parseaddr.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[] = "@(#)parseaddr.c	8.31 (Berkeley) 4/15/94";
#endif /* not lint */

# include "sendmail.h"

/*
**  PARSEADDR -- Parse an address
**
**	Parses an address and breaks it up into three parts: a
**	net to transmit the message on, the host to transmit it
**	to, and a user on that host.  These are loaded into an
**	ADDRESS header with the values squirreled away if necessary.
**	The "user" part may not be a real user; the process may
**	just reoccur on that machine.  For example, on a machine
**	with an arpanet connection, the address
**		csvax.bill@berkeley
**	will break up to a "user" of 'csvax.bill' and a host
**	of 'berkeley' -- to be transmitted over the arpanet.
**
**	Parameters:
**		addr -- the address to parse.
**		a -- a pointer to the address descriptor buffer.
**			If NULL, a header will be created.
**		flags -- describe detail for parsing.  See RF_ definitions
**			in sendmail.h.
**		delim -- the character to terminate the address, passed
**			to prescan.
**		delimptr -- if non-NULL, set to the location of the
**			delim character that was found.
**		e -- the envelope that will contain this address.
**
**	Returns:
**		A pointer to the address descriptor header (`a' if
**			`a' is non-NULL).
**		NULL on error.
**
**	Side Effects:
**		none
*/

/* following delimiters are inherent to the internal algorithms */
# define DELIMCHARS	"()<>,;\r\n"	/* default word delimiters */

ADDRESS *
parseaddr(addr, a, flags, delim, delimptr, e)
	char *addr;
	register ADDRESS *a;
	int flags;
	int delim;
	char **delimptr;
	register ENVELOPE *e;
{
	register char **pvp;
	auto char *delimptrbuf;
	bool queueup;
	char pvpbuf[PSBUFSIZE];
	extern ADDRESS *buildaddr();
	extern bool invalidaddr();

	/*
	**  Initialize and prescan address.
	*/

	e->e_to = addr;
	if (tTd(20, 1))
		printf("\n--parseaddr(%s)\n", addr);

	if (delimptr == NULL)
		delimptr = &delimptrbuf;

	pvp = prescan(addr, delim, pvpbuf, sizeof pvpbuf, delimptr);
	if (pvp == NULL)
	{
		if (tTd(20, 1))
			printf("parseaddr-->NULL\n");
		return (NULL);
	}

	if (invalidaddr(addr, delim == '\0' ? NULL : *delimptr))
	{
		if (tTd(20, 1))
			printf("parseaddr-->bad address\n");
		return NULL;
	}

	/*
	**  Save addr if we are going to have to.
	**
	**	We have to do this early because there is a chance that
	**	the map lookups in the rewriting rules could clobber
	**	static memory somewhere.
	*/

	if (bitset(RF_COPYPADDR, flags) && addr != NULL)
	{
		char savec = **delimptr;

		if (savec != '\0')
			**delimptr = '\0';
		e->e_to = addr = newstr(addr);
		if (savec != '\0')
			**delimptr = savec;
	}

	/*
	**  Apply rewriting rules.
	**	Ruleset 0 does basic parsing.  It must resolve.
	*/

	queueup = FALSE;
	if (rewrite(pvp, 3, 0, e) == EX_TEMPFAIL)
		queueup = TRUE;
	if (rewrite(pvp, 0, 0, e) == EX_TEMPFAIL)
		queueup = TRUE;


	/*
	**  Build canonical address from pvp.
	*/

	a = buildaddr(pvp, a, flags, e);

	/*
	**  Make local copies of the host & user and then
	**  transport them out.
	*/

	allocaddr(a, flags, addr);
	if (bitset(QBADADDR, a->q_flags))
		return a;

	/*
	**  If there was a parsing failure, mark it for queueing.
	*/

	if (queueup)
	{
		char *msg = "Transient parse error -- message queued for future delivery";

		if (tTd(20, 1))
			printf("parseaddr: queuing message\n");
		message(msg);
		if (e->e_message == NULL)
			e->e_message = newstr(msg);
		a->q_flags |= QQUEUEUP;
	}

