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 if (ob->expand_maildir_use_size_file)
230 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
231 US"`maildir_use_size_file` in transport", tblock->name);
233 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
236 for (int i = 0; i < 5; i++)
240 uschar *which = NULL;
242 if (q == NULL) d = default_value;
246 uschar *s = expand_string(q);
250 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
251 "%s", q, tblock->name, expand_string_message);
252 return f.search_find_defer ? DEFER : FAIL;
255 d = Ustrtod(s, &rest);
257 /* Handle following characters K, M, G, %, the latter being permitted
258 for quota_warn_threshold only. A threshold with no quota setting is
261 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
262 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
263 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
264 else if (*rest == '%' && i == 2)
266 if (ob->quota_value <= 0 && !ob->maildir_use_size_file)
268 else if ((int)d < 0 || (int)d > 100)
270 *errmsg = string_sprintf("Invalid quota_warn_threshold percentage (%d)"
271 " for %s transport", (int)d, tblock->name);
274 ob->quota_warn_threshold_is_percent = TRUE;
279 /* For quota and quota_filecount there may be options
280 appended. Currently only "no_check", so we can be lazy parsing it */
281 if (i < 2 && Ustrstr(rest, "/no_check") == rest)
284 rest += sizeof("/no_check") - 1;
287 Uskip_whitespace(&rest);
291 *errmsg = string_sprintf("Malformed value \"%s\" (expansion of \"%s\") "
292 "in %s transport", s, q, tblock->name);
297 /* Set each value, checking for possible overflow. */
302 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
304 ob->quota_value = (off_t)d;
305 ob->quota_no_check = no_check;
306 q = ob->quota_filecount;
310 if (d >= 2.0*1024.0*1024.0*1024.0)
311 which = US"quota_filecount";
312 ob->quota_filecount_value = (int)d;
313 ob->quota_filecount_no_check = no_check;
314 q = ob->quota_warn_threshold;
318 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
319 which = US"quota_warn_threshold";
320 ob->quota_warn_threshold_value = (off_t)d;
321 q = ob->mailbox_size_string;
322 default_value = -1.0;
326 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
327 which = US"mailbox_size";;
328 ob->mailbox_size_value = (off_t)d;
329 q = ob->mailbox_filecount_string;
333 if (d >= 2.0*1024.0*1024.0*1024.0)
334 which = US"mailbox_filecount";
335 ob->mailbox_filecount_value = (int)d;
341 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
342 "%s transport", which, d, tblock->name);
352 /*************************************************
353 * Initialization entry point *
354 *************************************************/
356 /* Called for each instance, after its options have been read, to
357 enable consistency checks to be done, or anything else that needs
361 appendfile_transport_init(transport_instance *tblock)
363 appendfile_transport_options_block *ob =
364 (appendfile_transport_options_block *)(tblock->options_block);
366 /* Set up the setup entry point, to be called in the privileged state */
368 tblock->setup = appendfile_transport_setup;
370 /* Lock_retries must be greater than zero */
372 if (ob->lock_retries == 0) ob->lock_retries = 1;
374 /* Only one of a file name or directory name must be given. */
376 if (ob->filename && ob->dirname)
377 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
378 "only one of \"file\" or \"directory\" can be specified", tblock->name);
380 /* If a file name was specified, neither quota_filecount nor quota_directory
385 if (ob->quota_filecount)
386 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
387 "quota_filecount must not be set without \"directory\"", tblock->name);
388 if (ob->quota_directory)
389 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
390 "quota_directory must not be set without \"directory\"", tblock->name);
393 /* The default locking depends on whether MBX is set or not. Change the
394 built-in default if none of the lock options has been explicitly set. At least
395 one form of locking is required in all cases, but mbx locking changes the
396 meaning of fcntl and flock locking. */
398 /* Not all operating systems provide flock(). For those that do, if flock is
399 requested, the default for fcntl is FALSE. */
404 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
405 "flock() support was not available in the operating system when this "
406 "binary was built", tblock->name);
407 #endif /* NO_FLOCK */
408 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
413 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
414 !ob->set_use_mbx_lock)
416 ob->use_lockfile = ob->use_flock = FALSE;
417 ob->use_mbx_lock = ob->use_fcntl = TRUE;
419 else if (ob->use_mbx_lock)
421 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
422 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
423 if (!ob->set_use_flock) ob->use_flock = FALSE;
424 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
426 #endif /* SUPPORT_MBX */
428 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
429 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
430 "no locking configured", tblock->name);
432 /* Unset timeouts for non-used locking types */
434 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
435 if (!ob->use_flock) ob->lock_flock_timeout = 0;
437 /* If a directory name was specified, only one of maildir or mailstore may be
438 specified, and if quota_filecount or quota_directory is given, quota must
443 if (ob->maildir_format && ob->mailstore_format)
444 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
445 "only one of maildir and mailstore may be specified", tblock->name);
446 if (ob->quota_filecount != NULL && ob->quota == NULL)
447 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
448 "quota must be set if quota_filecount is set", tblock->name);
449 if (ob->quota_directory != NULL && ob->quota == NULL)
450 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
451 "quota must be set if quota_directory is set", tblock->name);
454 /* If a fixed uid field is set, then a gid field must also be set. */
456 if (tblock->uid_set && !tblock->gid_set && !tblock->expand_gid)
457 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
458 "user set without group for the %s transport", tblock->name);
460 /* If "create_file" is set, check that a valid option is given, and set the
463 if (ob->create_file_string)
466 if (Ustrcmp(ob->create_file_string, "anywhere") == 0)
467 value = create_anywhere;
468 else if (Ustrcmp(ob->create_file_string, "belowhome") == 0)
469 value = create_belowhome;
470 else if (Ustrcmp(ob->create_file_string, "inhome") == 0)
471 value = create_inhome;
473 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
474 "invalid value given for \"file_create\" for the %s transport: %s",
475 tblock->name, ob->create_file_string);
476 ob->create_file = value;
479 /* If quota_warn_threshold is set, set up default for warn_message. It may
480 not be used if the actual threshold for a given delivery ends up as zero,
481 of if it's given as a percentage and there's no quota setting. */
483 if (ob->quota_warn_threshold)
485 if (!tblock->warn_message) tblock->warn_message = US
486 "To: $local_part@$domain\n"
487 "Subject: Your mailbox\n\n"
488 "This message is automatically created by mail delivery software (Exim).\n\n"
489 "The size of your mailbox has exceeded a warning threshold that is\n"
490 "set by the system administrator.\n";
493 /* If batch SMTP is set, force the check and escape strings, and arrange that
494 headers are also escaped. */
498 ob->check_string = US".";
499 ob->escape_string = US"..";
500 ob->options |= topt_escape_headers;
503 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
504 insert default values for for the affixes and the check/escape strings. */
506 else if (!ob->dirname && !ob->maildir_format && !ob->mailstore_format)
508 if (!ob->message_prefix) ob->message_prefix =
509 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
510 if (!ob->message_suffix) ob->message_suffix = US"\n";
511 if (!ob->check_string) ob->check_string = US"From ";
512 if (!ob->escape_string) ob->escape_string = US">From ";
516 /* Set up the bitwise options for transport_write_message from the various
517 driver options. Only one of body_only and headers_only can be set. */
520 (tblock->body_only ? topt_no_headers : 0) |
521 (tblock->headers_only ? topt_no_body : 0) |
522 (tblock->return_path_add ? topt_add_return_path : 0) |
523 (tblock->delivery_date_add ? topt_add_delivery_date : 0) |
524 (tblock->envelope_to_add ? topt_add_envelope_to : 0) |
525 ((ob->use_crlf || ob->mbx_format) ? topt_use_crlf : 0);
530 /*************************************************
532 *************************************************/
534 /* The comsat daemon is the thing that provides asynchronous notification of
535 the arrival of local messages, if requested by the user by "biff y". It is a
536 BSD thing that uses a TCP/IP protocol for communication. A message consisting
537 of the text "user@offset" must be sent, where offset is the place in the
538 mailbox where new mail starts. There is no scope for telling it which file to
539 look at, which makes it a less than useful if mail is being delivered into a
540 non-standard place such as the user's home directory. In fact, it doesn't seem
541 to pay much attention to the offset.
545 offset offset in mailbox
551 notify_comsat(uschar *user, off_t offset)
557 DEBUG(D_transport) debug_printf("notify_comsat called\n");
559 s = string_sprintf("%.200s@" OFF_T_FMT "\n", user, offset);
561 if ((sp = getservbyname("biff", "udp")) == NULL)
563 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
567 host.name = US"localhost";
571 /* This code is all set up to look up "localhost" and use all its addresses
572 until one succeeds. However, it appears that at least on some systems, comsat
573 doesn't listen on the ::1 address. So for the moment, just force the address to
574 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
575 can be changed. (But actually, comsat is probably dying out anyway.) */
578 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
580 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
585 host.address = US"127.0.0.1";
588 for (host_item * h = &host; h; h = h->next)
591 int host_af = Ustrchr(h->address, ':') != NULL ? AF_INET6 : AF_INET;
593 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
595 if ((sock = ip_socket(SOCK_DGRAM, host_af)) < 0) continue;
597 /* Connect never fails for a UDP socket, so don't set a timeout. */
599 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0, NULL);
600 rc = send(sock, s, Ustrlen(s) + 1, 0);
605 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
612 /*************************************************
613 * Check the format of a file *
614 *************************************************/
616 /* This function is called when file_format is set, to check that an existing
617 file has the right format. The format string contains text/transport pairs. The
618 string matching is literal. we just read big_buffer_size bytes, because this is
619 all about the first few bytes of a file.
