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source: trunk/third/sendmail/src/srvrsmtp.c @ 12554

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Revision 12554, 33.6 KB checked in by danw, 26 years ago (diff)
This commit was generated by cvs2svn to compensate for changes in r12553, which included commits to RCS files with non-trunk default branches.

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1	/*
2	* Copyright (c) 1998 Sendmail, Inc. All rights reserved.
3	* Copyright (c) 1983, 1995-1997 Eric P. Allman. All rights reserved.
4	* Copyright (c) 1988, 1993
5	* The Regents of the University of California. All rights reserved.
6	*
7	* By using this file, you agree to the terms and conditions set
8	* forth in the LICENSE file which can be found at the top level of
9	* the sendmail distribution.
10	*
11	*/
12
13	# include "sendmail.h"
14
15	#ifndef lint
16	#if SMTP
17	static char sccsid[] = "@(#)srvrsmtp.c 8.187 (Berkeley) 10/23/1998 (with SMTP)";
18	#else
19	static char sccsid[] = "@(#)srvrsmtp.c 8.187 (Berkeley) 10/23/1998 (without SMTP)";
20	#endif
21	#endif /* not lint */
22
23	# include <errno.h>
24
25	# if SMTP
26
27	/*
28	** SMTP -- run the SMTP protocol.
29	**
30	** Parameters:
31	** nullserver -- if non-NULL, rejection message for
32	** all SMTP commands.
33	** e -- the envelope.
34	**
35	** Returns:
36	** never.
37	**
38	** Side Effects:
39	** Reads commands from the input channel and processes
40	** them.
41	*/
42
43	struct cmd
44	{
45	char cmdname; / command name */
46	int cmdcode; /* internal code, see below */
47	};
48
49	/* values for cmdcode */
50	# define CMDERROR 0 /* bad command */
51	# define CMDMAIL 1 /* mail -- designate sender */
52	# define CMDRCPT 2 /* rcpt -- designate recipient */
53	# define CMDDATA 3 /* data -- send message text */
54	# define CMDRSET 4 /* rset -- reset state */
55	# define CMDVRFY 5 /* vrfy -- verify address */
56	# define CMDEXPN 6 /* expn -- expand address */
57	# define CMDNOOP 7 /* noop -- do nothing */
58	# define CMDQUIT 8 /* quit -- close connection and die */
59	# define CMDHELO 9 /* helo -- be polite */
60	# define CMDHELP 10 /* help -- give usage info */
61	# define CMDEHLO 11 /* ehlo -- extended helo (RFC 1425) */
62	# define CMDETRN 12 /* etrn -- flush queue */
63	/* non-standard commands */
64	# define CMDONEX 16 /* onex -- sending one transaction only */
65	# define CMDVERB 17 /* verb -- go into verbose mode */
66	# define CMDXUSR 18 /* xusr -- initial (user) submission */
67	/* use this to catch and log "door handle" attempts on your system */
68	# define CMDLOGBOGUS 23 /* bogus command that should be logged */
69	/* debugging-only commands, only enabled if SMTPDEBUG is defined */
70	# define CMDDBGQSHOW 24 /* showq -- show send queue */
71	# define CMDDBGDEBUG 25 /* debug -- set debug mode */
72
73	static struct cmd CmdTab[] =
74	{
75	{ "mail", CMDMAIL },
76	{ "rcpt", CMDRCPT },
77	{ "data", CMDDATA },
78	{ "rset", CMDRSET },
79	{ "vrfy", CMDVRFY },
80	{ "expn", CMDEXPN },
81	{ "help", CMDHELP },
82	{ "noop", CMDNOOP },
83	{ "quit", CMDQUIT },
84	{ "helo", CMDHELO },
85	{ "ehlo", CMDEHLO },
86	{ "etrn", CMDETRN },
87	{ "verb", CMDVERB },
88	{ "onex", CMDONEX },
89	{ "xusr", CMDXUSR },
90	/* remaining commands are here only to trap and log attempts to use them */
91	{ "showq", CMDDBGQSHOW },
92	{ "debug", CMDDBGDEBUG },
93	{ "wiz", CMDLOGBOGUS },
94
95	{ NULL, CMDERROR }
96	};
97
98	bool OneXact = FALSE; /* one xaction only this run */
99	char CurSmtpClient; / who's at the other end of channel */
100
101	static char skipword __P((char volatile, char *));
102
103
104	#define MAXBADCOMMANDS 25 /* maximum number of bad commands */
105	#define MAXNOOPCOMMANDS 20 /* max "noise" commands before slowdown */
106	#define MAXHELOCOMMANDS 3 /* max HELO/EHLO commands before slowdown */
107	#define MAXVRFYCOMMANDS 6 /* max VRFY/EXPN commands before slowdown */
108	#define MAXETRNCOMMANDS 8 /* max ETRN commands before slowdown */
109
110	void
111	smtp(nullserver, e)
112	char *nullserver;
113	register ENVELOPE *volatile e;
114	{
115	register char *volatile p;
116	register struct cmd *c;
117	char *cmd;
118	auto ADDRESS *vrfyqueue;
119	ADDRESS *a;
120	volatile bool gotmail; /* mail command received */
121	volatile bool gothello; /* helo command received */
122	bool vrfy; /* set if this is a vrfy command */
123	char volatile protocol; / sending protocol */
124	char volatile sendinghost; / sending hostname */
125	char volatile peerhostname; / name of SMTP peer or "localhost" */
126	auto char *delimptr;
127	char *id;
128	volatile int nrcpts = 0; /* number of RCPT commands */
129	bool doublequeue;
130	volatile bool discard;
