1 /*
2  * Copyright (c) 1983 Eric P. Allman
3  * Copyright (c) 1988 Regents of the University of California.
4  * All rights reserved.
5  *
6  * %sccs.include.redist.c%
7  */
8 
9 #ifndef lint
10 static char sccsid[] = "@(#)parseaddr.c	6.20 (Berkeley) 02/24/93";
11 #endif /* not lint */
12 
13 # include "sendmail.h"
14 
15 /*
16 **  PARSEADDR -- Parse an address
17 **
18 **	Parses an address and breaks it up into three parts: a
19 **	net to transmit the message on, the host to transmit it
20 **	to, and a user on that host.  These are loaded into an
21 **	ADDRESS header with the values squirreled away if necessary.
22 **	The "user" part may not be a real user; the process may
23 **	just reoccur on that machine.  For example, on a machine
24 **	with an arpanet connection, the address
25 **		csvax.bill@berkeley
26 **	will break up to a "user" of 'csvax.bill' and a host
27 **	of 'berkeley' -- to be transmitted over the arpanet.
28 **
29 **	Parameters:
30 **		addr -- the address to parse.
31 **		a -- a pointer to the address descriptor buffer.
32 **			If NULL, a header will be created.
33 **		copyf -- determines what shall be copied:
34 **			-1 -- don't copy anything.  The printname
35 **				(q_paddr) is just addr, and the
36 **				user & host are allocated internally
37 **				to parse.
38 **			0 -- copy out the parsed user & host, but
39 **				don't copy the printname.
40 **			+1 -- copy everything.
41 **		delim -- the character to terminate the address, passed
42 **			to prescan.
43 **		e -- the envelope that will contain this address.
44 **
45 **	Returns:
46 **		A pointer to the address descriptor header (`a' if
47 **			`a' is non-NULL).
48 **		NULL on error.
49 **
50 **	Side Effects:
51 **		none
52 */
53 
54 /* following delimiters are inherent to the internal algorithms */
55 # define DELIMCHARS	"\201()<>,;\\\"\r\n"	/* word delimiters */
56 
57 ADDRESS *
58 parseaddr(addr, a, copyf, delim, e)
59 	char *addr;
60 	register ADDRESS *a;
61 	int copyf;
62 	char delim;
63 	register ENVELOPE *e;
64 {
65 	register char **pvp;
66 	char pvpbuf[PSBUFSIZE];
67 	extern char **prescan();
68 	extern ADDRESS *buildaddr();
69 	extern bool invalidaddr();
70 
71 	/*
72 	**  Initialize and prescan address.
73 	*/
74 
75 	e->e_to = addr;
76 	if (tTd(20, 1))
77 		printf("\n--parseaddr(%s)\n", addr);
78 
79 	if (invalidaddr(addr))
80 	{
81 		if (tTd(20, 1))
82 			printf("parseaddr-->bad address\n");
83 		return NULL;
84 	}
85 
86 	pvp = prescan(addr, delim, pvpbuf);
87 	if (pvp == NULL)
88 	{
89 		if (tTd(20, 1))
90 			printf("parseaddr-->NULL\n");
91 		return (NULL);
92 	}
93 
94 	/*
95 	**  Apply rewriting rules.
96 	**	Ruleset 0 does basic parsing.  It must resolve.
97 	*/
98 
99 	rewrite(pvp, 3);
100 	rewrite(pvp, 0);
101 
102 	/*
103 	**  See if we resolved to a real mailer.
104 	*/
105 
106 	if ((pvp[0][0] & 0377) != CANONNET)
107 	{
108 		setstat(EX_USAGE);
109 		syserr("554 cannot resolve name");
110 		return (NULL);
111 	}
112 
113 	/*
114 	**  Build canonical address from pvp.
115 	*/
116 
117 	a = buildaddr(pvp, a);
118 	if (a == NULL)
119 		return (NULL);
120 
121 	/*
122 	**  Make local copies of the host & user and then
123 	**  transport them out.
124 	*/
125 
126 	allocaddr(a, copyf, addr);
127 
128 	/*
129 	**  Compute return value.
130 	*/
131 
132 	if (tTd(20, 1))
133 	{
134 		printf("parseaddr-->");
135 		printaddr(a, FALSE);
136 	}
137 
138 	return (a);
139 }
140 /*
141 **  INVALIDADDR -- check for address containing meta-characters
142 **
143 **	Parameters:
144 **		addr -- the address to check.
145 **
146 **	Returns:
147 **		TRUE -- if the address has any "wierd" characters
148 **		FALSE -- otherwise.
149 */
150 
151 bool
152 invalidaddr(addr)
153 	register char *addr;
154 {
155 	for (; *addr != '\0'; addr++)
156 	{
157 		if ((*addr & 0340) != 0200)
158 			continue;
159 		setstat(EX_USAGE);
160 		usrerr("553 Address contained invalid control characters");
161 		return TRUE;
162 	}
163 	return FALSE;
164 }
165 /*
166 **  ALLOCADDR -- do local allocations of address on demand.
167 **
168 **	Also lowercases the host name if requested.
169 **
170 **	Parameters:
171 **		a -- the address to reallocate.
172 **		copyf -- the copy flag (see parseaddr for description).
173 **		paddr -- the printname of the address.
174 **
175 **	Returns:
176 **		none.
177 **
178 **	Side Effects:
179 **		Copies portions of a into local buffers as requested.
180 */
181 
182 allocaddr(a, copyf, paddr)
183 	register ADDRESS *a;
184 	int copyf;
185 	char *paddr;
186 {
187 	register MAILER *m = a->q_mailer;
188 
189 	if (copyf > 0 && paddr != NULL)
190 	{
191 		extern char *DelimChar;
192 		char savec = *DelimChar;
193 
194 		*DelimChar = '\0';
195 		a->q_paddr = newstr(paddr);
196 		*DelimChar = savec;
197 	}
198 	else
199 		a->q_paddr = paddr;
200 
201 	if (a->q_user == NULL)
202 		a->q_user = "";
203 	if (a->q_host == NULL)
204 		a->q_host = "";
205 
206 	if (copyf >= 0)
207 	{
208 		a->q_host = newstr(a->q_host);
209 		if (a->q_user != a->q_paddr)
210 			a->q_user = newstr(a->q_user);
211 	}
212 
213 	if (a->q_paddr == NULL)
214 		a->q_paddr = a->q_user;
215 
216 	/*
217 	**  Convert host name to lower case if requested.
