters
**
**	Parameters:
**		t -- "to" string.
**		f -- "from" string.
**		l -- length of space available in "to" string.
**
**	Returns:
**		none.
*/

void
cleanstrcpy(t, f, l)
	register char *t;
	register char *f;
	int l;
{
	/* check for newlines and log if necessary */
	(void) denlstring(f, TRUE, TRUE);

	if (l <= 0)
		syserr("!cleanstrcpy: length == 0");

	l--;
	while (l > 0 && *f != '\0')
	{
		if (isascii(*f) &&
		    (isalnum(*f) || strchr("!#$%&'*+-./^_`{|}~", *f) != NULL))
		{
			l--;
			*t++ = *f;
		}
		f++;
	}
	*t = '\0';
}

/*
**  DENLSTRING -- convert newlines in a string to spaces
**
**	Parameters:
**		s -- the input string
**		strict -- if set, don't permit continuation lines.
**		logattacks -- if set, log attempted attacks.
**
**	Returns:
**		A pointer to a version of the string with newlines
**		mapped to spaces.  This should be copied.
*/

char *
denlstring(s, strict, logattacks)
	char *s;
	bool strict;
	bool logattacks;
{
	register char *p;
	int l;
	static char *bp = NULL;
	static int bl = 0;

	p = s;
	while ((p = strchr(p, '\n')) != NULL)
		if (strict || (*++p != ' ' && *p != '\t'))
			break;
	if (p == NULL)
		return s;

	l = strlen(s) + 1;
	if (bl < l)
	{
		/* allocate more space */
		if (bp != NULL)
			free(bp);
		bp = xalloc(l);
		bl = l;
	}
	(void) strlcpy(bp, s, l);
	for (p = bp; (p = strchr(p, '\n')) != NULL; )
		*p++ = ' ';

	if (logattacks)
	{
		sm_syslog(LOG_NOTICE, CurEnv->e_id,
			  "POSSIBLE ATTACK from %.100s: newline in string \"%s\"",
			  RealHostName == NULL ? "[UNKNOWN]" : RealHostName,
			  shortenstring(bp, MAXSHORTSTR));
	}

	return bp;
}
/*
**  PATH_IS_DIR -- check to see if file exists and is a directory.
**
**	There are some additional checks for security violations in
**	here.  This routine is intended to be used for the host status
**	support.
**
**	Parameters:
**		pathname -- pathname to check for directory-ness.
**		createflag -- if set, create directory if needed.
**
**	Returns:
**		TRUE -- if the indicated pathname is a directory
**		FALSE -- otherwise
*/

int
path_is_dir(pathname, createflag)
	char *pathname;
	bool createflag;
{
	struct stat statbuf;

#if HASLSTAT
	if (lstat(pathname, &statbuf) < 0)
#else /* HASLSTAT */
	if (stat(pathname, &statbuf) < 0)
#endif /* HASLSTAT */
	{
		if (errno != ENOENT || !createflag)
			return FALSE;
		if (mkdir(pathname, 0755) < 0)
			return FALSE;
		return TRUE;
	}
	if (!S_ISDIR(statbuf.st_mode))
	{
		errno = ENOTDIR;
		return FALSE;
	}

	/* security: don't allow writable directories */
	if (bitset(S_IWGRP|S_IWOTH, statbuf.st_mode))
	{
		errno = EACCES;
		return FALSE;
	}

	return TRUE;
}
/*
**  PROC_LIST_ADD -- add process id to list of our children
**
**	Parameters:
**		pid -- pid to add to list.
**		task -- task of pid.
**		type -- type of process.
**
**	Returns:
**		none
*/

static struct procs	*ProcListVec = NULL;
static int		ProcListSize = 0;

void
proc_list_add(pid, task, type)
	pid_t pid;
	char *task;
	int type;
{
	int i;

	for (i = 0; i < ProcListSize; i++)
	{
		if (ProcListVec[i].proc_pid == NO_PID)
			break;
	}
	if (i >= ProcListSize)
	{
		/* probe the existing vector to avoid growing infinitely */
		proc_list_probe();

