xref: /freebsd/contrib/sendmail/src/mci.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*
2  * Copyright (c) 1998-2005, 2010 Proofpoint, Inc. and its suppliers.
3  *	All rights reserved.
4  * Copyright (c) 1995-1997 Eric P. Allman.  All rights reserved.
5  * Copyright (c) 1988, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * By using this file, you agree to the terms and conditions set
9  * forth in the LICENSE file which can be found at the top level of
10  * the sendmail distribution.
11  *
12  */
13 
14 #include <sendmail.h>
15 
16 SM_RCSID("@(#)$Id: mci.c,v 8.225 2013-11-22 20:51:56 ca Exp $")
17 
18 #if NETINET || NETINET6
19 # include <arpa/inet.h>
20 #endif
21 
22 #include <dirent.h>
23 #if STARTTLS
24 # include <tls.h>
25 #endif
26 
27 static int	mci_generate_persistent_path __P((const char *, char *,
28 						  int, bool));
29 static bool	mci_load_persistent __P((MCI *));
30 static void	mci_uncache __P((MCI **, bool));
31 static void	mci_clear __P((MCI *));
32 static int	mci_lock_host_statfile __P((MCI *));
33 static int	mci_read_persistent __P((SM_FILE_T *, MCI *));
34 
35 /*
36 **  Mail Connection Information (MCI) Caching Module.
37 **
38 **	There are actually two separate things cached.  The first is
39 **	the set of all open connections -- these are stored in a
40 **	(small) list.  The second is stored in the symbol table; it
41 **	has the overall status for all hosts, whether or not there
42 **	is a connection open currently.
43 **
44 **	There should never be too many connections open (since this
45 **	could flood the socket table), nor should a connection be
46 **	allowed to sit idly for too long.
47 **
48 **	MaxMciCache is the maximum number of open connections that
49 **	will be supported.
50 **
51 **	MciCacheTimeout is the time (in seconds) that a connection
52 **	is permitted to survive without activity.
53 **
54 **	We actually try any cached connections by sending a RSET
55 **	before we use them; if the RSET fails we close down the
56 **	connection and reopen it (see smtpprobe()).
57 **
58 **	The persistent MCI code is donated by Mark Lovell and Paul
59 **	Vixie.  It is based on the long term host status code in KJS
60 **	written by Paul but has been adapted by Mark to fit into the
61 **	MCI structure.
62 */
63 
64 static MCI	**MciCache;		/* the open connection cache */
65 
66 /*
67 **  MCI_CACHE -- enter a connection structure into the open connection cache
68 **
69 **	This may cause something else to be flushed.
70 **
71 **	Parameters:
72 **		mci -- the connection to cache.
73 **
74 **	Returns:
75 **		none.
76 */
77 
78 void
79 mci_cache(mci)
80 	register MCI *mci;
81 {
82 	register MCI **mcislot;
83 
84 	/*
85 	**  Find the best slot.  This may cause expired connections
86 	**  to be closed.
87 	*/
88 
89 	mcislot = mci_scan(mci);
90 	if (mcislot == NULL)
91 	{
92 		/* we don't support caching */
93 		return;
94 	}
95 
96 	if (mci->mci_host == NULL)
97 		return;
98 
99 	/* if this is already cached, we are done */
100 	if (bitset(MCIF_CACHED, mci->mci_flags))
101 		return;
102 
103 	/* otherwise we may have to clear the slot */
104 	if (*mcislot != NULL)
105 		mci_uncache(mcislot, true);
106 
107 	if (tTd(42, 5))
108 		sm_dprintf("mci_cache: caching %p (%s) in slot %d\n",
109 			(void *)mci, mci->mci_host, (int) (mcislot - MciCache));
110 	if (tTd(91, 100))
111 		sm_syslog(LOG_DEBUG, CurEnv->e_id,
112 			  "mci_cache: caching %lx (%.100s) in slot %d",
113 			  (unsigned long) mci, mci->mci_host,
114 			  (int) (mcislot - MciCache));
115 
116 	*mcislot = mci;
117 	mci->mci_flags |= MCIF_CACHED;
118 }
119 /*
120 **  MCI_SCAN -- scan the cache, flush junk, and return best slot
121 **
122 **	Parameters:
123 **		savemci -- never flush this one.  Can be null.
124 **
125 **	Returns:
126 **		The LRU (or empty) slot.
127 */
128 
129 MCI **
130 mci_scan(savemci)
131 	MCI *savemci;
132 {
133 	time_t now;
134 	register MCI **bestmci;
135 	register MCI *mci;
136 	register int i;
137 
138 	if (MaxMciCache <= 0)
139 	{
140 		/* we don't support caching */
141 		return NULL;
142 	}
143 
144 	if (MciCache == NULL)
145 	{
146 		/* first call */
147 		MciCache = (MCI **) sm_pmalloc_x(MaxMciCache * sizeof(*MciCache));
148 		memset((char *) MciCache, '\0', MaxMciCache * sizeof(*MciCache));
149 		return &MciCache[0];
150 	}
151 
152 	now = curtime();
153 	bestmci = &MciCache[0];
154 	for (i = 0; i < MaxMciCache; i++)
155 	{
156 		mci = MciCache[i];
157 		if (mci == NULL || mci->mci_state == MCIS_CLOSED)
158 		{
159 			bestmci = &MciCache[i];
160 			continue;
161 		}
162 		if ((mci->mci_lastuse + MciCacheTimeout <= now ||
163 		     (mci->mci_mailer != NULL &&
164 		      mci->mci_mailer->m_maxdeliveries > 0 &&
165 		      mci->mci_deliveries + 1 >= mci->mci_mailer->m_maxdeliveries))&&
166 		    mci != savemci)
167 		{
168 			/* connection idle too long or too many deliveries */
169 			bestmci = &MciCache[i];
170 
171 			/* close it */
172 			mci_uncache(bestmci, true);
173 			continue;
174 		}
175 		if (*bestmci == NULL)
176 			continue;
177 		if (mci->mci_lastuse < (*bestmci)->mci_lastuse)
178 			bestmci = &MciCache[i];
179 	}
180 	return bestmci;
181 }
182 /*
183 **  MCI_UNCACHE -- remove a connection from a slot.
184 **
185 **	May close a connection.
186 **
187 **	Parameters:
188 **		mcislot -- the slot to empty.
189 **		doquit -- if true, send QUIT protocol on this connection.
190 **			  if false, we are assumed to be in a forked child;
191 **				all we want to do is close the file(s).
192 **
193 **	Returns:
194 **		none.
