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[] = "@(#)recipient.c	6.27 (Berkeley) 03/16/93";
11 #endif /* not lint */
12 
13 # include "sendmail.h"
14 # include <sys/stat.h>
15 # include <fcntl.h>
16 # include <pwd.h>
17 
18 /*
19 **  SENDTOLIST -- Designate a send list.
20 **
21 **	The parameter is a comma-separated list of people to send to.
22 **	This routine arranges to send to all of them.
23 **
24 **	Parameters:
25 **		list -- the send list.
26 **		ctladdr -- the address template for the person to
27 **			send to -- effective uid/gid are important.
28 **			This is typically the alias that caused this
29 **			expansion.
30 **		sendq -- a pointer to the head of a queue to put
31 **			these people into.
32 **		e -- the envelope in which to add these recipients.
33 **
34 **	Returns:
35 **		The number of addresses actually on the list.
36 **
37 **	Side Effects:
38 **		none.
39 */
40 
41 # define MAXRCRSN	10
42 
43 sendtolist(list, ctladdr, sendq, e)
44 	char *list;
45 	ADDRESS *ctladdr;
46 	ADDRESS **sendq;
47 	register ENVELOPE *e;
48 {
49 	register char *p;
50 	register ADDRESS *al;	/* list of addresses to send to */
51 	bool firstone;		/* set on first address sent */
52 	char delimiter;		/* the address delimiter */
53 	int naddrs;
54 
55 	if (tTd(25, 1))
56 	{
57 		printf("sendto: %s\n   ctladdr=", list);
58 		printaddr(ctladdr, FALSE);
59 	}
60 
61 	/* heuristic to determine old versus new style addresses */
62 	if (ctladdr == NULL &&
63 	    (strchr(list, ',') != NULL || strchr(list, ';') != NULL ||
64 	     strchr(list, '<') != NULL || strchr(list, '(') != NULL))
65 		e->e_flags &= ~EF_OLDSTYLE;
66 	delimiter = ' ';
67 	if (!bitset(EF_OLDSTYLE, e->e_flags) || ctladdr != NULL)
68 		delimiter = ',';
69 
70 	firstone = TRUE;
71 	al = NULL;
72 	naddrs = 0;
73 
74 	for (p = list; *p != '\0'; )
75 	{
76 		auto char *delimptr;
77 		register ADDRESS *a;
78 
79 		/* parse the address */
80 		while ((isascii(*p) && isspace(*p)) || *p == ',')
81 			p++;
82 		a = parseaddr(p, (ADDRESS *) NULL, 1, delimiter, &delimptr, e);
83 		p = delimptr;
84 		if (a == NULL)
85 			continue;
86 		a->q_next = al;
87 		a->q_alias = ctladdr;
88 
89 		/* see if this should be marked as a primary address */
90 		if (ctladdr == NULL ||
91 		    (firstone && *p == '\0' && bitset(QPRIMARY, ctladdr->q_flags)))
92 			a->q_flags |= QPRIMARY;
93 
94 		if (ctladdr != NULL && sameaddr(ctladdr, a))
95 			ctladdr->q_flags |= QSELFREF;
96 		al = a;
97 		firstone = FALSE;
98 	}
99 
100 	/* arrange to send to everyone on the local send list */
101 	while (al != NULL)
102 	{
103 		register ADDRESS *a = al;
104 		extern ADDRESS *recipient();
105 
106 		al = a->q_next;
107 		a = recipient(a, sendq, e);
108 
109 		/* arrange to inherit full name */
110 		if (a->q_fullname == NULL && ctladdr != NULL)
111 			a->q_fullname = ctladdr->q_fullname;
112 		naddrs++;
113 	}
114 
115 	e->e_to = NULL;
116 	return (naddrs);
117 }
118 /*
119 **  RECIPIENT -- Designate a message recipient
120 **
121 **	Saves the named person for future mailing.
