1 /*
2  * Copyright (c) 1983 Eric P. Allman
3  * Copyright (c) 1988 Regents of the University of California.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms are permitted
7  * provided that the above copyright notice and this paragraph are
8  * duplicated in all such forms and that any documentation,
9  * advertising materials, and other materials related to such
10  * distribution and use acknowledge that the software was developed
11  * by the University of California, Berkeley.  The name of the
12  * University may not be used to endorse or promote products derived
13  * from this software without specific prior written permission.
14  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
16  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
17  */
18 
19 #ifndef lint
20 static char sccsid[] = "@(#)parseaddr.c	5.9 (Berkeley) 06/30/88";
21 #endif /* not lint */
22 
23 # include "sendmail.h"
24 
25 /*
26 **  PARSEADDR -- Parse an address
27 **
28 **	Parses an address and breaks it up into three parts: a
29 **	net to transmit the message on, the host to transmit it
30 **	to, and a user on that host.  These are loaded into an
31 **	ADDRESS header with the values squirreled away if necessary.
32 **	The "user" part may not be a real user; the process may
33 **	just reoccur on that machine.  For example, on a machine
34 **	with an arpanet connection, the address
35 **		csvax.bill@berkeley
36 **	will break up to a "user" of 'csvax.bill' and a host
37 **	of 'berkeley' -- to be transmitted over the arpanet.
38 **
39 **	Parameters:
40 **		addr -- the address to parse.
41 **		a -- a pointer to the address descriptor buffer.
42 **			If NULL, a header will be created.
43 **		copyf -- determines what shall be copied:
44 **			-1 -- don't copy anything.  The printname
45 **				(q_paddr) is just addr, and the
46 **				user & host are allocated internally
47 **				to parse.
48 **			0 -- copy out the parsed user & host, but
49 **				don't copy the printname.
50 **			+1 -- copy everything.
51 **		delim -- the character to terminate the address, passed
52 **			to prescan.
53 **
54 **	Returns:
55 **		A pointer to the address descriptor header (`a' if
56 **			`a' is non-NULL).
57 **		NULL on error.
58 **
59 **	Side Effects:
60 **		none
61 */
62 
63 /* following delimiters are inherent to the internal algorithms */
64 # define DELIMCHARS	"\001()<>,;\\\"\r\n"	/* word delimiters */
65 
66 ADDRESS *
67 parseaddr(addr, a, copyf, delim)
68 	char *addr;
69 	register ADDRESS *a;
70 	int copyf;
71 	char delim;
72 {
73 	register char **pvp;
74 	register struct mailer *m;
75 	char pvpbuf[PSBUFSIZE];
76 	extern char **prescan();
77 	extern ADDRESS *buildaddr();
78 
79 	/*
80 	**  Initialize and prescan address.
81 	*/
82 
83 	CurEnv->e_to = addr;
84 # ifdef DEBUG
85 	if (tTd(20, 1))
86 		printf("\n--parseaddr(%s)\n", addr);
87 # endif DEBUG
88 
89 	pvp = prescan(addr, delim, pvpbuf);
90 	if (pvp == NULL)
91 		return (NULL);
92 
93 	/*
94 	**  Apply rewriting rules.
95 	**	Ruleset 0 does basic parsing.  It must resolve.
96 	*/
97 
98 	rewrite(pvp, 3);
99 	rewrite(pvp, 0);
100 
101 	/*
102 	**  See if we resolved to a real mailer.
103 	*/
104 
105 	if (pvp[0][0] != CANONNET)
106 	{
107 		setstat(EX_USAGE);
108 		usrerr("cannot resolve name");
109 		return (NULL);
110 	}
111 
112 	/*
113 	**  Build canonical address from pvp.
114 	*/
115 
116 	a = buildaddr(pvp, a);
117 	if (a == NULL)
118 		return (NULL);
119 	m = a->q_mailer;
120 
121 	/*
122 	**  Make local copies of the host & user and then
123 	**  transport them out.
124 	*/
125 
126 	if (copyf > 0)
127 	{
128 		extern char *DelimChar;
129 		char savec = *DelimChar;
130 
131 		*DelimChar = '\0';
132 		a->q_paddr = newstr(addr);
133 		*DelimChar = savec;
134 	}
135 	else
136 		a->q_paddr = addr;
137 
138 	if (a->q_user == NULL)
139 		a->q_user = "";
140 	if (a->q_host == NULL)
141 		a->q_host = "";
142 
143 	if (copyf >= 0)
144 	{
145 		a->q_host = newstr(a->q_host);
146 		if (a->q_user != a->q_paddr)
147 			a->q_user = newstr(a->q_user);
148 	}
149 
150 	/*
151 	**  Convert host name to lower case if requested.