195 */
196 
197 static void
198 mci_uncache(mcislot, doquit)
199 	register MCI **mcislot;
200 	bool doquit;
201 {
202 	register MCI *mci;
203 	extern ENVELOPE BlankEnvelope;
204 
205 	mci = *mcislot;
206 	if (mci == NULL)
207 		return;
208 	*mcislot = NULL;
209 	if (mci->mci_host == NULL)
210 		return;
211 
212 	mci_unlock_host(mci);
213 
214 	if (tTd(42, 5))
215 		sm_dprintf("mci_uncache: uncaching %p (%s) from slot %d (%d)\n",
216 			(void *)mci, mci->mci_host, (int) (mcislot - MciCache),
217 			   doquit);
218 	if (tTd(91, 100))
219 		sm_syslog(LOG_DEBUG, CurEnv->e_id,
220 			  "mci_uncache: uncaching %lx (%.100s) from slot %d (%d)",
221 			  (unsigned long) mci, mci->mci_host,
222 			  (int) (mcislot - MciCache), doquit);
223 
224 	mci->mci_deliveries = 0;
225 	if (doquit)
226 	{
227 		message("Closing connection to %s", mci->mci_host);
228 
229 		mci->mci_flags &= ~MCIF_CACHED;
230 
231 		/* only uses the envelope to flush the transcript file */
232 		if (mci->mci_state != MCIS_CLOSED)
233 			smtpquit(mci->mci_mailer, mci, &BlankEnvelope);
234 #if XLA
235 		xla_host_end(mci->mci_host);
236 #endif
237 	}
238 	else
239 	{
240 		if (mci->mci_in != NULL)
241 			(void) sm_io_close(mci->mci_in, SM_TIME_DEFAULT);
242 		if (mci->mci_out != NULL)
243 			(void) sm_io_close(mci->mci_out, SM_TIME_DEFAULT);
244 		mci->mci_in = mci->mci_out = NULL;
245 		mci->mci_state = MCIS_CLOSED;
246 		mci->mci_exitstat = EX_OK;
247 		mci->mci_errno = 0;
248 		mci->mci_flags = 0;
249 
250 		mci->mci_retryrcpt = false;
251 		mci->mci_tolist = NULL;
252 		mci->mci_okrcpts = 0;
253 	}
254 
255 	SM_FREE(mci->mci_status);
256 	SM_FREE(mci->mci_rstatus);
257 	SM_FREE(mci->mci_heloname);
258 	mci_clear(mci);
259 	if (mci->mci_rpool != NULL)
260 	{
261 		sm_rpool_free(mci->mci_rpool);
262 		mci->mci_macro.mac_rpool = NULL;
263 		mci->mci_rpool = NULL;
264 	}
265 }
266 /*
267 **  MCI_FLUSH -- flush the entire cache
268 **
269 **	Parameters:
270 **		doquit -- if true, send QUIT protocol.
271 **			  if false, just close the connection.
272 **		allbut -- but leave this one open.
273 **
274 **	Returns:
275 **		none.
276 */
277 
278 void
279 mci_flush(doquit, allbut)
280 	bool doquit;
281 	MCI *allbut;
282 {
283 	register int i;
284 
285 	if (MciCache == NULL)
286 		return;
287 
288 	for (i = 0; i < MaxMciCache; i++)
289 	{
290 		if (allbut != MciCache[i])
291 			mci_uncache(&MciCache[i], doquit);
292 	}
293 }
294 
295 /*
296 **  MCI_CLR_EXTENSIONS -- clear knowledge about SMTP extensions
297 **
298 **	Parameters:
299 **		mci -- the connection to clear.
300 **
301 **	Returns:
302 **		none.
303 */
304 
305 void
306 mci_clr_extensions(mci)
307 	MCI *mci;
308 {
309 	if (mci == NULL)
310 		return;
311 
312 	mci->mci_flags &= ~MCIF_EXTENS;
313 	mci->mci_maxsize = 0;
314 	mci->mci_min_by = 0;
315 #if SASL
316 	mci->mci_saslcap = NULL;
317 #endif
318 }
319 
320 /*
321 **  MCI_CLEAR -- clear mci
322 **
323 **	Parameters:
324 **		mci -- the connection to clear.
325 **
326 **	Returns:
327 **		none.
328 */
329 
330 static void
331 mci_clear(mci)
332 	MCI *mci;
333 {
334 	if (mci == NULL)
335 		return;
336 
337 	mci->mci_maxsize = 0;
338 	mci->mci_min_by = 0;
339 	mci->mci_deliveries = 0;
340 #if SASL
341 	if (bitset(MCIF_AUTHACT, mci->mci_flags))
342 		sasl_dispose(&mci->mci_conn);
343 #endif
344 #if STARTTLS
345 	if (bitset(MCIF_TLSACT, mci->mci_flags) && mci->mci_ssl != NULL)
346 		SM_SSL_FREE(mci->mci_ssl);
347 #endif
348 
349 	/* which flags to preserve? */
350 	mci->mci_flags &= MCIF_CACHED;
351 	mactabclear(&mci->mci_macro);
352 }
353 
354 
355 /*
356 **  MCI_GET -- get information about a particular host
357 **
358 **	Parameters:
359 **		host -- host to look for.
360 **		m -- mailer.
361 **
362 **	Returns:
363 **		mci for this host (might be new).
364 */
365 
366 MCI *
367 mci_get(host, m)
368 	char *host;
369 	MAILER *m;
370 {
371 	register MCI *mci;
372 	register STAB *s;
373 	extern SOCKADDR CurHostAddr;
374 
375 	/* clear CurHostAddr so we don't get a bogus address with this name */
376 	memset(&CurHostAddr, '\0', sizeof(CurHostAddr));
377 
378 	/* clear out any expired connections */
379 	(void) mci_scan(NULL);
380 
381 	if (m->m_mno < 0)
382 		syserr("!negative mno %d (%s)", m->m_mno, m->m_name);
383 
384 	s = stab(host, ST_MCI + m->m_mno, ST_ENTER);
385 	mci = &s->s_mci;
386 
387 	/* initialize per-message data */
388 	mci->mci_retryrcpt = false;
389 	mci->mci_tolist = NULL;
390 	mci->mci_okrcpts = 0;
391 	mci->mci_flags &= ~MCIF_NOTSTICKY;
392 
393 	if (mci->mci_rpool == NULL)
394 		mci->mci_rpool = sm_rpool_new_x(NULL);
395 
396 	if (mci->mci_macro.mac_rpool == NULL)
397 		mci->mci_macro.mac_rpool = mci->mci_rpool;
398 
399 	/*
400 	**  We don't need to load the persistent data if we have data
401 	**  already loaded in the cache.
