xref: /freebsd/contrib/sendmail/src/recipient.c (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1 /*
2  * Copyright (c) 1998-2003, 2006 Proofpoint, Inc. and its suppliers.
3  *	All rights reserved.
4  * Copyright (c) 1983, 1995-1997 Eric P. Allman.  All rights reserved.
5  * Copyright (c) 1988, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * By using this file, you agree to the terms and conditions set
9  * forth in the LICENSE file which can be found at the top level of
10  * the sendmail distribution.
11  *
12  */
13 
14 #include <sendmail.h>
15 
16 SM_RCSID("@(#)$Id: recipient.c,v 8.351 2013-11-22 20:51:56 ca Exp $")
17 
18 static void	includetimeout __P((int));
19 static ADDRESS	*self_reference __P((ADDRESS *));
20 static int	sortexpensive __P((ADDRESS *, ADDRESS *));
21 static int	sortbysignature __P((ADDRESS *, ADDRESS *));
22 static int	sorthost __P((ADDRESS *, ADDRESS *));
23 
24 typedef int	sortfn_t __P((ADDRESS *, ADDRESS *));
25 
26 /*
27 **  SORTHOST -- strcmp()-like func for host portion of an ADDRESS
28 **
29 **	Parameters:
30 **		xx -- first ADDRESS
31 **		yy -- second ADDRESS
32 **
33 **	Returns:
34 **		<0 when xx->q_host is less than yy->q_host
35 **		>0 when xx->q_host is greater than yy->q_host
36 **		0 when equal
37 */
38 
39 static int
40 sorthost(xx, yy)
41 	register ADDRESS *xx;
42 	register ADDRESS *yy;
43 {
44 #if _FFR_HOST_SORT_REVERSE
45 	/* XXX maybe compare hostnames from the end? */
46 	return sm_strrevcasecmp(xx->q_host, yy->q_host);
47 #else
48 	return sm_strcasecmp(xx->q_host, yy->q_host);
49 #endif
50 }
51 
52 /*
53 **  SORTEXPENSIVE -- strcmp()-like func for expensive mailers
54 **
55 **  The mailer has been noted already as "expensive" for 'xx'. This
56 **  will give a result relative to 'yy'. Expensive mailers get rated
57 **  "greater than" non-expensive mailers because during the delivery phase
58 **  it will get queued -- no use it getting in the way of less expensive
59 **  recipients. We avoid an MX RR lookup when both 'xx' and 'yy' are
60 **  expensive since an MX RR lookup happens when extracted from the queue
61 **  later.
62 **
63 **	Parameters:
64 **		xx -- first ADDRESS
65 **		yy -- second ADDRESS
66 **
67 **	Returns:
68 **		<0 when xx->q_host is less than yy->q_host and both are
69 **			expensive
70 **		>0 when xx->q_host is greater than yy->q_host, or when
71 **			'yy' is non-expensive
72 **		0 when equal (by expense and q_host)
73 */
74 
75 static int
76 sortexpensive(xx, yy)
77 	ADDRESS *xx;
78 	ADDRESS *yy;
79 {
80 	if (!bitnset(M_EXPENSIVE, yy->q_mailer->m_flags))
81 		return 1; /* xx should go later */
82 #if _FFR_HOST_SORT_REVERSE
83 	/* XXX maybe compare hostnames from the end? */
84 	return sm_strrevcasecmp(xx->q_host, yy->q_host);
85 #else
86 	return sm_strcasecmp(xx->q_host, yy->q_host);
87 #endif
88 }
89 
90 /*
91 **  SORTBYSIGNATURE -- a strcmp()-like func for q_mailer and q_host in ADDRESS
92 **
93 **	Parameters:
94 **		xx -- first ADDRESS
95 **		yy -- second ADDRESS
96 **
97 **	Returns:
98 **		0 when the "signature"'s are same
99 **		<0 when xx->q_signature is less than yy->q_signature
100 **		>0 when xx->q_signature is greater than yy->q_signature
101 **
102 **	Side Effect:
103 **		May set ADDRESS pointer for q_signature if not already set.
104 */
105 
106 static int
107 sortbysignature(xx, yy)
108 	ADDRESS *xx;
109 	ADDRESS *yy;
110 {
111 	register int ret;
112 
113 	/* Let's avoid redoing the signature over and over again */
114 	if (xx->q_signature == NULL)
115 		xx->q_signature = hostsignature(xx->q_mailer, xx->q_host, xx->q_flags & QSECURE);
116 	if (yy->q_signature == NULL)
117 		yy->q_signature = hostsignature(yy->q_mailer, yy->q_host, yy->q_flags & QSECURE);
118 	ret = strcmp(xx->q_signature, yy->q_signature);
119 
120 	/*
121 	**  If the two signatures are the same then we will return a sort
122 	**  value based on 'q_user'. But note that we have reversed xx and yy
123 	**  on purpose. This additional compare helps reduce the number of
124 	**  sameaddr() calls and loops in recipient() for the case when
125 	**  the rcpt list has been provided already in-order.
126 	*/
127 
128 	if (ret == 0)
129 		return strcmp(yy->q_user, xx->q_user);
130 	else
131 		return ret;
132 }
133 
134 /*
135 **  SENDTOLIST -- Designate a send list.
136 **
137 **	The parameter is a comma-separated list of people to send to.
138 **	This routine arranges to send to all of them.
139 **
140 **	Parameters:
141 **		list -- the send list.
142 **		ctladdr -- the address template for the person to
143 **			send to -- effective uid/gid are important.
144 **			This is typically the alias that caused this
145 **			expansion.
146 **		sendq -- a pointer to the head of a queue to put
147 **			these people into.
148 **		aliaslevel -- the current alias nesting depth -- to
149 **			diagnose loops.
150 **		e -- the envelope in which to add these recipients.
151 **
152 **	Returns:
153 **		The number of addresses actually on the list.
154 */
155 
156 /* q_flags bits inherited from ctladdr */
157 #define QINHERITEDBITS	(QPINGONSUCCESS|QPINGONFAILURE|QPINGONDELAY|QHASNOTIFY)
158 
159 int
160 sendtolist(list, ctladdr, sendq, aliaslevel, e)
161 	char *list;
162 	ADDRESS *ctladdr;
163 	ADDRESS **sendq;
164 	int aliaslevel;
165 	register ENVELOPE *e;
166 {
167 	register char *p;
168 	register ADDRESS *SM_NONVOLATILE al; /* list of addresses to send to */
169 	SM_NONVOLATILE char delimiter;		/* the address delimiter */
170 	SM_NONVOLATILE int naddrs;
171 	SM_NONVOLATILE int i;
172 	char *endp;
173 	char *oldto = e->e_to;
174 	char *SM_NONVOLATILE bufp;
175 	char buf[MAXNAME + 1];
176 
177 	if (list == NULL)
178 	{
179 		syserr("sendtolist: null list");
180 		return 0;
181 	}
182 
183 	if (tTd(25, 1))
184 	{
185 		sm_dprintf("sendto: %s\n   ctladdr=", list);
186 		printaddr(sm_debug_file(), ctladdr, false);
187 	}
188 
189 	/* heuristic to determine old versus new style addresses */
190 	if (ctladdr == NULL &&
191 	    (strchr(list, ',') != NULL || strchr(list, ';') != NULL ||
192 	     strchr(list, '<') != NULL || strchr(list, '(') != NULL))
193 		e->e_flags &= ~EF_OLDSTYLE;
194 	delimiter = ' ';
195 	if (!bitset(EF_OLDSTYLE, e->e_flags) || ctladdr != NULL)
196 		delimiter = ',';
197 
198 	al = NULL;
199 	naddrs = 0;
200 
201 	/* make sure we have enough space to copy the string */
202 	i = strlen(list) + 1;
203 	if (i <= sizeof(buf))
204 	{
205 		bufp = buf;
206 		i = sizeof(buf);
207 	}
208 	else
209 		bufp = sm_malloc_x(i);
210 	endp = bufp + i;
211 
212 	SM_TRY
213 	{
214 		(void) sm_strlcpy(bufp, denlstring(list, false, true), i);
215 
216 		macdefine(&e->e_macro, A_PERM, macid("{addr_type}"), "e r");
217 		for (p = bufp; *p != '\0'; )
218 		{
219 			auto char *delimptr;
220 			register ADDRESS *a;
221 
222 			SM_ASSERT(p < endp);
223 
224 			/* parse the address */
225 			while ((SM_ISSPACE(*p)) || *p == ',')
226 				p++;
227 			SM_ASSERT(p < endp);
228 			a = parseaddr(p, NULLADDR, RF_COPYALL, delimiter,
229 				      &delimptr, e, true);
230 			p = delimptr;
231 			SM_ASSERT(p < endp);
232 			if (a == NULL)
233 				continue;
234 			a->q_next = al;
235 			a->q_alias = ctladdr;
236 
237 			/* arrange to inherit attributes from parent */
238 			if (ctladdr != NULL)
239 			{
240 				ADDRESS *b;
241 
242 				/* self reference test */
243 				if (sameaddr(ctladdr, a))
244 				{
245 					if (tTd(27, 5))
246 					{
247 						sm_dprintf("sendtolist: QSELFREF ");
248 						printaddr(sm_debug_file(), ctladdr, false);
249 					}
250 					ctladdr->q_flags |= QSELFREF;
251 				}
252 
253 				/* check for address loops */
254 				b = self_reference(a);
255 				if (b != NULL)
256 				{
257 					b->q_flags |= QSELFREF;
258 					if (tTd(27, 5))
259 					{
260 						sm_dprintf("sendtolist: QSELFREF ");
261 						printaddr(sm_debug_file(), b, false);
262 					}
263 					if (a != b)
264 					{
265 						if (tTd(27, 5))
266 						{
267 							sm_dprintf("sendtolist: QS_DONTSEND ");
268 							printaddr(sm_debug_file(), a, false);
269 						}
270 						a->q_state = QS_DONTSEND;
271 						b->q_flags |= a->q_flags & QNOTREMOTE;
272 						continue;
273 					}
274 				}
275 
276 				/* full name */
277 				if (a->q_fullname == NULL)
278 					a->q_fullname = ctladdr->q_fullname;
279 
280 				/* various flag bits */
281 				a->q_flags &= ~QINHERITEDBITS;
282 				a->q_flags |= ctladdr->q_flags & QINHERITEDBITS;
283 
284 				/* DSN recipient information */
285 				a->q_finalrcpt = ctladdr->q_finalrcpt;
286 				a->q_orcpt = ctladdr->q_orcpt;
287 			}
288 
289 			al = a;
290 		}
291 
292 		/* arrange to send to everyone on the local send list */
293 		while (al != NULL)
294 		{
295 			register ADDRESS *a = al;
296 
297 			al = a->q_next;
298 			a = recipient(a, sendq, aliaslevel, e);
299 			naddrs++;
300 		}
301 	}
302 	SM_FINALLY
303 	{
304 		e->e_to = oldto;
305 		if (bufp != buf)
306 			sm_free(bufp);
307 		macdefine(&e->e_macro, A_PERM, macid("{addr_type}"), NULL);
308 	}
309 	SM_END_TRY
310 	return naddrs;
311 }
312 
313 #if MILTER
314 /*
315 **  REMOVEFROMLIST -- Remove addresses from a send list.