218 	**	User name will be done later.
219 	*/
220 
221 	if (!bitnset(M_HST_UPPER, m->m_flags))
222 		makelower(a->q_host);
223 }
224 /*
225 **  LOWERADDR -- map UPPER->lower case on addresses as requested.
226 **
227 **	Parameters:
228 **		a -- address to be mapped.
229 **
230 **	Returns:
231 **		none.
232 **
233 **	Side Effects:
234 **		none.
235 */
236 
237 loweraddr(a)
238 	register ADDRESS *a;
239 {
240 	register MAILER *m = a->q_mailer;
241 
242 	if (!bitnset(M_USR_UPPER, m->m_flags))
243 		makelower(a->q_user);
244 }
245 /*
246 **  PRESCAN -- Prescan name and make it canonical
247 **
248 **	Scans a name and turns it into a set of tokens.  This process
249 **	deletes blanks and comments (in parentheses).
250 **
251 **	This routine knows about quoted strings and angle brackets.
252 **
253 **	There are certain subtleties to this routine.  The one that
254 **	comes to mind now is that backslashes on the ends of names
255 **	are silently stripped off; this is intentional.  The problem
256 **	is that some versions of sndmsg (like at LBL) set the kill
257 **	character to something other than @ when reading addresses;
258 **	so people type "csvax.eric\@berkeley" -- which screws up the
259 **	berknet mailer.
260 **
261 **	Parameters:
262 **		addr -- the name to chomp.
263 **		delim -- the delimiter for the address, normally
264 **			'\0' or ','; \0 is accepted in any case.
265 **			If '\t' then we are reading the .cf file.
266 **		pvpbuf -- place to put the saved text -- note that
267 **			the pointers are static.
268 **
269 **	Returns:
270 **		A pointer to a vector of tokens.
271 **		NULL on error.
272 **
273 **	Side Effects:
274 **		sets DelimChar to point to the character matching 'delim'.
275 */
276 
277 /* states and character types */
278 # define OPR		0	/* operator */
279 # define ATM		1	/* atom */
280 # define QST		2	/* in quoted string */
281 # define SPC		3	/* chewing up spaces */
282 # define ONE		4	/* pick up one character */
283 
284 # define NSTATES	5	/* number of states */
285 # define TYPE		017	/* mask to select state type */
286 
287 /* meta bits for table */
288 # define M		020	/* meta character; don't pass through */
289 # define B		040	/* cause a break */
290 # define MB		M|B	/* meta-break */
291 
292 static short StateTab[NSTATES][NSTATES] =
293 {
294    /*	oldst	chtype>	OPR	ATM	QST	SPC	ONE	*/
295 	/*OPR*/		OPR|B,	ATM|B,	QST|B,	SPC|MB,	ONE|B,
296 	/*ATM*/		OPR|B,	ATM,	QST|B,	SPC|MB,	ONE|B,
297 	/*QST*/		QST,	QST,	OPR,	QST,	QST,
298 	/*SPC*/		OPR,	ATM,	QST,	SPC|M,	ONE,
299 	/*ONE*/		OPR,	OPR,	OPR,	OPR,	OPR,
300 };
301 
302 # define NOCHAR		-1	/* signal nothing in lookahead token */
303 
304 char	*DelimChar;		/* set to point to the delimiter */
305 
306 char **
307 prescan(addr, delim, pvpbuf)
308 	char *addr;
309 	char delim;
310 	char pvpbuf[];
311 {
312 	register char *p;
313 	register char *q;
314 	register int c;
315 	char **avp;
316 	bool bslashmode;
317 	int cmntcnt;
318 	int anglecnt;
319 	char *tok;
320 	int state;
321 	int newstate;
322 	static char *av[MAXATOM+1];
323 	extern int errno;
324 
325 	/* make sure error messages don't have garbage on them */
326 	errno = 0;
327 
328 	q = pvpbuf;
329 	bslashmode = FALSE;
330 	cmntcnt = 0;
331 	anglecnt = 0;
332 	avp = av;
333 	state = ATM;
334 	c = NOCHAR;
335 	p = addr;
336 	if (tTd(22, 11))
337 	{
338 		printf("prescan: ");
339 		xputs(p);
340 		(void) putchar('\n');
341 	}
342 
343 	do
344 	{
345 		/* read a token */
346 		tok = q;
347 		for (;;)
348 		{
349 			/* store away any old lookahead character */
350 			if (c != NOCHAR)
351 			{
352 				/* see if there is room */
353 				if (q >= &pvpbuf[PSBUFSIZE - 5])
354 				{
355 					usrerr("553 Address too long");
356 					DelimChar = p;
357 					return (NULL);
358 				}
359 
360 				/* squirrel it away */
361 				*q++ = c;
362 			}
363 
364 			/* read a new input character */
365 			c = *p++;
366 			if (c == '\0')
367 			{
368 				/* diagnose and patch up bad syntax */
369 				if (state == QST)
370 				{
371 					usrerr("553 Unbalanced '\"'");
372 					c = '"';
373 				}
374 				else if (cmntcnt > 0)
375 				{
376 					usrerr("553 Unbalanced '('");
377 					c = ')';
378 				}
379 				else if (anglecnt > 0)
380 				{
381 					c = '>';
382 					usrerr("553 Unbalanced '<'");
383 				}
384 				else
385 					break;
386 
387 				p--;
388 			}
389 			else if (c == delim && anglecnt <= 0 &&
390 					cmntcnt <= 0 && state != QST)
391 				break;
392 
393 			if (tTd(22, 101))
394 				printf("c=%c, s=%d; ", c, state);
395 
396 			/* chew up special characters */
397 			*q = '\0';
398 			if (bslashmode)
399 			{
400 				/* kludge \! for naive users */
401 				if (cmntcnt > 0)
402 					c = NOCHAR;
403 				else if (c != '!')
