1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim maintainers 2020 */
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 = {
117 US"q${base62:$tod_epoch}-$inode", /* dirfilename */
118 NULL, /* message_prefix (default reset in init if not bsmtp) */
119 NULL, /* message_suffix (ditto) */
120 US"anywhere", /* create_file_string (string value for create_file) */
122 NULL, /* quota_directory */
123 NULL, /* quota_filecount */
124 NULL, /* quota_size_regex */
125 NULL, /* quota_warn_threshold */
126 NULL, /* mailbox_size_string */
127 NULL, /* mailbox_filecount_string */
128 NULL, /* expand_maildir_use_size_file */
129 US"^(?:cur|new|\\..*)$", /* maildir_dir_regex */
130 NULL, /* maildir_tag */
131 NULL, /* maildirfolder_create_regex */
132 NULL, /* mailstore_prefix */
133 NULL, /* mailstore_suffix */
134 NULL, /* check_string (default changed for non-bsmtp file)*/
135 NULL, /* escape_string (ditto) */
136 NULL, /* file_format */
138 0, /* quota_warn_threshold_value */
139 -1, /* mailbox_size_value */
140 -1, /* mailbox_filecount_value */
141 0, /* quota_filecount_value */
142 APPENDFILE_MODE, /* mode */
143 APPENDFILE_DIRECTORY_MODE, /* dirmode */
144 APPENDFILE_LOCKFILE_MODE, /* lockfile_mode */
145 30*60, /* lockfile_timeout */
146 0, /* lock_fcntl_timeout */
147 0, /* lock_flock_timeout */
148 10, /* lock_retries */
149 3, /* lock_interval */
150 10, /* maildir_retries */
151 create_anywhere,/* create_file */
153 FALSE, /* allow_fifo */
154 FALSE, /* allow_symlink */
155 FALSE, /* check_group */
156 TRUE, /* check_owner */
157 TRUE, /* create_directory */
158 FALSE, /* notify_comsat */
159 TRUE, /* use_lockfile */
160 FALSE, /* set_use_lockfile */
161 TRUE, /* use_fcntl */
162 FALSE, /* set_use_fcntl */
163 FALSE, /* use_flock */
164 FALSE, /* set_use_flock */
165 FALSE, /* use_mbx_lock */
166 FALSE, /* set_use_mbx_lock */
167 FALSE, /* use_bsmtp */
168 FALSE, /* use_crlf */
169 FALSE, /* file_must_exist */
170 TRUE, /* mode_fail_narrower */
171 FALSE, /* maildir_format */
172 FALSE, /* maildir_use_size_file */
173 FALSE, /* mailstore_format */
174 FALSE, /* mbx_format */
175 FALSE, /* quota_warn_threshold_is_percent */
176 TRUE, /* quota_is_inclusive */
177 FALSE, /* quota_no_check */
178 FALSE /* quota_filecount_no_check */
182 /* Encodings for mailbox formats, and their names. MBX format is actually
183 supported only if SUPPORT_MBX is set. */
185 enum { mbf_unix, mbf_mbx, mbf_smail, mbf_maildir, mbf_mailstore };
187 static const char *mailbox_formats[] = {
188 "unix", "mbx", "smail", "maildir", "mailstore" };
191 /* Check warn threshold only if quota size set or not a percentage threshold
192 percentage check should only be done if quota > 0 */
194 #define THRESHOLD_CHECK (ob->quota_warn_threshold_value > 0 && \
195 (!ob->quota_warn_threshold_is_percent || ob->quota_value > 0))
199 /*************************************************
200 * Setup entry point *
201 *************************************************/
203 /* Called for each delivery in the privileged state, just before the uid/gid
204 are changed and the main entry point is called. We use this function to
205 expand any quota settings, so that it can access files that may not be readable
206 by the user. It is also used to pick up external mailbox size information, if
210 tblock points to the transport instance
211 addrlist addresses about to be delivered (not used)
212 dummy not used (doesn't pass back data)
213 uid the uid that will be set (not used)
214 gid the gid that will be set (not used)
215 errmsg where to put an error message
217 Returns: OK, FAIL, or DEFER
221 appendfile_transport_setup(transport_instance *tblock, address_item *addrlist,
222 transport_feedback *dummy, uid_t uid, gid_t gid, uschar **errmsg)
224 appendfile_transport_options_block *ob =
225 (appendfile_transport_options_block *)(tblock->options_block);
226 uschar *q = ob->quota;
227 double default_value = 0.0;
229 addrlist = addrlist; /* Keep picky compilers happy */
234 if (ob->expand_maildir_use_size_file)
235 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
236 US"`maildir_use_size_file` in transport", tblock->name);
238 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
241 for (int i = 0; i < 5; i++)
245 uschar *which = NULL;
247 if (q == NULL) d = default_value;
251 uschar *s = expand_string(q);
255 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
256 "%s", q, tblock->name, expand_string_message);
257 return f.search_find_defer ? DEFER : FAIL;
260 d = Ustrtod(s, &rest);
262 /* Handle following characters K, M, G, %, the latter being permitted
263 for quota_warn_threshold only. A threshold with no quota setting is
266 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
267 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
268 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
269 else if (*rest == '%' && i == 2)
271 if (ob->quota_value <= 0 && !ob->maildir_use_size_file)
273 else if ((int)d < 0 || (int)d > 100)
275 *errmsg = string_sprintf("Invalid quota_warn_threshold percentage (%d)"
276 " for %s transport", (int)d, tblock->name);
279 ob->quota_warn_threshold_is_percent = TRUE;
284 /* For quota and quota_filecount there may be options
285 appended. Currently only "no_check", so we can be lazy parsing it */
286 if (i < 2 && Ustrstr(rest, "/no_check") == rest)
289 rest += sizeof("/no_check") - 1;
292 Uskip_whitespace(&rest);
296 *errmsg = string_sprintf("Malformed value \"%s\" (expansion of \"%s\") "
297 "in %s transport", s, q, tblock->name);
302 /* Set each value, checking for possible overflow. */
307 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
309 ob->quota_value = (off_t)d;
310 ob->quota_no_check = no_check;
311 q = ob->quota_filecount;
315 if (d >= 2.0*1024.0*1024.0*1024.0)
316 which = US"quota_filecount";
317 ob->quota_filecount_value = (int)d;
318 ob->quota_filecount_no_check = no_check;
319 q = ob->quota_warn_threshold;
323 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
324 which = US"quota_warn_threshold";
325 ob->quota_warn_threshold_value = (off_t)d;
326 q = ob->mailbox_size_string;
327 default_value = -1.0;
331 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
332 which = US"mailbox_size";;
333 ob->mailbox_size_value = (off_t)d;
334 q = ob->mailbox_filecount_string;
338 if (d >= 2.0*1024.0*1024.0*1024.0)
339 which = US"mailbox_filecount";
340 ob->mailbox_filecount_value = (int)d;
346 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
347 "%s transport", which, d, tblock->name);
357 /*************************************************
358 * Initialization entry point *
359 *************************************************/
361 /* Called for each instance, after its options have been read, to
362 enable consistency checks to be done, or anything else that needs
366 appendfile_transport_init(transport_instance *tblock)
368 appendfile_transport_options_block *ob =
369 (appendfile_transport_options_block *)(tblock->options_block);
371 /* Set up the setup entry point, to be called in the privileged state */
373 tblock->setup = appendfile_transport_setup;
375 /* Lock_retries must be greater than zero */
377 if (ob->lock_retries == 0) ob->lock_retries = 1;
379 /* Only one of a file name or directory name must be given. */
381 if (ob->filename && ob->dirname)
382 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
383 "only one of \"file\" or \"directory\" can be specified", tblock->name);
385 /* If a file name was specified, neither quota_filecount nor quota_directory
390 if (ob->quota_filecount)
391 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
392 "quota_filecount must not be set without \"directory\"", tblock->name);
393 if (ob->quota_directory)
394 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
395 "quota_directory must not be set without \"directory\"", tblock->name);
398 /* The default locking depends on whether MBX is set or not. Change the
399 built-in default if none of the lock options has been explicitly set. At least
400 one form of locking is required in all cases, but mbx locking changes the
401 meaning of fcntl and flock locking. */
403 /* Not all operating systems provide flock(). For those that do, if flock is
404 requested, the default for fcntl is FALSE. */
409 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
410 "flock() support was not available in the operating system when this "
411 "binary was built", tblock->name);
412 #endif /* NO_FLOCK */
413 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
418 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
419 !ob->set_use_mbx_lock)
421 ob->use_lockfile = ob->use_flock = FALSE;
422 ob->use_mbx_lock = ob->use_fcntl = TRUE;
424 else if (ob->use_mbx_lock)
426 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
427 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
428 if (!ob->set_use_flock) ob->use_flock = FALSE;
429 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
431 #endif /* SUPPORT_MBX */
433 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
434 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
435 "no locking configured", tblock->name);
437 /* Unset timeouts for non-used locking types */
439 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
440 if (!ob->use_flock) ob->lock_flock_timeout = 0;
442 /* If a directory name was specified, only one of maildir or mailstore may be
443 specified, and if quota_filecount or quota_directory is given, quota must
448 if (ob->maildir_format && ob->mailstore_format)
449 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
450 "only one of maildir and mailstore may be specified", tblock->name);
451 if (ob->quota_filecount != NULL && ob->quota == NULL)
452 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
453 "quota must be set if quota_filecount is set", tblock->name);
454 if (ob->quota_directory != NULL && ob->quota == NULL)
455 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
456 "quota must be set if quota_directory is set", tblock->name);
459 /* If a fixed uid field is set, then a gid field must also be set. */
461 if (tblock->uid_set && !tblock->gid_set && !tblock->expand_gid)
462 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
463 "user set without group for the %s transport", tblock->name);
465 /* If "create_file" is set, check that a valid option is given, and set the
468 if (ob->create_file_string)
471 if (Ustrcmp(ob->create_file_string, "anywhere") == 0)
472 value = create_anywhere;
473 else if (Ustrcmp(ob->create_file_string, "belowhome") == 0)
474 value = create_belowhome;
475 else if (Ustrcmp(ob->create_file_string, "inhome") == 0)
476 value = create_inhome;
478 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
479 "invalid value given for \"file_create\" for the %s transport: %s",
480 tblock->name, ob->create_file_string);
481 ob->create_file = value;
484 /* If quota_warn_threshold is set, set up default for warn_message. It may
485 not be used if the actual threshold for a given delivery ends up as zero,
486 of if it's given as a percentage and there's no quota setting. */
488 if (ob->quota_warn_threshold)
490 if (!tblock->warn_message) tblock->warn_message = US
491 "To: $local_part@$domain\n"
492 "Subject: Your mailbox\n\n"
493 "This message is automatically created by mail delivery software (Exim).\n\n"
494 "The size of your mailbox has exceeded a warning threshold that is\n"
495 "set by the system administrator.\n";
498 /* If batch SMTP is set, force the check and escape strings, and arrange that
499 headers are also escaped. */
503 ob->check_string = US".";
504 ob->escape_string = US"..";
505 ob->options |= topt_escape_headers;
508 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
509 insert default values for for the affixes and the check/escape strings. */
511 else if (!ob->dirname && !ob->maildir_format && !ob->mailstore_format)
513 if (!ob->message_prefix) ob->message_prefix =
514 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
515 if (!ob->message_suffix) ob->message_suffix = US"\n";
516 if (!ob->check_string) ob->check_string = US"From ";
517 if (!ob->escape_string) ob->escape_string = US">From ";
521 /* Set up the bitwise options for transport_write_message from the various
522 driver options. Only one of body_only and headers_only can be set. */
525 (tblock->body_only ? topt_no_headers : 0) |
526 (tblock->headers_only ? topt_no_body : 0) |
527 (tblock->return_path_add ? topt_add_return_path : 0) |
528 (tblock->delivery_date_add ? topt_add_delivery_date : 0) |
529 (tblock->envelope_to_add ? topt_add_envelope_to : 0) |
530 ((ob->use_crlf || ob->mbx_format) ? topt_use_crlf : 0);
535 /*************************************************
537 *************************************************/
539 /* The comsat daemon is the thing that provides asynchronous notification of
540 the arrival of local messages, if requested by the user by "biff y". It is a
541 BSD thing that uses a TCP/IP protocol for communication. A message consisting
542 of the text "user@offset" must be sent, where offset is the place in the
543 mailbox where new mail starts. There is no scope for telling it which file to
544 look at, which makes it a less than useful if mail is being delivered into a
545 non-standard place such as the user's home directory. In fact, it doesn't seem
546 to pay much attention to the offset.