	/*
	**  Compute return value.
	*/

	if (tTd(20, 1))
	{
		printf("parseaddr-->");
		printaddr(a, FALSE);
	}

	return (a);
}
/*
**  INVALIDADDR -- check for address containing meta-characters
**
**	Parameters:
**		addr -- the address to check.
**
**	Returns:
**		TRUE -- if the address has any "wierd" characters
**		FALSE -- otherwise.
*/

bool
invalidaddr(addr, delimptr)
	register char *addr;
	char *delimptr;
{
	char savedelim;

	if (delimptr != NULL)
	{
		savedelim = *delimptr;
		if (savedelim != '\0')
			*delimptr = '\0';
	}
#if 0
	/* for testing.... */
	if (strcmp(addr, "INvalidADDR") == 0)
	{
		usrerr("553 INvalid ADDRess");
		goto addrfailure;
	}
#endif
	for (; *addr != '\0'; addr++)
	{
		if ((*addr & 0340) == 0200)
			break;
	}
	if (*addr == '\0')
	{
		if (savedelim != '\0' && delimptr != NULL)
			*delimptr = savedelim;
		return FALSE;
	}
	setstat(EX_USAGE);
	usrerr("553 Address contained invalid control characters");
  addrfailure:
	if (savedelim != '\0' && delimptr != NULL)
		*delimptr = savedelim;
	return TRUE;
}
/*
**  ALLOCADDR -- do local allocations of address on demand.
**
**	Also lowercases the host name if requested.
**
**	Parameters:
**		a -- the address to reallocate.
**		flags -- the copy flag (see RF_ definitions in sendmail.h
**			for a description).
**		paddr -- the printname of the address.
**
**	Returns:
**		none.
**
**	Side Effects:
**		Copies portions of a into local buffers as requested.
*/

allocaddr(a, flags, paddr)
	register ADDRESS *a;
	int flags;
	char *paddr;
{
	if (tTd(24, 4))
		printf("allocaddr(flags=%o, paddr=%s)\n", flags, paddr);

	a->q_paddr = paddr;

	if (a->q_user == NULL)
		a->q_user = "";
	if (a->q_host == NULL)
		a->q_host = "";

	if (bitset(RF_COPYPARSE, flags))
	{
		a->q_host = newstr(a->q_host);
		if (a->q_user != a->q_paddr)
			a->q_user = newstr(a->q_user);
	}

	if (a->q_paddr == NULL)
		a->q_paddr = a->q_user;
}
/*
**  PRESCAN -- Prescan name and make it canonical
**
**	Scans a name and turns it into a set of tokens.  This process
**	deletes blanks and comments (in parentheses).
**
**	This routine knows about quoted strings and angle brackets.
**
**	There are certain subtleties to this routine.  The one that
**	comes to mind now is that backslashes on the ends of names
**	are silently stripped off; this is intentional.  The problem
**	is that some versions of sndmsg (like at LBL) set the kill
**	character to something other than @ when reading addresses;
**	so people type "csvax.eric\@berkeley" -- which screws up the
**	berknet mailer.
**
**	Parameters:
**		addr -- the name to chomp.
**		delim -- the delimiter for the address, normally
**			'\0' or ','; \0 is accepted in any case.
**			If '\t' then we are reading the .cf file.
**		pvpbuf -- place to put the saved text -- note that
**			the pointers are static.
**		pvpbsize -- size of pvpbuf.
**		delimptr -- if non-NULL, set to the location of the
**			terminating delimiter.
**
**	Returns:
**		A pointer to a vector of tokens.
**		NULL on error.
*/

/* states and character types */
# define OPR		0	/* operator */
# define ATM		1	/* atom */
# define QST		2	/* in quoted string */
# define SPC		3	/* chewing up spaces */
# define ONE		4	/* pick up one character */

