1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* See the file NOTICE for conditions of use and distribution. */
10 #include "appendfile.h"
12 #ifdef SUPPORT_MAILDIR
13 #include "tf_maildir.h"
17 /* Options specific to the appendfile transport. They must be in alphabetic
18 order (note that "_" comes before the lower case letters). Some of them are
19 stored in the publicly visible instance block - these are flagged with the
22 optionlist appendfile_transport_options[] = {
23 #ifdef SUPPORT_MAILDIR
24 { "*expand_maildir_use_size_file", opt_stringptr,
25 (void *)offsetof(appendfile_transport_options_block, expand_maildir_use_size_file) },
27 { "*set_use_fcntl_lock",opt_bool | opt_hidden,
28 (void *)offsetof(appendfile_transport_options_block, set_use_fcntl) },
29 { "*set_use_flock_lock",opt_bool | opt_hidden,
30 (void *)offsetof(appendfile_transport_options_block, set_use_flock) },
31 { "*set_use_lockfile", opt_bool | opt_hidden,
32 (void *)offsetof(appendfile_transport_options_block, set_use_lockfile) },
34 { "*set_use_mbx_lock", opt_bool | opt_hidden,
35 (void *)offsetof(appendfile_transport_options_block, set_use_mbx_lock) },
37 { "allow_fifo", opt_bool,
38 (void *)offsetof(appendfile_transport_options_block, allow_fifo) },
39 { "allow_symlink", opt_bool,
40 (void *)offsetof(appendfile_transport_options_block, allow_symlink) },
41 { "batch_id", opt_stringptr | opt_public,
42 (void *)offsetof(transport_instance, batch_id) },
43 { "batch_max", opt_int | opt_public,
44 (void *)offsetof(transport_instance, batch_max) },
45 { "check_group", opt_bool,
46 (void *)offsetof(appendfile_transport_options_block, check_group) },
47 { "check_owner", opt_bool,
48 (void *)offsetof(appendfile_transport_options_block, check_owner) },
49 { "check_string", opt_stringptr,
50 (void *)offsetof(appendfile_transport_options_block, check_string) },
51 { "create_directory", opt_bool,
52 (void *)offsetof(appendfile_transport_options_block, create_directory) },
53 { "create_file", opt_stringptr,
54 (void *)offsetof(appendfile_transport_options_block, create_file_string) },
55 { "directory", opt_stringptr,
56 (void *)offsetof(appendfile_transport_options_block, dirname) },
57 { "directory_file", opt_stringptr,
58 (void *)offsetof(appendfile_transport_options_block, dirfilename) },
59 { "directory_mode", opt_octint,
60 (void *)offsetof(appendfile_transport_options_block, dirmode) },
61 { "escape_string", opt_stringptr,
62 (void *)offsetof(appendfile_transport_options_block, escape_string) },
63 { "file", opt_stringptr,
64 (void *)offsetof(appendfile_transport_options_block, filename) },
65 { "file_format", opt_stringptr,
66 (void *)offsetof(appendfile_transport_options_block, file_format) },
67 { "file_must_exist", opt_bool,
68 (void *)offsetof(appendfile_transport_options_block, file_must_exist) },
69 { "lock_fcntl_timeout", opt_time,
70 (void *)offsetof(appendfile_transport_options_block, lock_fcntl_timeout) },
71 { "lock_flock_timeout", opt_time,
72 (void *)offsetof(appendfile_transport_options_block, lock_flock_timeout) },
73 { "lock_interval", opt_time,
74 (void *)offsetof(appendfile_transport_options_block, lock_interval) },
75 { "lock_retries", opt_int,
76 (void *)offsetof(appendfile_transport_options_block, lock_retries) },
77 { "lockfile_mode", opt_octint,
78 (void *)offsetof(appendfile_transport_options_block, lockfile_mode) },
79 { "lockfile_timeout", opt_time,
80 (void *)offsetof(appendfile_transport_options_block, lockfile_timeout) },
81 { "mailbox_filecount", opt_stringptr,
82 (void *)offsetof(appendfile_transport_options_block, mailbox_filecount_string) },
83 { "mailbox_size", opt_stringptr,
84 (void *)offsetof(appendfile_transport_options_block, mailbox_size_string) },
85 #ifdef SUPPORT_MAILDIR
86 { "maildir_format", opt_bool,
87 (void *)offsetof(appendfile_transport_options_block, maildir_format ) } ,
88 { "maildir_quota_directory_regex", opt_stringptr,
89 (void *)offsetof(appendfile_transport_options_block, maildir_dir_regex) },
90 { "maildir_retries", opt_int,
91 (void *)offsetof(appendfile_transport_options_block, maildir_retries) },
92 { "maildir_tag", opt_stringptr,
93 (void *)offsetof(appendfile_transport_options_block, maildir_tag) },
94 { "maildir_use_size_file", opt_expand_bool,
95 (void *)offsetof(appendfile_transport_options_block, maildir_use_size_file ) } ,
96 { "maildirfolder_create_regex", opt_stringptr,
97 (void *)offsetof(appendfile_transport_options_block, maildirfolder_create_regex ) },
98 #endif /* SUPPORT_MAILDIR */
99 #ifdef SUPPORT_MAILSTORE
100 { "mailstore_format", opt_bool,
101 (void *)offsetof(appendfile_transport_options_block, mailstore_format ) },
102 { "mailstore_prefix", opt_stringptr,
103 (void *)offsetof(appendfile_transport_options_block, mailstore_prefix ) },
104 { "mailstore_suffix", opt_stringptr,
105 (void *)offsetof(appendfile_transport_options_block, mailstore_suffix ) },
106 #endif /* SUPPORT_MAILSTORE */
108 { "mbx_format", opt_bool,
109 (void *)offsetof(appendfile_transport_options_block, mbx_format ) } ,
110 #endif /* SUPPORT_MBX */
111 { "message_prefix", opt_stringptr,
112 (void *)offsetof(appendfile_transport_options_block, message_prefix) },
113 { "message_suffix", opt_stringptr,
114 (void *)offsetof(appendfile_transport_options_block, message_suffix) },
115 { "mode", opt_octint,
116 (void *)offsetof(appendfile_transport_options_block, mode) },
117 { "mode_fail_narrower",opt_bool,
118 (void *)offsetof(appendfile_transport_options_block, mode_fail_narrower) },
119 { "notify_comsat", opt_bool,
120 (void *)offsetof(appendfile_transport_options_block, notify_comsat) },
121 { "quota", opt_stringptr,
122 (void *)offsetof(appendfile_transport_options_block, quota) },
123 { "quota_directory", opt_stringptr,
124 (void *)offsetof(appendfile_transport_options_block, quota_directory) },
125 { "quota_filecount", opt_stringptr,
126 (void *)offsetof(appendfile_transport_options_block, quota_filecount) },
127 { "quota_is_inclusive", opt_bool,
128 (void *)offsetof(appendfile_transport_options_block, quota_is_inclusive) },
129 { "quota_size_regex", opt_stringptr,
130 (void *)offsetof(appendfile_transport_options_block, quota_size_regex) },
131 { "quota_warn_message", opt_stringptr | opt_public,
132 (void *)offsetof(transport_instance, warn_message) },
133 { "quota_warn_threshold", opt_stringptr,
134 (void *)offsetof(appendfile_transport_options_block, quota_warn_threshold) },
135 { "use_bsmtp", opt_bool,
136 (void *)offsetof(appendfile_transport_options_block, use_bsmtp) },
137 { "use_crlf", opt_bool,
138 (void *)offsetof(appendfile_transport_options_block, use_crlf) },
139 { "use_fcntl_lock", opt_bool_set,
140 (void *)offsetof(appendfile_transport_options_block, use_fcntl) },
141 { "use_flock_lock", opt_bool_set,
142 (void *)offsetof(appendfile_transport_options_block, use_flock) },
143 { "use_lockfile", opt_bool_set,
144 (void *)offsetof(appendfile_transport_options_block, use_lockfile) },
146 { "use_mbx_lock", opt_bool_set,
147 (void *)offsetof(appendfile_transport_options_block, use_mbx_lock) },
148 #endif /* SUPPORT_MBX */
151 /* Size of the options list. An extern variable has to be used so that its
152 address can appear in the tables drtables.c. */
154 int appendfile_transport_options_count =
155 sizeof(appendfile_transport_options)/sizeof(optionlist);
161 appendfile_transport_options_block appendfile_transport_option_defaults = {0};
162 void appendfile_transport_init(transport_instance *tblock) {}
163 BOOL appendfile_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
165 #else /*!MACRO_PREDEF*/
167 /* Default private options block for the appendfile transport. */
169 appendfile_transport_options_block appendfile_transport_option_defaults = {
172 US"q${base62:$tod_epoch}-$inode", /* dirfilename */
173 NULL, /* message_prefix (default reset in init if not bsmtp) */
174 NULL, /* message_suffix (ditto) */
175 US"anywhere", /* create_file_string (string value for create_file) */
177 NULL, /* quota_directory */
178 NULL, /* quota_filecount */
179 NULL, /* quota_size_regex */
180 NULL, /* quota_warn_threshold */
181 NULL, /* mailbox_size_string */
182 NULL, /* mailbox_filecount_string */
183 NULL, /* expand_maildir_use_size_file */
184 US"^(?:cur|new|\\..*)$", /* maildir_dir_regex */
185 NULL, /* maildir_tag */
186 NULL, /* maildirfolder_create_regex */
187 NULL, /* mailstore_prefix */
188 NULL, /* mailstore_suffix */
189 NULL, /* check_string (default changed for non-bsmtp file)*/
190 NULL, /* escape_string (ditto) */
191 NULL, /* file_format */
193 0, /* quota_warn_threshold_value */
194 -1, /* mailbox_size_value */
195 -1, /* mailbox_filecount_value */
196 0, /* quota_filecount_value */
197 APPENDFILE_MODE, /* mode */
198 APPENDFILE_DIRECTORY_MODE, /* dirmode */
199 APPENDFILE_LOCKFILE_MODE, /* lockfile_mode */
200 30*60, /* lockfile_timeout */
201 0, /* lock_fcntl_timeout */
202 0, /* lock_flock_timeout */
203 10, /* lock_retries */
204 3, /* lock_interval */
205 10, /* maildir_retries */
206 create_anywhere,/* create_file */
208 FALSE, /* allow_fifo */
209 FALSE, /* allow_symlink */
210 FALSE, /* check_group */
211 TRUE, /* check_owner */
212 TRUE, /* create_directory */
213 FALSE, /* notify_comsat */
214 TRUE, /* use_lockfile */
215 FALSE, /* set_use_lockfile */
216 TRUE, /* use_fcntl */
217 FALSE, /* set_use_fcntl */
218 FALSE, /* use_flock */
219 FALSE, /* set_use_flock */
220 FALSE, /* use_mbx_lock */
221 FALSE, /* set_use_mbx_lock */
222 FALSE, /* use_bsmtp */
223 FALSE, /* use_crlf */
224 FALSE, /* file_must_exist */
225 TRUE, /* mode_fail_narrower */
226 FALSE, /* maildir_format */
227 FALSE, /* maildir_use_size_file */
228 FALSE, /* mailstore_format */
229 FALSE, /* mbx_format */
230 FALSE, /* quota_warn_threshold_is_percent */
231 TRUE, /* quota_is_inclusive */
232 FALSE, /* quota_no_check */
233 FALSE /* quota_filecount_no_check */
237 /* Encodings for mailbox formats, and their names. MBX format is actually
238 supported only if SUPPORT_MBX is set. */
240 enum { mbf_unix, mbf_mbx, mbf_smail, mbf_maildir, mbf_mailstore };
242 static const char *mailbox_formats[] = {
243 "unix", "mbx", "smail", "maildir", "mailstore" };
246 /* Check warn threshold only if quota size set or not a percentage threshold
247 percentage check should only be done if quota > 0 */
249 #define THRESHOLD_CHECK (ob->quota_warn_threshold_value > 0 && \
250 (!ob->quota_warn_threshold_is_percent || ob->quota_value > 0))
254 /*************************************************
255 * Setup entry point *
