readcf.c

早期freebsd实现

/*
 * Copyright (c) 1983 Eric P. Allman
 * Copyright (c) 1988, 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.
 */

#ifndef lint
static char sccsid[] = "@(#)readcf.c	8.23 (Berkeley) 3/18/94";
#endif /* not lint */

# include "sendmail.h"
# include <pwd.h>
# include <grp.h>
#if NAMED_BIND
# include <arpa/nameser.h>
# include <resolv.h>
#endif

/*
**  READCF -- read control file.
**
**	This routine reads the control file and builds the internal
**	form.
**
**	The file is formatted as a sequence of lines, each taken
**	atomically.  The first character of each line describes how
**	the line is to be interpreted.  The lines are:
**		Dxval		Define macro x to have value val.
**		Cxword		Put word into class x.
**		Fxfile [fmt]	Read file for lines to put into
**				class x.  Use scanf string 'fmt'
**				or "%s" if not present.  Fmt should
**				only produce one string-valued result.
**		Hname: value	Define header with field-name 'name'
**				and value as specified; this will be
**				macro expanded immediately before
**				use.
**		Sn		Use rewriting set n.
**		Rlhs rhs	Rewrite addresses that match lhs to
**				be rhs.
**		Mn arg=val...	Define mailer.  n is the internal name.
**				Args specify mailer parameters.
**		Oxvalue		Set option x to value.
**		Pname=value	Set precedence name to value.
**		Vversioncode[/vendorcode]
**				Version level/vendor name of
**				configuration syntax.
**		Kmapname mapclass arguments....
**				Define keyed lookup of a given class.
**				Arguments are class dependent.
**
**	Parameters:
**		cfname -- control file name.
**		safe -- TRUE if this is the system config file;
**			FALSE otherwise.
**		e -- the main envelope.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Builds several internal tables.
*/

readcf(cfname, safe, e)
	char *cfname;
	bool safe;
	register ENVELOPE *e;
{
	FILE *cf;
	int ruleset = 0;
	char *q;
	struct rewrite *rwp = NULL;
	char *bp;
	auto char *ep;
	int nfuzzy;
	char *file;
	bool optional;
	char buf[MAXLINE];
	register char *p;
	extern char **copyplist();
	struct stat statb;
	char exbuf[MAXLINE];
	char pvpbuf[MAXLINE + MAXATOM];
	extern char *munchstring();
	extern void makemapentry();

	FileName = cfname;
	LineNumber = 0;

	cf = fopen(cfname, "r");
	if (cf == NULL)
	{
		syserr("cannot open");
		exit(EX_OSFILE);
	}

	if (fstat(fileno(cf), &statb) < 0)
	{
		syserr("cannot fstat");
		exit(EX_OSFILE);
	}

	if (!S_ISREG(statb.st_mode))
	{
		syserr("not a plain file");
		exit(EX_OSFILE);
	}

	if (OpMode != MD_TEST && bitset(S_IWGRP|S_IWOTH, statb.st_mode))
	{
		if (OpMode == MD_DAEMON || OpMode == MD_FREEZE)
			fprintf(stderr, "%s: WARNING: dangerous write permissions\n",
				FileName);
#ifdef LOG
		if (LogLevel > 0)
			syslog(LOG_CRIT, "%s: WARNING: dangerous write permissions",
				FileName);
#endif
	}

#ifdef XLA
	xla_zero();
#endif

	while ((bp = fgetfolded(buf, sizeof buf, cf)) != NULL)
	{
		if (bp[0] == '#')
		{
			if (bp != buf)
				free(bp);
			continue;
		}

		/* map $ into \201 for macro expansion */
		for (p = bp; *p != '\0'; p++)
		{
			if (*p == '#' && p > bp && ConfigLevel >= 3)
			{
				/* this is an on-line comment */
				register char *e;

				switch (*--p & 0377)
				{
				  case MACROEXPAND:
					/* it's from $# -- let it go through */
					p++;
					break;

				  case '\\':
					/* it's backslash escaped */
					(void) strcpy(p, p + 1);
					break;

				  default:
					/* delete preceeding white space */
					while (isascii(*p) && isspace(*p) && p > bp)
						p--;
					if ((e = strchr(++p, '\n')) != NULL)
						(void) strcpy(p, e);
					else
						p[0] = p[1] = '\0';
					break;
				}
				continue;
			}

			if (*p != '$')
				continue;

			if (p[1] == '$')
			{
				/* actual dollar sign.... */
				(void) strcpy(p, p + 1);
				continue;
			}

