1 # include <stdio.h>
2 # include <pwd.h>
3 # include <signal.h>
4 # include "dlvrmail.h"
5 # ifdef LOG
6 # include <log.h>
7 # endif LOG
8 
9 static char SccsId[] = "@(#)deliver.c	2.5	02/05/81";
10 
11 /*
12 **  DELIVER -- Deliver a message to a particular address.
13 **
14 **	Algorithm:
15 **		Compute receiving network (i.e., mailer), host, & user.
16 **		If local, see if this is really a program name.
17 **		Build argument for the mailer.
18 **		Create pipe through edit fcn if appropriate.
19 **		Fork.
20 **			Child: call mailer
21 **		Parent: call editfcn if specified.
22 **		Wait for mailer to finish.
23 **		Interpret exit status.
24 **
25 **	Parameters:
26 **		to -- the address to deliver the message to.
27 **		editfcn -- if non-NULL, we want to call this function
28 **			to output the letter (instead of just out-
29 **			putting it raw).
30 **
31 **	Returns:
32 **		zero -- successfully delivered.
33 **		else -- some failure, see ExitStat for more info.
34 **
35 **	Side Effects:
36 **		The standard input is passed off to someone.
37 **
38 **	WARNING:
39 **		The standard input is shared amongst all children,
40 **		including the file pointer.  It is critical that the
41 **		parent waits for the child to finish before forking
42 **		another child.
43 **
44 **	Called By:
45 **		main
46 **		savemail
47 **
48 **	Files:
49 **		standard input -- must be opened to the message to
50 **			deliver.
51 */
52 
53 deliver(to, editfcn)
54 	addrq *to;
55 	int (*editfcn)();
56 {
57 	register struct mailer *m;
58 	char *host;
59 	char *user;
60 	extern struct passwd *getpwnam();
61 	char **pvp;
62 	extern char **buildargv();
63 	auto int st;
64 	register int i;
65 	register char *p;
66 	int pid;
67 	int pvect[2];
68 	extern FILE *fdopen();
69 	extern int errno;
70 	FILE *mfile;
71 	extern putheader();
72 	extern pipesig();
73 	extern bool GotHdr;
74 	extern char *index();
75 
76 	/*
77 	**  Compute receiving mailer, host, and to addreses.
78 	**	Do some initialization first.  To is the to address
79 	**	for error messages.
80 	*/
81 
82 	To = to->q_paddr;
83 	m = to->q_mailer;
84 	user = to->q_user;
85 	host = to->q_host;
86 	Errors = 0;
87 	errno = 0;
88 # ifdef DEBUG
89 	if (Debug)
90 		printf("deliver(%s [%d, `%s', `%s'])\n", To, m, host, user);
91 # endif DEBUG
92 
93 	/*
94 	**  Remove quote bits from user/host.
95 	*/
96 
97 	for (p = user; (*p++ &= 0177) != '\0'; )
98 		continue;
99 	if (host != NULL)
100 		for (p = host; (*p++ &= 0177) != '\0'; )
101 			continue;
102 
103 	/*
104 	**  Strip quote bits from names if the mailer wants it.
105 	*/
106 
107 	if (flagset(M_STRIPQ, m->m_flags))
108 	{
109 		stripquotes(user);
110 		stripquotes(host);
111 	}
112 
113 	/*
114 	**  See if this user name is "special".
115 	**	If the user is a program, diddle with the mailer spec.
116 	**	If the user name has a slash in it, assume that this
117 	**		is a file -- send it off without further ado.
118 	**		Note that this means that editfcn's will not
119 	**		be applied to the message.
120 	*/
121 
122 	if (m == &Mailer[0])
123 	{
124 		if (*user == '|')
125 		{
126 			user++;
127 			m = &Mailer[1];
128 		}
129 		else
130 		{
131 			if (index(user, '/') != NULL)
132 			{
133 				i = mailfile(user);
134 				giveresponse(i, TRUE, m);
135 				return (i);
136 			}
137 		}
138 	}
139 
140 	/*
141 	**  See if the user exists.
142 	**	Strictly, this is only needed to print a pretty
143 	**	error message.
144 	**
145 	**	>>>>>>>>>> This clause assumes that the local mailer
146 	**	>> NOTE >> cannot do any further aliasing; that
147 	**	>>>>>>>>>> function is subsumed by delivermail.
148 	*/
149 
150 	if (m == &Mailer[0])
151 	{
152 		if (getpwnam(user) == NULL)
153 		{
154 			giveresponse(EX_NOUSER, TRUE, m);
155 			return (EX_NOUSER);
156 		}
157 	}
158 
159 	/*
160 	**  If the mailer wants a From line, insert a new editfcn.
