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 # include "sendmail.h"
10 
11 #ifndef lint
12 #ifdef SMTP
13 static char sccsid[] = "@(#)srvrsmtp.c	6.56 (Berkeley) 05/27/93 (with SMTP)";
14 #else
15 static char sccsid[] = "@(#)srvrsmtp.c	6.56 (Berkeley) 05/27/93 (without SMTP)";
16 #endif
17 #endif /* not lint */
18 
19 # include <errno.h>
20 # include <signal.h>
21 
22 # ifdef SMTP
23 
24 /*
25 **  SMTP -- run the SMTP protocol.
26 **
27 **	Parameters:
28 **		none.
29 **
30 **	Returns:
31 **		never.
32 **
33 **	Side Effects:
34 **		Reads commands from the input channel and processes
35 **			them.
36 */
37 
38 struct cmd
39 {
40 	char	*cmdname;	/* command name */
41 	int	cmdcode;	/* internal code, see below */
42 };
43 
44 /* values for cmdcode */
45 # define CMDERROR	0	/* bad command */
46 # define CMDMAIL	1	/* mail -- designate sender */
47 # define CMDRCPT	2	/* rcpt -- designate recipient */
48 # define CMDDATA	3	/* data -- send message text */
49 # define CMDRSET	4	/* rset -- reset state */
50 # define CMDVRFY	5	/* vrfy -- verify address */
51 # define CMDEXPN	6	/* expn -- expand address */
52 # define CMDNOOP	7	/* noop -- do nothing */
53 # define CMDQUIT	8	/* quit -- close connection and die */
54 # define CMDHELO	9	/* helo -- be polite */
55 # define CMDHELP	10	/* help -- give usage info */
56 # define CMDEHLO	11	/* ehlo -- extended helo (RFC 1425) */
57 /* non-standard commands */
58 # define CMDONEX	16	/* onex -- sending one transaction only */
59 # define CMDVERB	17	/* verb -- go into verbose mode */
60 /* debugging-only commands, only enabled if SMTPDEBUG is defined */
61 # define CMDDBGQSHOW	24	/* showq -- show send queue */
62 # define CMDDBGDEBUG	25	/* debug -- set debug mode */
63 
64 static struct cmd	CmdTab[] =
65 {
66 	"mail",		CMDMAIL,
67 	"rcpt",		CMDRCPT,
68 	"data",		CMDDATA,
69 	"rset",		CMDRSET,
70 	"vrfy",		CMDVRFY,
71 	"expn",		CMDEXPN,
72 	"help",		CMDHELP,
73 	"noop",		CMDNOOP,
74 	"quit",		CMDQUIT,
75 	"helo",		CMDHELO,
76 	"ehlo",		CMDEHLO,
77 	"verb",		CMDVERB,
78 	"onex",		CMDONEX,
79 	/*
80 	 * remaining commands are here only
81 	 * to trap and log attempts to use them
82 	 */
83 	"showq",	CMDDBGQSHOW,
84 	"debug",	CMDDBGDEBUG,
85 	NULL,		CMDERROR,
86 };
87 
88 bool	InChild = FALSE;		/* true if running in a subprocess */
89 bool	OneXact = FALSE;		/* one xaction only this run */
90 
91 #define EX_QUIT		22		/* special code for QUIT command */
92 
93 smtp(e)
94 	register ENVELOPE *e;
95 {
96 	register char *p;
97 	register struct cmd *c;
98 	char *cmd;
99 	static char *skipword();
100 	auto ADDRESS *vrfyqueue;
101 	ADDRESS *a;
102 	bool gotmail;			/* mail command received */
103 	bool gothello;			/* helo command received */
104 	bool vrfy;			/* set if this is a vrfy command */
105 	char *protocol;			/* sending protocol */
106 	char *sendinghost;		/* sending hostname */
107 	long msize;			/* approximate maximum message size */
108 	auto char *delimptr;
109 	char *id;
110 	int nrcpts;			/* number of RCPT commands */
111 	char inp[MAXLINE];
112 	char cmdbuf[MAXLINE];
113 	extern char Version[];
114 	extern ENVELOPE BlankEnvelope;
115 
116 	if (fileno(OutChannel) != fileno(stdout))
117 	{
118 		/* arrange for debugging output to go to remote host */
