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	5.31 (Berkeley) 09/09/92";
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 "sendmail.h"
19 
20 /*
21 **  NEWENVELOPE -- allocate a new envelope
22 **
23 **	Supports inheritance.
24 **
25 **	Parameters:
26 **		e -- the new envelope to fill in.
27 **
28 **	Returns:
29 **		e.
30 **
31 **	Side Effects:
32 **		none.
33 */
34 
35 ENVELOPE *
36 newenvelope(e)
37 	register ENVELOPE *e;
38 {
39 	register ENVELOPE *parent;
40 	extern putheader(), putbody();
41 	extern ENVELOPE BlankEnvelope;
42 
43 	parent = CurEnv;
44 	if (e == CurEnv && e->e_parent != NULL)
45 		parent = e->e_parent;
46 	clearenvelope(e, TRUE);
47 	if (e == CurEnv)
48 		bcopy((char *) &NullAddress, (char *) &e->e_from, sizeof e->e_from);
49 	else
50 		bcopy((char *) &CurEnv->e_from, (char *) &e->e_from, sizeof e->e_from);
51 	e->e_parent = parent;
52 	e->e_ctime = curtime();
53 	if (parent != NULL)
54 		e->e_msgpriority = parent->e_msgsize;
55 	e->e_puthdr = putheader;
56 	e->e_putbody = putbody;
57 	if (CurEnv->e_xfp != NULL)
58 		(void) fflush(CurEnv->e_xfp);
59 
60 	return (e);
61 }
62 /*
63 **  DROPENVELOPE -- deallocate an envelope.
64 **
65 **	Parameters:
66 **		e -- the envelope to deallocate.
67 **
68 **	Returns:
69 **		none.
70 **
71 **	Side Effects:
72 **		housekeeping necessary to dispose of an envelope.
73 **		Unlocks this queue file.
74 */
75 
76 dropenvelope(e)
77 	register ENVELOPE *e;
78 {
79 	bool queueit = FALSE;
80 	register ADDRESS *q;
81 
82 	if (tTd(50, 1))
83 	{
84 		printf("dropenvelope %x id=", e);
85 		xputs(e->e_id);
86 		printf(" flags=%o\n", e->e_flags);
87 	}
88 #ifdef LOG
89 	if (LogLevel > 12)
90 		syslog(LOG_DEBUG, "dropenvelope, id=%s, flags=%o, pid=%d",
91 				  e->e_id == NULL ? "(none)" : e->e_id,
92 				  e->e_flags, getpid());
93 #endif LOG
94 
95 	/* we must have an id to remove disk files */
96 	if (e->e_id == NULL)
97 		return;
98 
99 	/*
100 	**  Extract state information from dregs of send list.
101 	*/
102 
103 	for (q = e->e_sendqueue; q != NULL; q = q->q_next)
104 	{
105 		if (bitset(QQUEUEUP, q->q_flags))
106 			queueit = TRUE;
107 	}
108 
109 	/*
110 	**  Send back return receipts as requested.
111 	*/
112 
113 	if (e->e_receiptto != NULL && bitset(EF_SENDRECEIPT, e->e_flags))
114 	{
115 		auto ADDRESS *rlist = NULL;
116 
117 		sendtolist(e->e_receiptto, (ADDRESS *) NULL, &rlist, e);
118 		(void) returntosender("Return receipt", rlist, FALSE, e);
119 	}
120 
121 	/*
122 	**  Arrange to send error messages if there are fatal errors.
123 	*/
124 
125 	if (bitset(EF_FATALERRS|EF_TIMEOUT, e->e_flags) && ErrorMode != EM_QUIET)
126 		savemail(e);
127 
128 	/*
129 	**  Instantiate or deinstantiate the queue.
130 	*/
131 
132 	if ((!queueit && !bitset(EF_KEEPQUEUE, e->e_flags)) ||
133 	    bitset(EF_CLRQUEUE, e->e_flags))
134 	{
135 		if (e->e_df != NULL)
136 			xunlink(e->e_df);
137 		xunlink(queuename(e, 'q'));
138 	}
139 	else if (queueit || !bitset(EF_INQUEUE, e->e_flags))
140 	{
141 #ifdef QUEUE
142 		queueup(e, FALSE, FALSE);
143 #else QUEUE
144 		syserr("dropenvelope: queueup");
145 #endif QUEUE
146 	}
147 
148 	/* now unlock the job */
149 	closexscript(e);
150 	unlockqueue(e);
151 
152 	/* make sure that this envelope is marked unused */
153 	e->e_id = e->e_df = NULL;
154 	if (e->e_dfp != NULL)
155 		(void) fclose(e->e_dfp);
156 	e->e_dfp = NULL;
157 }
158 /*
159 **  CLEARENVELOPE -- clear an envelope without unlocking
160 **
161 **	This is normally used by a child process to get a clean
162 **	envelope without disturbing the parent.