402 	*/
403 
404 	if (mci->mci_host == NULL &&
405 	    (mci->mci_host = s->s_name) != NULL &&
406 	    !mci_load_persistent(mci))
407 	{
408 		if (tTd(42, 2))
409 			sm_dprintf("mci_get(%s %s): lock failed\n",
410 				host, m->m_name);
411 		mci->mci_exitstat = EX_TEMPFAIL;
412 		mci->mci_state = MCIS_CLOSED;
413 		mci->mci_statfile = NULL;
414 		return mci;
415 	}
416 
417 	if (tTd(42, 2))
418 	{
419 		sm_dprintf("mci_get(%s %s): mci_state=%d, _flags=%lx, _exitstat=%d, _errno=%d\n",
420 			host, m->m_name, mci->mci_state, mci->mci_flags,
421 			mci->mci_exitstat, mci->mci_errno);
422 	}
423 
424 	if (mci->mci_state == MCIS_OPEN)
425 	{
426 		/* poke the connection to see if it's still alive */
427 		(void) smtpprobe(mci);
428 
429 		/* reset the stored state in the event of a timeout */
430 		if (mci->mci_state != MCIS_OPEN)
431 		{
432 			mci->mci_errno = 0;
433 			mci->mci_exitstat = EX_OK;
434 			mci->mci_state = MCIS_CLOSED;
435 		}
436 		else
437 		{
438 			/* get peer host address */
439 			/* (this should really be in the mci struct) */
440 			SOCKADDR_LEN_T socklen = sizeof(CurHostAddr);
441 
442 			(void) getpeername(sm_io_getinfo(mci->mci_in,
443 							 SM_IO_WHAT_FD, NULL),
444 				(struct sockaddr *) &CurHostAddr, &socklen);
445 		}
446 	}
447 	if (mci->mci_state == MCIS_CLOSED)
448 	{
449 		time_t now = curtime();
450 
451 		/* if this info is stale, ignore it */
452 		if (mci->mci_lastuse + MciInfoTimeout <= now)
453 		{
454 			mci->mci_lastuse = now;
455 			mci->mci_errno = 0;
456 			mci->mci_exitstat = EX_OK;
457 		}
458 		mci_clear(mci);
459 	}
460 
461 	return mci;
462 }
463 
464 /*
465 **  MCI_CLOSE -- (forcefully) close files used for a connection.
466 **	Note: this is a last resort, usually smtpquit() or endmailer()
467 **		should be used to close a connection.
468 **
469 **	Parameters:
470 **		mci -- the connection to close.
471 **		where -- where has this been called?
472 **
473 **	Returns:
474 **		none.
475 */
476 
477 void
478 mci_close(mci, where)
479 	MCI *mci;
480 	char *where;
481 {
482 	bool dumped;
483 
484 	if (mci == NULL)
485 		return;
486 	dumped = false;
487 	if (mci->mci_out != NULL)
488 	{
489 		if (tTd(56, 1))
490 		{
491 			sm_dprintf("mci_close: mci_out!=NULL, where=%s\n",
492 				where);
493 			mci_dump(sm_debug_file(), mci, false);
494 			dumped = true;
495 		}
496 		(void) sm_io_close(mci->mci_out, SM_TIME_DEFAULT);
497 		mci->mci_out = NULL;
498 	}
499 	if (mci->mci_in != NULL)
500 	{
501 		if (tTd(56, 1))
502 		{
503 			sm_dprintf("mci_close: mci_in!=NULL, where=%s\n",
504 				where);
505 			if (!dumped)
506 				mci_dump(sm_debug_file(), mci, false);
507 		}
508 		(void) sm_io_close(mci->mci_in, SM_TIME_DEFAULT);
509 		mci->mci_in = NULL;
510 	}
511 	mci->mci_state = MCIS_CLOSED;
512 }
513 
514 /*
515 **  MCI_NEW -- allocate new MCI structure
516 **
517 **	Parameters:
518 **		rpool -- if non-NULL: allocate from that rpool.
519 **
520 **	Returns:
521 **		mci (new).
522 */
523 
524 MCI *
525 mci_new(rpool)
526 	SM_RPOOL_T *rpool;
527 {
528 	register MCI *mci;
529 
530 	if (rpool == NULL)
531 		mci = (MCI *) sm_malloc_x(sizeof(*mci));
532 	else
533 		mci = (MCI *) sm_rpool_malloc_x(rpool, sizeof(*mci));
534 	memset((char *) mci, '\0', sizeof(*mci));
535 	mci->mci_rpool = sm_rpool_new_x(NULL);
536 	mci->mci_macro.mac_rpool = mci->mci_rpool;
537 	return mci;
538 }
539 /*
540 **  MCI_MATCH -- check connection cache for a particular host
541 **
542 **	Parameters:
543 **		host -- host to look for.
544 **		m -- mailer.
545 **
546 **	Returns:
547 **		true iff open connection exists.
548 */
549 
550 bool
551 mci_match(host, m)
552 	char *host;
553 	MAILER *m;
554 {
555 	register MCI *mci;
556 	register STAB *s;
557 
558 	if (m->m_mno < 0 || m->m_mno > MAXMAILERS)
559 		return false;
560 	s = stab(host, ST_MCI + m->m_mno, ST_FIND);
561 	if (s == NULL)
562 		return false;
563 
564 	mci = &s->s_mci;
565 	return mci->mci_state == MCIS_OPEN;
566 }
567 /*
568 **  MCI_SETSTAT -- set status codes in MCI structure.
569 **
570 **	Parameters:
571 **		mci -- the MCI structure to set.
572 **		xstat -- the exit status code.
573 **		dstat -- the DSN status code.
574 **		rstat -- the SMTP status code.
575 **
576 **	Returns:
577 **		none.
578 */
579 
580 void
581 mci_setstat(mci, xstat, dstat, rstat)
582 	MCI *mci;
583 	int xstat;
584 	char *dstat;
585 	char *rstat;
586 {
587 	/* protocol errors should never be interpreted as sticky */
588 	if (xstat != EX_NOTSTICKY && xstat != EX_PROTOCOL)
589 		mci->mci_exitstat = xstat;
590 
591 	SM_FREE(mci->mci_status);
592 	if (dstat != NULL)
593 		mci->mci_status = sm_strdup_x(dstat);
594 
595 	SM_FREE(mci->mci_rstatus);
596 	if (rstat != NULL)
597 		mci->mci_rstatus = sm_strdup_x(rstat);
598 }
599 /*
600 **  MCI_DUMP -- dump the contents of an MCI structure.
601 **
602 **	Parameters:
603 **		fp -- output file pointer
604 **		mci -- the MCI structure to dump.
605 **
606 **	Returns:
607 **		none.
608 **
609 **	Side Effects:
610 **		none.
