1 # include <signal.h>
2 # include <errno.h>
3 # include "sendmail.h"
4 # ifdef LOG
5 # include <syslog.h>
6 # endif LOG
7 
8 static char SccsId[] = "@(#)deliver.c	3.34	09/06/81";
9 
10 /*
11 **  DELIVER -- Deliver a message to a particular address.
12 **
13 **	Parameters:
14 **		to -- the address to deliver the message to.
15 **		editfcn -- if non-NULL, we want to call this function
16 **			to output the letter (instead of just out-
17 **			putting it raw).
18 **
19 **	Returns:
20 **		zero -- successfully delivered.
21 **		else -- some failure, see ExitStat for more info.
22 **
23 **	Side Effects:
24 **		The standard input is passed off to someone.
25 */
26 
27 deliver(to, editfcn)
28 	ADDRESS *to;
29 	int (*editfcn)();
30 {
31 	char *host;
32 	char *user;
33 	char **pvp;
34 	register char **mvp;
35 	register char *p;
36 	register struct mailer *m;
37 	register int i;
38 	extern putmessage();
39 	extern bool checkcompat();
40 	char *pv[MAXPV+1];
41 	char tobuf[MAXLINE];
42 	char buf[MAXNAME];
43 	bool firstone;
44 
45 	if (!ForceMail && bitset(QDONTSEND, to->q_flags))
46 		return (0);
47 
48 # ifdef DEBUG
49 	if (Debug)
50 		printf("\n--deliver, mailer=%d, host=`%s', first user=`%s'\n",
51 			to->q_mailer, to->q_host, to->q_user);
52 # endif DEBUG
53 
54 	/*
55 	**  Do initial argv setup.
56 	**	Insert the mailer name.  Notice that $x expansion is
57 	**	NOT done on the mailer name.  Then, if the mailer has
58 	**	a picky -f flag, we insert it as appropriate.  This
59 	**	code does not check for 'pv' overflow; this places a
60 	**	manifest lower limit of 4 for MAXPV.
61 	*/
62 
63 	m = Mailer[to->q_mailer];
64 	host = to->q_host;
65 	define('g', m->m_from);		/* translated from address */
66 	define('h', host);		/* to host */
67 	Errors = 0;
68 	errno = 0;
69 	pvp = pv;
70 	*pvp++ = m->m_argv[0];
71 
72 	/* insert -f or -r flag as appropriate */
73 	if (bitset(M_FOPT|M_ROPT, m->m_flags) && FromFlag)
74 	{
75 		if (bitset(M_FOPT, m->m_flags))
76 			*pvp++ = "-f";
77 		else
78 			*pvp++ = "-r";
79 		(void) expand("$g", buf, &buf[sizeof buf - 1]);
80 		*pvp++ = newstr(buf);
81 	}
82 
83 	/*
84 	**  Append the other fixed parts of the argv.  These run
85 	**  up to the first entry containing "$u".  There can only
86 	**  be one of these, and there are only a few more slots
87 	**  in the pv after it.
88 	*/
89 
90 	for (mvp = m->m_argv; (p = *++mvp) != NULL; )
91 	{
92 		while ((p = index(p, '$')) != NULL)
93 			if (*++p == 'u')
94 				break;
95 		if (p != NULL)
96 			break;
97 
98 		/* this entry is safe -- go ahead and process it */
99 		(void) expand(*mvp, buf, &buf[sizeof buf - 1]);
100 		*pvp++ = newstr(buf);
101 		if (pvp >= &pv[MAXPV - 3])
102 		{
103 			syserr("Too many parameters to %s before $u", pv[0]);
104 			return (-1);
105 		}
106 	}
107 	if (*mvp == NULL)
108 		syserr("No $u in mailer argv for %s", pv[0]);
109 
110 	/*
111 	**  At this point *mvp points to the argument with $u.  We
112 	**  run through our address list and append all the addresses
113 	**  we can.  If we run out of space, do not fret!  We can
114 	**  always send another copy later.