122 **
123 **	Parameters:
124 **		a -- the (preparsed) address header for the recipient.
125 **		sendq -- a pointer to the head of a queue to put the
126 **			recipient in.  Duplicate supression is done
127 **			in this queue.
128 **		e -- the current envelope.
129 **
130 **	Returns:
131 **		The actual address in the queue.  This will be "a" if
132 **		the address is not a duplicate, else the original address.
133 **
134 **	Side Effects:
135 **		none.
136 */
137 
138 extern ADDRESS *getctladdr();
139 
140 ADDRESS *
141 recipient(a, sendq, e)
142 	register ADDRESS *a;
143 	register ADDRESS **sendq;
144 	register ENVELOPE *e;
145 {
146 	register ADDRESS *q;
147 	ADDRESS **pq;
148 	register struct mailer *m;
149 	register char *p;
150 	bool quoted = FALSE;		/* set if the addr has a quote bit */
151 	int findusercount = 0;
152 	char buf[MAXNAME];		/* unquoted image of the user name */
153 	extern int safefile();
154 
155 	e->e_to = a->q_paddr;
156 	m = a->q_mailer;
157 	errno = 0;
158 	if (tTd(26, 1))
159 	{
160 		printf("\nrecipient: ");
161 		printaddr(a, FALSE);
162 	}
163 
164 	/* break aliasing loops */
165 	if (AliasLevel > MAXRCRSN)
166 	{
167 		usrerr("554 aliasing/forwarding loop broken");
168 		return (a);
169 	}
170 
171 	/*
172 	**  Finish setting up address structure.
173 	*/
174 
175 	/* set the queue timeout */
176 	a->q_timeout = TimeOut;
177 
178 	/* get unquoted user for file, program or user.name check */
179 	(void) strcpy(buf, a->q_user);
180 	for (p = buf; *p != '\0' && !quoted; p++)
181 	{
182 		if (*p == '\\')
183 			quoted = TRUE;
184 	}
185 	stripquotes(buf);
186 
187 	/* check for direct mailing to restricted mailers */
188 	if (a->q_alias == NULL && m == ProgMailer)
189 	{
190 		a->q_flags |= QBADADDR;
191 		usrerr("550 Cannot mail directly to programs", m->m_name);
192 	}
193 
194 	/*
195 	**  Look up this person in the recipient list.
196 	**	If they are there already, return, otherwise continue.
197 	**	If the list is empty, just add it.  Notice the cute
198 	**	hack to make from addresses suppress things correctly:
199 	**	the QDONTSEND bit will be set in the send list.
200 	**	[Please note: the emphasis is on "hack."]
201 	*/
202 
203 	for (pq = sendq; (q = *pq) != NULL; pq = &q->q_next)
204 	{
205 		if (sameaddr(q, a))
206 		{
207 			if (tTd(26, 1))
208 			{
209 				printf("%s in sendq: ", a->q_paddr);
210 				printaddr(q, FALSE);
211 			}
212 			if (!bitset(QPRIMARY, q->q_flags))
213 			{
214 				if (!bitset(QDONTSEND, a->q_flags))
215 					message("duplicate suppressed");
216 				q->q_flags |= a->q_flags;
217 			}
218 			return (q);
219 		}
220 	}
221 
222 	/* add address on list */
223 	*pq = a;
224 	a->q_next = NULL;
225 
226 	/*
227 	**  Alias the name and handle special mailer types.