623 tblock the transport block
624 addr the address block - for inserting error data
626 Returns: pointer to the required transport, or NULL
630 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
632 const uschar *format =
633 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
635 int len = read(cfd, data, sizeof(data));
639 DEBUG(D_transport) debug_printf("checking file format\n");
641 /* An empty file matches the current transport */
643 if (len == 0) return tblock;
645 /* Search the formats for a match */
647 while ((s = string_nextinlist(&format,&sep,big_buffer,big_buffer_size)))
649 int slen = Ustrlen(s);
650 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
651 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
655 for (transport_instance * tt = transports; tt; tt = tt->next)
656 if (Ustrcmp(tp, tt->name) == 0)
659 debug_printf("file format -> %s transport\n", tt->name);
662 addr->basic_errno = ERRNO_BADTRANSPORT;
663 addr->message = string_sprintf("%s transport (for %.*s format) not found",
669 /* Failed to find a match */
671 addr->basic_errno = ERRNO_FORMATUNKNOWN;
672 addr->message = US"mailbox file format unrecognized";
679 /*************************************************
680 * Check directory's files for quota *
681 *************************************************/
683 /* This function is called if quota is set for one of the delivery modes that
684 delivers into a specific directory. It scans the directory and stats all the
685 files in order to get a total size and count. This is an expensive thing to do,
686 but some people are prepared to bear the cost. Alternatively, if size_regex is
687 set, it is used as a regex to try to extract the size from the file name, a
688 strategy that some people use on maildir files on systems where the users have
691 The function is global, because it is also called from tf_maildir.c for maildir
692 folders (which should contain only regular files).
694 Note: Any problems can be written to debugging output, but cannot be written to
695 the log, because we are running as an unprivileged user here.
698 dirname the name of the directory
699 countptr where to add the file count (because this function recurses)
700 regex a compiled regex to get the size from a name
702 Returns: the sum of the sizes of the stattable files
703 zero if the directory cannot be opened
707 check_dir_size(const uschar * dirname, int *countptr, const pcre *regex)
711 int count = *countptr;
713 if (!(dir = exim_opendir(dirname))) return 0;
715 for (struct dirent *ent; ent = readdir(dir); )
717 uschar * path, * name = US ent->d_name;
720 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
724 /* If there's a regex, try to find the size using it */
729 if (pcre_exec(regex, NULL, CS name, Ustrlen(name), 0, 0, ovector,6) >= 2)
732 off_t size = (off_t)Ustrtod(name + ovector[2], &endptr);
733 if (endptr == name + ovector[3])
737 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
743 debug_printf("check_dir_size: regex did not match %s\n", name);
746 /* No regex or no match for the regex, or captured non-digits */
748 path = string_sprintf("%s/%s", dirname, name);
750 if (Ustat(path, &statbuf) < 0)
753 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, path,
757 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
758 sum += statbuf.st_size / statbuf.st_nlink;
759 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
760 sum += check_dir_size(path, &count, regex);
765 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
775 /*************************************************
776 * Apply a lock to a file descriptor *
777 *************************************************/
779 /* This function applies a lock to a file descriptor, using a blocking or
780 non-blocking lock, depending on the timeout value. It can apply either or
781 both of a fcntl() and a flock() lock. However, not all OS support flock();
782 for those that don't, the use_flock option cannot be set.
785 fd the file descriptor
786 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
787 fcntl() format); the flock() type is deduced if needed
788 dofcntl do fcntl() locking
789 fcntltime non-zero to use blocking fcntl()
790 doflock do flock() locking
791 flocktime non-zero to use blocking flock()
793 Returns: yield of the fcntl() or flock() call, with errno preserved;
794 sigalrm_seen set if there has been a timeout
798 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
803 struct flock lock_data;
804 lock_data.l_type = fcntltype;
805 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
807 sigalrm_seen = FALSE;
814 yield = fcntl(fd, F_SETLKW, &lock_data);
819 else yield = fcntl(fd, F_SETLK, &lock_data);
823 if (doflock && (yield >= 0))
825 int flocktype = (fcntltype == F_WRLCK) ? LOCK_EX : LOCK_SH;
829 yield = flock(fd, flocktype);
834 else yield = flock(fd, flocktype | LOCK_NB);
836 #endif /* NO_FLOCK */
845 /*************************************************
846 * Copy message into MBX mailbox *
847 *************************************************/
849 /* This function is called when a message intended for a MBX mailbox has been
850 written to a temporary file. We can now get the size of the message and then
851 copy it in MBX format to the mailbox.
854 to_fd fd to write to (the real mailbox)
855 from_fd fd to read from (the temporary file)
856 saved_size current size of mailbox
858 Returns: OK if all went well, DEFER otherwise, with errno preserved
859 the number of bytes written are added to transport_count
860 by virtue of calling transport_write_block()
863 /* Values taken from c-client */
865 #define MBX_HDRSIZE 2048
866 #define MBX_NUSERFLAGS 30
869 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
874 transport_ctx tctx = { .u={.fd = to_fd}, .options = topt_not_socket };
876 /* If the current mailbox size is zero, write a header block */
881 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
882 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
883 (long int)time(NULL));
884 for (int i = 0; i < MBX_NUSERFLAGS; i++)
885 sprintf (CS(s += Ustrlen(s)), "\015\012");
886 if (!transport_write_block (&tctx, deliver_out_buffer, MBX_HDRSIZE, FALSE))
890 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
892 /* Now construct the message's header from the time and the RFC822 file
893 size, including CRLFs, which is the size of the input (temporary) file. */
895 if (fstat(from_fd, &statbuf) < 0) return DEFER;
896 size = statbuf.st_size;
898 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
899 tod_stamp(tod_mbx), size, 0L, 0, 0);
900 used = Ustrlen(deliver_out_buffer);
902 /* Rewind the temporary file, and copy it over in chunks. */
904 if (lseek(from_fd, 0 , SEEK_SET) < 0) return DEFER;
908 int len = read(from_fd, deliver_out_buffer + used,
909 DELIVER_OUT_BUFFER_SIZE - used);
912 if (len == 0) errno = ERRNO_MBXLENGTH;
915 if (!transport_write_block(&tctx, deliver_out_buffer, used + len, FALSE))
923 #endif /* SUPPORT_MBX */
927 /*************************************************
928 * Check creation is permitted *
929 *************************************************/
931 /* This function checks whether a given file name is permitted to be created,
932 as controlled by the create_file option. If no home directory is set, however,
933 we can't do any tests.
936 filename the file name
937 create_file the ob->create_file option
939 Returns: TRUE if creation is permitted
943 check_creation(uschar *filename, int create_file)
947 if (deliver_home && create_file != create_anywhere)
949 int len = Ustrlen(deliver_home);
950 uschar *file = filename;
952 while (file[0] == '/' && file[1] == '/') file++;
953 if (Ustrncmp(file, deliver_home, len) != 0 || file[len] != '/' ||
954 ( Ustrchr(file+len+2, '/') != NULL &&
956 create_file != create_belowhome ||
957 Ustrstr(file+len, "/../") != NULL
962 /* If yield is TRUE, the file name starts with the home directory, and does
963 not contain any instances of "/../" in the "belowhome" case. However, it may
964 still contain symbolic links. We can check for this by making use of
965 realpath(), which most Unixes seem to have (but make it possible to cut this
966 out). We can't just use realpath() on the whole file name, because we know
967 the file itself doesn't exist, and intermediate directories may also not
968 exist. What we want to know is the real path of the longest existing part of
969 the path. That must match the home directory's beginning, whichever is the
973 if (yield && create_file == create_belowhome)
977 for (uschar * slash = Ustrrchr(file, '/'); /* There is known to be one */
978 !rp && slash > file; /* Stop if reached beginning */
982 rp = US realpath(CS file, CS big_buffer);
983 next = Ustrrchr(file, '/');
987 /* If rp == NULL it means that none of the relevant directories exist.
988 This is not a problem here - it means that no symbolic links can exist,
989 which is all we are worried about. Otherwise, we must compare it
990 against the start of the home directory. However, that may itself
991 contain symbolic links, so we have to "realpath" it as well, if
996 uschar hdbuffer[PATH_MAX+1];
997 uschar *rph = deliver_home;
998 int rlen = Ustrlen(big_buffer);
1000 if ((rp = US realpath(CS deliver_home, CS hdbuffer)))
1006 if (rlen > len) rlen = len;
1007 if (Ustrncmp(rph, big_buffer, rlen) != 0)
1010 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
1011 big_buffer, deliver_home);
1015 #endif /* NO_REALPATH */
1023 /*************************************************
1024 * Main entry point *
1025 *************************************************/
1027 /* See local README for general interface details. This transport always
1028 returns FALSE, indicating that the status which has been placed in the first
1029 address should be copied to any other addresses in a batch.
1031 Appendfile delivery is tricky and has led to various security problems in other
1032 mailers. The logic used here is therefore laid out in some detail. When this
1033 function is called, we are running in a subprocess which has had its gid and
1034 uid set to the appropriate values. Therefore, we cannot write directly to the
1035 exim logs. Any errors must be handled by setting appropriate return codes.
1036 Note that the default setting for addr->transport_return is DEFER, so it need
1037 not be set unless some other value is required.
1039 The code below calls geteuid() rather than getuid() to get the current uid
1040 because in weird configurations not running setuid root there may be a
1041 difference. In the standard configuration, where setuid() has been used in the
1042 delivery process, there will be no difference between the uid and the euid.
1044 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1045 alias expansion. Otherwise, there must be a configured file name or
1048 The following items apply in the case when a file name (as opposed to a
1049 directory name) is given, that is, when appending to a single file:
1051 (2f) Expand the file name.
1053 (3f) If the file name is /dev/null, return success (optimization).
1055 (4f) If the file_format options is set, open the file for reading, and check
1056 that the bytes at the start of the file match one of the given strings.
1057 If the check indicates a transport other than the current one should be
1058 used, pass control to that other transport. Otherwise continue. An empty
1059 or non-existent file matches the current transport. The file is closed
1062 (5f) If a lock file is required, create it (see extensive separate comments
1063 below about the algorithm for doing this). It is important to do this
1064 before opening the mailbox if NFS is in use.
1066 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1067 details of any symbolic link.
1069 (7f) If the file already exists:
1071 Check the owner and group if necessary, and defer if they are wrong.
1073 If it is a symbolic link AND the allow_symlink option is set (NOT the
1074 default), go back to (6f) but this time use stat() instead of lstat().
1076 If it's not a regular file (or FIFO when permitted), defer delivery.
1078 Check permissions. If the required permissions are *less* than the
1079 existing ones, or supplied by the address (often by the user via filter),
1080 chmod() the file. Otherwise, defer.
1082 Save the inode number.
1084 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1086 If open fails because the file does not exist, go to (6f); on any other
1089 Check the inode number hasn't changed - I realize this isn't perfect (an
1090 inode can be reused) but it's cheap and will catch some of the races.
1092 Check it's still a regular file (or FIFO if permitted).
1094 Check that the owner and permissions haven't changed.
1096 If file_format is set, check that the file still matches the format for
1097 the current transport. If not, defer delivery.
