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[] = "@(#)envelope.c	6.4 (Berkeley) 01/28/93";
11 #endif /* not lint */
12 
13 #include <sys/types.h>
14 #include <sys/time.h>
15 #include <sys/stat.h>
16 #include <pwd.h>
17 #include <sys/file.h>
18 #include <sys/fcntl.h>
19 #include "sendmail.h"
20 
21 /*
22 **  NEWENVELOPE -- allocate a new envelope
23 **
24 **	Supports inheritance.
25 **
26 **	Parameters:
27 **		e -- the new envelope to fill in.
28 **
29 **	Returns:
30 **		e.
31 **
32 **	Side Effects:
33 **		none.
34 */
35 
36 ENVELOPE *
37 newenvelope(e)
38 	register ENVELOPE *e;
39 {
40 	register ENVELOPE *parent;
41 	extern putheader(), putbody();
42 	extern ENVELOPE BlankEnvelope;
43 
44 	parent = CurEnv;
45 	if (e == CurEnv && e->e_parent != NULL)
46 		parent = e->e_parent;
47 	clearenvelope(e, TRUE);
48 	if (e == CurEnv)
49 		bcopy((char *) &NullAddress, (char *) &e->e_from, sizeof e->e_from);
50 	else
51 		bcopy((char *) &CurEnv->e_from, (char *) &e->e_from, sizeof e->e_from);
52 	e->e_parent = parent;
53 	e->e_ctime = curtime();
54 	if (parent != NULL)
55 		e->e_msgpriority = parent->e_msgsize;
56 	e->e_puthdr = putheader;
57 	e->e_putbody = putbody;
58 	if (CurEnv->e_xfp != NULL)
59 		(void) fflush(CurEnv->e_xfp);
60 
61 	return (e);
62 }
63 /*
64 **  DROPENVELOPE -- deallocate an envelope.
65 **
66 **	Parameters:
67 **		e -- the envelope to deallocate.
68 **
69 **	Returns:
70 **		none.
71 **
72 **	Side Effects:
73 **		housekeeping necessary to dispose of an envelope.
74 **		Unlocks this queue file.
75 */
76 
77 dropenvelope(e)
78 	register ENVELOPE *e;
79 {
80 	bool queueit = FALSE;
81 	register ADDRESS *q;
82 
83 	if (tTd(50, 1))
84 	{
85 		printf("dropenvelope %x id=", e);
86 		xputs(e->e_id);
87 		printf(" flags=%o\n", e->e_flags);
88 	}
89 #ifdef LOG
90 	if (LogLevel > 12)
91 		syslog(LOG_DEBUG, "dropenvelope, id=%s, flags=%o, pid=%d",
92 				  e->e_id == NULL ? "(none)" : e->e_id,
93 				  e->e_flags, getpid());
94 #endif /* LOG */
95 
96 	/* we must have an id to remove disk files */
97 	if (e->e_id == NULL)
98 		return;
99 
100 	/*
101 	**  Extract state information from dregs of send list.
102 	*/
103 
104 	for (q = e->e_sendqueue; q != NULL; q = q->q_next)
105 	{
106 		if (bitset(QQUEUEUP, q->q_flags))
107 			queueit = TRUE;
108 	}
109 
110 	/*
111 	**  Send back return receipts as requested.
112 	*/
113 
114 	if (e->e_receiptto != NULL && bitset(EF_SENDRECEIPT, e->e_flags))
115 	{
116 		auto ADDRESS *rlist = NULL;
117 
118 		sendtolist(e->e_receiptto, (ADDRESS *) NULL, &rlist, e);
119 		(void) returntosender("Return receipt", rlist, FALSE, e);
120 	}
121 
122 	/*
123 	**  Arrange to send error messages if there are fatal errors.
124 	*/
125 
126 	if (bitset(EF_FATALERRS|EF_TIMEOUT, e->e_flags) && ErrorMode != EM_QUIET)
127 		savemail(e);
128 
129 	/*
130 	**  Instantiate or deinstantiate the queue.
