1 #include <pwd.h>
2 #include <time.h>
3 #include "sendmail.h"
4 #include <sys/stat.h>
5 
6 SCCSID(@(#)envelope.c	3.6		01/08/83);
7 
8 /*
9 **  NEWENVELOPE -- allocate a new envelope
10 **
11 **	Supports inheritance.
12 **
13 **	Parameters:
14 **		e -- the new envelope to fill in.
15 **
16 **	Returns:
17 **		e.
18 **
19 **	Side Effects:
20 **		none.
21 */
22 
23 ENVELOPE *
24 newenvelope(e)
25 	register ENVELOPE *e;
26 {
27 	register HDR *bh;
28 	register HDR **nhp;
29 	register ENVELOPE *parent;
30 	extern putheader(), putbody();
31 	extern ENVELOPE BlankEnvelope;
32 
33 	parent = CurEnv;
34 	if (e == CurEnv)
35 		parent = e->e_parent;
36 	clear((char *) e, sizeof *e);
37 	bmove((char *) &CurEnv->e_from, (char *) &e->e_from, sizeof e->e_from);
38 	e->e_parent = parent;
39 	e->e_ctime = curtime();
40 	e->e_puthdr = putheader;
41 	e->e_putbody = putbody;
42 	bh = BlankEnvelope.e_header;
43 	nhp = &e->e_header;
44 	while (bh != NULL)
45 	{
46 		*nhp = (HDR *) xalloc(sizeof *bh);
47 		bmove((char *) bh, (char *) *nhp, sizeof *bh);
48 		bh = bh->h_link;
49 		nhp = &(*nhp)->h_link;
50 	}
51 	if (CurEnv->e_xfp != NULL)
52 		(void) fflush(CurEnv->e_xfp);
53 
54 	return (e);
55 }
56 /*
57 **  DROPENVELOPE -- deallocate an envelope.
58 **
59 **	Parameters:
60 **		e -- the envelope to deallocate.
61 **
62 **	Returns:
63 **		none.
64 **
65 **	Side Effects:
66 **		housekeeping necessary to dispose of an envelope.
67 **		Unlocks this queue file.
68 */
69 
70 dropenvelope(e)
71 	register ENVELOPE *e;
72 {
73 	bool queueit = FALSE;
74 	register ADDRESS *q;
75 
76 #ifdef DEBUG
77 	if (tTd(50, 1))
78 	{
79 		printf("dropenvelope %x id=", e);
80 		xputs(e->e_id);
81 		printf(" flags=%o\n", e->e_flags);
82 	}
83 #endif DEBUG
84 #ifdef LOG
85 	if (LogLevel > 10)
86 		syslog(LOG_DEBUG, "dropenvelope, id=%s, flags=%o, pid=%d",
87 				  e->e_id == NULL ? "(none)" : e->e_id,
88 				  e->e_flags, getpid());
89 #endif LOG
90 
91 	/* we must have an id to remove disk files */
92 	if (e->e_id == NULL)
93 		return;
94 
95 	/*
96 	**  Extract state information from dregs of send list.
97 	*/
98 
99 	for (q = e->e_sendqueue; q != NULL; q = q->q_next)
100 	{
101 		if (bitset(QQUEUEUP, q->q_flags))
102 			queueit = TRUE;
103 	}
104 
105 	/*
106 	**  Send back return receipts as requested.
107 	*/
108 
109 	if (e->e_receiptto != NULL && bitset(EF_SENDRECEIPT, e->e_flags))
110 	{
111 		auto ADDRESS *rlist;
112 
113 		sendtolist(CurEnv->e_receiptto, (ADDRESS *) NULL, &rlist);
114 		(void) returntosender("Return receipt", rlist, FALSE);
115 	}
116 
117 	/*
118 	**  Arrange to send error messages if there are fatal errors.
119 	*/
120 
121 	if (bitset(EF_FATALERRS|EF_TIMEOUT, e->e_flags))
122 		savemail(e);
123 
124 	/*
125 	**  Instantiate or deinstantiate the queue.