404 					*q++ = '\\';
405 				bslashmode = FALSE;
406 				continue;
407 			}
408 
409 			if (c == '\\')
410 			{
411 				bslashmode = TRUE;
412 				c = NOCHAR;
413 				continue;
414 			}
415 			else if (state == QST)
416 			{
417 				/* do nothing, just avoid next clauses */
418 			}
419 			else if (c == '(')
420 			{
421 				cmntcnt++;
422 				c = NOCHAR;
423 			}
424 			else if (c == ')')
425 			{
426 				if (cmntcnt <= 0)
427 				{
428 					usrerr("553 Unbalanced ')'");
429 					DelimChar = p;
430 					return (NULL);
431 				}
432 				else
433 					cmntcnt--;
434 			}
435 			else if (cmntcnt > 0)
436 				c = NOCHAR;
437 			else if (c == '<')
438 				anglecnt++;
439 			else if (c == '>')
440 			{
441 				if (anglecnt <= 0)
442 				{
443 					usrerr("553 Unbalanced '>'");
444 					DelimChar = p;
445 					return (NULL);
446 				}
447 				anglecnt--;
448 			}
449 			else if (delim == ' ' && isascii(c) && isspace(c))
450 				c = ' ';
451 
452 			if (c == NOCHAR)
453 				continue;
454 
455 			/* see if this is end of input */
456 			if (c == delim && anglecnt <= 0 && state != QST)
457 				break;
458 
459 			newstate = StateTab[state][toktype(c)];
460 			if (tTd(22, 101))
461 				printf("ns=%02o\n", newstate);
462 			state = newstate & TYPE;
463 			if (bitset(M, newstate))
464 				c = NOCHAR;
465 			if (bitset(B, newstate))
466 				break;
467 		}
468 
469 		/* new token */
470 		if (tok != q)
471 		{
472 			*q++ = '\0';
473 			if (tTd(22, 36))
474 			{
475 				printf("tok=");
476 				xputs(tok);
477 				(void) putchar('\n');
478 			}
479 			if (avp >= &av[MAXATOM])
480 			{
481 				syserr("553 prescan: too many tokens");
482 				DelimChar = p;
483 				return (NULL);
484 			}
485 			*avp++ = tok;
486 		}
487 	} while (c != '\0' && (c != delim || anglecnt > 0));
488 	*avp = NULL;
489 	DelimChar = --p;
490 	if (tTd(22, 12))
491 	{
492 		printf("prescan==>");
493 		printav(av);
494 	}
495 	if (av[0] != NULL)
496 		return (av);
497 	return (NULL);
498 }
499 /*
500 **  TOKTYPE -- return token type
501 **
502 **	Parameters:
503 **		c -- the character in question.
504 **
505 **	Returns:
506 **		Its type.
507 **
508 **	Side Effects:
509 **		none.
510 */
511 
512 toktype(c)
513 	register int c;
514 {
515 	static char buf[50];
516 	static bool firstime = TRUE;
517 
518 	if (firstime)
519 	{
520 		firstime = FALSE;
521 		expand("\201o", buf, &buf[sizeof buf - 1], CurEnv);
522 		(void) strcat(buf, DELIMCHARS);
523 	}
524 	c &= 0377;
525 	if (c == MATCHCLASS || c == MATCHREPL || c == MATCHNCLASS)
526 		return (ONE);
527 	if (c == '"')
528 		return (QST);
529 	if ((c & 0340) == 0200)
530 		return (OPR);
531 	if (!isascii(c))
532 		return (ATM);
533 	if (isspace(c) || c == ')')
534 		return (SPC);
535 	if (strchr(buf, c) != NULL)
536 		return (OPR);
537 	return (ATM);
538 }
539 /*
540 **  REWRITE -- apply rewrite rules to token vector.
541 **
542 **	This routine is an ordered production system.  Each rewrite
543 **	rule has a LHS (called the pattern) and a RHS (called the
544 **	rewrite); 'rwr' points the the current rewrite rule.
545 **
546 **	For each rewrite rule, 'avp' points the address vector we
547 **	are trying to match against, and 'pvp' points to the pattern.
548 **	If pvp points to a special match value (MATCHZANY, MATCHANY,
549 **	MATCHONE, MATCHCLASS, MATCHNCLASS) then the address in avp
550 **	matched is saved away in the match vector (pointed to by 'mvp').
551 **
552 **	When a match between avp & pvp does not match, we try to
553 **	back out.  If we back up over MATCHONE, MATCHCLASS, or MATCHNCLASS
554 **	we must also back out the match in mvp.  If we reach a
555 **	MATCHANY or MATCHZANY we just extend the match and start
556 **	over again.
557 **
558 **	When we finally match, we rewrite the address vector
559 **	and try over again.
560 **
561 **	Parameters:
562 **		pvp -- pointer to token vector.
563 **
564 **	Returns:
565 **		none.
566 **
567 **	Side Effects:
568 **		pvp is modified.
569 */
570 
571 struct match
572 {
573 	char	**first;	/* first token matched */
574 	char	**last;		/* last token matched */
575 };
576 
577 # define MAXMATCH	9	/* max params per rewrite */
578 
579 
580 rewrite(pvp, ruleset)
581 	char **pvp;
582 	int ruleset;
583 {
584 	register char *ap;		/* address pointer */
585 	register char *rp;		/* rewrite pointer */
586 	register char **avp;		/* address vector pointer */
587 	register char **rvp;		/* rewrite vector pointer */
588 	register struct match *mlp;	/* cur ptr into mlist */
589 	register struct rewrite *rwr;	/* pointer to current rewrite rule */
590 	struct match mlist[MAXMATCH];	/* stores match on LHS */
591 	char *npvp[MAXATOM+1];		/* temporary space for rebuild */
592 
593 	if (OpMode == MD_TEST || tTd(21, 2))
594 	{
595 		printf("rewrite: ruleset %2d   input:", ruleset);
596 		printav(pvp);
597 	}
598 	if (ruleset < 0 || ruleset >= MAXRWSETS)
599 	{
600 		syserr("554 rewrite: illegal ruleset number %d", ruleset);
601 		return;
602 	}
603 	if (pvp == NULL)
604 		return;
605 
606 	/*
607 	**  Run through the list of rewrite rules, applying
608 	**	any that match.
