xref: /freebsd/contrib/sendmail/src/mci.c (revision 580744621f33383027108364dcadad718df46ffe)
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 /* NETINET || NETINET6 */
21 
22 #include <dirent.h>
23 
24 static int	mci_generate_persistent_path __P((const char *, char *,
25 						  int, bool));
26 static bool	mci_load_persistent __P((MCI *));
27 static void	mci_uncache __P((MCI **, bool));
28 static int	mci_lock_host_statfile __P((MCI *));
29 static int	mci_read_persistent __P((SM_FILE_T *, MCI *));
30 
31 /*
32 **  Mail Connection Information (MCI) Caching Module.
33 **
34 **	There are actually two separate things cached.  The first is
35 **	the set of all open connections -- these are stored in a
36 **	(small) list.  The second is stored in the symbol table; it
37 **	has the overall status for all hosts, whether or not there
38 **	is a connection open currently.
39 **
40 **	There should never be too many connections open (since this
41 **	could flood the socket table), nor should a connection be
42 **	allowed to sit idly for too long.
43 **
44 **	MaxMciCache is the maximum number of open connections that
45 **	will be supported.
46 **
47 **	MciCacheTimeout is the time (in seconds) that a connection
48 **	is permitted to survive without activity.
49 **
50 **	We actually try any cached connections by sending a RSET
51 **	before we use them; if the RSET fails we close down the
52 **	connection and reopen it (see smtpprobe()).
53 **
54 **	The persistent MCI code is donated by Mark Lovell and Paul
55 **	Vixie.  It is based on the long term host status code in KJS
56 **	written by Paul but has been adapted by Mark to fit into the
57 **	MCI structure.
58 */
59 
60 static MCI	**MciCache;		/* the open connection cache */
61 
62 /*
63 **  MCI_CACHE -- enter a connection structure into the open connection cache
64 **
65 **	This may cause something else to be flushed.
66 **
67 **	Parameters:
68 **		mci -- the connection to cache.
69 **
70 **	Returns:
71 **		none.
72 */
73 
74 void
75 mci_cache(mci)
76 	register MCI *mci;
77 {
78 	register MCI **mcislot;
79 
80 	/*
81 	**  Find the best slot.  This may cause expired connections
82 	**  to be closed.
83 	*/
84 
85 	mcislot = mci_scan(mci);
86 	if (mcislot == NULL)
87 	{
88 		/* we don't support caching */
89 		return;
90 	}
91 
92 	if (mci->mci_host == NULL)
93 		return;
94 
95 	/* if this is already cached, we are done */
96 	if (bitset(MCIF_CACHED, mci->mci_flags))
97 		return;
98 
99 	/* otherwise we may have to clear the slot */
100 	if (*mcislot != NULL)
101 		mci_uncache(mcislot, true);
102 
103 	if (tTd(42, 5))
104 		sm_dprintf("mci_cache: caching %p (%s) in slot %d\n",
105 			   mci, mci->mci_host, (int) (mcislot - MciCache));
106 	if (tTd(91, 100))
107 		sm_syslog(LOG_DEBUG, CurEnv->e_id,
108 			  "mci_cache: caching %lx (%.100s) in slot %d",
109 			  (unsigned long) mci, mci->mci_host,
110 			  (int) (mcislot - MciCache));
111 
112 	*mcislot = mci;
113 	mci->mci_flags |= MCIF_CACHED;
114 }
115 /*
116 **  MCI_SCAN -- scan the cache, flush junk, and return best slot
117 **
118 **	Parameters:
119 **		savemci -- never flush this one.  Can be null.
120 **
121 **	Returns:
122 **		The LRU (or empty) slot.
123 */
124 
125 MCI **
126 mci_scan(savemci)
127 	MCI *savemci;
128 {
129 	time_t now;
130 	register MCI **bestmci;
131 	register MCI *mci;
132 	register int i;
133 
134 	if (MaxMciCache <= 0)
135 	{
136 		/* we don't support caching */
137 		return NULL;
138 	}
139 
140 	if (MciCache == NULL)
141 	{
142 		/* first call */
143 		MciCache = (MCI **) sm_pmalloc_x(MaxMciCache * sizeof(*MciCache));
144 		memset((char *) MciCache, '\0', MaxMciCache * sizeof(*MciCache));
145 		return &MciCache[0];
146 	}
147 
148 	now = curtime();
149 	bestmci = &MciCache[0];
150 	for (i = 0; i < MaxMciCache; i++)
151 	{
152 		mci = MciCache[i];
153 		if (mci == NULL || mci->mci_state == MCIS_CLOSED)
154 		{
155 			bestmci = &MciCache[i];
156 			continue;
157 		}
158 		if ((mci->mci_lastuse + MciCacheTimeout <= now ||
159 		     (mci->mci_mailer != NULL &&
160 		      mci->mci_mailer->m_maxdeliveries > 0 &&
161 		      mci->mci_deliveries + 1 >= mci->mci_mailer->m_maxdeliveries))&&
162 		    mci != savemci)
163 		{
164 			/* connection idle too long or too many deliveries */
165 			bestmci = &MciCache[i];
166 
167 			/* close it */
168 			mci_uncache(bestmci, true);
169 			continue;
170 		}
171 		if (*bestmci == NULL)
172 			continue;
173 		if (mci->mci_lastuse < (*bestmci)->mci_lastuse)
174 			bestmci = &MciCache[i];
175 	}
176 	return bestmci;
177 }
178 /*
179 **  MCI_UNCACHE -- remove a connection from a slot.
180 **
181 **	May close a connection.
182 **
183 **	Parameters:
184 **		mcislot -- the slot to empty.
185 **		doquit -- if true, send QUIT protocol on this connection.
186 **			  if false, we are assumed to be in a forked child;
187 **				all we want to do is close the file(s).
188 **
189 **	Returns:
190 **		none.