316 **
317 **	The parameter is a comma-separated list of recipients to remove.
318 **	Note that it only deletes matching addresses.  If those addresses
319 **	have been expanded already in the sendq, it won't mark the
320 **	expanded recipients as QS_REMOVED.
321 **
322 **	Parameters:
323 **		list -- the list to remove.
324 **		sendq -- a pointer to the head of a queue to remove
325 **			these addresses from.
326 **		e -- the envelope in which to remove these recipients.
327 **
328 **	Returns:
329 **		The number of addresses removed from the list.
330 **
331 */
332 
333 int
334 removefromlist(list, sendq, e)
335 	char *list;
336 	ADDRESS **sendq;
337 	ENVELOPE *e;
338 {
339 	SM_NONVOLATILE char delimiter;		/* the address delimiter */
340 	SM_NONVOLATILE int naddrs;
341 	SM_NONVOLATILE int i;
342 	char *p;
343 	char *oldto = e->e_to;
344 	char *SM_NONVOLATILE bufp;
345 	char buf[MAXNAME + 1];
346 
347 	if (list == NULL)
348 	{
349 		syserr("removefromlist: null list");
350 		return 0;
351 	}
352 
353 	if (tTd(25, 1))
354 		sm_dprintf("removefromlist: %s\n", list);
355 
356 	/* heuristic to determine old versus new style addresses */
357 	if (strchr(list, ',') != NULL || strchr(list, ';') != NULL ||
358 	    strchr(list, '<') != NULL || strchr(list, '(') != NULL)
359 		e->e_flags &= ~EF_OLDSTYLE;
360 	delimiter = ' ';
361 	if (!bitset(EF_OLDSTYLE, e->e_flags))
362 		delimiter = ',';
363 
364 	naddrs = 0;
365 
366 	/* make sure we have enough space to copy the string */
367 	i = strlen(list) + 1;
368 	if (i <= sizeof(buf))
369 	{
370 		bufp = buf;
371 		i = sizeof(buf);
372 	}
373 	else
374 		bufp = sm_malloc_x(i);
375 
376 	SM_TRY
377 	{
378 		(void) sm_strlcpy(bufp, denlstring(list, false, true), i);
379 
380 #if _FFR_ADDR_TYPE_MODES
381 		if (AddrTypeModes)
382 			macdefine(&e->e_macro, A_PERM, macid("{addr_type}"),
383 				  "e r d");
384 		else
385 #endif /* _FFR_ADDR_TYPE_MODES */
386 		macdefine(&e->e_macro, A_PERM, macid("{addr_type}"), "e r");
387 		for (p = bufp; *p != '\0'; )
388 		{
389 			ADDRESS a;	/* parsed address to be removed */
390 			ADDRESS *q;
391 			ADDRESS **pq;
392 			char *delimptr;
393 
394 			/* parse the address */
395 			while ((SM_ISSPACE(*p)) || *p == ',')
396 				p++;
397 			if (parseaddr(p, &a, RF_COPYALL|RF_RM_ADDR,
398 				      delimiter, &delimptr, e, true) == NULL)
399 			{
400 				p = delimptr;
401 				continue;
402 			}
403 			p = delimptr;
404 			for (pq = sendq; (q = *pq) != NULL; pq = &q->q_next)
405 			{
406 				if (!QS_IS_DEAD(q->q_state) &&
407 				    (sameaddr(q, &a) ||
408 				     strcmp(q->q_paddr, a.q_paddr) == 0))
409 				{
410 					if (tTd(25, 5))
411 					{
412 						sm_dprintf("removefromlist: QS_REMOVED ");
413 						printaddr(sm_debug_file(), &a, false);
414 					}
415 					q->q_state = QS_REMOVED;
416 					naddrs++;
417 					break;
418 				}
419 			}
420 		}
421 	}
422 	SM_FINALLY
423 	{
424 		e->e_to = oldto;
425 		if (bufp != buf)
426 			sm_free(bufp);
427 		macdefine(&e->e_macro, A_PERM, macid("{addr_type}"), NULL);
428 	}
429 	SM_END_TRY
430 	return naddrs;
431 }
432 #endif /* MILTER */
433 
434 /*
435 **  RECIPIENT -- Designate a message recipient
436 **	Saves the named person for future mailing (after some checks).
437 **
438 **	Parameters:
439 **		new -- the (preparsed) address header for the recipient.
440 **		sendq -- a pointer to the head of a queue to put the
441 **			recipient in.  Duplicate suppression is done
442 **			in this queue.
443 **		aliaslevel -- the current alias nesting depth.
444 **		e -- the current envelope.
445 **
446 **	Returns:
447 **		The actual address in the queue.  This will be "a" if
448 **		the address is not a duplicate, else the original address.
449 **
450 */
451 
452 ADDRESS *
453 recipient(new, sendq, aliaslevel, e)
454 	register ADDRESS *new;
455 	register ADDRESS **sendq;
456 	int aliaslevel;
457 	register ENVELOPE *e;
458 {
459 	register ADDRESS *q;
460 	ADDRESS **pq;
461 	ADDRESS **prev;
462 	register struct mailer *m;
463 	register char *p;
464 	int i, buflen;
465 	bool quoted;		/* set if the addr has a quote bit */
466 	bool insert;
467 	int findusercount;
468 	bool initialdontsend;
469 	char *buf;
470 	char buf0[MAXNAME + 1];		/* unquoted image of the user name */
471 	sortfn_t *sortfn;
472 
473 	p = NULL;
474 	quoted = false;
475 	insert = false;
476 	findusercount = 0;
477 	initialdontsend = QS_IS_DEAD(new->q_state);
478 	e->e_to = new->q_paddr;
479 	m = new->q_mailer;
480 	errno = 0;
481 	if (aliaslevel == 0)
482 		new->q_flags |= QPRIMARY;
483 	if (tTd(26, 1))
484 	{
485 		sm_dprintf("\nrecipient (%d): ", aliaslevel);
486 		printaddr(sm_debug_file(), new, false);
487 	}
488 
489 	/* if this is primary, use it as original recipient */
490 	if (new->q_alias == NULL)
491 	{
492 		if (e->e_origrcpt == NULL)
493 			e->e_origrcpt = new->q_paddr;
494 		else if (e->e_origrcpt != new->q_paddr)
495 			e->e_origrcpt = "";
496 	}
497 
498 	/* find parent recipient for finalrcpt and orcpt */
499 	for (q = new; q->q_alias != NULL; q = q->q_alias)
500 		continue;
501 
502 	/* find final recipient DSN address */
503 	if (new->q_finalrcpt == NULL &&
504 	    e->e_from.q_mailer != NULL)
505 	{
506 		char frbuf[MAXLINE];
507 
508 		p = e->e_from.q_mailer->m_addrtype;
509 		if (p == NULL)
510 			p = "rfc822";
511 #if _FFR_EAI
512 		if (sm_strcasecmp(p, "rfc822") == 0 &&
513 		    !addr_is_ascii(q->q_user))
514 			p = "utf-8";
515 #endif
516 		if (sm_strcasecmp(p, "rfc822") != 0)
517 		{
518 			(void) sm_snprintf(frbuf, sizeof(frbuf), "%s; %.800s",
519 					   q->q_mailer->m_addrtype,
520 					   q->q_user);
521 		}
522 		else if (strchr(q->q_user, '@') != NULL)
523 		{
524 			(void) sm_snprintf(frbuf, sizeof(frbuf), "%s; %.800s",
525 					   p, q->q_user);
526 		}
527 		else if (strchr(q->q_paddr, '@') != NULL)
528 		{
529 			char *qp;
530 			bool b;
531 
532 			qp = q->q_paddr;
533 
534 			/* strip brackets from address */
535 			b = false;
536 			if (*qp == '<')
537 			{
538 				b = qp[strlen(qp) - 1] == '>';
539 				if (b)
540 					qp[strlen(qp) - 1] = '\0';
541 				qp++;
542 			}
543 			(void) sm_snprintf(frbuf, sizeof(frbuf), "%s; %.800s",
544 					   p, qp);
545 
546 			/* undo damage */
547 			if (b)
548 				qp[strlen(qp)] = '>';
549 		}
550 		else
551 		{
552 			(void) sm_snprintf(frbuf, sizeof(frbuf),
553 					   "%s; %.700s@%.100s",
554 					   p, q->q_user, MyHostName);
555 		}
556 		new->q_finalrcpt = sm_rpool_strdup_x(e->e_rpool, frbuf);
557 	}
558 
559 #if _FFR_GEN_ORCPT
560 	/* set ORCPT DSN arg if not already set */
561 	if (new->q_orcpt == NULL)
562 	{
563 		/* check for an existing ORCPT */
564 		if (q->q_orcpt != NULL)
565 			new->q_orcpt = q->q_orcpt;
566 		else
567 		{
568 			/* make our own */
569 			bool b = false;
570 			char *qp;
571 			char obuf[MAXLINE];
572 
573 			if (e->e_from.q_mailer != NULL)
574 				p = e->e_from.q_mailer->m_addrtype;
575 			if (p == NULL)
576 				p = "rfc822";
577 			(void) sm_strlcpyn(obuf, sizeof(obuf), 2, p, ";");