609 	*/
610 
611 	for (rwr = RewriteRules[ruleset]; rwr != NULL; )
612 	{
613 		int loopcount = 0;
614 
615 		if (tTd(21, 12))
616 		{
617 			printf("-----trying rule:");
618 			printav(rwr->r_lhs);
619 		}
620 
621 		/* try to match on this rule */
622 		mlp = mlist;
623 		rvp = rwr->r_lhs;
624 		avp = pvp;
625 		while ((ap = *avp) != NULL || *rvp != NULL)
626 		{
627 			if (++loopcount > 100)
628 			{
629 				syserr("554 Infinite loop in ruleset %d", ruleset);
630 				printf("workspace: ");
631 				printav(pvp);
632 				break;
633 			}
634 			rp = *rvp;
635 			if (tTd(21, 35))
636 			{
637 				printf("rp=");
638 				xputs(rp);
639 				printf(", ap=");
640 				xputs(ap);
641 				printf("\n");
642 			}
643 			if (rp == NULL)
644 			{
645 				/* end-of-pattern before end-of-address */
646 				goto backup;
647 			}
648 			if (ap == NULL && (*rp & 0377) != MATCHZANY &&
649 			    (*rp & 0377) != CANONHOST)
650 			{
651 				/* end-of-input */
652 				break;
653 			}
654 
655 			switch (*rp & 0377)
656 			{
657 				register STAB *s;
658 
659 			  case MATCHCLASS:
660 			  case MATCHNCLASS:
661 				/* match any token in (not in) a class */
662 				s = stab(ap, ST_CLASS, ST_FIND);
663 				if (s == NULL || !bitnset(rp[1], s->s_class))
664 				{
665 					if ((*rp & 0377) == MATCHCLASS)
666 						goto backup;
667 				}
668 				else if ((*rp & 0377) == MATCHNCLASS)
669 					goto backup;
670 
671 				/* explicit fall-through */
672 
673 			  case MATCHONE:
674 			  case MATCHANY:
675 				/* match exactly one token */
676 				mlp->first = avp;
677 				mlp->last = avp++;
678 				mlp++;
679 				break;
680 
681 			  case MATCHZANY:
682 				/* match zero or more tokens */
683 				mlp->first = avp;
684 				mlp->last = avp - 1;
685 				mlp++;
686 				break;
687 
688 			  case CANONHOST:
689 				/* match zero tokens */
690 				break;
691 
692 			  default:
693 				/* must have exact match */
694 				if (strcasecmp(rp, ap))
695 					goto backup;
696 				avp++;
697 				break;
698 			}
699 
700 			/* successful match on this token */
701 			rvp++;
702 			continue;
703 
704 		  backup:
705 			/* match failed -- back up */
706 			while (--rvp >= rwr->r_lhs)
707 			{
708 				rp = *rvp;
709 				if ((*rp & 0377) == MATCHANY ||
710 				    (*rp & 0377) == MATCHZANY)
711 				{
712 					/* extend binding and continue */
713 					avp = ++mlp[-1].last;
714 					avp++;
715 					rvp++;
716 					break;
717 				}
718 				avp--;
719 				if ((*rp & 0377) == MATCHONE ||
720 				    (*rp & 0377) == MATCHCLASS ||
721 				    (*rp & 0377) == MATCHNCLASS)
722 				{
723 					/* back out binding */
724 					mlp--;
725 				}
726 			}
727 
728 			if (rvp < rwr->r_lhs)
729 			{
730 				/* total failure to match */
731 				break;
732 			}
733 		}
734 
735 		/*
736 		**  See if we successfully matched
737 		*/
738 
739 		if (rvp < rwr->r_lhs || *rvp != NULL)
740 		{
741 			if (tTd(21, 10))
742 				printf("----- rule fails\n");
743 			rwr = rwr->r_next;
744 			continue;
745 		}
746 
747 		rvp = rwr->r_rhs;
748 		if (tTd(21, 12))
749 		{
750 			printf("-----rule matches:");
751 			printav(rvp);
752 		}
753 
754 		rp = *rvp;
755 		if ((*rp & 0377) == CANONUSER)
756 		{
757 			rvp++;
758 			rwr = rwr->r_next;
759 		}
760 		else if ((*rp & 0377) == CANONHOST)
761 		{
762 			rvp++;
763 			rwr = NULL;
764 		}
765 		else if ((*rp & 0377) == CANONNET)
766 			rwr = NULL;
767 
768 		/* substitute */
769 		for (avp = npvp; *rvp != NULL; rvp++)
770 		{
771 			register struct match *m;
772 			register char **pp;
773 
774 			rp = *rvp;
775 			if ((*rp & 0377) == MATCHREPL)
776 			{
777 				/* substitute from LHS */
778 				m = &mlist[rp[1] - '1'];
779 				if (m < mlist || m >= mlp)
780 				{
781 					syserr("554 rewrite: ruleset %d: replacement $%c out of bounds",
782 						ruleset, rp[1]);
783 					return;
784 				}
785 				if (tTd(21, 15))
786 				{
787 					printf("$%c:", rp[1]);
788 					pp = m->first;
789 					while (pp <= m->last)
790 					{
791 						printf(" %x=\"", *pp);
792 						(void) fflush(stdout);
793 						printf("%s\"", *pp++);
794 					}
795 					printf("\n");
796 				}
797 				pp = m->first;
798 				while (pp <= m->last)
799 				{
800 					if (avp >= &npvp[MAXATOM])
801 					{
802 						syserr("554 rewrite: expansion too long");
803 						return;
804 					}
805 					*avp++ = *pp++;
806 				}
807 			}
808 			else
809 			{
810 				/* vanilla replacement */
811 				if (avp >= &npvp[MAXATOM])
812 				{
813 	toolong:
814 					syserr("554 rewrite: expansion too long");
815 					return;
816 				}
817 				*avp++ = rp;
818 			}
819 		}
820 		*avp++ = NULL;
821 
822 		/*
823 		**  Check for any hostname/keyword lookups.