550 offset offset in mailbox
556 notify_comsat(uschar *user, off_t offset)
562 DEBUG(D_transport) debug_printf("notify_comsat called\n");
564 s = string_sprintf("%.200s@" OFF_T_FMT "\n", user, offset);
566 if ((sp = getservbyname("biff", "udp")) == NULL)
568 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
572 host.name = US"localhost";
576 /* This code is all set up to look up "localhost" and use all its addresses
577 until one succeeds. However, it appears that at least on some systems, comsat
578 doesn't listen on the ::1 address. So for the moment, just force the address to
579 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
580 can be changed. (But actually, comsat is probably dying out anyway.) */
583 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
585 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
590 host.address = US"127.0.0.1";
593 for (host_item * h = &host; h; h = h->next)
596 int host_af = Ustrchr(h->address, ':') != NULL ? AF_INET6 : AF_INET;
598 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
600 if ((sock = ip_socket(SOCK_DGRAM, host_af)) < 0) continue;
602 /* Connect never fails for a UDP socket, so don't set a timeout. */
604 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0, NULL);
605 rc = send(sock, s, Ustrlen(s) + 1, 0);
610 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
617 /*************************************************
618 * Check the format of a file *
619 *************************************************/
621 /* This function is called when file_format is set, to check that an existing
622 file has the right format. The format string contains text/transport pairs. The
623 string matching is literal. we just read big_buffer_size bytes, because this is
624 all about the first few bytes of a file.
628 tblock the transport block
629 addr the address block - for inserting error data
631 Returns: pointer to the required transport, or NULL
635 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
637 const uschar *format =
638 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
640 int len = read(cfd, data, sizeof(data));
644 DEBUG(D_transport) debug_printf("checking file format\n");
646 /* An empty file matches the current transport */
648 if (len == 0) return tblock;
650 /* Search the formats for a match */
652 while ((s = string_nextinlist(&format,&sep,big_buffer,big_buffer_size)))
654 int slen = Ustrlen(s);
655 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
656 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
660 for (transport_instance * tt = transports; tt; tt = tt->next)
661 if (Ustrcmp(tp, tt->name) == 0)
664 debug_printf("file format -> %s transport\n", tt->name);
667 addr->basic_errno = ERRNO_BADTRANSPORT;
668 addr->message = string_sprintf("%s transport (for %.*s format) not found",
674 /* Failed to find a match */
676 addr->basic_errno = ERRNO_FORMATUNKNOWN;
677 addr->message = US"mailbox file format unrecognized";
684 /*************************************************
685 * Check directory's files for quota *
686 *************************************************/
688 /* This function is called if quota is set for one of the delivery modes that
689 delivers into a specific directory. It scans the directory and stats all the
690 files in order to get a total size and count. This is an expensive thing to do,
691 but some people are prepared to bear the cost. Alternatively, if size_regex is
692 set, it is used as a regex to try to extract the size from the file name, a
693 strategy that some people use on maildir files on systems where the users have
696 The function is global, because it is also called from tf_maildir.c for maildir
697 folders (which should contain only regular files).
699 Note: Any problems can be written to debugging output, but cannot be written to
700 the log, because we are running as an unprivileged user here.
703 dirname the name of the directory
704 countptr where to add the file count (because this function recurses)
705 regex a compiled regex to get the size from a name
707 Returns: the sum of the sizes of the stattable files
708 zero if the directory cannot be opened
712 check_dir_size(const uschar * dirname, int *countptr, const pcre *regex)
716 int count = *countptr;
718 if (!(dir = exim_opendir(dirname))) return 0;
720 for (struct dirent *ent; ent = readdir(dir); )
722 uschar * path, * name = US ent->d_name;
725 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
729 /* If there's a regex, try to find the size using it */
734 if (pcre_exec(regex, NULL, CS name, Ustrlen(name), 0, 0, ovector,6) >= 2)
737 off_t size = (off_t)Ustrtod(name + ovector[2], &endptr);
738 if (endptr == name + ovector[3])
742 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
748 debug_printf("check_dir_size: regex did not match %s\n", name);
751 /* No regex or no match for the regex, or captured non-digits */
753 path = string_sprintf("%s/%s", dirname, name);
755 if (Ustat(path, &statbuf) < 0)
758 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, path,
762 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
763 sum += statbuf.st_size / statbuf.st_nlink;
764 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
765 sum += check_dir_size(path, &count, regex);
770 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
780 /*************************************************
781 * Apply a lock to a file descriptor *
782 *************************************************/
784 /* This function applies a lock to a file descriptor, using a blocking or
785 non-blocking lock, depending on the timeout value. It can apply either or
786 both of a fcntl() and a flock() lock. However, not all OS support flock();
787 for those that don't, the use_flock option cannot be set.
790 fd the file descriptor
791 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
792 fcntl() format); the flock() type is deduced if needed
793 dofcntl do fcntl() locking
794 fcntltime non-zero to use blocking fcntl()
795 doflock do flock() locking
796 flocktime non-zero to use blocking flock()
798 Returns: yield of the fcntl() or flock() call, with errno preserved;
799 sigalrm_seen set if there has been a timeout
803 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
808 struct flock lock_data;
809 lock_data.l_type = fcntltype;
810 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
812 sigalrm_seen = FALSE;
819 yield = fcntl(fd, F_SETLKW, &lock_data);
824 else yield = fcntl(fd, F_SETLK, &lock_data);
828 if (doflock && (yield >= 0))
830 int flocktype = (fcntltype == F_WRLCK) ? LOCK_EX : LOCK_SH;
834 yield = flock(fd, flocktype);
839 else yield = flock(fd, flocktype | LOCK_NB);
841 #endif /* NO_FLOCK */
850 /*************************************************
851 * Copy message into MBX mailbox *
852 *************************************************/
854 /* This function is called when a message intended for a MBX mailbox has been
855 written to a temporary file. We can now get the size of the message and then
856 copy it in MBX format to the mailbox.
859 to_fd fd to write to (the real mailbox)
860 from_fd fd to read from (the temporary file)
861 saved_size current size of mailbox
863 Returns: OK if all went well, DEFER otherwise, with errno preserved
864 the number of bytes written are added to transport_count
865 by virtue of calling transport_write_block()
868 /* Values taken from c-client */
870 #define MBX_HDRSIZE 2048
871 #define MBX_NUSERFLAGS 30
874 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
879 transport_ctx tctx = { .u={.fd = to_fd}, .options = topt_not_socket };
881 /* If the current mailbox size is zero, write a header block */
886 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
887 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
888 (long int)time(NULL));
889 for (int i = 0; i < MBX_NUSERFLAGS; i++)
890 sprintf (CS(s += Ustrlen(s)), "\015\012");
891 if (!transport_write_block (&tctx, deliver_out_buffer, MBX_HDRSIZE, FALSE))
895 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
897 /* Now construct the message's header from the time and the RFC822 file
898 size, including CRLFs, which is the size of the input (temporary) file. */
900 if (fstat(from_fd, &statbuf) < 0) return DEFER;
901 size = statbuf.st_size;
903 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
904 tod_stamp(tod_mbx), size, 0L, 0, 0);
905 used = Ustrlen(deliver_out_buffer);
907 /* Rewind the temporary file, and copy it over in chunks. */
909 if (lseek(from_fd, 0 , SEEK_SET) < 0) return DEFER;
913 int len = read(from_fd, deliver_out_buffer + used,
914 DELIVER_OUT_BUFFER_SIZE - used);
917 if (len == 0) errno = ERRNO_MBXLENGTH;
920 if (!transport_write_block(&tctx, deliver_out_buffer, used + len, FALSE))
928 #endif /* SUPPORT_MBX */
932 /*************************************************
933 * Check creation is permitted *
934 *************************************************/
936 /* This function checks whether a given file name is permitted to be created,
937 as controlled by the create_file option. If no home directory is set, however,
938 we can't do any tests.
941 filename the file name
942 create_file the ob->create_file option
944 Returns: TRUE if creation is permitted
948 check_creation(uschar *filename, int create_file)
952 if (deliver_home && create_file != create_anywhere)
954 int len = Ustrlen(deliver_home);
955 uschar *file = filename;
957 while (file[0] == '/' && file[1] == '/') file++;
958 if (Ustrncmp(file, deliver_home, len) != 0 || file[len] != '/' ||
959 ( Ustrchr(file+len+2, '/') != NULL &&
961 create_file != create_belowhome ||
962 Ustrstr(file+len, "/../") != NULL
967 /* If yield is TRUE, the file name starts with the home directory, and does
968 not contain any instances of "/../" in the "belowhome" case. However, it may
969 still contain symbolic links. We can check for this by making use of
970 realpath(), which most Unixes seem to have (but make it possible to cut this
971 out). We can't just use realpath() on the whole file name, because we know
972 the file itself doesn't exist, and intermediate directories may also not
973 exist. What we want to know is the real path of the longest existing part of
974 the path. That must match the home directory's beginning, whichever is the
978 if (yield && create_file == create_belowhome)
982 for (uschar * slash = Ustrrchr(file, '/'); /* There is known to be one */
983 !rp && slash > file; /* Stop if reached beginning */
987 rp = US realpath(CS file, CS big_buffer);
988 next = Ustrrchr(file, '/');
992 /* If rp == NULL it means that none of the relevant directories exist.