126 	*/
127 
128 	if ((!queueit && !bitset(EF_KEEPQUEUE, e->e_flags)) ||
129 	    bitset(EF_CLRQUEUE, e->e_flags))
130 	{
131 		if (e->e_dfp != NULL)
132 			(void) fclose(e->e_dfp);
133 		if (e->e_df != NULL)
134 			xunlink(e->e_df);
135 		xunlink(queuename(e, 'q'));
136 	}
137 	else if (queueit || !bitset(EF_INQUEUE, e->e_flags))
138 		queueup(e, FALSE, FALSE);
139 
140 	/* now unlock the job */
141 	closexscript(e);
142 	unlockqueue(e);
143 
144 	/* make sure that this envelope is marked unused */
145 	e->e_id = e->e_df = NULL;
146 	e->e_dfp = NULL;
147 }
148 /*
149 **  CLEARENVELOPE -- clear an envelope without unlocking
150 **
151 **	This is normally used by a child process to get a clean
152 **	envelope without disturbing the parent.
153 **
154 **	Parameters:
155 **		e -- the envelope to clear.
156 **
157 **	Returns:
158 **		none.
159 **
160 **	Side Effects:
161 **		Closes files associated with the envelope.
162 **		Marks the envelope as unallocated.
163 */
164 
165 clearenvelope(e)
166 	register ENVELOPE *e;
167 {
168 	/* clear out any file information */
169 	if (e->e_xfp != NULL)
170 		(void) fclose(e->e_xfp);
171 	if (e->e_dfp != NULL)
172 		(void) fclose(e->e_dfp);
173 	e->e_xfp = e->e_dfp = NULL;
174 
175 	/* now expunge names of objects */
176 	e->e_df = e->e_id = NULL;
177 
178 	/* and the flags which are now meaningless */
179 	e->e_flags = 0;
180 }
181 /*
182 **  UNLOCKQUEUE -- unlock the queue entry for a specified envelope
183 **
184 **	Parameters:
185 **		e -- the envelope to unlock.
186 **
187 **	Returns:
188 **		none
189 **
190 **	Side Effects:
191 **		unlocks the queue for `e'.
192 */
193 
194 unlockqueue(e)
195 	ENVELOPE *e;
196 {
197 	/* remove the transcript */
198 #ifdef DEBUG
199 # ifdef LOG
200 	if (LogLevel > 19)
201 		syslog(LOG_DEBUG, "%s: unlock", e->e_id);
202 # endif LOG
203 	if (!tTd(51, 4))
204 #endif DEBUG
205 		xunlink(queuename(e, 'x'));
206 
207 	/* last but not least, remove the lock */
208 	xunlink(queuename(e, 'l'));
209 }
210 /*
211 **  INITSYS -- initialize instantiation of system
212 **
213 **	In Daemon mode, this is done in the child.
214 **
215 **	Parameters:
216 **		none.
217 **
218 **	Returns:
219 **		none.
220 **
221 **	Side Effects:
222 **		Initializes the system macros, some global variables,
223 **		etc.  In particular, the current time in various
224 **		forms is set.
225 */
226 
227 initsys()
228 {
229 	auto time_t now;
230 	static char cbuf[5];			/* holds hop count */
231 	static char dbuf[30];			/* holds ctime(tbuf) */
232 	static char pbuf[10];			/* holds pid */
233 	static char tbuf[20];			/* holds "current" time */
234 	static char ybuf[10];			/* holds tty id */
235 	register char *p;
236 	register struct tm *tm;
237 	extern char *ttyname();
238 	extern char *arpadate();
239 	extern struct tm *gmtime();
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(CurEnv);
249 	CurEnv->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 = CurEnv->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, CurEnv);
268 
269 	/* hop count */
270 	(void) sprintf(cbuf, "%d", CurEnv->e_hopcount);
271 	define('c', cbuf, CurEnv);
272 
273 	/* time as integer, unix time, arpa time */
274 	now = curtime();
275 	tm = gmtime(&now);
276 	(void) sprintf(tbuf, "%02d%02d%02d%02d%02d", tm->tm_year, tm->tm_mon,
277 			tm->tm_mday, tm->tm_hour, tm->tm_min);
278 	define('t', tbuf, CurEnv);
279 	(void) strcpy(dbuf, ctime(&now));
280 	*index(dbuf, '\n') = '\0';
281 	if (macvalue('d', CurEnv) == NULL)
282 		define('d', dbuf, CurEnv);
283 	p = newstr(arpadate(dbuf));
284 	if (macvalue('a', CurEnv) == NULL)
285 		define('a', p, CurEnv);
286 	define('b', p, CurEnv);
287 
288 	/* version */
289 	define('v', Version, CurEnv);
290 
291 	/* tty name */
292 	if (macvalue('y', CurEnv) == NULL)
293 	{
294 		p = ttyname(2);
295 		if (p != NULL)
296 		{
297 			if (rindex(p, '/') != NULL)
298 				p = rindex(p, '/') + 1;
299 			(void) strcpy(ybuf, p);
300 			define('y', ybuf, CurEnv);
301 		}
302 	}
303 }
304 /*
305 **  QUEUENAME -- build a file name in the queue directory for this envelope.