611 */
612 
613 struct mcifbits
614 {
615 	int	mcif_bit;	/* flag bit */
616 	char	*mcif_name;	/* flag name */
617 };
618 static struct mcifbits	MciFlags[] =
619 {
620 	{ MCIF_CACHED,		"CACHED"	},
621 	{ MCIF_ESMTP,		"ESMTP"		},
622 	{ MCIF_EXPN,		"EXPN"		},
623 	{ MCIF_SIZE,		"SIZE"		},
624 	{ MCIF_8BITMIME,	"8BITMIME"	},
625 	{ MCIF_7BIT,		"7BIT"		},
626 	{ MCIF_INHEADER,	"INHEADER"	},
627 	{ MCIF_CVT8TO7,		"CVT8TO7"	},
628 	{ MCIF_DSN,		"DSN"		},
629 	{ MCIF_8BITOK,		"8BITOK"	},
630 	{ MCIF_CVT7TO8,		"CVT7TO8"	},
631 	{ MCIF_INMIME,		"INMIME"	},
632 	{ MCIF_AUTH,		"AUTH"		},
633 	{ MCIF_AUTH2,		"AUTH2"		},
634 	{ MCIF_AUTHACT,		"AUTHACT"	},
635 	{ MCIF_ENHSTAT,		"ENHSTAT"	},
636 	{ MCIF_PIPELINED,	"PIPELINED"	},
637 	{ MCIF_VERB,		"VERB"	},
638 #if STARTTLS
639 	{ MCIF_TLS,		"TLS"		},
640 	{ MCIF_TLSACT,		"TLSACT"	},
641 #endif
642 	{ MCIF_DLVR_BY,		"DLVR_BY"	},
643 	{ MCIF_INLONGLINE,	"INLONGLINE"	},
644 	{ MCIF_NOTSTICKY,	"NOTSTICKY"	},
645 	{ 0,			NULL		}
646 };
647 
648 void
649 mci_dump(fp, mci, logit)
650 	SM_FILE_T *fp;
651 	register MCI *mci;
652 	bool logit;
653 {
654 	register char *p;
655 	char *sep;
656 	char buf[4000];
657 
658 	sep = logit ? " " : "\n\t";
659 	p = buf;
660 	(void) sm_snprintf(p, SPACELEFT(buf, p), "MCI@%p: ", (void *)mci);
661 	p += strlen(p);
662 	if (mci == NULL)
663 	{
664 		(void) sm_snprintf(p, SPACELEFT(buf, p), "NULL");
665 		goto printit;
666 	}
667 	(void) sm_snprintf(p, SPACELEFT(buf, p), "flags=%lx", mci->mci_flags);
668 	p += strlen(p);
669 
670 	/*
671 	**  The following check is just for paranoia.  It protects the
672 	**  assignment in the if() clause. If there's not some minimum
673 	**  amount of space we can stop right now. The check will not
674 	**  trigger as long as sizeof(buf)=4000.
675 	*/
676 
677 	if (p >= buf + sizeof(buf) - 4)
678 		goto printit;
679 	if (mci->mci_flags != 0)
680 	{
681 		struct mcifbits *f;
682 
683 		*p++ = '<';	/* protected above */
684 		for (f = MciFlags; f->mcif_bit != 0; f++)
685 		{
686 			if (!bitset(f->mcif_bit, mci->mci_flags))
687 				continue;
688 			(void) sm_strlcpyn(p, SPACELEFT(buf, p), 2,
689 					   f->mcif_name, ",");
690 			p += strlen(p);
691 		}
692 		p[-1] = '>';
693 	}
694 
695 	/* Note: sm_snprintf() takes care of NULL arguments for %s */
696 	(void) sm_snprintf(p, SPACELEFT(buf, p),
697 		",%serrno=%d, herrno=%d, exitstat=%d, state=%d, pid=%d,%s",
698 		sep, mci->mci_errno, mci->mci_herrno,
699 		mci->mci_exitstat, mci->mci_state, (int) mci->mci_pid, sep);
700 	p += strlen(p);
701 	(void) sm_snprintf(p, SPACELEFT(buf, p),
702 		"maxsize=%ld, phase=%s, mailer=%s,%s",
703 		mci->mci_maxsize, mci->mci_phase,
704 		mci->mci_mailer == NULL ? "NULL" : mci->mci_mailer->m_name,
705 		sep);
706 	p += strlen(p);
707 	(void) sm_snprintf(p, SPACELEFT(buf, p),
708 		"status=%s, rstatus=%s,%s",
709 		mci->mci_status, mci->mci_rstatus, sep);
710 	p += strlen(p);
711 	(void) sm_snprintf(p, SPACELEFT(buf, p),
712 		"host=%s, lastuse=%s",
713 		mci->mci_host, ctime(&mci->mci_lastuse));
714 printit:
715 	if (logit)
716 		sm_syslog(LOG_DEBUG, CurEnv->e_id, "%.1000s", buf);
717 	else
718 		(void) sm_io_fprintf(fp, SM_TIME_DEFAULT, "%s\n", buf);
719 }
720 /*
721 **  MCI_DUMP_ALL -- print the entire MCI cache
722 **
723 **	Parameters:
724 **		fp -- output file pointer
725 **		logit -- if set, log the result instead of printing
726 **			to stdout.
727 **
728 **	Returns:
729 **		none.
730 */
731 
732 void
733 mci_dump_all(fp, logit)
734 	SM_FILE_T *fp;
735 	bool logit;
736 {
737 	register int i;
738 
739 	if (MciCache == NULL)
740 		return;
741 
742 	for (i = 0; i < MaxMciCache; i++)
743 		mci_dump(fp, MciCache[i], logit);
744 }
745 /*
746 **  MCI_LOCK_HOST -- Lock host while sending.
747 **
748 **	If we are contacting a host, we'll need to
749 **	update the status information in the host status
750 **	file, and if we want to do that, we ought to have
751 **	locked it. This has the (according to some)
752 **	desirable effect of serializing connectivity with
753 **	remote hosts -- i.e.: one connection to a given
754 **	host at a time.
755 **
756 **	Parameters:
757 **		mci -- containing the host we want to lock.
758 **
759 **	Returns:
760 **		EX_OK	    -- got the lock.
761 **		EX_TEMPFAIL -- didn't get the lock.
762 */
763 
764 int
765 mci_lock_host(mci)
766 	MCI *mci;
767 {
768 	if (mci == NULL)
769 	{
770 		if (tTd(56, 1))
771 			sm_dprintf("mci_lock_host: NULL mci\n");
772 		return EX_OK;
773 	}
774 
775 	if (!SingleThreadDelivery)
776 		return EX_OK;
777 
778 	return mci_lock_host_statfile(mci);
779 }
780 
781 static int
782 mci_lock_host_statfile(mci)
783 	MCI *mci;
784 {
785 	int save_errno = errno;
786 	int retVal = EX_OK;
787 	char fname[MAXPATHLEN];
788 
789 	if (HostStatDir == NULL || mci->mci_host == NULL)
790 		return EX_OK;
791 
792 	if (tTd(56, 2))
793 		sm_dprintf("mci_lock_host: attempting to lock %s\n",
794 			   mci->mci_host);
795 
796 	if (mci_generate_persistent_path(mci->mci_host, fname, sizeof(fname),
797 					 true) < 0)
798 	{
799 		/* of course this should never happen */
800 		if (tTd(56, 2))
801 			sm_dprintf("mci_lock_host: Failed to generate host path for %s\n",
802 				   mci->mci_host);
803 
804 		retVal = EX_TEMPFAIL;
805 		goto cleanup;
806 	}
807 
808 	mci->mci_statfile = safefopen(fname, O_RDWR, FileMode,
809 				      SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH|SFF_CREAT);
810 
811 	if (mci->mci_statfile == NULL)
812 	{
813 		syserr("mci_lock_host: cannot create host lock file %s", fname);
814 		goto cleanup;
815 	}
816 
817 	if (!lockfile(sm_io_getinfo(mci->mci_statfile, SM_IO_WHAT_FD, NULL),
818 		      fname, "", LOCK_EX|LOCK_NB))
819 	{
820 		if (tTd(56, 2))
821 			sm_dprintf("mci_lock_host: couldn't get lock on %s\n",
822 				fname);
823 		(void) sm_io_close(mci->mci_statfile, SM_TIME_DEFAULT);
824 		mci->mci_statfile = NULL;
825 		retVal = EX_TEMPFAIL;
826 		goto cleanup;
827 	}
828 
829 	if (tTd(56, 12) && mci->mci_statfile != NULL)
830 		sm_dprintf("mci_lock_host: Sanity check -- lock is good\n");
831 
832 cleanup:
833 	errno = save_errno;
834 	return retVal;
835 }
836 /*
837 **  MCI_UNLOCK_HOST -- unlock host
838 **
839 **	Clean up the lock on a host, close the file, let
840 **	someone else use it.