993 This is not a problem here - it means that no symbolic links can exist,
994 which is all we are worried about. Otherwise, we must compare it
995 against the start of the home directory. However, that may itself
996 contain symbolic links, so we have to "realpath" it as well, if
1001 uschar hdbuffer[PATH_MAX+1];
1002 uschar *rph = deliver_home;
1003 int rlen = Ustrlen(big_buffer);
1005 if ((rp = US realpath(CS deliver_home, CS hdbuffer)))
1011 if (rlen > len) rlen = len;
1012 if (Ustrncmp(rph, big_buffer, rlen) != 0)
1015 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
1016 big_buffer, deliver_home);
1020 #endif /* NO_REALPATH */
1028 /*************************************************
1029 * Main entry point *
1030 *************************************************/
1032 /* See local README for general interface details. This transport always
1033 returns FALSE, indicating that the status which has been placed in the first
1034 address should be copied to any other addresses in a batch.
1036 Appendfile delivery is tricky and has led to various security problems in other
1037 mailers. The logic used here is therefore laid out in some detail. When this
1038 function is called, we are running in a subprocess which has had its gid and
1039 uid set to the appropriate values. Therefore, we cannot write directly to the
1040 exim logs. Any errors must be handled by setting appropriate return codes.
1041 Note that the default setting for addr->transport_return is DEFER, so it need
1042 not be set unless some other value is required.
1044 The code below calls geteuid() rather than getuid() to get the current uid
1045 because in weird configurations not running setuid root there may be a
1046 difference. In the standard configuration, where setuid() has been used in the
1047 delivery process, there will be no difference between the uid and the euid.
1049 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1050 alias expansion. Otherwise, there must be a configured file name or
1053 The following items apply in the case when a file name (as opposed to a
1054 directory name) is given, that is, when appending to a single file:
1056 (2f) Expand the file name.
1058 (3f) If the file name is /dev/null, return success (optimization).
1060 (4f) If the file_format options is set, open the file for reading, and check
1061 that the bytes at the start of the file match one of the given strings.
1062 If the check indicates a transport other than the current one should be
1063 used, pass control to that other transport. Otherwise continue. An empty
1064 or non-existent file matches the current transport. The file is closed
1067 (5f) If a lock file is required, create it (see extensive separate comments
1068 below about the algorithm for doing this). It is important to do this
1069 before opening the mailbox if NFS is in use.
1071 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1072 details of any symbolic link.
1074 (7f) If the file already exists:
1076 Check the owner and group if necessary, and defer if they are wrong.
1078 If it is a symbolic link AND the allow_symlink option is set (NOT the
1079 default), go back to (6f) but this time use stat() instead of lstat().
1081 If it's not a regular file (or FIFO when permitted), defer delivery.
1083 Check permissions. If the required permissions are *less* than the
1084 existing ones, or supplied by the address (often by the user via filter),
1085 chmod() the file. Otherwise, defer.
1087 Save the inode number.
1089 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1091 If open fails because the file does not exist, go to (6f); on any other
1094 Check the inode number hasn't changed - I realize this isn't perfect (an
1095 inode can be reused) but it's cheap and will catch some of the races.
1097 Check it's still a regular file (or FIFO if permitted).
1099 Check that the owner and permissions haven't changed.
1101 If file_format is set, check that the file still matches the format for
1102 the current transport. If not, defer delivery.
1104 (8f) If file does not exist initially:
1106 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1107 this is via a symbolic link (only possible if allow_symlinks is set), in
1108 which case don't use O_EXCL, as it doesn't work.
1110 If open fails because the file already exists, go to (6f). To avoid
1111 looping for ever in a situation where the file is continuously being
1112 created and deleted, all of this happens inside a loop that operates
1113 lock_retries times and includes the fcntl and flock locking. If the
1114 loop completes without the file getting opened, defer and request
1115 freezing, because something really weird is happening.
1117 If open fails for any other reason, defer for subsequent delivery except
1118 when this is a file delivery resulting from an alias or forward expansion
1119 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1120 most likely a user rather than a configuration error.
1122 (9f) We now have the file checked and open for writing. If so configured, lock
1123 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1124 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1125 still fails, give up and defer delivery.
1127 (10f)Save the access time (for subsequent restoration) and the size of the
1128 file, for comsat and for re-setting if delivery fails in the middle -
1129 e.g. for quota exceeded.
1131 The following items apply in the case when a directory name is given:
1133 (2d) Create a new file in the directory using a temporary name, by opening for
1134 writing and with O_CREAT. If maildir format is being used, the file
1135 is created in a temporary subdirectory with a prescribed name. If
1136 mailstore format is being used, the envelope file is first created with a
1137 temporary name, then the data file.
1139 The following items apply in all cases:
1141 (11) We now have the file open for writing, and locked if it was given as a
1142 file name. Write the message and flush the file, unless there is a setting
1143 of the local quota option, in which case we can check for its excession
1144 without doing any writing.
1146 In the case of MBX format mailboxes, the message is first written to a
1147 temporary file, in order to get its correct length. This is then copied to
1148 the real file, preceded by an MBX header.
1150 If there is a quota error on writing, defer the address. Timeout logic
1151 will determine for how long retries are attempted. We restore the mailbox
1152 to its original length if it's a single file. There doesn't seem to be a
1153 uniform error code for quota excession (it even differs between SunOS4
1154 and some versions of SunOS5) so a system-dependent macro called
1155 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1158 For any other error (most commonly disk full), do the same.
1160 The following applies after appending to a file:
1162 (12f)Restore the atime; notify_comsat if required; close the file (which
1163 unlocks it if it was locked). Delete the lock file if it exists.
1165 The following applies after writing a unique file in a directory:
1167 (12d)For maildir format, rename the file into the new directory. For mailstore
1168 format, rename the envelope file to its correct name. Otherwise, generate
1169 a unique name from the directory_file option, and rename to that, possibly
1170 trying a few times if the file exists and re-expanding the name gives a
1173 This transport yields FAIL only when a file name is generated by an alias or
1174 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1175 All other failures return DEFER (in addr->transport_return). */
1179 appendfile_transport_entry(
1180 transport_instance *tblock, /* data for this instantiation */
1181 address_item *addr) /* address we are working on */
1183 appendfile_transport_options_block *ob =
1184 (appendfile_transport_options_block *)(tblock->options_block);
1185 struct stat statbuf;
1186 uschar *fdname = NULL;
1187 uschar *filename = NULL;
1188 uschar *hitchname = NULL;
1189 uschar *dataname = NULL;
1190 uschar *lockname = NULL;
1191 uschar *newname = NULL;
1192 uschar *nametag = NULL;
1194 uschar *filecount_msg = US"";
1196 struct utimbuf times;
1197 struct timeval msg_tv;
1198 BOOL disable_quota = FALSE;
1199 BOOL isdirectory = FALSE;
1200 BOOL isfifo = FALSE;
1201 BOOL wait_for_tick = FALSE;
1202 uid_t uid = geteuid(); /* See note above */
1203 gid_t gid = getegid();
1205 int mode = (addr->mode > 0) ? addr->mode : ob->mode;
1206 off_t saved_size = -1;
1207 off_t mailbox_size = ob->mailbox_size_value;
1208 int mailbox_filecount = ob->mailbox_filecount_value;
1216 int mbx_lockfd = -1;
1217 uschar mbx_lockname[40];
1218 FILE *temp_file = NULL;
1219 #endif /* SUPPORT_MBX */
1221 #ifdef SUPPORT_MAILDIR
1222 int maildirsize_fd = -1; /* fd for maildirsize file */
1223 int maildir_save_errno;
1227 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1229 /* An "address_file" or "address_directory" transport is used to deliver to
1230 files specified via .forward or an alias file. Prior to release 4.20, the
1231 "file" and "directory" options were ignored in this case. This has been changed
1232 to allow the redirection data to specify what is in effect a folder, whose
1233 location is determined by the options on the transport.
1235 Compatibility with the case when neither option is set is retained by forcing a
1236 value for the file or directory name. A directory delivery is assumed if the
1237 last character of the path from the router is '/'.
1239 The file path is in the local part of the address, but not in the $local_part
1240 variable (that holds the parent local part). It is, however, in the
1241 $address_file variable. Below, we update the local part in the address if it
1242 changes by expansion, so that the final path ends up in the log. */
1244 if (testflag(addr, af_file) && !ob->filename && !ob->dirname)
1246 fdname = US"$address_file";
1247 if (address_file[Ustrlen(address_file)-1] == '/' ||
1248 ob->maildir_format ||
1249 ob->mailstore_format)
1253 /* Handle (a) an "address file" delivery where "file" or "directory" is
1254 explicitly set and (b) a non-address_file delivery, where one of "file" or
1255 "directory" must be set; initialization ensures that they are not both set. */
1259 if (!(fdname = ob->filename))
1261 fdname = ob->dirname;
1266 addr->message = string_sprintf("Mandatory file or directory option "
1267 "missing from %s transport", tblock->name);
1272 /* Maildir and mailstore require a directory */
1274 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1276 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1277 "to be specified for the %s transport",
1278 ob->maildir_format ? "dir" : "store", tblock->name);
1282 if (!(path = expand_string(fdname)))
1284 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1285 "name for %s transport) failed: %s", fdname, tblock->name,
1286 expand_string_message);
1290 if (m = is_tainted2(path, 0, "Tainted '%s' (file or directory "
1291 "name for %s transport) not permitted", path, tblock->name))
1300 addr->message = string_sprintf("appendfile: file or directory name "
1301 "\"%s\" is not absolute", path);
1302 addr->basic_errno = ERRNO_NOTABSOLUTE;
1306 /* For a file delivery, make sure the local part in the address(es) is updated
1307 to the true local part. */
1309 if (testflag(addr, af_file))
1310 for (address_item * addr2 = addr; addr2; addr2 = addr2->next)
1311 addr2->local_part = string_copy(path);
1313 /* The available mailbox formats depend on whether it is a directory or a file
1319 #ifdef SUPPORT_MAILDIR
1320 ob->maildir_format ? mbf_maildir :
1322 #ifdef SUPPORT_MAILSTORE
1323 ob->mailstore_format ? mbf_mailstore :
1331 ob->mbx_format ? mbf_mbx :
1338 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1340 " warning=" OFF_T_FMT "%s\n"
1341 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1342 "maildir_use_size_file=%s\n",
1343 mode, ob->notify_comsat, ob->quota_value,
1344 ob->quota_no_check ? " (no_check)" : "",
1345 ob->quota_filecount_no_check ? " (no_check_filecount)" : "",
1346 ob->quota_warn_threshold_value,
1347 ob->quota_warn_threshold_is_percent ? "%" : "",
1348 isdirectory ? "directory" : "file",
1349 path, mailbox_formats[mbformat],
1350 !ob->message_prefix ? US"null" : string_printing(ob->message_prefix),
1351 !ob->message_suffix ? US"null" : string_printing(ob->message_suffix),
1352 ob->maildir_use_size_file ? "yes" : "no");
1354 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1355 ob->use_lockfile ? "lockfile " : "",
1356 ob->use_mbx_lock ? "mbx locking (" : "",
1357 ob->use_fcntl ? "fcntl " : "",
1358 ob->use_flock ? "flock" : "",
1359 ob->use_mbx_lock ? ")" : "");
1362 /* If the -N option is set, can't do any more. */
1367 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1369 addr->transport_return = OK;
1373 /* Handle the case of a file name. If the file name is /dev/null, we can save
1374 ourselves some effort and just give a success return right away. */
1378 BOOL use_lstat = TRUE;
1379 BOOL file_opened = FALSE;
1380 BOOL allow_creation_here = TRUE;
1382 if (Ustrcmp(path, "/dev/null") == 0)
1384 addr->transport_return = OK;
1388 /* Set the name of the file to be opened, and the file to which the data
1389 is written, and find out if we are permitted to create a non-existent file. */
1391 dataname = filename = path;
1392 allow_creation_here = check_creation(filename, ob->create_file);
1394 /* If ob->create_directory is set, attempt to create the directories in
1395 which this mailbox lives, but only if we are permitted to create the file
1396 itself. We know we are dealing with an absolute path, because this was
1399 if (ob->create_directory && allow_creation_here)
1401 uschar *p = Ustrrchr(path, '/');
1403 if (!directory_make(NULL, path, ob->dirmode, FALSE))
1405 addr->basic_errno = errno;
1407 string_sprintf("failed to create directories for %s: %s", path,
1409 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1415 /* If file_format is set we must check that any existing file matches one of
1416 the configured formats by checking the bytes it starts with. A match then
1417 indicates a specific transport - if it is not this one, pass control to it.