824 		*/
825 
826 		for (rvp = npvp; *rvp != NULL; rvp++)
827 		{
828 			char **hbrvp;
829 			char **xpvp;
830 			int trsize;
831 			char *olddelimchar;
832 			char *replac;
833 			int endtoken;
834 			STAB *map;
835 			char *mapname;
836 			char **key_rvp;
837 			char **arg_rvp;
838 			char **default_rvp;
839 			char buf[MAXNAME + 1];
840 			char *pvpb1[MAXATOM + 1];
841 			char *argvect[10];
842 			char pvpbuf[PSBUFSIZE];
843 			extern char *DelimChar;
844 
845 			if ((**rvp & 0377) != HOSTBEGIN &&
846 			    (**rvp & 0377) != LOOKUPBEGIN)
847 				continue;
848 
849 			/*
850 			**  Got a hostname/keyword lookup.
851 			**
852 			**	This could be optimized fairly easily.
853 			*/
854 
855 			hbrvp = rvp;
856 			if ((**rvp & 0377) == HOSTBEGIN)
857 			{
858 				endtoken = HOSTEND;
859 				mapname = "host";
860 			}
861 			else
862 			{
863 				endtoken = LOOKUPEND;
864 				mapname = *++rvp;
865 			}
866 			map = stab(mapname, ST_MAP, ST_FIND);
867 			if (map == NULL)
868 				syserr("554 rewrite: map %s not found", mapname);
869 
870 			/* extract the match part */
871 			key_rvp = ++rvp;
872 			default_rvp = NULL;
873 			arg_rvp = argvect;
874 			xpvp = NULL;
875 			replac = pvpbuf;
876 			while (*rvp != NULL && (**rvp & 0377) != endtoken)
877 			{
878 				int nodetype = **rvp & 0377;
879 
880 				if (nodetype != CANONHOST && nodetype != CANONUSER)
881 				{
882 					rvp++;
883 					continue;
884 				}
885 
886 				*rvp++ = NULL;
887 
888 				if (xpvp != NULL)
889 				{
890 					cataddr(xpvp, replac,
891 						&pvpbuf[sizeof pvpbuf] - replac,
892 						'\0');
893 					*++arg_rvp = replac;
894 					replac += strlen(replac) + 1;
895 					xpvp = NULL;
896 				}
897 				switch (nodetype)
898 				{
899 				  case CANONHOST:
900 					xpvp = rvp;
901 					break;
902 
903 				  case CANONUSER:
904 					default_rvp = rvp;
905 					break;
906 				}
907 			}
908 			if (*rvp != NULL)
909 				*rvp++ = NULL;
910 			if (xpvp != NULL)
911 			{
912 				cataddr(xpvp, replac,
913 					&pvpbuf[sizeof pvpbuf] - replac,
914 					'\0');
915 				*++arg_rvp = replac;
916 			}
917 			*++arg_rvp = NULL;
918 
919 			/* save the remainder of the input string */
920 			trsize = (int) (avp - rvp + 1) * sizeof *rvp;
921 			bcopy((char *) rvp, (char *) pvpb1, trsize);
922 
923 			/* look it up */
924 			cataddr(key_rvp, buf, sizeof buf, '\0');
925 			argvect[0] = buf;
926 			if (map != NULL && bitset(MF_VALID, map->s_map.map_flags))
927 			{
928 				int bsize = sizeof buf - 1;
929 
930 				if (map->s_map.map_app != NULL)
931 					bsize -= strlen(map->s_map.map_app);
932 				replac = (*map->s_map.map_class->map_lookup)(&map->s_map,
933 						buf, sizeof buf - 1, argvect);
934 				if (replac != NULL && map->s_map.map_app != NULL)
935 					strcat(replac, map->s_map.map_app);
936 			}
937 			else
938 				replac = NULL;
939 
940 			/* if no replacement, use default */
941 			if (replac == NULL && default_rvp != NULL)
942 			{
943 				char buf2[sizeof buf];
944 
945 				/* rewrite the default with % translations */
946 				cataddr(default_rvp, buf2, sizeof buf2, '\0');
947 				map_rewrite(buf2, sizeof buf2, buf, sizeof buf,
948 					argvect);
949 				replac = buf;
950 			}
951 
952 			if (replac == NULL)
953 			{
954 				xpvp = key_rvp;
955 			}
956 			else
957 			{
958 				/* scan the new replacement */
959 				olddelimchar = DelimChar;
960 				xpvp = prescan(replac, '\0', pvpbuf);
961 				DelimChar = olddelimchar;
962 				if (xpvp == NULL)
963 				{
964 					syserr("553 rewrite: cannot prescan map value: %s", replac);
965 					return;
966 				}
967 			}
968 
969 			/* append it to the token list */
970 			for (avp = hbrvp; *xpvp != NULL; xpvp++)
971 			{
972 				*avp++ = newstr(*xpvp);
973 				if (avp >= &npvp[MAXATOM])
974 					goto toolong;
975 			}
976 
977 			/* restore the old trailing information */
978 			for (xpvp = pvpb1; (*avp++ = *xpvp++) != NULL; )
979 				if (avp >= &npvp[MAXATOM])
980 					goto toolong;
981 
982 			break;
983 		}
984 
985 		/*
986 		**  Check for subroutine calls.