		/* now scan again */
		for (i = 0; i < ProcListSize; i++)
		{
			if (ProcListVec[i].proc_pid == NO_PID)
				break;
		}
	}
	if (i >= ProcListSize)
	{
		/* grow process list */
		struct procs *npv;

		npv = (struct procs *) xalloc((sizeof *npv) *
					      (ProcListSize + PROC_LIST_SEG));
		if (ProcListSize > 0)
		{
			memmove(npv, ProcListVec,
				ProcListSize * sizeof (struct procs));
			free(ProcListVec);
		}
		for (i = ProcListSize; i < ProcListSize + PROC_LIST_SEG; i++)
		{
			npv[i].proc_pid = NO_PID;
			npv[i].proc_task = NULL;
			npv[i].proc_type = PROC_NONE;
		}
		i = ProcListSize;
		ProcListSize += PROC_LIST_SEG;
		ProcListVec = npv;
	}
	ProcListVec[i].proc_pid = pid;
	if (ProcListVec[i].proc_task != NULL)
		free(ProcListVec[i].proc_task);
	ProcListVec[i].proc_task = newstr(task);
	ProcListVec[i].proc_type = type;

	/* if process adding itself, it's not a child */
	if (pid != getpid())
		CurChildren++;
}
/*
**  PROC_LIST_SET -- set pid task in process list
**
**	Parameters:
**		pid -- pid to set
**		task -- task of pid
**
**	Returns:
**		none.
*/

void
proc_list_set(pid, task)
	pid_t pid;
	char *task;
{
	int i;

	for (i = 0; i < ProcListSize; i++)
	{
		if (ProcListVec[i].proc_pid == pid)
		{
			if (ProcListVec[i].proc_task != NULL)
				free(ProcListVec[i].proc_task);
			ProcListVec[i].proc_task = newstr(task);
			break;
		}
	}
}
/*
**  PROC_LIST_DROP -- drop pid from process list
**
**	Parameters:
**		pid -- pid to drop
**
**	Returns:
**		type of process
*/

int
proc_list_drop(pid)
	pid_t pid;
{
	int i;
	int type = PROC_NONE;

	for (i = 0; i < ProcListSize; i++)
	{
		if (ProcListVec[i].proc_pid == pid)
		{
			ProcListVec[i].proc_pid = NO_PID;
			type = ProcListVec[i].proc_type;
			break;
		}
	}
	if (CurChildren > 0)
		CurChildren--;


	return type;
}
/*
**  PROC_LIST_CLEAR -- clear the process list
**
**	Parameters:
**		none.
**
**	Returns:
**		none.
*/

void
proc_list_clear()
{
	int i;

	/* start from 1 since 0 is the daemon itself */
	for (i = 1; i < ProcListSize; i++)
	{
		ProcListVec[i].proc_pid = NO_PID;
	}
	CurChildren = 0;
}
/*
**  PROC_LIST_PROBE -- probe processes in the list to see if they still exist
**
**	Parameters:
**		none
**
**	Returns:
**		none
*/

void
proc_list_probe()
{
	int i;

	/* start from 1 since 0 is the daemon itself */
	for (i = 1; i < ProcListSize; i++)
	{
		if (ProcListVec[i].proc_pid == NO_PID)
			continue;
		if (kill(ProcListVec[i].proc_pid, 0) < 0)
		{
			if (LogLevel > 3)
				sm_syslog(LOG_DEBUG, CurEnv->e_id,
					  "proc_list_probe: lost pid %d",
					  (int) ProcListVec[i].proc_pid);
			ProcListVec[i].proc_pid = NO_PID;
			CurChildren--;
		}
	}
	if (CurChildren < 0)
		CurChildren = 0;
}
/*
**  PROC_LIST_DISPLAY -- display the process list
**
**	Parameters:
**		out -- output file pointer
**
**	Returns:
**		none.
*/

void
proc_list_display(out)
	FILE *out;
{
	int i;

	for (i = 0; i < ProcListSize; i++)
	{
		if (ProcListVec[i].proc_pid == NO_PID)
			continue;

		fprintf(out, "%d %s%s\n", (int) ProcListVec[i].proc_pid,
			ProcListVec[i].proc_task != NULL ?
			ProcListVec[i].proc_task : "(unknown)",
			(OpMode == MD_SMTP ||
			 OpMode == MD_DAEMON ||
			 OpMode == MD_ARPAFTP) ? "\r" : "");
	}
}
/*
**  SM_STRCASECMP -- 8-bit clean version of strcasecmp
**
**	Thank you, vendors, for making this all necessary.
*/