841 **
842 **	Parameters:
843 **		mci -- us.
844 **
845 **	Returns:
846 **		nothing.
847 */
848 
849 void
850 mci_unlock_host(mci)
851 	MCI *mci;
852 {
853 	int save_errno = errno;
854 
855 	if (mci == NULL)
856 	{
857 		if (tTd(56, 1))
858 			sm_dprintf("mci_unlock_host: NULL mci\n");
859 		return;
860 	}
861 
862 	if (HostStatDir == NULL || mci->mci_host == NULL)
863 		return;
864 
865 	if (!SingleThreadDelivery && mci_lock_host_statfile(mci) == EX_TEMPFAIL)
866 	{
867 		if (tTd(56, 1))
868 			sm_dprintf("mci_unlock_host: stat file already locked\n");
869 	}
870 	else
871 	{
872 		if (tTd(56, 2))
873 			sm_dprintf("mci_unlock_host: store prior to unlock\n");
874 		mci_store_persistent(mci);
875 	}
876 
877 	if (mci->mci_statfile != NULL)
878 	{
879 		(void) sm_io_close(mci->mci_statfile, SM_TIME_DEFAULT);
880 		mci->mci_statfile = NULL;
881 	}
882 
883 	errno = save_errno;
884 }
885 /*
886 **  MCI_LOAD_PERSISTENT -- load persistent host info
887 **
888 **	Load information about host that is kept
889 **	in common for all running sendmails.
890 **
891 **	Parameters:
892 **		mci -- the host/connection to load persistent info for.
893 **
894 **	Returns:
895 **		true -- lock was successful
896 **		false -- lock failed
897 */
898 
899 static bool
900 mci_load_persistent(mci)
901 	MCI *mci;
902 {
903 	int save_errno = errno;
904 	bool locked = true;
905 	SM_FILE_T *fp;
906 	char fname[MAXPATHLEN];
907 
908 	if (mci == NULL)
909 	{
910 		if (tTd(56, 1))
911 			sm_dprintf("mci_load_persistent: NULL mci\n");
912 		return true;
913 	}
914 
915 	if (IgnoreHostStatus || HostStatDir == NULL || mci->mci_host == NULL)
916 		return true;
917 
918 	/* Already have the persistent information in memory */
919 	if (SingleThreadDelivery && mci->mci_statfile != NULL)
920 		return true;
921 
922 	if (tTd(56, 1))
923 		sm_dprintf("mci_load_persistent: Attempting to load persistent information for %s\n",
924 			   mci->mci_host);
925 
926 	if (mci_generate_persistent_path(mci->mci_host, fname, sizeof(fname),
927 					 false) < 0)
928 	{
929 		/* Not much we can do if the file isn't there... */
930 		if (tTd(56, 1))
931 			sm_dprintf("mci_load_persistent: Couldn't generate host path\n");
932 		goto cleanup;
933 	}
934 
935 	fp = safefopen(fname, O_RDONLY, FileMode,
936 		       SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH);
937 	if (fp == NULL)
938 	{
939 		/* I can't think of any reason this should ever happen */
940 		if (tTd(56, 1))
941 			sm_dprintf("mci_load_persistent: open(%s): %s\n",
942 				fname, sm_errstring(errno));
943 		goto cleanup;
944 	}
945 
946 	FileName = fname;
947 	locked = lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), fname, "",
948 			  LOCK_SH|LOCK_NB);
949 	if (locked)
950 	{
951 		(void) mci_read_persistent(fp, mci);
952 		(void) lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), fname,
953 				"", LOCK_UN);
954 	}
955 	FileName = NULL;
956 	(void) sm_io_close(fp, SM_TIME_DEFAULT);
957 
958 cleanup:
959 	errno = save_errno;
960 	return locked;
961 }
962 /*
963 **  MCI_READ_PERSISTENT -- read persistent host status file
964 **
965 **	Parameters:
966 **		fp -- the file pointer to read.
967 **		mci -- the pointer to fill in.
968 **
969 **	Returns:
970 **		-1 -- if the file was corrupt.
971 **		0 -- otherwise.
972 **
973 **	Warning:
974 **		This code makes the assumption that this data
975 **		will be read in an atomic fashion, and that the data
976 **		was written in an atomic fashion.  Any other functioning
977 **		may lead to some form of insanity.  This should be
978 **		perfectly safe due to underlying stdio buffering.
