1 /* movemail foo bar -- move file foo to file bar,
2 locking file foo the way /bin/mail respects.
3 Copyright (C) 1986, 1992, 1993, 1994, 1996, 1999, 2001, 2002, 2003, 2004,
4 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
6 This file is part of GNU Emacs.
8 GNU Emacs is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
13 GNU Emacs is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
22 /* Important notice: defining MAIL_USE_FLOCK or MAIL_USE_LOCKF *will
23 cause loss of mail* if you do it on a system that does not normally
24 use flock as its way of interlocking access to inbox files. The
25 setting of MAIL_USE_FLOCK and MAIL_USE_LOCKF *must agree* with the
26 system's own conventions. It is not a choice that is up to you.
28 So, if your system uses lock files rather than flock, then the only way
29 you can get proper operation is to enable movemail to write lockfiles there.
30 This means you must either give that directory access modes
31 that permit everyone to write lockfiles in it, or you must make movemail
32 a setuid or setgid program. */
35 * Modified January, 1986 by Michael R. Gretzinger (Project Athena)
37 * Added POP (Post Office Protocol) service. When compiled -DMAIL_USE_POP
38 * movemail will accept input filename arguments of the form
39 * "po:username". This will cause movemail to open a connection to
40 * a pop server running on $MAILHOST (environment variable). Movemail
41 * must be setuid to root in order to work with POP.
43 * New module: popmail.c
45 * main - added code within #ifdef MAIL_USE_POP; added setuid (getuid ())
47 * New routines in movemail.c:
48 * get_errmsg - return pointer to system error message
50 * Modified August, 1993 by Jonathan Kamens (OpenVision Technologies)
52 * Move all of the POP code into a separate file, "pop.c".
53 * Use strerror instead of get_errmsg.
58 #include <sys/types.h>
82 #define DIRECTORY_SEP '/'
84 #ifndef IS_DIRECTORY_SEP
85 #define IS_DIRECTORY_SEP(_c_) ((_c_) == DIRECTORY_SEP)
93 #define wait(var) (*(var) = 0)
94 /* Unfortunately, Samba doesn't seem to properly lock Unix files even
95 though the locking call succeeds (and indeed blocks local access from
96 other NT programs). If you have direct file access using an NFS
97 client or something other than Samba, the locking call might work
98 properly - make sure it does before you enable this!
100 [18-Feb-97 andrewi] I now believe my comment above to be incorrect,
101 since it was based on a misunderstanding of how locking calls are
102 implemented and used on Unix. */
103 //#define DISABLE_DIRECT_ACCESS
106 #endif /* WINDOWSNT */
116 #include <sys/locking.h>
119 #ifdef MAIL_USE_LOCKF
120 #define MAIL_USE_SYSTEM_LOCK
123 #ifdef MAIL_USE_FLOCK
124 #define MAIL_USE_SYSTEM_LOCK
128 extern int lk_open (), lk_close ();
131 #if !defined (MAIL_USE_SYSTEM_LOCK) && !defined (MAIL_USE_MMDF) && \
132 (defined (HAVE_LIBMAIL) || defined (HAVE_LIBLOCKFILE)) && \
133 defined (HAVE_MAILLOCK_H)
134 #include <maillock.h>
135 /* We can't use maillock unless we know what directory system mail
138 #define MAIL_USE_MAILLOCK
139 static char *mail_spool_name ();
145 extern char *index
__P ((const char *, int));
148 extern char *rindex
__P((const char *, int));
153 void pfatal_with_name ();