161 	*/
162 
163 	if (flagset(M_HDR, m->m_flags) && editfcn == NULL && (!GotHdr || flagset(M_FHDR, m->m_flags)))
164 		editfcn = putheader;
165 
166 	/*
167 	**  Call the mailer.
168 	**	The argument vector gets built, pipes through 'editfcn'
169 	**	are created as necessary, and we fork & exec as
170 	**	appropriate.  In the parent, we call 'editfcn'.
171 	*/
172 
173 	pvp = buildargv(m->m_argv, m->m_flags, host, user, From.q_paddr);
174 	if (pvp == NULL)
175 	{
176 		usrerr("name too long");
177 		return (-1);
178 	}
179 	rewind(stdin);
180 
181 	/* create a pipe if we will need one */
182 	if (editfcn != NULL && pipe(pvect) < 0)
183 	{
184 		syserr("pipe");
185 		return (-1);
186 	}
187 # ifdef VFORK
188 	pid = vfork();
189 # else
190 	pid = fork();
191 # endif
192 	if (pid < 0)
193 	{
194 		syserr("Cannot fork");
195 		if (editfcn != NULL)
196 		{
197 			close(pvect[0]);
198 			close(pvect[1]);
199 		}
200 		return (-1);
201 	}
202 	else if (pid == 0)
203 	{
204 		/* child -- set up input & exec mailer */
205 		/* make diagnostic output be standard output */
206 		close(2);
207 		dup(1);
208 		signal(SIGINT, SIG_IGN);
209 		if (editfcn != NULL)
210 		{
211 			close(0);
212 			if (dup(pvect[0]) < 0)
213 			{
214 				syserr("Cannot dup to zero!");
215 				_exit(EX_OSERR);
216 			}
217 			close(pvect[0]);
218 			close(pvect[1]);
219 		}
220 		if (!flagset(M_RESTR, m->m_flags))
221 			setuid(getuid());
222 # ifdef LOG
223 		closelog();
224 # endif LOG
225 # ifndef VFORK
226 		/*
227 		 * We have to be careful with vfork - we can't mung up the
228 		 * memory but we don't want the mailer to inherit any extra
229 		 * open files.  Chances are the mailer won't
230 		 * care about an extra file, but then again you never know.
231 		 * Actually, we would like to close(fileno(pwf)), but it's
232 		 * declared static so we can't.  But if we fclose(pwf), which
233 		 * is what endpwent does, it closes it in the parent too and
234 		 * the next getpwnam will be slower.  If you have a weird mailer
235 		 * that chokes on the extra file you should do the endpwent().
236 		 */
237 		endpwent();
238 # endif
239 		execv(m->m_mailer, pvp);
240 		/* syserr fails because log is closed */
241 		/* syserr("Cannot exec %s", m->m_mailer); */
242 		printf("Cannot exec %s\n", m->m_mailer);
243 		fflush(stdout);
244 		_exit(EX_UNAVAILABLE);
245 	}
246 
247 	/* arrange to write out header message if error */
248 	if (editfcn != NULL)
249 	{
250 		close(pvect[0]);
251 		signal(SIGPIPE, pipesig);
252 		mfile = fdopen(pvect[1], "w");
253 		(*editfcn)(mfile);
254 		fclose(mfile);
255 	}
256 
257 	/*
258 	**  Wait for child to die and report status.
259 	**	We should never get fatal errors (e.g., segmentation
260 	**	violation), so we report those specially.  For other
261 	**	errors, we choose a status message (into statmsg),
262 	**	and if it represents an error, we print it.
263 	*/
264 
265 	while ((i = wait(&st)) > 0 && i != pid)
266 		continue;
267 	if (i < 0)
268 	{
269 		syserr("wait");
270 		return (-1);
271 	}
272 	if ((st & 0377) != 0)
273 	{
274 		syserr("%s: stat %o", pvp[0], st);
275 		ExitStat = EX_UNAVAILABLE;
276 		return (-1);
277 	}
278 	i = (st >> 8) & 0377;
279 	giveresponse(i, TRUE, m);
280 	return (i);
281 }
282 /*
283 **  GIVERESPONSE -- Interpret an error response from a mailer
284 **
285 **	Parameters:
286 **		stat -- the status code from the mailer (high byte
287 **			only; core dumps must have been taken care of
288 **			already).
289 **		force -- if set, force an error message output, even
290 **			if the mailer seems to like to print its own
291 **			messages.
292 **		m -- the mailer descriptor for this mailer.