256 *************************************************/
258 /* Called for each delivery in the privileged state, just before the uid/gid
259 are changed and the main entry point is called. We use this function to
260 expand any quota settings, so that it can access files that may not be readable
261 by the user. It is also used to pick up external mailbox size information, if
265 tblock points to the transport instance
266 addrlist addresses about to be delivered (not used)
267 dummy not used (doesn't pass back data)
268 uid the uid that will be set (not used)
269 gid the gid that will be set (not used)
270 errmsg where to put an error message
272 Returns: OK, FAIL, or DEFER
276 appendfile_transport_setup(transport_instance *tblock, address_item *addrlist,
277 transport_feedback *dummy, uid_t uid, gid_t gid, uschar **errmsg)
279 appendfile_transport_options_block *ob =
280 (appendfile_transport_options_block *)(tblock->options_block);
281 uschar *q = ob->quota;
282 double default_value = 0.0;
284 addrlist = addrlist; /* Keep picky compilers happy */
289 if (ob->expand_maildir_use_size_file)
290 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
291 US"`maildir_use_size_file` in transport", tblock->name);
293 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
296 for (int i = 0; i < 5; i++)
300 uschar *which = NULL;
302 if (q == NULL) d = default_value;
306 uschar *s = expand_string(q);
310 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
311 "%s", q, tblock->name, expand_string_message);
312 return f.search_find_defer ? DEFER : FAIL;
315 d = Ustrtod(s, &rest);
317 /* Handle following characters K, M, G, %, the latter being permitted
318 for quota_warn_threshold only. A threshold with no quota setting is
321 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
322 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
323 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
324 else if (*rest == '%' && i == 2)
326 if (ob->quota_value <= 0 && !ob->maildir_use_size_file)
328 else if ((int)d < 0 || (int)d > 100)
330 *errmsg = string_sprintf("Invalid quota_warn_threshold percentage (%d)"
331 " for %s transport", (int)d, tblock->name);
334 ob->quota_warn_threshold_is_percent = TRUE;
339 /* For quota and quota_filecount there may be options
340 appended. Currently only "no_check", so we can be lazy parsing it */
341 if (i < 2 && Ustrstr(rest, "/no_check") == rest)
344 rest += sizeof("/no_check") - 1;
347 while (isspace(*rest)) rest++;
351 *errmsg = string_sprintf("Malformed value \"%s\" (expansion of \"%s\") "
352 "in %s transport", s, q, tblock->name);
357 /* Set each value, checking for possible overflow. */
362 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
364 ob->quota_value = (off_t)d;
365 ob->quota_no_check = no_check;
366 q = ob->quota_filecount;
370 if (d >= 2.0*1024.0*1024.0*1024.0)
371 which = US"quota_filecount";
372 ob->quota_filecount_value = (int)d;
373 ob->quota_filecount_no_check = no_check;
374 q = ob->quota_warn_threshold;
378 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
379 which = US"quota_warn_threshold";
380 ob->quota_warn_threshold_value = (off_t)d;
381 q = ob->mailbox_size_string;
382 default_value = -1.0;
386 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
387 which = US"mailbox_size";;
388 ob->mailbox_size_value = (off_t)d;
389 q = ob->mailbox_filecount_string;
393 if (d >= 2.0*1024.0*1024.0*1024.0)
394 which = US"mailbox_filecount";
395 ob->mailbox_filecount_value = (int)d;
401 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
402 "%s transport", which, d, tblock->name);
412 /*************************************************
413 * Initialization entry point *
414 *************************************************/
416 /* Called for each instance, after its options have been read, to
417 enable consistency checks to be done, or anything else that needs
421 appendfile_transport_init(transport_instance *tblock)
423 appendfile_transport_options_block *ob =
424 (appendfile_transport_options_block *)(tblock->options_block);
426 /* Set up the setup entry point, to be called in the privileged state */
428 tblock->setup = appendfile_transport_setup;
430 /* Lock_retries must be greater than zero */
432 if (ob->lock_retries == 0) ob->lock_retries = 1;
434 /* Only one of a file name or directory name must be given. */
436 if (ob->filename != NULL && ob->dirname != NULL)
437 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
438 "only one of \"file\" or \"directory\" can be specified", tblock->name);
440 /* If a file name was specified, neither quota_filecount nor quota_directory
443 if (ob->filename != NULL)
445 if (ob->quota_filecount != NULL)
446 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
447 "quota_filecount must not be set without \"directory\"", tblock->name);
448 if (ob->quota_directory != NULL)
449 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
450 "quota_directory must not be set without \"directory\"", tblock->name);
453 /* The default locking depends on whether MBX is set or not. Change the
454 built-in default if none of the lock options has been explicitly set. At least
455 one form of locking is required in all cases, but mbx locking changes the
456 meaning of fcntl and flock locking. */
458 /* Not all operating systems provide flock(). For those that do, if flock is
459 requested, the default for fcntl is FALSE. */
464 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
465 "flock() support was not available in the operating system when this "
466 "binary was built", tblock->name);
467 #endif /* NO_FLOCK */
468 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
474 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
475 !ob->set_use_mbx_lock)
477 ob->use_lockfile = ob->use_flock = FALSE;
478 ob->use_mbx_lock = ob->use_fcntl = TRUE;
480 else if (ob->use_mbx_lock)
482 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
483 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
484 if (!ob->set_use_flock) ob->use_flock = FALSE;
485 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
488 #endif /* SUPPORT_MBX */
490 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
491 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
492 "no locking configured", tblock->name);
494 /* Unset timeouts for non-used locking types */
496 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
497 if (!ob->use_flock) ob->lock_flock_timeout = 0;
499 /* If a directory name was specified, only one of maildir or mailstore may be
500 specified, and if quota_filecount or quota_directory is given, quota must
503 if (ob->dirname != NULL)
505 if (ob->maildir_format && ob->mailstore_format)
506 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
507 "only one of maildir and mailstore may be specified", tblock->name);
508 if (ob->quota_filecount != NULL && ob->quota == NULL)
509 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
510 "quota must be set if quota_filecount is set", tblock->name);
511 if (ob->quota_directory != NULL && ob->quota == NULL)
512 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
513 "quota must be set if quota_directory is set", tblock->name);
516 /* If a fixed uid field is set, then a gid field must also be set. */
518 if (tblock->uid_set && !tblock->gid_set && tblock->expand_gid == NULL)
519 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
520 "user set without group for the %s transport", tblock->name);
522 /* If "create_file" is set, check that a valid option is given, and set the
525 if (ob->create_file_string != NULL)
528 if (Ustrcmp(ob->create_file_string, "anywhere") == 0) value = create_anywhere;
529 else if (Ustrcmp(ob->create_file_string, "belowhome") == 0) value =
531 else if (Ustrcmp(ob->create_file_string, "inhome") == 0)
532 value = create_inhome;
534 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
535 "invalid value given for \"file_create\" for the %s transport: %s",
536 tblock->name, ob->create_file_string);
537 ob->create_file = value;
540 /* If quota_warn_threshold is set, set up default for warn_message. It may
541 not be used if the actual threshold for a given delivery ends up as zero,
542 of if it's given as a percentage and there's no quota setting. */
544 if (ob->quota_warn_threshold != NULL)
546 if (tblock->warn_message == NULL) tblock->warn_message = US
547 "To: $local_part@$domain\n"
548 "Subject: Your mailbox\n\n"
549 "This message is automatically created by mail delivery software (Exim).\n\n"
550 "The size of your mailbox has exceeded a warning threshold that is\n"
551 "set by the system administrator.\n";
554 /* If batch SMTP is set, force the check and escape strings, and arrange that
555 headers are also escaped. */
559 ob->check_string = US".";
560 ob->escape_string = US"..";
561 ob->options |= topt_escape_headers;
564 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
565 insert default values for for the affixes and the check/escape strings. */
567 else if (ob->dirname == NULL && !ob->maildir_format && !ob->mailstore_format)
569 if (ob->message_prefix == NULL) ob->message_prefix =
570 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
571 if (ob->message_suffix == NULL) ob->message_suffix = US"\n";
572 if (ob->check_string == NULL) ob->check_string = US"From ";
573 if (ob->escape_string == NULL) ob->escape_string = US">From ";
577 /* Set up the bitwise options for transport_write_message from the various
578 driver options. Only one of body_only and headers_only can be set. */
581 (tblock->body_only ? topt_no_headers : 0) |
582 (tblock->headers_only ? topt_no_body : 0) |
583 (tblock->return_path_add ? topt_add_return_path : 0) |
584 (tblock->delivery_date_add ? topt_add_delivery_date : 0) |
585 (tblock->envelope_to_add ? topt_add_envelope_to : 0) |
586 ((ob->use_crlf || ob->mbx_format) ? topt_use_crlf : 0);
591 /*************************************************
593 *************************************************/
595 /* The comsat daemon is the thing that provides asynchronous notification of
596 the arrival of local messages, if requested by the user by "biff y". It is a
597 BSD thing that uses a TCP/IP protocol for communication. A message consisting
598 of the text "user@offset" must be sent, where offset is the place in the
599 mailbox where new mail starts. There is no scope for telling it which file to
600 look at, which makes it a less than useful if mail is being delivered into a
601 non-standard place such as the user's home directory. In fact, it doesn't seem
602 to pay much attention to the offset.