152 	**	User name will be done later.
153 	*/
154 
155 	if (!bitnset(M_HST_UPPER, m->m_flags))
156 		makelower(a->q_host);
157 
158 	/*
159 	**  Compute return value.
160 	*/
161 
162 # ifdef DEBUG
163 	if (tTd(20, 1))
164 	{
165 		printf("parseaddr-->");
166 		printaddr(a, FALSE);
167 	}
168 # endif DEBUG
169 
170 	return (a);
171 }
172 /*
173 **  LOWERADDR -- map UPPER->lower case on addresses as requested.
174 **
175 **	Parameters:
176 **		a -- address to be mapped.
177 **
178 **	Returns:
179 **		none.
180 **
181 **	Side Effects:
182 **		none.
183 */
184 
185 loweraddr(a)
186 	register ADDRESS *a;
187 {
188 	register MAILER *m = a->q_mailer;
189 
190 	if (!bitnset(M_USR_UPPER, m->m_flags))
191 		makelower(a->q_user);
192 }
193 /*
194 **  PRESCAN -- Prescan name and make it canonical
195 **
196 **	Scans a name and turns it into a set of tokens.  This process
197 **	deletes blanks and comments (in parentheses).
198 **
199 **	This routine knows about quoted strings and angle brackets.
200 **
201 **	There are certain subtleties to this routine.  The one that
202 **	comes to mind now is that backslashes on the ends of names
203 **	are silently stripped off; this is intentional.  The problem
204 **	is that some versions of sndmsg (like at LBL) set the kill
205 **	character to something other than @ when reading addresses;
206 **	so people type "csvax.eric\@berkeley" -- which screws up the
207 **	berknet mailer.
208 **
209 **	Parameters:
210 **		addr -- the name to chomp.
211 **		delim -- the delimiter for the address, normally
212 **			'\0' or ','; \0 is accepted in any case.
213 **			If '\t' then we are reading the .cf file.
214 **		pvpbuf -- place to put the saved text -- note that
215 **			the pointers are static.
216 **
217 **	Returns:
218 **		A pointer to a vector of tokens.
219 **		NULL on error.
220 **
221 **	Side Effects:
222 **		sets DelimChar to point to the character matching 'delim'.
223 */
224 
225 /* states and character types */
226 # define OPR		0	/* operator */
227 # define ATM		1	/* atom */
228 # define QST		2	/* in quoted string */
229 # define SPC		3	/* chewing up spaces */
230 # define ONE		4	/* pick up one character */
231 
232 # define NSTATES	5	/* number of states */
233 # define TYPE		017	/* mask to select state type */
234 
235 /* meta bits for table */
236 # define M		020	/* meta character; don't pass through */
237 # define B		040	/* cause a break */
238 # define MB		M|B	/* meta-break */
239 
240 static short StateTab[NSTATES][NSTATES] =
241 {
242    /*	oldst	chtype>	OPR	ATM	QST	SPC	ONE	*/
243 	/*OPR*/		OPR|B,	ATM|B,	QST|B,	SPC|MB,	ONE|B,
244 	/*ATM*/		OPR|B,	ATM,	QST|B,	SPC|MB,	ONE|B,
245 	/*QST*/		QST,	QST,	OPR,	QST,	QST,
246 	/*SPC*/		OPR,	ATM,	QST,	SPC|M,	ONE,
247 	/*ONE*/		OPR,	OPR,	OPR,	OPR,	OPR,
248 };
249 
250 # define NOCHAR		-1	/* signal nothing in lookahead token */
251 
252 char	*DelimChar;		/* set to point to the delimiter */
253 
254 char **
255 prescan(addr, delim, pvpbuf)
256 	char *addr;
257 	char delim;
258 	char pvpbuf[];
259 {
260 	register char *p;
261 	register char *q;
262 	register int c;
263 	char **avp;
264 	bool bslashmode;
265 	int cmntcnt;
266 	int anglecnt;
267 	char *tok;
268 	int state;
269 	int newstate;
270 	static char *av[MAXATOM+1];
271 	extern int errno;
272 
273 	/* make sure error messages don't have garbage on them */
274 	errno = 0;
275 
276 	q = pvpbuf;
277 	bslashmode = FALSE;
278 	cmntcnt = 0;
279 	anglecnt = 0;
280 	avp = av;
281 	state = OPR;
282 	c = NOCHAR;
283 	p = addr;
284 # ifdef DEBUG
285 	if (tTd(22, 45))
286 	{
287 		printf("prescan: ");
288 		xputs(p);
289 		(void) putchar('\n');
290 	}
291 # endif DEBUG
292 
293 	do
294 	{
295 		/* read a token */
296 		tok = q;
297 		for (;;)
298 		{
299 			/* store away any old lookahead character */
300 			if (c != NOCHAR)
301 			{
302 				/* see if there is room */
303 				if (q >= &pvpbuf[PSBUFSIZE - 5])
304 				{
305 					usrerr("Address too long");
306 					DelimChar = p;
307 					return (NULL);
308 				}
309 
310 				/* squirrel it away */
311 				*q++ = c;
312 			}
313 
314 			/* read a new input character */
315 			c = *p++;
316 			if (c == '\0')
317 				break;
318 			c &= ~0200;
319 
320 # ifdef DEBUG
321 			if (tTd(22, 101))
322 				printf("c=%c, s=%d; ", c, state);
323 # endif DEBUG
324 
325 			/* chew up special characters */
326 			*q = '\0';
327 			if (bslashmode)
328 			{
329 				/* kludge \! for naive users */
330 				if (c != '!')