293 **
294 **	Returns:
295 **		none.
296 **
297 **	Side Effects:
298 **		Errors may be incremented.
299 **		ExitStat may be set.
300 **
301 **	Called By:
302 **		deliver
303 */
304 
305 giveresponse(stat, force, m)
306 	int stat;
307 	int force;
308 	register struct mailer *m;
309 {
310 	register char *statmsg;
311 	extern char *SysExMsg[];
312 	register int i;
313 	extern int N_SysEx;
314 	extern long MsgSize;
315 	char buf[30];
316 
317 	i = stat - EX__BASE;
318 	if (i < 0 || i > N_SysEx)
319 		statmsg = NULL;
320 	else
321 		statmsg = SysExMsg[i];
322 	if (stat == 0)
323 		statmsg = "ok";
324 	else
325 	{
326 		Errors++;
327 		if (statmsg == NULL && m->m_badstat != 0)
328 		{
329 			stat = m->m_badstat;
330 			i = stat - EX__BASE;
331 # ifdef DEBUG
332 			if (i < 0 || i >= N_SysEx)
333 				syserr("Bad m_badstat %d", stat);
334 			else
335 # endif DEBUG
336 			statmsg = SysExMsg[i];
337 		}
338 		if (statmsg == NULL)
339 			usrerr("unknown mailer response %d", stat);
340 		else if (force || !flagset(M_QUIET, m->m_flags))
341 			usrerr("%s", statmsg);
342 	}
343 
344 	/*
345 	**  Final cleanup.
346 	**	Log a record of the transaction.  Compute the new
347 	**	ExitStat -- if we already had an error, stick with
348 	**	that.
349 	*/
350 
351 	if (statmsg == NULL)
352 	{
353 		sprintf(buf, "error %d", stat);
354 		statmsg = buf;
355 	}
356 
357 # ifdef LOG
358 	logmsg(LOG_INFO, "%s->%s: %ld: %s", From.q_paddr, To, MsgSize, statmsg);
359 # endif LOG
360 	setstat(stat);
361 	return (stat);
362 }
363 /*
364 **  PUTHEADER -- insert the From header into some mail
365 **
366 **	For mailers such as 'msgs' that want the header inserted
367 **	into the mail, this edit filter inserts the From line and
368 **	then passes the rest of the message through.
369 **
370 **	Parameters:
371 **		fp -- the file pointer for the output.
372 **
373 **	Returns:
374 **		none
375 **
376 **	Side Effects:
377 **		Puts a "From" line in UNIX format, and then
378 **			outputs the rest of the message.
379 **
380 **	Called By:
381 **		deliver
382 */
383 
384 putheader(fp)
385 	register FILE *fp;
386 {
387 	char buf[MAXLINE + 1];
388 	long tim;
389 	extern char *ctime();
390 	register char *p;
391 	extern char *index();
392 
393 	/* output the header part */
394 	fgets(buf, sizeof buf, stdin);
395 	if (strncmp(buf, "From ", 5) != 0 || (p = index(&buf[5], ' ')) == NULL)
396 	{
397 		time(&tim);
398 		fprintf(fp, "From %s %s", From.q_paddr, ctime(&tim));
399 		fputs(buf, fp);
400 	}
401 	else
402 		fprintf(fp, "From %s %s", From.q_paddr, &p[1]);
403 
404 	/* output the body */
405 	while (!ferror(fp) && fgets(buf, sizeof buf, stdin) != NULL)
406 		fputs(buf, fp);
407 	if (ferror(fp))
408 	{
409 		syserr("putheader: write error");
410 		setstat(EX_IOERR);
411 	}
412 }
413 /*
414 **  PIPESIG -- Handle broken pipe signals
415 **
416 **	This just logs an error.
417 **
418 **	Parameters:
419 **		none
420 **
421 **	Returns:
422 **		none
423 **
424 **	Side Effects:
425 **		logs an error message.
426 */
427 
428 pipesig()
429 {
430 	syserr("Broken pipe");
431 	signal(SIGPIPE, SIG_IGN);
432 }
433 /*
434 **  SENDTO -- Designate a send list.
435 **
436 **	The parameter is a comma-separated list of people to send to.
437 **	This routine arranges to send to all of them.
438 **
439 **	Parameters:
440 **		list -- the send list.
441 **		copyf -- the copy flag; passed to parse.
442 **
443 **	Returns:
444 **		none
445 **
446 **	Side Effects:
447 **		none.