606 offset offset in mailbox
612 notify_comsat(uschar *user, off_t offset)
618 DEBUG(D_transport) debug_printf("notify_comsat called\n");
620 sprintf(CS buffer, "%.200s@" OFF_T_FMT "\n", user, offset);
622 if ((sp = getservbyname("biff", "udp")) == NULL)
624 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
628 host.name = US"localhost";
632 /* This code is all set up to look up "localhost" and use all its addresses
633 until one succeeds. However, it appears that at least on some systems, comsat
634 doesn't listen on the ::1 address. So for the moment, just force the address to
635 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
636 can be changed. (But actually, comsat is probably dying out anyway.) */
639 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
641 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
646 host.address = US"127.0.0.1";
649 for (host_item * h = &host; h; h = h->next)
652 int host_af = Ustrchr(h->address, ':') != NULL ? AF_INET6 : AF_INET;
654 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
656 if ((sock = ip_socket(SOCK_DGRAM, host_af)) < 0) continue;
658 /* Connect never fails for a UDP socket, so don't set a timeout. */
660 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0, NULL);
661 rc = send(sock, buffer, Ustrlen(buffer) + 1, 0);
666 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
673 /*************************************************
674 * Check the format of a file *
675 *************************************************/
677 /* This function is called when file_format is set, to check that an existing
678 file has the right format. The format string contains text/transport pairs. The
679 string matching is literal. we just read big_buffer_size bytes, because this is
680 all about the first few bytes of a file.
684 tblock the transport block
685 addr the address block - for inserting error data
687 Returns: pointer to the required transport, or NULL
691 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
693 const uschar *format =
694 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
696 int len = read(cfd, data, sizeof(data));
700 DEBUG(D_transport) debug_printf("checking file format\n");
702 /* An empty file matches the current transport */
704 if (len == 0) return tblock;
706 /* Search the formats for a match */
708 while ((s = string_nextinlist(&format,&sep,big_buffer,big_buffer_size)))
710 int slen = Ustrlen(s);
711 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
712 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
716 for (transport_instance * tt = transports; tt; tt = tt->next)
717 if (Ustrcmp(tp, tt->name) == 0)
720 debug_printf("file format -> %s transport\n", tt->name);
723 addr->basic_errno = ERRNO_BADTRANSPORT;
724 addr->message = string_sprintf("%s transport (for %.*s format) not found",
730 /* Failed to find a match */
732 addr->basic_errno = ERRNO_FORMATUNKNOWN;
733 addr->message = US"mailbox file format unrecognized";
740 /*************************************************
741 * Check directory's files for quota *
742 *************************************************/
744 /* This function is called if quota is set for one of the delivery modes that
745 delivers into a specific directory. It scans the directory and stats all the
746 files in order to get a total size and count. This is an expensive thing to do,
747 but some people are prepared to bear the cost. Alternatively, if size_regex is
748 set, it is used as a regex to try to extract the size from the file name, a
749 strategy that some people use on maildir files on systems where the users have
752 The function is global, because it is also called from tf_maildir.c for maildir
753 folders (which should contain only regular files).
755 Note: Any problems can be written to debugging output, but cannot be written to
756 the log, because we are running as an unprivileged user here.
759 dirname the name of the directory
760 countptr where to add the file count (because this function recurses)
761 regex a compiled regex to get the size from a name
763 Returns: the sum of the sizes of the stattable files
764 zero if the directory cannot be opened
768 check_dir_size(uschar *dirname, int *countptr, const pcre *regex)
772 int count = *countptr;
776 dir = opendir(CS dirname);
777 if (dir == NULL) return 0;
779 while ((ent = readdir(dir)) != NULL)
781 uschar *name = US ent->d_name;
784 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
788 /* If there's a regex, try to find the size using it */
793 if (pcre_exec(regex, NULL, CS name, Ustrlen(name), 0, 0, ovector,6) >= 2)
796 off_t size = (off_t)Ustrtod(name + ovector[2], &endptr);
797 if (endptr == name + ovector[3])
801 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
807 debug_printf("check_dir_size: regex did not match %s\n", name);
810 /* No regex or no match for the regex, or captured non-digits */
812 if (!string_format(buffer, sizeof(buffer), "%s/%s", dirname, name))
815 debug_printf("check_dir_size: name too long: dir=%s name=%s\n", dirname,
820 if (Ustat(buffer, &statbuf) < 0)
823 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, buffer,
828 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
829 sum += statbuf.st_size;
830 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
831 sum += check_dir_size(buffer, &count, regex);
836 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
846 /*************************************************
847 * Apply a lock to a file descriptor *
848 *************************************************/
850 /* This function applies a lock to a file descriptor, using a blocking or
851 non-blocking lock, depending on the timeout value. It can apply either or
852 both of a fcntl() and a flock() lock. However, not all OS support flock();
853 for those that don't, the use_flock option cannot be set.
856 fd the file descriptor
857 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
858 fcntl() format); the flock() type is deduced if needed
859 dofcntl do fcntl() locking
860 fcntltime non-zero to use blocking fcntl()
861 doflock do flock() locking
862 flocktime non-zero to use blocking flock()
864 Returns: yield of the fcntl() or flock() call, with errno preserved;
865 sigalrm_seen set if there has been a timeout
869 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
874 struct flock lock_data;
875 lock_data.l_type = fcntltype;
876 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
878 sigalrm_seen = FALSE;
885 yield = fcntl(fd, F_SETLKW, &lock_data);
890 else yield = fcntl(fd, F_SETLK, &lock_data);
894 if (doflock && (yield >= 0))
896 int flocktype = (fcntltype == F_WRLCK) ? LOCK_EX : LOCK_SH;
900 yield = flock(fd, flocktype);
905 else yield = flock(fd, flocktype | LOCK_NB);
907 #endif /* NO_FLOCK */
916 /*************************************************
917 * Copy message into MBX mailbox *
918 *************************************************/
920 /* This function is called when a message intended for a MBX mailbox has been
921 written to a temporary file. We can now get the size of the message and then
922 copy it in MBX format to the mailbox.
925 to_fd fd to write to (the real mailbox)
926 from_fd fd to read from (the temporary file)
927 saved_size current size of mailbox
929 Returns: OK if all went well, DEFER otherwise, with errno preserved
930 the number of bytes written are added to transport_count
931 by virtue of calling transport_write_block()
934 /* Values taken from c-client */
936 #define MBX_HDRSIZE 2048
937 #define MBX_NUSERFLAGS 30
940 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
945 transport_ctx tctx = { .u={.fd = to_fd}, .options = topt_not_socket };
947 /* If the current mailbox size is zero, write a header block */
952 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
953 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
954 (long int)time(NULL));
955 for (int i = 0; i < MBX_NUSERFLAGS; i++)
956 sprintf (CS(s += Ustrlen(s)), "\015\012");
957 if (!transport_write_block (&tctx, deliver_out_buffer, MBX_HDRSIZE, FALSE))
961 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
963 /* Now construct the message's header from the time and the RFC822 file
964 size, including CRLFs, which is the size of the input (temporary) file. */
966 if (fstat(from_fd, &statbuf) < 0) return DEFER;
967 size = statbuf.st_size;
969 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
970 tod_stamp(tod_mbx), size, 0L, 0, 0);
971 used = Ustrlen(deliver_out_buffer);
973 /* Rewind the temporary file, and copy it over in chunks. */
975 if (lseek(from_fd, 0 , SEEK_SET) < 0) return DEFER;
979 int len = read(from_fd, deliver_out_buffer + used,
980 DELIVER_OUT_BUFFER_SIZE - used);
983 if (len == 0) errno = ERRNO_MBXLENGTH;
986 if (!transport_write_block(&tctx, deliver_out_buffer, used + len, FALSE))
994 #endif /* SUPPORT_MBX */
998 /*************************************************
999 * Check creation is permitted *
1000 *************************************************/
1002 /* This function checks whether a given file name is permitted to be created,
1003 as controlled by the create_file option. If no home directory is set, however,
1004 we can't do any tests.
1007 filename the file name
1008 create_file the ob->create_file option
1010 Returns: TRUE if creation is permitted
1014 check_creation(uschar *filename, int create_file)
1018 if (deliver_home != NULL && create_file != create_anywhere)
1020 int len = Ustrlen(deliver_home);
1021 uschar *file = filename;
1023 while (file[0] == '/' && file[1] == '/') file++;
1024 if (Ustrncmp(file, deliver_home, len) != 0 || file[len] != '/' ||
1025 ( Ustrchr(file+len+2, '/') != NULL &&
1027 create_file != create_belowhome ||
1028 Ustrstr(file+len, "/../") != NULL
1033 /* If yield is TRUE, the file name starts with the home directory, and does
1034 not contain any instances of "/../" in the "belowhome" case. However, it may
1035 still contain symbolic links. We can check for this by making use of
1036 realpath(), which most Unixes seem to have (but make it possible to cut this
1037 out). We can't just use realpath() on the whole file name, because we know
1038 the file itself doesn't exist, and intermediate directories may also not
1039 exist. What we want to know is the real path of the longest existing part of
1040 the path. That must match the home directory's beginning, whichever is the
1044 if (yield && create_file == create_belowhome)
1048 for (uschar * slash = Ustrrchr(file, '/'); /* There is known to be one */
1049 rp == NULL && slash > file; /* Stop if reached beginning */
1053 rp = US realpath(CS file, CS big_buffer);
1054 next = Ustrrchr(file, '/');
1058 /* If rp == NULL it means that none of the relevant directories exist.
1059 This is not a problem here - it means that no symbolic links can exist,
1060 which is all we are worried about. Otherwise, we must compare it
1061 against the start of the home directory. However, that may itself
1062 contain symbolic links, so we have to "realpath" it as well, if
1067 uschar hdbuffer[PATH_MAX+1];
1068 uschar *rph = deliver_home;
1069 int rlen = Ustrlen(big_buffer);
1071 rp = US realpath(CS deliver_home, CS hdbuffer);
1078 if (rlen > len) rlen = len;
1079 if (Ustrncmp(rph, big_buffer, rlen) != 0)
1082 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
1083 big_buffer, deliver_home);
1087 #endif /* NO_REALPATH */
1095 /*************************************************
1096 * Main entry point *
1097 *************************************************/
1099 /* See local README for general interface details. This transport always
1100 returns FALSE, indicating that the status which has been placed in the first
1101 address should be copied to any other addresses in a batch.
1103 Appendfile delivery is tricky and has led to various security problems in other
1104 mailers. The logic used here is therefore laid out in some detail. When this
1105 function is called, we are running in a subprocess which has had its gid and
1106 uid set to the appropriate values. Therefore, we cannot write directly to the
1107 exim logs. Any errors must be handled by setting appropriate return codes.
1108 Note that the default setting for addr->transport_return is DEFER, so it need
1109 not be set unless some other value is required.
1111 The code below calls geteuid() rather than getuid() to get the current uid
1112 because in weird configurations not running setuid root there may be a
1113 difference. In the standard configuration, where setuid() has been used in the
1114 delivery process, there will be no difference between the uid and the euid.