331 					c |= 0200;
332 				bslashmode = FALSE;
333 			}
334 			else if (c == '\\')
335 			{
336 				bslashmode = TRUE;
337 				c = NOCHAR;
338 			}
339 			else if (state == QST)
340 			{
341 				/* do nothing, just avoid next clauses */
342 			}
343 			else if (c == '(')
344 			{
345 				cmntcnt++;
346 				c = NOCHAR;
347 			}
348 			else if (c == ')')
349 			{
350 				if (cmntcnt <= 0)
351 				{
352 					usrerr("Unbalanced ')'");
353 					DelimChar = p;
354 					return (NULL);
355 				}
356 				else
357 					cmntcnt--;
358 			}
359 			else if (cmntcnt > 0)
360 				c = NOCHAR;
361 			else if (c == '<')
362 				anglecnt++;
363 			else if (c == '>')
364 			{
365 				if (anglecnt <= 0)
366 				{
367 					usrerr("Unbalanced '>'");
368 					DelimChar = p;
369 					return (NULL);
370 				}
371 				anglecnt--;
372 			}
373 			else if (delim == ' ' && isspace(c))
374 				c = ' ';
375 
376 			if (c == NOCHAR)
377 				continue;
378 
379 			/* see if this is end of input */
380 			if (c == delim && anglecnt <= 0 && state != QST)
381 				break;
382 
383 			newstate = StateTab[state][toktype(c)];
384 # ifdef DEBUG
385 			if (tTd(22, 101))
386 				printf("ns=%02o\n", newstate);
387 # endif DEBUG
388 			state = newstate & TYPE;
389 			if (bitset(M, newstate))
390 				c = NOCHAR;
391 			if (bitset(B, newstate))
392 				break;
393 		}
394 
395 		/* new token */
396 		if (tok != q)
397 		{
398 			*q++ = '\0';
399 # ifdef DEBUG
400 			if (tTd(22, 36))
401 			{
402 				printf("tok=");
403 				xputs(tok);
404 				(void) putchar('\n');
405 			}
406 # endif DEBUG
407 			if (avp >= &av[MAXATOM])
408 			{
409 				syserr("prescan: too many tokens");
410 				DelimChar = p;
411 				return (NULL);
412 			}
413 			*avp++ = tok;
414 		}
415 	} while (c != '\0' && (c != delim || anglecnt > 0));
416 	*avp = NULL;
417 	DelimChar = --p;
418 	if (cmntcnt > 0)
419 		usrerr("Unbalanced '('");
420 	else if (anglecnt > 0)
421 		usrerr("Unbalanced '<'");
422 	else if (state == QST)
423 		usrerr("Unbalanced '\"'");
424 	else if (av[0] != NULL)
425 		return (av);
426 	return (NULL);
427 }
428 /*
429 **  TOKTYPE -- return token type
430 **
431 **	Parameters:
432 **		c -- the character in question.
433 **
434 **	Returns:
435 **		Its type.
436 **
437 **	Side Effects:
438 **		none.
439 */
440 
441 toktype(c)
442 	register char c;
443 {
444 	static char buf[50];
445 	static bool firstime = TRUE;
446 
447 	if (firstime)
448 	{
449 		firstime = FALSE;
450 		expand("\001o", buf, &buf[sizeof buf - 1], CurEnv);
451 		(void) strcat(buf, DELIMCHARS);
452 	}
453 	if (c == MATCHCLASS || c == MATCHREPL || c == MATCHNCLASS)
454 		return (ONE);
455 	if (c == '"')
456 		return (QST);
457 	if (!isascii(c))
458 		return (ATM);
459 	if (isspace(c) || c == ')')
460 		return (SPC);
461 	if (iscntrl(c) || index(buf, c) != NULL)
462 		return (OPR);
463 	return (ATM);
464 }
465 /*
466 **  REWRITE -- apply rewrite rules to token vector.