163 **
164 **	Parameters:
165 **		e -- the envelope to clear.
166 **		fullclear - if set, the current envelope is total
167 **			garbage and should be ignored; otherwise,
168 **			release any resources it may indicate.
169 **
170 **	Returns:
171 **		none.
172 **
173 **	Side Effects:
174 **		Closes files associated with the envelope.
175 **		Marks the envelope as unallocated.
176 */
177 
178 clearenvelope(e, fullclear)
179 	register ENVELOPE *e;
180 	bool fullclear;
181 {
182 	register HDR *bh;
183 	register HDR **nhp;
184 	extern ENVELOPE BlankEnvelope;
185 
186 	if (!fullclear)
187 	{
188 		/* clear out any file information */
189 		if (e->e_xfp != NULL)
190 			(void) fclose(e->e_xfp);
191 		if (e->e_dfp != NULL)
192 			(void) fclose(e->e_dfp);
193 	}
194 
195 	/* now clear out the data */
196 	STRUCTCOPY(BlankEnvelope, *e);
197 	bh = BlankEnvelope.e_header;
198 	nhp = &e->e_header;
199 	while (bh != NULL)
200 	{
201 		*nhp = (HDR *) xalloc(sizeof *bh);
202 		bcopy((char *) bh, (char *) *nhp, sizeof *bh);
203 		bh = bh->h_link;
204 		nhp = &(*nhp)->h_link;
205 	}
206 }
207 /*
208 **  INITSYS -- initialize instantiation of system
209 **
210 **	In Daemon mode, this is done in the child.
211 **
212 **	Parameters:
213 **		none.
214 **
215 **	Returns:
216 **		none.
217 **
218 **	Side Effects:
219 **		Initializes the system macros, some global variables,
220 **		etc.  In particular, the current time in various
221 **		forms is set.
222 */
223 
224 initsys(e)
225 	register ENVELOPE *e;
226 {
227 	static char cbuf[5];			/* holds hop count */
228 	static char pbuf[10];			/* holds pid */
229 #ifdef TTYNAME
230 	static char ybuf[10];			/* holds tty id */
231 	register char *p;
232 #endif TTYNAME
233 	extern char *ttyname();
234 	extern char *macvalue();
235 	extern char Version[];
236 
237 	/*
238 	**  Give this envelope a reality.
239 	**	I.e., an id, a transcript, and a creation time.
240 	*/
241 
242 	openxscript(e);
243 	e->e_ctime = curtime();
244 
245 	/*
246 	**  Set OutChannel to something useful if stdout isn't it.
247 	**	This arranges that any extra stuff the mailer produces
248 	**	gets sent back to the user on error (because it is
249 	**	tucked away in the transcript).
250 	*/
251 
252 	if (OpMode == MD_DAEMON && QueueRun)
253 		OutChannel = e->e_xfp;
254 
255 	/*
256 	**  Set up some basic system macros.
257 	*/
258 
259 	/* process id */
260 	(void) sprintf(pbuf, "%d", getpid());
261 	define('p', pbuf, e);
262 
263 	/* hop count */
264 	(void) sprintf(cbuf, "%d", e->e_hopcount);
265 	define('c', cbuf, e);
266 
267 	/* time as integer, unix time, arpa time */
268 	settime(e);
269 
270 #ifdef TTYNAME
271 	/* tty name */
272 	if (macvalue('y', e) == NULL)
273 	{
274 		p = ttyname(2);
275 		if (p != NULL)
276 		{
277 			if (rindex(p, '/') != NULL)
278 				p = rindex(p, '/') + 1;
279 			(void) strcpy(ybuf, p);
280 			define('y', ybuf, e);
281 		}
282 	}
283 #endif TTYNAME
284 }
285 /*
286 **  SETTIME -- set the current time.
287 **
288 **	Parameters:
289 **		none.
290 **
291 **	Returns:
292 **		none.
293 **
294 **	Side Effects:
295 **		Sets the various time macros -- $a, $b, $d, $t.
296 */
297 
298 settime(e)
299 	register ENVELOPE *e;
300 {
301 	register char *p;
302 	auto time_t now;
303 	static char tbuf[20];			/* holds "current" time */
304 	static char dbuf[30];			/* holds ctime(tbuf) */
305 	register struct tm *tm;
306 	extern char *arpadate();
307 	extern struct tm *gmtime();
308 	extern char *macvalue();
309 
310 	now = curtime();
311 	tm = gmtime(&now);
312 	(void) sprintf(tbuf, "%02d%02d%02d%02d%02d", tm->tm_year, tm->tm_mon+1,
313 			tm->tm_mday, tm->tm_hour, tm->tm_min);
314 	define('t', tbuf, e);
315 	(void) strcpy(dbuf, ctime(&now));
316 	*index(dbuf, '\n') = '\0';
317 	if (macvalue('d', e) == NULL)
318 		define('d', dbuf, e);
319 	p = newstr(arpadate(dbuf));
320 	if (macvalue('a', e) == NULL)
321 		define('a', p, e);
322 	define('b', p, e);
323 }
324 /*
325 **  OPENXSCRIPT -- Open transcript file
326 **
327 **	Creates a transcript file for possible eventual mailing or
328 **	sending back.