306 **
307 **	Assigns an id code if one does not already exist.
308 **	This code is very careful to avoid trashing existing files
309 **	under any circumstances.
310 **		We first create an nf file that is only used when
311 **		assigning an id.  This file is always empty, so that
312 **		we can never accidently truncate an lf file.
313 **
314 **	Parameters:
315 **		e -- envelope to build it in/from.
316 **		type -- the file type, used as the first character
317 **			of the file name.
318 **
319 **	Returns:
320 **		a pointer to the new file name (in a static buffer).
321 **
322 **	Side Effects:
323 **		Will create the lf and qf files if no id code is
324 **		already assigned.  This will cause the envelope
325 **		to be modified.
326 */
327 
328 char *
329 queuename(e, type)
330 	register ENVELOPE *e;
331 	char type;
332 {
333 	static char buf[MAXNAME];
334 	static int pid = -1;
335 	char c1 = 'A';
336 	char c2 = 'A';
337 
338 	if (e->e_id == NULL)
339 	{
340 		char qf[20];
341 		char lf[20];
342 		char nf[20];
343 
344 		/* find a unique id */
345 		if (pid != getpid())
346 		{
347 			/* new process -- start back at "AA" */
348 			pid = getpid();
349 			c1 = 'A';
350 			c2 = 'A' - 1;
351 		}
352 		(void) sprintf(qf, "qfAA%05d", pid);
353 		strcpy(lf, qf);
354 		lf[0] = 'l';
355 		strcpy(nf, qf);
356 		nf[0] = 'n';
357 
358 		while (c1 < '~' || c2 < 'Z')
359 		{
360 			int i;
361 
362 			if (c2 >= 'Z')
363 			{
364 				c1++;
365 				c2 = 'A' - 1;
366 			}
367 			qf[2] = lf[2] = nf[2] = c1;
368 			qf[3] = lf[3] = nf[3] = ++c2;
369 # ifdef DEBUG
370 			if (tTd(7, 20))
371 				printf("queuename: trying \"%s\"\n", nf);
372 # endif DEBUG
373 			if (access(lf, 0) >= 0 || access(qf, 0) >= 0)
374 				continue;
375 			errno = 0;
376 			i = creat(nf, FileMode);
377 			if (i < 0)
378 			{
379 				(void) unlink(nf);	/* kernel bug */
380 				continue;
381 			}
382 			(void) close(i);
383 			i = link(nf, lf);
384 			(void) unlink(nf);
385 			if (i < 0)
386 				continue;
387 			if (link(lf, qf) >= 0)
388 				break;
389 			(void) unlink(lf);
390 		}
391 		if (c1 >= '~' && c2 >= 'Z')
392 		{
393 			syserr("queuename: Cannot create \"%s\" in \"%s\"",
394 				lf, QueueDir);
395 			exit(EX_OSERR);
396 		}
397 		e->e_id = newstr(&qf[2]);
398 		define('i', e->e_id, e);
399 # ifdef DEBUG
400 		if (tTd(7, 1))
401 			printf("queuename: assigned id %s, env=%x\n", e->e_id, e);
402 # ifdef LOG
403 		if (LogLevel > 16)
404 			syslog(LOG_DEBUG, "%s: assigned id", e->e_id);
405 # endif LOG
406 # endif DEBUG
407 	}
408 
409 	if (type == '\0')
410 		return (NULL);
411 	(void) sprintf(buf, "%cf%s", type, e->e_id);
412 # ifdef DEBUG
413 	if (tTd(7, 2))
414 		printf("queuename: %s\n", buf);
415 # endif DEBUG
416 	return (buf);
417 }
418 /*
419 **  OPENXSCRIPT -- Open transcript file
420 **
421 **	Creates a transcript file for possible eventual mailing or
422 **	sending back.
