1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2020 */
6 /* Copyright (c) The Exim maintainers 2020 - 2021 */
7 /* See the file NOTICE for conditions of use and distribution. */
11 #include "appendfile.h"
13 #ifdef SUPPORT_MAILDIR
14 #include "tf_maildir.h"
18 /* Options specific to the appendfile transport. They must be in alphabetic
19 order (note that "_" comes before the lower case letters). Some of them are
20 stored in the publicly visible instance block - these are flagged with the
22 #define LOFF(field) OPT_OFF(appendfile_transport_options_block, field)
24 optionlist appendfile_transport_options[] = {
25 #ifdef SUPPORT_MAILDIR
26 { "*expand_maildir_use_size_file", opt_stringptr, LOFF(expand_maildir_use_size_file) },
28 { "*set_use_fcntl_lock",opt_bool | opt_hidden, LOFF(set_use_fcntl) },
29 { "*set_use_flock_lock",opt_bool | opt_hidden, LOFF(set_use_flock) },
30 { "*set_use_lockfile", opt_bool | opt_hidden, LOFF(set_use_lockfile) },
32 { "*set_use_mbx_lock", opt_bool | opt_hidden, LOFF(set_use_mbx_lock) },
34 { "allow_fifo", opt_bool, LOFF(allow_fifo) },
35 { "allow_symlink", opt_bool, LOFF(allow_symlink) },
36 { "batch_id", opt_stringptr | opt_public, OPT_OFF(transport_instance, batch_id) },
37 { "batch_max", opt_int | opt_public, OPT_OFF(transport_instance, batch_max) },
38 { "check_group", opt_bool, LOFF(check_group) },
39 { "check_owner", opt_bool, LOFF(check_owner) },
40 { "check_string", opt_stringptr, LOFF(check_string) },
41 { "create_directory", opt_bool, LOFF(create_directory) },
42 { "create_file", opt_stringptr, LOFF(create_file_string) },
43 { "directory", opt_stringptr, LOFF(dirname) },
44 { "directory_file", opt_stringptr, LOFF(dirfilename) },
45 { "directory_mode", opt_octint, LOFF(dirmode) },
46 { "escape_string", opt_stringptr, LOFF(escape_string) },
47 { "file", opt_stringptr, LOFF(filename) },
48 { "file_format", opt_stringptr, LOFF(file_format) },
49 { "file_must_exist", opt_bool, LOFF(file_must_exist) },
50 { "lock_fcntl_timeout", opt_time, LOFF(lock_fcntl_timeout) },
51 { "lock_flock_timeout", opt_time, LOFF(lock_flock_timeout) },
52 { "lock_interval", opt_time, LOFF(lock_interval) },
53 { "lock_retries", opt_int, LOFF(lock_retries) },
54 { "lockfile_mode", opt_octint, LOFF(lockfile_mode) },
55 { "lockfile_timeout", opt_time, LOFF(lockfile_timeout) },
56 { "mailbox_filecount", opt_stringptr, LOFF(mailbox_filecount_string) },
57 { "mailbox_size", opt_stringptr, LOFF(mailbox_size_string) },
58 #ifdef SUPPORT_MAILDIR
59 { "maildir_format", opt_bool, LOFF(maildir_format ) } ,
60 { "maildir_quota_directory_regex", opt_stringptr, LOFF(maildir_dir_regex) },
61 { "maildir_retries", opt_int, LOFF(maildir_retries) },
62 { "maildir_tag", opt_stringptr, LOFF(maildir_tag) },
63 { "maildir_use_size_file", opt_expand_bool, LOFF(maildir_use_size_file ) } ,
64 { "maildirfolder_create_regex", opt_stringptr, LOFF(maildirfolder_create_regex ) },
65 #endif /* SUPPORT_MAILDIR */
66 #ifdef SUPPORT_MAILSTORE
67 { "mailstore_format", opt_bool, LOFF(mailstore_format ) },
68 { "mailstore_prefix", opt_stringptr, LOFF(mailstore_prefix ) },
69 { "mailstore_suffix", opt_stringptr, LOFF(mailstore_suffix ) },
70 #endif /* SUPPORT_MAILSTORE */
72 { "mbx_format", opt_bool, LOFF(mbx_format ) } ,
73 #endif /* SUPPORT_MBX */
74 { "message_prefix", opt_stringptr, LOFF(message_prefix) },
75 { "message_suffix", opt_stringptr, LOFF(message_suffix) },
76 { "mode", opt_octint, LOFF(mode) },
77 { "mode_fail_narrower",opt_bool, LOFF(mode_fail_narrower) },
78 { "notify_comsat", opt_bool, LOFF(notify_comsat) },
79 { "quota", opt_stringptr, LOFF(quota) },
80 { "quota_directory", opt_stringptr, LOFF(quota_directory) },
81 { "quota_filecount", opt_stringptr, LOFF(quota_filecount) },
82 { "quota_is_inclusive", opt_bool, LOFF(quota_is_inclusive) },
83 { "quota_size_regex", opt_stringptr, LOFF(quota_size_regex) },
84 { "quota_warn_message", opt_stringptr | opt_public, OPT_OFF(transport_instance, warn_message) },
85 { "quota_warn_threshold", opt_stringptr, LOFF(quota_warn_threshold) },
86 { "use_bsmtp", opt_bool, LOFF(use_bsmtp) },
87 { "use_crlf", opt_bool, LOFF(use_crlf) },
88 { "use_fcntl_lock", opt_bool_set, LOFF(use_fcntl) },
89 { "use_flock_lock", opt_bool_set, LOFF(use_flock) },
90 { "use_lockfile", opt_bool_set, LOFF(use_lockfile) },
92 { "use_mbx_lock", opt_bool_set, LOFF(use_mbx_lock) },
93 #endif /* SUPPORT_MBX */
96 /* Size of the options list. An extern variable has to be used so that its
97 address can appear in the tables drtables.c. */
99 int appendfile_transport_options_count =
100 sizeof(appendfile_transport_options)/sizeof(optionlist);
106 appendfile_transport_options_block appendfile_transport_option_defaults = {0};
107 void appendfile_transport_init(transport_instance *tblock) {}
108 BOOL appendfile_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
110 #else /*!MACRO_PREDEF*/
112 /* Default private options block for the appendfile transport. */
114 appendfile_transport_options_block appendfile_transport_option_defaults = {
115 /* all non-mentioned members zero/null/false */
116 .dirfilename = US"q${base62:$tod_epoch}-$inode",
117 .create_file_string = US"anywhere",
118 .maildir_dir_regex = US"^(?:cur|new|\\..*)$",
119 .mailbox_size_value = -1,
120 .mailbox_filecount_value = -1,
121 .mode = APPENDFILE_MODE,
122 .dirmode = APPENDFILE_DIRECTORY_MODE,
123 .lockfile_mode = APPENDFILE_LOCKFILE_MODE,
124 .lockfile_timeout = 30*60,
127 .maildir_retries = 10,
128 .create_file = create_anywhere,
130 .create_directory = TRUE,
131 .notify_comsat = FALSE,
132 .use_lockfile = TRUE,
134 .mode_fail_narrower = TRUE,
135 .quota_is_inclusive = TRUE,
139 /* Encodings for mailbox formats, and their names. MBX format is actually
140 supported only if SUPPORT_MBX is set. */
142 enum { mbf_unix, mbf_mbx, mbf_smail, mbf_maildir, mbf_mailstore };
144 static const char *mailbox_formats[] = {
145 "unix", "mbx", "smail", "maildir", "mailstore" };
148 /* Check warn threshold only if quota size set or not a percentage threshold
149 percentage check should only be done if quota > 0 */
151 #define THRESHOLD_CHECK (ob->quota_warn_threshold_value > 0 && \
152 (!ob->quota_warn_threshold_is_percent || ob->quota_value > 0))
156 /*************************************************
157 * Setup entry point *
158 *************************************************/
160 /* Called for each delivery in the privileged state, just before the uid/gid
161 are changed and the main entry point is called. We use this function to
162 expand any quota settings, so that it can access files that may not be readable
163 by the user. It is also used to pick up external mailbox size information, if
167 tblock points to the transport instance
168 addrlist addresses about to be delivered (not used)
169 dummy not used (doesn't pass back data)
170 uid the uid that will be set (not used)
171 gid the gid that will be set (not used)
172 errmsg where to put an error message
174 Returns: OK, FAIL, or DEFER
178 appendfile_transport_setup(transport_instance *tblock, address_item *addrlist,
179 transport_feedback *dummy, uid_t uid, gid_t gid, uschar **errmsg)
181 appendfile_transport_options_block *ob =
182 (appendfile_transport_options_block *)(tblock->options_block);
183 uschar *q = ob->quota;
184 double default_value = 0.0;
186 if (ob->expand_maildir_use_size_file)
187 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
188 US"`maildir_use_size_file` in transport", tblock->name);
190 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
193 for (int i = 0; i < 5; i++)
195 double d = default_value;
197 uschar *which = NULL;
203 if (!(s = expand_string(q)))
205 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
206 "%s", q, tblock->name, expand_string_message);
207 return f.search_find_defer ? DEFER : FAIL;
210 d = Ustrtod(s, &rest);
212 /* Handle following characters K, M, G, %, the latter being permitted
213 for quota_warn_threshold only. A threshold with no quota setting is
216 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
217 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
218 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
219 else if (*rest == '%' && i == 2)
221 if (ob->quota_value <= 0 && !ob->maildir_use_size_file)
223 else if ((int)d < 0 || (int)d > 100)
225 *errmsg = string_sprintf("Invalid quota_warn_threshold percentage (%d)"
226 " for %s transport", (int)d, tblock->name);
229 ob->quota_warn_threshold_is_percent = TRUE;
234 /* For quota and quota_filecount there may be options
235 appended. Currently only "no_check", so we can be lazy parsing it */
236 if (i < 2 && Ustrstr(rest, "/no_check") == rest)
239 rest += sizeof("/no_check") - 1;
242 Uskip_whitespace(&rest);
246 *errmsg = string_sprintf("Malformed value \"%s\" (expansion of \"%s\") "
247 "in %s transport", s, q, tblock->name);
252 /* Set each value, checking for possible overflow. */
257 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
259 ob->quota_value = (off_t)d;
260 ob->quota_no_check = no_check;
261 q = ob->quota_filecount;
265 if (d >= 2.0*1024.0*1024.0*1024.0)
266 which = US"quota_filecount";
267 ob->quota_filecount_value = (int)d;
268 ob->quota_filecount_no_check = no_check;
269 q = ob->quota_warn_threshold;
273 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
274 which = US"quota_warn_threshold";
275 ob->quota_warn_threshold_value = (off_t)d;
276 q = ob->mailbox_size_string;
277 default_value = -1.0;
281 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
282 which = US"mailbox_size";;
283 ob->mailbox_size_value = (off_t)d;
284 q = ob->mailbox_filecount_string;
288 if (d >= 2.0*1024.0*1024.0*1024.0)
289 which = US"mailbox_filecount";
290 ob->mailbox_filecount_value = (int)d;
296 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
297 "%s transport", which, d, tblock->name);
307 /*************************************************
308 * Initialization entry point *
309 *************************************************/
311 /* Called for each instance, after its options have been read, to
312 enable consistency checks to be done, or anything else that needs
316 appendfile_transport_init(transport_instance *tblock)
318 appendfile_transport_options_block *ob =
319 (appendfile_transport_options_block *)(tblock->options_block);
322 /* Set up the setup entry point, to be called in the privileged state */
324 tblock->setup = appendfile_transport_setup;
326 /* Lock_retries must be greater than zero */
328 if (ob->lock_retries == 0) ob->lock_retries = 1;
330 /* Only one of a file name or directory name must be given. */
332 if (ob->filename && ob->dirname)
333 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
334 "only one of \"file\" or \"directory\" can be specified", tblock->name);
336 /* If a file name was specified, neither quota_filecount nor quota_directory
341 if (ob->quota_filecount)
342 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
343 "quota_filecount must not be set without \"directory\"", tblock->name);
344 if (ob->quota_directory)
345 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
346 "quota_directory must not be set without \"directory\"", tblock->name);
349 /* The default locking depends on whether MBX is set or not. Change the
350 built-in default if none of the lock options has been explicitly set. At least
351 one form of locking is required in all cases, but mbx locking changes the
352 meaning of fcntl and flock locking. */
354 /* Not all operating systems provide flock(). For those that do, if flock is
355 requested, the default for fcntl is FALSE. */
360 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
361 "flock() support was not available in the operating system when this "
362 "binary was built", tblock->name);
363 #endif /* NO_FLOCK */
364 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
369 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
370 !ob->set_use_mbx_lock)