228 	*/
229 
230   trylocaluser:
231 	if (tTd(29, 7))
232 		printf("at trylocaluser %s\n", a->q_user);
233 
234 	if (bitset(QDONTSEND|QBADADDR|QVERIFIED, a->q_flags))
235 		return (a);
236 
237 	if (m == InclMailer)
238 	{
239 		a->q_flags |= QDONTSEND;
240 		if (a->q_alias == NULL)
241 		{
242 			a->q_flags |= QBADADDR;
243 			usrerr("550 Cannot mail directly to :include:s");
244 		}
245 		else
246 		{
247 			int err;
248 
249 			message("including file %s", a->q_user);
250 			err = include(a->q_user, FALSE, a, sendq, e);
251 			if (transienterror(err))
252 				a->q_flags |= QQUEUEUP|QDONTSEND;
253 		}
254 	}
255 	else if (m == FileMailer)
256 	{
257 		struct stat stb;
258 		extern bool writable();
259 
260 		p = strrchr(buf, '/');
261 		/* check if writable or creatable */
262 		if (a->q_alias == NULL && !QueueRun)
263 		{
264 			a->q_flags |= QBADADDR;
265 			usrerr("550 Cannot mail directly to files");
266 		}
267 		else if ((stat(buf, &stb) >= 0) ? (!writable(&stb)) :
268 		    (*p = '\0', safefile(buf, getruid(), S_IWRITE|S_IEXEC) != 0))
269 		{
270 			a->q_flags |= QBADADDR;
271 			giveresponse(EX_CANTCREAT, m, NULL, e);
272 		}
273 	}
274 
275 	if (m != LocalMailer)
276 	{
277 		if (!bitset(QDONTSEND, a->q_flags))
278 			e->e_nrcpts++;
279 		return (a);
280 	}
281 
282 	/* try aliasing */
283 	alias(a, sendq, e);
284 
285 # ifdef USERDB
286 	/* if not aliased, look it up in the user database */
287 	if (!bitset(QDONTSEND|QNOTREMOTE, a->q_flags))
288 	{
289 		extern int udbexpand();
290 
291 		if (udbexpand(a, sendq, e) == EX_TEMPFAIL)
292 		{
293 			a->q_flags |= QQUEUEUP|QDONTSEND;
294 			if (e->e_message == NULL)
295 				e->e_message = newstr("Deferred: user database error");
296 # ifdef LOG
297 			if (LogLevel > 8)
298 				syslog(LOG_INFO, "%s: deferred: udbexpand",
299 					e->e_id);
300 # endif
301 			message("queued (user database error)");
302 			e->e_nrcpts++;
303 			return (a);
304 		}
305 	}
306 # endif
307 
308 	/* if it was an alias or a UDB expansion, just return now */
309 	if (bitset(QDONTSEND|QQUEUEUP|QVERIFIED, a->q_flags))
310 		return (a);
311 
312 	/*
313 	**  If we have a level two config file, then pass the name through
314 	**  Ruleset 5 before sending it off.  Ruleset 5 has the right
315 	**  to send rewrite it to another mailer.  This gives us a hook
316 	**  after local aliasing has been done.
317 	*/
318 
319 	if (tTd(29, 5))
320 	{
321 		printf("recipient: testing local?  cl=%d, rr5=%x\n\t",
322 			ConfigLevel, RewriteRules[5]);
323 		printaddr(a, FALSE);
324 	}
325 	if (!bitset(QNOTREMOTE, a->q_flags) && ConfigLevel >= 2 &&
326 	    RewriteRules[5] != NULL)
327 	{
328 		maplocaluser(a, sendq, e);
329 	}
330 
331 	/*
332 	**  If it didn't get rewritten to another mailer, go ahead
333 	**  and deliver it.