1099 (8f) If file does not exist initially:
1101 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1102 this is via a symbolic link (only possible if allow_symlinks is set), in
1103 which case don't use O_EXCL, as it doesn't work.
1105 If open fails because the file already exists, go to (6f). To avoid
1106 looping for ever in a situation where the file is continuously being
1107 created and deleted, all of this happens inside a loop that operates
1108 lock_retries times and includes the fcntl and flock locking. If the
1109 loop completes without the file getting opened, defer and request
1110 freezing, because something really weird is happening.
1112 If open fails for any other reason, defer for subsequent delivery except
1113 when this is a file delivery resulting from an alias or forward expansion
1114 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1115 most likely a user rather than a configuration error.
1117 (9f) We now have the file checked and open for writing. If so configured, lock
1118 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1119 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1120 still fails, give up and defer delivery.
1122 (10f)Save the access time (for subsequent restoration) and the size of the
1123 file, for comsat and for re-setting if delivery fails in the middle -
1124 e.g. for quota exceeded.
1126 The following items apply in the case when a directory name is given:
1128 (2d) Create a new file in the directory using a temporary name, by opening for
1129 writing and with O_CREAT. If maildir format is being used, the file
1130 is created in a temporary subdirectory with a prescribed name. If
1131 mailstore format is being used, the envelope file is first created with a
1132 temporary name, then the data file.
1134 The following items apply in all cases:
1136 (11) We now have the file open for writing, and locked if it was given as a
1137 file name. Write the message and flush the file, unless there is a setting
1138 of the local quota option, in which case we can check for its excession
1139 without doing any writing.
1141 In the case of MBX format mailboxes, the message is first written to a
1142 temporary file, in order to get its correct length. This is then copied to
1143 the real file, preceded by an MBX header.
1145 If there is a quota error on writing, defer the address. Timeout logic
1146 will determine for how long retries are attempted. We restore the mailbox
1147 to its original length if it's a single file. There doesn't seem to be a
1148 uniform error code for quota excession (it even differs between SunOS4
1149 and some versions of SunOS5) so a system-dependent macro called
1150 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1153 For any other error (most commonly disk full), do the same.
1155 The following applies after appending to a file:
1157 (12f)Restore the atime; notify_comsat if required; close the file (which
1158 unlocks it if it was locked). Delete the lock file if it exists.
1160 The following applies after writing a unique file in a directory:
1162 (12d)For maildir format, rename the file into the new directory. For mailstore
1163 format, rename the envelope file to its correct name. Otherwise, generate
1164 a unique name from the directory_file option, and rename to that, possibly
1165 trying a few times if the file exists and re-expanding the name gives a
1168 This transport yields FAIL only when a file name is generated by an alias or
1169 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1170 All other failures return DEFER (in addr->transport_return). */
1174 appendfile_transport_entry(
1175 transport_instance *tblock, /* data for this instantiation */
1176 address_item *addr) /* address we are working on */
1178 appendfile_transport_options_block *ob =
1179 (appendfile_transport_options_block *)(tblock->options_block);
1180 struct stat statbuf;
1181 uschar *fdname = NULL;
1182 uschar *filename = NULL;
1183 uschar *hitchname = NULL;
1184 uschar *dataname = NULL;
1185 uschar *lockname = NULL;
1186 uschar *newname = NULL;
1187 uschar *nametag = NULL;
1189 uschar *filecount_msg = US"";
1191 struct utimbuf times;
1192 struct timeval msg_tv;
1193 BOOL disable_quota = FALSE;
1194 BOOL isdirectory = FALSE;
1195 BOOL isfifo = FALSE;
1196 BOOL wait_for_tick = FALSE;
1197 uid_t uid = geteuid(); /* See note above */
1198 gid_t gid = getegid();
1200 int mode = (addr->mode > 0) ? addr->mode : ob->mode;
1201 off_t saved_size = -1;
1202 off_t mailbox_size = ob->mailbox_size_value;
1203 int mailbox_filecount = ob->mailbox_filecount_value;
1211 int mbx_lockfd = -1;
1212 uschar mbx_lockname[40];
1213 FILE *temp_file = NULL;
1214 #endif /* SUPPORT_MBX */
1216 #ifdef SUPPORT_MAILDIR
1217 int maildirsize_fd = -1; /* fd for maildirsize file */
1218 int maildir_save_errno;
1222 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1224 /* An "address_file" or "address_directory" transport is used to deliver to
1225 files specified via .forward or an alias file. Prior to release 4.20, the
1226 "file" and "directory" options were ignored in this case. This has been changed
1227 to allow the redirection data to specify what is in effect a folder, whose
1228 location is determined by the options on the transport.
1230 Compatibility with the case when neither option is set is retained by forcing a
1231 value for the file or directory name. A directory delivery is assumed if the
1232 last character of the path from the router is '/'.
1234 The file path is in the local part of the address, but not in the $local_part
1235 variable (that holds the parent local part). It is, however, in the
1236 $address_file variable. Below, we update the local part in the address if it
1237 changes by expansion, so that the final path ends up in the log. */
1239 if (testflag(addr, af_file) && !ob->filename && !ob->dirname)
1241 fdname = US"$address_file";
1242 if (address_file[Ustrlen(address_file)-1] == '/' ||
1243 ob->maildir_format ||
1244 ob->mailstore_format)
1248 /* Handle (a) an "address file" delivery where "file" or "directory" is
1249 explicitly set and (b) a non-address_file delivery, where one of "file" or
1250 "directory" must be set; initialization ensures that they are not both set. */
1254 if (!(fdname = ob->filename))
1256 fdname = ob->dirname;
1261 addr->message = string_sprintf("Mandatory file or directory option "
1262 "missing from %s transport", tblock->name);
1267 /* Maildir and mailstore require a directory */
1269 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1271 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1272 "to be specified for the %s transport",
1273 ob->maildir_format ? "dir" : "store", tblock->name);
1277 if (!(path = expand_string(fdname)))
1279 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1280 "name for %s transport) failed: %s", fdname, tblock->name,
1281 expand_string_message);
1284 if (is_tainted(path))
1286 addr->message = string_sprintf("Tainted '%s' (file or directory "
1287 "name for %s transport) not permitted", path, tblock->name);
1293 addr->message = string_sprintf("appendfile: file or directory name "
1294 "\"%s\" is not absolute", path);
1295 addr->basic_errno = ERRNO_NOTABSOLUTE;
1299 /* For a file delivery, make sure the local part in the address(es) is updated
1300 to the true local part. */
1302 if (testflag(addr, af_file))
1303 for (address_item * addr2 = addr; addr2; addr2 = addr2->next)
1304 addr2->local_part = string_copy(path);
1306 /* The available mailbox formats depend on whether it is a directory or a file
1312 #ifdef SUPPORT_MAILDIR
1313 ob->maildir_format ? mbf_maildir :
1315 #ifdef SUPPORT_MAILSTORE
1316 ob->mailstore_format ? mbf_mailstore :
1324 ob->mbx_format ? mbf_mbx :
1331 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1333 " warning=" OFF_T_FMT "%s\n"
1334 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1335 "maildir_use_size_file=%s\n",
1336 mode, ob->notify_comsat, ob->quota_value,
1337 ob->quota_no_check ? " (no_check)" : "",
1338 ob->quota_filecount_no_check ? " (no_check_filecount)" : "",
1339 ob->quota_warn_threshold_value,
1340 ob->quota_warn_threshold_is_percent ? "%" : "",
1341 isdirectory ? "directory" : "file",
1342 path, mailbox_formats[mbformat],
1343 !ob->message_prefix ? US"null" : string_printing(ob->message_prefix),
1344 !ob->message_suffix ? US"null" : string_printing(ob->message_suffix),
1345 ob->maildir_use_size_file ? "yes" : "no");
1347 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1348 ob->use_lockfile ? "lockfile " : "",
1349 ob->use_mbx_lock ? "mbx locking (" : "",
1350 ob->use_fcntl ? "fcntl " : "",
1351 ob->use_flock ? "flock" : "",
1352 ob->use_mbx_lock ? ")" : "");
1355 /* If the -N option is set, can't do any more. */
1360 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1362 addr->transport_return = OK;
1366 /* Handle the case of a file name. If the file name is /dev/null, we can save
1367 ourselves some effort and just give a success return right away. */
1371 BOOL use_lstat = TRUE;
1372 BOOL file_opened = FALSE;
1373 BOOL allow_creation_here = TRUE;
1375 if (Ustrcmp(path, "/dev/null") == 0)
1377 addr->transport_return = OK;
1381 /* Set the name of the file to be opened, and the file to which the data
1382 is written, and find out if we are permitted to create a non-existent file. */
1384 dataname = filename = path;
1385 allow_creation_here = check_creation(filename, ob->create_file);
1387 /* If ob->create_directory is set, attempt to create the directories in
1388 which this mailbox lives, but only if we are permitted to create the file
1389 itself. We know we are dealing with an absolute path, because this was
1392 if (ob->create_directory && allow_creation_here)
1394 uschar *p = Ustrrchr(path, '/');
1396 if (!directory_make(NULL, path, ob->dirmode, FALSE))
1398 addr->basic_errno = errno;
1400 string_sprintf("failed to create directories for %s: %s", path,
1402 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1408 /* If file_format is set we must check that any existing file matches one of
1409 the configured formats by checking the bytes it starts with. A match then
1410 indicates a specific transport - if it is not this one, pass control to it.
1411 Otherwise carry on here. An empty or non-existent file matches the current
1412 transport. We don't need to distinguish between non-existence and other open
1413 failures because if an existing file fails to open here, it will also fail
1414 again later when O_RDWR is used. */
1416 if (ob->file_format)
1418 int cfd = Uopen(path, O_RDONLY, 0);
1421 transport_instance *tt = check_file_format(cfd, tblock, addr);
1424 /* If another transport is indicated, call it and return; if no transport
1425 was found, just return - the error data will have been set up.*/
1431 set_process_info("delivering %s to %s using %s", message_id,
1432 addr->local_part, tt->name);
1433 debug_print_string(tt->debug_string);
1434 addr->transport = tt;
1435 (tt->info->code)(tt, addr);
1442 /* The locking of mailbox files is worse than the naming of cats, which is
1443 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1444 three different names, so several different styles of locking are used.
1446 Research in other programs that lock mailboxes shows that there is no
1447 universally standard method. Having mailboxes NFS-mounted on the system that
1448 is delivering mail is not the best thing, but people do run like this,
1449 and so the code must do its best to cope.