1418 Otherwise carry on here. An empty or non-existent file matches the current
1419 transport. We don't need to distinguish between non-existence and other open
1420 failures because if an existing file fails to open here, it will also fail
1421 again later when O_RDWR is used. */
1423 if (ob->file_format)
1425 int cfd = Uopen(path, O_RDONLY, 0);
1428 transport_instance *tt = check_file_format(cfd, tblock, addr);
1431 /* If another transport is indicated, call it and return; if no transport
1432 was found, just return - the error data will have been set up.*/
1438 set_process_info("delivering %s to %s using %s", message_id,
1439 addr->local_part, tt->name);
1440 debug_print_string(tt->debug_string);
1441 addr->transport = tt;
1442 (tt->info->code)(tt, addr);
1449 /* The locking of mailbox files is worse than the naming of cats, which is
1450 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1451 three different names, so several different styles of locking are used.
1453 Research in other programs that lock mailboxes shows that there is no
1454 universally standard method. Having mailboxes NFS-mounted on the system that
1455 is delivering mail is not the best thing, but people do run like this,
1456 and so the code must do its best to cope.
1458 Three different locking mechanisms are supported. The initialization function
1459 checks that at least one is configured.
1463 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1464 will work over NFS. Only after that is done do we actually open the mailbox
1465 and apply locks to it (if configured).
1467 Originally, Exim got the file opened before doing anything about locking.
1468 However, a very occasional problem was observed on Solaris 2 when delivering
1469 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1470 gets remembered at open time. If another process on another host (that's
1471 important) has the file open and locked and writes to it and then releases
1472 the lock while the first process is waiting to get the lock, the first
1473 process may fail to write at the new end point of the file - despite the very
1474 definite statement about O_APPEND in the man page for write(). Experiments
1475 have reproduced this problem, but I do not know any way of forcing a host to
1476 update its attribute cache for an open NFS file. It would be nice if it did
1477 so when a lock was taken out, but this does not seem to happen. Anyway, to
1478 reduce the risk of this problem happening, we now create the lock file
1479 (if configured) *before* opening the mailbox. That will prevent two different
1480 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1481 however, but Pine at least seems to operate in the same way.
1483 Lockfiles should normally be used when NFS is involved, because of the above
1486 The logic for creating the lock file is:
1488 . The name of the lock file is <mailbox-name>.lock
1490 . First, create a "hitching post" name by adding the primary host name,
1491 current time and pid to the lock file name. This should be unique.
1493 . Create the hitching post file using WRONLY + CREAT + EXCL.
1495 . If that fails EACCES, we assume it means that the user is unable to create
1496 files in the mail spool directory. Some installations might operate in this
1497 manner, so there is a configuration option to allow this state not to be an
1498 error - we proceed to lock using fcntl only, after the file is open.
1500 . Otherwise, an error causes a deferment of the address.
1502 . Hard link the hitching post to the lock file name.
1504 . If the link succeeds, we have successfully created the lock file. Simply
1505 close and unlink the hitching post file.
1507 . If the link does not succeed, proceed as follows:
1509 o Fstat the hitching post file, and then close and unlink it.
1511 o Now examine the stat data. If the number of links to the file is exactly
1512 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1513 the return never made it back, so the link() function gave a failure
1516 . This method allows for the lock file to be created by some other process
1517 right up to the moment of the attempt to hard link it, and is also robust
1518 against NFS server crash-reboots, which would probably result in timeouts
1519 in the middle of link().
1521 . System crashes may cause lock files to get left lying around, and some means
1522 of flushing them is required. The approach of writing a pid (used by smail
1523 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1524 timeout, which seems a better approach. Since any program that writes to a
1525 mailbox using a lock file should complete its task very quickly, Pine
1526 removes lock files that are older than 5 minutes. We allow the value to be
1527 configurable on the transport.
1531 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1532 mailbox once it is open. This is done by default with a non-blocking lock.
1533 Failures to lock cause retries after a sleep, but only for a certain number
1534 of tries. A blocking lock is deliberately not used so that we don't hold the
1535 mailbox open. This minimizes the possibility of the NFS problem described
1536 under LOCK FILES above, if for some reason NFS deliveries are happening
1537 without lock files. However, the use of a non-blocking lock and sleep, though
1538 the safest approach, does not give the best performance on very busy systems.
1539 A blocking lock plus timeout does better. Therefore Exim has an option to
1540 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1541 enables the use of blocking fcntl() calls.
1545 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1546 same manner as for fcntl locking above. No-blocking/timeout is also set as
1547 above in lock_flock_timeout. Not all operating systems provide or support
1548 flock(). For those that don't (as determined by the definition of LOCK_SH in
1549 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1550 is implemented (not precisely) on top of fcntl(), which means there's no
1551 point in actually using it.
1555 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1556 then the rules used for locking in c-client are used. Exim takes out a shared
1557 lock on the mailbox file, and an exclusive lock on the file whose name is
1558 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1559 any other MBX client from getting an exclusive lock on it and expunging it.
1560 It also stops any other MBX client from unlinking the /tmp lock when it has
1563 The exclusive lock on the /tmp file prevents any other MBX client from
1564 updating the mailbox in any way. When writing is finished, if an exclusive
1565 lock on the mailbox can be obtained, indicating there are no current sharers,
1566 the /tmp file is unlinked.
1568 MBX locking can use either fcntl() or flock() locking. If neither
1569 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1570 The calls for getting these locks are by default non-blocking, as for non-mbx
1571 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1572 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1573 probably makes sense to set timeouts for any MBX deliveries. */
1576 /* Build a lock file if configured to do so - the existence of a lock
1577 file is subsequently checked by looking for a non-negative value of the
1578 file descriptor hd - even though the file is no longer open. */
1580 if (ob->use_lockfile)
1582 /* cf. exim_lock.c */
1583 lockname = string_sprintf("%s.lock", filename);
1584 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1585 (unsigned int)(time(NULL)), (unsigned int)getpid());
1587 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1590 /* Lock file creation retry loop */
1592 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1596 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1599 addr->basic_errno = errno;
1601 string_sprintf("creating lock file hitching post %s "
1602 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1603 (long int)getegid());
1607 /* Attempt to hitch the hitching post to the lock file. If link()
1608 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1609 file, and get rid of the hitching post. If the number of links was 2,
1610 the link was created, despite the failure of link(). If the hitch was
1611 not successful, try again, having unlinked the lock file if it is too
1614 There's a version of Linux (2.0.27) which doesn't update its local cache
1615 of the inode after link() by default - which many think is a bug - but
1616 if the link succeeds, this code will be OK. It just won't work in the
1617 case when link() fails after having actually created the link. The Linux
1618 NFS person is fixing this; a temporary patch is available if anyone is
1619 sufficiently worried. */
1621 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1624 if (rc != 0 && statbuf.st_nlink != 2)
1626 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1627 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1629 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1632 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1636 DEBUG(D_transport) debug_printf("lock file created\n");
1640 /* Check for too many tries at creating the lock file */
1642 if (i >= ob->lock_retries)
1644 addr->basic_errno = ERRNO_LOCKFAILED;
1645 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1652 /* We now have to get the file open. First, stat() it and act on existence or
1653 non-existence. This is in a loop to handle the case of a file's being created
1654 or deleted as we watch, and also to handle retries when the locking fails.
1655 Rather than holding the file open while waiting for the fcntl() and/or
1656 flock() lock, we close and do the whole thing again. This should be safer,
1657 especially for NFS files, which might get altered from other hosts, making
1658 their cached sizes incorrect.
1660 With the default settings, no symlinks are permitted, but there is an option
1661 to permit symlinks for those sysadmins that know what they are doing.
1662 Shudder. However, insist that the initial symlink is owned by the right user.
1663 Thus lstat() is used initially; if a symlink is discovered, the loop is
1664 repeated such that stat() is used, to look at the end file. */
1666 for (i = 0; i < ob->lock_retries; i++)
1668 int sleep_before_retry = TRUE;
1669 file_opened = FALSE;
1671 if ((use_lstat ? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1673 /* Let's hope that failure to stat (other than non-existence) is a
1676 if (errno != ENOENT)
1678 addr->basic_errno = errno;
1679 addr->message = string_sprintf("attempting to stat mailbox %s",
1684 /* File does not exist. If it is required to pre-exist this state is an
1687 if (ob->file_must_exist)
1689 addr->basic_errno = errno;
1690 addr->message = string_sprintf("mailbox %s does not exist, "
1691 "but file_must_exist is set", filename);
1695 /* If not permitted to create this file because it isn't in or below
1696 the home directory, generate an error. */
1698 if (!allow_creation_here)
1700 addr->basic_errno = ERRNO_BADCREATE;
1701 addr->message = string_sprintf("mailbox %s does not exist, "
1702 "but creation outside the home directory is not permitted",
1707 /* Attempt to create and open the file. If open fails because of
1708 pre-existence, go round the loop again. For any other error, defer the
1709 address, except for an alias or forward generated file name with EPERM,
1710 ENOENT, or EACCES, as those are most likely to be user errors rather
1711 than Exim config errors. When a symbolic link is permitted and points
1712 to a non-existent file, we get here with use_lstat = FALSE. In this case
1713 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1714 consistency and because MBX locking requires it in order to be able to
1715 get a shared lock. */
1717 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1718 (use_lstat ? O_EXCL : 0), mode);
1721 if (errno == EEXIST) continue;
1722 addr->basic_errno = errno;
1723 addr->message = string_sprintf("while creating mailbox %s",
1725 if (testflag(addr, af_file) &&
1726 (errno == EPERM || errno == ENOENT || errno == EACCES))
1727 addr->transport_return = FAIL;
1731 /* We have successfully created and opened the file. Ensure that the group
1732 and the mode are correct. */
1734 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
1736 addr->basic_errno = errno;
1737 addr->message = string_sprintf("while setting perms on mailbox %s",
1739 addr->transport_return = FAIL;
1745 /* The file already exists. Test its type, ownership, and permissions, and
1746 save the inode for checking later. If symlinks are permitted (not the
1747 default or recommended state) it may be a symlink that already exists.