131	volatile int badcommands = 0; /* count of bad commands */
132	volatile int nverifies = 0; /* count of VRFY/EXPN commands */
133	volatile int n_etrn = 0; /* count of ETRN commands */
134	volatile int n_noop = 0; /* count of NOOP/VERB/ONEX etc cmds */
135	volatile int n_helo = 0; /* count of HELO/EHLO commands */
136	bool ok;
137	volatile int lognullconnection = TRUE;
138	register char *q;
139	QUEUE_CHAR *new;
140	char inp[MAXLINE];
141	char cmdbuf[MAXLINE];
142	extern ENVELOPE BlankEnvelope;
143	extern void help __P((char *));
144	extern void settime __P((ENVELOPE *));
145	extern bool enoughdiskspace __P((long));
146	extern int runinchild __P((char , ENVELOPE ));
147	extern void checksmtpattack __P((volatile int , int, char , ENVELOPE *));
148
149	if (fileno(OutChannel) != fileno(stdout))
150	{
151	/* arrange for debugging output to go to remote host */
152	(void) dup2(fileno(OutChannel), fileno(stdout));
153	}
154	settime(e);
155	peerhostname = RealHostName;
156	if (peerhostname == NULL)
157	peerhostname = "localhost";
158	CurHostName = peerhostname;
159	CurSmtpClient = macvalue('_', e);
160	if (CurSmtpClient == NULL)
161	CurSmtpClient = CurHostName;
162
163	/* check_relay may have set discard bit, save for later */
164	discard = bitset(EF_DISCARD, e->e_flags);
165
166	sm_setproctitle(TRUE, "server %s startup", CurSmtpClient);
167	#if DAEMON
168	if (LogLevel > 11)
169	{
170	/* log connection information */
171	sm_syslog(LOG_INFO, NOQID,
172	"SMTP connect from %.100s (%.100s)",
173	CurSmtpClient, anynet_ntoa(&RealHostAddr));
174	}
175	#endif
176
177	/* output the first line, inserting "ESMTP" as second word */
178	expand(SmtpGreeting, inp, sizeof inp, e);
179	p = strchr(inp, '\n');
180	if (p != NULL)
181	*p++ = '\0';
182	id = strchr(inp, ' ');
183	if (id == NULL)
184	id = &inp[strlen(inp)];
185	cmd = p == NULL ? "220 %.s ESMTP%s" : "220-%.s ESMTP%s";
186	message(cmd, id - inp, inp, id);
187
188	/* output remaining lines */
189	while ((id = p) != NULL && (p = strchr(id, '\n')) != NULL)
190	{
191	*p++ = '\0';
192	if (isascii(id) && isspace(id))
193	id++;
194	message("220-%s", id);
195	}
196	if (id != NULL)
197	{
198	if (isascii(id) && isspace(id))
199	id++;
200	message("220 %s", id);
201	}
202
203	protocol = NULL;
204	sendinghost = macvalue('s', e);
205	gothello = FALSE;
206	gotmail = FALSE;
207	for (;;)
208	{
209	/* arrange for backout */
210	(void) setjmp(TopFrame);
211	QuickAbort = FALSE;
212	HoldErrs = FALSE;
213	SuprErrs = FALSE;
214	LogUsrErrs = FALSE;
215	OnlyOneError = TRUE;
216	e->e_flags &= ~(EF_VRFYONLY\|EF_GLOBALERRS);
217
218	/* setup for the read */
219	e->e_to = NULL;
220	Errors = 0;
221	(void) fflush(stdout);
222
223	/* read the input line */
224	SmtpPhase = "server cmd read";
225	sm_setproctitle(TRUE, "server %s cmd read", CurSmtpClient);
226	p = sfgets(inp, sizeof inp, InChannel, TimeOuts.to_nextcommand,
227	SmtpPhase);
228
229	/* handle errors */
230	if (p == NULL)
231	{
232	/* end of file, just die */
233	disconnect(1, e);
234	message("421 %s Lost input channel from %s",
235	MyHostName, CurSmtpClient);
236	if (LogLevel > (gotmail ? 1 : 19))
237	sm_syslog(LOG_NOTICE, e->e_id,
238	"lost input channel from %.100s",
239	CurSmtpClient);
240	if (lognullconnection && LogLevel > 5)
241	sm_syslog(LOG_INFO, NULL,
242	"Null connection from %.100s",
243	CurSmtpClient);
244
245	/*
246	** If have not accepted mail (DATA), do not bounce
247	** bad addresses back to sender.
248	*/
249	if (bitset(EF_CLRQUEUE, e->e_flags))
250	e->e_sendqueue = NULL;
251
252	if (InChild)
253	ExitStat = EX_QUIT;
254	finis(TRUE, ExitStat);
255	}
256
257	/* clean up end of line */
258	fixcrlf(inp, TRUE);
259
260	/* echo command to transcript */
261	if (e->e_xfp != NULL)
262	fprintf(e->e_xfp, "<<< %s\n", inp);
263
264	if (LogLevel >= 15)
265	sm_syslog(LOG_INFO, e->e_id,
266	"<-- %s",
267	inp);
268
269	if (e->e_id == NULL)
270	sm_setproctitle(TRUE, "%s: %.80s", CurSmtpClient, inp);
271	else
272	sm_setproctitle(TRUE, "%s %s: %.80s", e->e_id, CurSmtpClient, inp);
273
274	/* break off command */
275	for (p = inp; isascii(p) && isspace(p); p++)
276	continue;
277	cmd = cmdbuf;
278	while (*p != '\0' &&
279	!(isascii(p) && isspace(p)) &&
280	cmd < &cmdbuf[sizeof cmdbuf - 2])
281	cmd++ = p++;
282	*cmd = '\0';
283
284	/* throw away leading whitespace */
285	while (isascii(p) && isspace(p))
286	p++;
287
288	/* decode command */
289	for (c = CmdTab; c->cmdname != NULL; c++)
290	{
291	if (!strcasecmp(c->cmdname, cmdbuf))
292	break;
293	}
294
295	/* reset errors */
296	errno = 0;
297
298	/*
299	** Process command.
300	**
301	** If we are running as a null server, return 550
302	** to everything.