131 	*/
132 
133 	if ((!queueit && !bitset(EF_KEEPQUEUE, e->e_flags)) ||
134 	    bitset(EF_CLRQUEUE, e->e_flags))
135 	{
136 		if (e->e_df != NULL)
137 			xunlink(e->e_df);
138 		xunlink(queuename(e, 'q'));
139 	}
140 	else if (queueit || !bitset(EF_INQUEUE, e->e_flags))
141 	{
142 #ifdef QUEUE
143 		queueup(e, FALSE, FALSE);
144 #else /* QUEUE */
145 		syserr("dropenvelope: queueup");
146 #endif /* QUEUE */
147 	}
148 
149 	/* now unlock the job */
150 	closexscript(e);
151 	unlockqueue(e);
152 
153 	/* make sure that this envelope is marked unused */
154 	e->e_id = e->e_df = NULL;
155 	if (e->e_dfp != NULL)
156 		(void) fclose(e->e_dfp);
157 	e->e_dfp = NULL;
158 
159 #ifdef LOG
160 	if (LogLevel >= 10)
161 		syslog(LOG_INFO, "%s: done", e->e_id);
162 #endif /* LOG */
163 }
164 /*
165 **  CLEARENVELOPE -- clear an envelope without unlocking
166 **
167 **	This is normally used by a child process to get a clean
168 **	envelope without disturbing the parent.
169 **
170 **	Parameters:
171 **		e -- the envelope to clear.
172 **		fullclear - if set, the current envelope is total
173 **			garbage and should be ignored; otherwise,
174 **			release any resources it may indicate.
175 **
176 **	Returns:
177 **		none.
178 **
179 **	Side Effects:
180 **		Closes files associated with the envelope.
181 **		Marks the envelope as unallocated.
182 */
183 
184 clearenvelope(e, fullclear)
185 	register ENVELOPE *e;
186 	bool fullclear;
187 {
188 	register HDR *bh;
189 	register HDR **nhp;
190 	extern ENVELOPE BlankEnvelope;
191 
192 	if (!fullclear)
193 	{
194 		/* clear out any file information */
195 		if (e->e_xfp != NULL)
196 			(void) fclose(e->e_xfp);
197 		if (e->e_dfp != NULL)
198 			(void) fclose(e->e_dfp);
199 	}
200 
201 	/* now clear out the data */
202 	STRUCTCOPY(BlankEnvelope, *e);
203 	bh = BlankEnvelope.e_header;
204 	nhp = &e->e_header;
205 	while (bh != NULL)
206 	{
207 		*nhp = (HDR *) xalloc(sizeof *bh);
208 		bcopy((char *) bh, (char *) *nhp, sizeof *bh);
209 		bh = bh->h_link;
210 		nhp = &(*nhp)->h_link;
211 	}
212 }
213 /*
214 **  INITSYS -- initialize instantiation of system
215 **
216 **	In Daemon mode, this is done in the child.
217 **
218 **	Parameters:
219 **		none.
220 **
221 **	Returns:
222 **		none.
223 **
224 **	Side Effects:
225 **		Initializes the system macros, some global variables,
226 **		etc.  In particular, the current time in various
227 **		forms is set.
228 */
229 
230 initsys(e)
231 	register ENVELOPE *e;
232 {
233 	static char cbuf[5];			/* holds hop count */
234 	static char pbuf[10];			/* holds pid */
235 #ifdef TTYNAME
236 	static char ybuf[10];			/* holds tty id */
237 	register char *p;
238 #endif /* TTYNAME */
239 	extern char *ttyname();
240 	extern char *macvalue();
241 	extern char Version[];
242 
243 	/*
244 	**  Give this envelope a reality.
245 	**	I.e., an id, a transcript, and a creation time.
246 	*/
247 
248 	openxscript(e);
249 	e->e_ctime = curtime();
250 
251 	/*
252 	**  Set OutChannel to something useful if stdout isn't it.
253 	**	This arranges that any extra stuff the mailer produces
254 	**	gets sent back to the user on error (because it is
255 	**	tucked away in the transcript).