1451 Three different locking mechanisms are supported. The initialization function
1452 checks that at least one is configured.
1456 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1457 will work over NFS. Only after that is done do we actually open the mailbox
1458 and apply locks to it (if configured).
1460 Originally, Exim got the file opened before doing anything about locking.
1461 However, a very occasional problem was observed on Solaris 2 when delivering
1462 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1463 gets remembered at open time. If another process on another host (that's
1464 important) has the file open and locked and writes to it and then releases
1465 the lock while the first process is waiting to get the lock, the first
1466 process may fail to write at the new end point of the file - despite the very
1467 definite statement about O_APPEND in the man page for write(). Experiments
1468 have reproduced this problem, but I do not know any way of forcing a host to
1469 update its attribute cache for an open NFS file. It would be nice if it did
1470 so when a lock was taken out, but this does not seem to happen. Anyway, to
1471 reduce the risk of this problem happening, we now create the lock file
1472 (if configured) *before* opening the mailbox. That will prevent two different
1473 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1474 however, but Pine at least seems to operate in the same way.
1476 Lockfiles should normally be used when NFS is involved, because of the above
1479 The logic for creating the lock file is:
1481 . The name of the lock file is <mailbox-name>.lock
1483 . First, create a "hitching post" name by adding the primary host name,
1484 current time and pid to the lock file name. This should be unique.
1486 . Create the hitching post file using WRONLY + CREAT + EXCL.
1488 . If that fails EACCES, we assume it means that the user is unable to create
1489 files in the mail spool directory. Some installations might operate in this
1490 manner, so there is a configuration option to allow this state not to be an
1491 error - we proceed to lock using fcntl only, after the file is open.
1493 . Otherwise, an error causes a deferment of the address.
1495 . Hard link the hitching post to the lock file name.
1497 . If the link succeeds, we have successfully created the lock file. Simply
1498 close and unlink the hitching post file.
1500 . If the link does not succeed, proceed as follows:
1502 o Fstat the hitching post file, and then close and unlink it.
1504 o Now examine the stat data. If the number of links to the file is exactly
1505 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1506 the return never made it back, so the link() function gave a failure
1509 . This method allows for the lock file to be created by some other process
1510 right up to the moment of the attempt to hard link it, and is also robust
1511 against NFS server crash-reboots, which would probably result in timeouts
1512 in the middle of link().
1514 . System crashes may cause lock files to get left lying around, and some means
1515 of flushing them is required. The approach of writing a pid (used by smail
1516 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1517 timeout, which seems a better approach. Since any program that writes to a
1518 mailbox using a lock file should complete its task very quickly, Pine
1519 removes lock files that are older than 5 minutes. We allow the value to be
1520 configurable on the transport.
1524 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1525 mailbox once it is open. This is done by default with a non-blocking lock.
1526 Failures to lock cause retries after a sleep, but only for a certain number
1527 of tries. A blocking lock is deliberately not used so that we don't hold the
1528 mailbox open. This minimizes the possibility of the NFS problem described
1529 under LOCK FILES above, if for some reason NFS deliveries are happening
1530 without lock files. However, the use of a non-blocking lock and sleep, though
1531 the safest approach, does not give the best performance on very busy systems.
1532 A blocking lock plus timeout does better. Therefore Exim has an option to
1533 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1534 enables the use of blocking fcntl() calls.
1538 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1539 same manner as for fcntl locking above. No-blocking/timeout is also set as
1540 above in lock_flock_timeout. Not all operating systems provide or support
1541 flock(). For those that don't (as determined by the definition of LOCK_SH in
1542 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1543 is implemented (not precisely) on top of fcntl(), which means there's no
1544 point in actually using it.
1548 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1549 then the rules used for locking in c-client are used. Exim takes out a shared
1550 lock on the mailbox file, and an exclusive lock on the file whose name is
1551 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1552 any other MBX client from getting an exclusive lock on it and expunging it.
1553 It also stops any other MBX client from unlinking the /tmp lock when it has
1556 The exclusive lock on the /tmp file prevents any other MBX client from
1557 updating the mailbox in any way. When writing is finished, if an exclusive
1558 lock on the mailbox can be obtained, indicating there are no current sharers,
1559 the /tmp file is unlinked.
1561 MBX locking can use either fcntl() or flock() locking. If neither
1562 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1563 The calls for getting these locks are by default non-blocking, as for non-mbx
1564 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1565 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1566 probably makes sense to set timeouts for any MBX deliveries. */
1569 /* Build a lock file if configured to do so - the existence of a lock
1570 file is subsequently checked by looking for a non-negative value of the
1571 file descriptor hd - even though the file is no longer open. */
1573 if (ob->use_lockfile)
1575 /* cf. exim_lock.c */
1576 lockname = string_sprintf("%s.lock", filename);
1577 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1578 (unsigned int)(time(NULL)), (unsigned int)getpid());
1580 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1583 /* Lock file creation retry loop */
1585 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1589 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1592 addr->basic_errno = errno;
1594 string_sprintf("creating lock file hitching post %s "
1595 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1596 (long int)getegid());
1600 /* Attempt to hitch the hitching post to the lock file. If link()
1601 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1602 file, and get rid of the hitching post. If the number of links was 2,
1603 the link was created, despite the failure of link(). If the hitch was
1604 not successful, try again, having unlinked the lock file if it is too
1607 There's a version of Linux (2.0.27) which doesn't update its local cache
1608 of the inode after link() by default - which many think is a bug - but
1609 if the link succeeds, this code will be OK. It just won't work in the
1610 case when link() fails after having actually created the link. The Linux
1611 NFS person is fixing this; a temporary patch is available if anyone is
1612 sufficiently worried. */
1614 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1617 if (rc != 0 && statbuf.st_nlink != 2)
1619 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1620 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1622 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1625 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1629 DEBUG(D_transport) debug_printf("lock file created\n");
1633 /* Check for too many tries at creating the lock file */
1635 if (i >= ob->lock_retries)
1637 addr->basic_errno = ERRNO_LOCKFAILED;
1638 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1645 /* We now have to get the file open. First, stat() it and act on existence or
1646 non-existence. This is in a loop to handle the case of a file's being created
1647 or deleted as we watch, and also to handle retries when the locking fails.
1648 Rather than holding the file open while waiting for the fcntl() and/or
1649 flock() lock, we close and do the whole thing again. This should be safer,
1650 especially for NFS files, which might get altered from other hosts, making
1651 their cached sizes incorrect.
1653 With the default settings, no symlinks are permitted, but there is an option
1654 to permit symlinks for those sysadmins that know what they are doing.
1655 Shudder. However, insist that the initial symlink is owned by the right user.
1656 Thus lstat() is used initially; if a symlink is discovered, the loop is
1657 repeated such that stat() is used, to look at the end file. */
1659 for (i = 0; i < ob->lock_retries; i++)
1661 int sleep_before_retry = TRUE;
1662 file_opened = FALSE;
1664 if ((use_lstat ? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1666 /* Let's hope that failure to stat (other than non-existence) is a
1669 if (errno != ENOENT)
1671 addr->basic_errno = errno;
1672 addr->message = string_sprintf("attempting to stat mailbox %s",
1677 /* File does not exist. If it is required to pre-exist this state is an
1680 if (ob->file_must_exist)
1682 addr->basic_errno = errno;
1683 addr->message = string_sprintf("mailbox %s does not exist, "
1684 "but file_must_exist is set", filename);
1688 /* If not permitted to create this file because it isn't in or below
1689 the home directory, generate an error. */
1691 if (!allow_creation_here)
1693 addr->basic_errno = ERRNO_BADCREATE;
1694 addr->message = string_sprintf("mailbox %s does not exist, "
1695 "but creation outside the home directory is not permitted",
1700 /* Attempt to create and open the file. If open fails because of
1701 pre-existence, go round the loop again. For any other error, defer the
1702 address, except for an alias or forward generated file name with EPERM,
1703 ENOENT, or EACCES, as those are most likely to be user errors rather
1704 than Exim config errors. When a symbolic link is permitted and points
1705 to a non-existent file, we get here with use_lstat = FALSE. In this case
1706 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1707 consistency and because MBX locking requires it in order to be able to
1708 get a shared lock. */
1710 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1711 (use_lstat ? O_EXCL : 0), mode);
1714 if (errno == EEXIST) continue;
1715 addr->basic_errno = errno;
1716 addr->message = string_sprintf("while creating mailbox %s",
1718 if (testflag(addr, af_file) &&
1719 (errno == EPERM || errno == ENOENT || errno == EACCES))
1720 addr->transport_return = FAIL;
1724 /* We have successfully created and opened the file. Ensure that the group
1725 and the mode are correct. */
1727 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
1729 addr->basic_errno = errno;
1730 addr->message = string_sprintf("while setting perms on mailbox %s",
1732 addr->transport_return = FAIL;
1738 /* The file already exists. Test its type, ownership, and permissions, and
1739 save the inode for checking later. If symlinks are permitted (not the
1740 default or recommended state) it may be a symlink that already exists.