467 **
468 **	This routine is an ordered production system.  Each rewrite
469 **	rule has a LHS (called the pattern) and a RHS (called the
470 **	rewrite); 'rwr' points the the current rewrite rule.
471 **
472 **	For each rewrite rule, 'avp' points the address vector we
473 **	are trying to match against, and 'pvp' points to the pattern.
474 **	If pvp points to a special match value (MATCHZANY, MATCHANY,
475 **	MATCHONE, MATCHCLASS, MATCHNCLASS) then the address in avp
476 **	matched is saved away in the match vector (pointed to by 'mvp').
477 **
478 **	When a match between avp & pvp does not match, we try to
479 **	back out.  If we back up over MATCHONE, MATCHCLASS, or MATCHNCLASS
480 **	we must also back out the match in mvp.  If we reach a
481 **	MATCHANY or MATCHZANY we just extend the match and start
482 **	over again.
483 **
484 **	When we finally match, we rewrite the address vector
485 **	and try over again.
486 **
487 **	Parameters:
488 **		pvp -- pointer to token vector.
489 **
490 **	Returns:
491 **		none.
492 **
493 **	Side Effects:
494 **		pvp is modified.
495 */
496 
497 struct match
498 {
499 	char	**first;	/* first token matched */
500 	char	**last;		/* last token matched */
501 };
502 
503 # define MAXMATCH	9	/* max params per rewrite */
504 
505 
506 rewrite(pvp, ruleset)
507 	char **pvp;
508 	int ruleset;
509 {
510 	register char *ap;		/* address pointer */
511 	register char *rp;		/* rewrite pointer */
512 	register char **avp;		/* address vector pointer */
513 	register char **rvp;		/* rewrite vector pointer */
514 	register struct match *mlp;	/* cur ptr into mlist */
515 	register struct rewrite *rwr;	/* pointer to current rewrite rule */
516 	struct match mlist[MAXMATCH];	/* stores match on LHS */
517 	char *npvp[MAXATOM+1];		/* temporary space for rebuild */
518 
519 	if (OpMode == MD_TEST || tTd(21, 2))
520 	{
521 		printf("rewrite: ruleset %2d   input:", ruleset);
522 		printav(pvp);
523 	}
524 	if (pvp == NULL)
525 		return;
526 
527 	/*
528 	**  Run through the list of rewrite rules, applying
529 	**	any that match.
530 	*/
531 
532 	for (rwr = RewriteRules[ruleset]; rwr != NULL; )
533 	{
534 # ifdef DEBUG
535 		if (tTd(21, 12))
536 		{
537 			printf("-----trying rule:");
538 			printav(rwr->r_lhs);
539 		}
540 # endif DEBUG
541 
542 		/* try to match on this rule */
543 		mlp = mlist;
544 		rvp = rwr->r_lhs;
545 		avp = pvp;
546 		while ((ap = *avp) != NULL || *rvp != NULL)
547 		{
548 			rp = *rvp;
549 # ifdef DEBUG
550 			if (tTd(21, 35))
551 			{
552 				printf("ap=");
553 				xputs(ap);
554 				printf(", rp=");
555 				xputs(rp);
556 				printf("\n");
557 			}
558 # endif DEBUG
559 			if (rp == NULL)
560 			{
561 				/* end-of-pattern before end-of-address */
562 				goto backup;
563 			}
564 			if (ap == NULL && *rp != MATCHZANY)
565 			{
566 				/* end-of-input */
567 				break;
568 			}
569 
570 			switch (*rp)
571 			{
572 				register STAB *s;
573 
574 			  case MATCHCLASS:
575 			  case MATCHNCLASS:
576 				/* match any token in (not in) a class */
577 				s = stab(ap, ST_CLASS, ST_FIND);
578 				if (s == NULL || !bitnset(rp[1], s->s_class))
579 				{
580 					if (*rp == MATCHCLASS)
581 						goto backup;
582 				}
583 				else if (*rp == MATCHNCLASS)
584 					goto backup;
585 
586 				/* explicit fall-through */
587 
588 			  case MATCHONE:
589 			  case MATCHANY:
590 				/* match exactly one token */
591 				mlp->first = avp;
