mail.local.c revision 110553 
150472Speter/*
21040Srgrimes * Copyright (c) 1998-2002 Sendmail, Inc. and its suppliers.
31040Srgrimes *	All rights reserved.
4103959Smarkm * Copyright (c) 1990, 1993, 1994
5103959Smarkm *	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 * $FreeBSD: head/contrib/sendmail/mail.local/mail.local.c 110553 2003-02-08 19:25:21Z gshapiro $
12 *
13 */
14
15#include <sm/gen.h>
16
17SM_IDSTR(copyright,
18"@(#) Copyright (c) 1998-2001 Sendmail, Inc. and its suppliers.\n\
19	All rights reserved.\n\
20     Copyright (c) 1990, 1993, 1994\n\
21	The Regents of the University of California.  All rights reserved.\n")
22
23SM_IDSTR(id, "@(#)$Id: mail.local.c,v 8.239 2002/05/24 20:56:32 gshapiro Exp $")
24
25#include <stdlib.h>
26#include <sm/errstring.h>
27#include <sm/io.h>
28#include <sm/limits.h>
29# include <unistd.h>
30# ifdef EX_OK
31#  undef EX_OK		/* unistd.h may have another use for this */
32# endif /* EX_OK */
33#include <sm/mbdb.h>
34#include <sm/sysexits.h>
35
36/*
37**  This is not intended to work on System V derived systems
38**  such as Solaris or HP-UX, since they use a totally different
39**  approach to mailboxes (essentially, they have a set-group-ID program
40**  rather than set-user-ID, and they rely on the ability to "give away"
41**  files to do their work).  IT IS NOT A BUG that this doesn't
42**  work on such architectures.
43*/
44
45
46#include <stdio.h>
47#include <errno.h>
48#include <fcntl.h>
49#include <sys/types.h>
50#include <sys/stat.h>
51#include <time.h>
52#include <stdlib.h>
53# include <sys/socket.h>
54# include <sys/file.h>
55# include <netinet/in.h>
56# include <arpa/nameser.h>
57# include <netdb.h>
58# include <pwd.h>
59
60#include <sm/string.h>
61#include <syslog.h>
62#include <ctype.h>
63
64#include <sm/conf.h>
65#include <sendmail/pathnames.h>
66
67
68/* additional mode for open() */
69# define EXTRA_MODE 0
70
71
72#ifndef LOCKTO_RM
73# define LOCKTO_RM	300	/* timeout for stale lockfile removal */
74#endif /* ! LOCKTO_RM */
75#ifndef LOCKTO_GLOB
76# define LOCKTO_GLOB	400	/* global timeout for lockfile creation */
77#endif /* ! LOCKTO_GLOB */
78
79/* define a realloc() which works for NULL pointers */
80#define REALLOC(ptr, size)	(((ptr) == NULL) ? malloc(size) : realloc(ptr, size))
81
82/*
83**  If you don't have flock, you could try using lockf instead.
84*/
85
86#ifdef LDA_USE_LOCKF
87# define flock(a, b)	lockf(a, b, 0)
88# ifdef LOCK_EX
89#  undef LOCK_EX
90# endif /* LOCK_EX */
91# define LOCK_EX	F_LOCK
92#endif /* LDA_USE_LOCKF */
93
94#ifndef LOCK_EX
95# include <sys/file.h>
96#endif /* ! LOCK_EX */
97
98/*
99**  If you don't have setreuid, and you have saved uids, and you have
100**  a seteuid() call that doesn't try to emulate using setuid(), then
101**  you can try defining LDA_USE_SETEUID.
102*/
103
104#ifdef LDA_USE_SETEUID
105# define setreuid(r, e)		seteuid(e)
106#endif /* LDA_USE_SETEUID */
107
108#ifdef LDA_CONTENTLENGTH
109# define CONTENTLENGTH	1
110#endif /* LDA_CONTENTLENGTH */
111
112#ifndef INADDRSZ
113# define INADDRSZ	4		/* size of an IPv4 address in bytes */
114#endif /* ! INADDRSZ */
115
116#ifdef MAILLOCK
117# include <maillock.h>
118#endif /* MAILLOCK */
119
120#ifndef MAILER_DAEMON
121# define MAILER_DAEMON	"MAILER-DAEMON"
122#endif /* ! MAILER_DAEMON */
123
124#ifdef CONTENTLENGTH
125char	ContentHdr[40] = "Content-Length: ";
126off_t	HeaderLength;
127off_t	BodyLength;
128#endif /* CONTENTLENGTH */
129
130bool	EightBitMime = true;		/* advertise 8BITMIME in LMTP */
131char	ErrBuf[10240];			/* error buffer */
132int	ExitVal = EX_OK;		/* sysexits.h error value. */
133bool	nobiff = false;
134bool	nofsync = false;
135bool	HoldErrs = false;		/* Hold errors in ErrBuf */
136bool	LMTPMode = false;
137bool	BounceQuota = false;		/* permanent error when over quota */
138char	*HomeMailFile = NULL;		/* store mail in homedir */
139
140void	deliver __P((int, char *));
141int	e_to_sys __P((int));
142void	notifybiff __P((char *));
143int	store __P((char *, bool *));
144void	usage __P((void));
145int	lockmbox __P((char *));
146void	unlockmbox __P((void));
147void	mailerr __P((const char *, const char *, ...));
148void	flush_error __P((void));
149
150
151int
152main(argc, argv)
153	int argc;
154	char *argv[];
155{
156	struct passwd *pw;
157	int ch, fd;
158	uid_t uid;
159	char *from;
160	char *mbdbname = "pw";
161	int err;
162	extern char *optarg;
163	extern int optind;
164
165
166	/* make sure we have some open file descriptors */
167	for (fd = 10; fd < 30; fd++)
168		(void) close(fd);
169
170	/* use a reasonable umask */
171	(void) umask(0077);
172
173# ifdef LOG_MAIL
174	openlog("mail.local", 0, LOG_MAIL);
175# else /* LOG_MAIL */
176	openlog("mail.local", 0);
177# endif /* LOG_MAIL */
178
179	from = NULL;
180	while ((ch = getopt(argc, argv, "7BbdD:f:h:r:ls")) != -1)
181	{
182		switch(ch)
183		{
184		  case '7':		/* Do not advertise 8BITMIME */
185			EightBitMime = false;
186			break;
187
188		  case 'B':
189			nobiff = true;
190			break;
191
192		  case 'b':		/* bounce mail when over quota. */
193			BounceQuota = true;
194			break;
195
196		  case 'd':		/* Backward compatible. */
197			break;
198
199		  case 'D':		/* mailbox database type */
200			mbdbname = optarg;
201			break;
202
203		  case 'f':
204		  case 'r':		/* Backward compatible. */
205			if (from != NULL)
206			{
207				mailerr(NULL, "Multiple -f options");
208				usage();
209			}
210			from = optarg;
211			break;
212
213		  case 'h':
214			if (optarg != NULL || *optarg != '\0')
215				HomeMailFile = optarg;
216			else
217			{
218				mailerr(NULL, "-h: missing filename");
219				usage();
220			}
221			break;
222
223		  case 'l':
224			LMTPMode = true;
225			break;
226
227		  case 's':
228			nofsync++;
229			break;
230
231		  case '?':
232		  default:
233			usage();
234		}
235	}
236	argc -= optind;
237	argv += optind;
238
239	/* initialize biff structures */
240	if (!nobiff)
241		notifybiff(NULL);
242
243	err = sm_mbdb_initialize(mbdbname);
244	if (err != EX_OK)
245	{
246		char *errcode = "521";
247
248		if (err == EX_TEMPFAIL)
249			errcode = "421";
250
251		mailerr(errcode, "Can not open mailbox database %s: %s",
252			mbdbname, sm_strexit(err));
253		exit(err);
254	}
255
256	if (LMTPMode)
257	{
258		extern void dolmtp __P((void));
259
260		if (argc > 0)
261		{
262			mailerr("421", "Users should not be specified in command line if LMTP required");
263			exit(EX_TEMPFAIL);
264		}
265
266		dolmtp();
267		/* NOTREACHED */
268		exit(EX_OK);
269	}
270
271	/* Non-LMTP from here on out */
272	if (*argv == '\0')
273		usage();
274
275	/*
276	**  If from not specified, use the name from getlogin() if the
277	**  uid matches, otherwise, use the name from the password file
278	**  corresponding to the uid.