1741 Check its ownership and then look for the file at the end of the link(s).
1742 This at least prevents one user creating a symlink for another user in
1743 a sticky directory. */
1747 int oldmode = (int)statbuf.st_mode;
1748 ino_t inode = statbuf.st_ino;
1749 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1751 isfifo = FALSE; /* In case things are changing */
1753 /* Check owner if required - the default. */
1755 if (ob->check_owner && statbuf.st_uid != uid)
1757 addr->basic_errno = ERRNO_BADUGID;
1758 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1759 "(%ld != %ld)", filename,
1760 islink ? " (symlink)" : "",
1761 (long int)(statbuf.st_uid), (long int)uid);
1765 /* Group is checked only if check_group is set. */
1767 if (ob->check_group && statbuf.st_gid != gid)
1769 addr->basic_errno = ERRNO_BADUGID;
1770 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1771 filename, islink ? " (symlink)" : "", statbuf.st_gid, gid);
1775 /* Just in case this is a sticky-bit mail directory, we don't want
1776 users to be able to create hard links to other users' files. */
1778 if (statbuf.st_nlink != 1)
1780 addr->basic_errno = ERRNO_NOTREGULAR;
1781 addr->message = string_sprintf("mailbox %s%s has too many links (%d)",
1782 filename, islink ? " (symlink)" : "", statbuf.st_nlink);
1787 /* If symlinks are permitted (not recommended), the lstat() above will
1788 have found the symlink. Its ownership has just been checked; go round
1789 the loop again, using stat() instead of lstat(). That will never yield a
1792 if (islink && ob->allow_symlink)
1795 i--; /* Don't count this time round */
1799 /* An actual file exists. Check that it is a regular file, or FIFO
1802 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1804 else if ((oldmode & S_IFMT) != S_IFREG)
1806 addr->basic_errno = ERRNO_NOTREGULAR;
1807 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1808 filename, ob->allow_fifo ? " or named pipe" : "");
1812 /* If the mode is not what it would be for a newly created file, change
1813 the permissions if the mode is supplied for the address. Otherwise,
1814 reduce but do not extend the permissions. If the newly created
1815 permissions are greater than the existing permissions, don't change
1816 things when the mode is not from the address. */
1818 if ((oldmode &= 07777) != mode)
1820 int diffs = oldmode ^ mode;
1821 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1823 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1824 if (Uchmod(filename, mode) < 0)
1826 addr->basic_errno = errno;
1827 addr->message = string_sprintf("attempting to chmod mailbox %s",
1834 /* Mode not from address, and newly-created permissions are greater
1835 than existing permissions. Default is to complain, but it can be
1836 configured to go ahead and try to deliver anyway if that's what
1837 the administration wants. */
1839 else if (ob->mode_fail_narrower)
1841 addr->basic_errno = ERRNO_BADMODE;
1842 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1843 "(%o expected)", filename, oldmode, mode);
1848 /* We are happy with the existing file. Open it, and then do further
1849 tests to ensure that it is the same file that we were just looking at.
1850 If the file does not now exist, restart this loop, going back to using
1851 lstat again. For an NFS error, just defer; other opening errors are
1852 more serious. The file is opened RDWR so that its format can be checked,
1853 and also MBX locking requires the use of a shared (read) lock. However,
1854 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1855 reading the pipe. */
1857 fd = Uopen(filename, isfifo ? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1861 if (errno == ENOENT)
1866 addr->basic_errno = errno;
1868 addr->message = string_sprintf("while opening named pipe %s "
1869 "(could mean no process is reading it)", filename);
1870 else if (errno != EWOULDBLOCK)
1871 addr->message = string_sprintf("while opening mailbox %s", filename);
1875 /* This fstat really shouldn't fail, as we have an open file! There's a
1876 dilemma here. We use fstat in order to be sure we are peering at the file
1877 we have got open. However, that won't tell us if the file was reached
1878 via a symbolic link. We checked this above, but there is a race exposure
1879 if the link was created between the previous lstat and the open. However,
1880 it would have to be created with the same inode in order to pass the
1881 check below. If ob->allow_symlink is set, causing the use of stat rather
1882 than lstat above, symbolic links may be there anyway, and the checking is
1885 if (fstat(fd, &statbuf) < 0)
1887 addr->basic_errno = errno;
1888 addr->message = string_sprintf("attempting to stat open mailbox %s",
1893 /* Check the inode; this is isn't a perfect check, but gives some
1896 if (inode != statbuf.st_ino)
1898 addr->basic_errno = ERRNO_INODECHANGED;
1899 addr->message = string_sprintf("opened mailbox %s inode number changed "
1900 "from " INO_T_FMT " to " INO_T_FMT, filename, inode, statbuf.st_ino);
1901 addr->special_action = SPECIAL_FREEZE;
1905 /* Check it's still a regular file or FIFO, and the uid, gid, and
1906 permissions have not changed. */
1908 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1909 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1911 addr->basic_errno = ERRNO_NOTREGULAR;
1913 string_sprintf("opened mailbox %s is no longer a %s", filename,
1914 isfifo ? "named pipe" : "regular file");
1915 addr->special_action = SPECIAL_FREEZE;
1919 if ((ob->check_owner && statbuf.st_uid != uid) ||
1920 (ob->check_group && statbuf.st_gid != gid))
1922 addr->basic_errno = ERRNO_BADUGID;
1924 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
1925 addr->special_action = SPECIAL_FREEZE;
1929 if ((statbuf.st_mode & 07777) != oldmode)
1931 addr->basic_errno = ERRNO_BADMODE;
1932 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
1933 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
1934 addr->special_action = SPECIAL_FREEZE;
1938 /* If file_format is set, check that the format of the file has not
1939 changed. Error data is set by the testing function. */
1941 if (ob->file_format && check_file_format(fd, tblock, addr) != tblock)
1943 addr->message = US"open mailbox has changed format";
1947 /* The file is OK. Carry on to do the locking. */
1950 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
1951 locking rules if configured to do so. If a lock file is also required, it
1952 was created above and hd was left >= 0. At least one form of locking is
1953 required by the initialization function. If locking fails here, close the
1954 file and go round the loop all over again, after waiting for a bit, unless
1955 blocking locking was used. */
1958 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
1959 sleep_before_retry = FALSE;
1961 /* Simple fcntl() and/or flock() locking */
1963 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
1965 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1966 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
1969 /* MBX locking rules */
1972 else if (ob->use_mbx_lock)
1975 struct stat lstatbuf, statbuf2;
1976 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
1977 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
1978 fstat(fd, &statbuf) >= 0)
1980 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
1981 (long)statbuf.st_ino);
1984 * 2010-05-29: SECURITY
1985 * Dan Rosenberg reported the presence of a race-condition in the
1986 * original code here. Beware that many systems still allow symlinks
1987 * to be followed in /tmp so an attacker can create a symlink pointing
1988 * elsewhere between a stat and an open, which we should avoid
1991 * It's unfortunate that we can't just use all the heavily debugged
1992 * locking from above.
1994 * Also: remember to mirror changes into exim_lock.c */
1996 /* first leave the old pre-check in place, it provides better
1997 * diagnostics for common cases */
1998 if (Ulstat(mbx_lockname, &statbuf) >= 0)
2000 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
2002 addr->basic_errno = ERRNO_LOCKFAILED;
2003 addr->message = string_sprintf("symbolic link on MBX lock file %s",
2007 if (statbuf.st_nlink > 1)
2009 addr->basic_errno = ERRNO_LOCKFAILED;
2010 addr->message = string_sprintf("hard link to MBX lock file %s",
2016 /* If we could just declare "we must be the ones who create this
2017 * file" then a hitching post in a subdir would work, since a
2018 * subdir directly in /tmp/ which we create wouldn't follow links
2019 * but this isn't our locking logic, so we can't safely change the
2020 * file existence rules. */
2022 /* On systems which support O_NOFOLLOW, it's the easiest and most
2023 * obviously correct security fix */
2024 mbx_tmp_oflags = O_RDWR | O_CREAT;
2026 mbx_tmp_oflags |= O_NOFOLLOW;
2028 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
2031 addr->basic_errno = ERRNO_LOCKFAILED;
2032 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2033 mbx_lockname, strerror(errno));
2037 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2039 addr->basic_errno = ERRNO_LOCKFAILED;
2040 addr->message = string_sprintf("attempting to lstat open MBX "
2041 "lock file %s: %s", mbx_lockname, strerror(errno));
2044 if (fstat(mbx_lockfd, &statbuf2) < 0)
2046 addr->basic_errno = ERRNO_LOCKFAILED;
2047 addr->message = string_sprintf("attempting to stat fd of open MBX "
2048 "lock file %s: %s", mbx_lockname, strerror(errno));
2054 * statbuf: if exists, is file which existed prior to opening the
2055 * lockfile, might have been replaced since then
2056 * statbuf2: result of stat'ing the open fd, is what was actually
2058 * lstatbuf: result of lstat'ing the filename immediately after
2059 * the open but there's a race condition again between
2060 * those two steps: before open, symlink to foo, after
2061 * open but before lstat have one of:
2062 * * was no symlink, so is the opened file
2063 * (we created it, no messing possible after that point)
2065 * * symlink elsewhere
2066 * * hardlink elsewhere
2068 * Don't want to compare to device of /tmp because some modern systems
2069 * have regressed to having /tmp be the safe actual filesystem as
2070 * valuable data, so is mostly worthless, unless we assume that *only*
2071 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2072 * for further consideration.
2073 * No point in doing a readlink on the lockfile as that will always be
2074 * at a different point in time from when we open it, so tells us
2075 * nothing; attempts to clean up and delete after ourselves would risk
2076 * deleting a *third* filename.
2078 if ((statbuf2.st_nlink > 1) ||
2079 (lstatbuf.st_nlink > 1) ||
2080 (!S_ISREG(lstatbuf.st_mode)) ||
2081 (lstatbuf.st_dev != statbuf2.st_dev) ||
2082 (lstatbuf.st_ino != statbuf2.st_ino))
2084 addr->basic_errno = ERRNO_LOCKFAILED;
2085 addr->message = string_sprintf("RACE CONDITION detected: "
2086 "mismatch post-initial-checks between \"%s\" and opened "
2087 "fd lead us to abort!", mbx_lockname);
2091 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2093 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2094 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2096 struct stat ostatbuf;
2098 /* This tests for a specific race condition. Ensure that we still
2099 have the same file. */
2101 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2102 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2103 statbuf.st_dev == ostatbuf.st_dev &&
2104 statbuf.st_ino == ostatbuf.st_ino)
2106 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2107 "between creation and locking\n", mbx_lockname);
2110 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2112 (void)close(mbx_lockfd);
2117 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2118 filename, strerror(errno));
2121 #endif /* SUPPORT_MBX */
2123 else break; /* No on-file locking required; break the open/lock loop */
2126 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2130 use_lstat = TRUE; /* Reset to use lstat first */
2133 /* If a blocking call timed out, break the retry loop if the total time
2134 so far is not less than than retries * interval. Use the larger of the
2135 flock() and fcntl() timeouts. */
2138 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2139 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2140 ob->lock_retries * ob->lock_interval)
2141 i = ob->lock_retries;
2143 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2144 flock() that caused the problem. */
2146 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2149 /* Test for exceeding the maximum number of tries. Either the file remains
2150 locked, or, if we haven't got it open, something is terribly wrong... */
2152 if (i >= ob->lock_retries)
2156 addr->basic_errno = ERRNO_EXISTRACE;
2157 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2158 addr->special_action = SPECIAL_FREEZE;
2162 addr->basic_errno = ERRNO_LOCKFAILED;
2163 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2169 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2171 /* Save access time (for subsequent restoration), modification time (for
2172 restoration if updating fails), size of file (for comsat and for re-setting if
2173 delivery fails in the middle - e.g. for quota exceeded). */
2175 if (fstat(fd, &statbuf) < 0)
2177 addr->basic_errno = errno;
2178 addr->message = string_sprintf("while fstatting opened mailbox %s",
2183 times.actime = statbuf.st_atime;
2184 times.modtime = statbuf.st_mtime;
2185 saved_size = statbuf.st_size;
2186 if (mailbox_size < 0) mailbox_size = saved_size;
2187 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2190 /* Prepare for writing to a new file (as opposed to appending to an old one).
