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	6.9 (Berkeley) 01/20/93";
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	"\001()<>,;\\\"\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] != CANONNET)
107 	{
108 		setstat(EX_USAGE);
109 		usrerr("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 (!isascii((int) *addr & 0377) ||
158 		    !iscntrl(*addr) || isspace(*addr))
159 			continue;
160 		setstat(EX_USAGE);
161 		usrerr("Address contained invalid control characters");
162 		return TRUE;
163 	}
164 	return FALSE;
165 }
166 /*
167 **  ALLOCADDR -- do local allocations of address on demand.
168 **
169 **	Also lowercases the host name if requested.
170 **
171 **	Parameters:
172 **		a -- the address to reallocate.
173 **		copyf -- the copy flag (see parseaddr for description).
174 **		paddr -- the printname of the address.
175 **
176 **	Returns:
177 **		none.
178 **
179 **	Side Effects:
180 **		Copies portions of a into local buffers as requested.
181 */
182 
183 allocaddr(a, copyf, paddr)
184 	register ADDRESS *a;
185 	int copyf;
186 	char *paddr;
187 {
188 	register MAILER *m = a->q_mailer;
189 
190 	if (copyf > 0 && paddr != NULL)
191 	{
192 		extern char *DelimChar;
193 		char savec = *DelimChar;
194 
195 		*DelimChar = '\0';
196 		a->q_paddr = newstr(paddr);
197 		*DelimChar = savec;
198 	}
199 	else
200 		a->q_paddr = paddr;
201 
202 	if (a->q_user == NULL)
203 		a->q_user = "";
204 	if (a->q_host == NULL)
205 		a->q_host = "";
206 
207 	if (copyf >= 0)
208 	{
209 		a->q_host = newstr(a->q_host);
210 		if (a->q_user != a->q_paddr)
211 			a->q_user = newstr(a->q_user);
212 	}
213 
214 	if (a->q_paddr == NULL)
215 		a->q_paddr = a->q_user;
216 
217 	/*
218 	**  Convert host name to lower case if requested.
219 	**	User name will be done later.
220 	*/
221 
222 	if (!bitnset(M_HST_UPPER, m->m_flags))
223 		makelower(a->q_host);
224 }
225 /*
226 **  LOWERADDR -- map UPPER->lower case on addresses as requested.
227 **
228 **	Parameters:
229 **		a -- address to be mapped.
230 **
231 **	Returns:
232 **		none.
233 **
234 **	Side Effects:
235 **		none.
236 */
237 
238 loweraddr(a)
239 	register ADDRESS *a;
240 {
241 	register MAILER *m = a->q_mailer;
242 
243 	if (!bitnset(M_USR_UPPER, m->m_flags))
244 		makelower(a->q_user);
245 }
246 /*
247 **  PRESCAN -- Prescan name and make it canonical
248 **
249 **	Scans a name and turns it into a set of tokens.  This process
250 **	deletes blanks and comments (in parentheses).
251 **
252 **	This routine knows about quoted strings and angle brackets.
253 **
254 **	There are certain subtleties to this routine.  The one that
255 **	comes to mind now is that backslashes on the ends of names
256 **	are silently stripped off; this is intentional.  The problem
257 **	is that some versions of sndmsg (like at LBL) set the kill
258 **	character to something other than @ when reading addresses;
259 **	so people type "csvax.eric\@berkeley" -- which screws up the
260 **	berknet mailer.
261 **
262 **	Parameters:
263 **		addr -- the name to chomp.
264 **		delim -- the delimiter for the address, normally
265 **			'\0' or ','; \0 is accepted in any case.
266 **			If '\t' then we are reading the .cf file.
267 **		pvpbuf -- place to put the saved text -- note that
268 **			the pointers are static.
269 **
270 **	Returns:
271 **		A pointer to a vector of tokens.
272 **		NULL on error.
273 **
274 **	Side Effects:
275 **		sets DelimChar to point to the character matching 'delim'.