279	*/
280
281	uid = getuid();
282	if (from == NULL && ((from = getlogin()) == NULL ||
283			     (pw = getpwnam(from)) == NULL ||
284			     pw->pw_uid != uid))
285		from = (pw = getpwuid(uid)) != NULL ? pw->pw_name : "???";
286
287	/*
288	**  There is no way to distinguish the error status of one delivery
289	**  from the rest of the deliveries.  So, if we failed hard on one
290	**  or more deliveries, but had no failures on any of the others, we
291	**  return a hard failure.  If we failed temporarily on one or more
292	**  deliveries, we return a temporary failure regardless of the other
293	**  failures.  This results in the delivery being reattempted later
294	**  at the expense of repeated failures and multiple deliveries.
295	*/
296
297	HoldErrs = true;
298	fd = store(from, NULL);
299	HoldErrs = false;
300	if (fd < 0)
301	{
302		flush_error();
303		exit(ExitVal);
304	}
305	for (; *argv != NULL; ++argv)
306		deliver(fd, *argv);
307	exit(ExitVal);
308	/* NOTREACHED */
309	return ExitVal;
310}
311
312char *
313parseaddr(s, rcpt)
314	char *s;
315	bool rcpt;
316{
317	char *p;
318	int l;
319
320	if (*s++ != '<')
321		return NULL;
322
323	p = s;
324
325	/* at-domain-list */
326	while (*p == '@')
327	{
328		p++;
329		while (*p != ',' && *p != ':' && *p != '\0')
330			p++;
331		if (*p == '\0')
332			return NULL;
333
334		/* Skip over , or : */
335		p++;
336	}
337
338	s = p;
339
340	/* local-part */
341	while (*p != '\0' && *p != '@' && *p != '>')
342	{
343		if (*p == '\\')
344		{
345			if (*++p == '\0')
346				return NULL;
347		}
348		else if (*p == '\"')
349		{
350			p++;
351			while (*p != '\0' && *p != '\"')
352			{
353				if (*p == '\\')
354				{
355					if (*++p == '\0')
356						return NULL;
357				}
358				p++;
359			}
360			if (*p == '\0' || *(p + 1) == '\0')
361				return NULL;
362		}
363		/* +detail ? */
364		if (*p == '+' && rcpt)
365			*p = '\0';
366		p++;
367	}
368
369	/* @domain */
370	if (*p == '@')
371	{
372		if (rcpt)
373			*p++ = '\0';
374		while (*p != '\0' && *p != '>')
375			p++;
376	}
377
378	if (*p != '>')
379		return NULL;
380	else
381		*p = '\0';
382	p++;
383
384	if (*p != '\0' && *p != ' ')
385		return NULL;
386
387	if (*s == '\0')
388		s = MAILER_DAEMON;
389
390	l = strlen(s) + 1;
391	if (l < 0)
392		return NULL;
393	p = malloc(l);
394	if (p == NULL)
395	{
396		mailerr("421 4.3.0", "Memory exhausted");
397		exit(EX_TEMPFAIL);
398	}
399
400	(void) sm_strlcpy(p, s, l);
401	return p;
402}
403
404char *
405process_recipient(addr)
406	char *addr;
407{
408	SM_MBDB_T user;
409
410	switch (sm_mbdb_lookup(addr, &user))
411	{
412	  case EX_OK:
413		return NULL;
414
415	  case EX_NOUSER:
416		return "550 5.1.1 User unknown";
417
418	  case EX_TEMPFAIL:
419		return "451 4.3.0 User database failure; retry later";
420
421	  default:
422		return "550 5.3.0 User database failure";
423	}
424}
425
426#define RCPT_GROW	30
427
428void
429dolmtp()
430{
431	char *return_path = NULL;
432	char **rcpt_addr = NULL;
433	int rcpt_num = 0;
434	int rcpt_alloc = 0;
435	bool gotlhlo = false;
436	char *err;
437	int msgfd;
438	char *p;
439	int i;
440	char myhostname[1024];
441	char buf[4096];
442
443	memset(myhostname, '\0', sizeof myhostname);
444	(void) gethostname(myhostname, sizeof myhostname - 1);
445	if (myhostname[0] == '\0')
446		sm_strlcpy(myhostname, "localhost", sizeof myhostname);
447
448	printf("220 %s LMTP ready\r\n", myhostname);
449	for (;;)
450	{
451		(void) fflush(stdout);
452		if (fgets(buf, sizeof(buf) - 1, stdin) == NULL)
453			exit(EX_OK);
454		p = buf + strlen(buf) - 1;
455		if (p >= buf && *p == '\n')
456			*p-- = '\0';
457		if (p >= buf && *p == '\r')
458			*p-- = '\0';
459
460		switch (buf[0])
461		{
462		  case 'd':
463		  case 'D':
464			if (sm_strcasecmp(buf, "data") == 0)
465			{
466				bool inbody = false;
467
468				if (rcpt_num == 0)
469				{
470					mailerr("503 5.5.1", "No recipients");
471					continue;
472				}
473				HoldErrs = true;
474				msgfd = store(return_path, &inbody);
475				HoldErrs = false;
476				if (msgfd < 0 && !inbody)
477				{
478					flush_error();
479					continue;
480				}
481
482				for (i = 0; i < rcpt_num; i++)
483				{
484					if (msgfd < 0)
485					{
486						/* print error for rcpt */
487						flush_error();
488						continue;
489					}
490					p = strchr(rcpt_addr[i], '+');
491					if (p != NULL)
492						*p = '\0';
493					deliver(msgfd, rcpt_addr[i]);
494				}
495				if (msgfd >= 0)
496					(void) close(msgfd);
497				goto rset;
498			}
499			goto syntaxerr;
500			/* NOTREACHED */
501			break;
502
503		  case 'l':
504		  case 'L':
505			if (sm_strncasecmp(buf, "lhlo ", 5) == 0)
506			{