			/* convert to macro expansion character */
			*p = MACROEXPAND;
		}

		/* interpret this line */
		errno = 0;
		switch (bp[0])
		{
		  case '\0':
		  case '#':		/* comment */
			break;

		  case 'R':		/* rewriting rule */
			for (p = &bp[1]; *p != '\0' && *p != '\t'; p++)
				continue;

			if (*p == '\0')
			{
				syserr("invalid rewrite line \"%s\" (tab expected)", bp);
				break;
			}

			/* allocate space for the rule header */
			if (rwp == NULL)
			{
				RewriteRules[ruleset] = rwp =
					(struct rewrite *) xalloc(sizeof *rwp);
			}
			else
			{
				rwp->r_next = (struct rewrite *) xalloc(sizeof *rwp);
				rwp = rwp->r_next;
			}
			rwp->r_next = NULL;

			/* expand and save the LHS */
			*p = '\0';
			expand(&bp[1], exbuf, &exbuf[sizeof exbuf], e);
			rwp->r_lhs = prescan(exbuf, '\t', pvpbuf,
					     sizeof pvpbuf, NULL);
			nfuzzy = 0;
			if (rwp->r_lhs != NULL)
			{
				register char **ap;

				rwp->r_lhs = copyplist(rwp->r_lhs, TRUE);

				/* count the number of fuzzy matches in LHS */
				for (ap = rwp->r_lhs; *ap != NULL; ap++)
				{
					char *botch;

					botch = NULL;
					switch (**ap & 0377)
					{
					  case MATCHZANY:
					  case MATCHANY:
					  case MATCHONE:
					  case MATCHCLASS:
					  case MATCHNCLASS:
						nfuzzy++;
						break;

					  case MATCHREPL:
						botch = "$0-$9";
						break;

					  case CANONNET:
						botch = "$#";
						break;

					  case CANONUSER:
						botch = "$:";
						break;

					  case CALLSUBR:
						botch = "$>";
						break;

					  case CONDIF:
						botch = "$?";
						break;

					  case CONDELSE:
						botch = "$|";
						break;

					  case CONDFI:
						botch = "$.";
						break;

					  case HOSTBEGIN:
						botch = "$[";
						break;

					  case HOSTEND:
						botch = "$]";
						break;

					  case LOOKUPBEGIN:
						botch = "$(";
						break;

					  case LOOKUPEND:
						botch = "$)";
						break;
					}
					if (botch != NULL)
						syserr("Inappropriate use of %s on LHS",
							botch);
				}
			}
			else
				syserr("R line: null LHS");

			/* expand and save the RHS */
			while (*++p == '\t')
				continue;
			q = p;
			while (*p != '\0' && *p != '\t')
				p++;
			*p = '\0';
			expand(q, exbuf, &exbuf[sizeof exbuf], e);
			rwp->r_rhs = prescan(exbuf, '\t', pvpbuf,
					     sizeof pvpbuf, NULL);
			if (rwp->r_rhs != NULL)
			{
				register char **ap;

				rwp->r_rhs = copyplist(rwp->r_rhs, TRUE);

				/* check no out-of-bounds replacements */
				nfuzzy += '0';
				for (ap = rwp->r_rhs; *ap != NULL; ap++)
				{
					char *botch;

					botch = NULL;
					switch (**ap & 0377)
					{
					  case MATCHREPL:
						if ((*ap)[1] <= '0' || (*ap)[1] > nfuzzy)
						{
							syserr("replacement $%c out of bounds",
								(*ap)[1]);
						}
						break;

					  case MATCHZANY:
						botch = "$*";
						break;

					  case MATCHANY:
						botch = "$+";
						break;

					  case MATCHONE:
						botch = "$-";
						break;

					  case MATCHCLASS:
						botch = "$=";
						break;

					  case MATCHNCLASS:
						botch = "$~";
						break;
					}
					if (botch != NULL)
						syserr("Inappropriate use of %s on RHS",
							botch);
				}
			}
			else
				syserr("R line: null RHS");
			break;

		  case 'S':		/* select rewriting set */
			for (p = &bp[1]; isascii(*p) && isspace(*p); p++)
				continue;
			if (!isascii(*p) || !isdigit(*p))
			{
				syserr("invalid argument to S line: \"%.20s\"", 
					&bp[1]);
				break;
			}
			ruleset = atoi(p);
			if (ruleset >= MAXRWSETS || ruleset < 0)
			{
				syserr("bad ruleset %d (%d max)", ruleset, MAXRWSETS);
				ruleset = 0;
			}
			rwp = NULL;
			break;