276 */
277 
278 /* states and character types */
279 # define OPR		0	/* operator */
280 # define ATM		1	/* atom */
281 # define QST		2	/* in quoted string */
282 # define SPC		3	/* chewing up spaces */
283 # define ONE		4	/* pick up one character */
284 
285 # define NSTATES	5	/* number of states */
286 # define TYPE		017	/* mask to select state type */
287 
288 /* meta bits for table */
289 # define M		020	/* meta character; don't pass through */
290 # define B		040	/* cause a break */
291 # define MB		M|B	/* meta-break */
292 
293 static short StateTab[NSTATES][NSTATES] =
294 {
295    /*	oldst	chtype>	OPR	ATM	QST	SPC	ONE	*/
296 	/*OPR*/		OPR|B,	ATM|B,	QST|B,	SPC|MB,	ONE|B,
297 	/*ATM*/		OPR|B,	ATM,	QST|B,	SPC|MB,	ONE|B,
298 	/*QST*/		QST,	QST,	OPR,	QST,	QST,
299 	/*SPC*/		OPR,	ATM,	QST,	SPC|M,	ONE,
300 	/*ONE*/		OPR,	OPR,	OPR,	OPR,	OPR,
301 };
302 
303 # define NOCHAR		-1	/* signal nothing in lookahead token */
304 
305 char	*DelimChar;		/* set to point to the delimiter */
306 
307 char **
308 prescan(addr, delim, pvpbuf)
309 	char *addr;
310 	char delim;
311 	char pvpbuf[];
312 {
313 	register char *p;
314 	register char *q;
315 	register int c;
316 	char **avp;
317 	bool bslashmode;
318 	int cmntcnt;
319 	int anglecnt;
320 	char *tok;
321 	int state;
322 	int newstate;
323 	static char *av[MAXATOM+1];
324 	extern int errno;
325 
326 	/* make sure error messages don't have garbage on them */
327 	errno = 0;
328 
329 	q = pvpbuf;
330 	bslashmode = FALSE;
331 	cmntcnt = 0;
332 	anglecnt = 0;
333 	avp = av;
334 	state = ATM;
335 	c = NOCHAR;
336 	p = addr;
337 	if (tTd(22, 11))
338 	{
339 		printf("prescan: ");
340 		xputs(p);
341 		(void) putchar('\n');
342 	}
343 
344 	do
345 	{
346 		/* read a token */
347 		tok = q;
348 		for (;;)
349 		{
350 			/* store away any old lookahead character */
351 			if (c != NOCHAR)
352 			{
353 				/* see if there is room */
354 				if (q >= &pvpbuf[PSBUFSIZE - 5])
355 				{
356 					usrerr("Address too long");
357 					DelimChar = p;
358 					return (NULL);
359 				}
360 
361 				/* squirrel it away */
362 				*q++ = c;
363 			}
364 
365 			/* read a new input character */
366 			c = *p++;
367 			if (c == '\0')
368 			{
369 				/* diagnose and patch up bad syntax */
370 				if (state == QST)
371 				{
372 					usrerr("Unbalanced '\"'");
373 					c = '"';
374 				}
375 				else if (cmntcnt > 0)
376 				{
377 					usrerr("Unbalanced '('");
378 					c = ')';
379 				}
380 				else if (anglecnt > 0)
381 				{
382 					c = '>';
383 					usrerr("Unbalanced '<'");
384 				}
385 				else
386 					break;
387 
388 				p--;
389 			}
390 			else if (c == delim && anglecnt <= 0 &&
391 					cmntcnt <= 0 && state != QST)
392 				break;
393 
394 			if (tTd(22, 101))
395 				printf("c=%c, s=%d; ", c, state);
396 
397 			/* chew up special characters */
398 			*q = '\0';
399 			if (bslashmode)
400 			{
401 				/* kludge \! for naive users */
402 				if (c != '!')
403 					*q++ = '\\';
404 				bslashmode = FALSE;
405 				continue;
406 			}
407 
408 			if (c == '\\')
409 			{
410 				bslashmode = TRUE;
411 				c = NOCHAR;
412 				continue;
413 			}
414 			else if (state == QST)
415 			{
416 				/* do nothing, just avoid next clauses */
417 			}
418 			else if (c == '(')
419 			{
420 				cmntcnt++;
421 				c = NOCHAR;
422 			}
423 			else if (c == ')')
424 			{
425 				if (cmntcnt <= 0)
426 				{
427 					usrerr("Unbalanced ')'");
428 					DelimChar = p;
429 					return (NULL);
430 				}
431 				else
432 					cmntcnt--;
433 			}
434 			else if (cmntcnt > 0)
435 				c = NOCHAR;
436 			else if (c == '<')
437 				anglecnt++;
438 			else if (c == '>')
439 			{
440 				if (anglecnt <= 0)
441 				{
442 					usrerr("Unbalanced '>'");
443 					DelimChar = p;
444 					return (NULL);
445 				}
446 				anglecnt--;
447 			}
448 			else if (delim == ' ' && isspace(c))
449 				c = ' ';
450 
451 			if (c == NOCHAR)
452 				continue;
453 
454 			/* see if this is end of input */
455 			if (c == delim && anglecnt <= 0 && state != QST)
456 				break;
457 
458 			newstate = StateTab[state][toktype(c)];
459 			if (tTd(22, 101))
460 				printf("ns=%02o\n", newstate);
461 			state = newstate & TYPE;
462 			if (bitset(M, newstate))
463 				c = NOCHAR;
464 			if (bitset(B, newstate))
465 				break;
466 		}
467 
468 		/* new token */
469 		if (tok != q)
470 		{
471 			*q++ = '\0';
472 			if (tTd(22, 36))
473 			{
474 				printf("tok=");
475 				xputs(tok);
476 				(void) putchar('\n');
477 			}
478 			if (avp >= &av[MAXATOM])
479 			{
480 				syserr("prescan: too many tokens");
481 				DelimChar = p;
482 				return (NULL);
483 			}
484 			*avp++ = tok;
485 		}
486 	} while (c != '\0' && (c != delim || anglecnt > 0));
487 	*avp = NULL;
488 	DelimChar = --p;
489 	if (tTd(22, 12))
490 	{
491 		printf("prescan==>");
492 		printav(av);
493 	}
494 	if (av[0] != NULL)
495 		return (av);
496 	return (NULL);
497 }
498 /*
499 **  TOKTYPE -- return token type
500 **
501 **	Parameters:
502 **		c -- the character in question.