592 				mlp->last = avp++;
593 				mlp++;
594 				break;
595 
596 			  case MATCHZANY:
597 				/* match zero or more tokens */
598 				mlp->first = avp;
599 				mlp->last = avp - 1;
600 				mlp++;
601 				break;
602 
603 			  default:
604 				/* must have exact match */
605 				if (strcasecmp(rp, ap))
606 					goto backup;
607 				avp++;
608 				break;
609 			}
610 
611 			/* successful match on this token */
612 			rvp++;
613 			continue;
614 
615 		  backup:
616 			/* match failed -- back up */
617 			while (--rvp >= rwr->r_lhs)
618 			{
619 				rp = *rvp;
620 				if (*rp == MATCHANY || *rp == MATCHZANY)
621 				{
622 					/* extend binding and continue */
623 					avp = ++mlp[-1].last;
624 					avp++;
625 					rvp++;
626 					break;
627 				}
628 				avp--;
629 				if (*rp == MATCHONE || *rp == MATCHCLASS ||
630 				    *rp == MATCHNCLASS)
631 				{
632 					/* back out binding */
633 					mlp--;
634 				}
635 			}
636 
637 			if (rvp < rwr->r_lhs)
638 			{
639 				/* total failure to match */
640 				break;
641 			}
642 		}
643 
644 		/*
645 		**  See if we successfully matched
646 		*/
647 
648 		if (rvp < rwr->r_lhs || *rvp != NULL)
649 		{
650 # ifdef DEBUG
651 			if (tTd(21, 10))
652 				printf("----- rule fails\n");
653 # endif DEBUG
654 			rwr = rwr->r_next;
655 			continue;
656 		}
657 
658 		rvp = rwr->r_rhs;
659 # ifdef DEBUG
660 		if (tTd(21, 12))
661 		{
662 			printf("-----rule matches:");
663 			printav(rvp);
664 		}
665 # endif DEBUG
666 
667 		rp = *rvp;
668 		if (*rp == CANONUSER)
669 		{
670 			rvp++;
671 			rwr = rwr->r_next;
672 		}
673 		else if (*rp == CANONHOST)
674 		{
675 			rvp++;
676 			rwr = NULL;
677 		}
678 		else if (*rp == CANONNET)
679 			rwr = NULL;
680 
681 		/* substitute */
682 		for (avp = npvp; *rvp != NULL; rvp++)
683 		{
684 			register struct match *m;
685 			register char **pp;
686 
687 			rp = *rvp;
688 			if (*rp == MATCHREPL)
689 			{
690 				/* substitute from LHS */
691 				m = &mlist[rp[1] - '1'];
692 				if (m >= mlp)
693 				{
694 					syserr("rewrite: ruleset %d: replacement out of bounds", ruleset);
695 					return;
696 				}
697 # ifdef DEBUG
698 				if (tTd(21, 15))
699 				{
700 					printf("$%c:", rp[1]);
701 					pp = m->first;
702 					while (pp <= m->last)
703 					{
704 						printf(" %x=\"", *pp);
705 						(void) fflush(stdout);
706 						printf("%s\"", *pp++);
707 					}
708 					printf("\n");
709 				}
710 # endif DEBUG
711 				pp = m->first;
712 				while (pp <= m->last)
713 				{
714 					if (avp >= &npvp[MAXATOM])
715 					{
716 						syserr("rewrite: expansion too long");
717 						return;
718 					}
719 					*avp++ = *pp++;
720 				}
721 			}
722 			else
723 			{
724 				/* vanilla replacement */
725 				if (avp >= &npvp[MAXATOM])
726 				{
727 	toolong:
728 					syserr("rewrite: expansion too long");
729 					return;
730 				}
731 				*avp++ = rp;
732 			}
733 		}
734 		*avp++ = NULL;
735 
736 		/*
737 		**  Check for any hostname lookups.
738 		*/
739 
740 		for (rvp = npvp; *rvp != NULL; rvp++)
741 		{
742 			char **hbrvp;
743 			char **xpvp;
744 			int trsize;
745 			char *olddelimchar;
746 			char buf[MAXNAME + 1];
747 			char *pvpb1[MAXATOM + 1];
748 			char pvpbuf[PSBUFSIZE];
749 			extern char *DelimChar;
750 
751 			if (**rvp != HOSTBEGIN)
752 				continue;
753 
754 			/*
755 			**  Got a hostname lookup.
756 			**
757 			**	This could be optimized fairly easily.