578 
579 			qp = q->q_paddr;
580 
581 			/* FFR: Needs to strip comments from stdin addrs */
582 
583 			/* strip brackets from address */
584 			if (*qp == '<')
585 			{
586 				b = qp[strlen(qp) - 1] == '>';
587 				if (b)
588 					qp[strlen(qp) - 1] = '\0';
589 				qp++;
590 			}
591 
592 			p = xtextify(denlstring(qp, true, false), "=");
593 
594 			if (sm_strlcat(obuf, p, sizeof(obuf)) >= sizeof(obuf))
595 			{
596 				/* if too big, don't use it */
597 				obuf[0] = '\0';
598 			}
599 
600 			/* undo damage */
601 			if (b)
602 				qp[strlen(qp)] = '>';
603 
604 			if (obuf[0] != '\0')
605 				new->q_orcpt =
606 					sm_rpool_strdup_x(e->e_rpool, obuf);
607 		}
608 	}
609 #endif /* _FFR_GEN_ORCPT */
610 
611 	/* break aliasing loops */
612 	if (aliaslevel > MaxAliasRecursion)
613 	{
614 		new->q_state = QS_BADADDR;
615 		new->q_status = "5.4.6";
616 		if (new->q_alias != NULL)
617 		{
618 			new->q_alias->q_state = QS_BADADDR;
619 			new->q_alias->q_status = "5.4.6";
620 		}
621 		if ((SuprErrs || !LogUsrErrs) && LogLevel > 0)
622 		{
623 			sm_syslog(LOG_ERR, e->e_id,
624 				"aliasing/forwarding loop broken: %s (%d aliases deep; %d max)",
625 				FileName != NULL ? FileName : "", aliaslevel,
626 				MaxAliasRecursion);
627 		}
628 		usrerrenh(new->q_status,
629 			  "554 aliasing/forwarding loop broken (%d aliases deep; %d max)",
630 			  aliaslevel, MaxAliasRecursion);
631 		return new;
632 	}
633 
634 	/*
635 	**  Finish setting up address structure.
636 	*/
637 
638 	/* get unquoted user for file, program or user.name check */
639 	i = strlen(new->q_user);
640 	if (i >= sizeof(buf0))
641 	{
642 		buflen = i + 1;
643 		buf = xalloc(buflen);
644 	}
645 	else
646 	{
647 		buf = buf0;
648 		buflen = sizeof(buf0);
649 	}
650 	(void) sm_strlcpy(buf, new->q_user, buflen);
651 	for (p = buf; *p != '\0' && !quoted; p++)
652 	{
653 		if (*p == '\\')
654 			quoted = true;
655 	}
656 	stripquotes(buf);
657 
658 	/* check for direct mailing to restricted mailers */
659 	if (m == ProgMailer)
660 	{
661 		if (new->q_alias == NULL || UseMSP ||
662 		    bitset(EF_UNSAFE, e->e_flags))
663 		{
664 			new->q_state = QS_BADADDR;
665 			new->q_status = "5.7.1";
666 			usrerrenh(new->q_status,
667 				  "550 Cannot mail directly to programs");
668 		}
669 		else if (bitset(QBOGUSSHELL, new->q_alias->q_flags))
670 		{
671 			new->q_state = QS_BADADDR;
672 			new->q_status = "5.7.1";
673 			if (new->q_alias->q_ruser == NULL)
674 				usrerrenh(new->q_status,
675 					  "550 UID %ld is an unknown user: cannot mail to programs",
676 					  (long) new->q_alias->q_uid);
677 			else
678 				usrerrenh(new->q_status,
679 					  "550 User %s@%s doesn't have a valid shell for mailing to programs",
680 					  new->q_alias->q_ruser, MyHostName);
681 		}
682 		else if (bitset(QUNSAFEADDR, new->q_alias->q_flags))
683 		{
684 			new->q_state = QS_BADADDR;
685 			new->q_status = "5.7.1";
686 			new->q_rstatus = "550 Unsafe for mailing to programs";
687 			usrerrenh(new->q_status,
688 				  "550 Address %s is unsafe for mailing to programs",
689 				  new->q_alias->q_paddr);
690 		}
691 	}
692 
693 	/*
694 	**  Look up this person in the recipient list.
695 	**	If they are there already, return, otherwise continue.
696 	**	If the list is empty, just add it.  Notice the cute
697 	**	hack to make from addresses suppress things correctly:
698 	**	the QS_DUPLICATE state will be set in the send list.
699 	**	[Please note: the emphasis is on "hack."]
700 	*/
701 
702 	prev = NULL;
703 
704 	/*
705 	**  If this message is going to the queue or FastSplit is set
706 	**  and it is the first try and the envelope hasn't split, then we
707 	**  avoid doing an MX RR lookup now because one will be done when the
708 	**  message is extracted from the queue later. It can go to the queue
709 	**  because all messages are going to the queue or this mailer of
710 	**  the current recipient is marked expensive.
711 	*/
712 
713 	if (UseMSP || WILL_BE_QUEUED(e->e_sendmode) ||
714 	    (!bitset(EF_SPLIT, e->e_flags) && e->e_ntries == 0 &&
715 	     FastSplit > 0))
716 		sortfn = sorthost;
717 	else if (NoConnect && bitnset(M_EXPENSIVE, new->q_mailer->m_flags))
718 		sortfn = sortexpensive;
719 	else
720 		sortfn = sortbysignature;
721 
722 	for (pq = sendq; (q = *pq) != NULL; pq = &q->q_next)
723 	{
724 		/*
725 		**  If address is "less than" it should be inserted now.
726 		**  If address is "greater than" current comparison it'll
727 		**  insert later in the list; so loop again (if possible).
728 		**  If address is "equal" (different equal than sameaddr()
729 		**  call) then check if sameaddr() will be true.
730 		**  Because this list is now sorted, it'll mean fewer
731 		**  comparisons and fewer loops which is important for more
732 		**  recipients.
733 		*/
734 
735 		i = (*sortfn)(new, q);
736 		if (i == 0) /* equal */
737 		{
738 			/*
739 			**  Sortbysignature() has said that the two have
740 			**  equal MX RR's and the same user. Calling sameaddr()
741 			**  now checks if the two hosts are as identical as the
742 			**  MX RR's are (which might not be the case)
743 			**  before saying these are the identical addresses.
744 			*/
745 
746 			if (sameaddr(q, new) &&
747 			    (bitset(QRCPTOK, q->q_flags) ||
748 			     !bitset(QPRIMARY, q->q_flags)))
749 			{
750 				if (tTd(26, 1))
751 				{
752 					sm_dprintf("%s in sendq: ",
753 						   new->q_paddr);
754 					printaddr(sm_debug_file(), q, false);
755 				}
756 				if (!bitset(QPRIMARY, q->q_flags))
757 				{
758 					if (!QS_IS_DEAD(new->q_state))
759 						message("duplicate suppressed");
760 					else
761 						q->q_state = QS_DUPLICATE;
762 					q->q_flags |= new->q_flags;
763 				}
764 				else if (bitset(QSELFREF, q->q_flags)
765 					 || q->q_state == QS_REMOVED)
766 				{
767 					/*
768 					**  If an earlier milter removed the
769 					**  address, a later one can still add
770 					**  it back.
771 					*/
772 
773 					q->q_state = new->q_state;
774 					q->q_flags |= new->q_flags;
775 				}
776 				new = q;
777 				goto done;
778 			}
779 		}
780 		else if (i < 0) /* less than */
781 		{
782 			insert = true;
783 			break;
784 		}
785 		prev = pq;
786 	}
787 
788 	/* pq should point to an address, never NULL */
789 	SM_ASSERT(pq != NULL);
790 
791 	/* add address on list */
792 	if (insert)
793 	{
794 		/*
795 		**  insert before 'pq'. Only possible when at least 1
796 		**  ADDRESS is in the list already.
797 		*/
798 
799 		new->q_next = *pq;
800 		if (prev == NULL)
801 			*sendq = new; /* To be the first ADDRESS */
802 		else
803 			(*prev)->q_next = new;
804 	}
805 	else
806 	{
807 		/*
808 		**  Place in list at current 'pq' position. Possible
809 		**  when there are 0 or more ADDRESS's in the list.
810 		*/
811 
812 		new->q_next = NULL;
813 		*pq = new;
814 	}
815 
816 	/* added a new address: clear split flag */
817 	e->e_flags &= ~EF_SPLIT;
818 
819 	/*
820 	**  Alias the name and handle special mailer types.