372 ob->use_lockfile = ob->use_flock = FALSE;
373 ob->use_mbx_lock = ob->use_fcntl = TRUE;
375 else if (ob->use_mbx_lock)
377 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
378 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
379 if (!ob->set_use_flock) ob->use_flock = FALSE;
380 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
382 #endif /* SUPPORT_MBX */
384 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
385 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
386 "no locking configured", tblock->name);
388 /* Unset timeouts for non-used locking types */
390 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
391 if (!ob->use_flock) ob->lock_flock_timeout = 0;
393 /* If a directory name was specified, only one of maildir or mailstore may be
394 specified, and if quota_filecount or quota_directory is given, quota must
399 if (ob->maildir_format && ob->mailstore_format)
400 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
401 "only one of maildir and mailstore may be specified", tblock->name);
402 if (ob->quota_filecount != NULL && ob->quota == NULL)
403 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
404 "quota must be set if quota_filecount is set", tblock->name);
405 if (ob->quota_directory != NULL && ob->quota == NULL)
406 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
407 "quota must be set if quota_directory is set", tblock->name);
410 /* If a fixed uid field is set, then a gid field must also be set. */
412 if (tblock->uid_set && !tblock->gid_set && !tblock->expand_gid)
413 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
414 "user set without group for the %s transport", tblock->name);
416 /* If "create_file" is set, check that a valid option is given, and set the
419 if ((s = ob->create_file_string ) && *s)
422 if (Ustrcmp(s, "anywhere") == 0) val = create_anywhere;
423 else if (*s == '/' || Ustrcmp(s, "belowhome") == 0) val = create_belowhome;
424 else if (Ustrcmp(s, "inhome") == 0) val = create_inhome;
426 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
427 "invalid value given for \"create_file\" for the %s transport: '%s'",
429 ob->create_file = val;
432 /* If quota_warn_threshold is set, set up default for warn_message. It may
433 not be used if the actual threshold for a given delivery ends up as zero,
434 of if it's given as a percentage and there's no quota setting. */
436 if (ob->quota_warn_threshold)
438 if (!tblock->warn_message) tblock->warn_message = US
439 "To: $local_part@$domain\n"
440 "Subject: Your mailbox\n\n"
441 "This message is automatically created by mail delivery software (Exim).\n\n"
442 "The size of your mailbox has exceeded a warning threshold that is\n"
443 "set by the system administrator.\n";
446 /* If batch SMTP is set, force the check and escape strings, and arrange that
447 headers are also escaped. */
451 ob->check_string = US".";
452 ob->escape_string = US"..";
453 ob->options |= topt_escape_headers;
456 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
457 insert default values for for the affixes and the check/escape strings. */
459 else if (!ob->dirname && !ob->maildir_format && !ob->mailstore_format)
461 if (!ob->message_prefix) ob->message_prefix =
462 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
463 if (!ob->message_suffix) ob->message_suffix = US"\n";
464 if (!ob->check_string) ob->check_string = US"From ";
465 if (!ob->escape_string) ob->escape_string = US">From ";
469 /* Set up the bitwise options for transport_write_message from the various
470 driver options. Only one of body_only and headers_only can be set. */
473 (tblock->body_only ? topt_no_headers : 0) |
474 (tblock->headers_only ? topt_no_body : 0) |
475 (tblock->return_path_add ? topt_add_return_path : 0) |
476 (tblock->delivery_date_add ? topt_add_delivery_date : 0) |
477 (tblock->envelope_to_add ? topt_add_envelope_to : 0) |
478 ((ob->use_crlf || ob->mbx_format) ? topt_use_crlf : 0);
483 /*************************************************
485 *************************************************/
487 /* The comsat daemon is the thing that provides asynchronous notification of
488 the arrival of local messages, if requested by the user by "biff y". It is a
489 BSD thing that uses a TCP/IP protocol for communication. A message consisting
490 of the text "user@offset" must be sent, where offset is the place in the
491 mailbox where new mail starts. There is no scope for telling it which file to
492 look at, which makes it a less than useful if mail is being delivered into a
493 non-standard place such as the user's home directory. In fact, it doesn't seem
494 to pay much attention to the offset.
498 offset offset in mailbox
504 notify_comsat(uschar *user, off_t offset)
510 DEBUG(D_transport) debug_printf("notify_comsat called\n");
512 s = string_sprintf("%.200s@" OFF_T_FMT "\n", user, offset);
514 if ((sp = getservbyname("biff", "udp")) == NULL)
516 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
520 host.name = US"localhost";
524 /* This code is all set up to look up "localhost" and use all its addresses
525 until one succeeds. However, it appears that at least on some systems, comsat
526 doesn't listen on the ::1 address. So for the moment, just force the address to
527 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
528 can be changed. (But actually, comsat is probably dying out anyway.) */
531 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
533 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
538 host.address = US"127.0.0.1";
541 for (host_item * h = &host; h; h = h->next)
544 int host_af = Ustrchr(h->address, ':') != NULL ? AF_INET6 : AF_INET;
546 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
548 if ((sock = ip_socket(SOCK_DGRAM, host_af)) < 0) continue;
550 /* Connect never fails for a UDP socket, so don't set a timeout. */
552 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0, NULL);
553 rc = send(sock, s, Ustrlen(s) + 1, 0);
558 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
565 /*************************************************
566 * Check the format of a file *
567 *************************************************/
569 /* This function is called when file_format is set, to check that an existing
570 file has the right format. The format string contains text/transport pairs. The
571 string matching is literal. we just read big_buffer_size bytes, because this is
572 all about the first few bytes of a file.
576 tblock the transport block
577 addr the address block - for inserting error data
579 Returns: pointer to the required transport, or NULL
583 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
585 const uschar *format =
586 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
588 int len = read(cfd, data, sizeof(data));
592 DEBUG(D_transport) debug_printf("checking file format\n");
594 /* An empty file matches the current transport */
596 if (len == 0) return tblock;
598 /* Search the formats for a match */
600 /* not expanded so cannot be tainted */
601 while ((s = string_nextinlist(&format, &sep, big_buffer, big_buffer_size)))
603 int slen = Ustrlen(s);
604 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
605 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
609 for (transport_instance * tt = transports; tt; tt = tt->next)
610 if (Ustrcmp(tp, tt->name) == 0)
613 debug_printf("file format -> %s transport\n", tt->name);
616 addr->basic_errno = ERRNO_BADTRANSPORT;
617 addr->message = string_sprintf("%s transport (for %.*s format) not found",
623 /* Failed to find a match */
625 addr->basic_errno = ERRNO_FORMATUNKNOWN;
626 addr->message = US"mailbox file format unrecognized";
633 /*************************************************
634 * Check directory's files for quota *
635 *************************************************/
637 /* This function is called if quota is set for one of the delivery modes that
638 delivers into a specific directory. It scans the directory and stats all the
639 files in order to get a total size and count. This is an expensive thing to do,
640 but some people are prepared to bear the cost. Alternatively, if size_regex is
641 set, it is used as a regex to try to extract the size from the file name, a
642 strategy that some people use on maildir files on systems where the users have
645 The function is global, because it is also called from tf_maildir.c for maildir
646 folders (which should contain only regular files).
648 Note: Any problems can be written to debugging output, but cannot be written to
649 the log, because we are running as an unprivileged user here.
652 dirname the name of the directory
653 countptr where to add the file count (because this function recurses)
654 re a compiled regex to get the size from a name
656 Returns: the sum of the sizes of the stattable files
657 zero if the directory cannot be opened
661 check_dir_size(const uschar * dirname, int * countptr, const pcre2_code * re)
665 int count = *countptr;
667 if (!(dir = exim_opendir(dirname))) return 0;
669 for (struct dirent *ent; ent = readdir(dir); )
671 uschar * path, * name = US ent->d_name;
674 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
678 /* If there's a regex, try to find the size using it */
682 pcre2_match_data * md = pcre2_match_data_create(2, pcre_gen_ctx);
683 int rc = pcre2_match(re, (PCRE2_SPTR)name, PCRE2_ZERO_TERMINATED,
684 0, 0, md, pcre_mtc_ctx);
685 PCRE2_SIZE * ovec = pcre2_get_ovector_pointer(md);
687 && (rc = pcre2_get_ovector_count(md)) >= 2)
690 off_t size = (off_t)Ustrtod(name + ovec[2], &endptr);
691 if (endptr == name + ovec[3])
695 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
701 debug_printf("check_dir_size: regex did not match %s\n", name);
704 /* No regex or no match for the regex, or captured non-digits */
706 path = string_sprintf("%s/%s", dirname, name);
708 if (Ustat(path, &statbuf) < 0)
711 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, path,
715 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
716 sum += statbuf.st_size / statbuf.st_nlink;
717 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
718 sum += check_dir_size(path, &count, re);
723 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
733 /*************************************************
734 * Apply a lock to a file descriptor *
735 *************************************************/
737 /* This function applies a lock to a file descriptor, using a blocking or
738 non-blocking lock, depending on the timeout value. It can apply either or
739 both of a fcntl() and a flock() lock. However, not all OS support flock();
740 for those that don't, the use_flock option cannot be set.
743 fd the file descriptor
744 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
745 fcntl() format); the flock() type is deduced if needed
746 dofcntl do fcntl() locking
747 fcntltime non-zero to use blocking fcntl()
748 doflock do flock() locking
749 flocktime non-zero to use blocking flock()
751 Returns: yield of the fcntl() or flock() call, with errno preserved;
752 sigalrm_seen set if there has been a timeout
756 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
761 struct flock lock_data;
762 lock_data.l_type = fcntltype;
763 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
765 sigalrm_seen = FALSE;
772 yield = fcntl(fd, F_SETLKW, &lock_data);
777 else yield = fcntl(fd, F_SETLK, &lock_data);
781 if (doflock && (yield >= 0))
783 int flocktype = (fcntltype == F_WRLCK) ? LOCK_EX : LOCK_SH;
787 yield = flock(fd, flocktype);
792 else yield = flock(fd, flocktype | LOCK_NB);
794 #endif /* NO_FLOCK */
803 /*************************************************
804 * Copy message into MBX mailbox *
805 *************************************************/
807 /* This function is called when a message intended for a MBX mailbox has been
808 written to a temporary file. We can now get the size of the message and then
809 copy it in MBX format to the mailbox.