115 	*/
116 
117 	tobuf[0] = '\0';
118 	firstone = TRUE;
119 	To = tobuf;
120 	for (; to != NULL; to = to->q_next)
121 	{
122 		/* avoid sending multiple recipients to dumb mailers */
123 		if (!firstone && !bitset(M_MUSER, m->m_flags))
124 			break;
125 
126 		/* if already sent or not for this host, don't send */
127 		if ((!ForceMail && bitset(QDONTSEND, to->q_flags)) ||
128 		    strcmp(to->q_host, host) != 0)
129 			continue;
130 		user = to->q_user;
131 		To = to->q_paddr;
132 		to->q_flags |= QDONTSEND;
133 		firstone = FALSE;
134 
135 # ifdef DEBUG
136 		if (Debug)
137 			printf("   send to `%s'\n", user);
138 # endif DEBUG
139 
140 		/*
141 		**  Check to see that these people are allowed to
142 		**  talk to each other.
143 		*/
144 
145 		if (!checkcompat(to))
146 		{
147 			giveresponse(EX_UNAVAILABLE, TRUE, m);
148 			continue;
149 		}
150 
151 		/*
152 		**  Strip quote bits from names if the mailer is dumb
153 		**	about them.
154 		*/
155 
156 		if (bitset(M_STRIPQ, m->m_flags))
157 		{
158 			stripquotes(user, TRUE);
159 			stripquotes(host, TRUE);
160 		}
161 		else
162 		{
163 			stripquotes(user, FALSE);
164 			stripquotes(host, FALSE);
165 		}
166 
167 		/*
168 		**  If an error message has already been given, don't
169 		**	bother to send to this address.
170 		**
171 		**	>>>>>>>>>> This clause assumes that the local mailer
172 		**	>> NOTE >> cannot do any further aliasing; that
173 		**	>>>>>>>>>> function is subsumed by sendmail.
174 		*/
175 
176 		if (bitset(QBADADDR, to->q_flags))
177 			continue;
178 
179 		/* save statistics.... */
180 		Stat.stat_nt[to->q_mailer]++;
181 		Stat.stat_bt[to->q_mailer] += kbytes(MsgSize);
182 
183 		/*
184 		**  See if this user name is "special".
185 		**	If the user name has a slash in it, assume that this
186 		**	is a file -- send it off without further ado.
187 		**	Note that this means that editfcn's will not
188 		**	be applied to the message.  Also note that
189 		**	this type of addresses is not processed along
190 		**	with the others, so we fudge on the To person.
191 		*/
192 
193 		if (m == Mailer[MN_LOCAL])
194 		{
195 			if (index(user, '/') != NULL)
196 			{
197 				i = mailfile(user);
198 				giveresponse(i, TRUE, m);
199 				continue;
200 			}
201 		}
202 
203 		/* create list of users for error messages */
204 		if (tobuf[0] != '\0')
205 			(void) strcat(tobuf, ",");
206 		(void) strcat(tobuf, to->q_paddr);
207 		define('u', user);		/* to user */
208 		define('z', to->q_home);	/* user's home */
209 
210 		/* expand out this user */
211 		(void) expand(*mvp, buf, &buf[sizeof buf - 1]);
212 		*pvp++ = newstr(buf);
213 		if (pvp >= &pv[MAXPV - 2])
214 		{
215 			/* allow some space for trailing parms */
216 			break;
217 		}
218 	}
219 
220 	/* see if any addresses still exist */
221 	if (tobuf[0] == '\0')
222 		return (0);
223 
224 	/* print out messages as full list */
225 	To = tobuf;
226 
227 	/*
228 	**  Fill out any parameters after the $u parameter.
229 	*/
230 
231 	while (*++mvp != NULL)
232 	{
233 		(void) expand(*mvp, buf, &buf[sizeof buf - 1]);
234 		*pvp++ = newstr(buf);
235 		if (pvp >= &pv[MAXPV])
236 			syserr("deliver: pv overflow after $u for %s", pv[0]);
237 	}
238 	*pvp++ = NULL;
239 
240 	/*
241 	**  Call the mailer.
242 	**	The argument vector gets built, pipes
243 	**	are created as necessary, and we fork & exec as
244 	**	appropriate.
245 	**
246 	**	Notice the tacky hack to handle private mailers.
247 	*/
248 
249 	if (editfcn == NULL)
250 		editfcn = putmessage;
251 	i = sendoff(m, pv, editfcn);
252 
253 	return (i);
254 }
255 /*
256 **  DOFORK -- do a fork, retrying a couple of times on failure.
257 **
258 **	This MUST be a macro, since after a vfork we are running
259 **	two processes on the same stack!!!