503 **
504 **	Returns:
505 **		Its type.
506 **
507 **	Side Effects:
508 **		none.
509 */
510 
511 toktype(c)
512 	register char c;
513 {
514 	static char buf[50];
515 	static bool firstime = TRUE;
516 
517 	if (firstime)
518 	{
519 		firstime = FALSE;
520 		expand("\001o", buf, &buf[sizeof buf - 1], CurEnv);
521 		(void) strcat(buf, DELIMCHARS);
522 	}
523 	if (c == MATCHCLASS || c == MATCHREPL || c == MATCHNCLASS)
524 		return (ONE);
525 	if (c == '"')
526 		return (QST);
527 	if (!isascii(c))
528 		return (ATM);
529 	if (isspace(c) || c == ')')
530 		return (SPC);
531 	if (iscntrl(c) || strchr(buf, c) != NULL)
532 		return (OPR);
533 	return (ATM);
534 }
535 /*
536 **  REWRITE -- apply rewrite rules to token vector.
537 **
538 **	This routine is an ordered production system.  Each rewrite
539 **	rule has a LHS (called the pattern) and a RHS (called the
540 **	rewrite); 'rwr' points the the current rewrite rule.
541 **
542 **	For each rewrite rule, 'avp' points the address vector we
543 **	are trying to match against, and 'pvp' points to the pattern.
544 **	If pvp points to a special match value (MATCHZANY, MATCHANY,
545 **	MATCHONE, MATCHCLASS, MATCHNCLASS) then the address in avp
546 **	matched is saved away in the match vector (pointed to by 'mvp').
547 **
548 **	When a match between avp & pvp does not match, we try to
549 **	back out.  If we back up over MATCHONE, MATCHCLASS, or MATCHNCLASS
550 **	we must also back out the match in mvp.  If we reach a
551 **	MATCHANY or MATCHZANY we just extend the match and start
552 **	over again.
553 **
554 **	When we finally match, we rewrite the address vector
555 **	and try over again.
556 **
557 **	Parameters:
558 **		pvp -- pointer to token vector.
559 **
560 **	Returns:
561 **		none.
562 **
563 **	Side Effects:
564 **		pvp is modified.
565 */
566 
567 struct match
568 {
569 	char	**first;	/* first token matched */
570 	char	**last;		/* last token matched */
571 };
572 
573 # define MAXMATCH	9	/* max params per rewrite */
574 
575 
576 rewrite(pvp, ruleset)
577 	char **pvp;
578 	int ruleset;
579 {
580 	register char *ap;		/* address pointer */
581 	register char *rp;		/* rewrite pointer */
582 	register char **avp;		/* address vector pointer */
583 	register char **rvp;		/* rewrite vector pointer */
584 	register struct match *mlp;	/* cur ptr into mlist */
585 	register struct rewrite *rwr;	/* pointer to current rewrite rule */
586 	struct match mlist[MAXMATCH];	/* stores match on LHS */
587 	char *npvp[MAXATOM+1];		/* temporary space for rebuild */
588 
589 	if (OpMode == MD_TEST || tTd(21, 2))
590 	{
591 		printf("rewrite: ruleset %2d   input:", ruleset);
592 		printav(pvp);
593 	}
594 	if (ruleset < 0 || ruleset >= MAXRWSETS)
595 	{
596 		syserr("rewrite: illegal ruleset number %d", ruleset);
597 		return;
598 	}
599 	if (pvp == NULL)
600 		return;
601 
602 	/*
603 	**  Run through the list of rewrite rules, applying
604 	**	any that match.
605 	*/
606 
607 	for (rwr = RewriteRules[ruleset]; rwr != NULL; )
608 	{
609 		int loopcount = 0;
610 
611 		if (tTd(21, 12))
612 		{
613 			printf("-----trying rule:");
614 			printav(rwr->r_lhs);
615 		}
616 
617 		/* try to match on this rule */
618 		mlp = mlist;
619 		rvp = rwr->r_lhs;
620 		avp = pvp;
621 		while ((ap = *avp) != NULL || *rvp != NULL)
622 		{
623 			if (++loopcount > 100)
624 			{
625 				syserr("Infinite loop in ruleset %d", ruleset);
626 				printf("workspace: ");
627 				printav(pvp);
628 				break;
629 			}
630 			rp = *rvp;
631 			if (tTd(21, 35))
632 			{
633 				printf("rp=");
634 				xputs(rp);
635 				printf(", ap=");
636 				xputs(ap);
637 				printf("\n");
638 			}
639 			if (rp == NULL)
640 			{
641 				/* end-of-pattern before end-of-address */
642 				goto backup;
643 			}
644 			if (ap == NULL && *rp != MATCHZANY)
645 			{
646 				/* end-of-input */
647 				break;
648 			}
649 
650 			switch (*rp)
651 			{
652 				register STAB *s;
653 
654 			  case MATCHCLASS:
655 			  case MATCHNCLASS:
656 				/* match any token in (not in) a class */
657 				s = stab(ap, ST_CLASS, ST_FIND);
658 				if (s == NULL || !bitnset(rp[1], s->s_class))
659 				{
660 					if (*rp == MATCHCLASS)
661 						goto backup;
662 				}
663 				else if (*rp == MATCHNCLASS)
664 					goto backup;
665 
666 				/* explicit fall-through */
667 
668 			  case MATCHONE:
669 			  case MATCHANY:
670 				/* match exactly one token */
671 				mlp->first = avp;
672 				mlp->last = avp++;
673 				mlp++;
674 				break;
675 
676 			  case MATCHZANY:
677 				/* match zero or more tokens */
678 				mlp->first = avp;
679 				mlp->last = avp - 1;
680 				mlp++;
681 				break;
682 
683 			  default:
684 				/* must have exact match */
685 				if (strcasecmp(rp, ap))
686 					goto backup;
687 				avp++;
688 				break;
689 			}
690 
691 			/* successful match on this token */
692 			rvp++;
693 			continue;
694 
695 		  backup:
696 			/* match failed -- back up */
697 			while (--rvp >= rwr->r_lhs)
698 			{
699 				rp = *rvp;
700 				if (*rp == MATCHANY || *rp == MATCHZANY)
701 				{
702 					/* extend binding and continue */
703 					avp = ++mlp[-1].last;
704 					avp++;
705 					rvp++;
706 					break;
707 				}
708 				avp--;
709 				if (*rp == MATCHONE || *rp == MATCHCLASS ||
710 				    *rp == MATCHNCLASS)
711 				{
712 					/* back out binding */
713 					mlp--;
714 				}
715 			}
716 
717 			if (rvp < rwr->r_lhs)
718 			{
719 				/* total failure to match */
720 				break;
721 			}
722 		}
723 
724 		/*
725 		**  See if we successfully matched
726 		*/
727 
728 		if (rvp < rwr->r_lhs || *rvp != NULL)
729 		{
730 			if (tTd(21, 10))
731 				printf("----- rule fails\n");
732 			rwr = rwr->r_next;
733 			continue;
734 		}
735 
736 		rvp = rwr->r_rhs;
737 		if (tTd(21, 12))
738 		{
739 			printf("-----rule matches:");
740 			printav(rvp);
741 		}
742 
743 		rp = *rvp;
744 		if (*rp == CANONUSER)
745 		{
746 			rvp++;
747 			rwr = rwr->r_next;
748 		}
749 		else if (*rp == CANONHOST)
750 		{
751 			rvp++;
752 			rwr = NULL;
753 		}
754 		else if (*rp == CANONNET)
755 			rwr = NULL;
756 
757 		/* substitute */
758 		for (avp = npvp; *rvp != NULL; rvp++)
759 		{
760 			register struct match *m;
761 			register char **pp;
762 
763 			rp = *rvp;
764 			if (*rp == MATCHREPL)
765 			{
766 				/* substitute from LHS */
767 				m = &mlist[rp[1] - '1'];
768 				if (m < mlist || m >= mlp)
769 				{
770 					syserr("rewrite: ruleset %d: replacement $%c out of bounds",
771 						ruleset, rp[1]);
772 					return;
773 				}
774 				if (tTd(21, 15))
775 				{
776 					printf("$%c:", rp[1]);
777 					pp = m->first;
778 					while (pp <= m->last)
779 					{
780 						printf(" %x=\"", *pp);
781 						(void) fflush(stdout);
782 						printf("%s\"", *pp++);
783 					}
784 					printf("\n");
785 				}
786 				pp = m->first;
787 				while (pp <= m->last)
788 				{
789 					if (avp >= &npvp[MAXATOM])
790 					{
791 						syserr("rewrite: expansion too long");
792 						return;
793 					}
794 					*avp++ = *pp++;
795 				}
796 			}
797 			else
798 			{
799 				/* vanilla replacement */
800 				if (avp >= &npvp[MAXATOM])
801 				{
802 	toolong:
803 					syserr("rewrite: expansion too long");
804 					return;
805 				}
806 				*avp++ = rp;
807 			}
808 		}
809 		*avp++ = NULL;
810 
811 		/*
812 		**  Check for any hostname/keyword lookups.
813 		*/
814 
815 		for (rvp = npvp; *rvp != NULL; rvp++)
816 		{
817 			char **hbrvp;
818 			char **xpvp;
819 			int trsize;
820 			char *olddelimchar;
821 			char *replac;
822 			int endtoken;
823 			STAB *map;
824 			char *mapname;
825 			char **key_rvp;
826 			char **arg_rvp;
827 			char **default_rvp;
828 			char buf[MAXNAME + 1];
829 			char *pvpb1[MAXATOM + 1];
830 			char *argvect[10];
831 			char pvpbuf[PSBUFSIZE];
832 			extern char *DelimChar;
833 
834 			if (**rvp != HOSTBEGIN && **rvp != LOOKUPBEGIN)
835 				continue;
836 
837 			/*
838 			**  Got a hostname/keyword lookup.
839 			**
840 			**	This could be optimized fairly easily.