154 void pfatal_and_delete ();
160 int mbx_delimit_begin ();
161 int mbx_delimit_end ();
163 /* Nonzero means this is name of a lock file to delete on fatal error. */
164 char *delete_lockname
;
171 char *inname
, *outname
;
175 int c
, preserve_mail
= 0;
177 #ifndef MAIL_USE_SYSTEM_LOCK
184 #endif /* not MAIL_USE_SYSTEM_LOCK */
186 #ifdef MAIL_USE_MAILLOCK
191 int pop_reverse_order
= 0;
193 #else /* ! MAIL_USE_POP */
195 #endif /* MAIL_USE_POP */
197 uid_t real_gid
= getgid();
198 uid_t priv_gid
= getegid();
201 /* Ensure all file i/o is in binary mode. */
207 while ((c
= getopt (argc
, argv
, ARGSTR
)) != EOF
)
212 pop_reverse_order
= 1;
225 (argc
- optind
< 2) || (argc
- optind
> 3)
232 fprintf (stderr
, "Usage: movemail [-p] [-r] inbox destfile%s\n",
235 fprintf (stderr
, "Usage: movemail [-p] inbox destfile%s\n", "");
240 inname
= argv
[optind
];
241 outname
= argv
[optind
+1];
248 fatal ("Destination file name is empty", 0, 0);
251 if (!strncmp (inname
, "po:", 3))
255 status
= popmail (inname
+ 3, outname
, preserve_mail
,
256 (argc
- optind
== 3) ? argv
[optind
+2] : NULL
,
261 if (setuid (getuid ()) < 0)
262 fatal ("Failed to drop privileges", 0, 0);
264 #endif /* MAIL_USE_POP */
266 #ifndef DISABLE_DIRECT_ACCESS
267 #ifndef MAIL_USE_MMDF
268 #ifndef MAIL_USE_SYSTEM_LOCK
269 #ifdef MAIL_USE_MAILLOCK
270 spool_name
= mail_spool_name (inname
);
274 /* Use a lock file named after our first argument with .lock appended:
275 If it exists, the mail file is locked. */
276 /* Note: this locking mechanism is *required* by the mailer
277 (on systems which use it) to prevent loss of mail.
279 On systems that use a lock file, extracting the mail without locking
280 WILL occasionally cause loss of mail due to timing errors!
282 So, if creation of the lock file fails
283 due to access permission on the mail spool directory,
284 you simply MUST change the permission
285 and/or make movemail a setgid program
286 so it can create lock files properly.
288 You might also wish to verify that your system is one
289 which uses lock files for this purpose. Some systems use other methods.
291 If your system uses the `flock' system call for mail locking,
292 define MAIL_USE_SYSTEM_LOCK in config.h or the s-*.h file
293 and recompile movemail. If the s- file for your system
294 should define MAIL_USE_SYSTEM_LOCK but does not, send a bug report
295 to bug-gnu-emacs@prep.ai.mit.edu so we can fix it. */
297 lockname
= concat (inname
, ".lock", "");
298 tempname
= (char *) xmalloc (strlen (inname
) + strlen ("EXXXXXX") + 1);
299 strcpy (tempname
, inname
);
300 p
= tempname
+ strlen (tempname
);
301 while (p
!= tempname
&& !IS_DIRECTORY_SEP (p
[-1]))
304 strcpy (p
, "EXXXXXX");
310 /* Create the lock file, but not under the lock file name. */
311 /* Give up if cannot do that. */
312 desc
= open (tempname
, O_WRONLY
| O_CREAT
| O_EXCL
, 0666);
315 char *message
= (char *) xmalloc (strlen (tempname
) + 50);
316 sprintf (message
, "creating %s, which would become the lock file",
318 pfatal_with_name (message
);
322 tem
= link (tempname
, lockname
);
325 if (tem
< 0 && errno
== EPERM
)
326 fatal ("Unable to create hard link between %s and %s",
335 /* If lock file is five minutes old, unlock it.