2191 There are several different formats, but there is preliminary stuff concerned
2192 with quotas that applies to all of them. Finding the current size by directory
2193 scanning is expensive; for maildirs some fudges have been invented:
2195 (1) A regex can be used to extract a file size from its name;
2196 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2202 uschar *check_path = path; /* Default quota check path */
2203 const pcre *regex = NULL; /* Regex for file size from file name */
2205 if (!check_creation(string_sprintf("%s/any", path), ob->create_file))
2207 addr->basic_errno = ERRNO_BADCREATE;
2208 addr->message = string_sprintf("tried to create file in %s, but "
2209 "file creation outside the home directory is not permitted", path);
2213 #ifdef SUPPORT_MAILDIR
2214 /* For a maildir delivery, ensure that all the relevant directories exist,
2215 and a maildirfolder file if necessary. */
2217 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2218 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2220 #endif /* SUPPORT_MAILDIR */
2222 /* If we are going to do a quota check, of if maildir_use_size_file is set
2223 for a maildir delivery, compile the regular expression if there is one. We
2224 may also need to adjust the path that is used. We need to do this for
2225 maildir_use_size_file even if the quota is unset, because we still want to
2226 create the file. When maildir support is not compiled,
2227 ob->maildir_use_size_file is always FALSE. */
2229 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2231 const uschar *error;
2234 /* Compile the regex if there is one. */
2236 if (ob->quota_size_regex)
2238 if (!(regex = pcre_compile(CS ob->quota_size_regex, PCRE_COPT,
2239 CCSS &error, &offset, NULL)))
2241 addr->message = string_sprintf("appendfile: regular expression "
2242 "error: %s at offset %d while compiling %s", error, offset,
2243 ob->quota_size_regex);
2246 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2247 ob->quota_size_regex);
2250 /* Use an explicitly configured directory if set */
2252 if (ob->quota_directory)
2254 if (!(check_path = expand_string(ob->quota_directory)))
2256 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2257 "name for %s transport) failed: %s", ob->quota_directory,
2258 tblock->name, expand_string_message);
2262 if (check_path[0] != '/')
2264 addr->message = string_sprintf("appendfile: quota_directory name "
2265 "\"%s\" is not absolute", check_path);
2266 addr->basic_errno = ERRNO_NOTABSOLUTE;
2271 #ifdef SUPPORT_MAILDIR
2272 /* Otherwise, if we are handling a maildir delivery, and the directory
2273 contains a file called maildirfolder, this is a maildir++ feature telling
2274 us that this is a sub-directory of the real inbox. We should therefore do
2275 the quota check on the parent directory. Beware of the special case when
2276 the directory name itself ends in a slash. */
2278 else if (mbformat == mbf_maildir)
2280 struct stat statbuf;
2281 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2283 uschar *new_check_path = string_copy(check_path);
2284 uschar *slash = Ustrrchr(new_check_path, '/');
2290 slash = Ustrrchr(new_check_path, '/');
2295 check_path = new_check_path;
2296 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2297 "quota check directory changed to %s\n", check_path);
2302 #endif /* SUPPORT_MAILDIR */
2305 /* If we are using maildirsize files, we need to ensure that such a file
2306 exists and, if necessary, recalculate its contents. As a byproduct of this,
2307 we obtain the current size of the maildir. If no quota is to be enforced
2308 (ob->quota_value == 0), we still need the size if a threshold check will
2311 Another regular expression is used to determine which directories inside the
2312 maildir are going to be counted. */
2314 #ifdef SUPPORT_MAILDIR
2315 if (ob->maildir_use_size_file)
2317 const pcre *dir_regex = NULL;
2318 const uschar *error;
2321 if (ob->maildir_dir_regex)
2323 int check_path_len = Ustrlen(check_path);
2325 if (!(dir_regex = pcre_compile(CS ob->maildir_dir_regex, PCRE_COPT,
2326 CCSS &error, &offset, NULL)))
2328 addr->message = string_sprintf("appendfile: regular expression "
2329 "error: %s at offset %d while compiling %s", error, offset,
2330 ob->maildir_dir_regex);
2335 debug_printf("using regex for maildir directory selection: %s\n",
2336 ob->maildir_dir_regex);
2338 /* Check to see if we are delivering into an ignored directory, that is,
2339 if the delivery path starts with the quota check path, and the rest
2340 of the deliver path matches the regex; if so, set a flag to disable quota
2341 checking and maildirsize updating. */
2343 if (Ustrncmp(path, check_path, check_path_len) == 0)
2345 uschar *s = path + check_path_len;
2346 while (*s == '/') s++;
2347 s = *s ? string_sprintf("%s/new", s) : US"new";
2348 if (pcre_exec(dir_regex, NULL, CS s, Ustrlen(s), 0, 0, NULL, 0) < 0)
2350 disable_quota = TRUE;
2351 DEBUG(D_transport) debug_printf("delivery directory does not match "
2352 "maildir_quota_directory_regex: disabling quota\n");
2357 /* Quota enforcement; create and check the file. There is some discussion
2358 about whether this should happen if the quota is unset. At present, Exim
2359 always creates the file. If we ever want to change this, uncomment
2360 appropriate lines below, possibly doing a check on some option. */
2362 /* if (???? || ob->quota_value > 0) */
2369 if ((maildirsize_fd = maildir_ensure_sizefile(check_path, ob, regex, dir_regex,
2370 &size, &filecount)) == -1)
2372 addr->basic_errno = errno;
2373 addr->message = string_sprintf("while opening or reading "
2374 "%s/maildirsize", check_path);
2377 /* can also return -2, which means that the file was removed because of
2378 raciness; but in this case, the size & filecount will still have been
2381 if (mailbox_size < 0) mailbox_size = size;
2382 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2385 /* No quota enforcement; ensure file does *not* exist; calculate size if
2390 * time_t old_latest;
2391 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2392 * if (THRESHOLD_CHECK)
2393 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2394 * regex, dir_regex, FALSE);
2399 #endif /* SUPPORT_MAILDIR */
2401 /* Otherwise if we are going to do a quota check later on, and the mailbox
2402 size is not set, find the current size of the mailbox. Ditto for the file
2403 count. Note that ob->quota_filecount_value cannot be set without
2404 ob->quota_value being set. */
2407 && (ob->quota_value > 0 || THRESHOLD_CHECK)
2408 && ( mailbox_size < 0
2409 || mailbox_filecount < 0 && ob->quota_filecount_value > 0
2415 debug_printf("quota checks on directory %s\n", check_path);
2416 size = check_dir_size(check_path, &filecount, regex);
2417 if (mailbox_size < 0) mailbox_size = size;
2418 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2421 /* Handle the case of creating a unique file in a given directory (not in
2422 maildir or mailstore format - this is how smail did it). A temporary name is
2423 used to create the file. Later, when it is written, the name is changed to a
2424 unique one. There is no need to lock the file. An attempt is made to create
2425 the directory if it does not exist. */
2427 if (mbformat == mbf_smail)
2430 debug_printf("delivering to new file in %s\n", path);
2431 filename = dataname =
2432 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2433 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2434 if (fd < 0 && /* failed to open, and */
2435 (errno != ENOENT || /* either not non-exist */
2436 !ob->create_directory || /* or not allowed to make */
2437 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2438 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2440 addr->basic_errno = errno;
2441 addr->message = string_sprintf("while creating file %s", filename);
2446 #ifdef SUPPORT_MAILDIR
2448 /* Handle the case of a unique file in maildir format. The file is written to
2449 the tmp subdirectory, with a prescribed form of name. */
2451 else if (mbformat == mbf_maildir)
2454 debug_printf("delivering in maildir format in %s\n", path);
2456 nametag = ob->maildir_tag;
2458 /* Check that nametag expands successfully; a hard failure causes a panic
2459 return. The actual expansion for use happens again later, when
2460 $message_size is accurately known. */
2462 if (nametag && !expand_string(nametag) && !f.expand_string_forcedfail)
2464 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2465 "for %s transport) failed: %s", nametag, tblock->name,
2466 expand_string_message);
2470 /* We ensured the existence of all the relevant directories above. Attempt
2471 to open the temporary file a limited number of times. I think this rather
2472 scary-looking for statement is actually OK. If open succeeds, the loop is
2473 broken; if not, there is a test on the value of i. Get the time again
2474 afresh each time round the loop. Its value goes into a variable that is
2475 checked at the end, to make sure we don't release this process until the
2476 clock has ticked. */
2478 for (int i = 1;; i++)
2482 (void)gettimeofday(&msg_tv, NULL);
2483 basename = string_sprintf(TIME_T_FMT ".M%luP" PID_T_FMT ".%s",
2484 msg_tv.tv_sec, msg_tv.tv_usec, getpid(), primary_hostname);
2486 filename = dataname = string_sprintf("tmp/%s", basename);
2487 newname = string_sprintf("new/%s", basename);
2489 if (Ustat(filename, &statbuf) == 0)
2491 else if (errno == ENOENT)
2493 if ((fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode)) >= 0)
2495 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2496 filename, strerror(errno));
2499 /* Too many retries - give up */
2501 if (i >= ob->maildir_retries)
2503 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2504 filename, i, (i == 1) ? "y" : "ies");
2505 addr->basic_errno = errno;
2506 if (errno == errno_quota || errno == ENOSPC)
2507 addr->user_message = US"mailbox is full";
2511 /* Open or stat failed but we haven't tried too many times yet. */
2516 /* Note that we have to ensure the clock has ticked before leaving */
2518 wait_for_tick = TRUE;
2520 /* Why are these here? Put in because they are present in the non-maildir
2521 directory case above. */
2523 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2525 addr->basic_errno = errno;
2526 addr->message = string_sprintf("while setting perms on maildir %s",
2532 #endif /* SUPPORT_MAILDIR */
2534 #ifdef SUPPORT_MAILSTORE
2536 /* Handle the case of a unique file in mailstore format. First write the
2537 envelope to a temporary file, then open the main file. The unique base name
2538 for the files consists of the message id plus the pid of this delivery
2544 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2545 string_base62((long int)getpid()));
2548 debug_printf("delivering in mailstore format in %s\n", path);
2550 filename = string_sprintf("%s.tmp", mailstore_basename);
2551 newname = string_sprintf("%s.env", mailstore_basename);