758 			*/
759 
760 			hbrvp = rvp;
761 
762 			/* extract the match part */
763 			while (*++rvp != NULL && **rvp != HOSTEND)
764 				continue;
765 			if (*rvp != NULL)
766 				*rvp++ = NULL;
767 
768 			/* save the remainder of the input string */
769 			trsize = (int) (avp - rvp + 1) * sizeof *rvp;
770 			bcopy((char *) rvp, (char *) pvpb1, trsize);
771 
772 			/* look it up */
773 			cataddr(++hbrvp, buf, sizeof buf);
774 			maphostname(buf, sizeof buf);
775 
776 			/* scan the new host name */
777 			olddelimchar = DelimChar;
778 			xpvp = prescan(buf, '\0', pvpbuf);
779 			DelimChar = olddelimchar;
780 			if (xpvp == NULL)
781 			{
782 				syserr("rewrite: cannot prescan canonical hostname: %s", buf);
783 				return;
784 			}
785 
786 			/* append it to the token list */
787 			for (avp = --hbrvp; *xpvp != NULL; xpvp++)
788 			{
789 				*avp++ = newstr(*xpvp);
790 				if (avp >= &npvp[MAXATOM])
791 					goto toolong;
792 			}
793 
794 			/* restore the old trailing information */
795 			for (xpvp = pvpb1; (*avp++ = *xpvp++) != NULL; )
796 				if (avp >= &npvp[MAXATOM])
797 					goto toolong;
798 
799 			break;
800 		}
801 
802 		/*
803 		**  Check for subroutine calls.
804 		*/
805 
806 		if (*npvp != NULL && **npvp == CALLSUBR)
807 		{
808 			bcopy((char *) &npvp[2], (char *) pvp,
809 				(int) (avp - npvp - 2) * sizeof *avp);
810 # ifdef DEBUG
811 			if (tTd(21, 3))
812 				printf("-----callsubr %s\n", npvp[1]);
813 # endif DEBUG
814 			rewrite(pvp, atoi(npvp[1]));
815 		}
816 		else
817 		{
818 			bcopy((char *) npvp, (char *) pvp,
819 				(int) (avp - npvp) * sizeof *avp);
820 		}
821 # ifdef DEBUG
822 		if (tTd(21, 4))
823 		{
824 			printf("rewritten as:");
825 			printav(pvp);
826 		}
827 # endif DEBUG
828 	}
829 
830 	if (OpMode == MD_TEST || tTd(21, 2))
831 	{
832 		printf("rewrite: ruleset %2d returns:", ruleset);
833 		printav(pvp);
834 	}
835 }
836 /*
837 **  BUILDADDR -- build address from token vector.
838 **
839 **	Parameters:
840 **		tv -- token vector.
841 **		a -- pointer to address descriptor to fill.
842 **			If NULL, one will be allocated.
843 **
844 **	Returns:
845 **		NULL if there was an error.
846 **		'a' otherwise.
847 **
848 **	Side Effects:
849 **		fills in 'a'
850 */
851 
852 ADDRESS *
853 buildaddr(tv, a)
854 	register char **tv;
855 	register ADDRESS *a;
856 {
857 	static char buf[MAXNAME];
858 	struct mailer **mp;
859 	register struct mailer *m;
860 
861 	if (a == NULL)
862 		a = (ADDRESS *) xalloc(sizeof *a);
863 	bzero((char *) a, sizeof *a);
864 
865 	/* figure out what net/mailer to use */
866 	if (**tv != CANONNET)
867 	{
868 		syserr("buildaddr: no net");
869 		return (NULL);
870 	}
871 	tv++;
872 	if (!strcasecmp(*tv, "error"))
873 	{
874 		if (**++tv == CANONHOST)
875 		{
876 			setstat(atoi(*++tv));
877 			tv++;
878 		}
879 		if (**tv != CANONUSER)
880 			syserr("buildaddr: error: no user");
881 		buf[0] = '\0';
882 		while (*++tv != NULL)
883 		{
884 			if (buf[0] != '\0')
885 				(void) strcat(buf, " ");
886 			(void) strcat(buf, *tv);
887 		}
888 		usrerr(buf);
889 		return (NULL);
890 	}
891 	for (mp = Mailer; (m = *mp++) != NULL; )
892 	{
893 		if (!strcasecmp(m->m_name, *tv))
894 			break;
895 	}
896 	if (m == NULL)
897 	{
898 		syserr("buildaddr: unknown mailer %s", *tv);
899 		return (NULL);
900 	}
901 	a->q_mailer = m;
902 
903 	/* figure out what host (if any) */
904 	tv++;
905 	if (!bitnset(M_LOCAL, m->m_flags))
906 	{
907 		if (**tv++ != CANONHOST)
908 		{
909 			syserr("buildaddr: no host");
910 			return (NULL);
911 		}
912 		buf[0] = '\0';
913 		while (*tv != NULL && **tv != CANONUSER)
914 			(void) strcat(buf, *tv++);
915 		a->q_host = newstr(buf);
916 	}
917 	else
918 		a->q_host = NULL;
919 
920 	/* figure out the user */
921 	if (**tv != CANONUSER)
922 	{
923 		syserr("buildaddr: no user");
924 		return (NULL);
925 	}
926 
927 	/* rewrite according recipient mailer rewriting rules */
928 	rewrite(++tv, 2);
929 	if (m->m_r_rwset > 0)
930 		rewrite(tv, m->m_r_rwset);
931 	rewrite(tv, 4);
932 
933 	/* save the result for the command line/RCPT argument */
934 	cataddr(tv, buf, sizeof buf);
935 	a->q_user = buf;
936 
937 	return (a);
938 }
939 /*
940 **  CATADDR -- concatenate pieces of addresses (putting in <LWSP> subs)
941 **
942 **	Parameters:
943 **		pvp -- parameter vector to rebuild.