303	*/
304
305	if (nullserver != NULL)
306	{
307	switch (c->cmdcode)
308	{
309	case CMDQUIT:
310	case CMDHELO:
311	case CMDEHLO:
312	case CMDNOOP:
313	/* process normally */
314	break;
315
316	default:
317	if (++badcommands > MAXBADCOMMANDS)
318	sleep(1);
319	usrerr("550 %s", nullserver);
320	continue;
321	}
322	}
323
324	/* non-null server */
325	switch (c->cmdcode)
326	{
327	case CMDMAIL:
328	case CMDEXPN:
329	case CMDVRFY:
330	case CMDETRN:
331	lognullconnection = FALSE;
332	}
333
334	switch (c->cmdcode)
335	{
336	case CMDHELO: /* hello -- introduce yourself */
337	case CMDEHLO: /* extended hello */
338	if (c->cmdcode == CMDEHLO)
339	{
340	protocol = "ESMTP";
341	SmtpPhase = "server EHLO";
342	}
343	else
344	{
345	protocol = "SMTP";
346	SmtpPhase = "server HELO";
347	}
348
349	/* avoid denial-of-service */
350	checksmtpattack(&n_helo, MAXHELOCOMMANDS, "HELO/EHLO", e);
351
352	/* check for duplicate HELO/EHLO per RFC 1651 4.2 */
353	if (gothello)
354	{
355	usrerr("503 %s Duplicate HELO/EHLO",
356	MyHostName);
357	break;
358	}
359
360	/* check for valid domain name (re 1123 5.2.5) */
361	if (*p == '\0' && !AllowBogusHELO)
362	{
363	usrerr("501 %s requires domain address",
364	cmdbuf);
365	break;
366	}
367
368	/* check for long domain name (hides Received: info) */
369	if (strlen(p) > MAXNAME)
370	{
371	usrerr("501 Invalid domain name");
372	break;
373	}
374
375	for (q = p; *q != '\0'; q++)
376	{
377	if (!isascii(*q))
378	break;
379	if (isalnum(*q))
380	continue;
381	if (isspace(*q))
382	{
383	*q = '\0';
384	break;
385	}
386	if (strchr("[].-_#", *q) == NULL)
387	break;
388	}
389	if (*q == '\0')
390	{
391	q = "pleased to meet you";
392	sendinghost = newstr(p);
393	}
394	else if (!AllowBogusHELO)
395	{
396	usrerr("501 Invalid domain name");
397	break;
398	}
399	else
400	{
401	q = "accepting invalid domain name";
402	}
403
404	gothello = TRUE;
405
406	/* print HELO response message */
407	if (c->cmdcode != CMDEHLO \|\| nullserver != NULL)
408	{
409	message("250 %s Hello %s, %s",
410	MyHostName, CurSmtpClient, q);
411	break;
412	}
413
414	message("250-%s Hello %s, %s",
415	MyHostName, CurSmtpClient, q);
416
417	/* print EHLO features list */
418	if (!bitset(PRIV_NOEXPN, PrivacyFlags))
419	{
420	message("250-EXPN");
421	if (!bitset(PRIV_NOVERB, PrivacyFlags))
422	message("250-VERB");
423	}
424	#if MIME8TO7
425	message("250-8BITMIME");
426	#endif
427	if (MaxMessageSize > 0)
428	message("250-SIZE %ld", MaxMessageSize);
429	else
430	message("250-SIZE");
431	#if DSN
432	if (SendMIMEErrors)
433	message("250-DSN");
434	#endif
435	message("250-ONEX");
436	if (!bitset(PRIV_NOETRN, PrivacyFlags))
437	message("250-ETRN");
438	message("250-XUSR");
439	message("250 HELP");
440	break;
441
442	case CMDMAIL: /* mail -- designate sender */
443	SmtpPhase = "server MAIL";
444
445	/* check for validity of this command */
446	if (!gothello && bitset(PRIV_NEEDMAILHELO, PrivacyFlags))
447	{
448	usrerr("503 Polite people say HELO first");
449	break;
450	}
451	if (gotmail)
452	{
453	usrerr("503 Sender already specified");
454	break;
455	}
456	if (InChild)
457	{
458	errno = 0;
459	syserr("503 Nested MAIL command: MAIL %s", p);
460	finis(TRUE, ExitStat);
461	}
462
463	/* make sure we know who the sending host is */
464	if (sendinghost == NULL)
465	sendinghost = peerhostname;
466
467	p = skipword(p, "from");
468	if (p == NULL)
469	break;
470
471	/* fork a subprocess to process this command */
472	if (runinchild("SMTP-MAIL", e) > 0)
473	break;
474	if (Errors > 0)
475	goto undo_subproc_no_pm;
476	if (!gothello)
477	{
478	auth_warning(e,
479	"%s didn't use HELO protocol",
480	CurSmtpClient);
481	}
482	#ifdef PICKY_HELO_CHECK
483	if (strcasecmp(sendinghost, peerhostname) != 0 &&
484	(strcasecmp(peerhostname, "localhost") != 0 \|\|
485	strcasecmp(sendinghost, MyHostName) != 0))
486	{
487	auth_warning(e, "Host %s claimed to be %s",
488	CurSmtpClient, sendinghost);
489	}
490	#endif
491
492	if (protocol == NULL)
493	protocol = "SMTP";
494	define('r', protocol, e);
495	define('s', sendinghost, e);
496	initsys(e);
497	if (Errors > 0)
498	goto undo_subproc_no_pm;
499	nrcpts = 0;
500	e->e_flags \|= EF_LOGSENDER\|EF_CLRQUEUE;
501	sm_setproctitle(TRUE, "%s %s: %.80s", e->e_id, CurSmtpClient, inp);
502
503	/* child -- go do the processing */
504	if (setjmp(TopFrame) > 0)
505	{
506	/* this failed -- undo work */
507	undo_subproc_no_pm:
508	e->e_flags &= ~EF_PM_NOTIFY;
509	undo_subproc:
510	if (InChild)
511	{
512	QuickAbort = FALSE;
513	SuprErrs = TRUE;
514	e->e_flags &= ~EF_FATALERRS;
515	finis(TRUE, ExitStat);
516	}
517	break;
518	}
519	QuickAbort = TRUE;
520
521	/* must parse sender first */
522	delimptr = NULL;
523	setsender(p, e, &delimptr, ' ', FALSE);
524	if (delimptr != NULL && *delimptr != '\0')
525	*delimptr++ = '\0';
526	if (Errors > 0)
527	goto undo_subproc_no_pm;
528
529	/* do config file checking of the sender */
530	if (rscheck("check_mail", p, NULL, e) != EX_OK \|\|
531	Errors > 0)
532	goto undo_subproc_no_pm;
533
534	/* check for possible spoofing */
535	if (RealUid != 0 && OpMode == MD_SMTP &&
536	!wordinclass(RealUserName, 't') &&
537	!bitnset(M_LOCALMAILER, e->e_from.q_mailer->m_flags) &&