191 */
192 
193 static void
194 mci_uncache(mcislot, doquit)
195 	register MCI **mcislot;
196 	bool doquit;
197 {
198 	register MCI *mci;
199 	extern ENVELOPE BlankEnvelope;
200 
201 	mci = *mcislot;
202 	if (mci == NULL)
203 		return;
204 	*mcislot = NULL;
205 	if (mci->mci_host == NULL)
206 		return;
207 
208 	mci_unlock_host(mci);
209 
210 	if (tTd(42, 5))
211 		sm_dprintf("mci_uncache: uncaching %p (%s) from slot %d (%d)\n",
212 			   mci, mci->mci_host, (int) (mcislot - MciCache),
213 			   doquit);
214 	if (tTd(91, 100))
215 		sm_syslog(LOG_DEBUG, CurEnv->e_id,
216 			  "mci_uncache: uncaching %lx (%.100s) from slot %d (%d)",
217 			  (unsigned long) mci, mci->mci_host,
218 			  (int) (mcislot - MciCache), doquit);
219 
220 	mci->mci_deliveries = 0;
221 	if (doquit)
222 	{
223 		message("Closing connection to %s", mci->mci_host);
224 
225 		mci->mci_flags &= ~MCIF_CACHED;
226 
227 		/* only uses the envelope to flush the transcript file */
228 		if (mci->mci_state != MCIS_CLOSED)
229 			smtpquit(mci->mci_mailer, mci, &BlankEnvelope);
230 #if XLA
231 		xla_host_end(mci->mci_host);
232 #endif /* XLA */
233 	}
234 	else
235 	{
236 		if (mci->mci_in != NULL)
237 			(void) sm_io_close(mci->mci_in, SM_TIME_DEFAULT);
238 		if (mci->mci_out != NULL)
239 			(void) sm_io_close(mci->mci_out, SM_TIME_DEFAULT);
240 		mci->mci_in = mci->mci_out = NULL;
241 		mci->mci_state = MCIS_CLOSED;
242 		mci->mci_exitstat = EX_OK;
243 		mci->mci_errno = 0;
244 		mci->mci_flags = 0;
245 
246 		mci->mci_retryrcpt = false;
247 		mci->mci_tolist = NULL;
248 #if PIPELINING
249 		mci->mci_okrcpts = 0;
250 #endif /* PIPELINING */
251 	}
252 
253 	SM_FREE_CLR(mci->mci_status);
254 	SM_FREE_CLR(mci->mci_rstatus);
255 	SM_FREE_CLR(mci->mci_heloname);
256 	if (mci->mci_rpool != NULL)
257 	{
258 		sm_rpool_free(mci->mci_rpool);
259 		mci->mci_macro.mac_rpool = NULL;
260 		mci->mci_rpool = NULL;
261 	}
262 }
263 /*
264 **  MCI_FLUSH -- flush the entire cache
265 **
266 **	Parameters:
267 **		doquit -- if true, send QUIT protocol.
268 **			  if false, just close the connection.
269 **		allbut -- but leave this one open.
270 **
271 **	Returns:
272 **		none.
273 */
274 
275 void
276 mci_flush(doquit, allbut)
277 	bool doquit;
278 	MCI *allbut;
279 {
280 	register int i;
281 
282 	if (MciCache == NULL)
283 		return;
284 
285 	for (i = 0; i < MaxMciCache; i++)
286 	{
287 		if (allbut != MciCache[i])
288 			mci_uncache(&MciCache[i], doquit);
289 	}
290 }
291 
292 /*
293 **  MCI_CLR_EXTENSIONS -- clear knowledge about SMTP extensions
294 **
295 **	Parameters:
296 **		mci -- the connection to clear.
297 **
298 **	Returns:
299 **		none.
300 */
301 
302 void
303 mci_clr_extensions(mci)
304 	MCI *mci;
305 {
306 	if (mci == NULL)
307 		return;
308 
309 	mci->mci_flags &= ~MCIF_EXTENS;
310 	mci->mci_maxsize = 0;
311 	mci->mci_min_by = 0;
312 #if SASL
313 	mci->mci_saslcap = NULL;
314 #endif /* SASL */
315 }
316 
317 /*
318 **  MCI_GET -- get information about a particular host
319 **
320 **	Parameters:
321 **		host -- host to look for.
322 **		m -- mailer.
323 **
324 **	Returns:
325 **		mci for this host (might be new).
326 */
327 
328 MCI *
329 mci_get(host, m)
330 	char *host;
331 	MAILER *m;
332 {
333 	register MCI *mci;
334 	register STAB *s;
335 	extern SOCKADDR CurHostAddr;
336 
337 	/* clear CurHostAddr so we don't get a bogus address with this name */
338 	memset(&CurHostAddr, '\0', sizeof(CurHostAddr));
339 
340 	/* clear out any expired connections */
341 	(void) mci_scan(NULL);
342 
343 	if (m->m_mno < 0)
344 		syserr("!negative mno %d (%s)", m->m_mno, m->m_name);
345 
346 	s = stab(host, ST_MCI + m->m_mno, ST_ENTER);
347 	mci = &s->s_mci;
348 
349 	/* initialize per-message data */
350 	mci->mci_retryrcpt = false;
351 	mci->mci_tolist = NULL;
352 #if PIPELINING
353 	mci->mci_okrcpts = 0;
354 #endif /* PIPELINING */
355 	mci->mci_flags &= ~MCIF_NOTSTICKY;
356 
357 	if (mci->mci_rpool == NULL)
358 		mci->mci_rpool = sm_rpool_new_x(NULL);
359 
360 	if (mci->mci_macro.mac_rpool == NULL)
361 		mci->mci_macro.mac_rpool = mci->mci_rpool;
362 
363 	/*
364 	**  We don't need to load the persistent data if we have data
365 	**  already loaded in the cache.
366 	*/
367 
368 	if (mci->mci_host == NULL &&
369 	    (mci->mci_host = s->s_name) != NULL &&
370 	    !mci_load_persistent(mci))
371 	{
372 		if (tTd(42, 2))
373 			sm_dprintf("mci_get(%s %s): lock failed\n",
374 				host, m->m_name);
375 		mci->mci_exitstat = EX_TEMPFAIL;
376 		mci->mci_state = MCIS_CLOSED;
377 		mci->mci_statfile = NULL;
378 		return mci;
379 	}
380 
381 	if (tTd(42, 2))
382 	{
383 		sm_dprintf("mci_get(%s %s): mci_state=%d, _flags=%lx, _exitstat=%d, _errno=%d\n",
384 			host, m->m_name, mci->mci_state, mci->mci_flags,
385 			mci->mci_exitstat, mci->mci_errno);
386 	}
387 
388 	if (mci->mci_state == MCIS_OPEN)
389 	{
390 		/* poke the connection to see if it's still alive */
391 		(void) smtpprobe(mci);
392 
393 		/* reset the stored state in the event of a timeout */
394 		if (mci->mci_state != MCIS_OPEN)
395 		{
396 			mci->mci_errno = 0;
397 			mci->mci_exitstat = EX_OK;
398 			mci->mci_state = MCIS_CLOSED;
399 		}
400 		else
401 		{
402 			/* get peer host address */
403 			/* (this should really be in the mci struct) */
404 			SOCKADDR_LEN_T socklen = sizeof(CurHostAddr);
405 
406 			(void) getpeername(sm_io_getinfo(mci->mci_in,
407 							 SM_IO_WHAT_FD, NULL),
408 				(struct sockaddr *) &CurHostAddr, &socklen);
409 		}
410 	}
411 	if (mci->mci_state == MCIS_CLOSED)
412 	{
413 		time_t now = curtime();
414 
415 		/* if this info is stale, ignore it */
416 		if (mci->mci_lastuse + MciInfoTimeout <= now)
417 		{
418 			mci->mci_lastuse = now;
419 			mci->mci_errno = 0;
420 			mci->mci_exitstat = EX_OK;
421 		}
422 	}
423 
424 	return mci;
425 }
426 
427 /*
428 **  MCI_CLOSE -- (forcefully) close files used for a connection.