1116 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1117 alias expansion. Otherwise, there must be a configured file name or
1120 The following items apply in the case when a file name (as opposed to a
1121 directory name) is given, that is, when appending to a single file:
1123 (2f) Expand the file name.
1125 (3f) If the file name is /dev/null, return success (optimization).
1127 (4f) If the file_format options is set, open the file for reading, and check
1128 that the bytes at the start of the file match one of the given strings.
1129 If the check indicates a transport other than the current one should be
1130 used, pass control to that other transport. Otherwise continue. An empty
1131 or non-existent file matches the current transport. The file is closed
1134 (5f) If a lock file is required, create it (see extensive separate comments
1135 below about the algorithm for doing this). It is important to do this
1136 before opening the mailbox if NFS is in use.
1138 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1139 details of any symbolic link.
1141 (7f) If the file already exists:
1143 Check the owner and group if necessary, and defer if they are wrong.
1145 If it is a symbolic link AND the allow_symlink option is set (NOT the
1146 default), go back to (6f) but this time use stat() instead of lstat().
1148 If it's not a regular file (or FIFO when permitted), defer delivery.
1150 Check permissions. If the required permissions are *less* than the
1151 existing ones, or supplied by the address (often by the user via filter),
1152 chmod() the file. Otherwise, defer.
1154 Save the inode number.
1156 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1158 If open fails because the file does not exist, go to (6f); on any other
1161 Check the inode number hasn't changed - I realize this isn't perfect (an
1162 inode can be reused) but it's cheap and will catch some of the races.
1164 Check it's still a regular file (or FIFO if permitted).
1166 Check that the owner and permissions haven't changed.
1168 If file_format is set, check that the file still matches the format for
1169 the current transport. If not, defer delivery.
1171 (8f) If file does not exist initially:
1173 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1174 this is via a symbolic link (only possible if allow_symlinks is set), in
1175 which case don't use O_EXCL, as it doesn't work.
1177 If open fails because the file already exists, go to (6f). To avoid
1178 looping for ever in a situation where the file is continuously being
1179 created and deleted, all of this happens inside a loop that operates
1180 lock_retries times and includes the fcntl and flock locking. If the
1181 loop completes without the file getting opened, defer and request
1182 freezing, because something really weird is happening.
1184 If open fails for any other reason, defer for subsequent delivery except
1185 when this is a file delivery resulting from an alias or forward expansion
1186 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1187 most likely a user rather than a configuration error.
1189 (9f) We now have the file checked and open for writing. If so configured, lock
1190 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1191 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1192 still fails, give up and defer delivery.
1194 (10f)Save the access time (for subsequent restoration) and the size of the
1195 file, for comsat and for re-setting if delivery fails in the middle -
1196 e.g. for quota exceeded.
1198 The following items apply in the case when a directory name is given:
1200 (2d) Create a new file in the directory using a temporary name, by opening for
1201 writing and with O_CREAT. If maildir format is being used, the file
1202 is created in a temporary subdirectory with a prescribed name. If
1203 mailstore format is being used, the envelope file is first created with a
1204 temporary name, then the data file.
1206 The following items apply in all cases:
1208 (11) We now have the file open for writing, and locked if it was given as a
1209 file name. Write the message and flush the file, unless there is a setting
1210 of the local quota option, in which case we can check for its excession
1211 without doing any writing.
1213 In the case of MBX format mailboxes, the message is first written to a
1214 temporary file, in order to get its correct length. This is then copied to
1215 the real file, preceded by an MBX header.
1217 If there is a quota error on writing, defer the address. Timeout logic
1218 will determine for how long retries are attempted. We restore the mailbox
1219 to its original length if it's a single file. There doesn't seem to be a
1220 uniform error code for quota excession (it even differs between SunOS4
1221 and some versions of SunOS5) so a system-dependent macro called
1222 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1225 For any other error (most commonly disk full), do the same.
1227 The following applies after appending to a file:
1229 (12f)Restore the atime; notify_comsat if required; close the file (which
1230 unlocks it if it was locked). Delete the lock file if it exists.
1232 The following applies after writing a unique file in a directory:
1234 (12d)For maildir format, rename the file into the new directory. For mailstore
1235 format, rename the envelope file to its correct name. Otherwise, generate
1236 a unique name from the directory_file option, and rename to that, possibly
1237 trying a few times if the file exists and re-expanding the name gives a
1240 This transport yields FAIL only when a file name is generated by an alias or
1241 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1242 All other failures return DEFER (in addr->transport_return). */
1246 appendfile_transport_entry(
1247 transport_instance *tblock, /* data for this instantiation */
1248 address_item *addr) /* address we are working on */
1250 appendfile_transport_options_block *ob =
1251 (appendfile_transport_options_block *)(tblock->options_block);
1252 struct stat statbuf;
1253 uschar *fdname = NULL;
1254 uschar *filename = NULL;
1255 uschar *hitchname = NULL;
1256 uschar *dataname = NULL;
1257 uschar *lockname = NULL;
1258 uschar *newname = NULL;
1259 uschar *nametag = NULL;
1261 uschar *filecount_msg = US"";
1263 struct utimbuf times;
1264 struct timeval msg_tv;
1265 BOOL disable_quota = FALSE;
1266 BOOL isdirectory = FALSE;
1267 BOOL isfifo = FALSE;
1268 BOOL wait_for_tick = FALSE;
1269 uid_t uid = geteuid(); /* See note above */
1270 gid_t gid = getegid();
1272 int mode = (addr->mode > 0) ? addr->mode : ob->mode;
1273 off_t saved_size = -1;
1274 off_t mailbox_size = ob->mailbox_size_value;
1275 int mailbox_filecount = ob->mailbox_filecount_value;
1283 int mbx_lockfd = -1;
1284 uschar mbx_lockname[40];
1285 FILE *temp_file = NULL;
1286 #endif /* SUPPORT_MBX */
1288 #ifdef SUPPORT_MAILDIR
1289 int maildirsize_fd = -1; /* fd for maildirsize file */
1290 int maildir_save_errno;
1294 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1296 /* An "address_file" or "address_directory" transport is used to deliver to
1297 files specified via .forward or an alias file. Prior to release 4.20, the
1298 "file" and "directory" options were ignored in this case. This has been changed
1299 to allow the redirection data to specify what is in effect a folder, whose
1300 location is determined by the options on the transport.
1302 Compatibility with the case when neither option is set is retained by forcing a
1303 value for the file or directory name. A directory delivery is assumed if the
1304 last character of the path from the router is '/'.
1306 The file path is in the local part of the address, but not in the $local_part
1307 variable (that holds the parent local part). It is, however, in the
1308 $address_file variable. Below, we update the local part in the address if it
1309 changes by expansion, so that the final path ends up in the log. */
1311 if (testflag(addr, af_file) &&
1312 ob->filename == NULL &&
1313 ob->dirname == NULL)
1315 fdname = US"$address_file";
1316 if (address_file[Ustrlen(address_file)-1] == '/' ||
1317 ob->maildir_format ||
1318 ob->mailstore_format)
1322 /* Handle (a) an "address file" delivery where "file" or "directory" is
1323 explicitly set and (b) a non-address_file delivery, where one of "file" or
1324 "directory" must be set; initialization ensures that they are not both set. */
1328 fdname = ob->filename;
1331 fdname = ob->dirname;
1336 addr->transport_return = PANIC;
1337 addr->message = string_sprintf("Mandatory file or directory option "
1338 "missing from %s transport", tblock->name);
1343 /* Maildir and mailstore require a directory */
1345 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1347 addr->transport_return = PANIC;
1348 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1349 "to be specified for the %s transport",
1350 ob->maildir_format ? "dir" : "store", tblock->name);
1354 path = expand_string(fdname);
1358 addr->transport_return = PANIC;
1359 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1360 "name for %s transport) failed: %s", fdname, tblock->name,
1361 expand_string_message);
1367 addr->message = string_sprintf("appendfile: file or directory name "
1368 "\"%s\" is not absolute", path);
1369 addr->basic_errno = ERRNO_NOTABSOLUTE;
1373 /* For a file delivery, make sure the local part in the address(es) is updated
1374 to the true local part. */
1376 if (testflag(addr, af_file))
1377 for (address_item * addr2 = addr; addr2 != NULL; addr2 = addr2->next)
1378 addr2->local_part = string_copy(path);
1380 /* The available mailbox formats depend on whether it is a directory or a file
1386 #ifdef SUPPORT_MAILDIR
1387 (ob->maildir_format) ? mbf_maildir :
1389 #ifdef SUPPORT_MAILSTORE
1390 (ob->mailstore_format) ? mbf_mailstore :
1398 (ob->mbx_format) ? mbf_mbx :
1405 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1407 " warning=" OFF_T_FMT "%s\n"
1408 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1409 "maildir_use_size_file=%s\n",
1410 mode, ob->notify_comsat, ob->quota_value,
1411 ob->quota_no_check ? " (no_check)" : "",
1412 ob->quota_filecount_no_check ? " (no_check_filecount)" : "",
1413 ob->quota_warn_threshold_value,
1414 ob->quota_warn_threshold_is_percent ? "%" : "",
1415 isdirectory ? "directory" : "file",
1416 path, mailbox_formats[mbformat],
1417 (ob->message_prefix == NULL) ? US"null" : string_printing(ob->message_prefix),
1418 (ob->message_suffix == NULL) ? US"null" : string_printing(ob->message_suffix),
1419 (ob->maildir_use_size_file) ? "yes" : "no");
1421 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1422 ob->use_lockfile ? "lockfile " : "",
1423 ob->use_mbx_lock ? "mbx locking (" : "",
1424 ob->use_fcntl ? "fcntl " : "",
1425 ob->use_flock ? "flock" : "",
1426 ob->use_mbx_lock ? ")" : "");
1429 /* If the -N option is set, can't do any more. */
1434 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1436 addr->transport_return = OK;
1440 /* Handle the case of a file name. If the file name is /dev/null, we can save
1441 ourselves some effort and just give a success return right away. */
1445 BOOL use_lstat = TRUE;
1446 BOOL file_opened = FALSE;
1447 BOOL allow_creation_here = TRUE;
1449 if (Ustrcmp(path, "/dev/null") == 0)
1451 addr->transport_return = OK;
1455 /* Set the name of the file to be opened, and the file to which the data
1456 is written, and find out if we are permitted to create a non-existent file. */
1458 dataname = filename = path;
1459 allow_creation_here = check_creation(filename, ob->create_file);
1461 /* If ob->create_directory is set, attempt to create the directories in
1462 which this mailbox lives, but only if we are permitted to create the file
1463 itself. We know we are dealing with an absolute path, because this was
1466 if (ob->create_directory && allow_creation_here)
1468 uschar *p = Ustrrchr(path, '/');
1470 if (!directory_make(NULL, path, ob->dirmode, FALSE))
1472 addr->basic_errno = errno;
1474 string_sprintf("failed to create directories for %s: %s", path,
1476 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1482 /* If file_format is set we must check that any existing file matches one of
1483 the configured formats by checking the bytes it starts with. A match then
1484 indicates a specific transport - if it is not this one, pass control to it.