1748 Check its ownership and then look for the file at the end of the link(s).
1749 This at least prevents one user creating a symlink for another user in
1750 a sticky directory. */
1754 int oldmode = (int)statbuf.st_mode;
1755 ino_t inode = statbuf.st_ino;
1756 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1758 isfifo = FALSE; /* In case things are changing */
1760 /* Check owner if required - the default. */
1762 if (ob->check_owner && statbuf.st_uid != uid)
1764 addr->basic_errno = ERRNO_BADUGID;
1765 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1766 "(%ld != %ld)", filename,
1767 islink ? " (symlink)" : "",
1768 (long int)(statbuf.st_uid), (long int)uid);
1772 /* Group is checked only if check_group is set. */
1774 if (ob->check_group && statbuf.st_gid != gid)
1776 addr->basic_errno = ERRNO_BADUGID;
1777 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1778 filename, islink ? " (symlink)" : "", statbuf.st_gid, gid);
1782 /* Just in case this is a sticky-bit mail directory, we don't want
1783 users to be able to create hard links to other users' files. */
1785 if (statbuf.st_nlink != 1)
1787 addr->basic_errno = ERRNO_NOTREGULAR;
1788 addr->message = string_sprintf("mailbox %s%s has too many links (%lu)",
1789 filename, islink ? " (symlink)" : "", (unsigned long)statbuf.st_nlink);
1794 /* If symlinks are permitted (not recommended), the lstat() above will
1795 have found the symlink. Its ownership has just been checked; go round
1796 the loop again, using stat() instead of lstat(). That will never yield a
1799 if (islink && ob->allow_symlink)
1802 i--; /* Don't count this time round */
1806 /* An actual file exists. Check that it is a regular file, or FIFO
1809 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1811 else if ((oldmode & S_IFMT) != S_IFREG)
1813 addr->basic_errno = ERRNO_NOTREGULAR;
1814 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1815 filename, ob->allow_fifo ? " or named pipe" : "");
1819 /* If the mode is not what it would be for a newly created file, change
1820 the permissions if the mode is supplied for the address. Otherwise,
1821 reduce but do not extend the permissions. If the newly created
1822 permissions are greater than the existing permissions, don't change
1823 things when the mode is not from the address. */
1825 if ((oldmode &= 07777) != mode)
1827 int diffs = oldmode ^ mode;
1828 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1830 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1831 if (Uchmod(filename, mode) < 0)
1833 addr->basic_errno = errno;
1834 addr->message = string_sprintf("attempting to chmod mailbox %s",
1841 /* Mode not from address, and newly-created permissions are greater
1842 than existing permissions. Default is to complain, but it can be
1843 configured to go ahead and try to deliver anyway if that's what
1844 the administration wants. */
1846 else if (ob->mode_fail_narrower)
1848 addr->basic_errno = ERRNO_BADMODE;
1849 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1850 "(%o expected)", filename, oldmode, mode);
1855 /* We are happy with the existing file. Open it, and then do further
1856 tests to ensure that it is the same file that we were just looking at.
1857 If the file does not now exist, restart this loop, going back to using
1858 lstat again. For an NFS error, just defer; other opening errors are
1859 more serious. The file is opened RDWR so that its format can be checked,
1860 and also MBX locking requires the use of a shared (read) lock. However,
1861 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1862 reading the pipe. */
1864 fd = Uopen(filename, isfifo ? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1868 if (errno == ENOENT)
1873 addr->basic_errno = errno;
1875 addr->message = string_sprintf("while opening named pipe %s "
1876 "(could mean no process is reading it)", filename);
1877 else if (errno != EWOULDBLOCK)
1878 addr->message = string_sprintf("while opening mailbox %s", filename);
1882 /* This fstat really shouldn't fail, as we have an open file! There's a
1883 dilemma here. We use fstat in order to be sure we are peering at the file
1884 we have got open. However, that won't tell us if the file was reached
1885 via a symbolic link. We checked this above, but there is a race exposure
1886 if the link was created between the previous lstat and the open. However,
1887 it would have to be created with the same inode in order to pass the
1888 check below. If ob->allow_symlink is set, causing the use of stat rather
1889 than lstat above, symbolic links may be there anyway, and the checking is
1892 if (fstat(fd, &statbuf) < 0)
1894 addr->basic_errno = errno;
1895 addr->message = string_sprintf("attempting to stat open mailbox %s",
1900 /* Check the inode; this is isn't a perfect check, but gives some
1903 if (inode != statbuf.st_ino)
1905 addr->basic_errno = ERRNO_INODECHANGED;
1906 addr->message = string_sprintf("opened mailbox %s inode number changed "
1907 "from " INO_T_FMT " to " INO_T_FMT, filename, inode, statbuf.st_ino);
1908 addr->special_action = SPECIAL_FREEZE;
1912 /* Check it's still a regular file or FIFO, and the uid, gid, and
1913 permissions have not changed. */
1915 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1916 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1918 addr->basic_errno = ERRNO_NOTREGULAR;
1920 string_sprintf("opened mailbox %s is no longer a %s", filename,
1921 isfifo ? "named pipe" : "regular file");
1922 addr->special_action = SPECIAL_FREEZE;
1926 if ((ob->check_owner && statbuf.st_uid != uid) ||
1927 (ob->check_group && statbuf.st_gid != gid))
1929 addr->basic_errno = ERRNO_BADUGID;
1931 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
1932 addr->special_action = SPECIAL_FREEZE;
1936 if ((statbuf.st_mode & 07777) != oldmode)
1938 addr->basic_errno = ERRNO_BADMODE;
1939 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
1940 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
1941 addr->special_action = SPECIAL_FREEZE;
1945 /* If file_format is set, check that the format of the file has not
1946 changed. Error data is set by the testing function. */
1948 if (ob->file_format && check_file_format(fd, tblock, addr) != tblock)
1950 addr->message = US"open mailbox has changed format";
1954 /* The file is OK. Carry on to do the locking. */
1957 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
1958 locking rules if configured to do so. If a lock file is also required, it
1959 was created above and hd was left >= 0. At least one form of locking is
1960 required by the initialization function. If locking fails here, close the
1961 file and go round the loop all over again, after waiting for a bit, unless
1962 blocking locking was used. */
1965 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
1966 sleep_before_retry = FALSE;
1968 /* Simple fcntl() and/or flock() locking */
1970 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
1972 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1973 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
1976 /* MBX locking rules */
1979 else if (ob->use_mbx_lock)
1982 struct stat lstatbuf, statbuf2;
1983 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1984 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
1985 fstat(fd, &statbuf) >= 0)
1987 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
1988 (long)statbuf.st_ino);
1991 * 2010-05-29: SECURITY
1992 * Dan Rosenberg reported the presence of a race-condition in the
1993 * original code here. Beware that many systems still allow symlinks
1994 * to be followed in /tmp so an attacker can create a symlink pointing
1995 * elsewhere between a stat and an open, which we should avoid
1998 * It's unfortunate that we can't just use all the heavily debugged
1999 * locking from above.
2001 * Also: remember to mirror changes into exim_lock.c */
2003 /* first leave the old pre-check in place, it provides better
2004 * diagnostics for common cases */
2005 if (Ulstat(mbx_lockname, &statbuf) >= 0)
2007 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
2009 addr->basic_errno = ERRNO_LOCKFAILED;
2010 addr->message = string_sprintf("symbolic link on MBX lock file %s",
2014 if (statbuf.st_nlink > 1)
2016 addr->basic_errno = ERRNO_LOCKFAILED;
2017 addr->message = string_sprintf("hard link to MBX lock file %s",
2023 /* If we could just declare "we must be the ones who create this
2024 * file" then a hitching post in a subdir would work, since a
2025 * subdir directly in /tmp/ which we create wouldn't follow links
2026 * but this isn't our locking logic, so we can't safely change the
2027 * file existence rules. */
2029 /* On systems which support O_NOFOLLOW, it's the easiest and most
2030 * obviously correct security fix */
2031 mbx_tmp_oflags = O_RDWR | O_CREAT;
2033 mbx_tmp_oflags |= O_NOFOLLOW;
2035 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
2038 addr->basic_errno = ERRNO_LOCKFAILED;
2039 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2040 mbx_lockname, strerror(errno));
2044 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2046 addr->basic_errno = ERRNO_LOCKFAILED;
2047 addr->message = string_sprintf("attempting to lstat open MBX "
2048 "lock file %s: %s", mbx_lockname, strerror(errno));
2051 if (fstat(mbx_lockfd, &statbuf2) < 0)
2053 addr->basic_errno = ERRNO_LOCKFAILED;
2054 addr->message = string_sprintf("attempting to stat fd of open MBX "
2055 "lock file %s: %s", mbx_lockname, strerror(errno));
2061 * statbuf: if exists, is file which existed prior to opening the
2062 * lockfile, might have been replaced since then
2063 * statbuf2: result of stat'ing the open fd, is what was actually
2065 * lstatbuf: result of lstat'ing the filename immediately after
2066 * the open but there's a race condition again between
2067 * those two steps: before open, symlink to foo, after
2068 * open but before lstat have one of:
2069 * * was no symlink, so is the opened file
2070 * (we created it, no messing possible after that point)
2072 * * symlink elsewhere
2073 * * hardlink elsewhere
2075 * Don't want to compare to device of /tmp because some modern systems
2076 * have regressed to having /tmp be the safe actual filesystem as
2077 * valuable data, so is mostly worthless, unless we assume that *only*
2078 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2079 * for further consideration.
2080 * No point in doing a readlink on the lockfile as that will always be
2081 * at a different point in time from when we open it, so tells us
2082 * nothing; attempts to clean up and delete after ourselves would risk
2083 * deleting a *third* filename.