119 		(void) dup2(fileno(OutChannel), fileno(stdout));
120 	}
121 	settime(e);
122 	CurHostName = RealHostName;
123 	setproctitle("srvrsmtp %s startup", CurHostName);
124 	expand("\201e", inp, &inp[sizeof inp], e);
125 	message("220-%s", inp);
126 	message("220 ESMTP spoken here");
127 	protocol = NULL;
128 	sendinghost = macvalue('s', e);
129 	gothello = FALSE;
130 	gotmail = FALSE;
131 	for (;;)
132 	{
133 		/* arrange for backout */
134 		if (setjmp(TopFrame) > 0 && InChild)
135 		{
136 			QuickAbort = FALSE;
137 			SuprErrs = TRUE;
138 			finis();
139 		}
140 		QuickAbort = FALSE;
141 		HoldErrs = FALSE;
142 		LogUsrErrs = FALSE;
143 		e->e_flags &= ~EF_VRFYONLY;
144 
145 		/* setup for the read */
146 		e->e_to = NULL;
147 		Errors = 0;
148 		(void) fflush(stdout);
149 
150 		/* read the input line */
151 		SmtpPhase = "srvrsmtp cmd read";
152 		setproctitle("srvrsmtp %s cmd read", CurHostName);
153 		p = sfgets(inp, sizeof inp, InChannel, TimeOuts.to_nextcommand);
154 
155 		/* handle errors */
156 		if (p == NULL)
157 		{
158 			/* end of file, just die */
159 			message("421 %s Lost input channel from %s",
160 				MyHostName, CurHostName);
161 #ifdef LOG
162 			if (LogLevel > 1)
163 				syslog(LOG_NOTICE, "lost input channel from %s",
164 					CurHostName);
165 #endif
166 			if (InChild)
167 				ExitStat = EX_QUIT;
168 			finis();
169 		}
170 
171 		/* clean up end of line */
172 		fixcrlf(inp, TRUE);
173 
174 		/* echo command to transcript */
175 		if (e->e_xfp != NULL)
176 			fprintf(e->e_xfp, "<<< %s\n", inp);
177 
178 		if (e->e_id == NULL)
179 			setproctitle("%s: %s", CurHostName, inp);
180 		else
181 			setproctitle("%s %s: %s", e->e_id, CurHostName, inp);
182 
183 		/* break off command */
184 		for (p = inp; isascii(*p) && isspace(*p); p++)
185 			continue;
186 		cmd = cmdbuf;
187 		while (*p != '\0' &&
188 		       !(isascii(*p) && isspace(*p)) &&
189 		       cmd < &cmdbuf[sizeof cmdbuf - 2])
190 			*cmd++ = *p++;
191 		*cmd = '\0';
192 
193 		/* throw away leading whitespace */
194 		while (isascii(*p) && isspace(*p))
195 			p++;
196 
197 		/* decode command */
198 		for (c = CmdTab; c->cmdname != NULL; c++)
199 		{
200 			if (!strcasecmp(c->cmdname, cmdbuf))
201 				break;
202 		}
203 
204 		/* reset errors */
205 		errno = 0;
206 
207 		/* process command */
208 		switch (c->cmdcode)
209 		{
210 		  case CMDHELO:		/* hello -- introduce yourself */
211 		  case CMDEHLO:		/* extended hello */
212 			if (c->cmdcode == CMDEHLO)
213 			{
214 				protocol = "ESMTP";
215 				SmtpPhase = "EHLO";
216 			}
217 			else
218 			{
219 				protocol = "SMTP";
220 				SmtpPhase = "HELO";
221 			}
222 			sendinghost = newstr(p);
223 			if (strcasecmp(p, RealHostName) != 0)
224 			{
225 				auth_warning(e, "Host %s claimed to be %s",
226 					RealHostName, p);
227 			}
228 			p = macvalue('_', e);
229 			if (p == NULL)
230 				p = RealHostName;
231 
232 			gothello = TRUE;
233 			if (c->cmdcode != CMDEHLO)
234 			{
235 				/* print old message and be done with it */
236 				message("250 %s Hello %s, pleased to meet you",
237 					MyHostName, p);
238 				break;
239 			}
240 
241 			/* print extended message and brag */