821 	*/
822 
823   trylocaluser:
824 	if (tTd(29, 7))
825 	{
826 		sm_dprintf("at trylocaluser: ");
827 		printaddr(sm_debug_file(), new, false);
828 	}
829 
830 	if (!QS_IS_OK(new->q_state))
831 	{
832 		if (QS_IS_UNDELIVERED(new->q_state))
833 			e->e_nrcpts++;
834 		goto testselfdestruct;
835 	}
836 
837 	if (m == InclMailer)
838 	{
839 		new->q_state = QS_INCLUDED;
840 		if (new->q_alias == NULL || UseMSP ||
841 		    bitset(EF_UNSAFE, e->e_flags))
842 		{
843 			new->q_state = QS_BADADDR;
844 			new->q_status = "5.7.1";
845 			usrerrenh(new->q_status,
846 				  "550 Cannot mail directly to :include:s");
847 		}
848 		else
849 		{
850 			int ret;
851 
852 			message("including file %s", new->q_user);
853 			ret = include(new->q_user, false, new,
854 				      sendq, aliaslevel, e);
855 			if (transienterror(ret))
856 			{
857 				if (LogLevel > 2)
858 					sm_syslog(LOG_ERR, e->e_id,
859 						  "include %s: transient error: %s",
860 						  shortenstring(new->q_user,
861 								MAXSHORTSTR),
862 								sm_errstring(ret));
863 				new->q_state = QS_QUEUEUP;
864 				usrerr("451 4.2.4 Cannot open %s: %s",
865 					shortenstring(new->q_user,
866 						      MAXSHORTSTR),
867 					sm_errstring(ret));
868 			}
869 			else if (ret != 0)
870 			{
871 				new->q_state = QS_BADADDR;
872 				new->q_status = "5.2.4";
873 				usrerrenh(new->q_status,
874 					  "550 Cannot open %s: %s",
875 					  shortenstring(new->q_user,
876 							MAXSHORTSTR),
877 					  sm_errstring(ret));
878 			}
879 		}
880 	}
881 	else if (m == FileMailer)
882 	{
883 		/* check if allowed */
884 		if (new->q_alias == NULL || UseMSP ||
885 		    bitset(EF_UNSAFE, e->e_flags))
886 		{
887 			new->q_state = QS_BADADDR;
888 			new->q_status = "5.7.1";
889 			usrerrenh(new->q_status,
890 				  "550 Cannot mail directly to files");
891 		}
892 		else if (bitset(QBOGUSSHELL, new->q_alias->q_flags))
893 		{
894 			new->q_state = QS_BADADDR;
895 			new->q_status = "5.7.1";
896 			if (new->q_alias->q_ruser == NULL)
897 				usrerrenh(new->q_status,
898 					  "550 UID %ld is an unknown user: cannot mail to files",
899 					  (long) new->q_alias->q_uid);
900 			else
901 				usrerrenh(new->q_status,
902 					  "550 User %s@%s doesn't have a valid shell for mailing to files",
903 					  new->q_alias->q_ruser, MyHostName);
904 		}
905 		else if (bitset(QUNSAFEADDR, new->q_alias->q_flags))
906 		{
907 			new->q_state = QS_BADADDR;
908 			new->q_status = "5.7.1";
909 			new->q_rstatus = "550 Unsafe for mailing to files";
910 			usrerrenh(new->q_status,
911 				  "550 Address %s is unsafe for mailing to files",
912 				  new->q_alias->q_paddr);
913 		}
914 	}
915 
916 	/* try aliasing */
917 	if (!quoted && QS_IS_OK(new->q_state) &&
918 	    bitnset(M_ALIASABLE, m->m_flags))
919 		alias(new, sendq, aliaslevel, e);
920 
921 #if USERDB
922 	/* if not aliased, look it up in the user database */
923 	if (!bitset(QNOTREMOTE, new->q_flags) &&
924 	    QS_IS_SENDABLE(new->q_state) &&
925 	    bitnset(M_CHECKUDB, m->m_flags))
926 	{
927 		if (udbexpand(new, sendq, aliaslevel, e) == EX_TEMPFAIL)
928 		{
929 			new->q_state = QS_QUEUEUP;
930 			if (e->e_message == NULL)
931 				e->e_message = sm_rpool_strdup_x(e->e_rpool,
932 						"Deferred: user database error");
933 			if (new->q_message == NULL)
934 				new->q_message = "Deferred: user database error";
935 			if (LogLevel > 8)
936 				sm_syslog(LOG_INFO, e->e_id,
937 					  "deferred: udbexpand: %s",
938 					  sm_errstring(errno));
939 			message("queued (user database error): %s",
940 				sm_errstring(errno));
941 			e->e_nrcpts++;
942 			goto testselfdestruct;
943 		}
944 	}
945 #endif /* USERDB */
946 
947 	/*
948 	**  If we have a level two config file, then pass the name through
949 	**  Ruleset 5 before sending it off.  Ruleset 5 has the right
950 	**  to rewrite it to another mailer.  This gives us a hook
951 	**  after local aliasing has been done.
952 	*/
953 
954 	if (tTd(29, 5))
955 	{
956 		sm_dprintf("recipient: testing local?  cl=%d, rr5=%p\n\t",
957 			   ConfigLevel, (void *)RewriteRules[5]);
958 		printaddr(sm_debug_file(), new, false);
959 	}
960 	if (ConfigLevel >= 2 && RewriteRules[5] != NULL &&
961 	    bitnset(M_TRYRULESET5, m->m_flags) &&
962 	    !bitset(QNOTREMOTE, new->q_flags) &&
963 	    QS_IS_OK(new->q_state))
964 	{
965 		maplocaluser(new, sendq, aliaslevel + 1, e);
966 	}
967 
968 	/*
969 	**  If it didn't get rewritten to another mailer, go ahead
970 	**  and deliver it.
971 	*/
972 
973 	if (QS_IS_OK(new->q_state) &&
974 	    bitnset(M_HASPWENT, m->m_flags))
975 	{
976 		auto bool fuzzy;
977 		SM_MBDB_T user;
978 		int status;
979 
980 		/* warning -- finduser may trash buf */
981 		status = finduser(buf, &fuzzy, &user);
982 		switch (status)
983 		{
984 		  case EX_TEMPFAIL:
985 			new->q_state = QS_QUEUEUP;
986 			new->q_status = "4.5.2";
987 			giveresponse(EX_TEMPFAIL, new->q_status, m, NULL,
988 				     new->q_alias, (time_t) 0, e, new);
989 			break;
990 		  default:
991 			new->q_state = QS_BADADDR;
992 			new->q_status = "5.1.1";
993 			new->q_rstatus = "550 5.1.1 User unknown";
994 			giveresponse(EX_NOUSER, new->q_status, m, NULL,
995 				     new->q_alias, (time_t) 0, e, new);
996 			break;
997 		  case EX_OK:
998 			if (fuzzy)
999 			{
1000 				/* name was a fuzzy match */
1001 				new->q_user = sm_rpool_strdup_x(e->e_rpool,
1002 								user.mbdb_name);
1003 				if (findusercount++ > 3)
1004 				{
1005 					new->q_state = QS_BADADDR;
1006 					new->q_status = "5.4.6";
1007 					usrerrenh(new->q_status,
1008 						  "554 aliasing/forwarding loop for %s broken",
1009 						  user.mbdb_name);
1010 					goto done;
1011 				}
1012 
1013 				/* see if it aliases */
1014 				(void) sm_strlcpy(buf, user.mbdb_name, buflen);
1015 				goto trylocaluser;
1016 			}
1017 			if (*user.mbdb_homedir == '\0')
1018 				new->q_home = NULL;
1019 			else if (strcmp(user.mbdb_homedir, "/") == 0)
1020 				new->q_home = "";
1021 			else
1022 				new->q_home = sm_rpool_strdup_x(e->e_rpool,
1023 							user.mbdb_homedir);
1024 			if (user.mbdb_uid != SM_NO_UID)
1025 			{
1026 				new->q_uid = user.mbdb_uid;
1027 				new->q_gid = user.mbdb_gid;
1028 				new->q_flags |= QGOODUID;
1029 			}
1030 			new->q_ruser = sm_rpool_strdup_x(e->e_rpool,
1031 							 user.mbdb_name);
1032 			if (user.mbdb_fullname[0] != '\0')
1033 				new->q_fullname = sm_rpool_strdup_x(e->e_rpool,
1034 							user.mbdb_fullname);
1035 			if (!usershellok(user.mbdb_name, user.mbdb_shell))
1036 			{
1037 				new->q_flags |= QBOGUSSHELL;
1038 			}
1039 			if (bitset(EF_VRFYONLY, e->e_flags))
1040 			{
1041 				/* don't do any more now */
1042 				new->q_state = QS_VERIFIED;
1043 			}
1044 			else if (!quoted)
1045 				forward(new, sendq, aliaslevel, e);
1046 		}
1047 	}
1048 	if (!QS_IS_DEAD(new->q_state))
1049 		e->e_nrcpts++;
1050 
1051   testselfdestruct:
1052 	new->q_flags |= QTHISPASS;
1053 	if (tTd(26, 8))
1054 	{
1055 		sm_dprintf("testselfdestruct: ");
1056 		printaddr(sm_debug_file(), new, false);
1057 		if (tTd(26, 10))
1058 		{
1059 			sm_dprintf("SENDQ:\n");
1060 			printaddr(sm_debug_file(), *sendq, true);
1061 			sm_dprintf("----\n");
1062 		}
1063 	}
1064 	if (new->q_alias == NULL && new != &e->e_from &&
1065 	    QS_IS_DEAD(new->q_state))
1066 	{
1067 		for (q = *sendq; q != NULL; q = q->q_next)
1068 		{
1069 			if (!QS_IS_DEAD(q->q_state))
1070 				break;
1071 		}
1072 		if (q == NULL)
1073 		{
1074 			new->q_state = QS_BADADDR;
1075 			new->q_status = "5.4.6";
1076 			usrerrenh(new->q_status,
1077 				  "554 aliasing/forwarding loop broken");
1078 		}
1079 	}
1080 
1081   done:
1082 	new->q_flags |= QTHISPASS;
1083 	if (buf != buf0)
1084 		sm_free(buf); /* XXX leak if above code raises exception */
1085 
1086 	/*
1087 	**  If we are at the top level, check to see if this has
1088 	**  expanded to exactly one address.  If so, it can inherit
1089 	**  the primaryness of the address.