448 **
449 **	Called By:
450 **		main
451 **		alias
452 */
453 
454 sendto(list, copyf)
455 	char *list;
456 	int copyf;
457 {
458 	register char *p;
459 	register char *q;
460 	register char c;
461 	addrq *a;
462 	extern addrq *parse();
463 	bool more;
464 
465 	/* more keeps track of what the previous delimiter was */
466 	more = TRUE;
467 	for (p = list; more; )
468 	{
469 		/* find the end of this address */
470 		q = p;
471 		while ((c = *p++) != '\0' && c != ',' && c != '\n')
472 			continue;
473 		more = c != '\0';
474 		*--p = '\0';
475 		if (more)
476 			p++;
477 
478 		/* parse the address */
479 		if ((a = parse(q, (addrq *) NULL, copyf)) == NULL)
480 			continue;
481 
482 		/* arrange to send to this person */
483 		recipient(a, &SendQ);
484 	}
485 	To = NULL;
486 }
487 /*
488 **  RECIPIENT -- Designate a message recipient
489 **
490 **	Saves the named person for future mailing.
491 **
492 **	Designates a person as a recipient.  This routine
493 **	does the initial parsing, and checks to see if
494 **	this person has already received the mail.
495 **	It also supresses local network names and turns them into
496 **	local names.
497 **
498 **	Parameters:
499 **		a -- the (preparsed) address header for the recipient.
500 **		targetq -- the queue to add the name to.
501 **
502 **	Returns:
503 **		none.
504 **
505 **	Side Effects:
506 **		none.
507 **
508 **	Called By:
509 **		sendto
510 **		main
511 */
512 
513 recipient(a, targetq)
514 	register addrq *a;
515 	addrq *targetq;
516 {
517 	register addrq *q;
518 	register struct mailer *m;
519 	register char **pvp;
520 	extern char *xalloc();
521 	extern bool forward();
522 	extern int errno;
523 	extern bool sameaddr();
524 
525 	To = a->q_paddr;
526 	m = a->q_mailer;
527 	errno = 0;
528 # ifdef DEBUG
529 	if (Debug)
530 		printf("recipient(%s)\n", To);
531 # endif DEBUG
532 
533 	/*
534 	**  Look up this person in the recipient list.  If they
535 	**  are there already, return, otherwise continue.
536 	*/
537 
538 	if (!ForceMail)
539 	{
540 		for (q = &SendQ; (q = nxtinq(q)) != NULL; )
541 			if (sameaddr(q, a, FALSE))
542 			{
543 # ifdef DEBUG
544 				if (Debug)
545 					printf("(%s in SendQ)\n", a->q_paddr);
546 # endif DEBUG
547 				return;
548 			}
549 		for (q = &AliasQ; (q = nxtinq(q)) != NULL; )
550 			if (sameaddr(q, a, FALSE))
551 			{
552 # ifdef DEBUG
553 				if (Debug)
554 					printf("(%s in AliasQ)\n", a->q_paddr);
555 # endif DEBUG
556 				return;
557 			}
558 	}
559 
560 	/*
561 	**  See if the user wants hir mail forwarded.
562 	**	`Forward' must do the forwarding recursively.
563 	*/
564 
565 	if (m == &Mailer[0] && !NoAlias && targetq == &SendQ && forward(a))
566 		return;
567 
568 	/*
569 	**  Put the user onto the target queue.
570 	*/
571 
572 	if (targetq != NULL)
573 	{
574 		putonq(a, targetq);
575 	}
576 
577 	return;
578 }
579 /*
580 **  BUILDARGV -- Build an argument vector for a mail server.
581 **
582 **	Using a template defined in config.c, an argv is built.
583 **	The format of the template is already a vector.  The
584 **	items of this vector are copied, unless a dollar sign
585 **	is encountered.  In this case, the next character
586 **	specifies something else to copy in.  These can be
587 **		$f	The from address.
588 **		$h	The host.
589 **		$u	The user.
590 **		$c	The hop count.
591 **	The vector is built in a local buffer.  A pointer to
592 **	the static argv is returned.
593 **
594 **	Parameters:
595 **		tmplt -- a template for an argument vector.
596 **		flags -- the flags for this server.
597 **		host -- the host name to send to.
598 **		user -- the user name to send to.
599 **		from -- the person this mail is from.
600 **
601 **	Returns:
602 **		A pointer to an argv.
603 **
604 **	Side Effects:
605 **		none
606 **
607 **	WARNING:
608 **		Since the argv is staticly allocated, any subsequent
609 **		calls will clobber the old argv.