507				/* check for duplicate per RFC 1651 4.2 */
508				if (gotlhlo)
509				{
510					mailerr("503", "%s Duplicate LHLO",
511					       myhostname);
512					continue;
513				}
514				gotlhlo = true;
515				printf("250-%s\r\n", myhostname);
516				if (EightBitMime)
517					printf("250-8BITMIME\r\n");
518				printf("250-ENHANCEDSTATUSCODES\r\n");
519				printf("250 PIPELINING\r\n");
520				continue;
521			}
522			goto syntaxerr;
523			/* NOTREACHED */
524			break;
525
526		  case 'm':
527		  case 'M':
528			if (sm_strncasecmp(buf, "mail ", 5) == 0)
529			{
530				if (return_path != NULL)
531				{
532					mailerr("503 5.5.1",
533						"Nested MAIL command");
534					continue;
535				}
536				if (sm_strncasecmp(buf + 5, "from:", 5) != 0 ||
537				    ((return_path = parseaddr(buf + 10,
538							      false)) == NULL))
539				{
540					mailerr("501 5.5.4",
541						"Syntax error in parameters");
542					continue;
543				}
544				printf("250 2.5.0 Ok\r\n");
545				continue;
546			}
547			goto syntaxerr;
548			/* NOTREACHED */
549			break;
550
551		  case 'n':
552		  case 'N':
553			if (sm_strcasecmp(buf, "noop") == 0)
554			{
555				printf("250 2.0.0 Ok\r\n");
556				continue;
557			}
558			goto syntaxerr;
559			/* NOTREACHED */
560			break;
561
562		  case 'q':
563		  case 'Q':
564			if (sm_strcasecmp(buf, "quit") == 0)
565			{
566				printf("221 2.0.0 Bye\r\n");
567				exit(EX_OK);
568			}
569			goto syntaxerr;
570			/* NOTREACHED */
571			break;
572
573		  case 'r':
574		  case 'R':
575			if (sm_strncasecmp(buf, "rcpt ", 5) == 0)
576			{
577				if (return_path == NULL)
578				{
579					mailerr("503 5.5.1",
580						"Need MAIL command");
581					continue;
582				}
583				if (rcpt_num >= rcpt_alloc)
584				{
585					rcpt_alloc += RCPT_GROW;
586					rcpt_addr = (char **)
587						REALLOC((char *) rcpt_addr,
588							rcpt_alloc *
589							sizeof(char **));
590					if (rcpt_addr == NULL)
591					{
592						mailerr("421 4.3.0",
593							"Memory exhausted");
594						exit(EX_TEMPFAIL);
595					}
596				}
597				if (sm_strncasecmp(buf + 5, "to:", 3) != 0 ||
598				    ((rcpt_addr[rcpt_num] = parseaddr(buf + 8,
599								      true)) == NULL))
600				{
601					mailerr("501 5.5.4",
602						"Syntax error in parameters");
603					continue;
604				}
605				err = process_recipient(rcpt_addr[rcpt_num]);
606				if (err != NULL)
607				{
608					mailerr(NULL, "%s", err);
609					continue;
610				}
611				rcpt_num++;
612				printf("250 2.1.5 Ok\r\n");
613				continue;
614			}
615			else if (sm_strcasecmp(buf, "rset") == 0)
616			{
617				printf("250 2.0.0 Ok\r\n");
618
619rset:
620				while (rcpt_num > 0)
621					free(rcpt_addr[--rcpt_num]);
622				if (return_path != NULL)
623					free(return_path);
624				return_path = NULL;
625				continue;
626			}
627			goto syntaxerr;
628			/* NOTREACHED */
629			break;
630
631		  case 'v':
632		  case 'V':
633			if (sm_strncasecmp(buf, "vrfy ", 5) == 0)
634			{
635				printf("252 2.3.3 Try RCPT to attempt delivery\r\n");
636				continue;
637			}
638			goto syntaxerr;
639			/* NOTREACHED */
640			break;
641
642		  default:
643  syntaxerr:
644			mailerr("500 5.5.2", "Syntax error");
645			continue;
646			/* NOTREACHED */
647			break;
648		}
649	}
650}
651
652int
653store(from, inbody)
654	char *from;
655	bool *inbody;
656{
657	FILE *fp = NULL;
658	time_t tval;
659	bool eline;		/* previous line was empty */
660	bool fullline = true;	/* current line is terminated */
661	bool prevfl;		/* previous line was terminated */
662	char line[2048];
663	int fd;
664	char tmpbuf[sizeof _PATH_LOCTMP + 1];
665
666	if (inbody != NULL)
667		*inbody = false;
668
669	(void) umask(0077);
670	(void) sm_strlcpy(tmpbuf, _PATH_LOCTMP, sizeof tmpbuf);
671	if ((fd = mkstemp(tmpbuf)) < 0 || (fp = fdopen(fd, "w+")) == NULL)
672	{
673		mailerr("451 4.3.0", "Unable to open temporary file");
674		return -1;
675	}
676	(void) unlink(tmpbuf);
677
678	if (LMTPMode)
679	{
680		printf("354 Go ahead\r\n");
681		(void) fflush(stdout);
682	}
683	if (inbody != NULL)
684		*inbody = true;
685
686	(void) time(&tval);
687	(void) fprintf(fp, "From %s %s", from, ctime(&tval));
688
689#ifdef CONTENTLENGTH
690	HeaderLength = 0;
691	BodyLength = -1;
692#endif /* CONTENTLENGTH */
693
694	line[0] = '\0';
695	eline = true;
696	while (fgets(line, sizeof(line), stdin) != (char *) NULL)
697	{
698		size_t line_len = 0;
699		int peek;
700
701		prevfl = fullline;	/* preserve state of previous line */
702		while (line[line_len] != '\n' && line_len < sizeof(line) - 2)
703			line_len++;
704		line_len++;
705
706		/* Check for dot-stuffing */
707		if (prevfl && LMTPMode && line[0] == '.')