242 			message("250-%s Hello %s, pleased to meet you",
243 				MyHostName, p);
244 			if (!bitset(PRIV_NOEXPN, PrivacyFlags))
245 				message("250-EXPN");
246 			if (MaxMessageSize > 0)
247 				message("250-SIZE %ld", MaxMessageSize);
248 			else
249 				message("250-SIZE");
250 			message("250 HELP");
251 			break;
252 
253 		  case CMDMAIL:		/* mail -- designate sender */
254 			SmtpPhase = "MAIL";
255 
256 			/* check for validity of this command */
257 			if (!gothello)
258 			{
259 				/* set sending host to our known value */
260 				if (sendinghost == NULL)
261 					sendinghost = RealHostName;
262 
263 				if (bitset(PRIV_NEEDMAILHELO, PrivacyFlags))
264 				{
265 					message("503 Polite people say HELO first");
266 					break;
267 				}
268 				else
269 				{
270 					auth_warning(e,
271 						"Host %s didn't use HELO protocol",
272 						RealHostName);
273 				}
274 			}
275 			if (gotmail)
276 			{
277 				message("503 Sender already specified");
278 				break;
279 			}
280 			if (InChild)
281 			{
282 				errno = 0;
283 				syserr("503 Nested MAIL command: MAIL %s", p);
284 				finis();
285 			}
286 
287 			/* fork a subprocess to process this command */
288 			if (runinchild("SMTP-MAIL", e) > 0)
289 				break;
290 			if (protocol == NULL)
291 				protocol = "SMTP";
292 			define('r', protocol, e);
293 			define('s', sendinghost, e);
294 			initsys(e);
295 			nrcpts = 0;
296 			setproctitle("%s %s: %s", e->e_id, CurHostName, inp);
297 
298 			/* child -- go do the processing */
299 			p = skipword(p, "from");
300 			if (p == NULL)
301 				break;
302 			if (setjmp(TopFrame) > 0)
303 			{
304 				/* this failed -- undo work */
305 				if (InChild)
306 				{
307 					QuickAbort = FALSE;
308 					SuprErrs = TRUE;
309 					finis();
310 				}
311 				break;
312 			}
313 			QuickAbort = TRUE;
314 
315 			/* must parse sender first */
316 			delimptr = NULL;
317 			setsender(p, e, &delimptr, FALSE);
318 			p = delimptr;
319 			if (p != NULL && *p != '\0')
320 				*p++ = '\0';
321 
322 			/* now parse ESMTP arguments */
323 			msize = 0;
324 			for (; p != NULL && *p != '\0'; p++)
325 			{
326 				char *kp;
327 				char *vp;
328 
329 				/* locate the beginning of the keyword */
330 				while (isascii(*p) && isspace(*p))
331 					p++;
332 				if (*p == '\0')
333 					break;
334 				kp = p;
335 
336 				/* skip to the value portion */
337 				while (isascii(*p) && isalnum(*p) || *p == '-')
338 					p++;
339 				if (*p == '=')
340 				{
341 					*p++ = '\0';
342 					vp = p;
343 
344 					/* skip to the end of the value */
345 					while (*p != '\0' && *p != ' ' &&
346 					       !(isascii(*p) && iscntrl(*p)) &&
347 					       *p != '=')
348 						p++;
349 				}
350 
351 				if (*p != '\0')
352 					*p++ = '\0';
353 
354 				if (tTd(19, 1))
355 					printf("MAIL: got arg %s=%s\n", kp,
356 						vp == NULL ? "<null>" : vp);
357 
358 				if (strcasecmp(kp, "size") == 0)
359 				{
360 					if (vp == NULL)
361 					{
362 						usrerr("501 SIZE requires a value");
363 						/* NOTREACHED */
364 					}
365 					msize = atol(vp);
366 				}
367 				else if (strcasecmp(kp, "body") == 0)
368 				{
369 					if (vp == NULL)
370 					{
371 						usrerr("501 BODY requires a value");