336 Five minutes should be good enough to cope with crashes
337 and wedgitude, and long enough to avoid being fooled
338 by time differences between machines. */
339 if (stat (lockname
, &st
) >= 0)
342 if (st
.st_ctime
< now
- 300)
347 delete_lockname
= lockname
;
349 #endif /* not MAIL_USE_SYSTEM_LOCK */
350 #endif /* not MAIL_USE_MMDF */
356 #if defined (MAIL_USE_MAILLOCK) && defined (HAVE_TOUCHLOCK)
357 time_t touched_lock
, now
;
360 if (setuid (getuid ()) < 0 || setegid (real_gid
) < 0)
361 fatal ("Failed to drop privileges", 0, 0);
363 #ifndef MAIL_USE_MMDF
364 #ifdef MAIL_USE_SYSTEM_LOCK
365 indesc
= open (inname
, O_RDWR
);
366 #else /* if not MAIL_USE_SYSTEM_LOCK */
367 indesc
= open (inname
, O_RDONLY
);
368 #endif /* not MAIL_USE_SYSTEM_LOCK */
369 #else /* MAIL_USE_MMDF */
370 indesc
= lk_open (inname
, O_RDONLY
, 0, 0, 10);
371 #endif /* MAIL_USE_MMDF */
374 pfatal_with_name (inname
);
377 /* In case movemail is setuid to root, make sure the user can
378 read the output file. */
379 /* This is desirable for all systems
380 but I don't want to assume all have the umask system call */
381 umask (umask (0) & 0333);
382 #endif /* BSD_SYSTEM */
383 outdesc
= open (outname
, O_WRONLY
| O_CREAT
| O_EXCL
, 0666);
385 pfatal_with_name (outname
);
387 if (setegid (priv_gid
) < 0)
388 fatal ("Failed to regain privileges", 0, 0);
390 /* This label exists so we can retry locking
391 after a delay, if it got EAGAIN or EBUSY. */
394 /* Try to lock it. */
395 #ifdef MAIL_USE_MAILLOCK
398 /* The "0 - " is to make it a negative number if maillock returns
400 status
= 0 - maillock (spool_name
, 1);
401 #ifdef HAVE_TOUCHLOCK
402 touched_lock
= time (0);
407 #endif /* MAIL_USE_MAILLOCK */
409 #ifdef MAIL_USE_SYSTEM_LOCK
410 #ifdef MAIL_USE_LOCKF
411 status
= lockf (indesc
, F_LOCK
, 0);
412 #else /* not MAIL_USE_LOCKF */
414 status
= locking (indesc
, LK_RLCK
, -1L);
416 status
= flock (indesc
, LOCK_EX
);
418 #endif /* not MAIL_USE_LOCKF */
419 #endif /* MAIL_USE_SYSTEM_LOCK */
422 /* If it fails, retry up to 5 times
423 for certain failure codes. */
426 if (++lockcount
<= 5)
444 pfatal_with_name (inname
);
452 nread
= read (indesc
, buf
, sizeof buf
);
454 pfatal_with_name (inname
);
455 if (nread
!= write (outdesc
, buf
, nread
))
457 int saved_errno
= errno
;
460 pfatal_with_name (outname
);
462 if (nread
< sizeof buf
)
464 #if defined (MAIL_USE_MAILLOCK) && defined (HAVE_TOUCHLOCK)
468 if (now
- touched_lock
> 60)
474 #endif /* MAIL_USE_MAILLOCK */
479 if (fsync (outdesc
) < 0)
480 pfatal_and_delete (outname
);
483 /* Prevent symlink attacks truncating other users' mailboxes */
484 if (setegid (real_gid
) < 0)
485 fatal ("Failed to drop privileges", 0, 0);
487 /* Check to make sure no errors before we zap the inbox. */
488 if (close (outdesc
) != 0)
489 pfatal_and_delete (outname
);
491 #ifdef MAIL_USE_SYSTEM_LOCK
494 ftruncate (indesc
, 0L);
496 #endif /* MAIL_USE_SYSTEM_LOCK */
499 lk_close (indesc
, 0, 0, 0);
504 #ifndef MAIL_USE_SYSTEM_LOCK
507 /* Delete the input file; if we can't, at least get rid of its
509 #ifdef MAIL_UNLINK_SPOOL
510 /* This is generally bad to do, because it destroys the permissions
511 that were set on the file. Better to just empty the file. */
512 if (unlink (inname