423 **
424 **	Parameters:
425 **		e -- the envelope to create the transcript in/for.
426 **
427 **	Returns:
428 **		none
429 **
430 **	Side Effects:
431 **		Creates the transcript file.
432 */
433 
434 openxscript(e)
435 	register ENVELOPE *e;
436 {
437 	register char *p;
438 
439 # ifdef LOG
440 	if (LogLevel > 19)
441 		syslog(LOG_DEBUG, "%s: openx%s", e->e_id, e->e_xfp == NULL ? "" : " (no)");
442 # endif LOG
443 	if (e->e_xfp != NULL)
444 		return;
445 	p = queuename(e, 'x');
446 	e->e_xfp = fopen(p, "w");
447 	if (e->e_xfp == NULL)
448 		syserr("Can't create %s", p);
449 	else
450 		(void) chmod(p, 0644);
451 }
452 /*
453 **  CLOSEXSCRIPT -- close the transcript file.
454 **
455 **	Parameters:
456 **		e -- the envelope containing the transcript to close.
457 **
458 **	Returns:
459 **		none.
460 **
461 **	Side Effects:
462 **		none.
463 */
464 
465 closexscript(e)
466 	register ENVELOPE *e;
467 {
468 	if (e->e_xfp == NULL)
469 		return;
470 	(void) fclose(e->e_xfp);
471 	e->e_xfp = NULL;
472 }
473 /*
474 **  SETSENDER -- set the person who this message is from
475 **
476 **	Under certain circumstances allow the user to say who
477 **	s/he is (using -f or -r).  These are:
478 **	1.  The user's uid is zero (root).
479 **	2.  The user's login name is in an approved list (typically
480 **	    from a network server).
481 **	3.  The address the user is trying to claim has a
482 **	    "!" character in it (since #2 doesn't do it for
483 **	    us if we are dialing out for UUCP).
484 **	A better check to replace #3 would be if the
485 **	effective uid is "UUCP" -- this would require me
486 **	to rewrite getpwent to "grab" uucp as it went by,
487 **	make getname more nasty, do another passwd file
488 **	scan, or compile the UID of "UUCP" into the code,
489 **	all of which are reprehensible.
490 **
491 **	Assuming all of these fail, we figure out something
492 **	ourselves.
493 **
494 **	Parameters:
495 **		from -- the person we would like to believe this message
496 **			is from, as specified on the command line.
497 **
498 **	Returns:
499 **		none.
500 **
501 **	Side Effects:
502 **		sets sendmail's notion of who the from person is.
503 */
504 
505 setsender(from)
506 	char *from;
507 {
508 	register char **pvp;
509 	register struct passwd *pw = NULL;
510 	char *realname = NULL;
511 	char buf[MAXNAME];
512 	extern char *macvalue();
513 	extern char **prescan();
514 	extern bool safefile();
515 	extern char *FullName;
516 
517 # ifdef DEBUG
518 	if (tTd(45, 1))
519 		printf("setsender(%s)\n", from);
520 # endif DEBUG
521 
522 	/*
523 	**  Figure out the real user executing us.
524 	**	Username can return errno != 0 on non-errors.
525 	*/
526 
527 	if (QueueRun || OpMode == MD_SMTP || OpMode == MD_ARPAFTP)
528 		realname = from;
529 	if (realname == NULL || realname[0] == '\0')
530 	{
531 		extern char *username();
532 
533 		realname = username();
534 		errno = 0;
535 	}
536 	if (realname == NULL || realname[0] == '\0')
537 	{
538 		extern struct passwd *getpwuid();
539 
540 		pw = getpwuid(getruid());
541 		if (pw != NULL)
542 			realname = pw->pw_name;
543 	}
544 	if (realname == NULL || realname[0] == '\0')
545 	{
546 		syserr("Who are you?");
547 		realname = "root";
548 	}
549 
550 	/*
551 	**  Determine if this real person is allowed to alias themselves.