334 	*/
335 
336 	if (!bitset(QDONTSEND|QQUEUEUP, a->q_flags))
337 	{
338 		auto bool fuzzy;
339 		register struct passwd *pw;
340 		extern struct passwd *finduser();
341 
342 		/* warning -- finduser may trash buf */
343 		pw = finduser(buf, &fuzzy);
344 		if (pw == NULL)
345 		{
346 			a->q_flags |= QBADADDR;
347 			giveresponse(EX_NOUSER, m, NULL, e);
348 		}
349 		else
350 		{
351 			char nbuf[MAXNAME];
352 
353 			if (fuzzy)
354 			{
355 				/* name was a fuzzy match */
356 				a->q_user = newstr(pw->pw_name);
357 				if (findusercount++ > 3)
358 				{
359 					a->q_flags |= QBADADDR;
360 					usrerr("554 aliasing/forwarding loop for %s broken",
361 						pw->pw_name);
362 					return (a);
363 				}
364 
365 				/* see if it aliases */
366 				(void) strcpy(buf, pw->pw_name);
367 				goto trylocaluser;
368 			}
369 			a->q_home = newstr(pw->pw_dir);
370 			a->q_uid = pw->pw_uid;
371 			a->q_gid = pw->pw_gid;
372 			a->q_flags |= QGOODUID;
373 			buildfname(pw->pw_gecos, pw->pw_name, nbuf);
374 			if (nbuf[0] != '\0')
375 				a->q_fullname = newstr(nbuf);
376 			if (!quoted)
377 				forward(a, sendq, e);
378 		}
379 	}
380 	if (!bitset(QDONTSEND, a->q_flags))
381 		e->e_nrcpts++;
382 	return (a);
383 }
384 /*
385 **  FINDUSER -- find the password entry for a user.
386 **
387 **	This looks a lot like getpwnam, except that it may want to
388 **	do some fancier pattern matching in /etc/passwd.
389 **
390 **	This routine contains most of the time of many sendmail runs.
391 **	It deserves to be optimized.
392 **
393 **	Parameters:
394 **		name -- the name to match against.
395 **		fuzzyp -- an outarg that is set to TRUE if this entry
396 **			was found using the fuzzy matching algorithm;
397 **			set to FALSE otherwise.
398 **
399 **	Returns:
400 **		A pointer to a pw struct.
401 **		NULL if name is unknown or ambiguous.
402 **
403 **	Side Effects:
404 **		may modify name.
405 */
406 
407 struct passwd *
408 finduser(name, fuzzyp)
409 	char *name;
410 	bool *fuzzyp;
411 {
412 	register struct passwd *pw;
413 	register char *p;
414 	extern struct passwd *getpwent();
415 	extern struct passwd *getpwnam();
416 
417 	if (tTd(29, 4))
418 		printf("finduser(%s): ", name);
419 
420 	/* map upper => lower case */
421 	for (p = name; *p != '\0'; p++)
422 	{
423 		if (isascii(*p) && isupper(*p))
424 			*p = tolower(*p);
425 	}
426 	*fuzzyp = FALSE;
427 
428 	/* look up this login name using fast path */
429 	if ((pw = getpwnam(name)) != NULL)
430 	{
431 		if (tTd(29, 4))
432 			printf("found (non-fuzzy)\n");
433 		return (pw);
434 	}
435 
436 #ifdef MATCHGECOS
437 	/* see if fuzzy matching allowed */
438 	if (!MatchGecos)
439 	{
440 		if (tTd(29, 4))
441 			printf("not found (fuzzy disabled)\n");
442 		return NULL;
443 	}
444 
445 	/* search for a matching full name instead */
446 	for (p = name; *p != '\0'; p++)
447 	{
448 		if (*p == (SpaceSub & 0177) || *p == '_')
449 			*p = ' ';
450 	}
451 	(void) setpwent();
452 	while ((pw = getpwent()) != NULL)
453 	{
454 		char buf[MAXNAME];
455 
456 		buildfname(pw->pw_gecos, pw->pw_name, buf);
457 		if (strchr(buf, ' ') != NULL && !strcasecmp(buf, name))
458 		{
459 			if (tTd(29, 4))
460 				printf("fuzzy matches %s\n", pw->pw_name);
461 			message("sending to login name %s", pw->pw_name);
462 			*fuzzyp = TRUE;
463 			return (pw);
464 		}
465 	}
466 #endif
467 	if (tTd(29, 4))
468 		printf("no fuzzy match found\n");
469 	return (NULL);
470 }
471 /*
472 **  WRITABLE -- predicate returning if the file is writable.