812 to_fd fd to write to (the real mailbox)
813 from_fd fd to read from (the temporary file)
814 saved_size current size of mailbox
816 Returns: OK if all went well, DEFER otherwise, with errno preserved
817 the number of bytes written are added to transport_count
818 by virtue of calling transport_write_block()
821 /* Values taken from c-client */
823 #define MBX_HDRSIZE 2048
824 #define MBX_NUSERFLAGS 30
827 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
832 transport_ctx tctx = { .u={.fd = to_fd}, .options = topt_not_socket };
834 /* If the current mailbox size is zero, write a header block */
839 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
840 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
841 (long int)time(NULL));
842 for (int i = 0; i < MBX_NUSERFLAGS; i++)
843 sprintf (CS(s += Ustrlen(s)), "\015\012");
844 if (!transport_write_block (&tctx, deliver_out_buffer, MBX_HDRSIZE, FALSE))
848 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
850 /* Now construct the message's header from the time and the RFC822 file
851 size, including CRLFs, which is the size of the input (temporary) file. */
853 if (fstat(from_fd, &statbuf) < 0) return DEFER;
854 size = statbuf.st_size;
856 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
857 tod_stamp(tod_mbx), size, 0L, 0, 0);
858 used = Ustrlen(deliver_out_buffer);
860 /* Rewind the temporary file, and copy it over in chunks. */
862 if (lseek(from_fd, 0 , SEEK_SET) < 0) return DEFER;
866 int len = read(from_fd, deliver_out_buffer + used,
867 DELIVER_OUT_BUFFER_SIZE - used);
870 if (len == 0) errno = ERRNO_MBXLENGTH;
873 if (!transport_write_block(&tctx, deliver_out_buffer, used + len, FALSE))
881 #endif /* SUPPORT_MBX */
885 /*************************************************
886 * Check creation is permitted *
887 *************************************************/
889 /* This function checks whether a given file name is permitted to be created,
890 as controlled by the create_file option. If no home directory is set, however,
891 we can't do any tests.
894 filename the file name
895 create_file the ob->create_file option
896 deliver_dir the delivery directory
898 Returns: TRUE if creation is permitted
902 check_creation(uschar *filename, int create_file, const uschar * deliver_dir)
906 if (deliver_dir && create_file != create_anywhere)
908 int len = Ustrlen(deliver_dir);
909 uschar *file = filename;
911 while (file[0] == '/' && file[1] == '/') file++;
912 if ( Ustrncmp(file, deliver_dir, len) != 0
914 || Ustrchr(file+len+2, '/') != NULL
915 && ( create_file != create_belowhome
916 || Ustrstr(file+len, "/../") != NULL
920 /* If yield is TRUE, the file name starts with the home directory, and does
921 not contain any instances of "/../" in the "belowhome" case. However, it may
922 still contain symbolic links. We can check for this by making use of
923 realpath(), which most Unixes seem to have (but make it possible to cut this
924 out). We can't just use realpath() on the whole file name, because we know
925 the file itself doesn't exist, and intermediate directories may also not
926 exist. What we want to know is the real path of the longest existing part of
927 the path. That must match the home directory's beginning, whichever is the
931 if (yield && create_file == create_belowhome)
935 for (uschar * slash = Ustrrchr(file, '/'); /* There is known to be one */
936 !rp && slash > file; /* Stop if reached beginning */
940 rp = US realpath(CS file, CS big_buffer);
941 next = Ustrrchr(file, '/');
945 /* If rp == NULL it means that none of the relevant directories exist.
946 This is not a problem here - it means that no symbolic links can exist,
947 which is all we are worried about. Otherwise, we must compare it
948 against the start of the home directory. However, that may itself
949 contain symbolic links, so we have to "realpath" it as well, if
954 uschar hdbuffer[PATH_MAX+1];
955 const uschar * rph = deliver_dir;
956 int rlen = Ustrlen(big_buffer);
958 if ((rp = US realpath(CS deliver_dir, CS hdbuffer)))
964 if (rlen > len) rlen = len;
965 if (Ustrncmp(rph, big_buffer, rlen) != 0)
968 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
969 big_buffer, deliver_dir);
973 #endif /* NO_REALPATH */
981 /*************************************************
983 *************************************************/
985 /* See local README for general interface details. This transport always
986 returns FALSE, indicating that the status which has been placed in the first
987 address should be copied to any other addresses in a batch.
989 Appendfile delivery is tricky and has led to various security problems in other
990 mailers. The logic used here is therefore laid out in some detail. When this
991 function is called, we are running in a subprocess which has had its gid and
992 uid set to the appropriate values. Therefore, we cannot write directly to the
993 exim logs. Any errors must be handled by setting appropriate return codes.
994 Note that the default setting for addr->transport_return is DEFER, so it need
995 not be set unless some other value is required.
997 The code below calls geteuid() rather than getuid() to get the current uid
998 because in weird configurations not running setuid root there may be a
999 difference. In the standard configuration, where setuid() has been used in the
1000 delivery process, there will be no difference between the uid and the euid.
1002 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1003 alias expansion. Otherwise, there must be a configured file name or
1006 The following items apply in the case when a file name (as opposed to a
1007 directory name) is given, that is, when appending to a single file:
1009 (2f) Expand the file name.
1011 (3f) If the file name is /dev/null, return success (optimization).
1013 (4f) If the file_format options is set, open the file for reading, and check
1014 that the bytes at the start of the file match one of the given strings.
1015 If the check indicates a transport other than the current one should be
1016 used, pass control to that other transport. Otherwise continue. An empty
1017 or non-existent file matches the current transport. The file is closed
1020 (5f) If a lock file is required, create it (see extensive separate comments
1021 below about the algorithm for doing this). It is important to do this
1022 before opening the mailbox if NFS is in use.
1024 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1025 details of any symbolic link.
1027 (7f) If the file already exists:
1029 Check the owner and group if necessary, and defer if they are wrong.
1031 If it is a symbolic link AND the allow_symlink option is set (NOT the
1032 default), go back to (6f) but this time use stat() instead of lstat().
1034 If it's not a regular file (or FIFO when permitted), defer delivery.
1036 Check permissions. If the required permissions are *less* than the
1037 existing ones, or supplied by the address (often by the user via filter),
1038 chmod() the file. Otherwise, defer.
1040 Save the inode number.
1042 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1044 If open fails because the file does not exist, go to (6f); on any other
1047 Check the inode number hasn't changed - I realize this isn't perfect (an
1048 inode can be reused) but it's cheap and will catch some of the races.
1050 Check it's still a regular file (or FIFO if permitted).
1052 Check that the owner and permissions haven't changed.
1054 If file_format is set, check that the file still matches the format for
1055 the current transport. If not, defer delivery.
1057 (8f) If file does not exist initially:
1059 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1060 this is via a symbolic link (only possible if allow_symlinks is set), in
1061 which case don't use O_EXCL, as it doesn't work.
1063 If open fails because the file already exists, go to (6f). To avoid
1064 looping for ever in a situation where the file is continuously being
1065 created and deleted, all of this happens inside a loop that operates
1066 lock_retries times and includes the fcntl and flock locking. If the
1067 loop completes without the file getting opened, defer and request
1068 freezing, because something really weird is happening.
1070 If open fails for any other reason, defer for subsequent delivery except
1071 when this is a file delivery resulting from an alias or forward expansion
1072 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1073 most likely a user rather than a configuration error.
1075 (9f) We now have the file checked and open for writing. If so configured, lock
1076 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1077 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1078 still fails, give up and defer delivery.
1080 (10f)Save the access time (for subsequent restoration) and the size of the
1081 file, for comsat and for re-setting if delivery fails in the middle -
1082 e.g. for quota exceeded.
1084 The following items apply in the case when a directory name is given:
1086 (2d) Create a new file in the directory using a temporary name, by opening for
1087 writing and with O_CREAT. If maildir format is being used, the file
1088 is created in a temporary subdirectory with a prescribed name. If
1089 mailstore format is being used, the envelope file is first created with a
1090 temporary name, then the data file.
1092 The following items apply in all cases:
1094 (11) We now have the file open for writing, and locked if it was given as a
1095 file name. Write the message and flush the file, unless there is a setting
1096 of the local quota option, in which case we can check for its excession
1097 without doing any writing.
1099 In the case of MBX format mailboxes, the message is first written to a
1100 temporary file, in order to get its correct length. This is then copied to
1101 the real file, preceded by an MBX header.
1103 If there is a quota error on writing, defer the address. Timeout logic
1104 will determine for how long retries are attempted. We restore the mailbox
1105 to its original length if it's a single file. There doesn't seem to be a
1106 uniform error code for quota excession (it even differs between SunOS4
1107 and some versions of SunOS5) so a system-dependent macro called
1108 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1111 For any other error (most commonly disk full), do the same.
1113 The following applies after appending to a file:
1115 (12f)Restore the atime; notify_comsat if required; close the file (which
1116 unlocks it if it was locked). Delete the lock file if it exists.
1118 The following applies after writing a unique file in a directory:
1120 (12d)For maildir format, rename the file into the new directory. For mailstore
1121 format, rename the envelope file to its correct name. Otherwise, generate
1122 a unique name from the directory_file option, and rename to that, possibly
1123 trying a few times if the file exists and re-expanding the name gives a
1126 This transport yields FAIL only when a file name is generated by an alias or
1127 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1128 All other failures return DEFER (in addr->transport_return). */
1132 appendfile_transport_entry(
1133 transport_instance *tblock, /* data for this instantiation */
1134 address_item *addr) /* address we are working on */
1136 appendfile_transport_options_block *ob =
1137 (appendfile_transport_options_block *)(tblock->options_block);
1138 struct stat statbuf;
1139 const uschar * deliver_dir;
1140 uschar *fdname = NULL;
1141 uschar *filename = NULL;
1142 uschar *hitchname = NULL;
1143 uschar *dataname = NULL;
1144 uschar *lockname = NULL;
1145 uschar *newname = NULL;
1146 uschar *nametag = NULL;
1148 uschar *filecount_msg = US"";
1150 struct utimbuf times;
1151 struct timeval msg_tv;
1152 BOOL disable_quota = FALSE;
1153 BOOL isdirectory = FALSE;
1154 BOOL isfifo = FALSE;
1155 BOOL wait_for_tick = FALSE;
1156 uid_t uid = geteuid(); /* See note above */
1157 gid_t gid = getegid();
1159 int mode = (addr->mode > 0) ? addr->mode : ob->mode;
1160 off_t saved_size = -1;
1161 off_t mailbox_size = ob->mailbox_size_value;
1162 int mailbox_filecount = ob->mailbox_filecount_value;
1170 int mbx_lockfd = -1;
1171 uschar mbx_lockname[40];
1172 FILE *temp_file = NULL;
1173 #endif /* SUPPORT_MBX */
1175 #ifdef SUPPORT_MAILDIR
1176 int maildirsize_fd = -1; /* fd for maildirsize file */
1177 int maildir_save_errno;
1181 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1183 /* An "address_file" or "address_directory" transport is used to deliver to
1184 files specified via .forward or an alias file. Prior to release 4.20, the
1185 "file" and "directory" options were ignored in this case. This has been changed
1186 to allow the redirection data to specify what is in effect a folder, whose
1187 location is determined by the options on the transport.
1189 Compatibility with the case when neither option is set is retained by forcing a
1190 value for the file or directory name. A directory delivery is assumed if the
1191 last character of the path from the router is '/'.