979 */
980 
981 static int
982 mci_read_persistent(fp, mci)
983 	SM_FILE_T *fp;
984 	register MCI *mci;
985 {
986 	int ver;
987 	register char *p;
988 	int saveLineNumber = LineNumber;
989 	char buf[MAXLINE];
990 
991 	if (fp == NULL)
992 	{
993 		syserr("mci_read_persistent: NULL fp");
994 		/* NOTREACHED */
995 		return -1;
996 	}
997 	if (mci == NULL)
998 	{
999 		syserr("mci_read_persistent: NULL mci");
1000 		/* NOTREACHED */
1001 		return -1;
1002 	}
1003 	if (tTd(56, 93))
1004 	{
1005 		sm_dprintf("mci_read_persistent: fp=%lx, mci=",
1006 			   (unsigned long) fp);
1007 	}
1008 
1009 	SM_FREE(mci->mci_status);
1010 	SM_FREE(mci->mci_rstatus);
1011 
1012 	sm_io_rewind(fp, SM_TIME_DEFAULT);
1013 	ver = -1;
1014 	LineNumber = 0;
1015 	while (sm_io_fgets(fp, SM_TIME_DEFAULT, buf, sizeof(buf)) >= 0)
1016 	{
1017 		LineNumber++;
1018 		p = strchr(buf, '\n');
1019 		if (p != NULL)
1020 			*p = '\0';
1021 		switch (buf[0])
1022 		{
1023 		  case 'V':		/* version stamp */
1024 			ver = atoi(&buf[1]);
1025 			if (ver < 0 || ver > 0)
1026 				syserr("Unknown host status version %d: %d max",
1027 					ver, 0);
1028 			break;
1029 
1030 		  case 'E':		/* UNIX error number */
1031 			mci->mci_errno = atoi(&buf[1]);
1032 			break;
1033 
1034 		  case 'H':		/* DNS error number */
1035 			mci->mci_herrno = atoi(&buf[1]);
1036 			break;
1037 
1038 		  case 'S':		/* UNIX exit status */
1039 			mci->mci_exitstat = atoi(&buf[1]);
1040 			break;
1041 
1042 		  case 'D':		/* DSN status */
1043 			mci->mci_status = newstr(&buf[1]);
1044 			break;
1045 
1046 		  case 'R':		/* SMTP status */
1047 			mci->mci_rstatus = newstr(&buf[1]);
1048 			break;
1049 
1050 		  case 'U':		/* last usage time */
1051 			mci->mci_lastuse = atol(&buf[1]);
1052 			break;
1053 
1054 		  case '.':		/* end of file */
1055 			if (tTd(56, 93))
1056 				mci_dump(sm_debug_file(), mci, false);
1057 			return 0;
1058 
1059 		  default:
1060 			sm_syslog(LOG_CRIT, NOQID,
1061 				  "%s: line %d: Unknown host status line \"%s\"",
1062 				  FileName == NULL ? mci->mci_host : FileName,
1063 				  LineNumber, buf);
1064 			LineNumber = saveLineNumber;
1065 			return -1;
1066 		}
1067 	}
1068 	LineNumber = saveLineNumber;
1069 	if (tTd(56, 93))
1070 		sm_dprintf("incomplete (missing dot for EOF)\n");
1071 	if (ver < 0)
1072 		return -1;
1073 	return 0;
1074 }
1075 /*
1076 **  MCI_STORE_PERSISTENT -- Store persistent MCI information
1077 **
1078 **	Store information about host that is kept
1079 **	in common for all running sendmails.
1080 **
1081 **	Parameters:
1082 **		mci -- the host/connection to store persistent info for.
1083 **
1084 **	Returns:
1085 **		none.
1086 */
1087 
1088 void
1089 mci_store_persistent(mci)
1090 	MCI *mci;
1091 {
1092 	int save_errno = errno;
1093 
1094 	if (mci == NULL)
1095 	{
1096 		if (tTd(56, 1))
1097 			sm_dprintf("mci_store_persistent: NULL mci\n");
1098 		return;
1099 	}
1100 
1101 	if (HostStatDir == NULL || mci->mci_host == NULL)
1102 		return;
1103 
1104 	if (tTd(56, 1))
1105 		sm_dprintf("mci_store_persistent: Storing information for %s\n",
1106 			   mci->mci_host);
1107 
1108 	if (mci->mci_statfile == NULL)
1109 	{
1110 		if (tTd(56, 1))
1111 			sm_dprintf("mci_store_persistent: no statfile\n");
1112 		return;
1113 	}
1114 
1115 	sm_io_rewind(mci->mci_statfile, SM_TIME_DEFAULT);
1116 #if !NOFTRUNCATE
1117 	(void) ftruncate(sm_io_getinfo(mci->mci_statfile, SM_IO_WHAT_FD, NULL),
1118 			 (off_t) 0);
1119 #endif
1120 
1121 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "V0\n");
1122 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "E%d\n",
1123 			     mci->mci_errno);
1124 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "H%d\n",
1125 			     mci->mci_herrno);
1126 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "S%d\n",
1127 			     mci->mci_exitstat);
1128 	if (mci->mci_status != NULL)
1129 		(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT,
1130 				     "D%.80s\n",
1131 				     denlstring(mci->mci_status, true, false));
1132 	if (mci->mci_rstatus != NULL)
1133 		(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT,
1134 				     "R%.80s\n",
1135 				     denlstring(mci->mci_rstatus, true, false));
1136 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "U%ld\n",
1137 			     (long)(mci->mci_lastuse));
1138 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, ".\n");
1139 
1140 	(void) sm_io_flush(mci->mci_statfile, SM_TIME_DEFAULT);
1141 
1142 	errno = save_errno;
1143 	return;
1144 }
1145 /*
1146 **  MCI_TRAVERSE_PERSISTENT -- walk persistent status tree
1147 **
1148 **	Recursively find all the mci host files in `pathname'.  Default to
1149 **		main host status directory if no path is provided.
1150 **	Call (*action)(pathname, host) for each file found.
1151 **
1152 **	Note: all information is collected in a list before it is processed.
1153 **	This may not be the best way to do it, but it seems safest, since
1154 **	the file system would be touched while we are attempting to traverse
1155 **	the directory tree otherwise (during purges).
1156 **
1157 **	Parameters:
1158 **		action -- function to call on each node.  If returns < 0,
1159 **			return immediately.
1160 **		pathname -- root of tree.  If null, use main host status
1161 **			directory.
1162 **
1163 **	Returns:
1164 **		< 0 -- if any action routine returns a negative value, that
1165 **			value is returned.
1166 **		0 -- if we successfully went to completion.
1167 **		> 0 -- return status from action()
1168 */
1169 
1170 int
1171 mci_traverse_persistent(action, pathname)
1172 	int (*action)__P((char *, char *));
1173 	char *pathname;
1174 {
1175 	struct stat statbuf;
1176 	DIR *d;
1177 	int ret;
1178 
1179 	if (pathname == NULL)
1180 		pathname = HostStatDir;
1181 	if (pathname == NULL)
1182 		return -1;
1183 
1184 	if (tTd(56, 1))
1185 		sm_dprintf("mci_traverse: pathname is %s\n", pathname);
1186 
1187 	ret = stat(pathname, &statbuf);
1188 	if (ret < 0)
1189 	{
1190 		if (tTd(56, 2))
1191 			sm_dprintf("mci_traverse: Failed to stat %s: %s\n",
1192 				pathname, sm_errstring(errno));
1193 		return ret;
1194 	}
1195 	if (S_ISDIR(statbuf.st_mode))
1196 	{
1197 		bool leftone, removedone;
1198 		size_t len;
1199 		char *newptr;
1200 		struct dirent *e;
1201 		char newpath[MAXPATHLEN];
1202 #if MAXPATHLEN <= MAXNAMLEN - 3
1203 # ERROR "MAXPATHLEN <= MAXNAMLEN - 3"
1204 #endif
1205 
1206 		if ((d = opendir(pathname)) == NULL)
1207 		{
1208 			if (tTd(56, 2))
1209 				sm_dprintf("mci_traverse: opendir %s: %s\n",
1210 					pathname, sm_errstring(errno));
1211 			return -1;
1212 		}
1213 
1214 		/*
1215 		**  Reserve space for trailing '/', at least one
1216 		**  character, and '\0'
1217 		*/
1218 
1219 		len = sizeof(newpath) - 3;
1220 		if (sm_strlcpy(newpath, pathname, len) >= len)
1221 		{
1222 			int save_errno = errno;
1223 
1224 			if (tTd(56, 2))
1225 				sm_dprintf("mci_traverse: path \"%s\" too long",
1226 					pathname);
1227 			(void) closedir(d);
1228 			errno = save_errno;
1229 			return -1;
1230 		}
1231 		newptr = newpath + strlen(newpath);
1232 		*newptr++ = '/';
1233 		len = sizeof(newpath) - (newptr - newpath);
1234 
1235 		/*
1236 		**  repeat until no file has been removed
1237 		**  this may become ugly when several files "expire"
1238 		**  during these loops, but it's better than doing
1239 		**  a rewinddir() inside the inner loop
1240 		*/
1241 
1242 		do
1243 		{
1244 			leftone = removedone = false;
1245 			while ((e = readdir(d)) != NULL)
1246 			{
1247 				if (e->d_name[0] == '.')