1090 	**
1091 	**  While we're at it, clear the QTHISPASS bits.
1092 	*/
1093 
1094 	if (aliaslevel == 0)
1095 	{
1096 		int nrcpts = 0;
1097 		ADDRESS *only = NULL;
1098 
1099 		for (q = *sendq; q != NULL; q = q->q_next)
1100 		{
1101 			if (bitset(QTHISPASS, q->q_flags) &&
1102 			    QS_IS_SENDABLE(q->q_state))
1103 			{
1104 				nrcpts++;
1105 				only = q;
1106 			}
1107 			q->q_flags &= ~QTHISPASS;
1108 		}
1109 		if (nrcpts == 1)
1110 		{
1111 			/* check to see if this actually got a new owner */
1112 			q = only;
1113 			while ((q = q->q_alias) != NULL)
1114 			{
1115 				if (q->q_owner != NULL)
1116 					break;
1117 			}
1118 			if (q == NULL)
1119 				only->q_flags |= QPRIMARY;
1120 		}
1121 		else if (!initialdontsend && nrcpts > 0)
1122 		{
1123 			/* arrange for return receipt */
1124 			e->e_flags |= EF_SENDRECEIPT;
1125 			new->q_flags |= QEXPANDED;
1126 			if (e->e_xfp != NULL &&
1127 			    bitset(QPINGONSUCCESS, new->q_flags))
1128 				(void) sm_io_fprintf(e->e_xfp, SM_TIME_DEFAULT,
1129 						     "%s... expanded to multiple addresses\n",
1130 						     new->q_paddr);
1131 		}
1132 	}
1133 	new->q_flags |= QRCPTOK;
1134 	(void) sm_snprintf(buf0, sizeof(buf0), "%d", e->e_nrcpts);
1135 	macdefine(&e->e_macro, A_TEMP, macid("{nrcpts}"), buf0);
1136 	return new;
1137 }
1138 
1139 /*
1140 **  FINDUSER -- find the password entry for a user.
1141 **
1142 **	This looks a lot like getpwnam, except that it may want to
1143 **	do some fancier pattern matching in /etc/passwd.
1144 **
1145 **	This routine contains most of the time of many sendmail runs.
1146 **	It deserves to be optimized.
1147 **
1148 **	Parameters:
1149 **		name -- the name to match against.
1150 **		fuzzyp -- an outarg that is set to true if this entry
1151 **			was found using the fuzzy matching algorithm;
1152 **			set to false otherwise.
1153 **		user -- structure to fill in if user is found
1154 **
1155 **	Returns:
1156 **		On success, fill in *user, set *fuzzyp and return EX_OK.
1157 **		If the user was not found, return EX_NOUSER.
1158 **		On error, return EX_TEMPFAIL or EX_OSERR.
1159 **
1160 **	Side Effects:
1161 **		may modify name.
1162 */
1163 
1164 int
1165 finduser(name, fuzzyp, user)
1166 	char *name;
1167 	bool *fuzzyp;
1168 	SM_MBDB_T *user;
1169 {
1170 #if MATCHGECOS
1171 	register struct passwd *pw;
1172 #endif
1173 	register char *p;
1174 	bool tryagain;
1175 	int status;
1176 
1177 	if (tTd(29, 4))
1178 		sm_dprintf("finduser(%s): ", name);
1179 
1180 	*fuzzyp = false;
1181 
1182 #if HESIOD && !HESIOD_ALLOW_NUMERIC_LOGIN
1183 	/* DEC Hesiod getpwnam accepts numeric strings -- short circuit it */
1184 	for (p = name; *p != '\0'; p++)
1185 		if (!isascii(*p) || !isdigit(*p))
1186 			break;
1187 	if (*p == '\0')
1188 	{
1189 		if (tTd(29, 4))
1190 			sm_dprintf("failed (numeric input)\n");
1191 		return EX_NOUSER;
1192 	}
1193 #endif /* HESIOD && !HESIOD_ALLOW_NUMERIC_LOGIN */
1194 
1195 	/* look up this login name using fast path */
1196 	status = sm_mbdb_lookup(name, user);
1197 	if (status != EX_NOUSER)
1198 	{
1199 		if (tTd(29, 4))
1200 			sm_dprintf("%s (non-fuzzy)\n", sm_strexit(status));
1201 		return status;
1202 	}
1203 
1204 	/* try mapping it to lower case */
1205 	tryagain = false;
1206 	for (p = name; *p != '\0'; p++)
1207 	{
1208 		if (isascii(*p) && isupper(*p))
1209 		{
1210 			*p = tolower(*p);
1211 			tryagain = true;
1212 		}
1213 	}
1214 	if (tryagain && (status = sm_mbdb_lookup(name, user)) != EX_NOUSER)
1215 	{
1216 		if (tTd(29, 4))
1217 			sm_dprintf("%s (lower case)\n", sm_strexit(status));
1218 		*fuzzyp = true;
1219 		return status;
1220 	}
1221 
1222 #if MATCHGECOS
1223 	/* see if fuzzy matching allowed */
1224 	if (!MatchGecos)
1225 	{
1226 		if (tTd(29, 4))
1227 			sm_dprintf("not found (fuzzy disabled)\n");
1228 		return EX_NOUSER;
1229 	}
1230 
1231 	/* search for a matching full name instead */
1232 	for (p = name; *p != '\0'; p++)
1233 	{
1234 		if (*p == (SpaceSub & 0177) || *p == '_')
1235 			*p = ' ';
1236 	}
1237 	(void) setpwent();
1238 	while ((pw = getpwent()) != NULL)
1239 	{
1240 		char buf[MAXNAME + 1];
1241 
1242 # if 0
1243 		if (sm_strcasecmp(pw->pw_name, name) == 0)
1244 		{
1245 			if (tTd(29, 4))
1246 				sm_dprintf("found (case wrapped)\n");
1247 			break;
1248 		}
1249 # endif /* 0 */
1250 
1251 		sm_pwfullname(pw->pw_gecos, pw->pw_name, buf, sizeof(buf));
1252 		if (strchr(buf, ' ') != NULL && sm_strcasecmp(buf, name) == 0)
1253 		{
1254 			if (tTd(29, 4))
1255 				sm_dprintf("fuzzy matches %s\n", pw->pw_name);
1256 			message("sending to login name %s", pw->pw_name);
1257 			break;
1258 		}
1259 	}
1260 	if (pw != NULL)
1261 		*fuzzyp = true;
1262 	else if (tTd(29, 4))
1263 		sm_dprintf("no fuzzy match found\n");
1264 # if DEC_OSF_BROKEN_GETPWENT	/* DEC OSF/1 3.2 or earlier */
1265 	endpwent();
1266 # endif
1267 	if (pw == NULL)
1268 		return EX_NOUSER;
1269 	sm_mbdb_frompw(user, pw);
1270 	return EX_OK;
1271 #else /* MATCHGECOS */
1272 	if (tTd(29, 4))
1273 		sm_dprintf("not found (fuzzy disabled)\n");
1274 	return EX_NOUSER;
1275 #endif /* MATCHGECOS */
1276 }
1277 
1278 /*
1279 **  WRITABLE -- predicate returning if the file is writable.
1280 **
1281 **	This routine must duplicate the algorithm in sys/fio.c.
1282 **	Unfortunately, we cannot use the access call since we
1283 **	won't necessarily be the real uid when we try to
1284 **	actually open the file.
1285 **
1286 **	Notice that ANY file with ANY execute bit is automatically
1287 **	not writable.  This is also enforced by mailfile.
1288 **
1289 **	Parameters:
1290 **		filename -- the file name to check.
1291 **		ctladdr -- the controlling address for this file.
1292 **		flags -- SFF_* flags to control the function.
1293 **
1294 **	Returns:
1295 **		true -- if we will be able to write this file.
1296 **		false -- if we cannot write this file.
1297 **
1298 **	Side Effects:
1299 **		none.
1300 */
1301 
1302 bool
1303 writable(filename, ctladdr, flags)
1304 	char *filename;
1305 	ADDRESS *ctladdr;
1306 	long flags;
1307 {
1308 	uid_t euid = 0;
1309 	gid_t egid = 0;
1310 	char *user = NULL;
1311 
1312 	if (tTd(44, 5))
1313 		sm_dprintf("writable(%s, 0x%lx)\n", filename, flags);
1314 
1315 	/*
1316 	**  File does exist -- check that it is writable.