429 **	Note: this is a last resort, usually smtpquit() or endmailer()
430 **		should be used to close a connection.
431 **
432 **	Parameters:
433 **		mci -- the connection to close.
434 **		where -- where has this been called?
435 **
436 **	Returns:
437 **		none.
438 */
439 
440 void
441 mci_close(mci, where)
442 	MCI *mci;
443 	char *where;
444 {
445 	bool dumped;
446 
447 	if (mci == NULL)
448 		return;
449 	dumped = false;
450 	if (mci->mci_out != NULL)
451 	{
452 		if (tTd(56, 1))
453 		{
454 			sm_dprintf("mci_close: mci_out!=NULL, where=%s\n",
455 				where);
456 			mci_dump(sm_debug_file(), mci, false);
457 			dumped = true;
458 		}
459 		(void) sm_io_close(mci->mci_out, SM_TIME_DEFAULT);
460 		mci->mci_out = NULL;
461 	}
462 	if (mci->mci_in != NULL)
463 	{
464 		if (tTd(56, 1))
465 		{
466 			sm_dprintf("mci_close: mci_in!=NULL, where=%s\n",
467 				where);
468 			if (!dumped)
469 				mci_dump(sm_debug_file(), mci, false);
470 		}
471 		(void) sm_io_close(mci->mci_in, SM_TIME_DEFAULT);
472 		mci->mci_in = NULL;
473 	}
474 	mci->mci_state = MCIS_CLOSED;
475 }
476 
477 /*
478 **  MCI_NEW -- allocate new MCI structure
479 **
480 **	Parameters:
481 **		rpool -- if non-NULL: allocate from that rpool.
482 **
483 **	Returns:
484 **		mci (new).
485 */
486 
487 MCI *
488 mci_new(rpool)
489 	SM_RPOOL_T *rpool;
490 {
491 	register MCI *mci;
492 
493 	if (rpool == NULL)
494 		mci = (MCI *) sm_malloc_x(sizeof(*mci));
495 	else
496 		mci = (MCI *) sm_rpool_malloc_x(rpool, sizeof(*mci));
497 	memset((char *) mci, '\0', sizeof(*mci));
498 	mci->mci_rpool = sm_rpool_new_x(NULL);
499 	mci->mci_macro.mac_rpool = mci->mci_rpool;
500 	return mci;
501 }
502 /*
503 **  MCI_MATCH -- check connection cache for a particular host
504 **
505 **	Parameters:
506 **		host -- host to look for.
507 **		m -- mailer.
508 **
509 **	Returns:
510 **		true iff open connection exists.
511 */
512 
513 bool
514 mci_match(host, m)
515 	char *host;
516 	MAILER *m;
517 {
518 	register MCI *mci;
519 	register STAB *s;
520 
521 	if (m->m_mno < 0 || m->m_mno > MAXMAILERS)
522 		return false;
523 	s = stab(host, ST_MCI + m->m_mno, ST_FIND);
524 	if (s == NULL)
525 		return false;
526 
527 	mci = &s->s_mci;
528 	return mci->mci_state == MCIS_OPEN;
529 }
530 /*
531 **  MCI_SETSTAT -- set status codes in MCI structure.
532 **
533 **	Parameters:
534 **		mci -- the MCI structure to set.
535 **		xstat -- the exit status code.
536 **		dstat -- the DSN status code.
537 **		rstat -- the SMTP status code.
538 **
539 **	Returns:
540 **		none.
541 */
542 
543 void
544 mci_setstat(mci, xstat, dstat, rstat)
545 	MCI *mci;
546 	int xstat;
547 	char *dstat;
548 	char *rstat;
549 {
550 	/* protocol errors should never be interpreted as sticky */
551 	if (xstat != EX_NOTSTICKY && xstat != EX_PROTOCOL)
552 		mci->mci_exitstat = xstat;
553 
554 	SM_FREE_CLR(mci->mci_status);
555 	if (dstat != NULL)
556 		mci->mci_status = sm_strdup_x(dstat);
557 
558 	SM_FREE_CLR(mci->mci_rstatus);
559 	if (rstat != NULL)
560 		mci->mci_rstatus = sm_strdup_x(rstat);
561 }
562 /*
563 **  MCI_DUMP -- dump the contents of an MCI structure.
564 **
565 **	Parameters:
566 **		fp -- output file pointer
567 **		mci -- the MCI structure to dump.
568 **
569 **	Returns:
570 **		none.
571 **
572 **	Side Effects:
573 **		none.
574 */
575 
576 struct mcifbits
577 {
578 	int	mcif_bit;	/* flag bit */
579 	char	*mcif_name;	/* flag name */
580 };
581 static struct mcifbits	MciFlags[] =
582 {
583 	{ MCIF_VALID,		"VALID"		},
584 	{ MCIF_CACHED,		"CACHED"	},
585 	{ MCIF_ESMTP,		"ESMTP"		},
586 	{ MCIF_EXPN,		"EXPN"		},
587 	{ MCIF_SIZE,		"SIZE"		},
588 	{ MCIF_8BITMIME,	"8BITMIME"	},
589 	{ MCIF_7BIT,		"7BIT"		},
590 	{ MCIF_INHEADER,	"INHEADER"	},
591 	{ MCIF_CVT8TO7,		"CVT8TO7"	},
592 	{ MCIF_DSN,		"DSN"		},
593 	{ MCIF_8BITOK,		"8BITOK"	},
594 	{ MCIF_CVT7TO8,		"CVT7TO8"	},
595 	{ MCIF_INMIME,		"INMIME"	},
596 	{ MCIF_AUTH,		"AUTH"		},
597 	{ MCIF_AUTH2,		"AUTH2"		},
598 	{ MCIF_AUTHACT,		"AUTHACT"	},
599 	{ MCIF_ENHSTAT,		"ENHSTAT"	},
600 	{ MCIF_PIPELINED,	"PIPELINED"	},
601 #if STARTTLS
602 	{ MCIF_TLS,		"TLS"		},
603 	{ MCIF_TLSACT,		"TLSACT"	},
604 #endif /* STARTTLS */
605 	{ MCIF_DLVR_BY,		"DLVR_BY"	},
606 	{ 0,			NULL		}
607 };
608 
609 void
610 mci_dump(fp, mci, logit)
611 	SM_FILE_T *fp;
612 	register MCI *mci;
613 	bool logit;
614 {
615 	register char *p;
616 	char *sep;
617 	char buf[4000];
618 
619 	sep = logit ? " " : "\n\t";
620 	p = buf;
621 	(void) sm_snprintf(p, SPACELEFT(buf, p), "MCI@%p: ", mci);
622 	p += strlen(p);
623 	if (mci == NULL)
624 	{
625 		(void) sm_snprintf(p, SPACELEFT(buf, p), "NULL");
626 		goto printit;
627 	}
628 	(void) sm_snprintf(p, SPACELEFT(buf, p), "flags=%lx", mci->mci_flags);
629 	p += strlen(p);
630 
631 	/*
632 	**  The following check is just for paranoia.  It protects the
633 	**  assignment in the if() clause. If there's not some minimum
634 	**  amount of space we can stop right now. The check will not
635 	**  trigger as long as sizeof(buf)=4000.