) < 0 && errno
!= ENOENT
)
513 #endif /* MAIL_UNLINK_SPOOL */
514 creat (inname
, 0600);
516 #endif /* not MAIL_USE_SYSTEM_LOCK */
518 /* End of mailbox truncation */
519 if (setegid (priv_gid
) < 0)
520 fatal ("Failed to regain privileges", 0, 0);
522 #ifdef MAIL_USE_MAILLOCK
523 /* This has to occur in the child, i.e., in the process that
524 acquired the lock! */
532 if (!WIFEXITED (status
))
534 else if (WRETCODE (status
) != 0)
535 exit (WRETCODE (status
));
537 #if !defined (MAIL_USE_MMDF) && !defined (MAIL_USE_SYSTEM_LOCK)
538 #ifdef MAIL_USE_MAILLOCK
540 #endif /* MAIL_USE_MAILLOCK */
542 #endif /* not MAIL_USE_MMDF and not MAIL_USE_SYSTEM_LOCK */
544 #endif /* ! DISABLE_DIRECT_ACCESS */
549 #ifdef MAIL_USE_MAILLOCK
550 /* This function uses stat to confirm that the mail directory is
551 identical to the directory of the input file, rather than just
552 string-comparing the two paths, because one or both of them might
553 be symbolic links pointing to some other directory. */
555 mail_spool_name (inname
)
558 struct stat stat1
, stat2
;
562 if (! (fname
= rindex (inname
, '/')))
567 if (stat (MAILDIR
, &stat1
) < 0)
570 indir
= (char *) xmalloc (fname
- inname
+ 1);
571 strncpy (indir
, inname
, fname
- inname
);
572 indir
[fname
-inname
] = '\0';
575 status
= stat (indir
, &stat2
);
582 if (stat1
.st_dev
== stat2
.st_dev
583 && stat1
.st_ino
== stat2
.st_ino
)
588 #endif /* MAIL_USE_MAILLOCK */
590 /* Print error message and exit. */
597 unlink (delete_lockname
);
602 /* Print error message. `s1' is printf control string, `s2' and `s3'
603 are args for it or null. */
609 fprintf (stderr
, "movemail: ");
611 fprintf (stderr
, s1
, s2
, s3
);
613 fprintf (stderr
, s1
, s2
);
615 fprintf (stderr
, s1
);
616 fprintf (stderr
, "\n");
620 pfatal_with_name (name
)
623 fatal ("%s for %s", strerror (errno
), name
);
627 pfatal_and_delete (name
)
630 char *s
= strerror (errno
);
632 fatal ("%s for %s", s
, name
);
635 /* Return a newly-allocated string whose contents concatenate those of s1, s2, s3. */
641 int len1
= strlen (s1
), len2
= strlen (s2
), len3
= strlen (s3
);
642 char *result
= (char *) xmalloc (len1
+ len2
+ len3
+ 1);
645 strcpy (result
+ len1
, s2
);
646 strcpy (result
+ len1
+ len2
, s3
);
647 *(result
+ len1
+ len2
+ len3
) = 0;
652 /* Like malloc but get fatal error if memory is exhausted. */
658 long *result
= (long *) malloc (size
);
660 fatal ("virtual memory exhausted", 0, 0);
664 /* This is the guts of the interface to the Post Office Protocol. */
669 #include <sys/socket.h>
670 #include <netinet/in.h>
686 char ibuffer
[BUFSIZ
];
687 char obuffer
[BUFSIZ
];
688 char Errmsg
[200]; /* POP errors, at least, can exceed
689 the original length of 80. */
692 * The full valid syntax for a POP mailbox specification for movemail
693 * is "po:username:hostname". The ":hostname" is optional; if it is
694 * omitted, the MAILHOST environment variable will be consulted. Note
695 * that by the time popmail() is called the "po:" has been stripped
696 * off of the front of the mailbox name.
698 * If the mailbox is in the form "po:username:hostname", then it is
699 * modified by this function -- the second colon is replaced by a
702 * Return a value suitable for passing to `exit'.