1317 	*/
1318 
1319 	if (geteuid() != 0)
1320 	{
1321 		euid = geteuid();
1322 		egid = getegid();
1323 		user = NULL;
1324 	}
1325 	else if (ctladdr != NULL)
1326 	{
1327 		euid = ctladdr->q_uid;
1328 		egid = ctladdr->q_gid;
1329 		user = ctladdr->q_user;
1330 	}
1331 	else if (bitset(SFF_RUNASREALUID, flags))
1332 	{
1333 		euid = RealUid;
1334 		egid = RealGid;
1335 		user = RealUserName;
1336 	}
1337 	else if (FileMailer != NULL && !bitset(SFF_ROOTOK, flags))
1338 	{
1339 		if (FileMailer->m_uid == NO_UID)
1340 		{
1341 			euid = DefUid;
1342 			user = DefUser;
1343 		}
1344 		else
1345 		{
1346 			euid = FileMailer->m_uid;
1347 			user = NULL;
1348 		}
1349 		if (FileMailer->m_gid == NO_GID)
1350 			egid = DefGid;
1351 		else
1352 			egid = FileMailer->m_gid;
1353 	}
1354 	else
1355 	{
1356 		euid = egid = 0;
1357 		user = NULL;
1358 	}
1359 	if (!bitset(SFF_ROOTOK, flags))
1360 	{
1361 		if (euid == 0)
1362 		{
1363 			euid = DefUid;
1364 			user = DefUser;
1365 		}
1366 		if (egid == 0)
1367 			egid = DefGid;
1368 	}
1369 	if (geteuid() == 0 &&
1370 	    (ctladdr == NULL || !bitset(QGOODUID, ctladdr->q_flags)))
1371 		flags |= SFF_SETUIDOK;
1372 
1373 	if (!bitnset(DBS_FILEDELIVERYTOSYMLINK, DontBlameSendmail))
1374 		flags |= SFF_NOSLINK;
1375 	if (!bitnset(DBS_FILEDELIVERYTOHARDLINK, DontBlameSendmail))
1376 		flags |= SFF_NOHLINK;
1377 
1378 	errno = safefile(filename, euid, egid, user, flags, S_IWRITE, NULL);
1379 	return errno == 0;
1380 }
1381 
1382 /*
1383 **  INCLUDE -- handle :include: specification.
1384 **
1385 **	Parameters:
1386 **		fname -- filename to include.
1387 **		forwarding -- if true, we are reading a .forward file.
1388 **			if false, it's a :include: file.
1389 **		ctladdr -- address template to use to fill in these
1390 **			addresses -- effective user/group id are
1391 **			the important things.
1392 **		sendq -- a pointer to the head of the send queue
1393 **			to put these addresses in.
1394 **		aliaslevel -- the alias nesting depth.
1395 **		e -- the current envelope.
1396 **
1397 **	Returns:
1398 **		open error status
1399 **
1400 **	Side Effects:
1401 **		reads the :include: file and sends to everyone
1402 **		listed in that file.
1403 **
1404 **	Security Note:
1405 **		If you have restricted chown (that is, you can't
1406 **		give a file away), it is reasonable to allow programs
1407 **		and files called from this :include: file to be to be
1408 **		run as the owner of the :include: file.  This is bogus
1409 **		if there is any chance of someone giving away a file.
1410 **		We assume that pre-POSIX systems can give away files.
1411 **
1412 **		There is an additional restriction that if you
1413 **		forward to a :include: file, it will not take on
1414 **		the ownership of the :include: file.  This may not
1415 **		be necessary, but shouldn't hurt.
1416 */
1417 
1418 static jmp_buf	CtxIncludeTimeout;
1419 
1420 int
1421 include(fname, forwarding, ctladdr, sendq, aliaslevel, e)
1422 	char *fname;
1423 	bool forwarding;
1424 	ADDRESS *ctladdr;
1425 	ADDRESS **sendq;
1426 	int aliaslevel;
1427 	ENVELOPE *e;
1428 {
1429 	SM_FILE_T *volatile fp = NULL;
1430 	char *oldto = e->e_to;
1431 	char *oldfilename = FileName;
1432 	int oldlinenumber = LineNumber;
1433 	register SM_EVENT *ev = NULL;
1434 	int nincludes;
1435 	int mode;
1436 	volatile bool maxreached = false;
1437 	register ADDRESS *ca;
1438 	volatile uid_t saveduid;
1439 	volatile gid_t savedgid;
1440 	volatile uid_t uid;
1441 	volatile gid_t gid;
1442 	char *volatile user;
1443 	int rval = 0;
1444 	volatile long sfflags = SFF_REGONLY;
1445 	register char *p;
1446 	bool safechown = false;
1447 	volatile bool safedir = false;
1448 	struct stat st;
1449 	char buf[MAXLINE];
1450 
1451 	if (tTd(27, 2))
1452 		sm_dprintf("include(%s)\n", fname);
1453 	if (tTd(27, 4))
1454 		sm_dprintf("   ruid=%ld euid=%ld\n",
1455 			(long) getuid(), (long) geteuid());
1456 	if (tTd(27, 14))
1457 	{
1458 		sm_dprintf("ctladdr ");
1459 		printaddr(sm_debug_file(), ctladdr, false);
1460 	}
1461 
1462 	if (tTd(27, 9))
1463 		sm_dprintf("include: old uid = %ld/%ld\n",
1464 			   (long) getuid(), (long) geteuid());
1465 
1466 	if (forwarding)
1467 	{
1468 		sfflags |= SFF_MUSTOWN|SFF_ROOTOK;
1469 		if (!bitnset(DBS_GROUPWRITABLEFORWARDFILE, DontBlameSendmail))
1470 			sfflags |= SFF_NOGWFILES;
1471 		if (!bitnset(DBS_WORLDWRITABLEFORWARDFILE, DontBlameSendmail))
1472 			sfflags |= SFF_NOWWFILES;
1473 	}
1474 	else
1475 	{
1476 		if (!bitnset(DBS_GROUPWRITABLEINCLUDEFILE, DontBlameSendmail))
1477 			sfflags |= SFF_NOGWFILES;
1478 		if (!bitnset(DBS_WORLDWRITABLEINCLUDEFILE, DontBlameSendmail))
1479 			sfflags |= SFF_NOWWFILES;
1480 	}
1481 
1482 	/*
1483 	**  If RunAsUser set, won't be able to run programs as user
1484 	**  so mark them as unsafe unless the administrator knows better.
1485 	*/
1486 
1487 	if ((geteuid() != 0 || RunAsUid != 0) &&
1488 	    !bitnset(DBS_NONROOTSAFEADDR, DontBlameSendmail))
1489 	{
1490 		if (tTd(27, 4))
1491 			sm_dprintf("include: not safe (euid=%ld, RunAsUid=%ld)\n",
1492 				   (long) geteuid(), (long) RunAsUid);
1493 		ctladdr->q_flags |= QUNSAFEADDR;
1494 	}
1495 
1496 	ca = getctladdr(ctladdr);
1497 	if (ca == NULL ||
1498 	    (ca->q_uid == DefUid && ca->q_gid == 0))
1499 	{
1500 		uid = DefUid;
1501 		gid = DefGid;
1502 		user = DefUser;
1503 	}
1504 	else
1505 	{
1506 		uid = ca->q_uid;
1507 		gid = ca->q_gid;
1508 		user = ca->q_user;
1509 	}
1510 #if MAILER_SETUID_METHOD != USE_SETUID
1511 	saveduid = geteuid();
1512 	savedgid = getegid();
1513 	if (saveduid == 0)
1514 	{
1515 		if (!DontInitGroups)
1516 		{
1517 			if (initgroups(user, gid) == -1)
1518 			{
1519 				rval = EAGAIN;
1520 				syserr("include: initgroups(%s, %ld) failed",
1521 					user, (long) gid);
1522 				goto resetuid;
1523 			}
1524 		}
1525 		else
1526 		{
1527 			GIDSET_T gidset[1];
1528 
1529 			gidset[0] = gid;
1530 			if (setgroups(1, gidset) == -1)
1531 			{
1532 				rval = EAGAIN;
1533 				syserr("include: setgroups() failed");
1534 				goto resetuid;
1535 			}
1536 		}
1537 
1538 		if (gid != 0 && setgid(gid) < -1)
1539 		{
1540 			rval = EAGAIN;
1541 			syserr("setgid(%ld) failure", (long) gid);
1542 			goto resetuid;
1543 		}
1544 		if (uid != 0)
1545 		{
1546 # if MAILER_SETUID_METHOD == USE_SETEUID
1547 			if (seteuid(uid) < 0)
1548 			{
1549 				rval = EAGAIN;
1550 				syserr("seteuid(%ld) failure (real=%ld, eff=%ld)",
1551 					(long) uid, (long) getuid(), (long) geteuid());
1552 				goto resetuid;
1553 			}
1554 # endif /* MAILER_SETUID_METHOD == USE_SETEUID */
1555 # if MAILER_SETUID_METHOD == USE_SETREUID
1556 			if (setreuid(0, uid) < 0)
1557 			{
1558 				rval = EAGAIN;
1559 				syserr("setreuid(0, %ld) failure (real=%ld, eff=%ld)",
1560 					(long) uid, (long) getuid(), (long) geteuid());
1561 				goto resetuid;
1562 			}
1563 # endif /* MAILER_SETUID_METHOD == USE_SETREUID */
1564 		}
1565 	}
1566 #endif /* MAILER_SETUID_METHOD != USE_SETUID */
1567 
1568 	if (tTd(27, 9))
1569 		sm_dprintf("include: new uid = %ld/%ld\n",
1570 			   (long) getuid(), (long) geteuid());
1571 
1572 	/*
1573 	**  If home directory is remote mounted but server is down,
1574 	**  this can hang or give errors; use a timeout to avoid this
1575 	*/
1576 
1577 	if (setjmp(CtxIncludeTimeout) != 0)
1578 	{
1579 		ctladdr->q_state = QS_QUEUEUP;
1580 		errno = 0;
1581 
1582 		/* return pseudo-error code */
1583 		rval = E_SM_OPENTIMEOUT;
1584 		goto resetuid;
1585 	}
1586 	if (TimeOuts.to_fileopen > 0)
1587 		ev = sm_setevent(TimeOuts.to_fileopen, includetimeout, 0);
1588 	else
1589 		ev = NULL;
1590 
1591 
1592 	/* check for writable parent directory */
1593 	p = strrchr(fname, '/');
1594 	if (p != NULL)
1595 	{
1596 		int ret;
1597 
1598 		*p = '\0';
1599 		ret = safedirpath(fname, uid, gid, user,
1600 				  sfflags|SFF_SAFEDIRPATH, 0, 0);
1601 		if (ret == 0)
1602 		{
1603 			/* in safe directory: relax chown & link rules */
1604 			safedir = true;
1605 			sfflags |= SFF_NOPATHCHECK;
1606 		}
1607 		else
1608 		{
1609 			if (bitnset((forwarding ?