2552 dataname = string_sprintf("%s.msg", mailstore_basename);
2554 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2555 if ( fd < 0 /* failed to open, and */
2556 && ( errno != ENOENT /* either not non-exist */
2557 || !ob->create_directory /* or not allowed to make */
2558 || !directory_make(NULL, path, ob->dirmode, FALSE) /* or failed to create dir */
2559 || (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0 /* or then failed to open */
2562 addr->basic_errno = errno;
2563 addr->message = string_sprintf("while creating file %s", filename);
2567 /* Why are these here? Put in because they are present in the non-maildir
2568 directory case above. */
2570 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2572 addr->basic_errno = errno;
2573 addr->message = string_sprintf("while setting perms on file %s",
2578 /* Built a C stream from the open file descriptor. */
2580 if (!(env_file = fdopen(fd, "wb")))
2582 addr->basic_errno = errno;
2583 addr->message = string_sprintf("fdopen of %s ("
2584 "for %s transport) failed", filename, tblock->name);
2590 /* Write the envelope file, then close it. */
2592 if (ob->mailstore_prefix)
2594 uschar *s = expand_string(ob->mailstore_prefix);
2597 if (!f.expand_string_forcedfail)
2599 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2600 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2601 tblock->name, expand_string_message);
2602 (void)fclose(env_file);
2610 fprintf(env_file, "%s", CS s);
2611 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2615 fprintf(env_file, "%s\n", sender_address);
2617 for (address_item * taddr = addr; taddr; taddr = taddr->next)
2618 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2620 if (ob->mailstore_suffix)
2622 uschar *s = expand_string(ob->mailstore_suffix);
2625 if (!f.expand_string_forcedfail)
2627 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2628 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2629 tblock->name, expand_string_message);
2630 (void)fclose(env_file);
2638 fprintf(env_file, "%s", CS s);
2639 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2643 if (fclose(env_file) != 0)
2645 addr->basic_errno = errno;
2646 addr->message = string_sprintf("while closing %s", filename);
2651 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2653 /* Now open the data file, and ensure that it has the correct ownership and
2656 if ((fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)
2658 addr->basic_errno = errno;
2659 addr->message = string_sprintf("while creating file %s", dataname);
2663 if (exim_chown(dataname, uid, gid) || Uchmod(dataname, mode))
2665 addr->basic_errno = errno;
2666 addr->message = string_sprintf("while setting perms on file %s",
2672 #endif /* SUPPORT_MAILSTORE */
2675 /* In all cases of writing to a new file, ensure that the file which is
2676 going to be renamed has the correct ownership and mode. */
2678 if (exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2680 addr->basic_errno = errno;
2681 addr->message = string_sprintf("while setting perms on file %s",
2688 /* At last we can write the message to the file, preceded by any configured
2689 prefix line, and followed by any configured suffix line. If there are any
2690 writing errors, we must defer. */
2692 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2697 /* If there is a local quota setting, check that we are not going to exceed it
2698 with this message if quota_is_inclusive is set; if it is not set, the check
2699 is for the mailbox already being over quota (i.e. the current message is not
2700 included in the check). */
2702 if (!disable_quota && ob->quota_value > 0)
2706 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2707 " this message = %d (%sincluded)\n",
2708 ob->quota_value, mailbox_size, message_size,
2709 ob->quota_is_inclusive ? "" : "not ");
2710 debug_printf(" file count quota = %d count = %d\n",
2711 ob->quota_filecount_value, mailbox_filecount);
2714 if (mailbox_size + (ob->quota_is_inclusive ? message_size:0) > ob->quota_value)
2715 if (!ob->quota_no_check)
2717 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2719 errno = ERRNO_EXIMQUOTA;
2722 DEBUG(D_transport) debug_printf("mailbox quota exceeded but ignored\n");
2724 if (ob->quota_filecount_value > 0
2725 && mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2726 ob->quota_filecount_value)
2727 if (!ob->quota_filecount_no_check)
2729 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2731 errno = ERRNO_EXIMQUOTA;
2732 filecount_msg = US" filecount";
2734 else DEBUG(D_transport) if (ob->quota_filecount_no_check)
2735 debug_printf("mailbox file count quota exceeded but ignored\n");
2741 addr->basic_errno = errno;
2742 addr->message = US"Over quota";
2743 addr->transport_return = yield;
2745 debug_printf("appendfile (verify) yields %d with errno=%d more_errno=%d\n",
2746 yield, addr->basic_errno, addr->more_errno);
2751 /* If we are writing in MBX format, what we actually do is to write the message
2752 to a temporary file, and then copy it to the real file once we know its size.
2753 This is the most straightforward way of getting the correct length in the
2754 separator line. So, what we do here is to save the real file descriptor, and
2755 replace it with one for a temporary file. The temporary file gets unlinked once
2756 opened, so that it goes away on closure. */
2759 if (yield == OK && ob->mbx_format)
2761 if (!(temp_file = tmpfile()))
2763 addr->basic_errno = errno;
2764 addr->message = US"while setting up temporary file";
2769 fd = fileno(temp_file);
2770 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2772 #endif /* SUPPORT_MBX */
2774 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2777 transport_count = 0;
2778 transport_newlines = 0;
2780 /* Write any configured prefix text first */
2782 if (yield == OK && ob->message_prefix && *ob->message_prefix)
2784 uschar *prefix = expand_string(ob->message_prefix);
2787 errno = ERRNO_EXPANDFAIL;
2788 addr->transport_return = PANIC;
2789 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2790 "transport) failed", ob->message_prefix, tblock->name);
2793 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2796 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2797 various different values for batching are handled outside; if there is more
2798 than one address available here, all must be included. If any address is a
2799 file, use its parent in the RCPT TO. */
2801 if (yield == OK && ob->use_bsmtp)
2803 transport_count = 0;
2804 transport_newlines = 0;
2805 if (ob->use_crlf) cr = US"\r";
2806 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2810 transport_newlines++;
2811 for (address_item * a = addr; a; a = a->next)
2813 address_item * b = testflag(a, af_pfr) ? a->parent : a;
2814 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2815 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2816 { yield = DEFER; break; }
2817 transport_newlines++;
2819 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2822 transport_newlines++;
2826 /* Now the message itself. The options for transport_write_message were set up
2827 at initialization time. */
2831 transport_ctx tctx = {
2835 .check_string = ob->check_string,
2836 .escape_string = ob->escape_string,
2837 .options = ob->options | topt_not_socket
2839 if (!transport_write_message(&tctx, 0))
2843 /* Now a configured suffix. */
2845 if (yield == OK && ob->message_suffix && *ob->message_suffix)
2847 uschar *suffix = expand_string(ob->message_suffix);
2850 errno = ERRNO_EXPANDFAIL;
2851 addr->transport_return = PANIC;
2852 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2853 "transport) failed", ob->message_suffix, tblock->name);
2856 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2859 /* If batch smtp, write the terminating dot. */
2861 if (yield == OK && ob->use_bsmtp)
2862 if (!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2863 else transport_newlines++;
2865 /* If MBX format is being used, all that writing was to the temporary file.
2866 However, if there was an earlier failure (Exim quota exceeded, for example),
2867 the temporary file won't have got opened - and no writing will have been done.
2868 If writing was OK, we restore the fd, and call a function that copies the
2869 message in MBX format into the real file. Otherwise use the temporary name in
2873 if (temp_file && ob->mbx_format)
2880 transport_count = 0; /* Reset transport count for actual write */
2881 /* No need to reset transport_newlines as we're just using a block copy
2882 * routine so the number won't be affected */
2883 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2885 else if (errno >= 0) dataname = US"temporary file";
2887 /* Preserve errno while closing the temporary file. */
2889 mbx_save_errno = errno;
2890 (void)fclose(temp_file);
2891 errno = mbx_save_errno;
2893 #endif /* SUPPORT_MBX */
2895 /* Force out the remaining data to check for any errors; some OS don't allow
2896 fsync() to be called for a FIFO. */
2898 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2900 /* Update message_size and message_linecount to the accurate count of bytes
2901 written, including added headers. Note; we subtract 1 from message_linecount as
2902 this variable doesn't count the new line between the header and the body of the
2905 message_size = transport_count;
2906 message_linecount = transport_newlines - 1;
2908 /* If using a maildir++ quota file, add this message's size to it, and
2909 close the file descriptor, except when the quota has been disabled because we
2910 are delivering into an uncounted folder. */
2912 #ifdef SUPPORT_MAILDIR
2915 if (yield == OK && maildirsize_fd >= 0)
2916 maildir_record_length(maildirsize_fd, message_size);
2917 maildir_save_errno = errno; /* Preserve errno while closing the file */
2918 if (maildirsize_fd >= 0)
2919 (void)close(maildirsize_fd);
2920 errno = maildir_save_errno;
2922 #endif /* SUPPORT_MAILDIR */
2924 /* If there is a quota warning threshold and we are have crossed it with this
2925 message, set the SPECIAL_WARN flag in the address, to cause a warning message
2928 if (!disable_quota && THRESHOLD_CHECK)
2930 off_t threshold = ob->quota_warn_threshold_value;
2931 if (ob->quota_warn_threshold_is_percent)
2932 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
2934 debug_printf("quota = " OFF_T_FMT
2935 " threshold = " OFF_T_FMT
2936 " old size = " OFF_T_FMT
2937 " message size = %d\n",
2938 ob->quota_value, threshold, mailbox_size,
2940 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
2941 addr->special_action = SPECIAL_WARN;
2943 /******* You might think that the test ought to be this:
2945 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
2946 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
2948 * (indeed, I was sent a patch with that in). However, it is possible to
2949 * have a warning threshold without actually imposing a quota, and I have
2950 * therefore kept Exim backwards compatible.