636 	*/
637 
638 	if (p >= buf + sizeof(buf) - 4)
639 		goto printit;
640 	if (mci->mci_flags != 0)
641 	{
642 		struct mcifbits *f;
643 
644 		*p++ = '<';	/* protected above */
645 		for (f = MciFlags; f->mcif_bit != 0; f++)
646 		{
647 			if (!bitset(f->mcif_bit, mci->mci_flags))
648 				continue;
649 			(void) sm_strlcpyn(p, SPACELEFT(buf, p), 2,
650 					   f->mcif_name, ",");
651 			p += strlen(p);
652 		}
653 		p[-1] = '>';
654 	}
655 
656 	/* Note: sm_snprintf() takes care of NULL arguments for %s */
657 	(void) sm_snprintf(p, SPACELEFT(buf, p),
658 		",%serrno=%d, herrno=%d, exitstat=%d, state=%d, pid=%d,%s",
659 		sep, mci->mci_errno, mci->mci_herrno,
660 		mci->mci_exitstat, mci->mci_state, (int) mci->mci_pid, sep);
661 	p += strlen(p);
662 	(void) sm_snprintf(p, SPACELEFT(buf, p),
663 		"maxsize=%ld, phase=%s, mailer=%s,%s",
664 		mci->mci_maxsize, mci->mci_phase,
665 		mci->mci_mailer == NULL ? "NULL" : mci->mci_mailer->m_name,
666 		sep);
667 	p += strlen(p);
668 	(void) sm_snprintf(p, SPACELEFT(buf, p),
669 		"status=%s, rstatus=%s,%s",
670 		mci->mci_status, mci->mci_rstatus, sep);
671 	p += strlen(p);
672 	(void) sm_snprintf(p, SPACELEFT(buf, p),
673 		"host=%s, lastuse=%s",
674 		mci->mci_host, ctime(&mci->mci_lastuse));
675 printit:
676 	if (logit)
677 		sm_syslog(LOG_DEBUG, CurEnv->e_id, "%.1000s", buf);
678 	else
679 		(void) sm_io_fprintf(fp, SM_TIME_DEFAULT, "%s\n", buf);
680 }
681 /*
682 **  MCI_DUMP_ALL -- print the entire MCI cache
683 **
684 **	Parameters:
685 **		fp -- output file pointer
686 **		logit -- if set, log the result instead of printing
687 **			to stdout.
688 **
689 **	Returns:
690 **		none.
691 */
692 
693 void
694 mci_dump_all(fp, logit)
695 	SM_FILE_T *fp;
696 	bool logit;
697 {
698 	register int i;
699 
700 	if (MciCache == NULL)
701 		return;
702 
703 	for (i = 0; i < MaxMciCache; i++)
704 		mci_dump(fp, MciCache[i], logit);
705 }
706 /*
707 **  MCI_LOCK_HOST -- Lock host while sending.
708 **
709 **	If we are contacting a host, we'll need to
710 **	update the status information in the host status
711 **	file, and if we want to do that, we ought to have
712 **	locked it. This has the (according to some)
713 **	desirable effect of serializing connectivity with
714 **	remote hosts -- i.e.: one connection to a given
715 **	host at a time.
716 **
717 **	Parameters:
718 **		mci -- containing the host we want to lock.
719 **
720 **	Returns:
721 **		EX_OK	    -- got the lock.
722 **		EX_TEMPFAIL -- didn't get the lock.
723 */
724 
725 int
726 mci_lock_host(mci)
727 	MCI *mci;
728 {
729 	if (mci == NULL)
730 	{
731 		if (tTd(56, 1))
732 			sm_dprintf("mci_lock_host: NULL mci\n");
733 		return EX_OK;
734 	}
735 
736 	if (!SingleThreadDelivery)
737 		return EX_OK;
738 
739 	return mci_lock_host_statfile(mci);
740 }
741 
742 static int
743 mci_lock_host_statfile(mci)
744 	MCI *mci;
745 {
746 	int save_errno = errno;
747 	int retVal = EX_OK;
748 	char fname[MAXPATHLEN];
749 
750 	if (HostStatDir == NULL || mci->mci_host == NULL)
751 		return EX_OK;
752 
753 	if (tTd(56, 2))
754 		sm_dprintf("mci_lock_host: attempting to lock %s\n",
755 			   mci->mci_host);
756 
757 	if (mci_generate_persistent_path(mci->mci_host, fname, sizeof(fname),
758 					 true) < 0)
759 	{
760 		/* of course this should never happen */
761 		if (tTd(56, 2))
762 			sm_dprintf("mci_lock_host: Failed to generate host path for %s\n",
763 				   mci->mci_host);
764 
765 		retVal = EX_TEMPFAIL;
766 		goto cleanup;
767 	}
768 
769 	mci->mci_statfile = safefopen(fname, O_RDWR, FileMode,
770 				      SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH|SFF_CREAT);
771 
772 	if (mci->mci_statfile == NULL)
773 	{
774 		syserr("mci_lock_host: cannot create host lock file %s", fname);
775 		goto cleanup;
776 	}
777 
778 	if (!lockfile(sm_io_getinfo(mci->mci_statfile, SM_IO_WHAT_FD, NULL),
779 		      fname, "", LOCK_EX|LOCK_NB))
780 	{
781 		if (tTd(56, 2))
782 			sm_dprintf("mci_lock_host: couldn't get lock on %s\n",
783 				fname);
784 		(void) sm_io_close(mci->mci_statfile, SM_TIME_DEFAULT);
785 		mci->mci_statfile = NULL;
786 		retVal = EX_TEMPFAIL;
787 		goto cleanup;
788 	}
789 
790 	if (tTd(56, 12) && mci->mci_statfile != NULL)
791 		sm_dprintf("mci_lock_host: Sanity check -- lock is good\n");
792 
793 cleanup:
794 	errno = save_errno;
795 	return retVal;
796 }
797 /*
798 **  MCI_UNLOCK_HOST -- unlock host
799 **
800 **	Clean up the lock on a host, close the file, let
801 **	someone else use it.
802 **
803 **	Parameters:
804 **		mci -- us.
805 **
806 **	Returns:
807 **		nothing.