841 			*/
842 
843 			hbrvp = rvp;
844 			if (**rvp == HOSTBEGIN)
845 			{
846 				endtoken = HOSTEND;
847 				mapname = "host";
848 			}
849 			else
850 			{
851 				endtoken = LOOKUPEND;
852 				mapname = *++rvp;
853 			}
854 			map = stab(mapname, ST_MAP, ST_FIND);
855 			if (map == NULL)
856 				syserr("rewrite: map %s not found", mapname);
857 
858 			/* extract the match part */
859 			key_rvp = ++rvp;
860 			default_rvp = NULL;
861 			arg_rvp = argvect;
862 			xpvp = NULL;
863 			replac = pvpbuf;
864 			while (*rvp != NULL && **rvp != endtoken)
865 			{
866 				int nodetype = **rvp;
867 
868 				if (nodetype != CANONHOST && nodetype != CANONUSER)
869 				{
870 					rvp++;
871 					continue;
872 				}
873 
874 				*rvp++ = NULL;
875 
876 				if (xpvp != NULL)
877 				{
878 					cataddr(xpvp, replac,
879 						&pvpbuf[sizeof pvpbuf] - replac);
880 					*++arg_rvp = replac;
881 					replac += strlen(replac) + 1;
882 					xpvp = NULL;
883 				}
884 				switch (nodetype)
885 				{
886 				  case CANONHOST:
887 					xpvp = rvp;
888 					break;
889 
890 				  case CANONUSER:
891 					default_rvp = rvp;
892 					break;
893 				}
894 			}
895 			if (*rvp != NULL)
896 				*rvp++ = NULL;
897 			if (xpvp != NULL)
898 			{
899 				cataddr(xpvp, replac,
900 					&pvpbuf[sizeof pvpbuf] - replac);
901 				*++arg_rvp = replac;
902 			}
903 			*++arg_rvp = NULL;
904 
905 			/* save the remainder of the input string */
906 			trsize = (int) (avp - rvp + 1) * sizeof *rvp;
907 			bcopy((char *) rvp, (char *) pvpb1, trsize);
908 
909 			/* look it up */
910 			cataddr(key_rvp, buf, sizeof buf);
911 			argvect[0] = buf;
912 			if (map != NULL && bitset(MF_VALID, map->s_map.map_flags))
913 			{
914 				int bsize = sizeof buf - 1;
915 
916 				if (map->s_map.map_app != NULL)
917 					bsize -= strlen(map->s_map.map_app);
918 				replac = (*map->s_map.map_class->map_lookup)(&map->s_map,
919 						buf, sizeof buf - 1, argvect);
920 				if (replac != NULL && map->s_map.map_app != NULL)
921 					strcat(replac, map->s_map.map_app);
922 			}
923 			else
924 				replac = NULL;
925 
926 			/* if no replacement, use default */
927 			if (replac == NULL && default_rvp != NULL)
928 			{
929 				char buf2[sizeof buf];
930 
931 				/* rewrite the default with % translations */
932 				cataddr(default_rvp, buf2, sizeof buf2);
933 				map_rewrite(buf2, sizeof buf2, buf, sizeof buf,
934 					argvect);
935 				replac = buf;
936 			}
937 
938 			if (replac == NULL)
939 			{
940 				xpvp = key_rvp;
941 			}
942 			else
943 			{
944 				/* scan the new replacement */
945 				olddelimchar = DelimChar;
946 				xpvp = prescan(replac, '\0', pvpbuf);
947 				DelimChar = olddelimchar;
948 				if (xpvp == NULL)
949 				{
950 					syserr("rewrite: cannot prescan map value: %s", replac);
951 					return;
952 				}
953 			}
954 
955 			/* append it to the token list */
956 			for (avp = hbrvp; *xpvp != NULL; xpvp++)
957 			{
958 				*avp++ = newstr(*xpvp);
959 				if (avp >= &npvp[MAXATOM])
960 					goto toolong;
961 			}
962 
963 			/* restore the old trailing information */
964 			for (xpvp = pvpb1; (*avp++ = *xpvp++) != NULL; )
965 				if (avp >= &npvp[MAXATOM])
966 					goto toolong;
967 
968 			break;
969 		}
970 
971 		/*
972 		**  Check for subroutine calls.
973 		*/
974 
975 		if (*npvp != NULL && **npvp == CALLSUBR)
976 		{
977 			bcopy((char *) &npvp[2], (char *) pvp,
978 				(int) (avp - npvp - 2) * sizeof *avp);
979 			if (tTd(21, 3))
980 				printf("-----callsubr %s\n", npvp[1]);
981 			rewrite(pvp, atoi(npvp[1]));
982 		}
983 		else
984 		{
985 			bcopy((char *) npvp, (char *) pvp,
986 				(int) (avp - npvp) * sizeof *avp);
987 		}
988 		if (tTd(21, 4))
989 		{
990 			printf("rewritten as:");
991 			printav(pvp);
992 		}
993 	}
994 
995 	if (OpMode == MD_TEST || tTd(21, 2))
996 	{
997 		printf("rewrite: ruleset %2d returns:", ruleset);
998 		printav(pvp);
999 	}
1000 }
1001 /*
1002 **  BUILDADDR -- build address from token vector.
1003 **
1004 **	Parameters:
1005 **		tv -- token vector.
1006 **		a -- pointer to address descriptor to fill.
1007 **			If NULL, one will be allocated.
1008 **
1009 **	Returns:
1010 **		NULL if there was an error.
1011 **		'a' otherwise.