538	strcmp(e->e_from.q_user, RealUserName) != 0)
539	{
540	auth_warning(e, "%s owned process doing -bs",
541	RealUserName);
542	}
543
544	/* now parse ESMTP arguments */
545	e->e_msgsize = 0;
546	p = delimptr;
547	while (p != NULL && *p != '\0')
548	{
549	char *kp;
550	char *vp = NULL;
551	extern void mail_esmtp_args __P((char , char , ENVELOPE *));
552
553	/* locate the beginning of the keyword */
554	while (isascii(p) && isspace(p))
555	p++;
556	if (*p == '\0')
557	break;
558	kp = p;
559
560	/* skip to the value portion */
561	while ((isascii(p) && isalnum(p)) \|\| *p == '-')
562	p++;
563	if (*p == '=')
564	{
565	*p++ = '\0';
566	vp = p;
567
568	/* skip to the end of the value */
569	while (p != '\0' && p != ' ' &&
570	!(isascii(p) && iscntrl(p)) &&
571	*p != '=')
572	p++;
573	}
574
575	if (*p != '\0')
576	*p++ = '\0';
577
578	if (tTd(19, 1))
579	printf("MAIL: got arg %s=\"%s\"\n", kp,
580	vp == NULL ? "<null>" : vp);
581
582	mail_esmtp_args(kp, vp, e);
583	if (Errors > 0)
584	goto undo_subproc_no_pm;
585	}
586	if (Errors > 0)
587	goto undo_subproc_no_pm;
588
589	if (MaxMessageSize > 0 && e->e_msgsize > MaxMessageSize)
590	{
591	usrerr("552 Message size exceeds fixed maximum message size (%ld)",
592	MaxMessageSize);
593	goto undo_subproc_no_pm;
594	}
595
596	if (!enoughdiskspace(e->e_msgsize))
597	{
598	usrerr("452 Insufficient disk space; try again later");
599	goto undo_subproc_no_pm;
600	}
601	if (Errors > 0)
602	goto undo_subproc_no_pm;
603	message("250 Sender ok");
604	gotmail = TRUE;
605	break;
606
607	case CMDRCPT: /* rcpt -- designate recipient */
608	if (!gotmail)
609	{
610	usrerr("503 Need MAIL before RCPT");
611	break;
612	}
613	SmtpPhase = "server RCPT";
614	if (setjmp(TopFrame) > 0)
615	{
616	e->e_flags &= ~EF_FATALERRS;
617	break;
618	}
619	QuickAbort = TRUE;
620	LogUsrErrs = TRUE;
621
622	/* limit flooding of our machine */
623	if (MaxRcptPerMsg > 0 && nrcpts >= MaxRcptPerMsg)
624	{
625	usrerr("452 Too many recipients");
626	break;
627	}
628
629	if (e->e_sendmode != SM_DELIVER)
630	e->e_flags \|= EF_VRFYONLY;
631
632	p = skipword(p, "to");
633	if (p == NULL)
634	break;
635	a = parseaddr(p, NULLADDR, RF_COPYALL, ' ', &delimptr, e);
636	if (Errors > 0)
637	break;
638	if (a == NULL)
639	{
640	usrerr("501 Missing recipient");
641	break;
642	}
643
644	if (delimptr != NULL && *delimptr != '\0')
645	*delimptr++ = '\0';
646
647	/* do config file checking of the recipient */
648	if (rscheck("check_rcpt", p, NULL, e) != EX_OK \|\|
649	Errors > 0)
650	break;
651
652	/* now parse ESMTP arguments */
653	p = delimptr;
654	while (p != NULL && *p != '\0')
655	{
656	char *kp;
657	char *vp = NULL;
658	extern void rcpt_esmtp_args __P((ADDRESS , char , char , ENVELOPE ));
659
660	/* locate the beginning of the keyword */
661	while (isascii(p) && isspace(p))
662	p++;
663	if (*p == '\0')
664	break;
665	kp = p;
666
667	/* skip to the value portion */
668	while ((isascii(p) && isalnum(p)) \|\| *p == '-')
669	p++;
670	if (*p == '=')
671	{
672	*p++ = '\0';
673	vp = p;
674
675	/* skip to the end of the value */
676	while (p != '\0' && p != ' ' &&
677	!(isascii(p) && iscntrl(p)) &&
678	*p != '=')
679	p++;
680	}
681
682	if (*p != '\0')
683	*p++ = '\0';
684
685	if (tTd(19, 1))
686	printf("RCPT: got arg %s=\"%s\"\n", kp,
687	vp == NULL ? "<null>" : vp);
688
689	rcpt_esmtp_args(a, kp, vp, e);
690	if (Errors > 0)
691	break;
692	}
693	if (Errors > 0)
694	break;
695
696	/* save in recipient list after ESMTP mods */
697	a = recipient(a, &e->e_sendqueue, 0, e);
698	if (Errors > 0)
699	break;
700
701	/* no errors during parsing, but might be a duplicate */
702	e->e_to = a->q_paddr;
703	if (!bitset(QBADADDR, a->q_flags))
704	{
705	message("250 Recipient ok%s",
706	bitset(QQUEUEUP, a->q_flags) ?
707	" (will queue)" : "");
708	nrcpts++;
709	}
710	else
711	{
712	/* punt -- should keep message in ADDRESS.... */
713	usrerr("550 Addressee unknown");
714	}
715	break;
716
717	case CMDDATA: /* data -- text of mail */
718	SmtpPhase = "server DATA";
719	if (!gotmail)
720	{
721	usrerr("503 Need MAIL command");
722	break;
723	}
724	else if (nrcpts <= 0)
725	{
726	usrerr("503 Need RCPT (recipient)");
727	break;
728	}
729
730	/* put back discard bit */
731	if (discard)
732	e->e_flags \|= EF_DISCARD;
733
734	/* check to see if we need to re-expand aliases */
735	/* also reset QBADADDR on already-diagnosted addrs */
736	doublequeue = FALSE;
737	for (a = e->e_sendqueue; a != NULL; a = a->q_next)
738	{
739	if (bitset(QVERIFIED, a->q_flags) &&
740	!bitset(EF_DISCARD, e->e_flags))
741	{
742	/* need to re-expand aliases */
743	doublequeue = TRUE;
744	}
745	if (bitset(QBADADDR, a->q_flags))
746	{
747	/* make this "go away" */
748	a->q_flags \|= QDONTSEND;
749	a->q_flags &= ~QBADADDR;
750	}
751	}
752
753	/* collect the text of the message */
754	SmtpPhase = "collect";
755	buffer_errors();
756	collect(InChannel, TRUE, NULL, e);
757	if (Errors > 0)
758	{
759	flush_errors(TRUE);
760	buffer_errors();
761	goto abortmessage;
762	}
763
764	/* make sure we actually do delivery */
765	e->e_flags &= ~EF_CLRQUEUE;
766
767	/* from now on, we have to operate silently */
768	buffer_errors();
769	e->e_errormode = EM_MAIL;
770
771	/*
772	** Arrange to send to everyone.