808 */
809 
810 void
811 mci_unlock_host(mci)
812 	MCI *mci;
813 {
814 	int save_errno = errno;
815 
816 	if (mci == NULL)
817 	{
818 		if (tTd(56, 1))
819 			sm_dprintf("mci_unlock_host: NULL mci\n");
820 		return;
821 	}
822 
823 	if (HostStatDir == NULL || mci->mci_host == NULL)
824 		return;
825 
826 	if (!SingleThreadDelivery && mci_lock_host_statfile(mci) == EX_TEMPFAIL)
827 	{
828 		if (tTd(56, 1))
829 			sm_dprintf("mci_unlock_host: stat file already locked\n");
830 	}
831 	else
832 	{
833 		if (tTd(56, 2))
834 			sm_dprintf("mci_unlock_host: store prior to unlock\n");
835 		mci_store_persistent(mci);
836 	}
837 
838 	if (mci->mci_statfile != NULL)
839 	{
840 		(void) sm_io_close(mci->mci_statfile, SM_TIME_DEFAULT);
841 		mci->mci_statfile = NULL;
842 	}
843 
844 	errno = save_errno;
845 }
846 /*
847 **  MCI_LOAD_PERSISTENT -- load persistent host info
848 **
849 **	Load information about host that is kept
850 **	in common for all running sendmails.
851 **
852 **	Parameters:
853 **		mci -- the host/connection to load persistent info for.
854 **
855 **	Returns:
856 **		true -- lock was successful
857 **		false -- lock failed
858 */
859 
860 static bool
861 mci_load_persistent(mci)
862 	MCI *mci;
863 {
864 	int save_errno = errno;
865 	bool locked = true;
866 	SM_FILE_T *fp;
867 	char fname[MAXPATHLEN];
868 
869 	if (mci == NULL)
870 	{
871 		if (tTd(56, 1))
872 			sm_dprintf("mci_load_persistent: NULL mci\n");
873 		return true;
874 	}
875 
876 	if (IgnoreHostStatus || HostStatDir == NULL || mci->mci_host == NULL)
877 		return true;
878 
879 	/* Already have the persistent information in memory */
880 	if (SingleThreadDelivery && mci->mci_statfile != NULL)
881 		return true;
882 
883 	if (tTd(56, 1))
884 		sm_dprintf("mci_load_persistent: Attempting to load persistent information for %s\n",
885 			   mci->mci_host);
886 
887 	if (mci_generate_persistent_path(mci->mci_host, fname, sizeof(fname),
888 					 false) < 0)
889 	{
890 		/* Not much we can do if the file isn't there... */
891 		if (tTd(56, 1))
892 			sm_dprintf("mci_load_persistent: Couldn't generate host path\n");
893 		goto cleanup;
894 	}
895 
896 	fp = safefopen(fname, O_RDONLY, FileMode,
897 		       SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH);
898 	if (fp == NULL)
899 	{
900 		/* I can't think of any reason this should ever happen */
901 		if (tTd(56, 1))
902 			sm_dprintf("mci_load_persistent: open(%s): %s\n",
903 				fname, sm_errstring(errno));
904 		goto cleanup;
905 	}
906 
907 	FileName = fname;
908 	locked = lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), fname, "",
909 			  LOCK_SH|LOCK_NB);
910 	if (locked)
911 	{
912 		(void) mci_read_persistent(fp, mci);
913 		(void) lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), fname,
914 				"", LOCK_UN);
915 	}
916 	FileName = NULL;
917 	(void) sm_io_close(fp, SM_TIME_DEFAULT);
918 
919 cleanup:
920 	errno = save_errno;
921 	return locked;
922 }
923 /*
924 **  MCI_READ_PERSISTENT -- read persistent host status file
925 **
926 **	Parameters:
927 **		fp -- the file pointer to read.
928 **		mci -- the pointer to fill in.
929 **
930 **	Returns:
931 **		-1 -- if the file was corrupt.
932 **		0 -- otherwise.
933 **
934 **	Warning:
935 **		This code makes the assumption that this data
936 **		will be read in an atomic fashion, and that the data
937 **		was written in an atomic fashion.  Any other functioning
938 **		may lead to some form of insanity.  This should be
939 **		perfectly safe due to underlying stdio buffering.
940 */
941 
942 static int
943 mci_read_persistent(fp, mci)
944 	SM_FILE_T *fp;
945 	register MCI *mci;
946 {
947 	int ver;
948 	register char *p;
949 	int saveLineNumber = LineNumber;
950 	char buf[MAXLINE];
951 
952 	if (fp == NULL)
953 	{
954 		syserr("mci_read_persistent: NULL fp");
955 		/* NOTREACHED */
956 		return -1;
957 	}
958 	if (mci == NULL)
959 	{
960 		syserr("mci_read_persistent: NULL mci");
961 		/* NOTREACHED */
962 		return -1;
963 	}
964 	if (tTd(56, 93))
965 	{
966 		sm_dprintf("mci_read_persistent: fp=%lx, mci=",
967 			   (unsigned long) fp);
968 	}
969 
970 	SM_FREE_CLR(mci->mci_status);
971 	SM_FREE_CLR(mci->mci_rstatus);
972 
973 	sm_io_rewind(fp, SM_TIME_DEFAULT);
974 	ver = -1;
975 	LineNumber = 0;
976 	while (sm_io_fgets(fp, SM_TIME_DEFAULT, buf, sizeof(buf)) >= 0)
977 	{
978 		LineNumber++;
979 		p = strchr(buf, '\n');
980 		if (p != NULL)
981 			*p = '\0';
982 		switch (buf[0])
983 		{
984 		  case 'V':		/* version stamp */
985 			ver = atoi(&buf[1]);
986 			if (ver < 0 || ver > 0)
987 				syserr("Unknown host status version %d: %d max",
988 					ver, 0);
989 			break;
990 
991 		  case 'E':		/* UNIX error number */
992 			mci->mci_errno = atoi(&buf[1]);
993 			break;
994 
995 		  case 'H':		/* DNS error number */
996 			mci->mci_herrno = atoi(&buf[1]);
997 			break;
998 
999 		  case 'S':		/* UNIX exit status */
1000 			mci->mci_exitstat = atoi(&buf[1]);
1001 			break;
1002 
1003 		  case 'D':		/* DSN status */
1004 			mci->mci_status = newstr(&buf[1]);
1005 			break;
1006 
1007 		  case 'R':		/* SMTP status */
1008 			mci->mci_rstatus = newstr(&buf[1]);
1009 			break;
1010 
1011 		  case 'U':		/* last usage time */
1012 			mci->mci_lastuse = atol(&buf[1]);
1013 			break;
1014 
1015 		  case '.':		/* end of file */
1016 			if (tTd(56, 93))
1017 				mci_dump(sm_debug_file(), mci, false);
1018 			return 0;
1019 
1020 		  default:
1021 			sm_syslog(LOG_CRIT, NOQID,
1022 				  "%s: line %d: Unknown host status line \"%s\"",
1023 				  FileName == NULL ? mci->mci_host : FileName,
1024 				  LineNumber, buf);
1025 			LineNumber = saveLineNumber;
1026 			return -1;
1027 		}
1028 	}
1029 	LineNumber = saveLineNumber;
1030 	if (tTd(56, 93))
1031 		sm_dprintf("incomplete (missing dot for EOF)\n");
1032 	if (ver < 0)
1033 		return -1;
1034 	return 0;
1035 }
1036 /*
1037 **  MCI_STORE_PERSISTENT -- Store persistent MCI information
1038 **
1039 **	Store information about host that is kept
1040 **	in common for all running sendmails.