329 **
330 **	Parameters:
331 **		e -- the envelope to create the transcript in/for.
332 **
333 **	Returns:
334 **		none
335 **
336 **	Side Effects:
337 **		Creates the transcript file.
338 */
339 
340 openxscript(e)
341 	register ENVELOPE *e;
342 {
343 	register char *p;
344 	int fd;
345 
346 # ifdef LOG
347 	if (LogLevel > 19)
348 		syslog(LOG_DEBUG, "%s: openx%s", e->e_id, e->e_xfp == NULL ? "" : " (no)");
349 # endif LOG
350 	if (e->e_xfp != NULL)
351 		return;
352 	p = queuename(e, 'x');
353 	fd = open(p, O_WRONLY|O_CREAT, 0644);
354 	if (fd < 0)
355 		syserr("Can't create %s", p);
356 	else
357 		e->e_xfp = fdopen(fd, "w");
358 }
359 /*
360 **  CLOSEXSCRIPT -- close the transcript file.
361 **
362 **	Parameters:
363 **		e -- the envelope containing the transcript to close.
364 **
365 **	Returns:
366 **		none.
367 **
368 **	Side Effects:
369 **		none.
370 */
371 
372 closexscript(e)
373 	register ENVELOPE *e;
374 {
375 	if (e->e_xfp == NULL)
376 		return;
377 	(void) fclose(e->e_xfp);
378 	e->e_xfp = NULL;
379 }
380 /*
381 **  SETSENDER -- set the person who this message is from
382 **
383 **	Under certain circumstances allow the user to say who
384 **	s/he is (using -f or -r).  These are:
385 **	1.  The user's uid is zero (root).
386 **	2.  The user's login name is in an approved list (typically
387 **	    from a network server).
388 **	3.  The address the user is trying to claim has a
389 **	    "!" character in it (since #2 doesn't do it for
390 **	    us if we are dialing out for UUCP).
391 **	A better check to replace #3 would be if the
392 **	effective uid is "UUCP" -- this would require me
393 **	to rewrite getpwent to "grab" uucp as it went by,
394 **	make getname more nasty, do another passwd file
395 **	scan, or compile the UID of "UUCP" into the code,
396 **	all of which are reprehensible.
397 **
398 **	Assuming all of these fail, we figure out something
399 **	ourselves.
400 **
401 **	Parameters:
402 **		from -- the person we would like to believe this message
403 **			is from, as specified on the command line.
404 **		e -- the envelope in which we would like the sender set.
405 **
406 **	Returns:
407 **		none.
408 **
409 **	Side Effects:
410 **		sets sendmail's notion of who the from person is.
411 */
412 
413 setsender(from, e)
414 	char *from;
415 	register ENVELOPE *e;
416 {
417 	register char **pvp;
418 	char *realname = NULL;
419 	register struct passwd *pw;
420 	char buf[MAXNAME];
421 	char pvpbuf[PSBUFSIZE];
422 	extern struct passwd *getpwnam();
423 	extern char *macvalue();
424 	extern char **prescan();
425 	extern bool safefile();
426 	extern char *FullName;
427 
428 	if (tTd(45, 1))
429 		printf("setsender(%s)\n", from == NULL ? "" : from);
430 
431 	/*
432 	**  Figure out the real user executing us.
433 	**	Username can return errno != 0 on non-errors.
434 	*/
435 
436 	if (QueueRun || OpMode == MD_SMTP)
437 		realname = from;
438 	if (realname == NULL || realname[0] == '\0')
439 	{
440 		extern char *username();
441 
442 		realname = username();
443 	}
444 
445 	/*
446 	**  Determine if this real person is allowed to alias themselves.