1193 The file path is in the local part of the address, but not in the $local_part
1194 variable (that holds the parent local part). It is, however, in the
1195 $address_file variable. Below, we update the local part in the address if it
1196 changes by expansion, so that the final path ends up in the log. */
1198 if (testflag(addr, af_file) && !ob->filename && !ob->dirname)
1200 fdname = US"$address_file";
1201 if (address_file[Ustrlen(address_file)-1] == '/' ||
1202 ob->maildir_format ||
1203 ob->mailstore_format)
1207 /* Handle (a) an "address file" delivery where "file" or "directory" is
1208 explicitly set and (b) a non-address_file delivery, where one of "file" or
1209 "directory" must be set; initialization ensures that they are not both set. */
1213 if (!(fdname = ob->filename))
1215 fdname = ob->dirname;
1220 addr->message = string_sprintf("Mandatory file or directory option "
1221 "missing from %s transport", tblock->name);
1226 /* Maildir and mailstore require a directory */
1228 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1230 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1231 "to be specified for the %s transport",
1232 ob->maildir_format ? "dir" : "store", tblock->name);
1236 if (!(path = expand_string(fdname)))
1238 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1239 "name for %s transport) failed: %s", fdname, tblock->name,
1240 expand_string_message);
1246 addr->message = string_sprintf("appendfile: file or directory name "
1247 "\"%s\" is not absolute", path);
1248 addr->basic_errno = ERRNO_NOTABSOLUTE;
1252 /* For a file delivery, make sure the local part in the address(es) is updated
1253 to the true local part. */
1255 if (testflag(addr, af_file))
1256 for (address_item * addr2 = addr; addr2; addr2 = addr2->next)
1257 addr2->local_part = string_copy(path);
1259 /* The available mailbox formats depend on whether it is a directory or a file
1265 #ifdef SUPPORT_MAILDIR
1266 ob->maildir_format ? mbf_maildir :
1268 #ifdef SUPPORT_MAILSTORE
1269 ob->mailstore_format ? mbf_mailstore :
1277 ob->mbx_format ? mbf_mbx :
1284 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1286 " warning=" OFF_T_FMT "%s\n"
1287 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1288 "maildir_use_size_file=%s\n",
1289 mode, ob->notify_comsat, ob->quota_value,
1290 ob->quota_no_check ? " (no_check)" : "",
1291 ob->quota_filecount_no_check ? " (no_check_filecount)" : "",
1292 ob->quota_warn_threshold_value,
1293 ob->quota_warn_threshold_is_percent ? "%" : "",
1294 isdirectory ? "directory" : "file",
1295 path, mailbox_formats[mbformat],
1296 !ob->message_prefix ? US"null" : string_printing(ob->message_prefix),
1297 !ob->message_suffix ? US"null" : string_printing(ob->message_suffix),
1298 ob->maildir_use_size_file ? "yes" : "no");
1300 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1301 ob->use_lockfile ? "lockfile " : "",
1302 ob->use_mbx_lock ? "mbx locking (" : "",
1303 ob->use_fcntl ? "fcntl " : "",
1304 ob->use_flock ? "flock" : "",
1305 ob->use_mbx_lock ? ")" : "");
1308 /* If the -N option is set, can't do any more. */
1313 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1315 addr->transport_return = OK;
1319 /* If an absolute path was given for create_file the it overrides deliver_home
1320 (here) and de-taints the filename (below, after check_creation() */
1322 deliver_dir = *ob->create_file_string == '/'
1323 ? ob->create_file_string : deliver_home;
1325 /* Handle the case of a file name. If the file name is /dev/null, we can save
1326 ourselves some effort and just give a success return right away. */
1330 BOOL use_lstat = TRUE;
1331 BOOL file_opened = FALSE;
1332 BOOL allow_creation_here = TRUE;
1334 if (Ustrcmp(path, "/dev/null") == 0)
1336 addr->transport_return = OK;
1340 /* Set the name of the file to be opened, and the file to which the data
1341 is written, and find out if we are permitted to create a non-existent file.
1342 If the create_file option is an absolute path and the file was within it,
1343 de-taint. Chaeck for a tainted path. */
1345 if ( (allow_creation_here = check_creation(path, ob->create_file, deliver_dir))
1346 && ob->create_file == create_belowhome)
1347 if (is_tainted(path))
1349 DEBUG(D_transport) debug_printf("de-tainting path '%s'\n", path);
1350 path = string_copy_taint(path, GET_UNTAINTED);
1353 if (is_tainted(path)) goto tainted_ret_panic;
1354 dataname = filename = path;
1356 /* If ob->create_directory is set, attempt to create the directories in
1357 which this mailbox lives, but only if we are permitted to create the file
1358 itself. We know we are dealing with an absolute path, because this was
1361 if (ob->create_directory && allow_creation_here)
1363 uschar *p = Ustrrchr(path, '/');
1364 p = string_copyn(path, p - path);
1365 if (!directory_make(NULL, p, ob->dirmode, FALSE))
1367 addr->basic_errno = errno;
1369 string_sprintf("failed to create directories for %s: %s", path,
1370 exim_errstr(errno));
1371 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1376 /* If file_format is set we must check that any existing file matches one of
1377 the configured formats by checking the bytes it starts with. A match then
1378 indicates a specific transport - if it is not this one, pass control to it.
1379 Otherwise carry on here. An empty or non-existent file matches the current
1380 transport. We don't need to distinguish between non-existence and other open
1381 failures because if an existing file fails to open here, it will also fail
1382 again later when O_RDWR is used. */
1384 if (ob->file_format)
1386 int cfd = Uopen(path, O_RDONLY, 0);
1389 transport_instance *tt = check_file_format(cfd, tblock, addr);
1392 /* If another transport is indicated, call it and return; if no transport
1393 was found, just return - the error data will have been set up.*/
1399 set_process_info("delivering %s to %s using %s", message_id,
1400 addr->local_part, tt->name);
1401 debug_print_string(tt->debug_string);
1402 addr->transport = tt;
1403 (tt->info->code)(tt, addr);
1410 /* The locking of mailbox files is worse than the naming of cats, which is
1411 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1412 three different names, so several different styles of locking are used.
1414 Research in other programs that lock mailboxes shows that there is no
1415 universally standard method. Having mailboxes NFS-mounted on the system that
1416 is delivering mail is not the best thing, but people do run like this,
1417 and so the code must do its best to cope.
1419 Three different locking mechanisms are supported. The initialization function
1420 checks that at least one is configured.
1424 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1425 will work over NFS. Only after that is done do we actually open the mailbox
1426 and apply locks to it (if configured).
1428 Originally, Exim got the file opened before doing anything about locking.
1429 However, a very occasional problem was observed on Solaris 2 when delivering
1430 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1431 gets remembered at open time. If another process on another host (that's
1432 important) has the file open and locked and writes to it and then releases
1433 the lock while the first process is waiting to get the lock, the first
1434 process may fail to write at the new end point of the file - despite the very
1435 definite statement about O_APPEND in the man page for write(). Experiments
1436 have reproduced this problem, but I do not know any way of forcing a host to
1437 update its attribute cache for an open NFS file. It would be nice if it did
1438 so when a lock was taken out, but this does not seem to happen. Anyway, to
1439 reduce the risk of this problem happening, we now create the lock file
1440 (if configured) *before* opening the mailbox. That will prevent two different
1441 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1442 however, but Pine at least seems to operate in the same way.
1444 Lockfiles should normally be used when NFS is involved, because of the above
1447 The logic for creating the lock file is:
1449 . The name of the lock file is <mailbox-name>.lock
1451 . First, create a "hitching post" name by adding the primary host name,
1452 current time and pid to the lock file name. This should be unique.
1454 . Create the hitching post file using WRONLY + CREAT + EXCL.
1456 . If that fails EACCES, we assume it means that the user is unable to create
1457 files in the mail spool directory. Some installations might operate in this
1458 manner, so there is a configuration option to allow this state not to be an
1459 error - we proceed to lock using fcntl only, after the file is open.
1461 . Otherwise, an error causes a deferment of the address.
1463 . Hard link the hitching post to the lock file name.
1465 . If the link succeeds, we have successfully created the lock file. Simply
1466 close and unlink the hitching post file.
1468 . If the link does not succeed, proceed as follows:
1470 o Fstat the hitching post file, and then close and unlink it.
1472 o Now examine the stat data. If the number of links to the file is exactly
1473 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1474 the return never made it back, so the link() function gave a failure
1477 . This method allows for the lock file to be created by some other process
1478 right up to the moment of the attempt to hard link it, and is also robust
1479 against NFS server crash-reboots, which would probably result in timeouts
1480 in the middle of link().
1482 . System crashes may cause lock files to get left lying around, and some means
1483 of flushing them is required. The approach of writing a pid (used by smail
1484 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1485 timeout, which seems a better approach. Since any program that writes to a
1486 mailbox using a lock file should complete its task very quickly, Pine
1487 removes lock files that are older than 5 minutes. We allow the value to be
1488 configurable on the transport.
1492 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1493 mailbox once it is open. This is done by default with a non-blocking lock.
1494 Failures to lock cause retries after a sleep, but only for a certain number
1495 of tries. A blocking lock is deliberately not used so that we don't hold the
1496 mailbox open. This minimizes the possibility of the NFS problem described
1497 under LOCK FILES above, if for some reason NFS deliveries are happening
1498 without lock files. However, the use of a non-blocking lock and sleep, though
1499 the safest approach, does not give the best performance on very busy systems.
1500 A blocking lock plus timeout does better. Therefore Exim has an option to
1501 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1502 enables the use of blocking fcntl() calls.
1506 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1507 same manner as for fcntl locking above. No-blocking/timeout is also set as
1508 above in lock_flock_timeout. Not all operating systems provide or support
1509 flock(). For those that don't (as determined by the definition of LOCK_SH in
1510 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1511 is implemented (not precisely) on top of fcntl(), which means there's no
1512 point in actually using it.
1516 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1517 then the rules used for locking in c-client are used. Exim takes out a shared
1518 lock on the mailbox file, and an exclusive lock on the file whose name is
1519 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1520 any other MBX client from getting an exclusive lock on it and expunging it.
1521 It also stops any other MBX client from unlinking the /tmp lock when it has
1524 The exclusive lock on the /tmp file prevents any other MBX client from
1525 updating the mailbox in any way. When writing is finished, if an exclusive
1526 lock on the mailbox can be obtained, indicating there are no current sharers,
1527 the /tmp file is unlinked.
1529 MBX locking can use either fcntl() or flock() locking. If neither
1530 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1531 The calls for getting these locks are by default non-blocking, as for non-mbx
1532 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1533 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1534 probably makes sense to set timeouts for any MBX deliveries. */
1537 /* Build a lock file if configured to do so - the existence of a lock
1538 file is subsequently checked by looking for a non-negative value of the
1539 file descriptor hd - even though the file is no longer open. */
1541 if (ob->use_lockfile)
1543 /* cf. exim_lock.c */
1544 lockname = string_sprintf("%s.lock", filename);
1545 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1546 (unsigned int)(time(NULL)), (unsigned int)getpid());
1548 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1551 /* Lock file creation retry loop */
1553 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1557 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1560 addr->basic_errno = errno;
1562 string_sprintf("creating lock file hitching post %s "
1563 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1564 (long int)getegid());
1568 /* Attempt to hitch the hitching post to the lock file. If link()
1569 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1570 file, and get rid of the hitching post. If the number of links was 2,
1571 the link was created, despite the failure of link(). If the hitch was
1572 not successful, try again, having unlinked the lock file if it is too
1575 There's a version of Linux (2.0.27) which doesn't update its local cache
1576 of the inode after link() by default - which many think is a bug - but
1577 if the link succeeds, this code will be OK. It just won't work in the
1578 case when link() fails after having actually created the link. The Linux
1579 NFS person is fixing this; a temporary patch is available if anyone is
1580 sufficiently worried. */
1582 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1585 if (rc != 0 && statbuf.st_nlink != 2)
1587 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1588 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1590 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1593 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1597 DEBUG(D_transport) debug_printf("lock file created\n");
1601 /* Check for too many tries at creating the lock file */
1603 if (i >= ob->lock_retries)
1605 addr->basic_errno = ERRNO_LOCKFAILED;
1606 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1613 /* We now have to get the file open. First, stat() it and act on existence or
1614 non-existence. This is in a loop to handle the case of a file's being created
1615 or deleted as we watch, and also to handle retries when the locking fails.