2085 if ((statbuf2.st_nlink > 1) ||
2086 (lstatbuf.st_nlink > 1) ||
2087 (!S_ISREG(lstatbuf.st_mode)) ||
2088 (lstatbuf.st_dev != statbuf2.st_dev) ||
2089 (lstatbuf.st_ino != statbuf2.st_ino))
2091 addr->basic_errno = ERRNO_LOCKFAILED;
2092 addr->message = string_sprintf("RACE CONDITION detected: "
2093 "mismatch post-initial-checks between \"%s\" and opened "
2094 "fd lead us to abort!", mbx_lockname);
2098 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2100 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2101 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2103 struct stat ostatbuf;
2105 /* This tests for a specific race condition. Ensure that we still
2106 have the same file. */
2108 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2109 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2110 statbuf.st_dev == ostatbuf.st_dev &&
2111 statbuf.st_ino == ostatbuf.st_ino)
2113 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2114 "between creation and locking\n", mbx_lockname);
2117 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2119 (void)close(mbx_lockfd);
2124 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2125 filename, strerror(errno));
2128 #endif /* SUPPORT_MBX */
2130 else break; /* No on-file locking required; break the open/lock loop */
2133 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2137 use_lstat = TRUE; /* Reset to use lstat first */
2140 /* If a blocking call timed out, break the retry loop if the total time
2141 so far is not less than than retries * interval. Use the larger of the
2142 flock() and fcntl() timeouts. */
2145 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2146 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2147 ob->lock_retries * ob->lock_interval)
2148 i = ob->lock_retries;
2150 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2151 flock() that caused the problem. */
2153 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2156 /* Test for exceeding the maximum number of tries. Either the file remains
2157 locked, or, if we haven't got it open, something is terribly wrong... */
2159 if (i >= ob->lock_retries)
2163 addr->basic_errno = ERRNO_EXISTRACE;
2164 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2165 addr->special_action = SPECIAL_FREEZE;
2169 addr->basic_errno = ERRNO_LOCKFAILED;
2170 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2176 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2178 /* Save access time (for subsequent restoration), modification time (for
2179 restoration if updating fails), size of file (for comsat and for re-setting if
2180 delivery fails in the middle - e.g. for quota exceeded). */
2182 if (fstat(fd, &statbuf) < 0)
2184 addr->basic_errno = errno;
2185 addr->message = string_sprintf("while fstatting opened mailbox %s",
2190 times.actime = statbuf.st_atime;
2191 times.modtime = statbuf.st_mtime;
2192 saved_size = statbuf.st_size;
2193 if (mailbox_size < 0) mailbox_size = saved_size;
2194 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2197 /* Prepare for writing to a new file (as opposed to appending to an old one).
2198 There are several different formats, but there is preliminary stuff concerned
2199 with quotas that applies to all of them. Finding the current size by directory
2200 scanning is expensive; for maildirs some fudges have been invented:
2202 (1) A regex can be used to extract a file size from its name;
2203 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2209 uschar *check_path = path; /* Default quota check path */
2210 const pcre *regex = NULL; /* Regex for file size from file name */
2212 if (!check_creation(string_sprintf("%s/any", path), ob->create_file))
2214 addr->basic_errno = ERRNO_BADCREATE;
2215 addr->message = string_sprintf("tried to create file in %s, but "
2216 "file creation outside the home directory is not permitted", path);
2220 #ifdef SUPPORT_MAILDIR
2221 /* For a maildir delivery, ensure that all the relevant directories exist,
2222 and a maildirfolder file if necessary. */
2224 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2225 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2227 #endif /* SUPPORT_MAILDIR */
2229 /* If we are going to do a quota check, of if maildir_use_size_file is set
2230 for a maildir delivery, compile the regular expression if there is one. We
2231 may also need to adjust the path that is used. We need to do this for
2232 maildir_use_size_file even if the quota is unset, because we still want to
2233 create the file. When maildir support is not compiled,
2234 ob->maildir_use_size_file is always FALSE. */
2236 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2238 const uschar *error;
2241 /* Compile the regex if there is one. */
2243 if (ob->quota_size_regex)
2245 if (!(regex = pcre_compile(CS ob->quota_size_regex, PCRE_COPT,
2246 CCSS &error, &offset, NULL)))
2248 addr->message = string_sprintf("appendfile: regular expression "
2249 "error: %s at offset %d while compiling %s", error, offset,
2250 ob->quota_size_regex);
2253 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2254 ob->quota_size_regex);
2257 /* Use an explicitly configured directory if set */
2259 if (ob->quota_directory)
2261 if (!(check_path = expand_string(ob->quota_directory)))
2263 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2264 "name for %s transport) failed: %s", ob->quota_directory,
2265 tblock->name, expand_string_message);
2269 if (check_path[0] != '/')
2271 addr->message = string_sprintf("appendfile: quota_directory name "
2272 "\"%s\" is not absolute", check_path);
2273 addr->basic_errno = ERRNO_NOTABSOLUTE;
2278 #ifdef SUPPORT_MAILDIR
2279 /* Otherwise, if we are handling a maildir delivery, and the directory
2280 contains a file called maildirfolder, this is a maildir++ feature telling
2281 us that this is a sub-directory of the real inbox. We should therefore do
2282 the quota check on the parent directory. Beware of the special case when
2283 the directory name itself ends in a slash. */
2285 else if (mbformat == mbf_maildir)
2287 struct stat statbuf;
2288 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2290 uschar *new_check_path = string_copy(check_path);
2291 uschar *slash = Ustrrchr(new_check_path, '/');
2297 slash = Ustrrchr(new_check_path, '/');
2302 check_path = new_check_path;
2303 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2304 "quota check directory changed to %s\n", check_path);
2309 #endif /* SUPPORT_MAILDIR */
2312 /* If we are using maildirsize files, we need to ensure that such a file
2313 exists and, if necessary, recalculate its contents. As a byproduct of this,
2314 we obtain the current size of the maildir. If no quota is to be enforced
2315 (ob->quota_value == 0), we still need the size if a threshold check will
2318 Another regular expression is used to determine which directories inside the
2319 maildir are going to be counted. */
2321 #ifdef SUPPORT_MAILDIR
2322 if (ob->maildir_use_size_file)
2324 const pcre *dir_regex = NULL;
2325 const uschar *error;
2328 if (ob->maildir_dir_regex)
2330 int check_path_len = Ustrlen(check_path);
2332 if (!(dir_regex = pcre_compile(CS ob->maildir_dir_regex, PCRE_COPT,
2333 CCSS &error, &offset, NULL)))
2335 addr->message = string_sprintf("appendfile: regular expression "
2336 "error: %s at offset %d while compiling %s", error, offset,
2337 ob->maildir_dir_regex);
2342 debug_printf("using regex for maildir directory selection: %s\n",
2343 ob->maildir_dir_regex);
2345 /* Check to see if we are delivering into an ignored directory, that is,
2346 if the delivery path starts with the quota check path, and the rest
2347 of the deliver path matches the regex; if so, set a flag to disable quota
2348 checking and maildirsize updating. */
2350 if (Ustrncmp(path, check_path, check_path_len) == 0)
2352 uschar *s = path + check_path_len;
2353 while (*s == '/') s++;
2354 s = (*s == 0) ? US "new" : string_sprintf("%s/new", s);
2355 if (pcre_exec(dir_regex, NULL, CS s, Ustrlen(s), 0, 0, NULL, 0) < 0)
2357 disable_quota = TRUE;
2358 DEBUG(D_transport) debug_printf("delivery directory does not match "
2359 "maildir_quota_directory_regex: disabling quota\n");
2364 /* Quota enforcement; create and check the file. There is some discussion
2365 about whether this should happen if the quota is unset. At present, Exim
2366 always creates the file. If we ever want to change this, uncomment
2367 appropriate lines below, possibly doing a check on some option. */
2369 /* if (???? || ob->quota_value > 0) */
2376 if ((maildirsize_fd = maildir_ensure_sizefile(check_path, ob, regex, dir_regex,
2377 &size, &filecount)) == -1)
2379 addr->basic_errno = errno;
2380 addr->message = string_sprintf("while opening or reading "
2381 "%s/maildirsize", check_path);
2384 /* can also return -2, which means that the file was removed because of
2385 raciness; but in this case, the size & filecount will still have been
2388 if (mailbox_size < 0) mailbox_size = size;
2389 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2392 /* No quota enforcement; ensure file does *not* exist; calculate size if
2397 * time_t old_latest;
2398 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2399 * if (THRESHOLD_CHECK)
2400 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2401 * regex, dir_regex, FALSE);
2406 #endif /* SUPPORT_MAILDIR */
2408 /* Otherwise if we are going to do a quota check later on, and the mailbox
2409 size is not set, find the current size of the mailbox. Ditto for the file
2410 count. Note that ob->quota_filecount_value cannot be set without
2411 ob->quota_value being set. */
2413 if (!disable_quota &&
2414 (ob->quota_value > 0 || THRESHOLD_CHECK) &&
2415 (mailbox_size < 0 ||
2416 (mailbox_filecount < 0 && ob->quota_filecount_value > 0)))
2421 debug_printf("quota checks on directory %s\n", check_path);
2422 size = check_dir_size(check_path, &filecount, regex);
2423 if (mailbox_size < 0) mailbox_size = size;
2424 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2427 /* Handle the case of creating a unique file in a given directory (not in
2428 maildir or mailstore format - this is how smail did it). A temporary name is
2429 used to create the file. Later, when it is written, the name is changed to a
2430 unique one. There is no need to lock the file. An attempt is made to create
2431 the directory if it does not exist. */
2433 if (mbformat == mbf_smail)
2436 debug_printf("delivering to new file in %s\n", path);
2437 filename = dataname =
2438 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2439 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2440 if (fd < 0 && /* failed to open, and */
2441 (errno != ENOENT || /* either not non-exist */
2442 !ob->create_directory || /* or not allowed to make */
2443 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2444 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2446 addr->basic_errno = errno;
2447 addr->message = string_sprintf("while creating file %s", filename);
2452 #ifdef SUPPORT_MAILDIR
2454 /* Handle the case of a unique file in maildir format. The file is written to
2455 the tmp subdirectory, with a prescribed form of name. */
2457 else if (mbformat == mbf_maildir)
2460 debug_printf("delivering in maildir format in %s\n", path);
2462 nametag = ob->maildir_tag;
2464 /* Check that nametag expands successfully; a hard failure causes a panic
2465 return. The actual expansion for use happens again later, when
2466 $message_size is accurately known. */
2468 if (nametag && !expand_string(nametag) && !f.expand_string_forcedfail)
2470 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2471 "for %s transport) failed: %s", nametag, tblock->name,
2472 expand_string_message);
2476 /* We ensured the existence of all the relevant directories above. Attempt
2477 to open the temporary file a limited number of times. I think this rather
2478 scary-looking for statement is actually OK. If open succeeds, the loop is
2479 broken; if not, there is a test on the value of i. Get the time again
2480 afresh each time round the loop. Its value goes into a variable that is
2481 checked at the end, to make sure we don't release this process until the
2482 clock has ticked. */
2484 for (int i = 1;; i++)
2488 (void)gettimeofday(&msg_tv, NULL);
2489 basename = string_sprintf(TIME_T_FMT ".H%luP" PID_T_FMT ".%s",
2490 msg_tv.tv_sec, msg_tv.tv_usec, getpid(), primary_hostname);