1041 **
1042 **	Parameters:
1043 **		mci -- the host/connection to store persistent info for.
1044 **
1045 **	Returns:
1046 **		none.
1047 */
1048 
1049 void
1050 mci_store_persistent(mci)
1051 	MCI *mci;
1052 {
1053 	int save_errno = errno;
1054 
1055 	if (mci == NULL)
1056 	{
1057 		if (tTd(56, 1))
1058 			sm_dprintf("mci_store_persistent: NULL mci\n");
1059 		return;
1060 	}
1061 
1062 	if (HostStatDir == NULL || mci->mci_host == NULL)
1063 		return;
1064 
1065 	if (tTd(56, 1))
1066 		sm_dprintf("mci_store_persistent: Storing information for %s\n",
1067 			   mci->mci_host);
1068 
1069 	if (mci->mci_statfile == NULL)
1070 	{
1071 		if (tTd(56, 1))
1072 			sm_dprintf("mci_store_persistent: no statfile\n");
1073 		return;
1074 	}
1075 
1076 	sm_io_rewind(mci->mci_statfile, SM_TIME_DEFAULT);
1077 #if !NOFTRUNCATE
1078 	(void) ftruncate(sm_io_getinfo(mci->mci_statfile, SM_IO_WHAT_FD, NULL),
1079 			 (off_t) 0);
1080 #endif /* !NOFTRUNCATE */
1081 
1082 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "V0\n");
1083 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "E%d\n",
1084 			     mci->mci_errno);
1085 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "H%d\n",
1086 			     mci->mci_herrno);
1087 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "S%d\n",
1088 			     mci->mci_exitstat);
1089 	if (mci->mci_status != NULL)
1090 		(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT,
1091 				     "D%.80s\n",
1092 				     denlstring(mci->mci_status, true, false));
1093 	if (mci->mci_rstatus != NULL)
1094 		(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT,
1095 				     "R%.80s\n",
1096 				     denlstring(mci->mci_rstatus, true, false));
1097 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, "U%ld\n",
1098 			     (long)(mci->mci_lastuse));
1099 	(void) sm_io_fprintf(mci->mci_statfile, SM_TIME_DEFAULT, ".\n");
1100 
1101 	(void) sm_io_flush(mci->mci_statfile, SM_TIME_DEFAULT);
1102 
1103 	errno = save_errno;
1104 	return;
1105 }
1106 /*
1107 **  MCI_TRAVERSE_PERSISTENT -- walk persistent status tree
1108 **
1109 **	Recursively find all the mci host files in `pathname'.  Default to
1110 **		main host status directory if no path is provided.
1111 **	Call (*action)(pathname, host) for each file found.
1112 **
1113 **	Note: all information is collected in a list before it is processed.
1114 **	This may not be the best way to do it, but it seems safest, since
1115 **	the file system would be touched while we are attempting to traverse
1116 **	the directory tree otherwise (during purges).
1117 **
1118 **	Parameters:
1119 **		action -- function to call on each node.  If returns < 0,
1120 **			return immediately.
1121 **		pathname -- root of tree.  If null, use main host status
1122 **			directory.
1123 **
1124 **	Returns:
1125 **		< 0 -- if any action routine returns a negative value, that
1126 **			value is returned.
1127 **		0 -- if we successfully went to completion.
1128 **		> 0 -- return status from action()
1129 */
1130 
1131 int
1132 mci_traverse_persistent(action, pathname)
1133 	int (*action)__P((char *, char *));
1134 	char *pathname;
1135 {
1136 	struct stat statbuf;
1137 	DIR *d;
1138 	int ret;
1139 
1140 	if (pathname == NULL)
1141 		pathname = HostStatDir;
1142 	if (pathname == NULL)
1143 		return -1;
1144 
1145 	if (tTd(56, 1))
1146 		sm_dprintf("mci_traverse: pathname is %s\n", pathname);
1147 
1148 	ret = stat(pathname, &statbuf);
1149 	if (ret < 0)
1150 	{
1151 		if (tTd(56, 2))
1152 			sm_dprintf("mci_traverse: Failed to stat %s: %s\n",
1153 				pathname, sm_errstring(errno));
1154 		return ret;
1155 	}
1156 	if (S_ISDIR(statbuf.st_mode))
1157 	{
1158 		bool leftone, removedone;
1159 		size_t len;
1160 		char *newptr;
1161 		struct dirent *e;
1162 		char newpath[MAXPATHLEN];
1163 #if MAXPATHLEN <= MAXNAMLEN - 3
1164  ERROR "MAXPATHLEN <= MAXNAMLEN - 3"
1165 #endif /* MAXPATHLEN  <= MAXNAMLEN - 3 */
1166 
1167 		if ((d = opendir(pathname)) == NULL)
1168 		{
1169 			if (tTd(56, 2))
1170 				sm_dprintf("mci_traverse: opendir %s: %s\n",
1171 					pathname, sm_errstring(errno));
1172 			return -1;
1173 		}
1174 
1175 		/*
1176 		**  Reserve space for trailing '/', at least one
1177 		**  character, and '\0'
1178 		*/
1179 
1180 		len = sizeof(newpath) - 3;
1181 		if (sm_strlcpy(newpath, pathname, len) >= len)
1182 		{
1183 			int save_errno = errno;
1184 
1185 			if (tTd(56, 2))
1186 				sm_dprintf("mci_traverse: path \"%s\" too long",
1187 					pathname);
1188 			(void) closedir(d);
1189 			errno = save_errno;
1190 			return -1;
1191 		}
1192 		newptr = newpath + strlen(newpath);
1193 		*newptr++ = '/';
1194 		len = sizeof(newpath) - (newptr - newpath);
1195 
1196 		/*
1197 		**  repeat until no file has been removed
1198 		**  this may become ugly when several files "expire"
1199 		**  during these loops, but it's better than doing
1200 		**  a rewinddir() inside the inner loop
1201 		*/
1202 
1203 		do
1204 		{
1205 			leftone = removedone = false;
1206 			while ((e = readdir(d)) != NULL)
1207 			{
1208 				if (e->d_name[0] == '.')