706 popmail (mailbox
, outfile
, preserve
, password
, reverse_order
)
719 int start
, end
, increment
;
720 char *user
, *hostname
;
723 if ((hostname
= index(mailbox
, ':')))
726 server
= pop_open (hostname
, user
, password
, POP_NO_GETPASS
);
729 error ("Error connecting to POP server: %s", pop_error
, 0);
733 if (pop_stat (server
, &nmsgs
, &nbytes
))
735 error ("Error getting message count from POP server: %s", pop_error
, 0);
745 mbfi
= open (outfile
, O_WRONLY
| O_CREAT
| O_EXCL
, 0666);
749 error ("Error in open: %s, %s", strerror (errno
), outfile
);
752 fchown (mbfi
, getuid (), -1);
754 if ((mbf
= fdopen (mbfi
, "wb")) == NULL
)
757 error ("Error in fdopen: %s", strerror (errno
), 0);
776 for (i
= start
; i
* increment
<= end
* increment
; i
+= increment
)
778 mbx_delimit_begin (mbf
);
779 if (pop_retr (server
, i
, mbf
) != OK
)
781 error ("%s", Errmsg
, 0);
785 mbx_delimit_end (mbf
);
789 error ("Error in fflush: %s", strerror (errno
), 0);
796 /* On AFS, a call to write only modifies the file in the local
797 * workstation's AFS cache. The changes are not written to the server
798 * until a call to fsync or close is made. Users with AFS home
799 * directories have lost mail when over quota because these checks were
800 * not made in previous versions of movemail. */
803 if (fsync (mbfi
) < 0)
805 error ("Error in fsync: %s", strerror (errno
), 0);
810 if (close (mbfi
) == -1)
812 error ("Error in close: %s", strerror (errno
), 0);
817 for (i
= 1; i
<= nmsgs
; i
++)
819 if (pop_delete (server
, i
))
821 error ("Error from POP server: %s", pop_error
, 0);
827 if (pop_quit (server
))
829 error ("Error from POP server: %s", pop_error
, 0);
837 pop_retr (server
, msgno
, arg
)
842 extern char *strerror ();
846 if (pop_retrieve_first (server
, msgno
, &line
))
848 char *error
= concat ("Error from POP server: ", pop_error
, "");
849 strncpy (Errmsg
, error
, sizeof (Errmsg
));
850 Errmsg
[sizeof (Errmsg
)-1] = '\0';
855 while ((ret
= pop_retrieve_next (server
, &line
)) >= 0)
860 if (mbx_write (line
, ret
, arg
) != OK
)
862 strcpy (Errmsg
, strerror (errno
));
870 char *error
= concat ("Error from POP server: ", pop_error
, "");
871 strncpy (Errmsg
, error
, sizeof (Errmsg
));
872 Errmsg
[sizeof (Errmsg
)-1] = '\0';
880 /* Do this as a macro instead of using strcmp to save on execution time. */
881 #define IS_FROM_LINE(a) ((a[0] == 'F') \
888 mbx_write (line
, len
, mbf
)
893 #ifdef MOVEMAIL_QUOTE_POP_FROM_LINES
894 if (IS_FROM_LINE (line
))
896 if (fputc ('>', mbf
) == EOF
)
900 if (line
[0] == '\037')
902 if (fputs ("^_", mbf
) == EOF
)
907 if (fwrite (line
, 1, len
, mbf
) != len
)
909 if (fputc (0x0a, mbf
) == EOF
)
915 mbx_delimit_begin (mbf
)
920 char fromline
[40] = "From movemail ";
923 ltime
= localtime (&now
);
925 strcat (fromline
, asctime (ltime
));
927 if (fputs (fromline
, mbf
) == EOF
)
933 mbx_delimit_end (mbf
)
936 if (putc ('\n', mbf
) == EOF
)
941 #endif /* MAIL_USE_POP */
943 #ifndef HAVE_STRERROR
948 extern char *sys_errlist
[];
951 if (errnum
>= 0 && errnum
< sys_nerr
)
952 return sys_errlist
[errnum
];
953 return (char *) "Unknown error";
956 #endif /* ! HAVE_STRERROR */
958 /* arch-tag: 1c323112-41fe-4fe5-8de9-494de631f73f
959 (do not change this comment) */
961 /* movemail.c ends here */