1012 **
1013 **	Side Effects:
1014 **		fills in 'a'
1015 */
1016 
1017 struct errcodes
1018 {
1019 	char	*ec_name;		/* name of error code */
1020 	int	ec_code;		/* numeric code */
1021 } ErrorCodes[] =
1022 {
1023 	"usage",	EX_USAGE,
1024 	"nouser",	EX_NOUSER,
1025 	"nohost",	EX_NOHOST,
1026 	"unavailable",	EX_UNAVAILABLE,
1027 	"software",	EX_SOFTWARE,
1028 	"tempfail",	EX_TEMPFAIL,
1029 	"protocol",	EX_PROTOCOL,
1030 #ifdef EX_CONFIG
1031 	"config",	EX_CONFIG,
1032 #endif
1033 	NULL,		EX_UNAVAILABLE,
1034 };
1035 
1036 ADDRESS *
1037 buildaddr(tv, a)
1038 	register char **tv;
1039 	register ADDRESS *a;
1040 {
1041 	struct mailer **mp;
1042 	register struct mailer *m;
1043 	static char buf[MAXNAME];
1044 
1045 	if (a == NULL)
1046 		a = (ADDRESS *) xalloc(sizeof *a);
1047 	bzero((char *) a, sizeof *a);
1048 
1049 	/* figure out what net/mailer to use */
1050 	if (**tv != CANONNET)
1051 	{
1052 		syserr("buildaddr: no net");
1053 		return (NULL);
1054 	}
1055 	tv++;
1056 	if (!strcasecmp(*tv, "error"))
1057 	{
1058 		if (**++tv == CANONHOST)
1059 		{
1060 			register struct errcodes *ep;
1061 
1062 			if (isdigit(**++tv))
1063 			{
1064 				setstat(atoi(*tv));
1065 			}
1066 			else
1067 			{
1068 				for (ep = ErrorCodes; ep->ec_name != NULL; ep++)
1069 					if (strcasecmp(ep->ec_name, *tv) == 0)
1070 						break;
1071 				setstat(ep->ec_code);
1072 			}
1073 			tv++;
1074 		}
1075 		if (**tv != CANONUSER)
1076 			syserr("buildaddr: error: no user");
1077 		buf[0] = '\0';
1078 		while (*++tv != NULL)
1079 		{
1080 			if (buf[0] != '\0')
1081 				(void) strcat(buf, " ");
1082 			(void) strcat(buf, *tv);
1083 		}
1084 		usrerr(buf);
1085 		return (NULL);
1086 	}
1087 
1088 	for (mp = Mailer; (m = *mp++) != NULL; )
1089 	{
1090 		if (!strcasecmp(m->m_name, *tv))
1091 			break;
1092 	}
1093 	if (m == NULL)
1094 	{
1095 		syserr("buildaddr: unknown mailer %s", *tv);
1096 		return (NULL);
1097 	}
1098 	a->q_mailer = m;
1099 
1100 	/* figure out what host (if any) */
1101 	tv++;
1102 	if (!bitnset(M_LOCAL, m->m_flags))
1103 	{
1104 		if (**tv++ != CANONHOST)
1105 		{
1106 			syserr("buildaddr: no host");
1107 			return (NULL);
1108 		}
1109 		buf[0] = '\0';
1110 		while (*tv != NULL && **tv != CANONUSER)
1111 			(void) strcat(buf, *tv++);
1112 		a->q_host = newstr(buf);
1113 	}
1114 	else
1115 		a->q_host = NULL;
1116 
1117 	/* figure out the user */
1118 	if (*tv == NULL || **tv != CANONUSER)
1119 	{
1120 		syserr("buildaddr: no user");
1121 		return (NULL);
1122 	}
1123 
1124 	if (m == LocalMailer && tv[1] != NULL && strcmp(tv[1], "@") == 0)
1125 	{
1126 		tv++;
1127 		a->q_flags |= QNOTREMOTE;
1128 	}
1129 	tv++;
1130 
1131 	/* do special mapping for local mailer */
1132 	if (m == LocalMailer && *tv != NULL)
1133 	{
1134 		register char *p = *tv;
1135 
1136 		if (*p == '"')
1137 			p++;
1138 		if (*p == '|')
1139 			a->q_mailer = m = ProgMailer;
1140 		else if (*p == '/')
1141 			a->q_mailer = m = FileMailer;
1142 		else if (*p == ':')
1143 		{
1144 			/* may be :include: */
1145 			cataddr(tv, buf, sizeof buf);
1146 			p = buf;
1147 			if (*p == '"')
1148 				p++;
1149 			p[9] = '\0';
1150 			if (strcasecmp(p, ":include:") == 0)
1151 				a->q_mailer = m = InclMailer;
1152 		}
1153 	}
1154 
1155 	/* rewrite according recipient mailer rewriting rules */
1156 	rewrite(tv, 2);
1157 	if (m->m_r_rwset > 0)
1158 		rewrite(tv, m->m_r_rwset);
1159 	rewrite(tv, 4);
1160 
1161 	/* save the result for the command line/RCPT argument */
1162 	cataddr(tv, buf, sizeof buf);
1163 	a->q_user = buf;
1164 
1165 	return (a);
1166 }
1167 /*
1168 **  CATADDR -- concatenate pieces of addresses (putting in <LWSP> subs)
1169 **
1170 **	Parameters:
1171 **		pvp -- parameter vector to rebuild.