1248 					continue;
1249 
1250 				if (sm_strlcpy(newptr, e->d_name, len) >= len)
1251 				{
1252 					/* Skip truncated copies */
1253 					if (tTd(56, 4))
1254 					{
1255 						*newptr = '\0';
1256 						sm_dprintf("mci_traverse: path \"%s%s\" too long",
1257 							   newpath, e->d_name);
1258 					}
1259 					continue;
1260 				}
1261 
1262 				if (StopRequest)
1263 					stop_sendmail();
1264 				ret = mci_traverse_persistent(action, newpath);
1265 				if (ret < 0)
1266 					break;
1267 				if (ret == 1)
1268 					leftone = true;
1269 				if (!removedone && ret == 0 &&
1270 				    action == mci_purge_persistent)
1271 					removedone = true;
1272 			}
1273 			if (ret < 0)
1274 				break;
1275 
1276 			/*
1277 			**  The following appears to be
1278 			**  necessary during purges, since
1279 			**  we modify the directory structure
1280 			*/
1281 
1282 			if (removedone)
1283 				rewinddir(d);
1284 			if (tTd(56, 40))
1285 				sm_dprintf("mci_traverse: path %s: ret %d removed %d left %d\n",
1286 					pathname, ret, removedone, leftone);
1287 		} while (removedone);
1288 
1289 		/* purge (or whatever) the directory proper */
1290 		if (!leftone)
1291 		{
1292 			*--newptr = '\0';
1293 			ret = (*action)(newpath, NULL);
1294 		}
1295 		(void) closedir(d);
1296 	}
1297 	else if (S_ISREG(statbuf.st_mode))
1298 	{
1299 		char *end = pathname + strlen(pathname) - 1;
1300 		char *start;
1301 		char *scan;
1302 		char host[MAXHOSTNAMELEN];
1303 		char *hostptr = host;
1304 
1305 		/*
1306 		**  Reconstruct the host name from the path to the
1307 		**  persistent information.
1308 		*/
1309 
1310 		do
1311 		{
1312 			if (hostptr != host)
1313 				*(hostptr++) = '.';
1314 			start = end;
1315 			while (start > pathname && *(start - 1) != '/')
1316 				start--;
1317 
1318 			if (*end == '.')
1319 				end--;
1320 
1321 			for (scan = start; scan <= end; scan++)
1322 				*(hostptr++) = *scan;
1323 
1324 			end = start - 2;
1325 		} while (end > pathname && *end == '.');
1326 
1327 		*hostptr = '\0';
1328 
1329 		/*
1330 		**  Do something with the file containing the persistent
1331 		**  information.
1332 		*/
1333 
1334 		ret = (*action)(pathname, host);
1335 	}
1336 
1337 	return ret;
1338 }
1339 /*
1340 **  MCI_PRINT_PERSISTENT -- print persistent info
1341 **
1342 **	Dump the persistent information in the file 'pathname'
1343 **
1344 **	Parameters:
1345 **		pathname -- the pathname to the status file.
1346 **		hostname -- the corresponding host name.
1347 **
1348 **	Returns:
1349 **		0
1350 */
1351 
1352 int
1353 mci_print_persistent(pathname, hostname)
1354 	char *pathname;
1355 	char *hostname;
1356 {
1357 	static bool initflag = false;
1358 	SM_FILE_T *fp;
1359 	int width = Verbose ? 78 : 25;
1360 	bool locked;
1361 	MCI mcib;
1362 
1363 	/* skip directories */
1364 	if (hostname == NULL)
1365 		return 0;
1366 
1367 	if (StopRequest)
1368 		stop_sendmail();
1369 
1370 	if (!initflag)
1371 	{
1372 		initflag = true;
1373 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT,
1374 				     " -------------- Hostname --------------- How long ago ---------Results---------\n");
1375 	}
1376 
1377 	fp = safefopen(pathname, O_RDONLY, FileMode,
1378 		       SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH);
1379 
1380 	if (fp == NULL)
1381 	{
1382 		if (tTd(56, 1))
1383 			sm_dprintf("mci_print_persistent: cannot open %s: %s\n",
1384 				pathname, sm_errstring(errno));
1385 		return 0;
1386 	}
1387 
1388 	FileName = pathname;
1389 	memset(&mcib, '\0', sizeof(mcib));
1390 	if (mci_read_persistent(fp, &mcib) < 0)
1391 	{
1392 		syserr("%s: could not read status file", pathname);
1393 		(void) sm_io_close(fp, SM_TIME_DEFAULT);
1394 		FileName = NULL;
1395 		return 0;
1396 	}
1397 
1398 	locked = !lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), pathname,
1399 			   "", LOCK_SH|LOCK_NB);
1400 	(void) sm_io_close(fp, SM_TIME_DEFAULT);
1401 	FileName = NULL;
1402 
1403 	(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%c%-39s %12s ",
1404 			     locked ? '*' : ' ', hostname,
1405 			     pintvl(curtime() - mcib.mci_lastuse, true));
1406 	if (mcib.mci_rstatus != NULL)
1407 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n", width,
1408 				     mcib.mci_rstatus);
1409 	else if (mcib.mci_exitstat == EX_TEMPFAIL && mcib.mci_errno != 0)
1410 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT,
1411 				     "Deferred: %.*s\n", width - 10,
1412 				     sm_errstring(mcib.mci_errno));
1413 	else if (mcib.mci_exitstat != 0)
1414 	{
1415 		char *exmsg = sm_sysexmsg(mcib.mci_exitstat);
1416 
1417 		if (exmsg == NULL)
1418 		{
1419 			char buf[80];
1420 
1421 			(void) sm_snprintf(buf, sizeof(buf),
1422 				"Unknown mailer error %d",
1423 				mcib.mci_exitstat);
1424 			(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n",
1425 					     width, buf);
1426 		}
1427 		else
1428 			(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n",
1429 					     width, &exmsg[5]);
1430 	}
1431 	else if (mcib.mci_errno == 0)
1432 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "OK\n");
1433 	else
1434 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "OK: %.*s\n",
1435 				     width - 4, sm_errstring(mcib.mci_errno));
1436 
1437 	return 0;
1438 }
1439 /*
1440 **  MCI_PURGE_PERSISTENT -- Remove a persistence status file.