773	** If sending to multiple people, mail back
774	** errors rather than reporting directly.
775	** In any case, don't mail back errors for
776	** anything that has happened up to
777	** now (the other end will do this).
778	** Truncate our transcript -- the mail has gotten
779	** to us successfully, and if we have
780	** to mail this back, it will be easier
781	** on the reader.
782	** Then send to everyone.
783	** Finally give a reply code. If an error has
784	** already been given, don't mail a
785	** message back.
786	** We goose error returns by clearing error bit.
787	*/
788
789	SmtpPhase = "delivery";
790	e->e_xfp = freopen(queuename(e, 'x'), "w", e->e_xfp);
791	id = e->e_id;
792
793	if (doublequeue)
794	{
795	/* make sure it is in the queue */
796	queueup(e, FALSE);
797	}
798	else
799	{
800	/* send to all recipients */
801	sendall(e, SM_DEFAULT);
802	}
803	e->e_to = NULL;
804
805	/* issue success message */
806	message("250 %s Message accepted for delivery", id);
807
808	/* if we just queued, poke it */
809	if (doublequeue &&
810	e->e_sendmode != SM_QUEUE &&
811	e->e_sendmode != SM_DEFER)
812	{
813	CurrentLA = getla();
814
815	if (!shouldqueue(e->e_msgpriority, e->e_ctime))
816	{
817	unlockqueue(e);
818	(void) dowork(id, TRUE, TRUE, e);
819	}
820	}
821
822	abortmessage:
823	/* if in a child, pop back to our parent */
824	if (InChild)
825	finis(TRUE, ExitStat);
826
827	/* clean up a bit */
828	gotmail = FALSE;
829	dropenvelope(e, TRUE);
830	CurEnv = e = newenvelope(e, CurEnv);
831	e->e_flags = BlankEnvelope.e_flags;
832	break;
833
834	case CMDRSET: /* rset -- reset state */
835	if (tTd(94, 100))
836	message("451 Test failure");
837	else
838	message("250 Reset state");
839
840	/* arrange to ignore any current send list */
841	e->e_sendqueue = NULL;
842	e->e_flags \|= EF_CLRQUEUE;
843	if (InChild)
844	finis(TRUE, ExitStat);
845
846	/* clean up a bit */
847	gotmail = FALSE;
848	SuprErrs = TRUE;
849	dropenvelope(e, TRUE);
850	CurEnv = e = newenvelope(e, CurEnv);
851	break;
852
853	case CMDVRFY: /* vrfy -- verify address */
854	case CMDEXPN: /* expn -- expand address */
855	checksmtpattack(&nverifies, MAXVRFYCOMMANDS,
856	c->cmdcode == CMDVRFY ? "VRFY" : "EXPN", e);
857	vrfy = c->cmdcode == CMDVRFY;
858	if (bitset(vrfy ? PRIV_NOVRFY : PRIV_NOEXPN,
859	PrivacyFlags))
860	{
861	if (vrfy)
862	message("252 Cannot VRFY user; try RCPT to attempt delivery (or try finger)");
863	else
864	message("502 Sorry, we do not allow this operation");
865	if (LogLevel > 5)
866	sm_syslog(LOG_INFO, e->e_id,
867	"%.100s: %s [rejected]",
868	CurSmtpClient,
869	shortenstring(inp, MAXSHORTSTR));
870	break;
871	}
872	else if (!gothello &&
873	bitset(vrfy ? PRIV_NEEDVRFYHELO : PRIV_NEEDEXPNHELO,
874	PrivacyFlags))
875	{
876	usrerr("503 I demand that you introduce yourself first");
877	break;
878	}
879	if (runinchild(vrfy ? "SMTP-VRFY" : "SMTP-EXPN", e) > 0)
880	break;
881	if (Errors > 0)
882	goto undo_subproc;
883	if (LogLevel > 5)
884	sm_syslog(LOG_INFO, e->e_id,
885	"%.100s: %s",
886	CurSmtpClient,
887	shortenstring(inp, MAXSHORTSTR));
888	if (setjmp(TopFrame) > 0)
889	goto undo_subproc;
890	QuickAbort = TRUE;
891	vrfyqueue = NULL;
892	if (vrfy)
893	e->e_flags \|= EF_VRFYONLY;
894	while (p != '\0' && isascii(p) && isspace(*p))
895	p++;
896	if (*p == '\0')
897	{
898	usrerr("501 Argument required");
899	}
900	else
901	{
902	(void) sendtolist(p, NULLADDR, &vrfyqueue, 0, e);
903	}
904	if (Errors > 0)
905	goto undo_subproc;
906	if (vrfyqueue == NULL)
907	{
908	usrerr("554 Nothing to %s", vrfy ? "VRFY" : "EXPN");
909	}
910	while (vrfyqueue != NULL)
911	{
912	extern void printvrfyaddr __P((ADDRESS *, bool, bool));
913
914	a = vrfyqueue;
915	while ((a = a->q_next) != NULL &&
916	bitset(QDONTSEND\|QBADADDR, a->q_flags))
917	continue;
918	if (!bitset(QDONTSEND\|QBADADDR, vrfyqueue->q_flags))
919	printvrfyaddr(vrfyqueue, a == NULL, vrfy);
920	vrfyqueue = vrfyqueue->q_next;
921	}
922	if (InChild)
923	finis(TRUE, ExitStat);
924	break;
925
926	case CMDETRN: /* etrn -- force queue flush */
927	if (bitset(PRIV_NOETRN, PrivacyFlags))
928	{
929	message("502 Sorry, we do not allow this operation");
930	if (LogLevel > 5)
931	sm_syslog(LOG_INFO, e->e_id,
932	"%.100s: %s [rejected]",
933	CurSmtpClient,
934	shortenstring(inp, MAXSHORTSTR));
935	break;
936	}
937
938	if (strlen(p) <= 0)
939	{
940	usrerr("500 Parameter required");
941	break;
942	}
943