1172 **		buf -- buffer to build the string into.
1173 **		sz -- size of buf.
1174 **
1175 **	Returns:
1176 **		none.
1177 **
1178 **	Side Effects:
1179 **		Destroys buf.
1180 */
1181 
1182 cataddr(pvp, buf, sz)
1183 	char **pvp;
1184 	char *buf;
1185 	register int sz;
1186 {
1187 	bool oatomtok = FALSE;
1188 	bool natomtok = FALSE;
1189 	register int i;
1190 	register char *p;
1191 
1192 	if (pvp == NULL)
1193 	{
1194 		(void) strcpy(buf, "");
1195 		return;
1196 	}
1197 	p = buf;
1198 	sz -= 2;
1199 	while (*pvp != NULL && (i = strlen(*pvp)) < sz)
1200 	{
1201 		natomtok = (toktype(**pvp) == ATM);
1202 		if (oatomtok && natomtok)
1203 			*p++ = SpaceSub;
1204 		(void) strcpy(p, *pvp);
1205 		oatomtok = natomtok;
1206 		p += i;
1207 		sz -= i + 1;
1208 		pvp++;
1209 	}
1210 	*p = '\0';
1211 }
1212 /*
1213 **  SAMEADDR -- Determine if two addresses are the same
1214 **
1215 **	This is not just a straight comparison -- if the mailer doesn't
1216 **	care about the host we just ignore it, etc.
1217 **
1218 **	Parameters:
1219 **		a, b -- pointers to the internal forms to compare.
1220 **
1221 **	Returns:
1222 **		TRUE -- they represent the same mailbox.
1223 **		FALSE -- they don't.
1224 **
1225 **	Side Effects:
1226 **		none.
1227 */
1228 
1229 bool
1230 sameaddr(a, b)
1231 	register ADDRESS *a;
1232 	register ADDRESS *b;
1233 {
1234 	/* if they don't have the same mailer, forget it */
1235 	if (a->q_mailer != b->q_mailer)
1236 		return (FALSE);
1237 
1238 	/* if the user isn't the same, we can drop out */
1239 	if (strcmp(a->q_user, b->q_user) != 0)
1240 		return (FALSE);
1241 
1242 	/* if the mailer ignores hosts, we have succeeded! */
1243 	if (bitnset(M_LOCAL, a->q_mailer->m_flags))
1244 		return (TRUE);
1245 
1246 	/* otherwise compare hosts (but be careful for NULL ptrs) */
1247 	if (a->q_host == NULL || b->q_host == NULL)
1248 		return (FALSE);
1249 	if (strcmp(a->q_host, b->q_host) != 0)
1250 		return (FALSE);
1251 
1252 	return (TRUE);
1253 }
1254 /*
1255 **  PRINTADDR -- print address (for debugging)
1256 **
1257 **	Parameters:
1258 **		a -- the address to print
1259 **		follow -- follow the q_next chain.
1260 **
1261 **	Returns:
1262 **		none.
1263 **
1264 **	Side Effects:
1265 **		none.
1266 */
1267 
1268 printaddr(a, follow)
1269 	register ADDRESS *a;
1270 	bool follow;
1271 {
1272 	bool first = TRUE;
1273 
1274 	while (a != NULL)
1275 	{
1276 		first = FALSE;
1277 		printf("%x=", a);
1278 		(void) fflush(stdout);
1279 		printf("%s: mailer %d (%s), host `%s', user `%s', ruser `%s'\n",
1280 		       a->q_paddr, a->q_mailer->m_mno, a->q_mailer->m_name,
1281 		       a->q_host, a->q_user, a->q_ruser? a->q_ruser: "<null>");
1282 		printf("\tnext=%x, flags=%o, alias %x\n", a->q_next, a->q_flags,
1283 		       a->q_alias);
1284 		printf("\thome=\"%s\", fullname=\"%s\"\n", a->q_home,
1285 		       a->q_fullname);
1286 
1287 		if (!follow)
1288 			return;
1289 		a = a->q_next;
1290 	}
1291 	if (first)
1292 		printf("[NULL]\n");
1293 }
1294 
1295 /*
1296 **  REMOTENAME -- return the name relative to the current mailer
1297 **
1298 **	Parameters:
1299 **		name -- the name to translate.
1300 **		m -- the mailer that we want to do rewriting relative
1301 **			to.
1302 **		senderaddress -- if set, uses the sender rewriting rules
1303 **			rather than the recipient rewriting rules.
1304 **		canonical -- if set, strip out any comment information,
1305 **			etc.
1306 **
1307 **	Returns:
1308 **		the text string representing this address relative to
1309 **			the receiving mailer.
1310 **
1311 **	Side Effects:
1312 **		none.
1313 **
1314 **	Warnings:
1315 **		The text string returned is tucked away locally;
1316 **			copy it if you intend to save it.