447 	*/
448 
449 	if (from != NULL)
450 	{
451 		extern bool trusteduser();
452 
453 		if (!trusteduser(realname) && getuid() != geteuid() &&
454 		    index(from, '!') == NULL && getuid() != 0)
455 		{
456 			/* network sends -r regardless (why why why?) */
457 			/* syserr("%s, you cannot use the -f flag", realname); */
458 			from = NULL;
459 		}
460 	}
461 
462 	SuprErrs = TRUE;
463 	if (from == NULL || parseaddr(from, &e->e_from, 1, '\0', e) == NULL)
464 	{
465 		/* log garbage addresses for traceback */
466 # ifdef LOG
467 		if (from != NULL && LogLevel >= 1)
468 		{
469 			char *host = RealHostName;
470 
471 			if (host == NULL)
472 				host = MyHostName;
473 			syslog(LOG_NOTICE,
474 				"from=%s unparseable, received from %s@%s",
475 				from, realname, host);
476 		}
477 # endif LOG
478 		from = newstr(realname);
479 		if (parseaddr(from, &e->e_from, 1, '\0', e) == NULL &&
480 		    parseaddr("postmaster", &e->e_from, 1, '\0', e) == NULL)
481 		{
482 			syserr("setsender: can't even parse postmaster!");
483 		}
484 	}
485 	else
486 		FromFlag = TRUE;
487 	e->e_from.q_flags |= QDONTSEND;
488 	loweraddr(&e->e_from);
489 	SuprErrs = FALSE;
490 
491 	pvp = NULL;
492 	if (e->e_from.q_mailer == LocalMailer)
493 	{
494 # ifdef USERDB
495 		register char *p;
496 		extern char *udbsender();
497 # endif
498 
499 		/* if the user has given fullname already, don't redefine */
500 		if (FullName == NULL)
501 			FullName = macvalue('x', e);
502 		if (FullName != NULL && FullName[0] == '\0')
503 			FullName = NULL;
504 
505 # ifdef USERDB
506 		p = udbsender(from);
507 
508 		if (p != NULL)
509 		{
510 			/*
511 			**  We have an alternate address for the sender
512 			*/
513 
514 			pvp = prescan(p, '\0', pvpbuf);
515 		}
516 # endif /* USERDB */
517 
518 		if ((pw = getpwnam(e->e_from.q_user)) != NULL)
519 		{
520 			/*
521 			**  Process passwd file entry.
522 			*/
523 
524 
525 			/* extract home directory */
526 			e->e_from.q_home = newstr(pw->pw_dir);
527 			define('z', e->e_from.q_home, e);
528 
529 			/* extract user and group id */
530 			e->e_from.q_uid = pw->pw_uid;
531 			e->e_from.q_gid = pw->pw_gid;
532 
533 			/* extract full name from passwd file */
534 			if (FullName == NULL && pw->pw_gecos != NULL &&
535 			    strcmp(pw->pw_name, e->e_from.q_user) == 0)
536 			{
537 				buildfname(pw->pw_gecos, e->e_from.q_user, buf);
538 				if (buf[0] != '\0')
539 					FullName = newstr(buf);
540 			}
541 		}
542 		if (FullName != NULL)
543 			define('x', FullName, e);
544 	}
545 	else
546 	{
547 		if (e->e_from.q_home == NULL)
548 			e->e_from.q_home = getenv("HOME");
549 		e->e_from.q_uid = getuid();
550 		e->e_from.q_gid = getgid();
551 	}
552 
553 	/*
554 	**  Rewrite the from person to dispose of possible implicit
555 	**	links in the net.
556 	*/
557 
558 	if (pvp == NULL)
559 		pvp = prescan(from, '\0', pvpbuf);
560 	if (pvp == NULL)
561 	{
562 # ifdef LOG
563 		if (LogLevel >= 1)
564 			syslog(LOG_NOTICE, "cannot prescan from (%s)", from);
565 # endif
566 		usrerr("cannot prescan from (%s)", from);
567 		finis();
568 	}
569 	rewrite(pvp, 3);
570 	rewrite(pvp, 1);
571 	rewrite(pvp, 4);
572 	cataddr(pvp, buf, sizeof buf);
573 	e->e_sender = e->e_returnpath = newstr(buf);
574 
575 	define('f', e->e_sender, e);
576 
577 	/* save the domain spec if this mailer wants it */
578 	if (e->e_from.q_mailer != NULL &&
579 	    bitnset(M_CANONICAL, e->e_from.q_mailer->m_flags))
580 	{
581 		extern char **copyplist();
582 
583 		while (*pvp != NULL && strcmp(*pvp, "@") != 0)
584 			pvp++;
585 		if (*pvp != NULL)
586 			e->e_fromdomain = copyplist(pvp, TRUE);
587 	}
588 }
589 /*
590 **  TRUSTEDUSER -- tell us if this user is to be trusted.
591 **
592 **	Parameters:
593 **		user -- the user to be checked.
594 **
595 **	Returns:
596 **		TRUE if the user is in an approved list.
597 **		FALSE otherwise.
598 **
599 **	Side Effects:
600 **		none.
601 */
602 
603 bool
604 trusteduser(user)
605 	char *user;
606 {
607 	register char **ulist;
608 	extern char *TrustedUsers[];
609 
610 	for (ulist = TrustedUsers; *ulist != NULL; ulist++)
611 		if (strcmp(*ulist, user) == 0)
612 			return (TRUE);
613 	return (FALSE);
614 }
615