2492 filename = dataname = string_sprintf("tmp/%s", basename);
2493 newname = string_sprintf("new/%s", basename);
2495 if (Ustat(filename, &statbuf) == 0)
2497 else if (errno == ENOENT)
2499 if ((fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode)) >= 0)
2501 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2502 filename, strerror(errno));
2505 /* Too many retries - give up */
2507 if (i >= ob->maildir_retries)
2509 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2510 filename, i, (i == 1) ? "y" : "ies");
2511 addr->basic_errno = errno;
2512 if (errno == errno_quota || errno == ENOSPC)
2513 addr->user_message = US"mailbox is full";
2517 /* Open or stat failed but we haven't tried too many times yet. */
2522 /* Note that we have to ensure the clock has ticked before leaving */
2524 wait_for_tick = TRUE;
2526 /* Why are these here? Put in because they are present in the non-maildir
2527 directory case above. */
2529 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2531 addr->basic_errno = errno;
2532 addr->message = string_sprintf("while setting perms on maildir %s",
2538 #endif /* SUPPORT_MAILDIR */
2540 #ifdef SUPPORT_MAILSTORE
2542 /* Handle the case of a unique file in mailstore format. First write the
2543 envelope to a temporary file, then open the main file. The unique base name
2544 for the files consists of the message id plus the pid of this delivery
2550 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2551 string_base62((long int)getpid()));
2554 debug_printf("delivering in mailstore format in %s\n", path);
2556 filename = string_sprintf("%s.tmp", mailstore_basename);
2557 newname = string_sprintf("%s.env", mailstore_basename);
2558 dataname = string_sprintf("%s.msg", mailstore_basename);
2560 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2561 if (fd < 0 && /* failed to open, and */
2562 (errno != ENOENT || /* either not non-exist */
2563 !ob->create_directory || /* or not allowed to make */
2564 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2565 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2567 addr->basic_errno = errno;
2568 addr->message = string_sprintf("while creating file %s", filename);
2572 /* Why are these here? Put in because they are present in the non-maildir
2573 directory case above. */
2575 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2577 addr->basic_errno = errno;
2578 addr->message = string_sprintf("while setting perms on file %s",
2583 /* Built a C stream from the open file descriptor. */
2585 if (!(env_file = fdopen(fd, "wb")))
2587 addr->basic_errno = errno;
2588 addr->message = string_sprintf("fdopen of %s ("
2589 "for %s transport) failed", filename, tblock->name);
2595 /* Write the envelope file, then close it. */
2597 if (ob->mailstore_prefix)
2599 uschar *s = expand_string(ob->mailstore_prefix);
2602 if (!f.expand_string_forcedfail)
2604 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2605 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2606 tblock->name, expand_string_message);
2607 (void)fclose(env_file);
2615 fprintf(env_file, "%s", CS s);
2616 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2620 fprintf(env_file, "%s\n", sender_address);
2622 for (address_item * taddr = addr; taddr; taddr = taddr->next)
2623 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2625 if (ob->mailstore_suffix)
2627 uschar *s = expand_string(ob->mailstore_suffix);
2630 if (!f.expand_string_forcedfail)
2632 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2633 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2634 tblock->name, expand_string_message);
2635 (void)fclose(env_file);
2643 fprintf(env_file, "%s", CS s);
2644 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2648 if (fclose(env_file) != 0)
2650 addr->basic_errno = errno;
2651 addr->message = string_sprintf("while closing %s", filename);
2656 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2658 /* Now open the data file, and ensure that it has the correct ownership and
2661 if ((fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)
2663 addr->basic_errno = errno;
2664 addr->message = string_sprintf("while creating file %s", dataname);
2668 if (exim_chown(dataname, uid, gid) || Uchmod(dataname, mode))
2670 addr->basic_errno = errno;
2671 addr->message = string_sprintf("while setting perms on file %s",
2677 #endif /* SUPPORT_MAILSTORE */
2680 /* In all cases of writing to a new file, ensure that the file which is
2681 going to be renamed has the correct ownership and mode. */
2683 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2685 addr->basic_errno = errno;
2686 addr->message = string_sprintf("while setting perms on file %s",
2693 /* At last we can write the message to the file, preceded by any configured
2694 prefix line, and followed by any configured suffix line. If there are any
2695 writing errors, we must defer. */
2697 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2702 /* If there is a local quota setting, check that we are not going to exceed it
2703 with this message if quota_is_inclusive is set; if it is not set, the check
2704 is for the mailbox already being over quota (i.e. the current message is not
2705 included in the check). */
2707 if (!disable_quota && ob->quota_value > 0)
2711 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2712 " this message = %d (%sincluded)\n",
2713 ob->quota_value, mailbox_size, message_size,
2714 ob->quota_is_inclusive ? "" : "not ");
2715 debug_printf(" file count quota = %d count = %d\n",
2716 ob->quota_filecount_value, mailbox_filecount);
2719 if (mailbox_size + (ob->quota_is_inclusive ? message_size:0) > ob->quota_value)
2720 if (!ob->quota_no_check)
2722 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2724 errno = ERRNO_EXIMQUOTA;
2727 DEBUG(D_transport) debug_printf("mailbox quota exceeded but ignored\n");
2729 if (ob->quota_filecount_value > 0
2730 && mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2731 ob->quota_filecount_value)
2732 if (!ob->quota_filecount_no_check)
2734 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2736 errno = ERRNO_EXIMQUOTA;
2737 filecount_msg = US" filecount";
2739 else DEBUG(D_transport) if (ob->quota_filecount_no_check)
2740 debug_printf("mailbox file count quota exceeded but ignored\n");
2744 /* If we are writing in MBX format, what we actually do is to write the message
2745 to a temporary file, and then copy it to the real file once we know its size.
2746 This is the most straightforward way of getting the correct length in the
2747 separator line. So, what we do here is to save the real file descriptor, and
2748 replace it with one for a temporary file. The temporary file gets unlinked once
2749 opened, so that it goes away on closure. */
2752 if (yield == OK && ob->mbx_format)
2754 if (!(temp_file = tmpfile()))
2756 addr->basic_errno = errno;
2757 addr->message = US"while setting up temporary file";
2762 fd = fileno(temp_file);
2763 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2765 #endif /* SUPPORT_MBX */
2767 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2770 transport_count = 0;
2771 transport_newlines = 0;
2773 /* Write any configured prefix text first */
2775 if (yield == OK && ob->message_prefix && *ob->message_prefix)
2777 uschar *prefix = expand_string(ob->message_prefix);
2780 errno = ERRNO_EXPANDFAIL;
2781 addr->transport_return = PANIC;
2782 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2783 "transport) failed", ob->message_prefix, tblock->name);
2786 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2789 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2790 various different values for batching are handled outside; if there is more
2791 than one address available here, all must be included. If any address is a
2792 file, use its parent in the RCPT TO. */
2794 if (yield == OK && ob->use_bsmtp)
2796 transport_count = 0;
2797 transport_newlines = 0;
2798 if (ob->use_crlf) cr = US"\r";
2799 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2803 transport_newlines++;
2804 for (address_item * a = addr; a; a = a->next)
2806 address_item * b = testflag(a, af_pfr) ? a->parent : a;
2807 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2808 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2809 { yield = DEFER; break; }
2810 transport_newlines++;
2812 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2815 transport_newlines++;
2819 /* Now the message itself. The options for transport_write_message were set up
2820 at initialization time. */
2824 transport_ctx tctx = {
2828 .check_string = ob->check_string,
2829 .escape_string = ob->escape_string,
2830 .options = ob->options | topt_not_socket
2832 if (!transport_write_message(&tctx, 0))
2836 /* Now a configured suffix. */
2838 if (yield == OK && ob->message_suffix && *ob->message_suffix)
2840 uschar *suffix = expand_string(ob->message_suffix);
2843 errno = ERRNO_EXPANDFAIL;
2844 addr->transport_return = PANIC;
2845 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2846 "transport) failed", ob->message_suffix, tblock->name);
2849 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2852 /* If batch smtp, write the terminating dot. */
2854 if (yield == OK && ob->use_bsmtp)
2855 if (!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2856 else transport_newlines++;
2858 /* If MBX format is being used, all that writing was to the temporary file.
2859 However, if there was an earlier failure (Exim quota exceeded, for example),
2860 the temporary file won't have got opened - and no writing will have been done.
2861 If writing was OK, we restore the fd, and call a function that copies the
2862 message in MBX format into the real file. Otherwise use the temporary name in
2866 if (temp_file && ob->mbx_format)
2873 transport_count = 0; /* Reset transport count for actual write */
2874 /* No need to reset transport_newlines as we're just using a block copy
2875 * routine so the number won't be affected */
2876 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2878 else if (errno >= 0) dataname = US"temporary file";
2880 /* Preserve errno while closing the temporary file. */
2882 mbx_save_errno = errno;
2883 (void)fclose(temp_file);
2884 errno = mbx_save_errno;
2886 #endif /* SUPPORT_MBX */
2888 /* Force out the remaining data to check for any errors; some OS don't allow
2889 fsync() to be called for a FIFO. */
2891 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2893 /* Update message_size and message_linecount to the accurate count of bytes
2894 written, including added headers. Note; we subtract 1 from message_linecount as
2895 this variable doesn't count the new line between the header and the body of the
2898 message_size = transport_count;
2899 message_linecount = transport_newlines - 1;
2901 /* If using a maildir++ quota file, add this message's size to it, and
2902 close the file descriptor, except when the quota has been disabled because we
2903 are delivering into an uncounted folder. */
2905 #ifdef SUPPORT_MAILDIR
2908 if (yield == OK && maildirsize_fd >= 0)
2909 maildir_record_length(maildirsize_fd, message_size);
2910 maildir_save_errno = errno; /* Preserve errno while closing the file */
2911 if (maildirsize_fd >= 0)
2912 (void)close(maildirsize_fd);
2913 errno = maildir_save_errno;
2915 #endif /* SUPPORT_MAILDIR */
2917 /* If there is a quota warning threshold and we are have crossed it with this
2918 message, set the SPECIAL_WARN flag in the address, to cause a warning message
2921 if (!disable_quota && THRESHOLD_CHECK)
2923 off_t threshold = ob->quota_warn_threshold_value;
2924 if (ob->quota_warn_threshold_is_percent)
2925 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
2927 debug_printf("quota = " OFF_T_FMT
2928 " threshold = " OFF_T_FMT
2929 " old size = " OFF_T_FMT
2930 " message size = %d\n",
2931 ob->quota_value, threshold, mailbox_size,
2933 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
2934 addr->special_action = SPECIAL_WARN;
2936 /******* You might think that the test ought to be this:
2938 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
2939 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
2941 * (indeed, I was sent a patch with that in). However, it is possible to
2942 * have a warning threshold without actually imposing a quota, and I have
2943 * therefore kept Exim backwards compatible.