1485 Otherwise carry on here. An empty or non-existent file matches the current
1486 transport. We don't need to distinguish between non-existence and other open
1487 failures because if an existing file fails to open here, it will also fail
1488 again later when O_RDWR is used. */
1490 if (ob->file_format != NULL)
1492 int cfd = Uopen(path, O_RDONLY, 0);
1495 transport_instance *tt = check_file_format(cfd, tblock, addr);
1498 /* If another transport is indicated, call it and return; if no transport
1499 was found, just return - the error data will have been set up.*/
1505 set_process_info("delivering %s to %s using %s", message_id,
1506 addr->local_part, tt->name);
1507 debug_print_string(tt->debug_string);
1508 addr->transport = tt;
1509 (tt->info->code)(tt, addr);
1516 /* The locking of mailbox files is worse than the naming of cats, which is
1517 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1518 three different names, so several different styles of locking are used.
1520 Research in other programs that lock mailboxes shows that there is no
1521 universally standard method. Having mailboxes NFS-mounted on the system that
1522 is delivering mail is not the best thing, but people do run like this,
1523 and so the code must do its best to cope.
1525 Three different locking mechanisms are supported. The initialization function
1526 checks that at least one is configured.
1530 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1531 will work over NFS. Only after that is done do we actually open the mailbox
1532 and apply locks to it (if configured).
1534 Originally, Exim got the file opened before doing anything about locking.
1535 However, a very occasional problem was observed on Solaris 2 when delivering
1536 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1537 gets remembered at open time. If another process on another host (that's
1538 important) has the file open and locked and writes to it and then releases
1539 the lock while the first process is waiting to get the lock, the first
1540 process may fail to write at the new end point of the file - despite the very
1541 definite statement about O_APPEND in the man page for write(). Experiments
1542 have reproduced this problem, but I do not know any way of forcing a host to
1543 update its attribute cache for an open NFS file. It would be nice if it did
1544 so when a lock was taken out, but this does not seem to happen. Anyway, to
1545 reduce the risk of this problem happening, we now create the lock file
1546 (if configured) *before* opening the mailbox. That will prevent two different
1547 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1548 however, but Pine at least seems to operate in the same way.
1550 Lockfiles should normally be used when NFS is involved, because of the above
1553 The logic for creating the lock file is:
1555 . The name of the lock file is <mailbox-name>.lock
1557 . First, create a "hitching post" name by adding the primary host name,
1558 current time and pid to the lock file name. This should be unique.
1560 . Create the hitching post file using WRONLY + CREAT + EXCL.
1562 . If that fails EACCES, we assume it means that the user is unable to create
1563 files in the mail spool directory. Some installations might operate in this
1564 manner, so there is a configuration option to allow this state not to be an
1565 error - we proceed to lock using fcntl only, after the file is open.
1567 . Otherwise, an error causes a deferment of the address.
1569 . Hard link the hitching post to the lock file name.
1571 . If the link succeeds, we have successfully created the lock file. Simply
1572 close and unlink the hitching post file.
1574 . If the link does not succeed, proceed as follows:
1576 o Fstat the hitching post file, and then close and unlink it.
1578 o Now examine the stat data. If the number of links to the file is exactly
1579 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1580 the return never made it back, so the link() function gave a failure
1583 . This method allows for the lock file to be created by some other process
1584 right up to the moment of the attempt to hard link it, and is also robust
1585 against NFS server crash-reboots, which would probably result in timeouts
1586 in the middle of link().
1588 . System crashes may cause lock files to get left lying around, and some means
1589 of flushing them is required. The approach of writing a pid (used by smail
1590 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1591 timeout, which seems a better approach. Since any program that writes to a
1592 mailbox using a lock file should complete its task very quickly, Pine
1593 removes lock files that are older than 5 minutes. We allow the value to be
1594 configurable on the transport.
1598 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1599 mailbox once it is open. This is done by default with a non-blocking lock.
1600 Failures to lock cause retries after a sleep, but only for a certain number
1601 of tries. A blocking lock is deliberately not used so that we don't hold the
1602 mailbox open. This minimizes the possibility of the NFS problem described
1603 under LOCK FILES above, if for some reason NFS deliveries are happening
1604 without lock files. However, the use of a non-blocking lock and sleep, though
1605 the safest approach, does not give the best performance on very busy systems.
1606 A blocking lock plus timeout does better. Therefore Exim has an option to
1607 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1608 enables the use of blocking fcntl() calls.
1612 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1613 same manner as for fcntl locking above. No-blocking/timeout is also set as
1614 above in lock_flock_timeout. Not all operating systems provide or support
1615 flock(). For those that don't (as determined by the definition of LOCK_SH in
1616 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1617 is implemented (not precisely) on top of fcntl(), which means there's no
1618 point in actually using it.
1622 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1623 then the rules used for locking in c-client are used. Exim takes out a shared
1624 lock on the mailbox file, and an exclusive lock on the file whose name is
1625 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1626 any other MBX client from getting an exclusive lock on it and expunging it.
1627 It also stops any other MBX client from unlinking the /tmp lock when it has
1630 The exclusive lock on the /tmp file prevents any other MBX client from
1631 updating the mailbox in any way. When writing is finished, if an exclusive
1632 lock on the mailbox can be obtained, indicating there are no current sharers,
1633 the /tmp file is unlinked.
1635 MBX locking can use either fcntl() or flock() locking. If neither
1636 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1637 The calls for getting these locks are by default non-blocking, as for non-mbx
1638 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1639 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1640 probably makes sense to set timeouts for any MBX deliveries. */
1643 /* Build a lock file if configured to do so - the existence of a lock
1644 file is subsequently checked by looking for a non-negative value of the
1645 file descriptor hd - even though the file is no longer open. */
1647 if (ob->use_lockfile)
1649 /* cf. exim_lock.c */
1650 lockname = string_sprintf("%s.lock", filename);
1651 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1652 (unsigned int)(time(NULL)), (unsigned int)getpid());
1654 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1657 /* Lock file creation retry loop */
1659 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1662 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1666 addr->basic_errno = errno;
1668 string_sprintf("creating lock file hitching post %s "
1669 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1670 (long int)getegid());
1674 /* Attempt to hitch the hitching post to the lock file. If link()
1675 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1676 file, and get rid of the hitching post. If the number of links was 2,
1677 the link was created, despite the failure of link(). If the hitch was
1678 not successful, try again, having unlinked the lock file if it is too
1681 There's a version of Linux (2.0.27) which doesn't update its local cache
1682 of the inode after link() by default - which many think is a bug - but
1683 if the link succeeds, this code will be OK. It just won't work in the
1684 case when link() fails after having actually created the link. The Linux
1685 NFS person is fixing this; a temporary patch is available if anyone is
1686 sufficiently worried. */
1688 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1691 if (rc != 0 && statbuf.st_nlink != 2)
1693 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1694 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1696 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1699 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1703 DEBUG(D_transport) debug_printf("lock file created\n");
1707 /* Check for too many tries at creating the lock file */
1709 if (i >= ob->lock_retries)
1711 addr->basic_errno = ERRNO_LOCKFAILED;
1712 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1719 /* We now have to get the file open. First, stat() it and act on existence or
1720 non-existence. This is in a loop to handle the case of a file's being created
1721 or deleted as we watch, and also to handle retries when the locking fails.
1722 Rather than holding the file open while waiting for the fcntl() and/or
1723 flock() lock, we close and do the whole thing again. This should be safer,
1724 especially for NFS files, which might get altered from other hosts, making
1725 their cached sizes incorrect.
1727 With the default settings, no symlinks are permitted, but there is an option
1728 to permit symlinks for those sysadmins that know what they are doing.
1729 Shudder. However, insist that the initial symlink is owned by the right user.
1730 Thus lstat() is used initially; if a symlink is discovered, the loop is
1731 repeated such that stat() is used, to look at the end file. */
1733 for (i = 0; i < ob->lock_retries; i++)
1735 int sleep_before_retry = TRUE;
1736 file_opened = FALSE;
1738 if((use_lstat ? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1740 /* Let's hope that failure to stat (other than non-existence) is a
1743 if (errno != ENOENT)
1745 addr->basic_errno = errno;
1746 addr->message = string_sprintf("attempting to stat mailbox %s",
1751 /* File does not exist. If it is required to pre-exist this state is an
1754 if (ob->file_must_exist)
1756 addr->basic_errno = errno;
1757 addr->message = string_sprintf("mailbox %s does not exist, "
1758 "but file_must_exist is set", filename);
1762 /* If not permitted to create this file because it isn't in or below
1763 the home directory, generate an error. */
1765 if (!allow_creation_here)
1767 addr->basic_errno = ERRNO_BADCREATE;
1768 addr->message = string_sprintf("mailbox %s does not exist, "
1769 "but creation outside the home directory is not permitted",
1774 /* Attempt to create and open the file. If open fails because of
1775 pre-existence, go round the loop again. For any other error, defer the
1776 address, except for an alias or forward generated file name with EPERM,
1777 ENOENT, or EACCES, as those are most likely to be user errors rather
1778 than Exim config errors. When a symbolic link is permitted and points
1779 to a non-existent file, we get here with use_lstat = FALSE. In this case
1780 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1781 consistency and because MBX locking requires it in order to be able to
1782 get a shared lock. */
1784 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1785 (use_lstat ? O_EXCL : 0), mode);
1788 if (errno == EEXIST) continue;
1789 addr->basic_errno = errno;
1790 addr->message = string_sprintf("while creating mailbox %s",
1792 if (testflag(addr, af_file) &&
1793 (errno == EPERM || errno == ENOENT || errno == EACCES))
1794 addr->transport_return = FAIL;
1798 /* We have successfully created and opened the file. Ensure that the group
1799 and the mode are correct. */
1801 if(exim_chown(filename, uid, gid) || Uchmod(filename, mode))
1803 addr->basic_errno = errno;
1804 addr->message = string_sprintf("while setting perms on mailbox %s",
1806 addr->transport_return = FAIL;
1812 /* The file already exists. Test its type, ownership, and permissions, and
1813 save the inode for checking later. If symlinks are permitted (not the
1814 default or recommended state) it may be a symlink that already exists.