# define NSTATES	5	/* number of states */
# define TYPE		017	/* mask to select state type */

/* meta bits for table */
# define M		020	/* meta character; don't pass through */
# define B		040	/* cause a break */
# define MB		M|B	/* meta-break */

static short StateTab[NSTATES][NSTATES] =
{
   /*	oldst	chtype>	OPR	ATM	QST	SPC	ONE	*/
	/*OPR*/		OPR|B,	ATM|B,	QST|B,	SPC|MB,	ONE|B,
	/*ATM*/		OPR|B,	ATM,	QST|B,	SPC|MB,	ONE|B,
	/*QST*/		QST,	QST,	OPR,	QST,	QST,
	/*SPC*/		OPR,	ATM,	QST,	SPC|M,	ONE,
	/*ONE*/		OPR,	OPR,	OPR,	OPR,	OPR,
};

/* token type table -- it gets modified with $o characters */
static TokTypeTab[256] =
{
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,SPC,SPC,SPC,SPC,SPC,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	SPC,ATM,QST,ATM,ATM,ATM,ATM,ATM,ATM,SPC,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	OPR,OPR,ONE,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,
	OPR,OPR,OPR,ONE,ONE,ONE,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,OPR,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
	ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,ATM,
};

#define toktype(c)	((int) TokTypeTab[(c) & 0xff])


# define NOCHAR		-1	/* signal nothing in lookahead token */

char **
prescan(addr, delim, pvpbuf, pvpbsize, delimptr)
	char *addr;
	char delim;
	char pvpbuf[];
	char **delimptr;
{
	register char *p;
	register char *q;
	register int c;
	char **avp;
	bool bslashmode;
	int cmntcnt;
	int anglecnt;
	char *tok;
	int state;
	int newstate;
	char *saveto = CurEnv->e_to;
	static char *av[MAXATOM+1];
	static char firsttime = TRUE;
	extern int errno;

	if (firsttime)
	{
		/* initialize the token type table */
		char obuf[50];

		firsttime = FALSE;
		expand("\201o", obuf, &obuf[sizeof obuf - sizeof DELIMCHARS], CurEnv);
		strcat(obuf, DELIMCHARS);
		for (p = obuf; *p != '\0'; p++)
		{
			if (TokTypeTab[*p & 0xff] == ATM)
				TokTypeTab[*p & 0xff] = OPR;
		}
	}

	/* make sure error messages don't have garbage on them */
	errno = 0;

	q = pvpbuf;
	bslashmode = FALSE;
	cmntcnt = 0;
	anglecnt = 0;
	avp = av;
	state = ATM;
	c = NOCHAR;
	p = addr;
	CurEnv->e_to = p;
	if (tTd(22, 11))
	{
		printf("prescan: ");
		xputs(p);
		(void) putchar('\n');
	}

	do
	{
		/* read a token */
		tok = q;
		for (;;)
		{
			/* store away any old lookahead character */
			if (c != NOCHAR && !bslashmode)
			{
				/* see if there is room */
				if (q >= &pvpbuf[pvpbsize - 5])
				{
					usrerr("553 Address too long");
	returnnull:
					if (delimptr != NULL)
						*delimptr = p;
					CurEnv->e_to = saveto;
					return (NULL);
				}

				/* squirrel it away */
				*q++ = c;
			}

			/* read a new input character */
			c = *p++;
			if (c == '\0')
			{
				/* diagnose and patch up bad syntax */
				if (state == QST)
				{
					usrerr("653 Unbalanced '\"'");
					c = '"';
				}
				else if (cmntcnt > 0)
				{
					usrerr("653 Unbalanced '('");
					c = ')';
				}
				else if (anglecnt > 0)
				{
					c = '>';
					usrerr("653 Unbalanced '<'");
				}
				else
					break;

				p--;
			}
			else if (c == delim && anglecnt <= 0 &&
					cmntcnt <= 0 && state != QST)
				break;

			if (tTd(22, 101))
				printf("c=%c, s=%d; ", c, state);

			/* chew up special characters */
			*q = '\0';
			if (bslashmode)
			{
				bslashmode = FALSE;