		  case 'D':		/* macro definition */
			p = munchstring(&bp[2], NULL);
			define(bp[1], newstr(p), e);
			break;

		  case 'H':		/* required header line */
			(void) chompheader(&bp[1], TRUE, e);
			break;

		  case 'C':		/* word class */
			/* scan the list of words and set class for all */
			expand(&bp[2], exbuf, &exbuf[sizeof exbuf], e);
			for (p = exbuf; *p != '\0'; )
			{
				register char *wd;
				char delim;

				while (*p != '\0' && isascii(*p) && isspace(*p))
					p++;
				wd = p;
				while (*p != '\0' && !(isascii(*p) && isspace(*p)))
					p++;
				delim = *p;
				*p = '\0';
				if (wd[0] != '\0')
					setclass(bp[1], wd);
				*p = delim;
			}
			break;

		  case 'F':		/* word class from file */
			for (p = &bp[2]; isascii(*p) && isspace(*p); )
				p++;
			if (p[0] == '-' && p[1] == 'o')
			{
				optional = TRUE;
				while (*p != '\0' && !(isascii(*p) && isspace(*p)))
					p++;
				while (isascii(*p) && isspace(*p))
					*p++;
			}
			else
				optional = FALSE;
			file = p;
			while (*p != '\0' && !(isascii(*p) && isspace(*p)))
				p++;
			if (*p == '\0')
				p = "%s";
			else
			{
				*p = '\0';
				while (isascii(*++p) && isspace(*p))
					continue;
			}
			fileclass(bp[1], file, p, safe, optional);
			break;

#ifdef XLA
		  case 'L':		/* extended load average description */
			xla_init(&bp[1]);
			break;
#endif

		  case 'M':		/* define mailer */
			makemailer(&bp[1]);
			break;

		  case 'O':		/* set option */
			setoption(bp[1], &bp[2], safe, FALSE, e);
			break;

		  case 'P':		/* set precedence */
			if (NumPriorities >= MAXPRIORITIES)
			{
				toomany('P', MAXPRIORITIES);
				break;
			}
			for (p = &bp[1]; *p != '\0' && *p != '=' && *p != '\t'; p++)
				continue;
			if (*p == '\0')
				goto badline;
			*p = '\0';
			Priorities[NumPriorities].pri_name = newstr(&bp[1]);
			Priorities[NumPriorities].pri_val = atoi(++p);
			NumPriorities++;
			break;

		  case 'T':		/* trusted user(s) */
			/* this option is obsolete, but will be ignored */
			break;

		  case 'V':		/* configuration syntax version */
			for (p = &bp[1]; isascii(*p) && isspace(*p); p++)
				continue;
			if (!isascii(*p) || !isdigit(*p))
			{
				syserr("invalid argument to V line: \"%.20s\"", 
					&bp[1]);
				break;
			}
			ConfigLevel = strtol(p, &ep, 10);
			if (ConfigLevel >= 5)
			{
				/* level 5 configs have short name in $w */
				p = macvalue('w', e);
				if (p != NULL && (p = strchr(p, '.')) != NULL)
					*p = '\0';
			}
			if (*ep++ == '/')
			{
				/* extract vendor code */
				for (p = ep; isascii(*p) && isalpha(*p); )
					p++;
				*p = '\0';

				if (!setvendor(ep))
					syserr("invalid V line vendor code: \"%s\"",
						ep);
			}
			break;

		  case 'K':
			makemapentry(&bp[1]);
			break;

		  default:
		  badline:
			syserr("unknown control line \"%s\"", bp);
		}
		if (bp != buf)
			free(bp);
	}
	if (ferror(cf))
	{
		syserr("I/O read error", cfname);
		exit(EX_OSFILE);
	}
	fclose(cf);
	FileName = NULL;

	if (stab("host", ST_MAP, ST_FIND) == NULL)
	{
		/* user didn't initialize: set up host map */
		strcpy(buf, "host host");
#if NAMED_BIND
		if (ConfigLevel >= 2)
			strcat(buf, " -a.");
#endif
		makemapentry(buf);
	}
}
/*
**  TOOMANY -- signal too many of some option
**
**	Parameters:
**		id -- the id of the error line
**		maxcnt -- the maximum possible values
**
**	Returns:
**		none.
**