256 	*/
257 
258 	if (OpMode == MD_DAEMON && QueueRun)
259 		OutChannel = e->e_xfp;
260 
261 	/*
262 	**  Set up some basic system macros.
263 	*/
264 
265 	/* process id */
266 	(void) sprintf(pbuf, "%d", getpid());
267 	define('p', pbuf, e);
268 
269 	/* hop count */
270 	(void) sprintf(cbuf, "%d", e->e_hopcount);
271 	define('c', cbuf, e);
272 
273 	/* time as integer, unix time, arpa time */
274 	settime(e);
275 
276 #ifdef TTYNAME
277 	/* tty name */
278 	if (macvalue('y', e) == NULL)
279 	{
280 		p = ttyname(2);
281 		if (p != NULL)
282 		{
283 			if (strrchr(p, '/') != NULL)
284 				p = strrchr(p, '/') + 1;
285 			(void) strcpy(ybuf, p);
286 			define('y', ybuf, e);
287 		}
288 	}
289 #endif /* TTYNAME */
290 }
291 /*
292 **  SETTIME -- set the current time.
293 **
294 **	Parameters:
295 **		none.
296 **
297 **	Returns:
298 **		none.
299 **
300 **	Side Effects:
301 **		Sets the various time macros -- $a, $b, $d, $t.
302 */
303 
304 settime(e)
305 	register ENVELOPE *e;
306 {
307 	register char *p;
308 	auto time_t now;
309 	static char tbuf[20];			/* holds "current" time */
310 	static char dbuf[30];			/* holds ctime(tbuf) */
311 	register struct tm *tm;
312 	extern char *arpadate();
313 	extern struct tm *gmtime();
314 	extern char *macvalue();
315 
316 	now = curtime();
317 	tm = gmtime(&now);
318 	(void) sprintf(tbuf, "%04d%02d%02d%02d%02d", tm->tm_year + 1900,
319 			tm->tm_mon+1, tm->tm_mday, tm->tm_hour, tm->tm_min);
320 	define('t', tbuf, e);
321 	(void) strcpy(dbuf, ctime(&now));
322 	*strchr(dbuf, '\n') = '\0';
323 	if (macvalue('d', e) == NULL)
324 		define('d', dbuf, e);
325 	p = newstr(arpadate(dbuf));
326 	if (macvalue('a', e) == NULL)
327 		define('a', p, e);
328 	define('b', p, e);
329 }
330 /*
331 **  OPENXSCRIPT -- Open transcript file
332 **
333 **	Creates a transcript file for possible eventual mailing or
334 **	sending back.
335 **
336 **	Parameters:
337 **		e -- the envelope to create the transcript in/for.
338 **
339 **	Returns:
340 **		none
341 **
342 **	Side Effects:
343 **		Creates the transcript file.
344 */
345 
346 openxscript(e)
347 	register ENVELOPE *e;
348 {
349 	register char *p;
350 	int fd;
351 
352 # ifdef LOG
353 	if (LogLevel > 19)
354 		syslog(LOG_DEBUG, "%s: openx%s", e->e_id, e->e_xfp == NULL ? "" : " (no)");
355 # endif /* LOG */
356 	if (e->e_xfp != NULL)
357 		return;
358 	p = queuename(e, 'x');
359 	fd = open(p, O_WRONLY|O_CREAT, 0644);
360 	if (fd < 0)
361 		syserr("Can't create %s", p);
362 	else
363 		e->e_xfp = fdopen(fd, "w");
364 }
365 /*
366 **  CLOSEXSCRIPT -- close the transcript file.
367 **
368 **	Parameters:
369 **		e -- the envelope containing the transcript to close.
370 **
371 **	Returns:
372 **		none.
373 **
374 **	Side Effects:
375 **		none.
376 */
377 
378 closexscript(e)
379 	register ENVELOPE *e;
380 {
381 	if (e->e_xfp == NULL)
382 		return;
383 	(void) fclose(e->e_xfp);
384 	e->e_xfp = NULL;
385 }
386 /*
387 **  SETSENDER -- set the person who this message is from
388 **
389 **	Under certain circumstances allow the user to say who
390 **	s/he is (using -f or -r).  These are:
391 **	1.  The user's uid is zero (root).