1441 **
1442 **	Parameters:
1443 **		pathname -- path to the status file.
1444 **		hostname -- name of host corresponding to that file.
1445 **			NULL if this is a directory (domain).
1446 **
1447 **	Returns:
1448 **		0 -- ok
1449 **		1 -- file not deleted (too young, incorrect format)
1450 **		< 0 -- some error occurred
1451 */
1452 
1453 int
1454 mci_purge_persistent(pathname, hostname)
1455 	char *pathname;
1456 	char *hostname;
1457 {
1458 	struct stat statbuf;
1459 	char *end = pathname + strlen(pathname) - 1;
1460 	int ret;
1461 
1462 	if (tTd(56, 1))
1463 		sm_dprintf("mci_purge_persistent: purging %s\n", pathname);
1464 
1465 	ret = stat(pathname, &statbuf);
1466 	if (ret < 0)
1467 	{
1468 		if (tTd(56, 2))
1469 			sm_dprintf("mci_purge_persistent: Failed to stat %s: %s\n",
1470 				pathname, sm_errstring(errno));
1471 		return ret;
1472 	}
1473 	if (curtime() - statbuf.st_mtime <= MciInfoTimeout)
1474 		return 1;
1475 	if (hostname != NULL)
1476 	{
1477 		/* remove the file */
1478 		ret = unlink(pathname);
1479 		if (ret < 0)
1480 		{
1481 			if (LogLevel > 8)
1482 				sm_syslog(LOG_ERR, NOQID,
1483 					  "mci_purge_persistent: failed to unlink %s: %s",
1484 					  pathname, sm_errstring(errno));
1485 			if (tTd(56, 2))
1486 				sm_dprintf("mci_purge_persistent: failed to unlink %s: %s\n",
1487 					pathname, sm_errstring(errno));
1488 			return ret;
1489 		}
1490 	}
1491 	else
1492 	{
1493 		/* remove the directory */
1494 		if (*end != '.')
1495 			return 1;
1496 
1497 		if (tTd(56, 1))
1498 			sm_dprintf("mci_purge_persistent: dpurge %s\n", pathname);
1499 
1500 		ret = rmdir(pathname);
1501 		if (ret < 0)
1502 		{
1503 			if (tTd(56, 2))
1504 				sm_dprintf("mci_purge_persistent: rmdir %s: %s\n",
1505 					pathname, sm_errstring(errno));
1506 			return ret;
1507 		}
1508 	}
1509 
1510 	return 0;
1511 }
1512 /*
1513 **  MCI_GENERATE_PERSISTENT_PATH -- generate path from hostname
1514 **
1515 **	Given `host', convert from a.b.c to $HostStatDir/c./b./a,
1516 **	putting the result into `path'.  if `createflag' is set, intervening
1517 **	directories will be created as needed.
1518 **
1519 **	Parameters:
1520 **		host -- host name to convert from.
1521 **		path -- place to store result.
1522 **		pathlen -- length of path buffer.
1523 **		createflag -- if set, create intervening directories as
1524 **			needed.
1525 **
1526 **	Returns:
1527 **		0 -- success
1528 **		-1 -- failure
1529 */
1530 
1531 static int
1532 mci_generate_persistent_path(host, path, pathlen, createflag)
1533 	const char *host;
1534 	char *path;
1535 	int pathlen;
1536 	bool createflag;
1537 {
1538 	char *elem, *p, *x, ch;
1539 	int ret = 0;
1540 	int len;
1541 	char t_host[MAXHOSTNAMELEN];
1542 #if NETINET6
1543 	struct in6_addr in6_addr;
1544 #endif
1545 
1546 	/*
1547 	**  Rationality check the arguments.
1548 	*/
1549 
1550 	if (host == NULL)
1551 	{
1552 		syserr("mci_generate_persistent_path: null host");
1553 		return -1;
1554 	}
1555 	if (path == NULL)
1556 	{
1557 		syserr("mci_generate_persistent_path: null path");
1558 		return -1;
1559 	}
1560 
1561 	if (tTd(56, 80))
1562 		sm_dprintf("mci_generate_persistent_path(%s): ", host);
1563 
1564 	if (*host == '\0' || *host == '.')
1565 		return -1;
1566 
1567 	/* make certain this is not a bracketed host number */
1568 	if (strlen(host) > sizeof(t_host) - 1)
1569 		return -1;
1570 	if (host[0] == '[')
1571 		(void) sm_strlcpy(t_host, host + 1, sizeof(t_host));
1572 	else
1573 		(void) sm_strlcpy(t_host, host, sizeof(t_host));
1574 
1575 	/*
1576 	**  Delete any trailing dots from the hostname.
1577 	**  Leave 'elem' pointing at the \0.
1578 	*/
1579 
1580 	elem = t_host + strlen(t_host);
1581 	while (elem > t_host &&
1582 	       (elem[-1] == '.' || (host[0] == '[' && elem[-1] == ']')))
1583 		*--elem = '\0';
1584 
1585 	/* check for bogus bracketed address */
1586 	if (host[0] == '[')
1587 	{
1588 		bool good = false;
1589 #if NETINET6
1590 		if (anynet_pton(AF_INET6, t_host, &in6_addr) == 1)
1591 			good = true;
1592 #endif
1593 #if NETINET
1594 		if (inet_addr(t_host) != INADDR_NONE)
1595 			good = true;
1596 #endif
1597 		if (!good)
1598 			return -1;
1599 	}
1600 
1601 	/* check for what will be the final length of the path */
1602 	len = strlen(HostStatDir) + 2;
1603 	for (p = (char *) t_host; *p != '\0'; p++)
1604 	{
1605 		if (*p == '.')
1606 			len++;
1607 		len++;
1608 		if (p[0] == '.' && p[1] == '.')
1609 			return -1;
1610 	}
1611 	if (len > pathlen || len < 1)
1612 		return -1;
1613 	(void) sm_strlcpy(path, HostStatDir, pathlen);
1614 	p = path + strlen(path);
1615 	while (elem > t_host)
1616 	{
1617 		if (!path_is_dir(path, createflag))
1618 		{
1619 			ret = -1;
1620 			break;
1621 		}
1622 		elem--;
1623 		while (elem >= t_host && *elem != '.')
1624 			elem--;
1625 		*p++ = '/';
1626 		x = elem + 1;
1627 		while ((ch = *x++) != '\0' && ch != '.')
1628 		{
1629 			if (isascii(ch) && isupper(ch))
1630 				ch = tolower(ch);
1631 			if (ch == '/')
1632 				ch = ':';	/* / -> : */
1633 			*p++ = ch;
1634 		}
1635 		if (elem >= t_host)
1636 			*p++ = '.';
1637 		*p = '\0';
1638 	}
1639 	if (tTd(56, 80))
1640 	{
1641 		if (ret < 0)
1642 			sm_dprintf("FAILURE %d\n", ret);
1643 		else
1644 			sm_dprintf("SUCCESS %s\n", path);
1645 	}
1646 	return ret;
1647 }
1648