473 **
474 **	This routine must duplicate the algorithm in sys/fio.c.
475 **	Unfortunately, we cannot use the access call since we
476 **	won't necessarily be the real uid when we try to
477 **	actually open the file.
478 **
479 **	Notice that ANY file with ANY execute bit is automatically
480 **	not writable.  This is also enforced by mailfile.
481 **
482 **	Parameters:
483 **		s -- pointer to a stat struct for the file.
484 **
485 **	Returns:
486 **		TRUE -- if we will be able to write this file.
487 **		FALSE -- if we cannot write this file.
488 **
489 **	Side Effects:
490 **		none.
491 */
492 
493 bool
494 writable(s)
495 	register struct stat *s;
496 {
497 	uid_t euid;
498 	gid_t egid;
499 	int bits;
500 
501 	if (bitset(0111, s->st_mode))
502 		return (FALSE);
503 	euid = getruid();
504 	egid = getrgid();
505 	if (geteuid() == 0)
506 	{
507 		if (bitset(S_ISUID, s->st_mode))
508 			euid = s->st_uid;
509 		if (bitset(S_ISGID, s->st_mode))
510 			egid = s->st_gid;
511 	}
512 
513 	if (euid == 0)
514 		return (TRUE);
515 	bits = S_IWRITE;
516 	if (euid != s->st_uid)
517 	{
518 		bits >>= 3;
519 		if (egid != s->st_gid)
520 			bits >>= 3;
521 	}
522 	return ((s->st_mode & bits) != 0);
523 }
524 /*
525 **  INCLUDE -- handle :include: specification.
526 **
527 **	Parameters:
528 **		fname -- filename to include.
529 **		forwarding -- if TRUE, we are reading a .forward file.
530 **			if FALSE, it's a :include: file.
531 **		ctladdr -- address template to use to fill in these
532 **			addresses -- effective user/group id are
533 **			the important things.
534 **		sendq -- a pointer to the head of the send queue
535 **			to put these addresses in.
536 **
537 **	Returns:
538 **		open error status
539 **
540 **	Side Effects:
541 **		reads the :include: file and sends to everyone
542 **		listed in that file.
543 */
544 
545 static jmp_buf	CtxIncludeTimeout;
546 
547 int
548 include(fname, forwarding, ctladdr, sendq, e)
549 	char *fname;
550 	bool forwarding;
551 	ADDRESS *ctladdr;
552 	ADDRESS **sendq;
553 	ENVELOPE *e;
554 {
555 	register FILE *fp;
556 	char *oldto = e->e_to;
557 	char *oldfilename = FileName;
558 	int oldlinenumber = LineNumber;
559 	register EVENT *ev = NULL;
560 	int nincludes;
561 	int ret;
562 	char buf[MAXLINE];
563 	static int includetimeout();
564 
565 	if (tTd(27, 2))
566 		printf("include(%s)\n", fname);
567 
568 	/*
569 	**  If home directory is remote mounted but server is down,
570 	**  this can hang or give errors; use a timeout to avoid this
571 	*/
572 
573 	if (setjmp(CtxIncludeTimeout) != 0)
574 	{
575 		ctladdr->q_flags |= QQUEUEUP|QDONTSEND;
576 		errno = 0;
577 		usrerr("451 open timeout on %s", fname);
578 		return ETIMEDOUT;
579 	}
580 	ev = setevent((time_t) 60, includetimeout, 0);
581 
582 	/* if forwarding, the input file must be marked safe */
583 	if (forwarding && (ret = safefile(fname, ctladdr->q_uid, S_IREAD)) != 0)
584 	{
585 		/* don't use this .forward file */
586 		clrevent(ev);
587 		if (tTd(27, 4))
588 			printf("include: not safe (uid=%d): %s\n",