708		{
709			if (line[1] == '\n' ||
710			    (line[1] == '\r' && line[2] == '\n'))
711				goto lmtpdot;
712			memcpy(line, line + 1, line_len);
713			line_len--;
714		}
715
716		/* Check to see if we have the full line from fgets() */
717		fullline = false;
718		if (line_len > 0)
719		{
720			if (line[line_len - 1] == '\n')
721			{
722				if (line_len >= 2 &&
723				    line[line_len - 2] == '\r')
724				{
725					line[line_len - 2] = '\n';
726					line[line_len - 1] = '\0';
727					line_len--;
728				}
729				fullline = true;
730			}
731			else if (line[line_len - 1] == '\r')
732			{
733				/* Did we just miss the CRLF? */
734				peek = fgetc(stdin);
735				if (peek == '\n')
736				{
737					line[line_len - 1] = '\n';
738					fullline = true;
739				}
740				else
741					(void) ungetc(peek, stdin);
742			}
743		}
744		else
745			fullline = true;
746
747#ifdef CONTENTLENGTH
748		if (prevfl && line[0] == '\n' && HeaderLength == 0)
749		{
750			eline = false;
751			if (fp != NULL)
752				HeaderLength = ftell(fp);
753			if (HeaderLength <= 0)
754			{
755				/*
756				**  shouldn't happen, unless ftell() is
757				**  badly broken
758				*/
759
760				HeaderLength = -1;
761			}
762		}
763#else /* CONTENTLENGTH */
764		if (prevfl && line[0] == '\n')
765			eline = true;
766#endif /* CONTENTLENGTH */
767		else
768		{
769			if (eline && line[0] == 'F' &&
770			    fp != NULL &&
771			    !memcmp(line, "From ", 5))
772				(void) putc('>', fp);
773			eline = false;
774#ifdef CONTENTLENGTH
775			/* discard existing "Content-Length:" headers */
776			if (prevfl && HeaderLength == 0 &&
777			    (line[0] == 'C' || line[0] == 'c') &&
778			    sm_strncasecmp(line, ContentHdr, 15) == 0)
779			{
780				/*
781				**  be paranoid: clear the line
782				**  so no "wrong matches" may occur later
783				*/
784				line[0] = '\0';
785				continue;
786			}
787#endif /* CONTENTLENGTH */
788
789		}
790		if (fp != NULL)
791		{
792			(void) fwrite(line, sizeof(char), line_len, fp);
793			if (ferror(fp))
794			{
795				mailerr("451 4.3.0",
796					"Temporary file write error");
797				(void) fclose(fp);
798				fp = NULL;
799				continue;
800			}
801		}
802	}
803
804	/* check if an error occurred */
805	if (fp == NULL)
806		return -1;
807
808	if (LMTPMode)
809	{
810		/* Got a premature EOF -- toss message and exit */
811		exit(EX_OK);
812	}
813
814	/* If message not newline terminated, need an extra. */
815	if (fp != NULL && strchr(line, '\n') == NULL)
816		(void) putc('\n', fp);
817
818  lmtpdot:
819
820#ifdef CONTENTLENGTH
821	if (fp != NULL)
822		BodyLength = ftell(fp);
823	if (HeaderLength == 0 && BodyLength > 0)	/* empty body */
824	{
825		HeaderLength = BodyLength;
826		BodyLength = 0;
827	}
828	else
829		BodyLength = BodyLength - HeaderLength - 1 ;
830
831	if (HeaderLength > 0 && BodyLength >= 0)
832	{
833		(void) sm_snprintf(line, sizeof line, "%lld\n",
834				   (LONGLONG_T) BodyLength);
835		(void) sm_strlcpy(&ContentHdr[16], line,
836				  sizeof(ContentHdr) - 16);
837	}
838	else
839		BodyLength = -1;	/* Something is wrong here */
840#endif /* CONTENTLENGTH */
841
842	/* Output a newline; note, empty messages are allowed. */
843	if (fp != NULL)
844		(void) putc('\n', fp);
845
846	if (fp == NULL || fflush(fp) == EOF || ferror(fp) != 0)
847	{
848		mailerr("451 4.3.0", "Temporary file write error");
849		if (fp != NULL)
850			(void) fclose(fp);
851		return -1;
852	}
853	return fd;
854}
855
856void
857deliver(fd, name)
858	int fd;
859	char *name;
860{
861	struct stat fsb;
862	struct stat sb;
863	char path[MAXPATHLEN];
864	int mbfd = -1, nr = 0, nw, off;
865	int exitval;
866	char *p;
867	char *errcode;
868	off_t curoff;
869#ifdef CONTENTLENGTH
870	off_t headerbytes;
871	int readamount;
872#endif /* CONTENTLENGTH */
873	char biffmsg[100], buf[8 * 1024];
874	SM_MBDB_T user;
875
876	/*
877	**  Disallow delivery to unknown names -- special mailboxes can be
878	**  handled in the sendmail aliases file.
879	*/
880
881	exitval = sm_mbdb_lookup(name, &user);
882	switch (exitval)
883	{
884	  case EX_OK:
885		break;
886
887	  case EX_NOUSER:
888		exitval = EX_UNAVAILABLE;
889		mailerr("550 5.1.1", "%s: User unknown", name);
890		break;
891
892	  case EX_TEMPFAIL:
893		mailerr("451 4.3.0", "%s: User database failure; retry later",
894			name);
895		break;
896
897	  default:
898		exitval = EX_UNAVAILABLE;
899		mailerr("550 5.3.0", "%s: User database failure", name);
900		break;
901	}
902
903	if (exitval != EX_OK)
904	{
905		if (ExitVal != EX_TEMPFAIL)
906			ExitVal = exitval;
907		return;
908	}
909
910	endpwent();
911
912	/*
913	**  Keep name reasonably short to avoid buffer overruns.
914	**	This isn't necessary on BSD because of the proper
915	**	definition of snprintf(), but it can cause problems
916	**	on other systems.
917	**  Also, clear out any bogus characters.