392 **	2.  The user's login name is in an approved list (typically
393 **	    from a network server).
394 **	3.  The address the user is trying to claim has a
395 **	    "!" character in it (since #2 doesn't do it for
396 **	    us if we are dialing out for UUCP).
397 **	A better check to replace #3 would be if the
398 **	effective uid is "UUCP" -- this would require me
399 **	to rewrite getpwent to "grab" uucp as it went by,
400 **	make getname more nasty, do another passwd file
401 **	scan, or compile the UID of "UUCP" into the code,
402 **	all of which are reprehensible.
403 **
404 **	Assuming all of these fail, we figure out something
405 **	ourselves.
406 **
407 **	Parameters:
408 **		from -- the person we would like to believe this message
409 **			is from, as specified on the command line.
410 **		e -- the envelope in which we would like the sender set.
411 **
412 **	Returns:
413 **		none.
414 **
415 **	Side Effects:
416 **		sets sendmail's notion of who the from person is.
417 */
418 
419 setsender(from, e)
420 	char *from;
421 	register ENVELOPE *e;
422 {
423 	register char **pvp;
424 	char *realname = NULL;
425 	register struct passwd *pw;
426 	char buf[MAXNAME];
427 	char pvpbuf[PSBUFSIZE];
428 	extern struct passwd *getpwnam();
429 	extern char *macvalue();
430 	extern char **prescan();
431 	extern bool safefile();
432 	extern char *FullName;
433 
434 	if (tTd(45, 1))
435 		printf("setsender(%s)\n", from == NULL ? "" : from);
436 
437 	/*
438 	**  Figure out the real user executing us.
439 	**	Username can return errno != 0 on non-errors.
440 	*/
441 
442 	if (QueueRun || OpMode == MD_SMTP)
443 		realname = from;
444 	if (realname == NULL || realname[0] == '\0')
445 	{
446 		extern char *username();
447 
448 		realname = username();
449 	}
450 
451 	/*
452 	**  Determine if this real person is allowed to alias themselves.
453 	*/
454 
455 	if (from != NULL)
456 	{
457 		extern bool trusteduser();
458 
459 		if (!trusteduser(realname) && getuid() != geteuid() &&
460 		    strchr(from, '!') == NULL && getuid() != 0)
461 		{
462 			/* network sends -r regardless (why why why?) */
463 			/* syserr("%s, you cannot use the -f flag", realname); */
464 			from = NULL;
465 		}
466 	}
467 
468 /*
469 	SuprErrs = TRUE;
470 */
471 	if (from == NULL || parseaddr(from, &e->e_from, 1, '\0', e) == NULL)
472 	{
473 		/* log garbage addresses for traceback */
474 # ifdef LOG
475 		if (from != NULL && LogLevel >= 1)
476 		{
477 			char *host = RealHostName;
478 
479 			if (host == NULL)
480 				host = MyHostName;
481 			syslog(LOG_NOTICE,
482 				"from=%s unparseable, received from %s@%s",
483 				from, realname, host);
484 		}
485 # endif /* LOG */
486 		if (from != NULL)
487 			SuprErrs = TRUE;
488 		if (from == realname ||
489 		    parseaddr(from = newstr(realname), &e->e_from, 1, '\0', e) == NULL)
490 		{
491 			SuprErrs = TRUE;
492 			if (parseaddr("postmaster", &e->e_from, 1, '\0', e) == NULL)
493 				syserr("setsender: can't even parse postmaster!");
494 		}
495 	}
496 	else
497 		FromFlag = TRUE;
498 	e->e_from.q_flags |= QDONTSEND;
499 	if (tTd(45, 5))
500 	{
501 		printf("setsender: QDONTSEND ");
502 		printaddr(&e->e_from, FALSE);
503 	}
504 	loweraddr(&e->e_from);
505 	SuprErrs = FALSE;
506 
507 	pvp = NULL;
508 	if (e->e_from.q_mailer == LocalMailer)
509 	{
510 # ifdef USERDB
511 		register char *p;
512 		extern char *udbsender();
513 # endif
514 
515 		/* if the user has given fullname already, don't redefine */
516 		if (FullName == NULL)
517 			FullName = macvalue('x', e);
518 		if (FullName != NULL && FullName[0] == '\0')
519 			FullName = NULL;
520 
521 # ifdef USERDB
522 		p = udbsender(from);
523 
524 		if (p != NULL)
525 		{
526 			/*
527 			**  We have an alternate address for the sender
528 			*/
529 
530 			pvp = prescan(p, '\0', pvpbuf);
531 		}
532 # endif /* USERDB */
533 
534 		if ((pw = getpwnam(e->e_from.q_user)) != NULL)
535 		{
536 			/*
537 			**  Process passwd file entry.