				/* kludge \! for naive users */
				if (cmntcnt > 0)
				{
					c = NOCHAR;
					continue;
				}
				else if (c != '!' || state == QST)
				{
					*q++ = '\\';
					continue;
				}
			}

			if (c == '\\')
			{
				bslashmode = TRUE;
			}
			else if (state == QST)
			{
				/* do nothing, just avoid next clauses */
			}
			else if (c == '(')
			{
				cmntcnt++;
				c = NOCHAR;
			}
			else if (c == ')')
			{
				if (cmntcnt <= 0)
				{
					usrerr("653 Unbalanced ')'");
					c = NOCHAR;
				}
				else
					cmntcnt--;
			}
			else if (cmntcnt > 0)
				c = NOCHAR;
			else if (c == '<')
				anglecnt++;
			else if (c == '>')
			{
				if (anglecnt <= 0)
				{
					usrerr("653 Unbalanced '>'");
					c = NOCHAR;
				}
				else
					anglecnt--;
			}
			else if (delim == ' ' && isascii(c) && isspace(c))
				c = ' ';

			if (c == NOCHAR)
				continue;

			/* see if this is end of input */
			if (c == delim && anglecnt <= 0 && state != QST)
				break;

			newstate = StateTab[state][toktype(c)];
			if (tTd(22, 101))
				printf("ns=%02o\n", newstate);
			state = newstate & TYPE;
			if (bitset(M, newstate))
				c = NOCHAR;
			if (bitset(B, newstate))
				break;
		}

		/* new token */
		if (tok != q)
		{
			*q++ = '\0';
			if (tTd(22, 36))
			{
				printf("tok=");
				xputs(tok);
				(void) putchar('\n');
			}
			if (avp >= &av[MAXATOM])
			{
				syserr("553 prescan: too many tokens");
				goto returnnull;
			}
			if (q - tok > MAXNAME)
			{
				syserr("553 prescan: token too long");
				goto returnnull;
			}
			*avp++ = tok;
		}
	} while (c != '\0' && (c != delim || anglecnt > 0));
	*avp = NULL;
	p--;
	if (delimptr != NULL)
		*delimptr = p;
	if (tTd(22, 12))
	{
		printf("prescan==>");
		printav(av);
	}
	CurEnv->e_to = saveto;
	if (av[0] == NULL)
	{
		if (tTd(22, 1))
			printf("prescan: null leading token\n");
		return (NULL);
	}
	return (av);
}
/*
**  REWRITE -- apply rewrite rules to token vector.
**
**	This routine is an ordered production system.  Each rewrite
**	rule has a LHS (called the pattern) and a RHS (called the
**	rewrite); 'rwr' points the the current rewrite rule.
**
**	For each rewrite rule, 'avp' points the address vector we
**	are trying to match against, and 'pvp' points to the pattern.
**	If pvp points to a special match value (MATCHZANY, MATCHANY,
**	MATCHONE, MATCHCLASS, MATCHNCLASS) then the address in avp
**	matched is saved away in the match vector (pointed to by 'mvp').
**
**	When a match between avp & pvp does not match, we try to
**	back out.  If we back up over MATCHONE, MATCHCLASS, or MATCHNCLASS
**	we must also back out the match in mvp.  If we reach a
**	MATCHANY or MATCHZANY we just extend the match and start
**	over again.
**
**	When we finally match, we rewrite the address vector
**	and try over again.
**
**	Parameters:
**		pvp -- pointer to token vector.
**		ruleset -- the ruleset to use for rewriting.
**		reclevel -- recursion level (to catch loops).
**		e -- the current envelope.
**
**	Returns:
**		A status code.  If EX_TEMPFAIL, higher level code should
**			attempt recovery.
**
**	Side Effects:
**		pvp is modified.
*/

struct match
{
	char	**first;	/* first token matched */
	char	**last;		/* last token matched */
	char	**pattern;	/* pointer to pattern */
};

# define MAXMATCH	9	/* max params per rewrite */

# ifndef MAXRULERECURSION
#  define MAXRULERECURSION	50	/* max recursion depth */
# endif


int
rewrite(pvp, ruleset, reclevel, e)
	char **pvp;
	int ruleset;
	int reclevel;
	register ENVELOPE *e;