1616 Rather than holding the file open while waiting for the fcntl() and/or
1617 flock() lock, we close and do the whole thing again. This should be safer,
1618 especially for NFS files, which might get altered from other hosts, making
1619 their cached sizes incorrect.
1621 With the default settings, no symlinks are permitted, but there is an option
1622 to permit symlinks for those sysadmins that know what they are doing.
1623 Shudder. However, insist that the initial symlink is owned by the right user.
1624 Thus lstat() is used initially; if a symlink is discovered, the loop is
1625 repeated such that stat() is used, to look at the end file. */
1627 for (i = 0; i < ob->lock_retries; i++)
1629 int sleep_before_retry = TRUE;
1630 file_opened = FALSE;
1632 if ((use_lstat ? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1634 /* Let's hope that failure to stat (other than non-existence) is a
1637 if (errno != ENOENT)
1639 addr->basic_errno = errno;
1640 addr->message = string_sprintf("attempting to stat mailbox %s",
1645 /* File does not exist. If it is required to pre-exist this state is an
1648 if (ob->file_must_exist)
1650 addr->basic_errno = errno;
1651 addr->message = string_sprintf("mailbox %s does not exist, "
1652 "but file_must_exist is set", filename);
1656 /* If not permitted to create this file because it isn't in or below
1657 the home directory, generate an error. */
1659 if (!allow_creation_here)
1661 addr->basic_errno = ERRNO_BADCREATE;
1662 addr->message = string_sprintf("mailbox %s does not exist, "
1663 "but creation outside the home directory is not permitted",
1668 /* Attempt to create and open the file. If open fails because of
1669 pre-existence, go round the loop again. For any other error, defer the
1670 address, except for an alias or forward generated file name with EPERM,
1671 ENOENT, or EACCES, as those are most likely to be user errors rather
1672 than Exim config errors. When a symbolic link is permitted and points
1673 to a non-existent file, we get here with use_lstat = FALSE. In this case
1674 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1675 consistency and because MBX locking requires it in order to be able to
1676 get a shared lock. */
1678 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1679 (use_lstat ? O_EXCL : 0), mode);
1682 if (errno == EEXIST) continue;
1683 addr->basic_errno = errno;
1684 addr->message = string_sprintf("while creating mailbox %s",
1686 if (testflag(addr, af_file) &&
1687 (errno == EPERM || errno == ENOENT || errno == EACCES))
1688 addr->transport_return = FAIL;
1692 /* We have successfully created and opened the file. Ensure that the group
1693 and the mode are correct. */
1695 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
1697 addr->basic_errno = errno;
1698 addr->message = string_sprintf("while setting perms on mailbox %s",
1700 addr->transport_return = FAIL;
1706 /* The file already exists. Test its type, ownership, and permissions, and
1707 save the inode for checking later. If symlinks are permitted (not the
1708 default or recommended state) it may be a symlink that already exists.
1709 Check its ownership and then look for the file at the end of the link(s).
1710 This at least prevents one user creating a symlink for another user in
1711 a sticky directory. */
1715 int oldmode = (int)statbuf.st_mode;
1716 ino_t inode = statbuf.st_ino;
1717 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1719 isfifo = FALSE; /* In case things are changing */
1721 /* Check owner if required - the default. */
1723 if (ob->check_owner && statbuf.st_uid != uid)
1725 addr->basic_errno = ERRNO_BADUGID;
1726 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1727 "(%ld != %ld)", filename,
1728 islink ? " (symlink)" : "",
1729 (long int)(statbuf.st_uid), (long int)uid);
1733 /* Group is checked only if check_group is set. */
1735 if (ob->check_group && statbuf.st_gid != gid)
1737 addr->basic_errno = ERRNO_BADUGID;
1738 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1739 filename, islink ? " (symlink)" : "", statbuf.st_gid, gid);
1743 /* Just in case this is a sticky-bit mail directory, we don't want
1744 users to be able to create hard links to other users' files. */
1746 if (statbuf.st_nlink != 1)
1748 addr->basic_errno = ERRNO_NOTREGULAR;
1749 addr->message = string_sprintf("mailbox %s%s has too many links (%lu)",
1750 filename, islink ? " (symlink)" : "", (unsigned long)statbuf.st_nlink);
1755 /* If symlinks are permitted (not recommended), the lstat() above will
1756 have found the symlink. Its ownership has just been checked; go round
1757 the loop again, using stat() instead of lstat(). That will never yield a
1760 if (islink && ob->allow_symlink)
1763 i--; /* Don't count this time round */
1767 /* An actual file exists. Check that it is a regular file, or FIFO
1770 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1772 else if ((oldmode & S_IFMT) != S_IFREG)
1774 addr->basic_errno = ERRNO_NOTREGULAR;
1775 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1776 filename, ob->allow_fifo ? " or named pipe" : "");
1780 /* If the mode is not what it would be for a newly created file, change
1781 the permissions if the mode is supplied for the address. Otherwise,
1782 reduce but do not extend the permissions. If the newly created
1783 permissions are greater than the existing permissions, don't change
1784 things when the mode is not from the address. */
1786 if ((oldmode &= 07777) != mode)
1788 int diffs = oldmode ^ mode;
1789 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1791 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1792 if (Uchmod(filename, mode) < 0)
1794 addr->basic_errno = errno;
1795 addr->message = string_sprintf("attempting to chmod mailbox %s",
1802 /* Mode not from address, and newly-created permissions are greater
1803 than existing permissions. Default is to complain, but it can be
1804 configured to go ahead and try to deliver anyway if that's what
1805 the administration wants. */
1807 else if (ob->mode_fail_narrower)
1809 addr->basic_errno = ERRNO_BADMODE;
1810 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1811 "(%o expected)", filename, oldmode, mode);
1816 /* We are happy with the existing file. Open it, and then do further
1817 tests to ensure that it is the same file that we were just looking at.
1818 If the file does not now exist, restart this loop, going back to using
1819 lstat again. For an NFS error, just defer; other opening errors are
1820 more serious. The file is opened RDWR so that its format can be checked,
1821 and also MBX locking requires the use of a shared (read) lock. However,
1822 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1823 reading the pipe. */
1825 fd = Uopen(filename, isfifo ? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1829 if (errno == ENOENT)
1834 addr->basic_errno = errno;
1836 addr->message = string_sprintf("while opening named pipe %s "
1837 "(could mean no process is reading it)", filename);
1838 else if (errno != EWOULDBLOCK)
1839 addr->message = string_sprintf("while opening mailbox %s", filename);
1843 /* This fstat really shouldn't fail, as we have an open file! There's a
1844 dilemma here. We use fstat in order to be sure we are peering at the file
1845 we have got open. However, that won't tell us if the file was reached
1846 via a symbolic link. We checked this above, but there is a race exposure
1847 if the link was created between the previous lstat and the open. However,
1848 it would have to be created with the same inode in order to pass the
1849 check below. If ob->allow_symlink is set, causing the use of stat rather
1850 than lstat above, symbolic links may be there anyway, and the checking is
1853 if (fstat(fd, &statbuf) < 0)
1855 addr->basic_errno = errno;
1856 addr->message = string_sprintf("attempting to stat open mailbox %s",
1861 /* Check the inode; this is isn't a perfect check, but gives some
1864 if (inode != statbuf.st_ino)
1866 addr->basic_errno = ERRNO_INODECHANGED;
1867 addr->message = string_sprintf("opened mailbox %s inode number changed "
1868 "from " INO_T_FMT " to " INO_T_FMT, filename, inode, statbuf.st_ino);
1869 addr->special_action = SPECIAL_FREEZE;
1873 /* Check it's still a regular file or FIFO, and the uid, gid, and
1874 permissions have not changed. */
1876 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1877 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1879 addr->basic_errno = ERRNO_NOTREGULAR;
1881 string_sprintf("opened mailbox %s is no longer a %s", filename,
1882 isfifo ? "named pipe" : "regular file");
1883 addr->special_action = SPECIAL_FREEZE;
1887 if ((ob->check_owner && statbuf.st_uid != uid) ||
1888 (ob->check_group && statbuf.st_gid != gid))
1890 addr->basic_errno = ERRNO_BADUGID;
1892 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
1893 addr->special_action = SPECIAL_FREEZE;
1897 if ((statbuf.st_mode & 07777) != oldmode)
1899 addr->basic_errno = ERRNO_BADMODE;
1900 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
1901 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
1902 addr->special_action = SPECIAL_FREEZE;
1906 /* If file_format is set, check that the format of the file has not
1907 changed. Error data is set by the testing function. */
1909 if (ob->file_format && check_file_format(fd, tblock, addr) != tblock)
1911 addr->message = US"open mailbox has changed format";
1915 /* The file is OK. Carry on to do the locking. */
1918 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
1919 locking rules if configured to do so. If a lock file is also required, it
1920 was created above and hd was left >= 0. At least one form of locking is
1921 required by the initialization function. If locking fails here, close the
1922 file and go round the loop all over again, after waiting for a bit, unless
1923 blocking locking was used. */
1926 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
1927 sleep_before_retry = FALSE;
1929 /* Simple fcntl() and/or flock() locking */
1931 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
1933 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1934 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
1937 /* MBX locking rules */
1940 else if (ob->use_mbx_lock)
1943 struct stat lstatbuf, statbuf2;
1944 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1945 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
1946 fstat(fd, &statbuf) >= 0)
1948 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
1949 (long)statbuf.st_ino);
1952 * 2010-05-29: SECURITY
1953 * Dan Rosenberg reported the presence of a race-condition in the
1954 * original code here. Beware that many systems still allow symlinks
1955 * to be followed in /tmp so an attacker can create a symlink pointing
1956 * elsewhere between a stat and an open, which we should avoid
1959 * It's unfortunate that we can't just use all the heavily debugged
1960 * locking from above.
1962 * Also: remember to mirror changes into exim_lock.c */
1964 /* first leave the old pre-check in place, it provides better
1965 * diagnostics for common cases */
1966 if (Ulstat(mbx_lockname, &statbuf) >= 0)
1968 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
1970 addr->basic_errno = ERRNO_LOCKFAILED;
1971 addr->message = string_sprintf("symbolic link on MBX lock file %s",
1975 if (statbuf.st_nlink > 1)
1977 addr->basic_errno = ERRNO_LOCKFAILED;
1978 addr->message = string_sprintf("hard link to MBX lock file %s",
1984 /* If we could just declare "we must be the ones who create this
1985 * file" then a hitching post in a subdir would work, since a
1986 * subdir directly in /tmp/ which we create wouldn't follow links
1987 * but this isn't our locking logic, so we can't safely change the
1988 * file existence rules. */
1990 /* On systems which support O_NOFOLLOW, it's the easiest and most
1991 * obviously correct security fix */
1992 mbx_tmp_oflags = O_RDWR | O_CREAT;
1994 mbx_tmp_oflags |= O_NOFOLLOW;
1996 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
1999 addr->basic_errno = ERRNO_LOCKFAILED;
2000 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2001 mbx_lockname, strerror(errno));
2005 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2007 addr->basic_errno = ERRNO_LOCKFAILED;
2008 addr->message = string_sprintf("attempting to lstat open MBX "
2009 "lock file %s: %s", mbx_lockname, strerror(errno));
2012 if (fstat(mbx_lockfd, &statbuf2) < 0)
2014 addr->basic_errno = ERRNO_LOCKFAILED;
2015 addr->message = string_sprintf("attempting to stat fd of open MBX "
2016 "lock file %s: %s", mbx_lockname, strerror(errno));
2022 * statbuf: if exists, is file which existed prior to opening the
2023 * lockfile, might have been replaced since then
2024 * statbuf2: result of stat'ing the open fd, is what was actually
2026 * lstatbuf: result of lstat'ing the filename immediately after
2027 * the open but there's a race condition again between
2028 * those two steps: before open, symlink to foo, after
2029 * open but before lstat have one of:
2030 * * was no symlink, so is the opened file
2031 * (we created it, no messing possible after that point)
2033 * * symlink elsewhere
2034 * * hardlink elsewhere
2036 * Don't want to compare to device of /tmp because some modern systems
2037 * have regressed to having /tmp be the safe actual filesystem as
2038 * valuable data, so is mostly worthless, unless we assume that *only*
2039 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2040 * for further consideration.