2955 /* Handle error while writing the file. Control should come here directly after
2956 the error, with the reason in errno. In the case of expansion failure in prefix
2957 or suffix, it will be ERRNO_EXPANDFAIL. */
2961 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
2963 /* Save the error number. If positive, it will ultimately cause a strerror()
2964 call to generate some text. */
2966 addr->basic_errno = errno;
2968 /* For system or Exim quota excession, or disk full, set more_errno to the
2969 time since the file was last read. If delivery was into a directory, the
2970 time since last read logic is not relevant, in general. However, for maildir
2971 deliveries we can approximate it by looking at the last modified time of the
2972 "new" subdirectory. Since Exim won't be adding new messages, a change to the
2973 "new" subdirectory implies that an MUA has moved a message from there to the
2976 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
2978 addr->more_errno = 0;
2979 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
2981 #ifdef SUPPORT_MAILDIR
2982 else if (mbformat == mbf_maildir)
2984 struct stat statbuf;
2985 if (Ustat("new", &statbuf) < 0)
2987 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
2988 "stat error %d for \"new\": %s\n", errno, strerror(errno));
2990 else /* Want a repeatable time when in test harness */
2991 addr->more_errno = f.running_in_test_harness ? 10 :
2992 (int)time(NULL) - statbuf.st_mtime;
2995 debug_printf("maildir: time since \"new\" directory modified = %s\n",
2996 readconf_printtime(addr->more_errno));
2998 #endif /* SUPPORT_MAILDIR */
3001 /* Handle system quota excession. Add an explanatory phrase for the error
3002 message, since some systems don't have special quota-excession errors,
3003 and on those that do, "quota" doesn't always mean anything to the user. */
3005 if (errno == errno_quota)
3008 addr->message = string_sprintf("mailbox is full "
3009 "(quota exceeded while writing to file %s)", filename);
3011 addr->message = US"mailbox is full";
3013 addr->user_message = US"mailbox is full";
3014 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3016 isdirectory ? US"" : US": time since file read = ",
3017 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3020 /* Handle Exim's own quota-imposition */
3022 else if (errno == ERRNO_EXIMQUOTA)
3024 addr->message = string_sprintf("mailbox is full "
3025 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3027 addr->user_message = US"mailbox is full";
3028 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3029 filecount_msg, dataname,
3030 isdirectory ? US"" : US": time since file read = ",
3031 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3034 /* Handle a process failure while writing via a filter; the return
3035 from child_close() is in more_errno. */
3037 else if (errno == ERRNO_FILTER_FAIL)
3040 addr->message = string_sprintf("transport filter process failed (%d) "
3041 "while writing to %s%s", addr->more_errno, dataname,
3042 (addr->more_errno == EX_EXECFAILED) ? ": unable to execute command" : "");
3045 /* Handle failure to expand header changes */
3047 else if (errno == ERRNO_CHHEADER_FAIL)
3051 string_sprintf("failed to expand headers_add or headers_remove while "
3052 "writing to %s: %s", dataname, expand_string_message);
3055 /* Handle failure to complete writing of a data block */
3057 else if (errno == ERRNO_WRITEINCOMPLETE)
3058 addr->message = string_sprintf("failed to write data block while "
3059 "writing to %s", dataname);
3061 /* Handle length mismatch on MBX copying */
3064 else if (errno == ERRNO_MBXLENGTH)
3065 addr->message = string_sprintf("length mismatch while copying MBX "
3066 "temporary file to %s", dataname);
3067 #endif /* SUPPORT_MBX */
3069 /* For other errors, a general-purpose explanation, if the message is
3072 else if (addr->message == NULL)
3073 addr->message = string_sprintf("error while writing to %s", dataname);
3075 /* For a file, reset the file size to what it was before we started, leaving
3076 the last modification time unchanged, so it will get reset also. All systems
3077 investigated so far have ftruncate(), whereas not all have the F_FREESP
3078 fcntl() call (BSDI & FreeBSD do not). */
3080 if (!isdirectory && ftruncate(fd, saved_size))
3081 DEBUG(D_transport) debug_printf("Error resetting file size\n");
3084 /* Handle successful writing - we want the modification time to be now for
3085 appended files. Remove the default backstop error number. For a directory, now
3086 is the time to rename the file with a unique name. As soon as such a name
3087 appears it may get used by another process, so we close the file first and
3088 check that all is well. */
3092 times.modtime = time(NULL);
3093 addr->basic_errno = 0;
3095 /* Handle the case of writing to a new file in a directory. This applies
3096 to all single-file formats - maildir, mailstore, and "smail format". */
3100 if (fstat(fd, &statbuf) < 0)
3102 addr->basic_errno = errno;
3103 addr->message = string_sprintf("while fstatting opened message file %s",
3108 else if (close(fd) < 0)
3110 addr->basic_errno = errno;
3111 addr->message = string_sprintf("close() error for %s",
3112 (ob->mailstore_format) ? dataname : filename);
3116 /* File is successfully written and closed. Arrange to rename it. For the
3117 different kinds of single-file delivery, some games can be played with the
3118 name. The message size is by this time set to the accurate value so that
3119 its value can be used in expansions. */
3123 uschar *renamename = newname;
3126 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3128 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3129 situation. The name is built by expanding the directory_file option, and
3130 we make the inode number available for use in this. The expansion was
3131 checked for syntactic validity above, before we wrote the file.
3133 We have to be careful here, in case the file name exists. (In the other
3134 cases, the names used are constructed to be unique.) The rename()
3135 function just replaces an existing file - we don't want that! So instead
3136 of calling rename(), we must use link() and unlink().
3138 In this case, if the link fails because of an existing file, we wait
3139 for one second and try the expansion again, to see if it produces a
3140 different value. Do this up to 5 times unless the name stops changing.
3141 This makes it possible to build values that are based on the time, and
3142 still cope with races from multiple simultaneous deliveries. */
3147 uschar *old_renameleaf = US"";
3149 for (int i = 0; ; sleep(1), i++)
3151 deliver_inode = statbuf.st_ino;
3152 renameleaf = expand_string(ob->dirfilename);
3157 addr->transport_return = PANIC;
3158 addr->message = string_sprintf("Expansion of \"%s\" "
3159 "(directory_file for %s transport) failed: %s",
3160 ob->dirfilename, tblock->name, expand_string_message);
3164 renamename = string_sprintf("%s/%s", path, renameleaf);
3165 if (Ulink(filename, renamename) < 0)
3167 DEBUG(D_transport) debug_printf("link failed: %s\n",
3169 if (errno != EEXIST || i >= 4 ||
3170 Ustrcmp(renameleaf, old_renameleaf) == 0)
3172 addr->basic_errno = errno;
3173 addr->message = string_sprintf("while renaming %s as %s",
3174 filename, renamename);
3178 old_renameleaf = renameleaf;
3179 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3188 } /* re-expand loop */
3189 } /* not mailstore or maildir */
3191 /* For maildir and mailstore formats, the new name was created earlier,
3192 except that for maildir, there is the possibility of adding a "tag" on
3193 the end of the name by expanding the value of nametag. This usually
3194 includes a reference to the message size. The expansion of nametag was
3195 checked above, before the file was opened. It either succeeded, or
3196 provoked a soft failure. So any failure here can be treated as soft.
3197 Ignore non-printing characters and / and put a colon at the start if the
3198 first character is alphanumeric. */
3204 uschar *iptr = expand_string(nametag);
3207 uschar *etag = store_get(Ustrlen(iptr) + 2, is_tainted(iptr));
3208 uschar *optr = etag;
3209 for ( ; *iptr; iptr++)
3210 if (mac_isgraph(*iptr) && *iptr != '/')
3212 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3216 renamename = string_sprintf("%s%s", newname, etag);
3220 /* Do the rename. If the name is too long and a tag exists, try again
3223 if (Urename(filename, renamename) < 0 &&
3224 (nametag == NULL || errno != ENAMETOOLONG ||
3225 (renamename = newname, Urename(filename, renamename) < 0)))
3227 addr->basic_errno = errno;
3228 addr->message = string_sprintf("while renaming %s as %s",
3229 filename, renamename);
3233 /* Rename succeeded */
3237 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3239 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3241 } /* maildir or mailstore */
3242 } /* successful write + close */
3244 } /* write success */
3247 /* For a file, restore the last access time (atime), and set the modification
3248 time as required - changed if write succeeded, unchanged if not. */
3250 if (!isdirectory) utime(CS filename, ×);
3252 /* Notify comsat if configured to do so. It only makes sense if the configured
3253 file is the one that the comsat daemon knows about. */
3255 if (ob->notify_comsat && yield == OK && deliver_localpart)
3256 notify_comsat(deliver_localpart, saved_size);
3258 /* Pass back the final return code in the address structure */
3261 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3262 yield, addr->basic_errno, addr->more_errno);
3264 addr->transport_return = yield;
3266 /* Close the file, which will release the fcntl lock. For a directory write it
3267 is closed above, except in cases of error which goto RETURN, when we also need
3268 to remove the original file(s). For MBX locking, if all has gone well, before
3269 closing the file, see if we can get an exclusive lock on it, in which case we
3270 can unlink the /tmp lock file before closing it. This is always a non-blocking
3271 lock; there's no need to wait if we can't get it. If everything has gone right
3272 but close fails, defer the message. Then unlink the lock file, if present. This
3273 point in the code is jumped to from a number of places when errors are
3274 detected, in order to get the file closed and the lock file tidied away. */
3279 if (mbx_lockfd >= 0)
3281 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3282 ob->use_flock, 0) >= 0)
3285 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3286 Uunlink(mbx_lockname);
3288 (void)close(mbx_lockfd);
3290 #endif /* SUPPORT_MBX */
3292 if (fd >= 0 && close(fd) < 0 && yield == OK)
3294 addr->basic_errno = errno;
3295 addr->message = string_sprintf("while closing %s", filename);
3296 addr->transport_return = DEFER;
3299 if (hd >= 0) Uunlink(lockname);
3301 /* We get here with isdirectory and filename set only in error situations. */
3303 if (isdirectory && filename)
3306 if (dataname != filename) Uunlink(dataname);
3309 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3310 file name relies on time + pid. We must not allow the process to finish until
3311 the clock has move on by at least one microsecond. Usually we expect this
3312 already to be the case, but machines keep getting faster... */
3314 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3316 /* A return of FALSE means that if there was an error, a common error was
3317 put in the first address of a batch. */
3322 addr->transport_return = PANIC;
3326 #endif /*!MACRO_PREDEF*/
3327 /* End of transport/appendfile.c */