1610 				     DBS_FORWARDFILEINUNSAFEDIRPATH :
1611 				     DBS_INCLUDEFILEINUNSAFEDIRPATH),
1612 				    DontBlameSendmail))
1613 				sfflags |= SFF_NOPATHCHECK;
1614 			else if (bitnset((forwarding ?
1615 					  DBS_FORWARDFILEINGROUPWRITABLEDIRPATH :
1616 					  DBS_INCLUDEFILEINGROUPWRITABLEDIRPATH),
1617 					 DontBlameSendmail) &&
1618 				 ret == E_SM_GWDIR)
1619 			{
1620 				setbitn(DBS_GROUPWRITABLEDIRPATHSAFE,
1621 					DontBlameSendmail);
1622 				ret = safedirpath(fname, uid, gid, user,
1623 						  sfflags|SFF_SAFEDIRPATH,
1624 						  0, 0);
1625 				clrbitn(DBS_GROUPWRITABLEDIRPATHSAFE,
1626 					DontBlameSendmail);
1627 				if (ret == 0)
1628 					sfflags |= SFF_NOPATHCHECK;
1629 				else
1630 					sfflags |= SFF_SAFEDIRPATH;
1631 			}
1632 			else
1633 				sfflags |= SFF_SAFEDIRPATH;
1634 			if (ret > E_PSEUDOBASE &&
1635 			    !bitnset((forwarding ?
1636 				      DBS_FORWARDFILEINUNSAFEDIRPATHSAFE :
1637 				      DBS_INCLUDEFILEINUNSAFEDIRPATHSAFE),
1638 				     DontBlameSendmail))
1639 			{
1640 				if (LogLevel > 11)
1641 					sm_syslog(LOG_INFO, e->e_id,
1642 						  "%s: unsafe directory path, marked unsafe",
1643 						  shortenstring(fname, MAXSHORTSTR));
1644 				ctladdr->q_flags |= QUNSAFEADDR;
1645 			}
1646 		}
1647 		*p = '/';
1648 	}
1649 
1650 	/* allow links only in unwritable directories */
1651 	if (!safedir &&
1652 	    !bitnset((forwarding ?
1653 		      DBS_LINKEDFORWARDFILEINWRITABLEDIR :
1654 		      DBS_LINKEDINCLUDEFILEINWRITABLEDIR),
1655 		     DontBlameSendmail))
1656 		sfflags |= SFF_NOLINK;
1657 
1658 	rval = safefile(fname, uid, gid, user, sfflags, S_IREAD, &st);
1659 	if (rval != 0)
1660 	{
1661 		/* don't use this :include: file */
1662 		if (tTd(27, 4))
1663 			sm_dprintf("include: not safe (uid=%ld): %s\n",
1664 				   (long) uid, sm_errstring(rval));
1665 	}
1666 	else if ((fp = sm_io_open(SmFtStdio, SM_TIME_DEFAULT, fname,
1667 				  SM_IO_RDONLY, NULL)) == NULL)
1668 	{
1669 		rval = errno;
1670 		if (tTd(27, 4))
1671 			sm_dprintf("include: open: %s\n", sm_errstring(rval));
1672 	}
1673 	else if (filechanged(fname, sm_io_getinfo(fp,SM_IO_WHAT_FD, NULL), &st))
1674 	{
1675 		rval = E_SM_FILECHANGE;
1676 		if (tTd(27, 4))
1677 			sm_dprintf("include: file changed after open\n");
1678 	}
1679 	if (ev != NULL)
1680 		sm_clrevent(ev);
1681 
1682 resetuid:
1683 
1684 #if HASSETREUID || USESETEUID
1685 	if (saveduid == 0)
1686 	{
1687 		if (uid != 0)
1688 		{
1689 # if USESETEUID
1690 			if (seteuid(0) < 0)
1691 				syserr("!seteuid(0) failure (real=%ld, eff=%ld)",
1692 				       (long) getuid(), (long) geteuid());
1693 # else /* USESETEUID */
1694 			if (setreuid(-1, 0) < 0)
1695 				syserr("!setreuid(-1, 0) failure (real=%ld, eff=%ld)",
1696 				       (long) getuid(), (long) geteuid());
1697 			if (setreuid(RealUid, 0) < 0)
1698 				syserr("!setreuid(%ld, 0) failure (real=%ld, eff=%ld)",
1699 				       (long) RealUid, (long) getuid(),
1700 				       (long) geteuid());
1701 # endif /* USESETEUID */
1702 		}
1703 		if (setgid(savedgid) < 0)
1704 			syserr("!setgid(%ld) failure (real=%ld eff=%ld)",
1705 			       (long) savedgid, (long) getgid(),
1706 			       (long) getegid());
1707 	}
1708 #endif /* HASSETREUID || USESETEUID */
1709 
1710 	if (tTd(27, 9))
1711 		sm_dprintf("include: reset uid = %ld/%ld\n",
1712 			   (long) getuid(), (long) geteuid());
1713 
1714 	if (rval == E_SM_OPENTIMEOUT)
1715 		usrerr("451 4.4.1 open timeout on %s", fname);
1716 
1717 	if (fp == NULL)
1718 		return rval;
1719 
1720 	if (fstat(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), &st) < 0)
1721 	{
1722 		rval = errno;
1723 		syserr("Cannot fstat %s!", fname);
1724 		(void) sm_io_close(fp, SM_TIME_DEFAULT);
1725 		return rval;
1726 	}
1727 
1728 	/* if path was writable, check to avoid file giveaway tricks */
1729 	safechown = chownsafe(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), safedir);
1730 	if (tTd(27, 6))
1731 		sm_dprintf("include: parent of %s is %s, chown is %ssafe\n",
1732 			   fname, safedir ? "safe" : "dangerous",
1733 			   safechown ? "" : "un");
1734 
1735 	/* if no controlling user or coming from an alias delivery */
1736 	if (safechown &&
1737 	    (ca == NULL ||
1738 	     (ca->q_uid == DefUid && ca->q_gid == 0)))
1739 	{
1740 		ctladdr->q_uid = st.st_uid;
1741 		ctladdr->q_gid = st.st_gid;
1742 		ctladdr->q_flags |= QGOODUID;
1743 	}
1744 	if (ca != NULL && ca->q_uid == st.st_uid)
1745 	{
1746 		/* optimization -- avoid getpwuid if we already have info */
1747 		ctladdr->q_flags |= ca->q_flags & QBOGUSSHELL;
1748 		ctladdr->q_ruser = ca->q_ruser;
1749 	}
1750 	else if (!forwarding)
1751 	{
1752 		register struct passwd *pw;
1753 
1754 		pw = sm_getpwuid(st.st_uid);
1755 		if (pw == NULL)
1756 		{
1757 			ctladdr->q_uid = st.st_uid;
1758 			ctladdr->q_flags |= QBOGUSSHELL;
1759 		}
1760 		else
1761 		{
1762 			char *sh;
1763 
1764 			ctladdr->q_ruser = sm_rpool_strdup_x(e->e_rpool,
1765 							     pw->pw_name);
1766 			if (safechown)
1767 				sh = pw->pw_shell;
1768 			else
1769 				sh = "/SENDMAIL/ANY/SHELL/";
1770 			if (!usershellok(pw->pw_name, sh))
1771 			{
1772 				if (LogLevel > 11)
1773 					sm_syslog(LOG_INFO, e->e_id,
1774 						  "%s: user %s has bad shell %s, marked %s",
1775 						  shortenstring(fname,
1776 								MAXSHORTSTR),
1777 						  pw->pw_name, sh,
1778 						  safechown ? "bogus" : "unsafe");
1779 				if (safechown)
1780 					ctladdr->q_flags |= QBOGUSSHELL;
1781 				else
1782 					ctladdr->q_flags |= QUNSAFEADDR;
1783 			}
1784 		}
1785 	}
1786 
1787 	if (bitset(EF_VRFYONLY, e->e_flags))
1788 	{
1789 		/* don't do any more now */
1790 		ctladdr->q_state = QS_VERIFIED;
1791 		e->e_nrcpts++;
1792 		(void) sm_io_close(fp, SM_TIME_DEFAULT);
1793 		return rval;
1794 	}
1795 
1796 	/*
1797 	**  Check to see if some bad guy can write this file
1798 	**
1799 	**	Group write checking could be more clever, e.g.,
1800 	**	guessing as to which groups are actually safe ("sys"
1801 	**	may be; "user" probably is not).
1802 	*/
1803 
1804 	mode = S_IWOTH;
1805 	if (!bitnset((forwarding ?