260 **
261 **	Parameters:
262 **		none.
263 **
264 **	Returns:
265 **		From a macro???  You've got to be kidding!
266 **
267 **	Side Effects:
268 **		Modifies the ==> LOCAL <== variable 'pid', leaving:
269 **			pid of child in parent, zero in child.
270 **			-1 on unrecoverable error.
271 **
272 **	Notes:
273 **		I'm awfully sorry this looks so awful.  That's
274 **		vfork for you.....
275 */
276 
277 # define NFORKTRIES	5
278 # ifdef VFORK
279 # define XFORK	vfork
280 # else VFORK
281 # define XFORK	fork
282 # endif VFORK
283 
284 # define DOFORK(fORKfN) \
285 {\
286 	register int i;\
287 \
288 	for (i = NFORKTRIES; i-- > 0; )\
289 	{\
290 		pid = fORKfN();\
291 		if (pid >= 0)\
292 			break;\
293 		sleep((unsigned) NFORKTRIES - i);\
294 	}\
295 }
296 /*
297 **  SENDOFF -- send off call to mailer & collect response.
298 **
299 **	Parameters:
300 **		m -- mailer descriptor.
301 **		pvp -- parameter vector to send to it.
302 **		editfcn -- function to pipe it through.
303 **
304 **	Returns:
305 **		exit status of mailer.
306 **
307 **	Side Effects:
308 **		none.
309 */
310 
311 sendoff(m, pvp, editfcn)
312 	struct mailer *m;
313 	char **pvp;
314 	int (*editfcn)();
315 {
316 	auto int st;
317 	register int i;
318 	int pid;
319 	int pvect[2];
320 	FILE *mfile;
321 	extern putmessage();
322 	extern FILE *fdopen();
323 
324 # ifdef DEBUG
325 	if (Debug)
326 	{
327 		printf("Sendoff:\n");
328 		printav(pvp);
329 	}
330 # endif DEBUG
331 
332 	/* create a pipe to shove the mail through */
333 	if (pipe(pvect) < 0)
334 	{
335 		syserr("pipe");
336 		return (-1);
337 	}
338 	DOFORK(XFORK);
339 	if (pid < 0)
340 	{
341 		syserr("Cannot fork");
342 		(void) close(pvect[0]);
343 		(void) close(pvect[1]);
344 		return (-1);
345 	}
346 	else if (pid == 0)
347 	{
348 		/* child -- set up input & exec mailer */
349 		/* make diagnostic output be standard output */
350 		(void) signal(SIGINT, SIG_DFL);
351 		(void) signal(SIGHUP, SIG_DFL);
352 		(void) signal(SIGTERM, SIG_DFL);
353 		(void) close(2);
354 		(void) dup(1);
355 		(void) close(0);
356 		if (dup(pvect[0]) < 0)
357 		{
358 			syserr("Cannot dup to zero!");
359 			_exit(EX_OSERR);
360 		}
361 		(void) close(pvect[0]);
362 		(void) close(pvect[1]);
363 		if (!bitset(M_RESTR, m->m_flags))
364 		{
365 			(void) setuid(getuid());
366 			(void) setgid(getgid());
367 		}
368 # ifndef VFORK
369 		/*
370 		**  We have to be careful with vfork - we can't mung up the
371 		**  memory but we don't want the mailer to inherit any extra
372 		**  open files.  Chances are the mailer won't
373 		**  care about an extra file, but then again you never know.
374 		**  Actually, we would like to close(fileno(pwf)), but it's
375 		**  declared static so we can't.  But if we fclose(pwf), which
376 		**  is what endpwent does, it closes it in the parent too and
377 		**  the next getpwnam will be slower.  If you have a weird
378 		**  mailer that chokes on the extra file you should do the
379 		**  endpwent().
380 		**
381 		**  Similar comments apply to log.  However, openlog is
382 		**  clever enough to set the FIOCLEX mode on the file,
383 		**  so it will be closed automatically on the exec.