372 						/* NOTREACHED */
373 					}
374 # ifdef MIME
375 					if (strcasecmp(vp, "8bitmime") == 0)
376 					{
377 						e->e_bodytype = "8BITMIME";
378 						SevenBit = FALSE;
379 					}
380 					else if (strcasecmp(vp, "7bit") == 0)
381 					{
382 						e->e_bodytype = "7BIT";
383 						SevenBit = TRUE;
384 					}
385 					else
386 					{
387 						usrerr("501 Unknown BODY type %s",
388 							vp);
389 					}
390 # endif
391 				}
392 				else
393 				{
394 					usrerr("501 %s parameter unrecognized", kp);
395 					/* NOTREACHED */
396 				}
397 			}
398 
399 			if (MaxMessageSize > 0 && msize > MaxMessageSize)
400 			{
401 				usrerr("552 Message size exceeds fixed maximum message size (%ld)",
402 					MaxMessageSize);
403 				/* NOTREACHED */
404 			}
405 
406 			if (!enoughspace(msize))
407 			{
408 				message("452 Insufficient disk space; try again later");
409 				break;
410 			}
411 			message("250 Sender ok");
412 			gotmail = TRUE;
413 			break;
414 
415 		  case CMDRCPT:		/* rcpt -- designate recipient */
416 			if (!gotmail)
417 			{
418 				usrerr("503 Need MAIL before RCPT");
419 				break;
420 			}
421 			SmtpPhase = "RCPT";
422 			if (setjmp(TopFrame) > 0)
423 			{
424 				e->e_flags &= ~EF_FATALERRS;
425 				break;
426 			}
427 			QuickAbort = TRUE;
428 			LogUsrErrs = TRUE;
429 
430 			if (e->e_sendmode != SM_DELIVER)
431 				e->e_flags |= EF_VRFYONLY;
432 
433 			p = skipword(p, "to");
434 			if (p == NULL)
435 				break;
436 			a = parseaddr(p, (ADDRESS *) NULL, 1, ' ', NULL, e);
437 			if (a == NULL)
438 				break;
439 			a->q_flags |= QPRIMARY;
440 			a = recipient(a, &e->e_sendqueue, e);
441 			if (Errors != 0)
442 				break;
443 
444 			/* no errors during parsing, but might be a duplicate */
445 			e->e_to = p;
446 			if (!bitset(QBADADDR, a->q_flags))
447 			{
448 				message("250 Recipient ok");
449 				nrcpts++;
450 			}
451 			else
452 			{
453 				/* punt -- should keep message in ADDRESS.... */
454 				message("550 Addressee unknown");
455 			}
456 			e->e_to = NULL;
457 			break;
458 
459 		  case CMDDATA:		/* data -- text of mail */
460 			SmtpPhase = "DATA";
461 			if (!gotmail)
462 			{
463 				message("503 Need MAIL command");
464 				break;
465 			}
466 			else if (e->e_nrcpts <= 0)
467 			{
468 				message("503 Need RCPT (recipient)");
469 				break;
470 			}
471 
472 			/* check to see if we need to re-expand aliases */
473 			for (a = e->e_sendqueue; a != NULL; a = a->q_next)
474 			{
475 				if (bitset(QVERIFIED, a->q_flags))
476 					break;
477 			}
478 
479 			/* collect the text of the message */
480 			SmtpPhase = "collect";
481 			collect(TRUE, a != NULL, e);
482 			e->e_flags &= ~EF_FATALERRS;
483 			if (Errors != 0)
484 				goto abortmessage;
485 
486 			/*
487 			**  Arrange to send to everyone.
488 			**	If sending to multiple people, mail back
489 			**		errors rather than reporting directly.
490 			**	In any case, don't mail back errors for
491 			**		anything that has happened up to
492 			**		now (the other end will do this).
493 			**	Truncate our transcript -- the mail has gotten
494 			**		to us successfully, and if we have
495 			**		to mail this back, it will be easier
496 			**		on the reader.