918	*/
919
920	if (strlen(name) > 40)
921		name[40] = '\0';
922	for (p = name; *p != '\0'; p++)
923	{
924		if (!isascii(*p))
925			*p &= 0x7f;
926		else if (!isprint(*p))
927			*p = '.';
928	}
929
930
931	if (HomeMailFile == NULL)
932	{
933		if (sm_snprintf(path, sizeof(path), "%s/%s",
934				_PATH_MAILDIR, name) >= sizeof(path))
935		{
936			exitval = EX_UNAVAILABLE;
937			mailerr("550 5.1.1", "%s: Invalid mailbox path", name);
938			return;
939		}
940	}
941	else if (*user.mbdb_homedir == '\0')
942	{
943		exitval = EX_UNAVAILABLE;
944		mailerr("550 5.1.1", "%s: User missing home directory", name);
945		return;
946	}
947	else if (sm_snprintf(path, sizeof(path), "%s/%s",
948			     user.mbdb_homedir, HomeMailFile) >= sizeof(path))
949	{
950		exitval = EX_UNAVAILABLE;
951		mailerr("550 5.1.1", "%s: Invalid mailbox path", name);
952		return;
953	}
954
955
956	/*
957	**  If the mailbox is linked or a symlink, fail.  There's an obvious
958	**  race here, that the file was replaced with a symbolic link after
959	**  the lstat returned, but before the open.  We attempt to detect
960	**  this by comparing the original stat information and information
961	**  returned by an fstat of the file descriptor returned by the open.
962	**
963	**  NB: this is a symptom of a larger problem, that the mail spooling
964	**  directory is writeable by the wrong users.  If that directory is
965	**  writeable, system security is compromised for other reasons, and
966	**  it cannot be fixed here.
967	**
968	**  If we created the mailbox, set the owner/group.  If that fails,
969	**  just return.  Another process may have already opened it, so we
970	**  can't unlink it.  Historically, binmail set the owner/group at
971	**  each mail delivery.  We no longer do this, assuming that if the
972	**  ownership or permissions were changed there was a reason.
973	**
974	**  XXX
975	**  open(2) should support flock'ing the file.
976	*/
977
978tryagain:
979#ifdef MAILLOCK
980	p = name;
981#else /* MAILLOCK */
982	p = path;
983#endif /* MAILLOCK */
984	if ((off = lockmbox(p)) != 0)
985	{
986		if (off == EX_TEMPFAIL || e_to_sys(off) == EX_TEMPFAIL)
987		{
988			ExitVal = EX_TEMPFAIL;
989			errcode = "451 4.3.0";
990		}
991		else
992			errcode = "551 5.3.0";
993
994		mailerr(errcode, "lockmailbox %s failed; error code %d %s",
995			p, off, errno > 0 ? sm_errstring(errno) : "");
996		return;
997	}
998
999	if (lstat(path, &sb) < 0)
1000	{
1001		int save_errno;
1002		int mode = S_IRUSR|S_IWUSR;
1003		gid_t gid = user.mbdb_gid;
1004
1005#ifdef MAILGID
1006		(void) umask(0007);
1007		gid = MAILGID;
1008		mode |= S_IRGRP|S_IWGRP;
1009#endif /* MAILGID */
1010
1011		mbfd = open(path, O_APPEND|O_CREAT|O_EXCL|O_WRONLY|EXTRA_MODE,
1012			    mode);
1013		save_errno = errno;
1014
1015		if (lstat(path, &sb) < 0)
1016		{
1017			ExitVal = EX_CANTCREAT;
1018			mailerr("550 5.2.0",
1019				"%s: lstat: file changed after open", path);
1020			goto err1;
1021		}
1022		if (mbfd < 0)
1023		{
1024			if (save_errno == EEXIST)
1025				goto tryagain;
1026
1027			/* open failed, don't try again */
1028			mailerr("450 4.2.0", "%s: %s", path,
1029				sm_errstring(save_errno));
1030			goto err0;
1031		}
1032		else if (fchown(mbfd, user.mbdb_uid, gid) < 0)
1033		{
1034			mailerr("451 4.3.0", "chown %u.%u: %s",
1035				user.mbdb_uid, gid, name);
1036			goto err1;
1037		}
1038		else
1039		{
1040			/*
1041			**  open() was successful, now close it so can
1042			**  be opened as the right owner again.
1043			**  Paranoia: reset mbdf since the file descriptor
1044			**  is no longer valid; better safe than sorry.
1045			*/
1046
1047			sb.st_uid = user.mbdb_uid;
1048			(void) close(mbfd);
1049			mbfd = -1;
1050		}
1051	}
1052	else if (sb.st_nlink != 1 || !S_ISREG(sb.st_mode))
1053	{
1054		mailerr("550 5.2.0", "%s: irregular file", path);
1055		goto err0;
1056	}
1057	else if (sb.st_uid != user.mbdb_uid)
1058	{
1059		ExitVal = EX_CANTCREAT;
1060		mailerr("550 5.2.0", "%s: wrong ownership (%d)",
1061			path, (int) sb.st_uid);
1062		goto err0;
1063	}
1064
1065	/* change UID for quota checks */
1066	if (setreuid(0, user.mbdb_uid) < 0)
1067	{
1068		mailerr("450 4.2.0", "setreuid(0, %d): %s (r=%d, e=%d)",
1069			(int) user.mbdb_uid, sm_errstring(errno),
1070			(int) getuid(), (int) geteuid());
1071		goto err1;
1072	}
1073#ifdef DEBUG
1074	fprintf(stderr, "new euid = %d\n", (int) geteuid());
1075#endif /* DEBUG */
1076	mbfd = open(path, O_APPEND|O_WRONLY|EXTRA_MODE, 0);
1077	if (mbfd < 0)
1078	{
1079		mailerr("450 4.2.0", "%s: %s", path, sm_errstring(errno));
1080		goto err0;
1081	}
1082	else if (fstat(mbfd, &fsb) < 0 ||
1083		 fsb.st_nlink != 1 ||
1084		 sb.st_nlink != 1 ||
1085		 !S_ISREG(fsb.st_mode) ||
1086		 sb.st_dev != fsb.st_dev ||
1087		 sb.st_ino != fsb.st_ino ||
1088# if HAS_ST_GEN && 0		/* AFS returns random values for st_gen */
1089		 sb.st_gen != fsb.st_gen ||
1090# endif /* HAS_ST_GEN && 0 */
1091		 sb.st_uid != fsb.st_uid)
1092	{
1093		ExitVal = EX_TEMPFAIL;
1094		mailerr("550 5.2.0", "%s: fstat: file changed after open",
1095			path);
1096		goto err1;
1097	}
1098
1099#if 0
1100	/*
1101	**  This code could be reused if we decide to add a
1102	**  per-user quota field to the sm_mbdb interface.