384 		*/
385 
386 		endpwent();
387 # ifdef LOG
388 		closelog();
389 # endif LOG
390 # endif VFORK
391 		execv(m->m_mailer, pvp);
392 		/* syserr fails because log is closed */
393 		/* syserr("Cannot exec %s", m->m_mailer); */
394 		printf("Cannot exec '%s' errno=%d\n", m->m_mailer, errno);
395 		(void) fflush(stdout);
396 		_exit(EX_UNAVAILABLE);
397 	}
398 
399 	/* write out message to mailer */
400 	(void) close(pvect[0]);
401 	(void) signal(SIGPIPE, SIG_IGN);
402 	mfile = fdopen(pvect[1], "w");
403 	if (editfcn == NULL)
404 		editfcn = putmessage;
405 	(*editfcn)(mfile, m);
406 	(void) fclose(mfile);
407 
408 	/*
409 	**  Wait for child to die and report status.
410 	**	We should never get fatal errors (e.g., segmentation
411 	**	violation), so we report those specially.  For other
412 	**	errors, we choose a status message (into statmsg),
413 	**	and if it represents an error, we print it.
414 	*/
415 
416 	while ((i = wait(&st)) > 0 && i != pid)
417 		continue;
418 	if (i < 0)
419 	{
420 		syserr("wait");
421 		return (-1);
422 	}
423 	if ((st & 0377) != 0)
424 	{
425 		syserr("%s: stat %o", pvp[0], st);
426 		ExitStat = EX_UNAVAILABLE;
427 		return (-1);
428 	}
429 	i = (st >> 8) & 0377;
430 	giveresponse(i, TRUE, m);
431 	return (i);
432 }
433 /*
434 **  GIVERESPONSE -- Interpret an error response from a mailer
435 **
436 **	Parameters:
437 **		stat -- the status code from the mailer (high byte
438 **			only; core dumps must have been taken care of
439 **			already).
440 **		force -- if set, force an error message output, even
441 **			if the mailer seems to like to print its own
442 **			messages.
443 **		m -- the mailer descriptor for this mailer.
444 **
445 **	Returns:
446 **		none.
447 **
448 **	Side Effects:
449 **		Errors may be incremented.
450 **		ExitStat may be set.
451 **
452 **	Called By:
453 **		deliver
454 */
455 
456 giveresponse(stat, force, m)
457 	int stat;
458 	int force;
459 	register struct mailer *m;
460 {
461 	register char *statmsg;
462 	extern char *SysExMsg[];
463 	register int i;
464 	extern int N_SysEx;
465 	char buf[30];
466 
467 	i = stat - EX__BASE;
468 	if (i < 0 || i > N_SysEx)
469 		statmsg = NULL;
470 	else
471 		statmsg = SysExMsg[i];
472 	if (stat == 0)
473 	{
474 		if (bitset(M_LOCAL, m->m_flags))
475 			statmsg = "delivered";
476 		else
477 			statmsg = "queued";
478 		if (Verbose)
479 			message(Arpa_Info, statmsg);
480 	}
481 	else
482 	{
483 		Errors++;
484 		if (statmsg == NULL && m->m_badstat != 0)
485 		{
486 			stat = m->m_badstat;
487 			i = stat - EX__BASE;
488 # ifdef DEBUG
489 			if (i < 0 || i >= N_SysEx)
490 				syserr("Bad m_badstat %d", stat);
491 			else
492 # endif DEBUG
493 			statmsg = SysExMsg[i];
494 		}
495 		if (statmsg == NULL)
496 			usrerr("unknown mailer response %d", stat);
497 		else if (force || !bitset(M_QUIET, m->m_flags) || Verbose)
498 			usrerr("%s", statmsg);
499 	}
500 
501 	/*
502 	**  Final cleanup.
503 	**	Log a record of the transaction.  Compute the new
504 	**	ExitStat -- if we already had an error, stick with
505 	**	that.
506 	*/
507 
508 	if (statmsg == NULL)
509 	{
510 		(void) sprintf(buf, "error %d", stat);
511 		statmsg = buf;
512 	}
513 
514 # ifdef LOG
515 	syslog(LOG_INFO, "%s->%s: %ld: %s", From.q_paddr, To, MsgSize, statmsg);
516 # endif LOG
517 	setstat(stat);
518 }
519 /*
520 **  PUTMESSAGE -- output a message to the final mailer.
521 **
522 **	This routine takes care of recreating the header from the
523 **	in-core copy, etc.
524 **
525 **	Parameters:
526 **		fp -- file to output onto.
527 **		m -- a mailer descriptor.
528 **
529 **	Returns:
530 **		none.