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

/*
 * This array is designed for mapping upper and lower case letter
 * together for a case independent comparison.  The mappings are
 * based upon ascii character sequences.
 */
static const u_char charmap[] = {
	0000, 0001, 0002, 0003, 0004, 0005, 0006, 0007,
	0010, 0011, 0012, 0013, 0014, 0015, 0016, 0017,
	0020, 0021, 0022, 0023, 0024, 0025, 0026, 0027,
	0030, 0031, 0032, 0033, 0034, 0035, 0036, 0037,
	0040, 0041, 0042, 0043, 0044, 0045, 0046, 0047,
	0050, 0051, 0052, 0053, 0054, 0055, 0056, 0057,
	0060, 0061, 0062, 0063, 0064, 0065, 0066, 0067,
	0070, 0071, 0072, 0073, 0074, 0075, 0076, 0077,
	0100, 0141, 0142, 0143, 0144, 0145, 0146, 0147,
	0150, 0151, 0152, 0153, 0154, 0155, 0156, 0157,
	0160, 0161, 0162, 0163, 0164, 0165, 0166, 0167,
	0170, 0171, 0172, 0133, 0134, 0135, 0136, 0137,
	0140, 0141, 0142, 0143, 0144, 0145, 0146, 0147,
	0150, 0151, 0152, 0153, 0154, 0155, 0156, 0157,
	0160, 0161, 0162, 0163, 0164, 0165, 0166, 0167,
	0170, 0171, 0172, 0173, 0174, 0175, 0176, 0177,
	0200, 0201, 0202, 0203, 0204, 0205, 0206, 0207,
	0210, 0211, 0212, 0213, 0214, 0215, 0216, 0217,
	0220, 0221, 0222, 0223, 0224, 0225, 0226, 0227,
	0230, 0231, 0232, 0233, 0234, 0235, 0236, 0237,
	0240, 0241, 0242, 0243, 0244, 0245, 0246, 0247,
	0250, 0251, 0252, 0253, 0254, 0255, 0256, 0257,
	0260, 0261, 0262, 0263, 0264, 0265, 0266, 0267,
	0270, 0271, 0272, 0273, 0274, 0275, 0276, 0277,
	0300, 0301, 0302, 0303, 0304, 0305, 0306, 0307,
	0310, 0311, 0312, 0313, 0314, 0315, 0316, 0317,
	0320, 0321, 0322, 0323, 0324, 0325, 0326, 0327,
	0330, 0331, 0332, 0333, 0334, 0335, 0336, 0337,
	0340, 0341, 0342, 0343, 0344, 0345, 0346, 0347,
	0350, 0351, 0352, 0353, 0354, 0355, 0356, 0357,
	0360, 0361, 0362, 0363, 0364, 0365, 0366, 0367,
	0370, 0371, 0372, 0373, 0374, 0375, 0376, 0377,
};

int
sm_strcasecmp(s1, s2)
	const char *s1, *s2;
{
	register const u_char *cm = charmap,
			*us1 = (const u_char *)s1,
			*us2 = (const u_char *)s2;

	while (cm[*us1] == cm[*us2++])
		if (*us1++ == '\0')
			return 0;
	return (cm[*us1] - cm[*--us2]);
}

int
sm_strncasecmp(s1, s2, n)
	const char *s1, *s2;
	register size_t n;
{
	if (n != 0) {
		register const u_char *cm = charmap,
				*us1 = (const u_char *)s1,
				*us2 = (const u_char *)s2;

		do {
			if (cm[*us1] != cm[*us2++])
				return (cm[*us1] - cm[*--us2]);
			if (*us1++ == '\0')
				break;
		} while (--n != 0);
	}
	return 0;
}