1815 Check its ownership and then look for the file at the end of the link(s).
1816 This at least prevents one user creating a symlink for another user in
1817 a sticky directory. */
1821 int oldmode = (int)statbuf.st_mode;
1822 ino_t inode = statbuf.st_ino;
1823 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1825 isfifo = FALSE; /* In case things are changing */
1827 /* Check owner if required - the default. */
1829 if (ob->check_owner && statbuf.st_uid != uid)
1831 addr->basic_errno = ERRNO_BADUGID;
1832 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1833 "(%ld != %ld)", filename,
1834 islink ? " (symlink)" : "",
1835 (long int)(statbuf.st_uid), (long int)uid);
1839 /* Group is checked only if check_group is set. */
1841 if (ob->check_group && statbuf.st_gid != gid)
1843 addr->basic_errno = ERRNO_BADUGID;
1844 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1845 filename, islink ? " (symlink)" : "", statbuf.st_gid, gid);
1849 /* Just in case this is a sticky-bit mail directory, we don't want
1850 users to be able to create hard links to other users' files. */
1852 if (statbuf.st_nlink != 1)
1854 addr->basic_errno = ERRNO_NOTREGULAR;
1855 addr->message = string_sprintf("mailbox %s%s has too many links (%d)",
1856 filename, islink ? " (symlink)" : "", statbuf.st_nlink);
1861 /* If symlinks are permitted (not recommended), the lstat() above will
1862 have found the symlink. Its ownership has just been checked; go round
1863 the loop again, using stat() instead of lstat(). That will never yield a
1866 if (islink && ob->allow_symlink)
1869 i--; /* Don't count this time round */
1873 /* An actual file exists. Check that it is a regular file, or FIFO
1876 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1878 else if ((oldmode & S_IFMT) != S_IFREG)
1880 addr->basic_errno = ERRNO_NOTREGULAR;
1881 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1882 filename, ob->allow_fifo ? " or named pipe" : "");
1886 /* If the mode is not what it would be for a newly created file, change
1887 the permissions if the mode is supplied for the address. Otherwise,
1888 reduce but do not extend the permissions. If the newly created
1889 permissions are greater than the existing permissions, don't change
1890 things when the mode is not from the address. */
1892 if ((oldmode = (oldmode & 07777)) != mode)
1894 int diffs = oldmode ^ mode;
1895 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1897 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1898 if (Uchmod(filename, mode) < 0)
1900 addr->basic_errno = errno;
1901 addr->message = string_sprintf("attempting to chmod mailbox %s",
1908 /* Mode not from address, and newly-created permissions are greater
1909 than existing permissions. Default is to complain, but it can be
1910 configured to go ahead and try to deliver anyway if that's what
1911 the administration wants. */
1913 else if (ob->mode_fail_narrower)
1915 addr->basic_errno = ERRNO_BADMODE;
1916 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1917 "(%o expected)", filename, oldmode, mode);
1922 /* We are happy with the existing file. Open it, and then do further
1923 tests to ensure that it is the same file that we were just looking at.
1924 If the file does not now exist, restart this loop, going back to using
1925 lstat again. For an NFS error, just defer; other opening errors are
1926 more serious. The file is opened RDWR so that its format can be checked,
1927 and also MBX locking requires the use of a shared (read) lock. However,
1928 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1929 reading the pipe. */
1931 fd = Uopen(filename, isfifo ? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1935 if (errno == ENOENT)
1940 addr->basic_errno = errno;
1943 addr->message = string_sprintf("while opening named pipe %s "
1944 "(could mean no process is reading it)", filename);
1946 else if (errno != EWOULDBLOCK)
1948 addr->message = string_sprintf("while opening mailbox %s", filename);
1953 /* This fstat really shouldn't fail, as we have an open file! There's a
1954 dilemma here. We use fstat in order to be sure we are peering at the file
1955 we have got open. However, that won't tell us if the file was reached
1956 via a symbolic link. We checked this above, but there is a race exposure
1957 if the link was created between the previous lstat and the open. However,
1958 it would have to be created with the same inode in order to pass the
1959 check below. If ob->allow_symlink is set, causing the use of stat rather
1960 than lstat above, symbolic links may be there anyway, and the checking is
1963 if (fstat(fd, &statbuf) < 0)
1965 addr->basic_errno = errno;
1966 addr->message = string_sprintf("attempting to stat open mailbox %s",
1971 /* Check the inode; this is isn't a perfect check, but gives some
1974 if (inode != statbuf.st_ino)
1976 addr->basic_errno = ERRNO_INODECHANGED;
1977 addr->message = string_sprintf("opened mailbox %s inode number changed "
1978 "from " INO_T_FMT " to " INO_T_FMT, filename, inode, statbuf.st_ino);
1979 addr->special_action = SPECIAL_FREEZE;
1983 /* Check it's still a regular file or FIFO, and the uid, gid, and
1984 permissions have not changed. */
1986 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1987 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1989 addr->basic_errno = ERRNO_NOTREGULAR;
1991 string_sprintf("opened mailbox %s is no longer a %s", filename,
1992 isfifo ? "named pipe" : "regular file");
1993 addr->special_action = SPECIAL_FREEZE;
1997 if ((ob->check_owner && statbuf.st_uid != uid) ||
1998 (ob->check_group && statbuf.st_gid != gid))
2000 addr->basic_errno = ERRNO_BADUGID;
2002 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
2003 addr->special_action = SPECIAL_FREEZE;
2007 if ((statbuf.st_mode & 07777) != oldmode)
2009 addr->basic_errno = ERRNO_BADMODE;
2010 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
2011 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
2012 addr->special_action = SPECIAL_FREEZE;
2016 /* If file_format is set, check that the format of the file has not
2017 changed. Error data is set by the testing function. */
2019 if (ob->file_format != NULL &&
2020 check_file_format(fd, tblock, addr) != tblock)
2022 addr->message = US"open mailbox has changed format";
2026 /* The file is OK. Carry on to do the locking. */
2029 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
2030 locking rules if configured to do so. If a lock file is also required, it
2031 was created above and hd was left >= 0. At least one form of locking is
2032 required by the initialization function. If locking fails here, close the
2033 file and go round the loop all over again, after waiting for a bit, unless
2034 blocking locking was used. */
2037 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
2038 sleep_before_retry = FALSE;
2040 /* Simple fcntl() and/or flock() locking */
2042 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
2044 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2045 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
2048 /* MBX locking rules */
2051 else if (ob->use_mbx_lock)
2054 struct stat lstatbuf, statbuf2;
2055 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2056 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
2057 fstat(fd, &statbuf) >= 0)
2059 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
2060 (long)statbuf.st_ino);
2063 * 2010-05-29: SECURITY
2064 * Dan Rosenberg reported the presence of a race-condition in the
2065 * original code here. Beware that many systems still allow symlinks
2066 * to be followed in /tmp so an attacker can create a symlink pointing
2067 * elsewhere between a stat and an open, which we should avoid
2070 * It's unfortunate that we can't just use all the heavily debugged
2071 * locking from above.
2073 * Also: remember to mirror changes into exim_lock.c */
2075 /* first leave the old pre-check in place, it provides better
2076 * diagnostics for common cases */
2077 if (Ulstat(mbx_lockname, &statbuf) >= 0)
2079 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
2081 addr->basic_errno = ERRNO_LOCKFAILED;
2082 addr->message = string_sprintf("symbolic link on MBX lock file %s",
2086 if (statbuf.st_nlink > 1)
2088 addr->basic_errno = ERRNO_LOCKFAILED;
2089 addr->message = string_sprintf("hard link to MBX lock file %s",
2095 /* If we could just declare "we must be the ones who create this
2096 * file" then a hitching post in a subdir would work, since a
2097 * subdir directly in /tmp/ which we create wouldn't follow links
2098 * but this isn't our locking logic, so we can't safely change the
2099 * file existence rules. */
2101 /* On systems which support O_NOFOLLOW, it's the easiest and most
2102 * obviously correct security fix */
2103 mbx_tmp_oflags = O_RDWR | O_CREAT;
2105 mbx_tmp_oflags |= O_NOFOLLOW;
2107 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
2110 addr->basic_errno = ERRNO_LOCKFAILED;
2111 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2112 mbx_lockname, strerror(errno));
2116 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2118 addr->basic_errno = ERRNO_LOCKFAILED;
2119 addr->message = string_sprintf("attempting to lstat open MBX "
2120 "lock file %s: %s", mbx_lockname, strerror(errno));
2123 if (fstat(mbx_lockfd, &statbuf2) < 0)
2125 addr->basic_errno = ERRNO_LOCKFAILED;
2126 addr->message = string_sprintf("attempting to stat fd of open MBX "
2127 "lock file %s: %s", mbx_lockname, strerror(errno));
2133 * statbuf: if exists, is file which existed prior to opening the
2134 * lockfile, might have been replaced since then
2135 * statbuf2: result of stat'ing the open fd, is what was actually
2137 * lstatbuf: result of lstat'ing the filename immediately after
2138 * the open but there's a race condition again between
2139 * those two steps: before open, symlink to foo, after
2140 * open but before lstat have one of:
2141 * * was no symlink, so is the opened file
2142 * (we created it, no messing possible after that point)
2144 * * symlink elsewhere
2145 * * hardlink elsewhere
2147 * Don't want to compare to device of /tmp because some modern systems
2148 * have regressed to having /tmp be the safe actual filesystem as
2149 * valuable data, so is mostly worthless, unless we assume that *only*
2150 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2151 * for further consideration.
2152 * No point in doing a readlink on the lockfile as that will always be
2153 * at a different point in time from when we open it, so tells us
2154 * nothing; attempts to clean up and delete after ourselves would risk
2155 * deleting a *third* filename.
2157 if ((statbuf2.st_nlink > 1) ||
2158 (lstatbuf.st_nlink > 1) ||
2159 (!S_ISREG(lstatbuf.st_mode)) ||
2160 (lstatbuf.st_dev != statbuf2.st_dev) ||
2161 (lstatbuf.st_ino != statbuf2.st_ino))
2163 addr->basic_errno = ERRNO_LOCKFAILED;
2164 addr->message = string_sprintf("RACE CONDITION detected: "
2165 "mismatch post-initial-checks between \"%s\" and opened "
2166 "fd lead us to abort!", mbx_lockname);
2170 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2172 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2173 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2175 struct stat ostatbuf;
2177 /* This tests for a specific race condition. Ensure that we still
2178 have the same file. */
2180 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2181 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2182 statbuf.st_dev == ostatbuf.st_dev &&
2183 statbuf.st_ino == ostatbuf.st_ino)
2185 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2186 "between creation and locking\n", mbx_lockname);
2189 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2191 (void)close(mbx_lockfd);
2196 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2197 filename, strerror(errno));
2200 #endif /* SUPPORT_MBX */
2202 else break; /* No on-file locking required; break the open/lock loop */
2205 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2209 use_lstat = TRUE; /* Reset to use lstat first */
2212 /* If a blocking call timed out, break the retry loop if the total time
2213 so far is not less than than retries * interval. Use the larger of the
2214 flock() and fcntl() timeouts. */
2217 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2218 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2219 ob->lock_retries * ob->lock_interval)
2220 i = ob->lock_retries;
2222 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2223 flock() that caused the problem. */
2225 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2228 /* Test for exceeding the maximum number of tries. Either the file remains
2229 locked, or, if we haven't got it open, something is terribly wrong... */
2231 if (i >= ob->lock_retries)
2235 addr->basic_errno = ERRNO_EXISTRACE;
2236 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2237 addr->special_action = SPECIAL_FREEZE;
2241 addr->basic_errno = ERRNO_LOCKFAILED;
2242 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2248 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2250 /* Save access time (for subsequent restoration), modification time (for
2251 restoration if updating fails), size of file (for comsat and for re-setting if
2252 delivery fails in the middle - e.g. for quota exceeded). */
2254 if (fstat(fd, &statbuf) < 0)
2256 addr->basic_errno = errno;
2257 addr->message = string_sprintf("while fstatting opened mailbox %s",
2262 times.actime = statbuf.st_atime;
2263 times.modtime = statbuf.st_mtime;
2264 saved_size = statbuf.st_size;
2265 if (mailbox_size < 0) mailbox_size = saved_size;
2266 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2269 /* Prepare for writing to a new file (as opposed to appending to an old one).