589 				ctladdr->q_uid, errstring(ret));
590 		return ret;
591 	}
592 
593 	fp = fopen(fname, "r");
594 	if (fp == NULL)
595 	{
596 		int ret = errno;
597 
598 		clrevent(ev);
599 		usrerr("550 Cannot open %s: %s", fname, errstring(ret));
600 		return ret;
601 	}
602 
603 	if (getctladdr(ctladdr) == NULL)
604 	{
605 		struct stat st;
606 
607 		if (fstat(fileno(fp), &st) < 0)
608 		{
609 			int ret = errno;
610 
611 			clrevent(ev);
612 			syserr("Cannot fstat %s!", fname);
613 			return ret;
614 		}
615 		ctladdr->q_uid = st.st_uid;
616 		ctladdr->q_gid = st.st_gid;
617 		ctladdr->q_flags |= QGOODUID;
618 	}
619 
620 	clrevent(ev);
621 
622 	if (bitset(EF_VRFYONLY, e->e_flags))
623 	{
624 		/* don't do any more now */
625 		xfclose(fp, "include", fname);
626 		return 0;
627 	}
628 
629 	/* read the file -- each line is a comma-separated list. */
630 	FileName = fname;
631 	LineNumber = 0;
632 	ctladdr->q_flags &= ~QSELFREF;
633 	nincludes = 0;
634 	while (fgets(buf, sizeof buf, fp) != NULL)
635 	{
636 		register char *p = strchr(buf, '\n');
637 
638 		LineNumber++;
639 		if (p != NULL)
640 			*p = '\0';
641 		if (buf[0] == '#' || buf[0] == '\0')
642 			continue;
643 		e->e_to = NULL;
644 		message("%s to %s",
645 			forwarding ? "forwarding" : "sending", buf);
646 #ifdef LOG
647 		if (forwarding && LogLevel > 9)
648 			syslog(LOG_INFO, "%s: forward %s => %s",
649 				e->e_id, oldto, buf);
650 #endif
651 
652 		AliasLevel++;
653 		nincludes += sendtolist(buf, ctladdr, sendq, e);
654 		AliasLevel--;
655 	}
656 	if (nincludes > 0 && !bitset(QSELFREF, ctladdr->q_flags))
657 	{
658 		if (tTd(27, 5))
659 		{
660 			printf("include: QDONTSEND ");
661 			printaddr(ctladdr, FALSE);
662 		}
663 		ctladdr->q_flags |= QDONTSEND;
664 	}
665 
666 	(void) xfclose(fp, "include", fname);
667 	FileName = oldfilename;
668 	LineNumber = oldlinenumber;
669 	return 0;
670 }
671 
672 static
673 includetimeout()
674 {
675 	longjmp(CtxIncludeTimeout, 1);
676 }
677 /*
678 **  SENDTOARGV -- send to an argument vector.
679 **
680 **	Parameters:
681 **		argv -- argument vector to send to.
682 **		e -- the current envelope.
683 **
684 **	Returns:
685 **		none.
686 **
687 **	Side Effects:
688 **		puts all addresses on the argument vector onto the
689 **			send queue.
690 */
691 
692 sendtoargv(argv, e)
693 	register char **argv;
694 	register ENVELOPE *e;
695 {
696 	register char *p;
697 
698 	while ((p = *argv++) != NULL)
699 	{
700 		(void) sendtolist(p, (ADDRESS *) NULL, &e->e_sendqueue, e);
701 	}
702 }
703 /*
704 **  GETCTLADDR -- get controlling address from an address header.
705 **
706 **	If none, get one corresponding to the effective userid.
707 **
708 **	Parameters:
709 **		a -- the address to find the controller of.
710 **
711 **	Returns:
712 **		the controlling address.
713 **
714 **	Side Effects:
715 **		none.
716 */
717 
718 ADDRESS *
719 getctladdr(a)
720 	register ADDRESS *a;
721 {
722 	while (a != NULL && !bitset(QGOODUID, a->q_flags))
723 		a = a->q_alias;
724 	return (a);
725 }
726