497 			**	Then send to everyone.
498 			**	Finally give a reply code.  If an error has
499 			**		already been given, don't mail a
500 			**		message back.
501 			**	We goose error returns by clearing error bit.
502 			*/
503 
504 			SmtpPhase = "delivery";
505 			if (nrcpts != 1 && a == NULL)
506 			{
507 				HoldErrs = TRUE;
508 				e->e_errormode = EM_MAIL;
509 			}
510 			e->e_xfp = freopen(queuename(e, 'x'), "w", e->e_xfp);
511 			id = e->e_id;
512 
513 			/* send to all recipients */
514 			sendall(e, a == NULL ? SM_DEFAULT : SM_QUEUE);
515 			e->e_to = NULL;
516 
517 			/* save statistics */
518 			markstats(e, (ADDRESS *) NULL);
519 
520 			/* issue success if appropriate and reset */
521 			if (Errors == 0 || HoldErrs)
522 				message("250 %s Message accepted for delivery", id);
523 
524 			if (bitset(EF_FATALERRS, e->e_flags) && !HoldErrs)
525 			{
526 				/* avoid sending back an extra message */
527 				e->e_flags &= ~EF_FATALERRS;
528 				e->e_flags |= EF_CLRQUEUE;
529 			}
530 			else
531 			{
532 				/* from now on, we have to operate silently */
533 				HoldErrs = TRUE;
534 				e->e_errormode = EM_MAIL;
535 
536 				/* if we just queued, poke it */
537 				if (a != NULL && e->e_sendmode != SM_QUEUE)
538 				{
539 					unlockqueue(e);
540 					dowork(id, TRUE, TRUE, e);
541 					e->e_id = NULL;
542 				}
543 			}
544 
545   abortmessage:
546 			/* if in a child, pop back to our parent */
547 			if (InChild)
548 				finis();
549 
550 			/* clean up a bit */
551 			gotmail = FALSE;
552 			dropenvelope(e);
553 			CurEnv = e = newenvelope(e, CurEnv);
554 			e->e_flags = BlankEnvelope.e_flags;
555 			break;
556 
557 		  case CMDRSET:		/* rset -- reset state */
558 			message("250 Reset state");
559 			if (InChild)
560 				finis();
561 
562 			/* clean up a bit */
563 			gotmail = FALSE;
564 			dropenvelope(e);
565 			CurEnv = e = newenvelope(e, CurEnv);
566 			break;
567 
568 		  case CMDVRFY:		/* vrfy -- verify address */
569 		  case CMDEXPN:		/* expn -- expand address */
570 			vrfy = c->cmdcode == CMDVRFY;
571 			if (bitset(vrfy ? PRIV_NOVRFY : PRIV_NOEXPN,
572 						PrivacyFlags))
573 			{
574 				if (vrfy)
575 					message("252 Who's to say?");
576 				else
577 					message("502 That's none of your business");
578 				break;
579 			}
580 			else if (!gothello &&
581 				 bitset(vrfy ? PRIV_NEEDVRFYHELO : PRIV_NEEDEXPNHELO,
582 						PrivacyFlags))
583 			{
584 				message("503 I demand that you introduce yourself first");
585 				break;
586 			}
587 			if (runinchild(vrfy ? "SMTP-VRFY" : "SMTP-EXPN", e) > 0)
588 				break;
589 #ifdef LOG
590 			if (LogLevel > 5)
591 				syslog(LOG_INFO, "%s: %s", CurHostName, inp);
592 #endif
593 			vrfyqueue = NULL;
594 			QuickAbort = TRUE;
595 			if (vrfy)
596 				e->e_flags |= EF_VRFYONLY;
597 			(void) sendtolist(p, (ADDRESS *) NULL, &vrfyqueue, e);
598 			if (Errors != 0)
599 			{
600 				if (InChild)
601 					finis();
602 				break;
603 			}
604 			while (vrfyqueue != NULL)
605 			{
606 				register ADDRESS *a = vrfyqueue->q_next;
607 				char *code;
608 
609 				while (a != NULL && bitset(QDONTSEND|QBADADDR, a->q_flags))
610 					a = a->q_next;
611 