538 			*/
539 
540 
541 			/* extract home directory */
542 			e->e_from.q_home = newstr(pw->pw_dir);
543 			define('z', e->e_from.q_home, e);
544 
545 			/* extract user and group id */
546 			e->e_from.q_uid = pw->pw_uid;
547 			e->e_from.q_gid = pw->pw_gid;
548 
549 			/* extract full name from passwd file */
550 			if (FullName == NULL && pw->pw_gecos != NULL &&
551 			    strcmp(pw->pw_name, e->e_from.q_user) == 0)
552 			{
553 				buildfname(pw->pw_gecos, e->e_from.q_user, buf);
554 				if (buf[0] != '\0')
555 					FullName = newstr(buf);
556 			}
557 		}
558 		if (FullName != NULL)
559 			define('x', FullName, e);
560 	}
561 	else
562 	{
563 		if (e->e_from.q_home == NULL)
564 			e->e_from.q_home = getenv("HOME");
565 		e->e_from.q_uid = getuid();
566 		e->e_from.q_gid = getgid();
567 	}
568 
569 	/*
570 	**  Rewrite the from person to dispose of possible implicit
571 	**	links in the net.
572 	*/
573 
574 	if (pvp == NULL)
575 		pvp = prescan(from, '\0', pvpbuf);
576 	if (pvp == NULL)
577 	{
578 # ifdef LOG
579 		if (LogLevel >= 1)
580 			syslog(LOG_NOTICE, "cannot prescan from (%s)", from);
581 # endif
582 		usrerr("cannot prescan from (%s)", from);
583 		finis();
584 	}
585 	rewrite(pvp, 3);
586 	rewrite(pvp, 1);
587 	rewrite(pvp, 4);
588 	cataddr(pvp, buf, sizeof buf);
589 	e->e_sender = e->e_returnpath = newstr(buf);
590 
591 	define('f', e->e_sender, e);
592 
593 	/* save the domain spec if this mailer wants it */
594 	if (e->e_from.q_mailer != NULL &&
595 	    bitnset(M_CANONICAL, e->e_from.q_mailer->m_flags))
596 	{
597 		extern char **copyplist();
598 
599 		while (*pvp != NULL && strcmp(*pvp, "@") != 0)
600 			pvp++;
601 		if (*pvp != NULL)
602 			e->e_fromdomain = copyplist(pvp, TRUE);
603 	}
604 }
605 /*
606 **  TRUSTEDUSER -- tell us if this user is to be trusted.
607 **
608 **	Parameters:
609 **		user -- the user to be checked.
610 **
611 **	Returns:
612 **		TRUE if the user is in an approved list.
613 **		FALSE otherwise.
614 **
615 **	Side Effects:
616 **		none.
617 */
618 
619 bool
620 trusteduser(user)
621 	char *user;
622 {
623 	register char **ulist;
624 	extern char *TrustedUsers[];
625 
626 	for (ulist = TrustedUsers; *ulist != NULL; ulist++)
627 		if (strcmp(*ulist, user) == 0)
628 			return (TRUE);
629 	return (FALSE);
630 }
631