987 		*/
988 
989 		if (*npvp != NULL && (**npvp & 0377) == CALLSUBR)
990 		{
991 			bcopy((char *) &npvp[2], (char *) pvp,
992 				(int) (avp - npvp - 2) * sizeof *avp);
993 			if (tTd(21, 3))
994 				printf("-----callsubr %s\n", npvp[1]);
995 			rewrite(pvp, atoi(npvp[1]));
996 		}
997 		else
998 		{
999 			bcopy((char *) npvp, (char *) pvp,
1000 				(int) (avp - npvp) * sizeof *avp);
1001 		}
1002 		if (tTd(21, 4))
1003 		{
1004 			printf("rewritten as:");
1005 			printav(pvp);
1006 		}
1007 	}
1008 
1009 	if (OpMode == MD_TEST || tTd(21, 2))
1010 	{
1011 		printf("rewrite: ruleset %2d returns:", ruleset);
1012 		printav(pvp);
1013 	}
1014 }
1015 /*
1016 **  BUILDADDR -- build address from token vector.
1017 **
1018 **	Parameters:
1019 **		tv -- token vector.
1020 **		a -- pointer to address descriptor to fill.
1021 **			If NULL, one will be allocated.
1022 **
1023 **	Returns:
1024 **		NULL if there was an error.
1025 **		'a' otherwise.
1026 **
1027 **	Side Effects:
1028 **		fills in 'a'
1029 */
1030 
1031 struct errcodes
1032 {
1033 	char	*ec_name;		/* name of error code */
1034 	int	ec_code;		/* numeric code */
1035 } ErrorCodes[] =
1036 {
1037 	"usage",	EX_USAGE,
1038 	"nouser",	EX_NOUSER,
1039 	"nohost",	EX_NOHOST,
1040 	"unavailable",	EX_UNAVAILABLE,
1041 	"software",	EX_SOFTWARE,
1042 	"tempfail",	EX_TEMPFAIL,
1043 	"protocol",	EX_PROTOCOL,
1044 #ifdef EX_CONFIG
1045 	"config",	EX_CONFIG,
1046 #endif
1047 	NULL,		EX_UNAVAILABLE,
1048 };
1049 
1050 ADDRESS *
1051 buildaddr(tv, a)
1052 	register char **tv;
1053 	register ADDRESS *a;
1054 {
1055 	struct mailer **mp;
1056 	register struct mailer *m;
1057 	char *bp;
1058 	int spaceleft;
1059 	static char buf[MAXNAME];
1060 
1061 	if (a == NULL)
1062 		a = (ADDRESS *) xalloc(sizeof *a);
1063 	bzero((char *) a, sizeof *a);
1064 
1065 	/* figure out what net/mailer to use */
1066 	if ((**tv & 0377) != CANONNET)
1067 	{
1068 		syserr("554 buildaddr: no net");
1069 		return (NULL);
1070 	}
1071 	tv++;
1072 	if (!strcasecmp(*tv, "error"))
1073 	{
1074 		if ((**++tv & 0377) == CANONHOST)
1075 		{
1076 			register struct errcodes *ep;
1077 
1078 			if (isascii(**++tv) && isdigit(**tv))
1079 			{
1080 				setstat(atoi(*tv));
1081 			}
1082 			else
1083 			{
1084 				for (ep = ErrorCodes; ep->ec_name != NULL; ep++)
1085 					if (strcasecmp(ep->ec_name, *tv) == 0)
1086 						break;
1087 				setstat(ep->ec_code);
1088 			}
1089 			tv++;
1090 		}
1091 		if ((**tv & 0377) != CANONUSER)
1092 			syserr("554 buildaddr: error: no user");
1093 		cataddr(++tv, buf, sizeof buf, ' ');
1094 		stripquotes(buf);
1095 		usrerr(buf);
1096 		return (NULL);
1097 	}
1098 
1099 	for (mp = Mailer; (m = *mp++) != NULL; )
1100 	{
1101 		if (!strcasecmp(m->m_name, *tv))
1102 			break;
1103 	}
1104 	if (m == NULL)
1105 	{
1106 		syserr("554 buildaddr: unknown mailer %s", *tv);
1107 		return (NULL);
1108 	}
1109 	a->q_mailer = m;
1110 
1111 	/* figure out what host (if any) */
1112 	tv++;
1113 	if (!bitnset(M_LOCALMAILER, m->m_flags))
1114 	{
1115 		if ((**tv & 0377) != CANONHOST)
1116 		{
1117 			syserr("554 buildaddr: no host");
1118 			return (NULL);
1119 		}
1120 		bp = buf;
1121 		spaceleft = sizeof buf - 1;
1122 		while (*++tv != NULL && (**tv & 0377) != CANONUSER)
1123 		{
1124 			int i = strlen(*tv);
1125 
1126 			if (i > spaceleft)
1127 			{
1128 				/* out of space for this address */
1129 				if (spaceleft >= 0)
1130 					syserr("554 buildaddr: host too long (%.40s...)",
1131 						buf);
1132 				i = spaceleft;
1133 				spaceleft = 0;
1134 			}
1135 			if (i <= 0)
1136 				continue;
1137 			bcopy(*tv, bp, i);
1138 			bp += i;
1139 			spaceleft -= i;
1140 		}
1141 		*bp = '\0';
1142 		a->q_host = newstr(buf);
1143 	}
1144 	else
1145 		a->q_host = NULL;
1146 
1147 	/* figure out the user */
1148 	if (*tv == NULL || (**tv & 0377) != CANONUSER)
1149 	{
1150 		syserr("554 buildaddr: no user");
1151 		return (NULL);
1152 	}
1153 	tv++;
1154 
1155 	/* do special mapping for local mailer */
1156 	if (m == LocalMailer && *tv != NULL)
1157 	{
1158 		register char *p = *tv;
1159 
1160 		if (*p == '"')
1161 			p++;
1162 		if (*p == '|')
1163 			a->q_mailer = m = ProgMailer;
1164 		else if (*p == '/')
1165 			a->q_mailer = m = FileMailer;
1166 		else if (*p == ':')
1167 		{
1168 			/* may be :include: */
1169 			cataddr(tv, buf, sizeof buf, '\0');
1170 			stripquotes(buf);
1171 			if (strncasecmp(buf, ":include:", 9) == 0)
1172 			{
1173 				/* if :include:, don't need further rewriting */
1174 				a->q_mailer = m = InclMailer;
1175 				a->q_user = &buf[9];
1176 				return (a);
1177 			}
1178 		}
1179 	}
1180 
1181 	if (m == LocalMailer && *tv != NULL && strcmp(*tv, "@") == 0)
1182 	{
1183 		tv++;
1184 		a->q_flags |= QNOTREMOTE;
1185 	}
1186 
1187 	/* rewrite according recipient mailer rewriting rules */
1188 	rewrite(tv, 2);
1189 	if (m->m_re_rwset > 0)
1190 		rewrite(tv, m->m_re_rwset);
1191 	rewrite(tv, 4);
1192 
1193 	/* save the result for the command line/RCPT argument */
1194 	cataddr(tv, buf, sizeof buf, '\0');
1195 	a->q_user = buf;
1196 
1197 	return (a);
1198 }
1199 /*
1200 **  CATADDR -- concatenate pieces of addresses (putting in <LWSP> subs)
1201 **
1202 **	Parameters:
1203 **		pvp -- parameter vector to rebuild.