2270 There are several different formats, but there is preliminary stuff concerned
2271 with quotas that applies to all of them. Finding the current size by directory
2272 scanning is expensive; for maildirs some fudges have been invented:
2274 (1) A regex can be used to extract a file size from its name;
2275 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2281 uschar *check_path = path; /* Default quota check path */
2282 const pcre *regex = NULL; /* Regex for file size from file name */
2284 if (!check_creation(string_sprintf("%s/any", path), ob->create_file))
2286 addr->basic_errno = ERRNO_BADCREATE;
2287 addr->message = string_sprintf("tried to create file in %s, but "
2288 "file creation outside the home directory is not permitted", path);
2292 #ifdef SUPPORT_MAILDIR
2293 /* For a maildir delivery, ensure that all the relevant directories exist,
2294 and a maildirfolder file if necessary. */
2296 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2297 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2299 #endif /* SUPPORT_MAILDIR */
2301 /* If we are going to do a quota check, of if maildir_use_size_file is set
2302 for a maildir delivery, compile the regular expression if there is one. We
2303 may also need to adjust the path that is used. We need to do this for
2304 maildir_use_size_file even if the quota is unset, because we still want to
2305 create the file. When maildir support is not compiled,
2306 ob->maildir_use_size_file is always FALSE. */
2308 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2310 const uschar *error;
2313 /* Compile the regex if there is one. */
2315 if (ob->quota_size_regex != NULL)
2317 regex = pcre_compile(CS ob->quota_size_regex, PCRE_COPT,
2318 (const char **)&error, &offset, NULL);
2321 addr->message = string_sprintf("appendfile: regular expression "
2322 "error: %s at offset %d while compiling %s", error, offset,
2323 ob->quota_size_regex);
2326 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2327 ob->quota_size_regex);
2330 /* Use an explicitly configured directory if set */
2332 if (ob->quota_directory != NULL)
2334 check_path = expand_string(ob->quota_directory);
2335 if (check_path == NULL)
2337 addr->transport_return = PANIC;
2338 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2339 "name for %s transport) failed: %s", ob->quota_directory,
2340 tblock->name, expand_string_message);
2344 if (check_path[0] != '/')
2346 addr->message = string_sprintf("appendfile: quota_directory name "
2347 "\"%s\" is not absolute", check_path);
2348 addr->basic_errno = ERRNO_NOTABSOLUTE;
2353 #ifdef SUPPORT_MAILDIR
2354 /* Otherwise, if we are handling a maildir delivery, and the directory
2355 contains a file called maildirfolder, this is a maildir++ feature telling
2356 us that this is a sub-directory of the real inbox. We should therefore do
2357 the quota check on the parent directory. Beware of the special case when
2358 the directory name itself ends in a slash. */
2360 else if (mbformat == mbf_maildir)
2362 struct stat statbuf;
2363 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2365 uschar *new_check_path = string_copy(check_path);
2366 uschar *slash = Ustrrchr(new_check_path, '/');
2372 slash = Ustrrchr(new_check_path, '/');
2377 check_path = new_check_path;
2378 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2379 "quota check directory changed to %s\n", check_path);
2384 #endif /* SUPPORT_MAILDIR */
2387 /* If we are using maildirsize files, we need to ensure that such a file
2388 exists and, if necessary, recalculate its contents. As a byproduct of this,
2389 we obtain the current size of the maildir. If no quota is to be enforced
2390 (ob->quota_value == 0), we still need the size if a threshold check will
2393 Another regular expression is used to determine which directories inside the
2394 maildir are going to be counted. */
2396 #ifdef SUPPORT_MAILDIR
2397 if (ob->maildir_use_size_file)
2399 const pcre *dir_regex = NULL;
2400 const uschar *error;
2403 if (ob->maildir_dir_regex != NULL)
2405 int check_path_len = Ustrlen(check_path);
2407 dir_regex = pcre_compile(CS ob->maildir_dir_regex, PCRE_COPT,
2408 (const char **)&error, &offset, NULL);
2409 if (dir_regex == NULL)
2411 addr->message = string_sprintf("appendfile: regular expression "
2412 "error: %s at offset %d while compiling %s", error, offset,
2413 ob->maildir_dir_regex);
2418 debug_printf("using regex for maildir directory selection: %s\n",
2419 ob->maildir_dir_regex);
2421 /* Check to see if we are delivering into an ignored directory, that is,
2422 if the delivery path starts with the quota check path, and the rest
2423 of the deliver path matches the regex; if so, set a flag to disable quota
2424 checking and maildirsize updating. */
2426 if (Ustrncmp(path, check_path, check_path_len) == 0)
2428 uschar *s = path + check_path_len;
2429 while (*s == '/') s++;
2430 s = (*s == 0) ? US "new" : string_sprintf("%s/new", s);
2431 if (pcre_exec(dir_regex, NULL, CS s, Ustrlen(s), 0, 0, NULL, 0) < 0)
2433 disable_quota = TRUE;
2434 DEBUG(D_transport) debug_printf("delivery directory does not match "
2435 "maildir_quota_directory_regex: disabling quota\n");
2440 /* Quota enforcement; create and check the file. There is some discussion
2441 about whether this should happen if the quota is unset. At present, Exim
2442 always creates the file. If we ever want to change this, uncomment
2443 appropriate lines below, possibly doing a check on some option. */
2445 /* if (???? || ob->quota_value > 0) */
2452 maildirsize_fd = maildir_ensure_sizefile(check_path, ob, regex, dir_regex,
2455 if (maildirsize_fd == -1)
2457 addr->basic_errno = errno;
2458 addr->message = string_sprintf("while opening or reading "
2459 "%s/maildirsize", check_path);
2462 /* can also return -2, which means that the file was removed because of
2463 raciness; but in this case, the size & filecount will still have been
2466 if (mailbox_size < 0) mailbox_size = size;
2467 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2470 /* No quota enforcement; ensure file does *not* exist; calculate size if
2475 * time_t old_latest;
2476 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2477 * if (THRESHOLD_CHECK)
2478 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2479 * regex, dir_regex, FALSE);
2484 #endif /* SUPPORT_MAILDIR */
2486 /* Otherwise if we are going to do a quota check later on, and the mailbox
2487 size is not set, find the current size of the mailbox. Ditto for the file
2488 count. Note that ob->quota_filecount_value cannot be set without
2489 ob->quota_value being set. */
2491 if (!disable_quota &&
2492 (ob->quota_value > 0 || THRESHOLD_CHECK) &&
2493 (mailbox_size < 0 ||
2494 (mailbox_filecount < 0 && ob->quota_filecount_value > 0)))
2499 debug_printf("quota checks on directory %s\n", check_path);
2500 size = check_dir_size(check_path, &filecount, regex);
2501 if (mailbox_size < 0) mailbox_size = size;
2502 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2505 /* Handle the case of creating a unique file in a given directory (not in
2506 maildir or mailstore format - this is how smail did it). A temporary name is
2507 used to create the file. Later, when it is written, the name is changed to a
2508 unique one. There is no need to lock the file. An attempt is made to create
2509 the directory if it does not exist. */
2511 if (mbformat == mbf_smail)
2514 debug_printf("delivering to new file in %s\n", path);
2515 filename = dataname =
2516 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2517 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2518 if (fd < 0 && /* failed to open, and */
2519 (errno != ENOENT || /* either not non-exist */
2520 !ob->create_directory || /* or not allowed to make */
2521 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2522 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2524 addr->basic_errno = errno;
2525 addr->message = string_sprintf("while creating file %s", filename);
2530 #ifdef SUPPORT_MAILDIR
2532 /* Handle the case of a unique file in maildir format. The file is written to
2533 the tmp subdirectory, with a prescribed form of name. */
2535 else if (mbformat == mbf_maildir)
2538 debug_printf("delivering in maildir format in %s\n", path);
2540 nametag = ob->maildir_tag;
2542 /* Check that nametag expands successfully; a hard failure causes a panic
2543 return. The actual expansion for use happens again later, when
2544 $message_size is accurately known. */
2546 if (nametag != NULL && expand_string(nametag) == NULL &&
2547 !f.expand_string_forcedfail)
2549 addr->transport_return = PANIC;
2550 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2551 "for %s transport) failed: %s", nametag, tblock->name,
2552 expand_string_message);
2556 /* We ensured the existence of all the relevant directories above. Attempt
2557 to open the temporary file a limited number of times. I think this rather
2558 scary-looking for statement is actually OK. If open succeeds, the loop is
2559 broken; if not, there is a test on the value of i. Get the time again
2560 afresh each time round the loop. Its value goes into a variable that is
2561 checked at the end, to make sure we don't release this process until the
2562 clock has ticked. */
2564 for (int i = 1;; i++)
2568 (void)gettimeofday(&msg_tv, NULL);
2569 basename = string_sprintf(TIME_T_FMT ".H%luP" PID_T_FMT ".%s",
2570 msg_tv.tv_sec, msg_tv.tv_usec, getpid(), primary_hostname);
2572 filename = dataname = string_sprintf("tmp/%s", basename);
2573 newname = string_sprintf("new/%s", basename);
2575 if (Ustat(filename, &statbuf) == 0)
2577 else if (errno == ENOENT)
2579 fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode);
2581 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2582 filename, strerror(errno));
2585 /* Too many retries - give up */
2587 if (i >= ob->maildir_retries)
2589 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2590 filename, i, (i == 1) ? "y" : "ies");
2591 addr->basic_errno = errno;
2592 if (errno == errno_quota || errno == ENOSPC)
2593 addr->user_message = US"mailbox is full";
2597 /* Open or stat failed but we haven't tried too many times yet. */
2602 /* Note that we have to ensure the clock has ticked before leaving */
2604 wait_for_tick = TRUE;
2606 /* Why are these here? Put in because they are present in the non-maildir
2607 directory case above. */
2609 if(exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2611 addr->basic_errno = errno;
2612 addr->message = string_sprintf("while setting perms on maildir %s",
2618 #endif /* SUPPORT_MAILDIR */
2620 #ifdef SUPPORT_MAILSTORE
2622 /* Handle the case of a unique file in mailstore format. First write the
2623 envelope to a temporary file, then open the main file. The unique base name
2624 for the files consists of the message id plus the pid of this delivery
2630 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2631 string_base62((long int)getpid()));
2634 debug_printf("delivering in mailstore format in %s\n", path);
2636 filename = string_sprintf("%s.tmp", mailstore_basename);
2637 newname = string_sprintf("%s.env", mailstore_basename);
2638 dataname = string_sprintf("%s.msg", mailstore_basename);