1806 		      DBS_GROUPWRITABLEFORWARDFILESAFE :
1807 		      DBS_GROUPWRITABLEINCLUDEFILESAFE),
1808 		     DontBlameSendmail))
1809 		mode |= S_IWGRP;
1810 
1811 	if (bitset(mode, st.st_mode))
1812 	{
1813 		if (tTd(27, 6))
1814 			sm_dprintf("include: %s is %s writable, marked unsafe\n",
1815 				   shortenstring(fname, MAXSHORTSTR),
1816 				   bitset(S_IWOTH, st.st_mode) ? "world"
1817 							       : "group");
1818 		if (LogLevel > 11)
1819 			sm_syslog(LOG_INFO, e->e_id,
1820 				  "%s: %s writable %s file, marked unsafe",
1821 				  shortenstring(fname, MAXSHORTSTR),
1822 				  bitset(S_IWOTH, st.st_mode) ? "world" : "group",
1823 				  forwarding ? "forward" : ":include:");
1824 		ctladdr->q_flags |= QUNSAFEADDR;
1825 	}
1826 
1827 	/* read the file -- each line is a comma-separated list. */
1828 	FileName = fname;
1829 	LineNumber = 0;
1830 	ctladdr->q_flags &= ~QSELFREF;
1831 	nincludes = 0;
1832 	while (sm_io_fgets(fp, SM_TIME_DEFAULT, buf, sizeof(buf)) >= 0 &&
1833 	       !maxreached)
1834 	{
1835 		fixcrlf(buf, true);
1836 		LineNumber++;
1837 		if (buf[0] == '#' || buf[0] == '\0')
1838 			continue;
1839 
1840 		/* <sp>#@# introduces a comment anywhere */
1841 		/* for Japanese character sets */
1842 		for (p = buf; (p = strchr(++p, '#')) != NULL; )
1843 		{
1844 			if (p[1] == '@' && p[2] == '#' &&
1845 			    isascii(p[-1]) && isspace(p[-1]) &&
1846 			    (p[3] == '\0' || (SM_ISSPACE(p[3]))))
1847 			{
1848 				--p;
1849 				while (p > buf && isascii(p[-1]) &&
1850 				       isspace(p[-1]))
1851 					--p;
1852 				p[0] = '\0';
1853 				break;
1854 			}
1855 		}
1856 		if (buf[0] == '\0')
1857 			continue;
1858 
1859 		e->e_to = NULL;
1860 		message("%s to %s",
1861 			forwarding ? "forwarding" : "sending", buf);
1862 		if (forwarding && LogLevel > 10)
1863 			sm_syslog(LOG_INFO, e->e_id,
1864 				  "forward %.200s => %s",
1865 				  oldto, shortenstring(buf, MAXSHORTSTR));
1866 
1867 		nincludes += sendtolist(buf, ctladdr, sendq, aliaslevel + 1, e);
1868 
1869 		if (forwarding &&
1870 		    MaxForwardEntries > 0 &&
1871 		    nincludes >= MaxForwardEntries)
1872 		{
1873 			/* just stop reading and processing further entries */
1874 #if 0
1875 			/* additional: (?) */
1876 			ctladdr->q_state = QS_DONTSEND;
1877 #endif /* 0 */
1878 
1879 			syserr("Attempt to forward to more than %d addresses (in %s)!",
1880 				MaxForwardEntries, fname);
1881 			maxreached = true;
1882 		}
1883 	}
1884 
1885 	if (sm_io_error(fp) && tTd(27, 3))
1886 		sm_dprintf("include: read error: %s\n", sm_errstring(errno));
1887 	if (nincludes > 0 && !bitset(QSELFREF, ctladdr->q_flags))
1888 	{
1889 		if (aliaslevel <= MaxAliasRecursion ||
1890 		    ctladdr->q_state != QS_BADADDR)
1891 		{
1892 			ctladdr->q_state = QS_DONTSEND;
1893 			if (tTd(27, 5))
1894 			{
1895 				sm_dprintf("include: QS_DONTSEND ");
1896 				printaddr(sm_debug_file(), ctladdr, false);
1897 			}
1898 		}
1899 	}
1900 
1901 	(void) sm_io_close(fp, SM_TIME_DEFAULT);
1902 	FileName = oldfilename;
1903 	LineNumber = oldlinenumber;
1904 	e->e_to = oldto;
1905 	return rval;
1906 }
1907 
1908 static void
1909 includetimeout(ignore)
1910 	int ignore;
1911 {
1912 	/*
1913 	**  NOTE: THIS CAN BE CALLED FROM A SIGNAL HANDLER.  DO NOT ADD
1914 	**	ANYTHING TO THIS ROUTINE UNLESS YOU KNOW WHAT YOU ARE
1915 	**	DOING.
1916 	*/
1917 
1918 	errno = ETIMEDOUT;
1919 	longjmp(CtxIncludeTimeout, 1);
1920 }
1921 
1922 /*
1923 **  SENDTOARGV -- send to an argument vector.
1924 **
1925 **	Parameters:
1926 **		argv -- argument vector to send to.
1927 **		e -- the current envelope.
1928 **
1929 **	Returns:
1930 **		none.
1931 **
1932 **	Side Effects:
1933 **		puts all addresses on the argument vector onto the
1934 **			send queue.
1935 */
1936 
1937 void
1938 sendtoargv(argv, e)
1939 	register char **argv;
1940 	register ENVELOPE *e;
1941 {
1942 	register char *p;
1943 
1944 	while ((p = *argv++) != NULL)
1945 		(void) sendtolist(p, NULLADDR, &e->e_sendqueue, 0, e);
1946 }
1947 
1948 /*
1949 **  GETCTLADDR -- get controlling address from an address header.
1950 **
1951 **	If none, get one corresponding to the effective userid.
1952 **
1953 **	Parameters:
1954 **		a -- the address to find the controller of.
1955 **
1956 **	Returns:
1957 **		the controlling address.
1958 */
1959 
1960 ADDRESS *
1961 getctladdr(a)
1962 	register ADDRESS *a;
1963 {
1964 	while (a != NULL && !bitset(QGOODUID, a->q_flags))
1965 		a = a->q_alias;
1966 	return a;
1967 }
1968 
1969 /*
1970 **  SELF_REFERENCE -- check to see if an address references itself
1971 **
1972 **	The check is done through a chain of aliases.  If it is part of
1973 **	a loop, break the loop at the "best" address, that is, the one
1974 **	that exists as a real user.
1975 **
1976 **	This is to handle the case of:
1977 **		awc:		Andrew.Chang
1978 **		Andrew.Chang:	awc@mail.server
1979 **	which is a problem only on mail.server.
1980 **
1981 **	Parameters:
1982 **		a -- the address to check.
1983 **
1984 **	Returns:
1985 **		The address that should be retained.
1986 */
1987 
1988 static ADDRESS *
1989 self_reference(a)
1990 	ADDRESS *a;
1991 {
1992 	ADDRESS *b;		/* top entry in self ref loop */
1993 	ADDRESS *c;		/* entry that point to a real mail box */
1994 
1995 	if (tTd(27, 1))
1996 		sm_dprintf("self_reference(%s)\n", a->q_paddr);
1997 
1998 	for (b = a->q_alias; b != NULL; b = b->q_alias)
1999 	{
2000 		if (sameaddr(a, b))
2001 			break;
2002 	}
2003 
2004 	if (b == NULL)
2005 	{
2006 		if (tTd(27, 1))
2007 			sm_dprintf("\t... no self ref\n");
2008 		return NULL;
2009 	}
2010 
2011 	/*
2012 	**  Pick the first address that resolved to a real mail box
2013 	**  i.e has a mbdb entry.  The returned value will be marked
2014 	**  QSELFREF in recipient(), which in turn will disable alias()
2015 	**  from marking it as QS_IS_DEAD(), which mean it will be used
2016 	**  as a deliverable address.
2017 	**
2018 	**  The 2 key thing to note here are:
2019 	**	1) we are in a recursive call sequence:
2020 	**		alias->sendtolist->recipient->alias
2021 	**	2) normally, when we return back to alias(), the address
2022 	**	   will be marked QS_EXPANDED, since alias() assumes the
2023 	**	   expanded form will be used instead of the current address.
2024 	**	   This behaviour is turned off if the address is marked
2025 	**	   QSELFREF.  We set QSELFREF when we return to recipient().
2026 	*/
2027 
2028 	c = a;
2029 	while (c != NULL)
2030 	{
2031 		if (tTd(27, 10))
2032 			sm_dprintf("  %s", c->q_user);
2033 		if (bitnset(M_HASPWENT, c->q_mailer->m_flags))
2034 		{
2035 			SM_MBDB_T user;
2036 
2037 			if (tTd(27, 2))
2038 				sm_dprintf("\t... getpwnam(%s)... ", c->q_user);
2039 			if (sm_mbdb_lookup(c->q_user, &user) == EX_OK)
2040 			{
2041 				if (tTd(27, 2))
2042 					sm_dprintf("found\n");
2043 
2044 				/* ought to cache results here */
2045 				if (sameaddr(b, c))
2046 					return b;
2047 				else
2048 					return c;
2049 			}
2050 			if (tTd(27, 2))
2051 				sm_dprintf("failed\n");
2052 		}
2053 		else
2054 		{
2055 			/* if local delivery, compare usernames */
2056 			if (bitnset(M_LOCALMAILER, c->q_mailer->m_flags) &&
2057 			    b->q_mailer == c->q_mailer)
2058 			{
2059 				if (tTd(27, 2))
2060 					sm_dprintf("\t... local match (%s)\n",
2061 						c->q_user);
2062 				if (sameaddr(b, c))
2063 					return b;
2064 				else
2065 					return c;
2066 			}
2067 		}
2068 		if (tTd(27, 10))
2069 			sm_dprintf("\n");
2070 		c = c->q_alias;
2071 	}
2072 
2073 	if (tTd(27, 1))
2074 		sm_dprintf("\t... cannot break loop for \"%s\"\n", a->q_paddr);
2075 
2076 	return NULL;
2077 }
2078