1204 **		buf -- buffer to build the string into.
1205 **		sz -- size of buf.
1206 **		spacesub -- the space separator character; if null,
1207 **			use SpaceSub.
1208 **
1209 **	Returns:
1210 **		none.
1211 **
1212 **	Side Effects:
1213 **		Destroys buf.
1214 */
1215 
1216 cataddr(pvp, buf, sz, spacesub)
1217 	char **pvp;
1218 	char *buf;
1219 	register int sz;
1220 	char spacesub;
1221 {
1222 	bool oatomtok = FALSE;
1223 	bool natomtok = FALSE;
1224 	register int i;
1225 	register char *p;
1226 
1227 	if (spacesub == '\0')
1228 		spacesub = SpaceSub;
1229 
1230 	if (pvp == NULL)
1231 	{
1232 		(void) strcpy(buf, "");
1233 		return;
1234 	}
1235 	p = buf;
1236 	sz -= 2;
1237 	while (*pvp != NULL && (i = strlen(*pvp)) < sz)
1238 	{
1239 		natomtok = (toktype(**pvp) == ATM);
1240 		if (oatomtok && natomtok)
1241 			*p++ = spacesub;
1242 		(void) strcpy(p, *pvp);
1243 		oatomtok = natomtok;
1244 		p += i;
1245 		sz -= i + 1;
1246 		pvp++;
1247 	}
1248 	*p = '\0';
1249 }
1250 /*
1251 **  SAMEADDR -- Determine if two addresses are the same
1252 **
1253 **	This is not just a straight comparison -- if the mailer doesn't
1254 **	care about the host we just ignore it, etc.
1255 **
1256 **	Parameters:
1257 **		a, b -- pointers to the internal forms to compare.
1258 **
1259 **	Returns:
1260 **		TRUE -- they represent the same mailbox.
1261 **		FALSE -- they don't.
1262 **
1263 **	Side Effects:
1264 **		none.
1265 */
1266 
1267 bool
1268 sameaddr(a, b)
1269 	register ADDRESS *a;
1270 	register ADDRESS *b;
1271 {
1272 	/* if they don't have the same mailer, forget it */
1273 	if (a->q_mailer != b->q_mailer)
1274 		return (FALSE);
1275 
1276 	/* if the user isn't the same, we can drop out */
1277 	if (strcmp(a->q_user, b->q_user) != 0)
1278 		return (FALSE);
1279 
1280 	/* if the mailer ignores hosts, we have succeeded! */
1281 	if (bitnset(M_LOCALMAILER, a->q_mailer->m_flags))
1282 		return (TRUE);
1283 
1284 	/* otherwise compare hosts (but be careful for NULL ptrs) */
1285 	if (a->q_host == NULL || b->q_host == NULL)
1286 		return (FALSE);
1287 	if (strcmp(a->q_host, b->q_host) != 0)
1288 		return (FALSE);
1289 
1290 	return (TRUE);
1291 }
1292 /*
1293 **  PRINTADDR -- print address (for debugging)
1294 **
1295 **	Parameters:
1296 **		a -- the address to print
1297 **		follow -- follow the q_next chain.
1298 **
1299 **	Returns:
1300 **		none.
1301 **
1302 **	Side Effects:
1303 **		none.
1304 */
1305 
1306 printaddr(a, follow)
1307 	register ADDRESS *a;
1308 	bool follow;
1309 {
1310 	bool first = TRUE;
1311 	register MAILER *m;
1312 	MAILER pseudomailer;
1313 
1314 	while (a != NULL)
1315 	{
1316 		first = FALSE;
1317 		printf("%x=", a);
1318 		(void) fflush(stdout);
1319 
1320 		/* find the mailer -- carefully */
1321 		m = a->q_mailer;
1322 		if (m == NULL)
1323 		{
1324 			m = &pseudomailer;
1325 			m->m_mno = -1;
1326 			m->m_name = "NULL";
1327 		}
1328 
1329 		printf("%s: mailer %d (%s), host `%s', user `%s', ruser `%s'\n",
1330 		       a->q_paddr, m->m_mno, m->m_name,
1331 		       a->q_host, a->q_user, a->q_ruser? a->q_ruser: "<null>");
1332 		printf("\tnext=%x, flags=%o, alias %x\n", a->q_next, a->q_flags,
1333 		       a->q_alias);
1334 		printf("\thome=\"%s\", fullname=\"%s\"\n", a->q_home,
1335 		       a->q_fullname);
1336 
1337 		if (!follow)
1338 			return;
1339 		a = a->q_next;
1340 	}
1341 	if (first)
1342 		printf("[NULL]\n");
1343 }
1344 
1345 /*
1346 **  REMOTENAME -- return the name relative to the current mailer
1347 **
1348 **	Parameters:
1349 **		name -- the name to translate.
1350 **		m -- the mailer that we want to do rewriting relative
1351 **			to.
1352 **		senderaddress -- if set, uses the sender rewriting rules
1353 **			rather than the recipient rewriting rules.
1354 **		header -- set if this address is in the header, rather
1355 **			than an envelope header.
1356 **		canonical -- if set, strip out any comment information,
1357 **			etc.