2041 * No point in doing a readlink on the lockfile as that will always be
2042 * at a different point in time from when we open it, so tells us
2043 * nothing; attempts to clean up and delete after ourselves would risk
2044 * deleting a *third* filename.
2046 if ((statbuf2.st_nlink > 1) ||
2047 (lstatbuf.st_nlink > 1) ||
2048 (!S_ISREG(lstatbuf.st_mode)) ||
2049 (lstatbuf.st_dev != statbuf2.st_dev) ||
2050 (lstatbuf.st_ino != statbuf2.st_ino))
2052 addr->basic_errno = ERRNO_LOCKFAILED;
2053 addr->message = string_sprintf("RACE CONDITION detected: "
2054 "mismatch post-initial-checks between \"%s\" and opened "
2055 "fd lead us to abort!", mbx_lockname);
2059 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2061 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2062 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2064 struct stat ostatbuf;
2066 /* This tests for a specific race condition. Ensure that we still
2067 have the same file. */
2069 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2070 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2071 statbuf.st_dev == ostatbuf.st_dev &&
2072 statbuf.st_ino == ostatbuf.st_ino)
2074 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2075 "between creation and locking\n", mbx_lockname);
2078 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2080 (void)close(mbx_lockfd);
2085 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2086 filename, strerror(errno));
2089 #endif /* SUPPORT_MBX */
2091 else break; /* No on-file locking required; break the open/lock loop */
2094 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2098 use_lstat = TRUE; /* Reset to use lstat first */
2101 /* If a blocking call timed out, break the retry loop if the total time
2102 so far is not less than than retries * interval. Use the larger of the
2103 flock() and fcntl() timeouts. */
2106 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2107 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2108 ob->lock_retries * ob->lock_interval)
2109 i = ob->lock_retries;
2111 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2112 flock() that caused the problem. */
2114 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2117 /* Test for exceeding the maximum number of tries. Either the file remains
2118 locked, or, if we haven't got it open, something is terribly wrong... */
2120 if (i >= ob->lock_retries)
2124 addr->basic_errno = ERRNO_EXISTRACE;
2125 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2126 addr->special_action = SPECIAL_FREEZE;
2130 addr->basic_errno = ERRNO_LOCKFAILED;
2131 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2137 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2139 /* Save access time (for subsequent restoration), modification time (for
2140 restoration if updating fails), size of file (for comsat and for re-setting if
2141 delivery fails in the middle - e.g. for quota exceeded). */
2143 if (fstat(fd, &statbuf) < 0)
2145 addr->basic_errno = errno;
2146 addr->message = string_sprintf("while fstatting opened mailbox %s",
2151 times.actime = statbuf.st_atime;
2152 times.modtime = statbuf.st_mtime;
2153 saved_size = statbuf.st_size;
2154 if (mailbox_size < 0) mailbox_size = saved_size;
2155 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2158 /* Prepare for writing to a new file (as opposed to appending to an old one).
2159 There are several different formats, but there is preliminary stuff concerned
2160 with quotas that applies to all of them. Finding the current size by directory
2161 scanning is expensive; for maildirs some fudges have been invented:
2163 (1) A regex can be used to extract a file size from its name;
2164 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2170 uschar *check_path; /* Default quota check path */
2171 const pcre2_code * re = NULL; /* Regex for file size from file name */
2173 if (!check_creation(string_sprintf("%s/any", path),
2174 ob->create_file, deliver_dir))
2176 addr->basic_errno = ERRNO_BADCREATE;
2177 addr->message = string_sprintf("tried to create file in %s, but "
2178 "file creation outside the home directory is not permitted", path);
2182 /* If the create_file option is an absolute path and the file was within
2183 it, de-taint. Otherwise check for taint. */
2185 if (is_tainted(path))
2186 if (ob->create_file == create_belowhome)
2188 DEBUG(D_transport) debug_printf("de-tainting path '%s'\n", path);
2189 path = string_copy_taint(path, GET_UNTAINTED);
2192 goto tainted_ret_panic;
2196 #ifdef SUPPORT_MAILDIR
2197 /* For a maildir delivery, ensure that all the relevant directories exist,
2198 and a maildirfolder file if necessary. */
2200 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2201 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2203 #endif /* SUPPORT_MAILDIR */
2205 /* If we are going to do a quota check, of if maildir_use_size_file is set
2206 for a maildir delivery, compile the regular expression if there is one. We
2207 may also need to adjust the path that is used. We need to do this for
2208 maildir_use_size_file even if the quota is unset, because we still want to
2209 create the file. When maildir support is not compiled,
2210 ob->maildir_use_size_file is always FALSE. */
2212 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2217 /* Compile the regex if there is one. */
2219 if (ob->quota_size_regex)
2221 if (!(re = pcre2_compile((PCRE2_SPTR)ob->quota_size_regex,
2222 PCRE2_ZERO_TERMINATED, PCRE_COPT, &err, &offset, pcre_cmp_ctx)))
2225 pcre2_get_error_message(err, errbuf, sizeof(errbuf));
2226 addr->message = string_sprintf("appendfile: regular expression "
2227 "error: %s at offset %ld while compiling %s", errbuf, (long)offset,
2228 ob->quota_size_regex);
2231 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2232 ob->quota_size_regex);
2235 /* Use an explicitly configured directory if set */
2237 if (ob->quota_directory)
2239 if (!(check_path = expand_string(ob->quota_directory)))
2241 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2242 "name for %s transport) failed: %s", ob->quota_directory,
2243 tblock->name, expand_string_message);
2247 if (check_path[0] != '/')
2249 addr->message = string_sprintf("appendfile: quota_directory name "
2250 "\"%s\" is not absolute", check_path);
2251 addr->basic_errno = ERRNO_NOTABSOLUTE;
2256 #ifdef SUPPORT_MAILDIR
2257 /* Otherwise, if we are handling a maildir delivery, and the directory
2258 contains a file called maildirfolder, this is a maildir++ feature telling
2259 us that this is a sub-directory of the real inbox. We should therefore do
2260 the quota check on the parent directory. Beware of the special case when
2261 the directory name itself ends in a slash. */
2263 else if (mbformat == mbf_maildir)
2265 struct stat statbuf;
2266 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2268 uschar *new_check_path = string_copy(check_path);
2269 uschar *slash = Ustrrchr(new_check_path, '/');
2275 slash = Ustrrchr(new_check_path, '/');
2280 check_path = new_check_path;
2281 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2282 "quota check directory changed to %s\n", check_path);
2287 #endif /* SUPPORT_MAILDIR */
2290 /* If we are using maildirsize files, we need to ensure that such a file
2291 exists and, if necessary, recalculate its contents. As a byproduct of this,
2292 we obtain the current size of the maildir. If no quota is to be enforced
2293 (ob->quota_value == 0), we still need the size if a threshold check will
2296 Another regular expression is used to determine which directories inside the
2297 maildir are going to be counted. */
2299 #ifdef SUPPORT_MAILDIR
2300 if (ob->maildir_use_size_file)
2302 const pcre2_code * dir_regex = NULL;
2306 if (ob->maildir_dir_regex)
2308 int check_path_len = Ustrlen(check_path);
2310 if (!(dir_regex = pcre2_compile((PCRE2_SPTR)ob->maildir_dir_regex,
2311 PCRE2_ZERO_TERMINATED, PCRE_COPT, &err, &offset, pcre_cmp_ctx)))
2314 pcre2_get_error_message(err, errbuf, sizeof(errbuf));
2315 addr->message = string_sprintf("appendfile: regular expression "
2316 "error: %s at offset %ld while compiling %s", errbuf, (long)offset,
2317 ob->maildir_dir_regex);
2322 debug_printf("using regex for maildir directory selection: %s\n",
2323 ob->maildir_dir_regex);
2325 /* Check to see if we are delivering into an ignored directory, that is,
2326 if the delivery path starts with the quota check path, and the rest
2327 of the deliver path matches the regex; if so, set a flag to disable quota
2328 checking and maildirsize updating. */
2330 if (Ustrncmp(path, check_path, check_path_len) == 0)
2332 uschar *s = path + check_path_len;
2333 while (*s == '/') s++;
2334 s = *s ? string_sprintf("%s/new", s) : US"new";
2335 if (!regex_match(dir_regex, s, -1, NULL))
2337 disable_quota = TRUE;
2338 DEBUG(D_transport) debug_printf("delivery directory does not match "
2339 "maildir_quota_directory_regex: disabling quota\n");
2344 /* Quota enforcement; create and check the file. There is some discussion
2345 about whether this should happen if the quota is unset. At present, Exim
2346 always creates the file. If we ever want to change this, uncomment
2347 appropriate lines below, possibly doing a check on some option. */
2349 /* if (???? || ob->quota_value > 0) */
2356 if ((maildirsize_fd = maildir_ensure_sizefile(check_path, ob, re, dir_regex,
2357 &size, &filecount)) == -1)
2359 addr->basic_errno = errno;
2360 addr->message = string_sprintf("while opening or reading "
2361 "%s/maildirsize", check_path);
2364 /* can also return -2, which means that the file was removed because of
2365 raciness; but in this case, the size & filecount will still have been
2368 if (mailbox_size < 0) mailbox_size = size;
2369 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2372 /* No quota enforcement; ensure file does *not* exist; calculate size if
2377 * time_t old_latest;
2378 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2379 * if (THRESHOLD_CHECK)
2380 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2381 * re, dir_regex, FALSE);
2386 #endif /* SUPPORT_MAILDIR */
2388 /* Otherwise if we are going to do a quota check later on, and the mailbox
2389 size is not set, find the current size of the mailbox. Ditto for the file
2390 count. Note that ob->quota_filecount_value cannot be set without
2391 ob->quota_value being set. */
2394 && (ob->quota_value > 0 || THRESHOLD_CHECK)
2395 && ( mailbox_size < 0
2396 || mailbox_filecount < 0 && ob->quota_filecount_value > 0
2402 debug_printf("quota checks on directory %s\n", check_path);
2403 size = check_dir_size(check_path, &filecount, re);
2404 if (mailbox_size < 0) mailbox_size = size;
2405 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2408 /* Handle the case of creating a unique file in a given directory (not in
2409 maildir or mailstore format - this is how smail did it). A temporary name is
2410 used to create the file. Later, when it is written, the name is changed to a
2411 unique one. There is no need to lock the file. An attempt is made to create
2412 the directory if it does not exist. */
2414 if (mbformat == mbf_smail)
2417 debug_printf("delivering to new file in %s\n", path);
2418 filename = dataname =
2419 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2420 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2421 if (fd < 0 && /* failed to open, and */
2422 (errno != ENOENT || /* either not non-exist */
2423 !ob->create_directory || /* or not allowed to make */
2424 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2425 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2427 addr->basic_errno = errno;
2428 addr->message = string_sprintf("while creating file %s", filename);
2433 #ifdef SUPPORT_MAILDIR
2435 /* Handle the case of a unique file in maildir format. The file is written to
2436 the tmp subdirectory, with a prescribed form of name. */
2438 else if (mbformat == mbf_maildir)
2441 debug_printf("delivering in maildir format in %s\n", path);
2443 nametag = ob->maildir_tag;
2445 /* Check that nametag expands successfully; a hard failure causes a panic
2446 return. The actual expansion for use happens again later, when
2447 $message_size is accurately known. */
2449 if (nametag && !expand_string(nametag) && !f.expand_string_forcedfail)
2451 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2452 "for %s transport) failed: %s", nametag, tblock->name,
2453 expand_string_message);
2457 /* We ensured the existence of all the relevant directories above. Attempt
2458 to open the temporary file a limited number of times. I think this rather
2459 scary-looking for statement is actually OK. If open succeeds, the loop is
2460 broken; if not, there is a test on the value of i. Get the time again
2461 afresh each time round the loop. Its value goes into a variable that is
2462 checked at the end, to make sure we don't release this process until the