944 **		buf -- buffer to build the string into.
945 **		sz -- size of buf.
946 **
947 **	Returns:
948 **		none.
949 **
950 **	Side Effects:
951 **		Destroys buf.
952 */
953 
954 cataddr(pvp, buf, sz)
955 	char **pvp;
956 	char *buf;
957 	register int sz;
958 {
959 	bool oatomtok = FALSE;
960 	bool natomtok = FALSE;
961 	register int i;
962 	register char *p;
963 
964 	if (pvp == NULL)
965 	{
966 		(void) strcpy(buf, "");
967 		return;
968 	}
969 	p = buf;
970 	sz -= 2;
971 	while (*pvp != NULL && (i = strlen(*pvp)) < sz)
972 	{
973 		natomtok = (toktype(**pvp) == ATM);
974 		if (oatomtok && natomtok)
975 			*p++ = SpaceSub;
976 		(void) strcpy(p, *pvp);
977 		oatomtok = natomtok;
978 		p += i;
979 		sz -= i + 1;
980 		pvp++;
981 	}
982 	*p = '\0';
983 }
984 /*
985 **  SAMEADDR -- Determine if two addresses are the same
986 **
987 **	This is not just a straight comparison -- if the mailer doesn't
988 **	care about the host we just ignore it, etc.
989 **
990 **	Parameters:
991 **		a, b -- pointers to the internal forms to compare.
992 **
993 **	Returns:
994 **		TRUE -- they represent the same mailbox.
995 **		FALSE -- they don't.
996 **
997 **	Side Effects:
998 **		none.
999 */
1000 
1001 bool
1002 sameaddr(a, b)
1003 	register ADDRESS *a;
1004 	register ADDRESS *b;
1005 {
1006 	/* if they don't have the same mailer, forget it */
1007 	if (a->q_mailer != b->q_mailer)
1008 		return (FALSE);
1009 
1010 	/* if the user isn't the same, we can drop out */
1011 	if (strcmp(a->q_user, b->q_user) != 0)
1012 		return (FALSE);
1013 
1014 	/* if the mailer ignores hosts, we have succeeded! */
1015 	if (bitnset(M_LOCAL, a->q_mailer->m_flags))
1016 		return (TRUE);
1017 
1018 	/* otherwise compare hosts (but be careful for NULL ptrs) */
1019 	if (a->q_host == NULL || b->q_host == NULL)
1020 		return (FALSE);
1021 	if (strcmp(a->q_host, b->q_host) != 0)
1022 		return (FALSE);
1023 
1024 	return (TRUE);
1025 }
1026 /*
1027 **  PRINTADDR -- print address (for debugging)
1028 **
1029 **	Parameters:
1030 **		a -- the address to print
1031 **		follow -- follow the q_next chain.
1032 **
1033 **	Returns:
1034 **		none.
1035 **
1036 **	Side Effects:
1037 **		none.
1038 */
1039 
1040 # ifdef DEBUG
1041 
1042 printaddr(a, follow)
1043 	register ADDRESS *a;
1044 	bool follow;
1045 {
1046 	bool first = TRUE;
1047 
1048 	while (a != NULL)
1049 	{
1050 		first = FALSE;
1051 		printf("%x=", a);
1052 		(void) fflush(stdout);
1053 		printf("%s: mailer %d (%s), host `%s', user `%s'\n", a->q_paddr,
1054 		       a->q_mailer->m_mno, a->q_mailer->m_name, a->q_host,
1055 		       a->q_user);
1056 		printf("\tnext=%x, flags=%o, alias %x\n", a->q_next, a->q_flags,
1057 		       a->q_alias);
1058 		printf("\thome=\"%s\", fullname=\"%s\"\n", a->q_home,
1059 		       a->q_fullname);
1060 
1061 		if (!follow)
1062 			return;
1063 		a = a->q_next;
1064 	}
1065 	if (first)
1066 		printf("[NULL]\n");
1067 }
1068 
1069 # endif DEBUG
1070 /*
1071 **  REMOTENAME -- return the name relative to the current mailer
1072 **
1073 **	Parameters:
1074 **		name -- the name to translate.