2948 /* Handle error while writing the file. Control should come here directly after
2949 the error, with the reason in errno. In the case of expansion failure in prefix
2950 or suffix, it will be ERRNO_EXPANDFAIL. */
2954 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
2956 /* Save the error number. If positive, it will ultimately cause a strerror()
2957 call to generate some text. */
2959 addr->basic_errno = errno;
2961 /* For system or Exim quota excession, or disk full, set more_errno to the
2962 time since the file was last read. If delivery was into a directory, the
2963 time since last read logic is not relevant, in general. However, for maildir
2964 deliveries we can approximate it by looking at the last modified time of the
2965 "new" subdirectory. Since Exim won't be adding new messages, a change to the
2966 "new" subdirectory implies that an MUA has moved a message from there to the
2969 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
2971 addr->more_errno = 0;
2972 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
2974 #ifdef SUPPORT_MAILDIR
2975 else if (mbformat == mbf_maildir)
2977 struct stat statbuf;
2978 if (Ustat("new", &statbuf) < 0)
2980 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
2981 "stat error %d for \"new\": %s\n", errno, strerror(errno));
2983 else /* Want a repeatable time when in test harness */
2984 addr->more_errno = f.running_in_test_harness ? 10 :
2985 (int)time(NULL) - statbuf.st_mtime;
2988 debug_printf("maildir: time since \"new\" directory modified = %s\n",
2989 readconf_printtime(addr->more_errno));
2991 #endif /* SUPPORT_MAILDIR */
2994 /* Handle system quota excession. Add an explanatory phrase for the error
2995 message, since some systems don't have special quota-excession errors,
2996 and on those that do, "quota" doesn't always mean anything to the user. */
2998 if (errno == errno_quota)
3001 addr->message = string_sprintf("mailbox is full "
3002 "(quota exceeded while writing to file %s)", filename);
3004 addr->message = US"mailbox is full";
3006 addr->user_message = US"mailbox is full";
3007 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3009 isdirectory ? US"" : US": time since file read = ",
3010 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3013 /* Handle Exim's own quota-imposition */
3015 else if (errno == ERRNO_EXIMQUOTA)
3017 addr->message = string_sprintf("mailbox is full "
3018 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3020 addr->user_message = US"mailbox is full";
3021 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3022 filecount_msg, dataname,
3023 isdirectory ? US"" : US": time since file read = ",
3024 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3027 /* Handle a process failure while writing via a filter; the return
3028 from child_close() is in more_errno. */
3030 else if (errno == ERRNO_FILTER_FAIL)
3033 addr->message = string_sprintf("transport filter process failed (%d) "
3034 "while writing to %s%s", addr->more_errno, dataname,
3035 (addr->more_errno == EX_EXECFAILED) ? ": unable to execute command" : "");
3038 /* Handle failure to expand header changes */
3040 else if (errno == ERRNO_CHHEADER_FAIL)
3044 string_sprintf("failed to expand headers_add or headers_remove while "
3045 "writing to %s: %s", dataname, expand_string_message);
3048 /* Handle failure to complete writing of a data block */
3050 else if (errno == ERRNO_WRITEINCOMPLETE)
3051 addr->message = string_sprintf("failed to write data block while "
3052 "writing to %s", dataname);
3054 /* Handle length mismatch on MBX copying */
3057 else if (errno == ERRNO_MBXLENGTH)
3058 addr->message = string_sprintf("length mismatch while copying MBX "
3059 "temporary file to %s", dataname);
3060 #endif /* SUPPORT_MBX */
3062 /* For other errors, a general-purpose explanation, if the message is
3065 else if (addr->message == NULL)
3066 addr->message = string_sprintf("error while writing to %s", dataname);
3068 /* For a file, reset the file size to what it was before we started, leaving
3069 the last modification time unchanged, so it will get reset also. All systems
3070 investigated so far have ftruncate(), whereas not all have the F_FREESP
3071 fcntl() call (BSDI & FreeBSD do not). */
3073 if (!isdirectory && ftruncate(fd, saved_size))
3074 DEBUG(D_transport) debug_printf("Error resetting file size\n");
3077 /* Handle successful writing - we want the modification time to be now for
3078 appended files. Remove the default backstop error number. For a directory, now
3079 is the time to rename the file with a unique name. As soon as such a name
3080 appears it may get used by another process, so we close the file first and
3081 check that all is well. */
3085 times.modtime = time(NULL);
3086 addr->basic_errno = 0;
3088 /* Handle the case of writing to a new file in a directory. This applies
3089 to all single-file formats - maildir, mailstore, and "smail format". */
3093 if (fstat(fd, &statbuf) < 0)
3095 addr->basic_errno = errno;
3096 addr->message = string_sprintf("while fstatting opened message file %s",
3101 else if (close(fd) < 0)
3103 addr->basic_errno = errno;
3104 addr->message = string_sprintf("close() error for %s",
3105 (ob->mailstore_format) ? dataname : filename);
3109 /* File is successfully written and closed. Arrange to rename it. For the
3110 different kinds of single-file delivery, some games can be played with the
3111 name. The message size is by this time set to the accurate value so that
3112 its value can be used in expansions. */
3116 uschar *renamename = newname;
3119 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3121 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3122 situation. The name is built by expanding the directory_file option, and
3123 we make the inode number available for use in this. The expansion was
3124 checked for syntactic validity above, before we wrote the file.
3126 We have to be careful here, in case the file name exists. (In the other
3127 cases, the names used are constructed to be unique.) The rename()
3128 function just replaces an existing file - we don't want that! So instead
3129 of calling rename(), we must use link() and unlink().
3131 In this case, if the link fails because of an existing file, we wait
3132 for one second and try the expansion again, to see if it produces a
3133 different value. Do this up to 5 times unless the name stops changing.
3134 This makes it possible to build values that are based on the time, and
3135 still cope with races from multiple simultaneous deliveries. */
3140 uschar *old_renameleaf = US"";
3142 for (int i = 0; ; sleep(1), i++)
3144 deliver_inode = statbuf.st_ino;
3145 renameleaf = expand_string(ob->dirfilename);
3150 addr->transport_return = PANIC;
3151 addr->message = string_sprintf("Expansion of \"%s\" "
3152 "(directory_file for %s transport) failed: %s",
3153 ob->dirfilename, tblock->name, expand_string_message);
3157 renamename = string_sprintf("%s/%s", path, renameleaf);
3158 if (Ulink(filename, renamename) < 0)
3160 DEBUG(D_transport) debug_printf("link failed: %s\n",
3162 if (errno != EEXIST || i >= 4 ||
3163 Ustrcmp(renameleaf, old_renameleaf) == 0)
3165 addr->basic_errno = errno;
3166 addr->message = string_sprintf("while renaming %s as %s",
3167 filename, renamename);
3171 old_renameleaf = renameleaf;
3172 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3181 } /* re-expand loop */
3182 } /* not mailstore or maildir */
3184 /* For maildir and mailstore formats, the new name was created earlier,
3185 except that for maildir, there is the possibility of adding a "tag" on
3186 the end of the name by expanding the value of nametag. This usually
3187 includes a reference to the message size. The expansion of nametag was
3188 checked above, before the file was opened. It either succeeded, or
3189 provoked a soft failure. So any failure here can be treated as soft.
3190 Ignore non-printing characters and / and put a colon at the start if the
3191 first character is alphanumeric. */
3197 uschar *iptr = expand_string(nametag);
3200 uschar *etag = store_get(Ustrlen(iptr) + 2, is_tainted(iptr));
3201 uschar *optr = etag;
3202 for ( ; *iptr; iptr++)
3203 if (mac_isgraph(*iptr) && *iptr != '/')
3205 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3209 renamename = string_sprintf("%s%s", newname, etag);
3213 /* Do the rename. If the name is too long and a tag exists, try again
3216 if (Urename(filename, renamename) < 0 &&
3217 (nametag == NULL || errno != ENAMETOOLONG ||
3218 (renamename = newname, Urename(filename, renamename) < 0)))
3220 addr->basic_errno = errno;
3221 addr->message = string_sprintf("while renaming %s as %s",
3222 filename, renamename);
3226 /* Rename succeeded */
3230 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3232 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3234 } /* maildir or mailstore */
3235 } /* successful write + close */
3237 } /* write success */
3240 /* For a file, restore the last access time (atime), and set the modification
3241 time as required - changed if write succeeded, unchanged if not. */
3243 if (!isdirectory) utime(CS filename, ×);
3245 /* Notify comsat if configured to do so. It only makes sense if the configured
3246 file is the one that the comsat daemon knows about. */
3248 if (ob->notify_comsat && yield == OK && deliver_localpart)
3249 notify_comsat(deliver_localpart, saved_size);
3251 /* Pass back the final return code in the address structure */
3254 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3255 yield, addr->basic_errno, addr->more_errno);
3257 addr->transport_return = yield;
3259 /* Close the file, which will release the fcntl lock. For a directory write it
3260 is closed above, except in cases of error which goto RETURN, when we also need
3261 to remove the original file(s). For MBX locking, if all has gone well, before
3262 closing the file, see if we can get an exclusive lock on it, in which case we
3263 can unlink the /tmp lock file before closing it. This is always a non-blocking
3264 lock; there's no need to wait if we can't get it. If everything has gone right
3265 but close fails, defer the message. Then unlink the lock file, if present. This
3266 point in the code is jumped to from a number of places when errors are
3267 detected, in order to get the file closed and the lock file tidied away. */
3272 if (mbx_lockfd >= 0)
3274 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3275 ob->use_flock, 0) >= 0)
3278 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3279 Uunlink(mbx_lockname);
3281 (void)close(mbx_lockfd);
3283 #endif /* SUPPORT_MBX */
3285 if (fd >= 0 && close(fd) < 0 && yield == OK)
3287 addr->basic_errno = errno;
3288 addr->message = string_sprintf("while closing %s", filename);
3289 addr->transport_return = DEFER;
3292 if (hd >= 0) Uunlink(lockname);
3294 /* We get here with isdirectory and filename set only in error situations. */
3296 if (isdirectory && filename)
3299 if (dataname != filename) Uunlink(dataname);
3302 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3303 file name relies on time + pid. We must not allow the process to finish until
3304 the clock has move on by at least one microsecond. Usually we expect this
3305 already to be the case, but machines keep getting faster... */
3307 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3309 /* A return of FALSE means that if there was an error, a common error was
3310 put in the first address of a batch. */
3315 addr->transport_return = PANIC;
3319 #endif /*!MACRO_PREDEF*/
3320 /* End of transport/appendfile.c */