2463 clock has ticked. */
2465 for (int i = 1;; i++)
2469 (void)gettimeofday(&msg_tv, NULL);
2470 basename = string_sprintf(TIME_T_FMT ".M%luP" PID_T_FMT ".%s",
2471 msg_tv.tv_sec, msg_tv.tv_usec, getpid(), primary_hostname);
2473 filename = dataname = string_sprintf("tmp/%s", basename);
2474 newname = string_sprintf("new/%s", basename);
2476 if (Ustat(filename, &statbuf) == 0)
2478 else if (errno == ENOENT)
2480 if ((fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode)) >= 0)
2482 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2483 filename, strerror(errno));
2486 /* Too many retries - give up */
2488 if (i >= ob->maildir_retries)
2490 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2491 filename, i, (i == 1) ? "y" : "ies");
2492 addr->basic_errno = errno;
2493 if (errno == errno_quota || errno == ENOSPC)
2494 addr->user_message = US"mailbox is full";
2498 /* Open or stat failed but we haven't tried too many times yet. */
2503 /* Note that we have to ensure the clock has ticked before leaving */
2505 wait_for_tick = TRUE;
2507 /* Why are these here? Put in because they are present in the non-maildir
2508 directory case above. */
2510 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2512 addr->basic_errno = errno;
2513 addr->message = string_sprintf("while setting perms on maildir %s",
2519 #endif /* SUPPORT_MAILDIR */
2521 #ifdef SUPPORT_MAILSTORE
2523 /* Handle the case of a unique file in mailstore format. First write the
2524 envelope to a temporary file, then open the main file. The unique base name
2525 for the files consists of the message id plus the pid of this delivery
2531 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2532 string_base62((long int)getpid()));
2535 debug_printf("delivering in mailstore format in %s\n", path);
2537 filename = string_sprintf("%s.tmp", mailstore_basename);
2538 newname = string_sprintf("%s.env", mailstore_basename);
2539 dataname = string_sprintf("%s.msg", mailstore_basename);
2541 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2542 if ( fd < 0 /* failed to open, and */
2543 && ( errno != ENOENT /* either not non-exist */
2544 || !ob->create_directory /* or not allowed to make */
2545 || !directory_make(NULL, path, ob->dirmode, FALSE) /* or failed to create dir */
2546 || (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0 /* or then failed to open */
2549 addr->basic_errno = errno;
2550 addr->message = string_sprintf("while creating file %s", filename);
2554 /* Why are these here? Put in because they are present in the non-maildir
2555 directory case above. */
2557 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2559 addr->basic_errno = errno;
2560 addr->message = string_sprintf("while setting perms on file %s",
2565 /* Built a C stream from the open file descriptor. */
2567 if (!(env_file = fdopen(fd, "wb")))
2569 addr->basic_errno = errno;
2570 addr->message = string_sprintf("fdopen of %s ("
2571 "for %s transport) failed", filename, tblock->name);
2577 /* Write the envelope file, then close it. */
2579 if (ob->mailstore_prefix)
2581 uschar *s = expand_string(ob->mailstore_prefix);
2584 if (!f.expand_string_forcedfail)
2586 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2587 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2588 tblock->name, expand_string_message);
2589 (void)fclose(env_file);
2597 fprintf(env_file, "%s", CS s);
2598 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2602 fprintf(env_file, "%s\n", sender_address);
2604 for (address_item * taddr = addr; taddr; taddr = taddr->next)
2605 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2607 if (ob->mailstore_suffix)
2609 uschar *s = expand_string(ob->mailstore_suffix);
2612 if (!f.expand_string_forcedfail)
2614 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2615 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2616 tblock->name, expand_string_message);
2617 (void)fclose(env_file);
2625 fprintf(env_file, "%s", CS s);
2626 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2630 if (fclose(env_file) != 0)
2632 addr->basic_errno = errno;
2633 addr->message = string_sprintf("while closing %s", filename);
2638 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2640 /* Now open the data file, and ensure that it has the correct ownership and
2643 if ((fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)
2645 addr->basic_errno = errno;
2646 addr->message = string_sprintf("while creating file %s", dataname);
2650 if (exim_chown(dataname, uid, gid) || Uchmod(dataname, mode))
2652 addr->basic_errno = errno;
2653 addr->message = string_sprintf("while setting perms on file %s",
2659 #endif /* SUPPORT_MAILSTORE */
2662 /* In all cases of writing to a new file, ensure that the file which is
2663 going to be renamed has the correct ownership and mode. */
2665 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2667 addr->basic_errno = errno;
2668 addr->message = string_sprintf("while setting perms on file %s",
2675 /* At last we can write the message to the file, preceded by any configured
2676 prefix line, and followed by any configured suffix line. If there are any
2677 writing errors, we must defer. */
2679 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2684 /* If there is a local quota setting, check that we are not going to exceed it
2685 with this message if quota_is_inclusive is set; if it is not set, the check
2686 is for the mailbox already being over quota (i.e. the current message is not
2687 included in the check). */
2689 if (!disable_quota && ob->quota_value > 0)
2693 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2694 " this message = %d (%sincluded)\n",
2695 ob->quota_value, mailbox_size, message_size,
2696 ob->quota_is_inclusive ? "" : "not ");
2697 debug_printf(" file count quota = %d count = %d\n",
2698 ob->quota_filecount_value, mailbox_filecount);
2701 if (mailbox_size + (ob->quota_is_inclusive ? message_size:0) > ob->quota_value)
2702 if (!ob->quota_no_check)
2704 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2706 errno = ERRNO_EXIMQUOTA;
2709 DEBUG(D_transport) debug_printf("mailbox quota exceeded but ignored\n");
2711 if (ob->quota_filecount_value > 0
2712 && mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2713 ob->quota_filecount_value)
2714 if (!ob->quota_filecount_no_check)
2716 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2718 errno = ERRNO_EXIMQUOTA;
2719 filecount_msg = US" filecount";
2721 else DEBUG(D_transport) if (ob->quota_filecount_no_check)
2722 debug_printf("mailbox file count quota exceeded but ignored\n");
2728 addr->basic_errno = errno;
2729 addr->message = US"Over quota";
2730 addr->transport_return = yield;
2732 debug_printf("appendfile (verify) yields %d with errno=%d more_errno=%d\n",
2733 yield, addr->basic_errno, addr->more_errno);
2738 /* If we are writing in MBX format, what we actually do is to write the message
2739 to a temporary file, and then copy it to the real file once we know its size.
2740 This is the most straightforward way of getting the correct length in the
2741 separator line. So, what we do here is to save the real file descriptor, and
2742 replace it with one for a temporary file. The temporary file gets unlinked once
2743 opened, so that it goes away on closure. */
2746 if (yield == OK && ob->mbx_format)
2748 if (!(temp_file = tmpfile()))
2750 addr->basic_errno = errno;
2751 addr->message = US"while setting up temporary file";
2756 fd = fileno(temp_file);
2757 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2759 #endif /* SUPPORT_MBX */
2761 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2764 transport_count = 0;
2765 transport_newlines = 0;
2767 /* Write any configured prefix text first */
2769 if (yield == OK && ob->message_prefix && *ob->message_prefix)
2771 uschar *prefix = expand_string(ob->message_prefix);
2774 errno = ERRNO_EXPANDFAIL;
2775 addr->transport_return = PANIC;
2776 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2777 "transport) failed", ob->message_prefix, tblock->name);
2780 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2783 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2784 various different values for batching are handled outside; if there is more
2785 than one address available here, all must be included. If any address is a
2786 file, use its parent in the RCPT TO. */
2788 if (yield == OK && ob->use_bsmtp)
2790 transport_count = 0;
2791 transport_newlines = 0;
2792 if (ob->use_crlf) cr = US"\r";
2793 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2797 transport_newlines++;
2798 for (address_item * a = addr; a; a = a->next)
2800 address_item * b = testflag(a, af_pfr) ? a->parent : a;
2801 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2802 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2803 { yield = DEFER; break; }
2804 transport_newlines++;
2806 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2809 transport_newlines++;
2813 /* Now the message itself. The options for transport_write_message were set up
2814 at initialization time. */
2818 transport_ctx tctx = {
2822 .check_string = ob->check_string,
2823 .escape_string = ob->escape_string,
2824 .options = ob->options | topt_not_socket
2826 if (!transport_write_message(&tctx, 0))
2830 /* Now a configured suffix. */
2832 if (yield == OK && ob->message_suffix && *ob->message_suffix)
2834 uschar *suffix = expand_string(ob->message_suffix);
2837 errno = ERRNO_EXPANDFAIL;
2838 addr->transport_return = PANIC;
2839 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2840 "transport) failed", ob->message_suffix, tblock->name);
2843 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2846 /* If batch smtp, write the terminating dot. */
2848 if (yield == OK && ob->use_bsmtp)
2849 if (!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2850 else transport_newlines++;
2852 /* If MBX format is being used, all that writing was to the temporary file.
2853 However, if there was an earlier failure (Exim quota exceeded, for example),
2854 the temporary file won't have got opened - and no writing will have been done.
2855 If writing was OK, we restore the fd, and call a function that copies the
2856 message in MBX format into the real file. Otherwise use the temporary name in
2860 if (temp_file && ob->mbx_format)
2867 transport_count = 0; /* Reset transport count for actual write */
2868 /* No need to reset transport_newlines as we're just using a block copy
2869 * routine so the number won't be affected */
2870 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2872 else if (errno >= 0) dataname = US"temporary file";
2874 /* Preserve errno while closing the temporary file. */
2876 mbx_save_errno = errno;
2877 (void)fclose(temp_file);
2878 errno = mbx_save_errno;
2880 #endif /* SUPPORT_MBX */
2882 /* Force out the remaining data to check for any errors; some OS don't allow
2883 fsync() to be called for a FIFO. */
2885 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2887 /* Update message_size and message_linecount to the accurate count of bytes
2888 written, including added headers. Note; we subtract 1 from message_linecount as
2889 this variable doesn't count the new line between the header and the body of the
2892 message_size = transport_count;
2893 message_linecount = transport_newlines - 1;
2895 /* If using a maildir++ quota file, add this message's size to it, and
2896 close the file descriptor, except when the quota has been disabled because we
2897 are delivering into an uncounted folder. */
2899 #ifdef SUPPORT_MAILDIR
2902 if (yield == OK && maildirsize_fd >= 0)
2903 maildir_record_length(maildirsize_fd, message_size);
2904 maildir_save_errno = errno; /* Preserve errno while closing the file */
2905 if (maildirsize_fd >= 0)
2906 (void)close(maildirsize_fd);
2907 errno = maildir_save_errno;
2909 #endif /* SUPPORT_MAILDIR */
2911 /* If there is a quota warning threshold and we are have crossed it with this
2912 message, set the SPECIAL_WARN flag in the address, to cause a warning message
2915 if (!disable_quota && THRESHOLD_CHECK)
2917 off_t threshold = ob->quota_warn_threshold_value;
2918 if (ob->quota_warn_threshold_is_percent)
2919 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
2921 debug_printf("quota = " OFF_T_FMT
2922 " threshold = " OFF_T_FMT
2923 " old size = " OFF_T_FMT
2924 " message size = %d\n",
2925 ob->quota_value, threshold, mailbox_size,
2927 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
2928 addr->special_action = SPECIAL_WARN;
2930 /******* You might think that the test ought to be this:
2932 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
2933 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
2935 * (indeed, I was sent a patch with that in). However, it is possible to
2936 * have a warning threshold without actually imposing a quota, and I have
2937 * therefore kept Exim backwards compatible.