612 				if (!bitset(QDONTSEND|QBADADDR, vrfyqueue->q_flags))
613 					printvrfyaddr(vrfyqueue, a == NULL);
614 				else if (a == NULL)
615 					message("554 Self destructive alias loop");
616 				vrfyqueue = a;
617 			}
618 			if (InChild)
619 				finis();
620 			break;
621 
622 		  case CMDHELP:		/* help -- give user info */
623 			help(p);
624 			break;
625 
626 		  case CMDNOOP:		/* noop -- do nothing */
627 			message("200 OK");
628 			break;
629 
630 		  case CMDQUIT:		/* quit -- leave mail */
631 			message("221 %s closing connection", MyHostName);
632 			if (InChild)
633 				ExitStat = EX_QUIT;
634 			finis();
635 
636 		  case CMDVERB:		/* set verbose mode */
637 			if (bitset(PRIV_NOEXPN, PrivacyFlags))
638 			{
639 				/* this would give out the same info */
640 				message("502 Verbose unavailable");
641 				break;
642 			}
643 			Verbose = TRUE;
644 			e->e_sendmode = SM_DELIVER;
645 			message("250 Verbose mode");
646 			break;
647 
648 		  case CMDONEX:		/* doing one transaction only */
649 			OneXact = TRUE;
650 			message("250 Only one transaction");
651 			break;
652 
653 # ifdef SMTPDEBUG
654 		  case CMDDBGQSHOW:	/* show queues */
655 			printf("Send Queue=");
656 			printaddr(e->e_sendqueue, TRUE);
657 			break;
658 
659 		  case CMDDBGDEBUG:	/* set debug mode */
660 			tTsetup(tTdvect, sizeof tTdvect, "0-99.1");
661 			tTflag(p);
662 			message("200 Debug set");
663 			break;
664 
665 # else /* not SMTPDEBUG */
666 
667 		  case CMDDBGQSHOW:	/* show queues */
668 		  case CMDDBGDEBUG:	/* set debug mode */
669 # ifdef LOG
670 			if (LogLevel > 0)
671 				syslog(LOG_NOTICE,
672 				    "\"%s\" command from %s (%s)",
673 				    c->cmdname, RealHostName,
674 				    anynet_ntoa(&RealHostAddr));
675 # endif
676 			/* FALL THROUGH */
677 # endif /* SMTPDEBUG */
678 
679 		  case CMDERROR:	/* unknown command */
680 			message("500 Command unrecognized");
681 			break;
682 
683 		  default:
684 			errno = 0;
685 			syserr("500 smtp: unknown code %d", c->cmdcode);
686 			break;
687 		}
688 	}
689 }
690 /*
691 **  SKIPWORD -- skip a fixed word.
692 **
693 **	Parameters:
694 **		p -- place to start looking.
695 **		w -- word to skip.
696 **
697 **	Returns:
698 **		p following w.
699 **		NULL on error.
700 **
701 **	Side Effects:
702 **		clobbers the p data area.
703 */
704 
705 static char *
706 skipword(p, w)
707 	register char *p;
708 	char *w;
709 {
710 	register char *q;
711 
712 	/* find beginning of word */
713 	while (isascii(*p) && isspace(*p))
714 		p++;
715 	q = p;
716 
717 	/* find end of word */
718 	while (*p != '\0' && *p != ':' && !(isascii(*p) && isspace(*p)))
719 		p++;
720 	while (isascii(*p) && isspace(*p))
721 		*p++ = '\0';
722 	if (*p != ':')
723 	{
724 	  syntax:
725 		message("501 Syntax error");
726 		Errors++;
727 		return (NULL);
728 	}
729 	*p++ = '\0';
730 	while (isascii(*p) && isspace(*p))
731 		p++;
732 
733 	/* see if the input word matches desired word */
734 	if (strcasecmp(q, w))
735 		goto syntax;
736 
737 	return (p);
738 }
739 /*
740 **  PRINTVRFYADDR -- print an entry in the verify queue
741 **
742 **	Parameters:
743 **		a -- the address to print
744 **		last -- set if this is the last one.