610 **
611 **	Called By:
612 **		deliver
613 */
614 
615 char **
616 buildargv(tmplt, flags, host, user, from)
617 	char **tmplt;
618 	int flags;
619 	char *host;
620 	char *user;
621 	char *from;
622 {
623 	register char *p;
624 	register char *q;
625 	static char *pv[MAXPV+1];
626 	char **pvp;
627 	char **mvp;
628 	static char buf[512];
629 	register char *bp;
630 	char pbuf[30];
631 
632 	/*
633 	**  Do initial argv setup.
634 	**	Insert the mailer name.  Notice that $x expansion is
635 	**	NOT done on the mailer name.  Then, if the mailer has
636 	**	a picky -f flag, we insert it as appropriate.  This
637 	**	code does not check for 'pv' overflow; this places a
638 	**	manifest lower limit of 4 for MAXPV.
639 	*/
640 
641 	pvp = pv;
642 	bp = buf;
643 
644 	*pvp++ = tmplt[0];
645 
646 	/* insert -f or -r flag as appropriate */
647 	if (flagset(M_FOPT|M_ROPT, flags) && FromFlag)
648 	{
649 		if (flagset(M_FOPT, flags))
650 			*pvp++ = "-f";
651 		else
652 			*pvp++ = "-r";
653 		*pvp++ = From.q_paddr;
654 	}
655 
656 	/*
657 	**  Build the rest of argv.
658 	**	For each prototype parameter, the prototype is
659 	**	scanned character at a time.  If a dollar-sign is
660 	**	found, 'q' is set to the appropriate expansion,
661 	**	otherwise it is null.  Then either the string
662 	**	pointed to by q, or the original character, is
663 	**	interpolated into the buffer.  Buffer overflow is
664 	**	checked.
665 	*/
666 
667 	for (mvp = tmplt; (p = *++mvp) != NULL; )
668 	{
669 		if (pvp >= &pv[MAXPV])
670 		{
671 			syserr("Too many parameters to %s", pv[0]);
672 			return (NULL);
673 		}
674 		*pvp++ = bp;
675 		for (; *p != '\0'; p++)
676 		{
677 			/* q will be the interpolated quantity */
678 			q = NULL;
679 			if (*p == '$')
680 			{
681 				switch (*++p)
682 				{
683 				  case 'f':	/* from person */
684 					q = from;
685 					break;
686 
687 				  case 'u':	/* user */
688 					q = user;
689 					break;
690 
691 				  case 'h':	/* host */
692 					q = host;
693 					break;
694 
695 				  case 'c':	/* hop count */
696 					sprintf(pbuf, "%d", HopCount);
697 					q = pbuf;
698 					break;
699 				}
700 			}
701 
702 			/*
703 			**  Interpolate q or output one character
704 			**	Strip quote bits as we proceed.....
705 			*/
706 
707 			if (q != NULL)
708 			{
709 				while (bp < &buf[sizeof buf - 1] && (*bp++ = *q++) != '\0')
710 					continue;
711 				bp--;
712 			}
713 			else if (bp < &buf[sizeof buf - 1])
714 				*bp++ = *p;
715 		}
716 		*bp++ = '\0';
717 		if (bp >= &buf[sizeof buf - 1])
718 			return (NULL);
719 	}
720 	*pvp = NULL;
721 
722 # ifdef DEBUG
723 	if (Debug)
724 	{
725 		printf("Interpolated argv is:\n");
726 		for (mvp = pv; *mvp != NULL; mvp++)
727 			printf("\t%s\n", *mvp);
728 	}
729 # endif DEBUG
730 
731 	return (pv);
732 }
733 /*
734 **  MAILFILE -- Send a message to a file.
735 **
736 **	Parameters:
737 **		filename -- the name of the file to send to.
738 **
739 **	Returns:
740 **		The exit code associated with the operation.
741 **
742 **	Side Effects:
743 **		none.
744 **
745 **	Called By:
746 **		deliver
747 */
748 
749 mailfile(filename)
750 	char *filename;
751 {
752 	char buf[MAXLINE];
753 	register FILE *f;
754 	auto long tim;
755 	extern char *ctime();
756 
757 	f = fopen(filename, "a");
758 	if (f == NULL)
759 		return (EX_CANTCREAT);
760 
761 	/* output the timestamp */
762 	time(&tim);
763 	fprintf(f, "From %s %s", From.q_paddr, ctime(&tim));
764 	rewind(stdin);
765 	while (fgets(buf, sizeof buf, stdin) != NULL)
766 	{
767 		fputs(buf, f);
768 		if (ferror(f))
769 		{
770 			fclose(f);
771 			return (EX_IOERR);
772 		}
773 	}
774 	fputs("\n", f);
775 	fclose(f);
776 	return (EX_OK);
777 }
778