2942 /* Handle error while writing the file. Control should come here directly after
2943 the error, with the reason in errno. In the case of expansion failure in prefix
2944 or suffix, it will be ERRNO_EXPANDFAIL. */
2948 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
2950 /* Save the error number. If positive, it will ultimately cause a strerror()
2951 call to generate some text. */
2953 addr->basic_errno = errno;
2955 /* For system or Exim quota excession, or disk full, set more_errno to the
2956 time since the file was last read. If delivery was into a directory, the
2957 time since last read logic is not relevant, in general. However, for maildir
2958 deliveries we can approximate it by looking at the last modified time of the
2959 "new" subdirectory. Since Exim won't be adding new messages, a change to the
2960 "new" subdirectory implies that an MUA has moved a message from there to the
2963 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
2965 addr->more_errno = 0;
2966 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
2968 #ifdef SUPPORT_MAILDIR
2969 else if (mbformat == mbf_maildir)
2971 struct stat statbuf;
2972 if (Ustat("new", &statbuf) < 0)
2974 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
2975 "stat error %d for \"new\": %s\n", errno, strerror(errno));
2977 else /* Want a repeatable time when in test harness */
2978 addr->more_errno = f.running_in_test_harness ? 10 :
2979 (int)time(NULL) - statbuf.st_mtime;
2982 debug_printf("maildir: time since \"new\" directory modified = %s\n",
2983 readconf_printtime(addr->more_errno));
2985 #endif /* SUPPORT_MAILDIR */
2988 /* Handle system quota excession. Add an explanatory phrase for the error
2989 message, since some systems don't have special quota-excession errors,
2990 and on those that do, "quota" doesn't always mean anything to the user. */
2992 if (errno == errno_quota)
2995 addr->message = string_sprintf("mailbox is full "
2996 "(quota exceeded while writing to file %s)", filename);
2998 addr->message = US"mailbox is full";
3000 addr->user_message = US"mailbox is full";
3001 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3003 isdirectory ? US"" : US": time since file read = ",
3004 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3007 /* Handle Exim's own quota-imposition */
3009 else if (errno == ERRNO_EXIMQUOTA)
3011 addr->message = string_sprintf("mailbox is full "
3012 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3014 addr->user_message = US"mailbox is full";
3015 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3016 filecount_msg, dataname,
3017 isdirectory ? US"" : US": time since file read = ",
3018 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3021 /* Handle a process failure while writing via a filter; the return
3022 from child_close() is in more_errno. */
3024 else if (errno == ERRNO_FILTER_FAIL)
3027 addr->message = string_sprintf("transport filter process failed (%d) "
3028 "while writing to %s%s", addr->more_errno, dataname,
3029 (addr->more_errno == EX_EXECFAILED) ? ": unable to execute command" : "");
3032 /* Handle failure to expand header changes */
3034 else if (errno == ERRNO_CHHEADER_FAIL)
3038 string_sprintf("failed to expand headers_add or headers_remove while "
3039 "writing to %s: %s", dataname, expand_string_message);
3042 /* Handle failure to complete writing of a data block */
3044 else if (errno == ERRNO_WRITEINCOMPLETE)
3045 addr->message = string_sprintf("failed to write data block while "
3046 "writing to %s", dataname);
3048 /* Handle length mismatch on MBX copying */
3051 else if (errno == ERRNO_MBXLENGTH)
3052 addr->message = string_sprintf("length mismatch while copying MBX "
3053 "temporary file to %s", dataname);
3054 #endif /* SUPPORT_MBX */
3056 /* For other errors, a general-purpose explanation, if the message is
3059 else if (addr->message == NULL)
3060 addr->message = string_sprintf("error while writing to %s", dataname);
3062 /* For a file, reset the file size to what it was before we started, leaving
3063 the last modification time unchanged, so it will get reset also. All systems
3064 investigated so far have ftruncate(), whereas not all have the F_FREESP
3065 fcntl() call (BSDI & FreeBSD do not). */
3067 if (!isdirectory && ftruncate(fd, saved_size))
3068 DEBUG(D_transport) debug_printf("Error resetting file size\n");
3071 /* Handle successful writing - we want the modification time to be now for
3072 appended files. Remove the default backstop error number. For a directory, now
3073 is the time to rename the file with a unique name. As soon as such a name
3074 appears it may get used by another process, so we close the file first and
3075 check that all is well. */
3079 times.modtime = time(NULL);
3080 addr->basic_errno = 0;
3082 /* Handle the case of writing to a new file in a directory. This applies
3083 to all single-file formats - maildir, mailstore, and "smail format". */
3087 if (fstat(fd, &statbuf) < 0)
3089 addr->basic_errno = errno;
3090 addr->message = string_sprintf("while fstatting opened message file %s",
3095 else if (close(fd) < 0)
3097 addr->basic_errno = errno;
3098 addr->message = string_sprintf("close() error for %s",
3099 (ob->mailstore_format) ? dataname : filename);
3103 /* File is successfully written and closed. Arrange to rename it. For the
3104 different kinds of single-file delivery, some games can be played with the
3105 name. The message size is by this time set to the accurate value so that
3106 its value can be used in expansions. */
3110 uschar *renamename = newname;
3113 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3115 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3116 situation. The name is built by expanding the directory_file option, and
3117 we make the inode number available for use in this. The expansion was
3118 checked for syntactic validity above, before we wrote the file.
3120 We have to be careful here, in case the file name exists. (In the other
3121 cases, the names used are constructed to be unique.) The rename()
3122 function just replaces an existing file - we don't want that! So instead
3123 of calling rename(), we must use link() and unlink().
3125 In this case, if the link fails because of an existing file, we wait
3126 for one second and try the expansion again, to see if it produces a
3127 different value. Do this up to 5 times unless the name stops changing.
3128 This makes it possible to build values that are based on the time, and
3129 still cope with races from multiple simultaneous deliveries. */
3134 uschar *old_renameleaf = US"";
3136 for (int i = 0; ; sleep(1), i++)
3138 deliver_inode = statbuf.st_ino;
3139 renameleaf = expand_string(ob->dirfilename);
3144 addr->transport_return = PANIC;
3145 addr->message = string_sprintf("Expansion of \"%s\" "
3146 "(directory_file for %s transport) failed: %s",
3147 ob->dirfilename, tblock->name, expand_string_message);
3151 renamename = string_sprintf("%s/%s", path, renameleaf);
3152 if (Ulink(filename, renamename) < 0)
3154 DEBUG(D_transport) debug_printf("link failed: %s\n",
3156 if (errno != EEXIST || i >= 4 ||
3157 Ustrcmp(renameleaf, old_renameleaf) == 0)
3159 addr->basic_errno = errno;
3160 addr->message = string_sprintf("while renaming %s as %s",
3161 filename, renamename);
3165 old_renameleaf = renameleaf;
3166 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3175 } /* re-expand loop */
3176 } /* not mailstore or maildir */
3178 /* For maildir and mailstore formats, the new name was created earlier,
3179 except that for maildir, there is the possibility of adding a "tag" on
3180 the end of the name by expanding the value of nametag. This usually
3181 includes a reference to the message size. The expansion of nametag was
3182 checked above, before the file was opened. It either succeeded, or
3183 provoked a soft failure. So any failure here can be treated as soft.
3184 Ignore non-printing characters and / and put a colon at the start if the
3185 first character is alphanumeric. */
3191 uschar *iptr = expand_string(nametag);
3194 uschar *etag = store_get(Ustrlen(iptr) + 2, iptr);
3195 uschar *optr = etag;
3196 for ( ; *iptr; iptr++)
3197 if (mac_isgraph(*iptr) && *iptr != '/')
3199 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3203 renamename = string_sprintf("%s%s", newname, etag);
3207 /* Do the rename. If the name is too long and a tag exists, try again
3210 if (Urename(filename, renamename) < 0 &&
3211 (nametag == NULL || errno != ENAMETOOLONG ||
3212 (renamename = newname, Urename(filename, renamename) < 0)))
3214 addr->basic_errno = errno;
3215 addr->message = string_sprintf("while renaming %s as %s",
3216 filename, renamename);
3220 /* Rename succeeded */
3224 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3226 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3228 } /* maildir or mailstore */
3229 } /* successful write + close */
3231 } /* write success */
3234 /* For a file, restore the last access time (atime), and set the modification
3235 time as required - changed if write succeeded, unchanged if not. */
3237 if (!isdirectory) utime(CS filename, ×);
3239 /* Notify comsat if configured to do so. It only makes sense if the configured
3240 file is the one that the comsat daemon knows about. */
3242 if (ob->notify_comsat && yield == OK && deliver_localpart)
3243 notify_comsat(deliver_localpart, saved_size);
3245 /* Pass back the final return code in the address structure */
3248 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3249 yield, addr->basic_errno, addr->more_errno);
3251 addr->transport_return = yield;
3253 /* Close the file, which will release the fcntl lock. For a directory write it
3254 is closed above, except in cases of error which goto RETURN, when we also need
3255 to remove the original file(s). For MBX locking, if all has gone well, before
3256 closing the file, see if we can get an exclusive lock on it, in which case we
3257 can unlink the /tmp lock file before closing it. This is always a non-blocking
3258 lock; there's no need to wait if we can't get it. If everything has gone right
3259 but close fails, defer the message. Then unlink the lock file, if present. This
3260 point in the code is jumped to from a number of places when errors are
3261 detected, in order to get the file closed and the lock file tidied away. */
3266 if (mbx_lockfd >= 0)
3268 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3269 ob->use_flock, 0) >= 0)
3272 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3273 Uunlink(mbx_lockname);
3275 (void)close(mbx_lockfd);
3277 #endif /* SUPPORT_MBX */
3279 if (fd >= 0 && close(fd) < 0 && yield == OK)
3281 addr->basic_errno = errno;
3282 addr->message = string_sprintf("while closing %s", filename);
3283 addr->transport_return = DEFER;
3286 if (hd >= 0) Uunlink(lockname);
3288 /* We get here with isdirectory and filename set only in error situations. */
3290 if (isdirectory && filename)
3293 if (dataname != filename) Uunlink(dataname);
3296 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3297 file name relies on time + pid. We must not allow the process to finish until
3298 the clock has move on by at least one microsecond. Usually we expect this
3299 already to be the case, but machines keep getting faster... */
3301 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3303 /* A return of FALSE means that if there was an error, a common error was
3304 put in the first address of a batch. */
3309 addr->message = string_sprintf("Tainted '%s' (file or directory "
3310 "name for %s transport) not permitted", path, tblock->name);
3312 addr->transport_return = PANIC;
3316 #endif /*!MACRO_PREDEF*/
3317 /* End of transport/appendfile.c */