1209 					continue;
1210 
1211 				if (sm_strlcpy(newptr, e->d_name, len) >= len)
1212 				{
1213 					/* Skip truncated copies */
1214 					if (tTd(56, 4))
1215 					{
1216 						*newptr = '\0';
1217 						sm_dprintf("mci_traverse: path \"%s%s\" too long",
1218 							   newpath, e->d_name);
1219 					}
1220 					continue;
1221 				}
1222 
1223 				if (StopRequest)
1224 					stop_sendmail();
1225 				ret = mci_traverse_persistent(action, newpath);
1226 				if (ret < 0)
1227 					break;
1228 				if (ret == 1)
1229 					leftone = true;
1230 				if (!removedone && ret == 0 &&
1231 				    action == mci_purge_persistent)
1232 					removedone = true;
1233 			}
1234 			if (ret < 0)
1235 				break;
1236 
1237 			/*
1238 			**  The following appears to be
1239 			**  necessary during purges, since
1240 			**  we modify the directory structure
1241 			*/
1242 
1243 			if (removedone)
1244 				rewinddir(d);
1245 			if (tTd(56, 40))
1246 				sm_dprintf("mci_traverse: path %s: ret %d removed %d left %d\n",
1247 					pathname, ret, removedone, leftone);
1248 		} while (removedone);
1249 
1250 		/* purge (or whatever) the directory proper */
1251 		if (!leftone)
1252 		{
1253 			*--newptr = '\0';
1254 			ret = (*action)(newpath, NULL);
1255 		}
1256 		(void) closedir(d);
1257 	}
1258 	else if (S_ISREG(statbuf.st_mode))
1259 	{
1260 		char *end = pathname + strlen(pathname) - 1;
1261 		char *start;
1262 		char *scan;
1263 		char host[MAXHOSTNAMELEN];
1264 		char *hostptr = host;
1265 
1266 		/*
1267 		**  Reconstruct the host name from the path to the
1268 		**  persistent information.
1269 		*/
1270 
1271 		do
1272 		{
1273 			if (hostptr != host)
1274 				*(hostptr++) = '.';
1275 			start = end;
1276 			while (start > pathname && *(start - 1) != '/')
1277 				start--;
1278 
1279 			if (*end == '.')
1280 				end--;
1281 
1282 			for (scan = start; scan <= end; scan++)
1283 				*(hostptr++) = *scan;
1284 
1285 			end = start - 2;
1286 		} while (end > pathname && *end == '.');
1287 
1288 		*hostptr = '\0';
1289 
1290 		/*
1291 		**  Do something with the file containing the persistent
1292 		**  information.
1293 		*/
1294 
1295 		ret = (*action)(pathname, host);
1296 	}
1297 
1298 	return ret;
1299 }
1300 /*
1301 **  MCI_PRINT_PERSISTENT -- print persistent info
1302 **
1303 **	Dump the persistent information in the file 'pathname'
1304 **
1305 **	Parameters:
1306 **		pathname -- the pathname to the status file.
1307 **		hostname -- the corresponding host name.
1308 **
1309 **	Returns:
1310 **		0
1311 */
1312 
1313 int
1314 mci_print_persistent(pathname, hostname)
1315 	char *pathname;
1316 	char *hostname;
1317 {
1318 	static bool initflag = false;
1319 	SM_FILE_T *fp;
1320 	int width = Verbose ? 78 : 25;
1321 	bool locked;
1322 	MCI mcib;
1323 
1324 	/* skip directories */
1325 	if (hostname == NULL)
1326 		return 0;
1327 
1328 	if (StopRequest)
1329 		stop_sendmail();
1330 
1331 	if (!initflag)
1332 	{
1333 		initflag = true;
1334 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT,
1335 				     " -------------- Hostname --------------- How long ago ---------Results---------\n");
1336 	}
1337 
1338 	fp = safefopen(pathname, O_RDONLY, FileMode,
1339 		       SFF_NOLOCK|SFF_NOLINK|SFF_OPENASROOT|SFF_REGONLY|SFF_SAFEDIRPATH);
1340 
1341 	if (fp == NULL)
1342 	{
1343 		if (tTd(56, 1))
1344 			sm_dprintf("mci_print_persistent: cannot open %s: %s\n",
1345 				pathname, sm_errstring(errno));
1346 		return 0;
1347 	}
1348 
1349 	FileName = pathname;
1350 	memset(&mcib, '\0', sizeof(mcib));
1351 	if (mci_read_persistent(fp, &mcib) < 0)
1352 	{
1353 		syserr("%s: could not read status file", pathname);
1354 		(void) sm_io_close(fp, SM_TIME_DEFAULT);
1355 		FileName = NULL;
1356 		return 0;
1357 	}
1358 
1359 	locked = !lockfile(sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL), pathname,
1360 			   "", LOCK_SH|LOCK_NB);
1361 	(void) sm_io_close(fp, SM_TIME_DEFAULT);
1362 	FileName = NULL;
1363 
1364 	(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%c%-39s %12s ",
1365 			     locked ? '*' : ' ', hostname,
1366 			     pintvl(curtime() - mcib.mci_lastuse, true));
1367 	if (mcib.mci_rstatus != NULL)
1368 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n", width,
1369 				     mcib.mci_rstatus);
1370 	else if (mcib.mci_exitstat == EX_TEMPFAIL && mcib.mci_errno != 0)
1371 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT,
1372 				     "Deferred: %.*s\n", width - 10,
1373 				     sm_errstring(mcib.mci_errno));
1374 	else if (mcib.mci_exitstat != 0)
1375 	{
1376 		char *exmsg = sm_sysexmsg(mcib.mci_exitstat);
1377 
1378 		if (exmsg == NULL)
1379 		{
1380 			char buf[80];
1381 
1382 			(void) sm_snprintf(buf, sizeof(buf),
1383 				"Unknown mailer error %d",
1384 				mcib.mci_exitstat);
1385 			(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n",
1386 					     width, buf);
1387 		}
1388 		else
1389 			(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "%.*s\n",
1390 					     width, &exmsg[5]);
1391 	}
1392 	else if (mcib.mci_errno == 0)
1393 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "OK\n");
1394 	else
1395 		(void) sm_io_fprintf(smioout, SM_TIME_DEFAULT, "OK: %.*s\n",
1396 				     width - 4, sm_errstring(mcib.mci_errno));
1397 
1398 	return 0;
1399 }
1400 /*
1401 **  MCI_PURGE_PERSISTENT -- Remove a persistence status file.
1402 **
1403 **	Parameters:
1404 **		pathname -- path to the status file.
1405 **		hostname -- name of host corresponding to that file.
1406 **			NULL if this is a directory (domain).