944	/* crude way to avoid denial-of-service attacks */
945	checksmtpattack(&n_etrn, MAXETRNCOMMANDS, "ETRN", e);
946
947	if (LogLevel > 5)
948	sm_syslog(LOG_INFO, e->e_id,
949	"%.100s: ETRN %s",
950	CurSmtpClient,
951	shortenstring(p, MAXSHORTSTR));
952
953	id = p;
954	if (*id == '@')
955	id++;
956	else
957	*--id = '@';
958
959	if ((new = (QUEUE_CHAR *)malloc(sizeof(QUEUE_CHAR))) == NULL)
960	{
961	syserr("500 ETRN out of memory");
962	break;
963	}
964	new->queue_match = id;
965	new->queue_next = NULL;
966	QueueLimitRecipient = new;
967	ok = runqueue(TRUE, TRUE);
968	free(QueueLimitRecipient);
969	QueueLimitRecipient = NULL;
970	if (ok && Errors == 0)
971	message("250 Queuing for node %s started", p);
972	break;
973
974	case CMDHELP: /* help -- give user info */
975	help(p);
976	break;
977
978	case CMDNOOP: /* noop -- do nothing */
979	checksmtpattack(&n_noop, MAXNOOPCOMMANDS, "NOOP", e);
980	message("250 OK");
981	break;
982
983	case CMDQUIT: /* quit -- leave mail */
984	message("221 %s closing connection", MyHostName);
985
986	doquit:
987	/* arrange to ignore any current send list */
988	e->e_sendqueue = NULL;
989
990	/* avoid future 050 messages */
991	disconnect(1, e);
992
993	if (InChild)
994	ExitStat = EX_QUIT;
995	if (lognullconnection && LogLevel > 5)
996	sm_syslog(LOG_INFO, NULL,
997	"Null connection from %.100s",
998	CurSmtpClient);
999	finis(TRUE, ExitStat);
1000
1001	case CMDVERB: /* set verbose mode */
1002	if (bitset(PRIV_NOEXPN, PrivacyFlags) \|\|
1003	bitset(PRIV_NOVERB, PrivacyFlags))
1004	{
1005	/* this would give out the same info */
1006	message("502 Verbose unavailable");
1007	break;
1008	}
1009	checksmtpattack(&n_noop, MAXNOOPCOMMANDS, "VERB", e);
1010	Verbose = 1;
1011	e->e_sendmode = SM_DELIVER;
1012	message("250 Verbose mode");
1013	break;
1014
1015	case CMDONEX: /* doing one transaction only */
1016	checksmtpattack(&n_noop, MAXNOOPCOMMANDS, "ONEX", e);
1017	OneXact = TRUE;
1018	message("250 Only one transaction");
1019	break;
1020
1021	case CMDXUSR: /* initial (user) submission */
1022	checksmtpattack(&n_noop, MAXNOOPCOMMANDS, "XUSR", e);
1023	UserSubmission = TRUE;
1024	message("250 Initial submission");
1025	break;
1026
1027	# if SMTPDEBUG
1028	case CMDDBGQSHOW: /* show queues */
1029	printf("Send Queue=");
1030	printaddr(e->e_sendqueue, TRUE);
1031	break;
1032
1033	case CMDDBGDEBUG: /* set debug mode */
1034	tTsetup(tTdvect, sizeof tTdvect, "0-99.1");
1035	tTflag(p);
1036	message("200 Debug set");
1037	break;
1038
1039	# else /* not SMTPDEBUG */
1040	case CMDDBGQSHOW: /* show queues */
1041	case CMDDBGDEBUG: /* set debug mode */
1042	# endif /* SMTPDEBUG */
1043	case CMDLOGBOGUS: /* bogus command */
1044	if (LogLevel > 0)
1045	sm_syslog(LOG_CRIT, e->e_id,
1046	"\"%s\" command from %.100s (%.100s)",
1047	c->cmdname, CurSmtpClient,
1048	anynet_ntoa(&RealHostAddr));
1049	/* FALL THROUGH */
1050
1051	case CMDERROR: /* unknown command */
1052	if (++badcommands > MAXBADCOMMANDS)
1053	{
1054	message("421 %s Too many bad commands; closing connection",
1055	MyHostName);
1056	goto doquit;
1057	}
1058
1059	usrerr("500 Command unrecognized: \"%s\"",
1060	shortenstring(inp, MAXSHORTSTR));
1061	break;
1062
1063	default:
1064	errno = 0;
1065	syserr("500 smtp: unknown code %d", c->cmdcode);
1066	break;
1067	}
1068	}
1069	}
1070	/*
1071	** CHECKSMTPATTACK -- check for denial-of-service attack by repetition
1072	**
1073	** Parameters:
1074	** pcounter -- pointer to a counter for this command.
1075	** maxcount -- maximum value for this counter before we
1076	** slow down.
1077	** cname -- command name for logging.
1078	** e -- the current envelope.
1079	**
1080	** Returns:
1081	** none.
1082	**
1083	** Side Effects:
1084	** Slows down if we seem to be under attack.
1085	*/
1086
1087	void
1088	checksmtpattack(pcounter, maxcount, cname, e)
1089	volatile int *pcounter;
1090	int maxcount;
1091	char *cname;
1092	ENVELOPE *e;
1093	{
1094	if (++(*pcounter) >= maxcount)
1095	{
1096	if (*pcounter == maxcount && LogLevel > 5)
1097	{
1098	sm_syslog(LOG_INFO, e->e_id,
1099	"%.100s: %.40s attack?",
1100	CurSmtpClient, cname);
1101	}
1102	sleep(*pcounter / maxcount);
1103	}
1104	}
1105	/*
1106	** SKIPWORD -- skip a fixed word.
1107	**
1108	** Parameters:
1109	** p -- place to start looking.
1110	** w -- word to skip.
1111	**
1112	** Returns:
1113	** p following w.
1114	** NULL on error.
1115	**
1116	** Side Effects:
1117	** clobbers the p data area.