1075 **		m -- the mailer that we want to do rewriting relative
1076 **			to.
1077 **		senderaddress -- if set, uses the sender rewriting rules
1078 **			rather than the recipient rewriting rules.
1079 **		canonical -- if set, strip out any comment information,
1080 **			etc.
1081 **
1082 **	Returns:
1083 **		the text string representing this address relative to
1084 **			the receiving mailer.
1085 **
1086 **	Side Effects:
1087 **		none.
1088 **
1089 **	Warnings:
1090 **		The text string returned is tucked away locally;
1091 **			copy it if you intend to save it.
1092 */
1093 
1094 char *
1095 remotename(name, m, senderaddress, canonical)
1096 	char *name;
1097 	struct mailer *m;
1098 	bool senderaddress;
1099 	bool canonical;
1100 {
1101 	register char **pvp;
1102 	char *fancy;
1103 	extern char *macvalue();
1104 	char *oldg = macvalue('g', CurEnv);
1105 	static char buf[MAXNAME];
1106 	char lbuf[MAXNAME];
1107 	char pvpbuf[PSBUFSIZE];
1108 	extern char **prescan();
1109 	extern char *crackaddr();
1110 
1111 # ifdef DEBUG
1112 	if (tTd(12, 1))
1113 		printf("remotename(%s)\n", name);
1114 # endif DEBUG
1115 
1116 	/* don't do anything if we are tagging it as special */
1117 	if ((senderaddress ? m->m_s_rwset : m->m_r_rwset) < 0)
1118 		return (name);
1119 
1120 	/*
1121 	**  Do a heuristic crack of this name to extract any comment info.
1122 	**	This will leave the name as a comment and a $g macro.
1123 	*/
1124 
1125 	if (canonical)
1126 		fancy = "\001g";
1127 	else
1128 		fancy = crackaddr(name);
1129 
1130 	/*
1131 	**  Turn the name into canonical form.
1132 	**	Normally this will be RFC 822 style, i.e., "user@domain".
1133 	**	If this only resolves to "user", and the "C" flag is
1134 	**	specified in the sending mailer, then the sender's
1135 	**	domain will be appended.
1136 	*/
1137 
1138 	pvp = prescan(name, '\0', pvpbuf);
1139 	if (pvp == NULL)
1140 		return (name);
1141 	rewrite(pvp, 3);
1142 	if (CurEnv->e_fromdomain != NULL)
1143 	{
1144 		/* append from domain to this address */
1145 		register char **pxp = pvp;
1146 
1147 		/* see if there is an "@domain" in the current name */
1148 		while (*pxp != NULL && strcmp(*pxp, "@") != 0)
1149 			pxp++;
1150 		if (*pxp == NULL)
1151 		{
1152 			/* no.... append the "@domain" from the sender */
1153 			register char **qxq = CurEnv->e_fromdomain;
1154 
1155 			while ((*pxp++ = *qxq++) != NULL)
1156 				continue;
1157 			rewrite(pvp, 3);
1158 		}
1159 	}
1160 
1161 	/*
1162 	**  Do more specific rewriting.
1163 	**	Rewrite using ruleset 1 or 2 depending on whether this is
1164 	**		a sender address or not.
1165 	**	Then run it through any receiving-mailer-specific rulesets.
1166 	*/
1167 
1168 	if (senderaddress)
1169 	{
1170 		rewrite(pvp, 1);
1171 		if (m->m_s_rwset > 0)
1172 			rewrite(pvp, m->m_s_rwset);
1173 	}
1174 	else
1175 	{
1176 		rewrite(pvp, 2);
1177 		if (m->m_r_rwset > 0)
1178 			rewrite(pvp, m->m_r_rwset);
1179 	}
1180 
1181 	/*
1182 	**  Do any final sanitation the address may require.
1183 	**	This will normally be used to turn internal forms
1184 	**	(e.g., user@host.LOCAL) into external form.  This
1185 	**	may be used as a default to the above rules.
1186 	*/
1187 
1188 	rewrite(pvp, 4);
1189 
1190 	/*
1191 	**  Now restore the comment information we had at the beginning.
1192 	*/
1193 
1194 	cataddr(pvp, lbuf, sizeof lbuf);
1195 	define('g', lbuf, CurEnv);
1196 	expand(fancy, buf, &buf[sizeof buf - 1], CurEnv);
1197 	define('g', oldg, CurEnv);
1198 
1199 # ifdef DEBUG
1200 	if (tTd(12, 1))
1201 		printf("remotename => `%s'\n", buf);
1202 # endif DEBUG
1203 	return (buf);
1204 }
1205