1407 **
1408 **	Returns:
1409 **		0 -- ok
1410 **		1 -- file not deleted (too young, incorrect format)
1411 **		< 0 -- some error occurred
1412 */
1413 
1414 int
1415 mci_purge_persistent(pathname, hostname)
1416 	char *pathname;
1417 	char *hostname;
1418 {
1419 	struct stat statbuf;
1420 	char *end = pathname + strlen(pathname) - 1;
1421 	int ret;
1422 
1423 	if (tTd(56, 1))
1424 		sm_dprintf("mci_purge_persistent: purging %s\n", pathname);
1425 
1426 	ret = stat(pathname, &statbuf);
1427 	if (ret < 0)
1428 	{
1429 		if (tTd(56, 2))
1430 			sm_dprintf("mci_purge_persistent: Failed to stat %s: %s\n",
1431 				pathname, sm_errstring(errno));
1432 		return ret;
1433 	}
1434 	if (curtime() - statbuf.st_mtime <= MciInfoTimeout)
1435 		return 1;
1436 	if (hostname != NULL)
1437 	{
1438 		/* remove the file */
1439 		ret = unlink(pathname);
1440 		if (ret < 0)
1441 		{
1442 			if (LogLevel > 8)
1443 				sm_syslog(LOG_ERR, NOQID,
1444 					  "mci_purge_persistent: failed to unlink %s: %s",
1445 					  pathname, sm_errstring(errno));
1446 			if (tTd(56, 2))
1447 				sm_dprintf("mci_purge_persistent: failed to unlink %s: %s\n",
1448 					pathname, sm_errstring(errno));
1449 			return ret;
1450 		}
1451 	}
1452 	else
1453 	{
1454 		/* remove the directory */
1455 		if (*end != '.')
1456 			return 1;
1457 
1458 		if (tTd(56, 1))
1459 			sm_dprintf("mci_purge_persistent: dpurge %s\n", pathname);
1460 
1461 		ret = rmdir(pathname);
1462 		if (ret < 0)
1463 		{
1464 			if (tTd(56, 2))
1465 				sm_dprintf("mci_purge_persistent: rmdir %s: %s\n",
1466 					pathname, sm_errstring(errno));
1467 			return ret;
1468 		}
1469 	}
1470 
1471 	return 0;
1472 }
1473 /*
1474 **  MCI_GENERATE_PERSISTENT_PATH -- generate path from hostname
1475 **
1476 **	Given `host', convert from a.b.c to $HostStatDir/c./b./a,
1477 **	putting the result into `path'.  if `createflag' is set, intervening
1478 **	directories will be created as needed.
1479 **
1480 **	Parameters:
1481 **		host -- host name to convert from.
1482 **		path -- place to store result.
1483 **		pathlen -- length of path buffer.
1484 **		createflag -- if set, create intervening directories as
1485 **			needed.
1486 **
1487 **	Returns:
1488 **		0 -- success
1489 **		-1 -- failure
1490 */
1491 
1492 static int
1493 mci_generate_persistent_path(host, path, pathlen, createflag)
1494 	const char *host;
1495 	char *path;
1496 	int pathlen;
1497 	bool createflag;
1498 {
1499 	char *elem, *p, *x, ch;
1500 	int ret = 0;
1501 	int len;
1502 	char t_host[MAXHOSTNAMELEN];
1503 #if NETINET6
1504 	struct in6_addr in6_addr;
1505 #endif /* NETINET6 */
1506 
1507 	/*
1508 	**  Rationality check the arguments.
1509 	*/
1510 
1511 	if (host == NULL)
1512 	{
1513 		syserr("mci_generate_persistent_path: null host");
1514 		return -1;
1515 	}
1516 	if (path == NULL)
1517 	{
1518 		syserr("mci_generate_persistent_path: null path");
1519 		return -1;
1520 	}
1521 
1522 	if (tTd(56, 80))
1523 		sm_dprintf("mci_generate_persistent_path(%s): ", host);
1524 
1525 	if (*host == '\0' || *host == '.')
1526 		return -1;
1527 
1528 	/* make certain this is not a bracketed host number */
1529 	if (strlen(host) > sizeof(t_host) - 1)
1530 		return -1;
1531 	if (host[0] == '[')
1532 		(void) sm_strlcpy(t_host, host + 1, sizeof(t_host));
1533 	else
1534 		(void) sm_strlcpy(t_host, host, sizeof(t_host));
1535 
1536 	/*
1537 	**  Delete any trailing dots from the hostname.
1538 	**  Leave 'elem' pointing at the \0.
1539 	*/
1540 
1541 	elem = t_host + strlen(t_host);
1542 	while (elem > t_host &&
1543 	       (elem[-1] == '.' || (host[0] == '[' && elem[-1] == ']')))
1544 		*--elem = '\0';
1545 
1546 	/* check for bogus bracketed address */
1547 	if (host[0] == '[')
1548 	{
1549 		bool good = false;
1550 # if NETINET6
1551 		if (anynet_pton(AF_INET6, t_host, &in6_addr) == 1)
1552 			good = true;
1553 # endif /* NETINET6 */
1554 # if NETINET
1555 		if (inet_addr(t_host) != INADDR_NONE)
1556 			good = true;
1557 # endif /* NETINET */
1558 		if (!good)
1559 			return -1;
1560 	}
1561 
1562 	/* check for what will be the final length of the path */
1563 	len = strlen(HostStatDir) + 2;
1564 	for (p = (char *) t_host; *p != '\0'; p++)
1565 	{
1566 		if (*p == '.')
1567 			len++;
1568 		len++;
1569 		if (p[0] == '.' && p[1] == '.')
1570 			return -1;
1571 	}
1572 	if (len > pathlen || len < 1)
1573 		return -1;
1574 	(void) sm_strlcpy(path, HostStatDir, pathlen);
1575 	p = path + strlen(path);
1576 	while (elem > t_host)
1577 	{
1578 		if (!path_is_dir(path, createflag))
1579 		{
1580 			ret = -1;
1581 			break;
1582 		}
1583 		elem--;
1584 		while (elem >= t_host && *elem != '.')
1585 			elem--;
1586 		*p++ = '/';
1587 		x = elem + 1;
1588 		while ((ch = *x++) != '\0' && ch != '.')
1589 		{
1590 			if (isascii(ch) && isupper(ch))
1591 				ch = tolower(ch);
1592 			if (ch == '/')
1593 				ch = ':';	/* / -> : */
1594 			*p++ = ch;
1595 		}
1596 		if (elem >= t_host)
1597 			*p++ = '.';
1598 		*p = '\0';
1599 	}
1600 	if (tTd(56, 80))
1601 	{
1602 		if (ret < 0)
1603 			sm_dprintf("FAILURE %d\n", ret);
1604 		else
1605 			sm_dprintf("SUCCESS %s\n", path);
1606 	}
1607 	return ret;
1608 }
1609