745 **
746 **	Returns:
747 **		none.
748 **
749 **	Side Effects:
750 **		Prints the appropriate 250 codes.
751 */
752 
753 printvrfyaddr(a, last)
754 	register ADDRESS *a;
755 	bool last;
756 {
757 	char fmtbuf[20];
758 
759 	strcpy(fmtbuf, "250");
760 	fmtbuf[3] = last ? ' ' : '-';
761 
762 	if (a->q_fullname == NULL)
763 	{
764 		if (strchr(a->q_user, '@') == NULL)
765 			strcpy(&fmtbuf[4], "<%s@%s>");
766 		else
767 			strcpy(&fmtbuf[4], "<%s>");
768 		message(fmtbuf, a->q_user, MyHostName);
769 	}
770 	else
771 	{
772 		if (strchr(a->q_user, '@') == NULL)
773 			strcpy(&fmtbuf[4], "%s <%s@%s>");
774 		else
775 			strcpy(&fmtbuf[4], "%s <%s>");
776 		message(fmtbuf, a->q_fullname, a->q_user, MyHostName);
777 	}
778 }
779 /*
780 **  HELP -- implement the HELP command.
781 **
782 **	Parameters:
783 **		topic -- the topic we want help for.
784 **
785 **	Returns:
786 **		none.
787 **
788 **	Side Effects:
789 **		outputs the help file to message output.
790 */
791 
792 help(topic)
793 	char *topic;
794 {
795 	register FILE *hf;
796 	int len;
797 	char buf[MAXLINE];
798 	bool noinfo;
799 
800 	if (HelpFile == NULL || (hf = fopen(HelpFile, "r")) == NULL)
801 	{
802 		/* no help */
803 		errno = 0;
804 		message("502 HELP not implemented");
805 		return;
806 	}
807 
808 	if (topic == NULL || *topic == '\0')
809 		topic = "smtp";
810 	else
811 		makelower(topic);
812 
813 	len = strlen(topic);
814 	noinfo = TRUE;
815 
816 	while (fgets(buf, sizeof buf, hf) != NULL)
817 	{
818 		if (strncmp(buf, topic, len) == 0)
819 		{
820 			register char *p;
821 
822 			p = strchr(buf, '\t');
823 			if (p == NULL)
824 				p = buf;
825 			else
826 				p++;
827 			fixcrlf(p, TRUE);
828 			message("214-%s", p);
829 			noinfo = FALSE;
830 		}
831 	}
832 
833 	if (noinfo)
834 		message("504 HELP topic unknown");
835 	else
836 		message("214 End of HELP info");
837 	(void) fclose(hf);
838 }
839 /*
840 **  RUNINCHILD -- return twice -- once in the child, then in the parent again
841 **
842 **	Parameters:
843 **		label -- a string used in error messages
844 **
845 **	Returns:
846 **		zero in the child
847 **		one in the parent
848 **
849 **	Side Effects:
850 **		none.
851 */
852 
853 runinchild(label, e)
854 	char *label;
855 	register ENVELOPE *e;
856 {
857 	int childpid;
858 
859 	if (!OneXact)
860 	{
861 		childpid = dofork();
862 		if (childpid < 0)
863 		{
864 			syserr("%s: cannot fork", label);
865 			return (1);
866 		}
867 		if (childpid > 0)
868 		{
869 			auto int st;
870 
871 			/* parent -- wait for child to complete */
872 			setproctitle("srvrsmtp %s child wait", CurHostName);
873 			st = waitfor(childpid);
874 			if (st == -1)
875 				syserr("%s: lost child", label);
876 
877 			/* if we exited on a QUIT command, complete the process */
878 			if (st == (EX_QUIT << 8))
879 				finis();
880 
881 			return (1);
882 		}
883 		else
884 		{
885 			/* child */
886 			InChild = TRUE;
887 			QuickAbort = FALSE;
888 			clearenvelope(e, FALSE);
889 		}
890 	}
891 
892 	/* open alias database */
893 	initaliases(FALSE, e);
894 
895 	return (0);
896 }
897 
898 # endif /* SMTP */
899