1118	*/
1119
1120	static char *
1121	skipword(p, w)
1122	register char *volatile p;
1123	char *w;
1124	{
1125	register char *q;
1126	char *firstp = p;
1127
1128	/* find beginning of word */
1129	while (isascii(p) && isspace(p))
1130	p++;
1131	q = p;
1132
1133	/* find end of word */
1134	while (p != '\0' && p != ':' && !(isascii(p) && isspace(p)))
1135	p++;
1136	while (isascii(p) && isspace(p))
1137	*p++ = '\0';
1138	if (*p != ':')
1139	{
1140	syntax:
1141	usrerr("501 Syntax error in parameters scanning \"%s\"",
1142	shortenstring(firstp, MAXSHORTSTR));
1143	return (NULL);
1144	}
1145	*p++ = '\0';
1146	while (isascii(p) && isspace(p))
1147	p++;
1148
1149	if (*p == '\0')
1150	goto syntax;
1151
1152	/* see if the input word matches desired word */
1153	if (strcasecmp(q, w))
1154	goto syntax;
1155
1156	return (p);
1157	}
1158	/*
1159	** MAIL_ESMTP_ARGS -- process ESMTP arguments from MAIL line
1160	**
1161	** Parameters:
1162	** kp -- the parameter key.
1163	** vp -- the value of that parameter.
1164	** e -- the envelope.
1165	**
1166	** Returns:
1167	** none.
1168	*/
1169
1170	void
1171	mail_esmtp_args(kp, vp, e)
1172	char *kp;
1173	char *vp;
1174	ENVELOPE *e;
1175	{
1176	if (strcasecmp(kp, "size") == 0)
1177	{
1178	if (vp == NULL)
1179	{
1180	usrerr("501 SIZE requires a value");
1181	/* NOTREACHED */
1182	}
1183	# if defined(__STDC__) && !defined(BROKEN_ANSI_LIBRARY)
1184	e->e_msgsize = strtoul(vp, (char **) NULL, 10);
1185	# else
1186	e->e_msgsize = strtol(vp, (char **) NULL, 10);
1187	# endif
1188	}
1189	else if (strcasecmp(kp, "body") == 0)
1190	{
1191	if (vp == NULL)
1192	{
1193	usrerr("501 BODY requires a value");
1194	/* NOTREACHED */
1195	}
1196	else if (strcasecmp(vp, "8bitmime") == 0)
1197	{
1198	SevenBitInput = FALSE;
1199	}
1200	else if (strcasecmp(vp, "7bit") == 0)
1201	{
1202	SevenBitInput = TRUE;
1203	}
1204	else
1205	{
1206	usrerr("501 Unknown BODY type %s",
1207	vp);
1208	/* NOTREACHED */
1209	}
1210	e->e_bodytype = newstr(vp);
1211	}
1212	else if (strcasecmp(kp, "envid") == 0)
1213	{
1214	if (vp == NULL)
1215	{
1216	usrerr("501 ENVID requires a value");
1217	/* NOTREACHED */
1218	}
1219	if (!xtextok(vp))
1220	{
1221	usrerr("501 Syntax error in ENVID parameter value");
1222	/* NOTREACHED */
1223	}
1224	if (e->e_envid != NULL)
1225	{
1226	usrerr("501 Duplicate ENVID parameter");
1227	/* NOTREACHED */
1228	}
1229	e->e_envid = newstr(vp);
1230	}
1231	else if (strcasecmp(kp, "ret") == 0)
1232	{
1233	if (vp == NULL)
1234	{
1235	usrerr("501 RET requires a value");
1236	/* NOTREACHED */
1237	}
1238	if (bitset(EF_RET_PARAM, e->e_flags))
1239	{
1240	usrerr("501 Duplicate RET parameter");
1241	/* NOTREACHED */
1242	}
1243	e->e_flags \|= EF_RET_PARAM;
1244	if (strcasecmp(vp, "hdrs") == 0)
1245	e->e_flags \|= EF_NO_BODY_RETN;
1246	else if (strcasecmp(vp, "full") != 0)
1247	{
1248	usrerr("501 Bad argument \"%s\" to RET", vp);
1249	/* NOTREACHED */
1250	}
1251	}
1252	else
1253	{
1254	usrerr("501 %s parameter unrecognized", kp);
1255	/* NOTREACHED */
1256	}
1257	}
1258	/*
1259	** RCPT_ESMTP_ARGS -- process ESMTP arguments from RCPT line
1260	**
1261	** Parameters:
1262	** a -- the address corresponding to the To: parameter.
1263	** kp -- the parameter key.
1264	** vp -- the value of that parameter.
1265	** e -- the envelope.
1266	**
1267	** Returns:
1268	** none.
1269	*/
1270
1271	void
1272	rcpt_esmtp_args(a, kp, vp, e)
1273	ADDRESS *a;
1274	char *kp;
1275	char *vp;
1276	ENVELOPE *e;
1277	{
1278	if (strcasecmp(kp, "notify") == 0)
1279	{
1280	char *p;
1281
1282	if (vp == NULL)
1283	{
1284	usrerr("501 NOTIFY requires a value");
1285	/* NOTREACHED */
1286	}
1287	a->q_flags &= ~(QPINGONSUCCESS\|QPINGONFAILURE\|QPINGONDELAY);
1288	a->q_flags \|= QHASNOTIFY;
1289	if (strcasecmp(vp, "never") == 0)
1290	return;
1291	for (p = vp; p != NULL; vp = p)
1292	{
1293	p = strchr(p, ',');
1294	if (p != NULL)
1295	*p++ = '\0';
1296	if (strcasecmp(vp, "success") == 0)
1297	a->q_flags \|= QPINGONSUCCESS;
1298	else if (strcasecmp(vp, "failure") == 0)
1299	a->q_flags \|= QPINGONFAILURE;
1300	else if (strcasecmp(vp, "delay") == 0)
1301	a->q_flags \|= QPINGONDELAY;
1302	else
1303	{
1304	usrerr("501 Bad argument \"%s\" to NOTIFY",
1305	vp);
1306	/* NOTREACHED */
1307	}
1308	}
1309	}
1310	else if (strcasecmp(kp, "orcpt") == 0)
1311	{
1312	if (vp == NULL)
1313	{
1314	usrerr("501 ORCPT requires a value");
1315	/* NOTREACHED */
1316	}
1317	if (strchr(vp, ';') == NULL \|\| !xtextok(vp))
1318	{
1319	usrerr("501 Syntax error in ORCPT parameter value");
1320	/* NOTREACHED */
1321	}
1322	if (a->q_orcpt != NULL)
1323	{
1324	usrerr("501 Duplicate ORCPT parameter");
1325	/* NOTREACHED */
1326	}
1327	a->q_orcpt = newstr(vp);
1328	}
1329	else
1330	{
1331	usrerr("501 %s parameter unrecognized", kp);
1332	/* NOTREACHED */
1333	}
1334	}
1335	/*
1336	** PRINTVRFYADDR -- print an entry in the verify queue
1337	**
1338	** Parameters:
1339	** a -- the address to print
1340	** last -- set if this is the last one.