1358 **		e -- the current envelope.
1359 **
1360 **	Returns:
1361 **		the text string representing this address relative to
1362 **			the receiving mailer.
1363 **
1364 **	Side Effects:
1365 **		none.
1366 **
1367 **	Warnings:
1368 **		The text string returned is tucked away locally;
1369 **			copy it if you intend to save it.
1370 */
1371 
1372 char *
1373 remotename(name, m, senderaddress, header, canonical, e)
1374 	char *name;
1375 	struct mailer *m;
1376 	bool senderaddress;
1377 	bool header;
1378 	bool canonical;
1379 	register ENVELOPE *e;
1380 {
1381 	register char **pvp;
1382 	char *fancy;
1383 	extern char *macvalue();
1384 	char *oldg = macvalue('g', e);
1385 	int rwset;
1386 	static char buf[MAXNAME];
1387 	char lbuf[MAXNAME];
1388 	char pvpbuf[PSBUFSIZE];
1389 	extern char **prescan();
1390 	extern char *crackaddr();
1391 
1392 	if (tTd(12, 1))
1393 		printf("remotename(%s)\n", name);
1394 
1395 	/* don't do anything if we are tagging it as special */
1396 	if (senderaddress)
1397 		rwset = header ? m->m_sh_rwset : m->m_se_rwset;
1398 	else
1399 		rwset = header ? m->m_rh_rwset : m->m_re_rwset;
1400 	if (rwset < 0)
1401 		return (name);
1402 
1403 	/*
1404 	**  Do a heuristic crack of this name to extract any comment info.
1405 	**	This will leave the name as a comment and a $g macro.
1406 	*/
1407 
1408 	if (canonical || bitnset(M_NOCOMMENT, m->m_flags))
1409 		fancy = "\201g";
1410 	else
1411 		fancy = crackaddr(name);
1412 
1413 	/*
1414 	**  Turn the name into canonical form.
1415 	**	Normally this will be RFC 822 style, i.e., "user@domain".
1416 	**	If this only resolves to "user", and the "C" flag is
1417 	**	specified in the sending mailer, then the sender's
1418 	**	domain will be appended.
1419 	*/
1420 
1421 	pvp = prescan(name, '\0', pvpbuf);
1422 	if (pvp == NULL)
1423 		return (name);
1424 	rewrite(pvp, 3);
1425 	if (e->e_fromdomain != NULL)
1426 	{
1427 		/* append from domain to this address */
1428 		register char **pxp = pvp;
1429 
1430 		/* see if there is an "@domain" in the current name */
1431 		while (*pxp != NULL && strcmp(*pxp, "@") != 0)
1432 			pxp++;
1433 		if (*pxp == NULL)
1434 		{
1435 			/* no.... append the "@domain" from the sender */
1436 			register char **qxq = e->e_fromdomain;
1437 
1438 			while ((*pxp++ = *qxq++) != NULL)
1439 				continue;
1440 			rewrite(pvp, 3);
1441 		}
1442 	}
1443 
1444 	/*
1445 	**  Do more specific rewriting.
1446 	**	Rewrite using ruleset 1 or 2 depending on whether this is
1447 	**		a sender address or not.
1448 	**	Then run it through any receiving-mailer-specific rulesets.
1449 	*/
1450 
1451 	if (senderaddress)
1452 		rewrite(pvp, 1);
1453 	else
1454 		rewrite(pvp, 2);
1455 	if (rwset > 0)
1456 		rewrite(pvp, rwset);
1457 
1458 	/*
1459 	**  Do any final sanitation the address may require.
1460 	**	This will normally be used to turn internal forms
1461 	**	(e.g., user@host.LOCAL) into external form.  This
1462 	**	may be used as a default to the above rules.
1463 	*/
1464 
1465 	rewrite(pvp, 4);
1466 
1467 	/*
1468 	**  Now restore the comment information we had at the beginning.
1469 	*/
1470 
1471 	cataddr(pvp, lbuf, sizeof lbuf, '\0');
1472 	define('g', lbuf, e);
1473 	expand(fancy, buf, &buf[sizeof buf - 1], e);
1474 	define('g', oldg, e);
1475 
1476 	if (tTd(12, 1))
1477 		printf("remotename => `%s'\n", buf);
1478 	return (buf);
1479 }
1480 /*
1481 **  MAPLOCALUSER -- run local username through ruleset 5 for final redirection
1482 **
1483 **	Parameters:
1484 **		a -- the address to map (but just the user name part).
1485 **		sendq -- the sendq in which to install any replacement
1486 **			addresses.
1487 **
1488 **	Returns:
1489 **		none.
1490 */
1491 
1492 maplocaluser(a, sendq, e)
1493 	register ADDRESS *a;
1494 	ADDRESS **sendq;
1495 	ENVELOPE *e;
1496 {
1497 	register char **pvp;
1498 	register ADDRESS *a1 = NULL;
1499 	char pvpbuf[PSBUFSIZE];
1500 
1501 	if (tTd(29, 1))
1502 	{
1503 		printf("maplocaluser: ");
1504 		printaddr(a, FALSE);
1505 	}
1506 	pvp = prescan(a->q_user, '\0', pvpbuf);
1507 	if (pvp == NULL)
1508 		return;
1509 
1510 	rewrite(pvp, 5);
1511 	if (pvp[0] == NULL || (pvp[0][0] & 0377) != CANONNET)
1512 		return;
1513 
1514 	/* if non-null, mailer destination specified -- has it changed? */
1515 	a1 = buildaddr(pvp, NULL);
1516 	if (a1 == NULL || sameaddr(a, a1))
1517 		return;
1518 
1519 	/* mark old address as dead; insert new address */
1520 	a->q_flags |= QDONTSEND;
1521 	if (tTd(29, 5))
1522 	{
1523 		printf("maplocaluser: QDONTSEND ");
1524 		printaddr(a, FALSE);
1525 	}
1526 	a1->q_alias = a;
1527 	allocaddr(a1, 1, NULL);
1528 	(void) recipient(a1, sendq, e);
1529 }
1530