1103	*/
1104
1105	/*
1106	**  Fail if the user has a quota specified, and delivery of this
1107	**  message would exceed that quota.  We bounce such failures using
1108	**  EX_UNAVAILABLE, unless there were internal problems, since
1109	**  storing immense messages for later retries can cause queueing
1110	**  issues.
1111	*/
1112
1113	if (ui.quota > 0)
1114	{
1115		struct stat dsb;
1116
1117		if (fstat(fd, &dsb) < 0)
1118		{
1119			ExitVal = EX_TEMPFAIL;
1120			mailerr("451 4.3.0",
1121				"%s: fstat: can't stat temporary storage: %s",
1122				ui.mailspool, sm_errstring(errno));
1123			goto err1;
1124		}
1125
1126		if (dsb.st_size + sb.st_size + 1 > ui.quota)
1127		{
1128			ExitVal = EX_UNAVAILABLE;
1129			mailerr("551 5.2.2",
1130				"%s: Mailbox full or quota exceeded",
1131				ui.mailspool);
1132			goto err1;
1133		}
1134	}
1135#endif /* 0 */
1136
1137	/* Wait until we can get a lock on the file. */
1138	if (flock(mbfd, LOCK_EX) < 0)
1139	{
1140		mailerr("450 4.2.0", "%s: %s", path, sm_errstring(errno));
1141		goto err1;
1142	}
1143
1144	/* Get the starting offset of the new message for biff. */
1145	curoff = lseek(mbfd, (off_t) 0, SEEK_END);
1146
1147	if (!nobiff)
1148	{
1149		(void) sm_snprintf(biffmsg, sizeof(biffmsg), "%s@%lld\n",
1150				   name, (LONGLONG_T) curoff);
1151	}
1152
1153	/* Copy the message into the file. */
1154	if (lseek(fd, (off_t) 0, SEEK_SET) == (off_t) -1)
1155	{
1156		mailerr("450 4.2.0", "Temporary file: %s",
1157			sm_errstring(errno));
1158		goto err1;
1159	}
1160#ifdef DEBUG
1161	fprintf(stderr, "before writing: euid = %d\n", (int) geteuid());
1162#endif /* DEBUG */
1163#ifdef CONTENTLENGTH
1164	headerbytes = (BodyLength >= 0) ? HeaderLength : -1 ;
1165	for (;;)
1166	{
1167		if (headerbytes == 0)
1168		{
1169			(void) sm_snprintf(buf, sizeof buf, "%s", ContentHdr);
1170			nr = strlen(buf);
1171			headerbytes = -1;
1172			readamount = 0;
1173		}
1174		else if (headerbytes > sizeof(buf) || headerbytes < 0)
1175			readamount = sizeof(buf);
1176		else
1177			readamount = headerbytes;
1178		if (readamount != 0)
1179			nr = read(fd, buf, readamount);
1180		if (nr <= 0)
1181			break;
1182		if (headerbytes > 0)
1183			headerbytes -= nr ;
1184
1185#else /* CONTENTLENGTH */
1186	while ((nr = read(fd, buf, sizeof(buf))) > 0)
1187	{
1188#endif /* CONTENTLENGTH */
1189		for (off = 0; off < nr; off += nw)
1190		{
1191			if ((nw = write(mbfd, buf + off, nr - off)) < 0)
1192			{
1193				errcode = "450 4.2.0";
1194#ifdef EDQUOT
1195				if (errno == EDQUOT && BounceQuota)
1196					errcode = "552 5.2.2";
1197#endif /* EDQUOT */
1198				mailerr(errcode, "%s: %s",
1199					path, sm_errstring(errno));
1200				goto err3;
1201			}
1202		}
1203	}
1204	if (nr < 0)
1205	{
1206		mailerr("450 4.2.0", "Temporary file: %s",
1207			sm_errstring(errno));
1208		goto err3;
1209	}
1210
1211	/* Flush to disk, don't wait for update. */
1212	if (!nofsync && fsync(mbfd) < 0)
1213	{
1214		mailerr("450 4.2.0", "%s: %s", path, sm_errstring(errno));
1215err3:
1216		(void) setreuid(0, 0);
1217#ifdef DEBUG
1218		fprintf(stderr, "reset euid = %d\n", (int) geteuid());
1219#endif /* DEBUG */
1220		(void) ftruncate(mbfd, curoff);
1221err1:		if (mbfd >= 0)
1222			(void) close(mbfd);
1223err0:		unlockmbox();
1224		return;
1225	}
1226
1227	/* Close and check -- NFS doesn't write until the close. */
1228	if (close(mbfd))
1229	{
1230		errcode = "450 4.2.0";
1231#ifdef EDQUOT
1232		if (errno == EDQUOT && BounceQuota)
1233			errcode = "552 5.2.2";
1234#endif /* EDQUOT */
1235		mailerr(errcode, "%s: %s", path, sm_errstring(errno));
1236		(void) truncate(path, curoff);
1237	}
1238	else if (!nobiff)
1239		notifybiff(biffmsg);
1240
1241	if (setreuid(0, 0) < 0)
1242	{
1243		mailerr("450 4.2.0", "setreuid(0, 0): %s",
1244			sm_errstring(errno));
1245		goto err0;
1246	}
1247#ifdef DEBUG
1248	fprintf(stderr, "reset euid = %d\n", (int) geteuid());
1249#endif /* DEBUG */
1250	unlockmbox();
1251	if (LMTPMode)
1252		printf("250 2.1.5 %s Ok\r\n", name);
1253}
1254
1255/*
1256**  user.lock files are necessary for compatibility with other
1257**  systems, e.g., when the mail spool file is NFS exported.
1258**  Alas, mailbox locking is more than just a local matter.
1259**  EPA 11/94.