552 	*/
553 
554 	if (from != NULL)
555 	{
556 		extern bool trusteduser();
557 
558 		if (!trusteduser(realname) &&
559 # ifdef DEBUG
560 		    (!tTd(1, 9) || getuid() != geteuid()) &&
561 # endif DEBUG
562 		    index(from, '!') == NULL && getuid() != 0)
563 		{
564 			/* network sends -r regardless (why why why?) */
565 			/* syserr("%s, you cannot use the -f flag", realname); */
566 			from = NULL;
567 		}
568 	}
569 
570 	SuprErrs = TRUE;
571 	if (from == NULL || parseaddr(from, &CurEnv->e_from, 1) == NULL)
572 	{
573 		from = newstr(realname);
574 		(void) parseaddr(from, &CurEnv->e_from, 1);
575 	}
576 	else
577 		FromFlag = TRUE;
578 	CurEnv->e_from.q_flags |= QDONTSEND;
579 	SuprErrs = FALSE;
580 
581 	if (pw == NULL && CurEnv->e_from.q_mailer == LocalMailer)
582 	{
583 		extern struct passwd *getpwnam();
584 
585 		pw = getpwnam(CurEnv->e_from.q_user);
586 	}
587 
588 	/*
589 	**  Process passwd file entry.
590 	*/
591 
592 	if (pw != NULL)
593 	{
594 		/* extract home directory */
595 		CurEnv->e_from.q_home = newstr(pw->pw_dir);
596 
597 		/* run user's .mailcf file */
598 		define('z', CurEnv->e_from.q_home, CurEnv);
599 		expand("$z/.mailcf", buf, &buf[sizeof buf - 1], CurEnv);
600 		if (safefile(buf, getruid(), S_IREAD))
601 			readcf(buf, FALSE);
602 
603 		/* if the user has given fullname already, don't redefine */
604 		if (FullName == NULL)
605 			FullName = macvalue('x', CurEnv);
606 		if (FullName[0] == '\0')
607 			FullName = NULL;
608 
609 		/* extract full name from passwd file */
610 		if (FullName == NULL && pw->pw_gecos != NULL &&
611 		    strcmp(pw->pw_name, CurEnv->e_from.q_user) == 0)
612 		{
613 			buildfname(pw->pw_gecos, CurEnv->e_from.q_user, buf);
614 			if (buf[0] != '\0')
615 				FullName = newstr(buf);
616 		}
617 		if (FullName != NULL)
618 			define('x', FullName, CurEnv);
619 	}
620 
621 #ifndef V6
622 	if (CurEnv->e_from.q_home == NULL)
623 		CurEnv->e_from.q_home = getenv("HOME");
624 #endif V6
625 	CurEnv->e_from.q_uid = getuid();
626 	CurEnv->e_from.q_gid = getgid();
627 	if (CurEnv->e_from.q_uid != 0)
628 	{
629 		DefUid = CurEnv->e_from.q_uid;
630 		DefGid = CurEnv->e_from.q_gid;
631 	}
632 
633 	/*
634 	**  Rewrite the from person to dispose of possible implicit
635 	**	links in the net.
636 	*/
637 
638 	pvp = prescan(from, '\0');
639 	if (pvp == NULL)
640 	{
641 		syserr("cannot prescan from (%s)", from);
642 		finis();
643 	}
644 	rewrite(pvp, 3);
645 	rewrite(pvp, 1);
646 	cataddr(pvp, buf, sizeof buf);
647 	define('f', newstr(buf), CurEnv);
648 
649 	/* save the domain spec if this mailer wants it */
650 	if (bitset(M_CANONICAL, CurEnv->e_from.q_mailer->m_flags))
651 	{
652 		extern char **copyplist();
653 
654 		while (*pvp != NULL && strcmp(*pvp, "@") != 0)
655 			pvp++;
656 		if (*pvp != NULL)
657 			CurEnv->e_fromdomain = copyplist(pvp, TRUE);
658 	}
659 }
660 /*
661 **  TRUSTEDUSER -- tell us if this user is to be trusted.
662 **
663 **	Parameters:
664 **		user -- the user to be checked.
665 **
666 **	Returns:
667 **		TRUE if the user is in an approved list.
668 **		FALSE otherwise.
669 **
670 **	Side Effects:
671 **		none.
672 */
673 
674 bool
675 trusteduser(user)
676 	char *user;
677 {
678 	register char **ulist;
679 	extern char *TrustedUsers[];
680 
681 	for (ulist = TrustedUsers; *ulist != NULL; ulist++)
682 		if (strcmp(*ulist, user) == 0)
683 			return (TRUE);
684 	return (FALSE);
685 }
686