1341	** vrfy -- set if this is a VRFY command.
1342	**
1343	** Returns:
1344	** none.
1345	**
1346	** Side Effects:
1347	** Prints the appropriate 250 codes.
1348	*/
1349
1350	void
1351	printvrfyaddr(a, last, vrfy)
1352	register ADDRESS *a;
1353	bool last;
1354	bool vrfy;
1355	{
1356	char fmtbuf[20];
1357
1358	if (vrfy && a->q_mailer != NULL &&
1359	!bitnset(M_VRFY250, a->q_mailer->m_flags))
1360	strcpy(fmtbuf, "252");
1361	else
1362	strcpy(fmtbuf, "250");
1363	fmtbuf[3] = last ? ' ' : '-';
1364
1365	if (a->q_fullname == NULL)
1366	{
1367	if (strchr(a->q_user, '@') == NULL)
1368	strcpy(&fmtbuf[4], "<%s@%s>");
1369	else
1370	strcpy(&fmtbuf[4], "<%s>");
1371	message(fmtbuf, a->q_user, MyHostName);
1372	}
1373	else
1374	{
1375	if (strchr(a->q_user, '@') == NULL)
1376	strcpy(&fmtbuf[4], "%s <%s@%s>");
1377	else
1378	strcpy(&fmtbuf[4], "%s <%s>");
1379	message(fmtbuf, a->q_fullname, a->q_user, MyHostName);
1380	}
1381	}
1382	/*
1383	** RUNINCHILD -- return twice -- once in the child, then in the parent again
1384	**
1385	** Parameters:
1386	** label -- a string used in error messages
1387	**
1388	** Returns:
1389	** zero in the child
1390	** one in the parent
1391	**
1392	** Side Effects:
1393	** none.
1394	*/
1395
1396	int
1397	runinchild(label, e)
1398	char *label;
1399	register ENVELOPE *e;
1400	{
1401	pid_t childpid;
1402
1403	if (!OneXact)
1404	{
1405	/*
1406	** Disable child process reaping, in case ETRN has preceeded
1407	** MAIL command, and then fork.
1408	*/
1409
1410	(void) blocksignal(SIGCHLD);
1411
1412	childpid = dofork();
1413	if (childpid < 0)
1414	{
1415	syserr("451 %s: cannot fork", label);
1416	(void) releasesignal(SIGCHLD);
1417	return (1);
1418	}
1419	if (childpid > 0)
1420	{
1421	auto int st;
1422
1423	/* parent -- wait for child to complete */
1424	sm_setproctitle(TRUE, "server %s child wait", CurSmtpClient);
1425	st = waitfor(childpid);
1426	if (st == -1)
1427	syserr("451 %s: lost child", label);
1428	else if (!WIFEXITED(st))
1429	syserr("451 %s: died on signal %d",
1430	label, st & 0177);
1431
1432	/* if we exited on a QUIT command, complete the process */
1433	if (WEXITSTATUS(st) == EX_QUIT)
1434	{
1435	disconnect(1, e);
1436	finis(TRUE, ExitStat);
1437	}
1438
1439	/* restore the child signal */
1440	(void) releasesignal(SIGCHLD);
1441
1442	return (1);
1443	}
1444	else
1445	{
1446	/* child */
1447	InChild = TRUE;
1448	QuickAbort = FALSE;
1449	clearenvelope(e, FALSE);
1450	(void) setsignal(SIGCHLD, SIG_DFL);
1451	(void) releasesignal(SIGCHLD);
1452	}
1453	}
1454	return (0);
1455	}
1456
1457	# endif /* SMTP */
1458	/*
1459	** HELP -- implement the HELP command.
1460	**
1461	** Parameters:
1462	** topic -- the topic we want help for.
1463	**
1464	** Returns:
1465	** none.
1466	**
1467	** Side Effects:
1468	** outputs the help file to message output.
1469	*/
1470
1471	void
1472	help(topic)
1473	char *topic;
1474	{
1475	register FILE *hf;
1476	int len;
1477	bool noinfo;
1478	int sff = SFF_OPENASROOT\|SFF_REGONLY;
1479	char buf[MAXLINE];
1480	extern char Version[];
1481
1482	if (DontLockReadFiles)
1483	sff \|= SFF_NOLOCK;
1484	if (!bitset(DBS_HELPFILEINUNSAFEDIRPATH, DontBlameSendmail))
1485	sff \|= SFF_SAFEDIRPATH;
1486
1487	if (HelpFile == NULL \|\|
1488	(hf = safefopen(HelpFile, O_RDONLY, 0444, sff)) == NULL)
1489	{
1490	/* no help */
1491	errno = 0;
1492	message("502 Sendmail %s -- HELP not implemented", Version);
1493	return;
1494	}
1495
1496	if (topic == NULL \|\| *topic == '\0')
1497	{
1498	topic = "smtp";
1499	message("214-This is Sendmail version %s", Version);
1500	noinfo = FALSE;
1501	}
1502	else
1503	{
1504	makelower(topic);
1505	noinfo = TRUE;
1506	}
1507
1508	len = strlen(topic);
1509
1510	while (fgets(buf, sizeof buf, hf) != NULL)
1511	{
1512	if (strncmp(buf, topic, len) == 0)
1513	{
1514	register char *p;
1515
1516	p = strchr(buf, '\t');
1517	if (p == NULL)
1518	p = buf;
1519	else
1520	p++;
1521	fixcrlf(p, TRUE);
1522	message("214-%s", p);
1523	noinfo = FALSE;
1524	}
1525	}
1526
1527	if (noinfo)
1528	message("504 HELP topic \"%.10s\" unknown", topic);
1529	else
1530	message("214 End of HELP info");
1531	(void) fclose(hf);
1532	}

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