1260*/
1261
1262bool	Locked = false;
1263
1264#ifdef MAILLOCK
1265int
1266lockmbox(name)
1267	char *name;
1268{
1269	int r = 0;
1270
1271	if (Locked)
1272		return 0;
1273	if ((r = maillock(name, 15)) == L_SUCCESS)
1274	{
1275		Locked = true;
1276		return 0;
1277	}
1278	switch (r)
1279	{
1280	  case L_TMPLOCK:	/* Can't create tmp file */
1281	  case L_TMPWRITE:	/* Can't write pid into lockfile */
1282	  case L_MAXTRYS:	/* Failed after retrycnt attempts */
1283		errno = 0;
1284		r = EX_TEMPFAIL;
1285		break;
1286	  case L_ERROR:		/* Check errno for reason */
1287		r = errno;
1288		break;
1289	  default:		/* other permanent errors */
1290		errno = 0;
1291		r = EX_UNAVAILABLE;
1292		break;
1293	}
1294	return r;
1295}
1296
1297void
1298unlockmbox()
1299{
1300	if (Locked)
1301		mailunlock();
1302	Locked = false;
1303}
1304#else /* MAILLOCK */
1305
1306char	LockName[MAXPATHLEN];
1307
1308int
1309lockmbox(path)
1310	char *path;
1311{
1312	int statfailed = 0;
1313	time_t start;
1314
1315	if (Locked)
1316		return 0;
1317	if (strlen(path) + 6 > sizeof LockName)
1318		return EX_SOFTWARE;
1319	(void) sm_snprintf(LockName, sizeof LockName, "%s.lock", path);
1320	(void) time(&start);
1321	for (; ; sleep(5))
1322	{
1323		int fd;
1324		struct stat st;
1325		time_t now;
1326
1327		/* global timeout */
1328		(void) time(&now);
1329		if (now > start + LOCKTO_GLOB)
1330		{
1331			errno = 0;
1332			return EX_TEMPFAIL;
1333		}
1334		fd = open(LockName, O_WRONLY|O_EXCL|O_CREAT, 0);
1335		if (fd >= 0)
1336		{
1337			/* defeat lock checking programs which test pid */
1338			(void) write(fd, "0", 2);
1339			Locked = true;
1340			(void) close(fd);
1341			return 0;
1342		}
1343		if (stat(LockName, &st) < 0)
1344		{
1345			if (statfailed++ > 5)
1346			{
1347				errno = 0;
1348				return EX_TEMPFAIL;
1349			}
1350			continue;
1351		}
1352		statfailed = 0;
1353		(void) time(&now);
1354		if (now < st.st_ctime + LOCKTO_RM)
1355			continue;
1356
1357		/* try to remove stale lockfile */
1358		if (unlink(LockName) < 0)
1359			return errno;
1360	}
1361}
1362
1363void
1364unlockmbox()
1365{
1366	if (!Locked)
1367		return;
1368	(void) unlink(LockName);
1369	Locked = false;
1370}
1371#endif /* MAILLOCK */
1372
1373void
1374notifybiff(msg)
1375	char *msg;
1376{
1377	static bool initialized = false;
1378	static int f = -1;
1379	struct hostent *hp;
1380	struct servent *sp;
1381	int len;
1382	static struct sockaddr_in addr;
1383
1384	if (!initialized)
1385	{
1386		initialized = true;
1387
1388		/* Be silent if biff service not available. */
1389		if ((sp = getservbyname("biff", "udp")) == NULL ||
1390		    (hp = gethostbyname("localhost")) == NULL ||
1391		    hp->h_length != INADDRSZ)
1392			return;
1393
1394		addr.sin_family = hp->h_addrtype;
1395		memcpy(&addr.sin_addr, hp->h_addr, INADDRSZ);
1396		addr.sin_port = sp->s_port;
1397	}
1398
1399	/* No message, just return */
1400	if (msg == NULL)
1401		return;
1402
1403	/* Couldn't initialize addr struct */
1404	if (addr.sin_family == AF_UNSPEC)
1405		return;
1406
1407	if (f < 0 && (f = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1408		return;
1409	len = strlen(msg) + 1;
1410	(void) sendto(f, msg, len, 0, (struct sockaddr *) &addr, sizeof(addr));
1411}
1412
1413void
1414usage()
1415{
1416	ExitVal = EX_USAGE;
1417	mailerr(NULL, "usage: mail.local [-7] [-B] [-b] [-d] [-l] [-s] [-f from|-r from] [-h filename] user ...");
1418	exit(ExitVal);
1419}
1420
1421void
1422/*VARARGS2*/
1423#ifdef __STDC__
1424mailerr(const char *hdr, const char *fmt, ...)
1425#else /* __STDC__ */
1426mailerr(hdr, fmt, va_alist)
1427	const char *hdr;
1428	const char *fmt;
1429	va_dcl
1430#endif /* __STDC__ */
1431{
1432	size_t len = 0;
1433	SM_VA_LOCAL_DECL
1434
1435	(void) e_to_sys(errno);
1436
1437	SM_VA_START(ap, fmt);
1438
1439	if (LMTPMode && hdr != NULL)
1440	{
1441		sm_snprintf(ErrBuf, sizeof ErrBuf, "%s ", hdr);
1442		len = strlen(ErrBuf);
1443	}
1444	(void) sm_vsnprintf(&ErrBuf[len], sizeof ErrBuf - len, fmt, ap);
1445	SM_VA_END(ap);
1446
1447	if (!HoldErrs)
1448		flush_error();
1449
1450	/* Log the message to syslog. */
1451	if (!LMTPMode)
1452		syslog(LOG_ERR, "%s", ErrBuf);
1453}
1454
1455void
1456flush_error()
1457{
1458	if (LMTPMode)
1459		printf("%s\r\n", ErrBuf);
1460	else
1461	{
1462		if (ExitVal != EX_USAGE)
1463			(void) fprintf(stderr, "mail.local: ");
1464		fprintf(stderr, "%s\n", ErrBuf);
1465	}
1466}
1467
1468/*
1469 * e_to_sys --
1470 *	Guess which errno's are temporary.  Gag me.