1317 */
1318 
1319 char *
1320 remotename(name, m, senderaddress, canonical, e)
1321 	char *name;
1322 	struct mailer *m;
1323 	bool senderaddress;
1324 	bool canonical;
1325 	register ENVELOPE *e;
1326 {
1327 	register char **pvp;
1328 	char *fancy;
1329 	extern char *macvalue();
1330 	char *oldg = macvalue('g', e);
1331 	static char buf[MAXNAME];
1332 	char lbuf[MAXNAME];
1333 	char pvpbuf[PSBUFSIZE];
1334 	extern char **prescan();
1335 	extern char *crackaddr();
1336 
1337 	if (tTd(12, 1))
1338 		printf("remotename(%s)\n", name);
1339 
1340 	/* don't do anything if we are tagging it as special */
1341 	if ((senderaddress ? m->m_s_rwset : m->m_r_rwset) < 0)
1342 		return (name);
1343 
1344 	/*
1345 	**  Do a heuristic crack of this name to extract any comment info.
1346 	**	This will leave the name as a comment and a $g macro.
1347 	*/
1348 
1349 	if (canonical)
1350 		fancy = "\001g";
1351 	else
1352 		fancy = crackaddr(name);
1353 
1354 	/*
1355 	**  Turn the name into canonical form.
1356 	**	Normally this will be RFC 822 style, i.e., "user@domain".
1357 	**	If this only resolves to "user", and the "C" flag is
1358 	**	specified in the sending mailer, then the sender's
1359 	**	domain will be appended.
1360 	*/
1361 
1362 	pvp = prescan(name, '\0', pvpbuf);
1363 	if (pvp == NULL)
1364 		return (name);
1365 	rewrite(pvp, 3);
1366 	if (e->e_fromdomain != NULL)
1367 	{
1368 		/* append from domain to this address */
1369 		register char **pxp = pvp;
1370 
1371 		/* see if there is an "@domain" in the current name */
1372 		while (*pxp != NULL && strcmp(*pxp, "@") != 0)
1373 			pxp++;
1374 		if (*pxp == NULL)
1375 		{
1376 			/* no.... append the "@domain" from the sender */
1377 			register char **qxq = e->e_fromdomain;
1378 
1379 			while ((*pxp++ = *qxq++) != NULL)
1380 				continue;
1381 			rewrite(pvp, 3);
1382 		}
1383 	}
1384 
1385 	/*
1386 	**  Do more specific rewriting.
1387 	**	Rewrite using ruleset 1 or 2 depending on whether this is
1388 	**		a sender address or not.
1389 	**	Then run it through any receiving-mailer-specific rulesets.
1390 	*/
1391 
1392 	if (senderaddress)
1393 	{
1394 		rewrite(pvp, 1);
1395 		if (m->m_s_rwset > 0)
1396 			rewrite(pvp, m->m_s_rwset);
1397 	}
1398 	else
1399 	{
1400 		rewrite(pvp, 2);
1401 		if (m->m_r_rwset > 0)
1402 			rewrite(pvp, m->m_r_rwset);
1403 	}
1404 
1405 	/*
1406 	**  Do any final sanitation the address may require.
1407 	**	This will normally be used to turn internal forms
1408 	**	(e.g., user@host.LOCAL) into external form.  This
1409 	**	may be used as a default to the above rules.
1410 	*/
1411 
1412 	rewrite(pvp, 4);
1413 
1414 	/*
1415 	**  Now restore the comment information we had at the beginning.
1416 	*/
1417 
1418 	cataddr(pvp, lbuf, sizeof lbuf);
1419 	define('g', lbuf, e);
1420 	expand(fancy, buf, &buf[sizeof buf - 1], e);
1421 	define('g', oldg, e);
1422 
1423 	if (tTd(12, 1))
1424 		printf("remotename => `%s'\n", buf);
1425 	return (buf);
1426 }
1427 /*
1428 **  MAPLOCALUSER -- run local username through ruleset 5 for final redirection
1429 **
1430 **	Parameters:
1431 **		a -- the address to map (but just the user name part).
1432 **		sendq -- the sendq in which to install any replacement
1433 **			addresses.
1434 **
1435 **	Returns:
1436 **		none.
1437 */
1438 
1439 maplocaluser(a, sendq, e)
1440 	register ADDRESS *a;
1441 	ADDRESS **sendq;
1442 	ENVELOPE *e;
1443 {
1444 	register char **pvp;
1445 	register ADDRESS *a1 = NULL;
1446 	char pvpbuf[PSBUFSIZE];
1447 
1448 	if (tTd(29, 1))
1449 	{
1450 		printf("maplocaluser: ");
1451 		printaddr(a, FALSE);
1452 	}
1453 	pvp = prescan(a->q_user, '\0', pvpbuf);
1454 	if (pvp == NULL)
1455 		return;
1456 
1457 	rewrite(pvp, 5);
1458 	if (pvp[0] == NULL || pvp[0][0] != CANONNET)
1459 		return;
1460 
1461 	/* if non-null, mailer destination specified -- has it changed? */
1462 	a1 = buildaddr(pvp, NULL);
1463 	if (a1 == NULL || sameaddr(a, a1))
1464 		return;
1465 
1466 	/* mark old address as dead; insert new address */
1467 	a->q_flags |= QDONTSEND;
1468 	a1->q_alias = a;
1469 	allocaddr(a1, 1, NULL);
1470 	(void) recipient(a1, sendq, e);
1471 }
1472