531 **
532 **	Side Effects:
533 **		The message is written onto fp.
534 */
535 
536 putmessage(fp, m)
537 	FILE *fp;
538 	struct mailer *m;
539 {
540 	char buf[BUFSIZ];
541 	register int i;
542 	HDR *h;
543 	register char *p;
544 	extern char *arpadate();
545 	bool anyheader = FALSE;
546 	extern char *capitalize();
547 
548 	/* output "From" line unless supressed */
549 	if (!bitset(M_NHDR, m->m_flags))
550 	{
551 		(void) expand("$l", buf, &buf[sizeof buf - 1]);
552 		fprintf(fp, "%s\n", buf);
553 	}
554 
555 	/* output all header lines */
556 	for (h = Header; h != NULL; h = h->h_link)
557 	{
558 		if (bitset(H_CHECK|H_ACHECK, h->h_flags) && !bitset(h->h_mflags, m->m_flags))
559 		{
560 			p = ")><(";		/* can't happen (I hope) */
561 			goto checkfrom;
562 		}
563 		if (bitset(H_DEFAULT, h->h_flags))
564 		{
565 			(void) expand(h->h_value, buf, &buf[sizeof buf]);
566 			p = buf;
567 		}
568 		else
569 			p = h->h_value;
570 		if (*p == '\0')
571 			continue;
572 		fprintf(fp, "%s: %s\n", capitalize(h->h_field), p);
573 		h->h_flags |= H_USED;
574 		anyheader = TRUE;
575 
576 		/* hack, hack -- output Original-From field if different */
577 	checkfrom:
578 		if (strcmp(h->h_field, "from") == 0)
579 		{
580 			extern char *hvalue();
581 			char *ofrom = hvalue("original-from");
582 
583 			if (ofrom != NULL && strcmp(p, ofrom) != 0)
584 				fprintf(fp, "Original-From: %s\n", ofrom);
585 		}
586 	}
587 
588 	if (anyheader)
589 		fprintf(fp, "\n");
590 
591 	/* output the body of the message */
592 	rewind(TempFile);
593 	while (!ferror(fp) && (i = fread(buf, 1, BUFSIZ, TempFile)) > 0)
594 		(void) fwrite(buf, 1, i, fp);
595 
596 	if (ferror(fp) && errno != EPIPE)
597 	{
598 		syserr("putmessage: write error");
599 		setstat(EX_IOERR);
600 	}
601 	errno = 0;
602 }
603 /*
604 **  MAILFILE -- Send a message to a file.
605 **
606 **	Parameters:
607 **		filename -- the name of the file to send to.
608 **
609 **	Returns:
610 **		The exit code associated with the operation.
611 **
612 **	Side Effects:
613 **		none.
614 */
615 
616 mailfile(filename)
617 	char *filename;
618 {
619 	register FILE *f;
620 	register int pid;
621 	register int i;
622 
623 	/*
624 	**  Fork so we can change permissions here.
625 	**	Note that we MUST use fork, not vfork, because of
626 	**	the complications of calling subroutines, etc.
627 	*/
628 
629 	DOFORK(fork);
630 
631 	if (pid < 0)
632 		return (EX_OSERR);
633 	else if (pid == 0)
634 	{
635 		/* child -- actually write to file */
636 		(void) setuid(getuid());
637 		(void) setgid(getgid());
638 		(void) signal(SIGINT, SIG_DFL);
639 		(void) signal(SIGHUP, SIG_DFL);
640 		(void) signal(SIGTERM, SIG_DFL);
641 		f = fopen(filename, "a");
642 		if (f == NULL)
643 			exit(EX_CANTCREAT);
644 
645 		putmessage(f, Mailer[1]);
646 		fputs("\n", f);
647 		(void) fclose(f);
648 		(void) fflush(stdout);
649 		exit(EX_OK);
650 	}
651 	else
652 	{
653 		/* parent -- wait for exit status */
654 		register int i;
655 		auto int stat;
656 
657 		while ((i = wait(&stat)) != pid)
658 		{
659 			if (i < 0)
660 			{
661 				stat = EX_OSERR << 8;
662 				break;
663 			}
664 		}
665 		if ((stat & 0377) != 0)
666 			stat = EX_UNAVAILABLE << 8;
667 		return ((stat >> 8) & 0377);
668 	}
669 }
670