1471 */
1472
1473int
1474e_to_sys(num)
1475	int num;
1476{
1477	/* Temporary failures override hard errors. */
1478	if (ExitVal == EX_TEMPFAIL)
1479		return ExitVal;
1480
1481	switch (num)		/* Hopefully temporary errors. */
1482	{
1483#ifdef EDQUOT
1484	  case EDQUOT:		/* Disc quota exceeded */
1485		if (BounceQuota)
1486		{
1487			ExitVal = EX_UNAVAILABLE;
1488			break;
1489		}
1490		/* FALLTHROUGH */
1491#endif /* EDQUOT */
1492#ifdef EAGAIN
1493	  case EAGAIN:		/* Resource temporarily unavailable */
1494#endif /* EAGAIN */
1495#ifdef EBUSY
1496	  case EBUSY:		/* Device busy */
1497#endif /* EBUSY */
1498#ifdef EPROCLIM
1499	  case EPROCLIM:	/* Too many processes */
1500#endif /* EPROCLIM */
1501#ifdef EUSERS
1502	  case EUSERS:		/* Too many users */
1503#endif /* EUSERS */
1504#ifdef ECONNABORTED
1505	  case ECONNABORTED:	/* Software caused connection abort */
1506#endif /* ECONNABORTED */
1507#ifdef ECONNREFUSED
1508	  case ECONNREFUSED:	/* Connection refused */
1509#endif /* ECONNREFUSED */
1510#ifdef ECONNRESET
1511	  case ECONNRESET:	/* Connection reset by peer */
1512#endif /* ECONNRESET */
1513#ifdef EDEADLK
1514	  case EDEADLK:		/* Resource deadlock avoided */
1515#endif /* EDEADLK */
1516#ifdef EFBIG
1517	  case EFBIG:		/* File too large */
1518#endif /* EFBIG */
1519#ifdef EHOSTDOWN
1520	  case EHOSTDOWN:	/* Host is down */
1521#endif /* EHOSTDOWN */
1522#ifdef EHOSTUNREACH
1523	  case EHOSTUNREACH:	/* No route to host */
1524#endif /* EHOSTUNREACH */
1525#ifdef EMFILE
1526	  case EMFILE:		/* Too many open files */
1527#endif /* EMFILE */
1528#ifdef ENETDOWN
1529	  case ENETDOWN:	/* Network is down */
1530#endif /* ENETDOWN */
1531#ifdef ENETRESET
1532	  case ENETRESET:	/* Network dropped connection on reset */
1533#endif /* ENETRESET */
1534#ifdef ENETUNREACH
1535	  case ENETUNREACH:	/* Network is unreachable */
1536#endif /* ENETUNREACH */
1537#ifdef ENFILE
1538	  case ENFILE:		/* Too many open files in system */
1539#endif /* ENFILE */
1540#ifdef ENOBUFS
1541	  case ENOBUFS:		/* No buffer space available */
1542#endif /* ENOBUFS */
1543#ifdef ENOMEM
1544	  case ENOMEM:		/* Cannot allocate memory */
1545#endif /* ENOMEM */
1546#ifdef ENOSPC
1547	  case ENOSPC:		/* No space left on device */
1548#endif /* ENOSPC */
1549#ifdef EROFS
1550	  case EROFS:		/* Read-only file system */
1551#endif /* EROFS */
1552#ifdef ESTALE
1553	  case ESTALE:		/* Stale NFS file handle */
1554#endif /* ESTALE */
1555#ifdef ETIMEDOUT
1556	  case ETIMEDOUT:	/* Connection timed out */
1557#endif /* ETIMEDOUT */
1558#if defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN && EWOULDBLOCK != EDEADLK
1559	  case EWOULDBLOCK:	/* Operation would block. */
1560#endif /* defined(EWOULDBLOCK) && EWOULDBLOCK != EAGAIN && EWOULDBLOCK != EDEADLK */
1561		ExitVal = EX_TEMPFAIL;
1562		break;
1563
1564	  default:
1565		ExitVal = EX_UNAVAILABLE;
1566		break;
1567	}
1568	return ExitVal;
1569}
1570
1571#if defined(ultrix) || defined(_CRAY)
1572/*
1573 * Copyright (c) 1987, 1993
1574 *	The Regents of the University of California.  All rights reserved.
1575 *
1576 * Redistribution and use in source and binary forms, with or without
1577 * modification, are permitted provided that the following conditions
1578 * are met:
1579 * 1. Redistributions of source code must retain the above copyright
1580 *    notice, this list of conditions and the following disclaimer.
1581 * 2. Redistributions in binary form must reproduce the above copyright
1582 *    notice, this list of conditions and the following disclaimer in the
1583 *    documentation and/or other materials provided with the distribution.
1584 * 3. All advertising materials mentioning features or use of this software
1585 *    must display the following acknowledgement:
1586 *	This product includes software developed by the University of
1587 *	California, Berkeley and its contributors.
1588 * 4. Neither the name of the University nor the names of its contributors
1589 *    may be used to endorse or promote products derived from this software
1590 *    without specific prior written permission.
1591 *
1592 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
1593 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1594 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1595 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
1596 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1597 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1598 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1599 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1600 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1601 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1602 * SUCH DAMAGE.
1603 */
1604
1605# if defined(LIBC_SCCS) && !defined(lint)
1606static char sccsid[] = "@(#)mktemp.c	8.1 (Berkeley) 6/4/93";
1607# endif /* defined(LIBC_SCCS) && !defined(lint) */
1608
1609# include <sys/types.h>
1610# include <sys/stat.h>
1611# include <fcntl.h>
1612# include <errno.h>
1613# include <stdio.h>
1614# include <ctype.h>
1615
1616static int _gettemp();
1617
1618mkstemp(path)
1619	char *path;
1620{
1621	int fd;
1622
1623	return (_gettemp(path, &fd) ? fd : -1);
1624}
1625
1626static
1627_gettemp(path, doopen)
1628	char *path;
1629	register int *doopen;
1630{
1631	extern int errno;
1632	register char *start, *trv;
1633	struct stat sbuf;
1634	unsigned int pid;
1635
1636	pid = getpid();
1637	for (trv = path; *trv; ++trv);		/* extra X's get set to 0's */
1638	while (*--trv == 'X')
1639	{
1640		*trv = (pid % 10) + '0';
1641		pid /= 10;
1642	}
1643
1644	/*
1645	 * check the target directory; if you have six X's and it
1646	 * doesn't exist this runs for a *very* long time.
1647	 */
1648	for (start = trv + 1;; --trv)
1649	{
1650		if (trv <= path)
1651			break;
1652		if (*trv == '/')
1653		{
1654			*trv = '\0';
1655			if (stat(path, &sbuf) < 0)
1656				return(0);
1657			if (!S_ISDIR(sbuf.st_mode))
1658			{
1659				errno = ENOTDIR;
1660				return(0);
1661			}
1662			*trv = '/';
1663			break;
1664		}
1665	}
1666
1667	for (;;)
1668	{
1669		if (doopen)
1670		{
1671			if ((*doopen = open(path, O_CREAT|O_EXCL|O_RDWR,
1672					    0600)) >= 0)
1673				return(1);
1674			if (errno != EEXIST)
1675				return(0);
1676		}
1677		else if (stat(path, &sbuf) < 0)
1678			return(errno == ENOENT ? 1 : 0);
1679
1680		/* tricky little algorithm for backward compatibility */
1681		for (trv = start;;)
1682		{
1683			if (!*trv)
1684				return(0);
1685			if (*trv == 'z')
1686				*trv++ = 'a';
1687			else
1688			{
1689				if (isascii(*trv) && isdigit(*trv))
1690					*trv = 'a';
1691				else
1692					++*trv;
1693				break;
1694			}
1695		}
1696	}
1697	/* NOTREACHED */
1698}
1699#endif /* defined(ultrix) || defined(_CRAY) */
1700