2640 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2641 if (fd < 0 && /* failed to open, and */
2642 (errno != ENOENT || /* either not non-exist */
2643 !ob->create_directory || /* or not allowed to make */
2644 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2645 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2647 addr->basic_errno = errno;
2648 addr->message = string_sprintf("while creating file %s", filename);
2652 /* Why are these here? Put in because they are present in the non-maildir
2653 directory case above. */
2655 if(exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2657 addr->basic_errno = errno;
2658 addr->message = string_sprintf("while setting perms on file %s",
2663 /* Built a C stream from the open file descriptor. */
2665 if ((env_file = fdopen(fd, "wb")) == NULL)
2667 addr->basic_errno = errno;
2668 addr->transport_return = PANIC;
2669 addr->message = string_sprintf("fdopen of %s ("
2670 "for %s transport) failed", filename, tblock->name);
2676 /* Write the envelope file, then close it. */
2678 if (ob->mailstore_prefix != NULL)
2680 uschar *s = expand_string(ob->mailstore_prefix);
2683 if (!f.expand_string_forcedfail)
2685 addr->transport_return = PANIC;
2686 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2687 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2688 tblock->name, expand_string_message);
2689 (void)fclose(env_file);
2697 fprintf(env_file, "%s", CS s);
2698 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2702 fprintf(env_file, "%s\n", sender_address);
2704 for (address_item * taddr = addr; taddr; taddr = taddr->next)
2705 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2707 if (ob->mailstore_suffix != NULL)
2709 uschar *s = expand_string(ob->mailstore_suffix);
2712 if (!f.expand_string_forcedfail)
2714 addr->transport_return = PANIC;
2715 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2716 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2717 tblock->name, expand_string_message);
2718 (void)fclose(env_file);
2726 fprintf(env_file, "%s", CS s);
2727 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2731 if (fclose(env_file) != 0)
2733 addr->basic_errno = errno;
2734 addr->message = string_sprintf("while closing %s", filename);
2739 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2741 /* Now open the data file, and ensure that it has the correct ownership and
2744 fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode);
2747 addr->basic_errno = errno;
2748 addr->message = string_sprintf("while creating file %s", dataname);
2752 if(exim_chown(dataname, uid, gid) || Uchmod(dataname, mode))
2754 addr->basic_errno = errno;
2755 addr->message = string_sprintf("while setting perms on file %s",
2761 #endif /* SUPPORT_MAILSTORE */
2764 /* In all cases of writing to a new file, ensure that the file which is
2765 going to be renamed has the correct ownership and mode. */
2767 if(exim_chown(filename, uid, gid) || Uchmod(filename, mode))
2769 addr->basic_errno = errno;
2770 addr->message = string_sprintf("while setting perms on file %s",
2777 /* At last we can write the message to the file, preceded by any configured
2778 prefix line, and followed by any configured suffix line. If there are any
2779 writing errors, we must defer. */
2781 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2786 /* If there is a local quota setting, check that we are not going to exceed it
2787 with this message if quota_is_inclusive is set; if it is not set, the check
2788 is for the mailbox already being over quota (i.e. the current message is not
2789 included in the check). */
2791 if (!disable_quota && ob->quota_value > 0)
2795 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2796 " this message = %d (%sincluded)\n",
2797 ob->quota_value, mailbox_size, message_size,
2798 ob->quota_is_inclusive ? "" : "not ");
2799 debug_printf(" file count quota = %d count = %d\n",
2800 ob->quota_filecount_value, mailbox_filecount);
2803 if (mailbox_size + (ob->quota_is_inclusive ? message_size:0) > ob->quota_value)
2806 if (!ob->quota_no_check)
2808 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2810 errno = ERRNO_EXIMQUOTA;
2812 else DEBUG(D_transport) debug_printf("mailbox quota exceeded but ignored\n");
2816 if (ob->quota_filecount_value > 0
2817 && mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2818 ob->quota_filecount_value)
2819 if(!ob->quota_filecount_no_check)
2821 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2823 errno = ERRNO_EXIMQUOTA;
2824 filecount_msg = US" filecount";
2826 else DEBUG(D_transport) if (ob->quota_filecount_no_check)
2827 debug_printf("mailbox file count quota exceeded but ignored\n");
2831 /* If we are writing in MBX format, what we actually do is to write the message
2832 to a temporary file, and then copy it to the real file once we know its size.
2833 This is the most straightforward way of getting the correct length in the
2834 separator line. So, what we do here is to save the real file descriptor, and
2835 replace it with one for a temporary file. The temporary file gets unlinked once
2836 opened, so that it goes away on closure. */
2839 if (yield == OK && ob->mbx_format)
2841 temp_file = tmpfile();
2842 if (temp_file == NULL)
2844 addr->basic_errno = errno;
2845 addr->message = US"while setting up temporary file";
2850 fd = fileno(temp_file);
2851 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2853 #endif /* SUPPORT_MBX */
2855 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2858 transport_count = 0;
2859 transport_newlines = 0;
2861 /* Write any configured prefix text first */
2863 if (yield == OK && ob->message_prefix != NULL && ob->message_prefix[0] != 0)
2865 uschar *prefix = expand_string(ob->message_prefix);
2868 errno = ERRNO_EXPANDFAIL;
2869 addr->transport_return = PANIC;
2870 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2871 "transport) failed", ob->message_prefix, tblock->name);
2874 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2877 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2878 various different values for batching are handled outside; if there is more
2879 than one address available here, all must be included. If any address is a
2880 file, use its parent in the RCPT TO. */
2882 if (yield == OK && ob->use_bsmtp)
2884 transport_count = 0;
2885 transport_newlines = 0;
2886 if (ob->use_crlf) cr = US"\r";
2887 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2891 transport_newlines++;
2892 for (address_item * a = addr; a != NULL; a = a->next)
2894 address_item *b = testflag(a, af_pfr) ? a->parent: a;
2895 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2896 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2897 { yield = DEFER; break; }
2898 transport_newlines++;
2900 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2903 transport_newlines++;
2907 /* Now the message itself. The options for transport_write_message were set up
2908 at initialization time. */
2912 transport_ctx tctx = {
2916 .check_string = ob->check_string,
2917 .escape_string = ob->escape_string,
2918 .options = ob->options | topt_not_socket
2920 if (!transport_write_message(&tctx, 0))
2924 /* Now a configured suffix. */
2926 if (yield == OK && ob->message_suffix != NULL && ob->message_suffix[0] != 0)
2928 uschar *suffix = expand_string(ob->message_suffix);
2931 errno = ERRNO_EXPANDFAIL;
2932 addr->transport_return = PANIC;
2933 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2934 "transport) failed", ob->message_suffix, tblock->name);
2937 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2940 /* If batch smtp, write the terminating dot. */
2942 if (yield == OK && ob->use_bsmtp ) {
2943 if(!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2944 else transport_newlines++;
2947 /* If MBX format is being used, all that writing was to the temporary file.
2948 However, if there was an earlier failure (Exim quota exceeded, for example),
2949 the temporary file won't have got opened - and no writing will have been done.
2950 If writing was OK, we restore the fd, and call a function that copies the
2951 message in MBX format into the real file. Otherwise use the temporary name in
2955 if (temp_file != NULL && ob->mbx_format)
2962 transport_count = 0; /* Reset transport count for actual write */
2963 /* No need to reset transport_newlines as we're just using a block copy
2964 * routine so the number won't be affected */
2965 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2967 else if (errno >= 0) dataname = US"temporary file";
2969 /* Preserve errno while closing the temporary file. */
2971 mbx_save_errno = errno;
2972 (void)fclose(temp_file);
2973 errno = mbx_save_errno;
2975 #endif /* SUPPORT_MBX */
2977 /* Force out the remaining data to check for any errors; some OS don't allow
2978 fsync() to be called for a FIFO. */
2980 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2982 /* Update message_size and message_linecount to the accurate count of bytes
2983 written, including added headers. Note; we subtract 1 from message_linecount as
2984 this variable doesn't count the new line between the header and the body of the
2987 message_size = transport_count;
2988 message_linecount = transport_newlines - 1;
2990 /* If using a maildir++ quota file, add this message's size to it, and
2991 close the file descriptor, except when the quota has been disabled because we
2992 are delivering into an uncounted folder. */
2994 #ifdef SUPPORT_MAILDIR
2997 if (yield == OK && maildirsize_fd >= 0)
2998 maildir_record_length(maildirsize_fd, message_size);
2999 maildir_save_errno = errno; /* Preserve errno while closing the file */
3000 if (maildirsize_fd >= 0)
3001 (void)close(maildirsize_fd);
3002 errno = maildir_save_errno;
3004 #endif /* SUPPORT_MAILDIR */
3006 /* If there is a quota warning threshold and we are have crossed it with this
3007 message, set the SPECIAL_WARN flag in the address, to cause a warning message
3010 if (!disable_quota && THRESHOLD_CHECK)
3012 off_t threshold = ob->quota_warn_threshold_value;
3013 if (ob->quota_warn_threshold_is_percent)
3014 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
3016 debug_printf("quota = " OFF_T_FMT
3017 " threshold = " OFF_T_FMT
3018 " old size = " OFF_T_FMT
3019 " message size = %d\n",
3020 ob->quota_value, threshold, mailbox_size,
3022 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
3023 addr->special_action = SPECIAL_WARN;
3025 /******* You might think that the test ought to be this:
3027 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
3028 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
3030 * (indeed, I was sent a patch with that in). However, it is possible to
3031 * have a warning threshold without actually imposing a quota, and I have
3032 * therefore kept Exim backwards compatible.
3037 /* Handle error while writing the file. Control should come here directly after
3038 the error, with the reason in errno. In the case of expansion failure in prefix
3039 or suffix, it will be ERRNO_EXPANDFAIL. */
3043 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
3045 /* Save the error number. If positive, it will ultimately cause a strerror()
3046 call to generate some text. */
3048 addr->basic_errno = errno;
3050 /* For system or Exim quota excession, or disk full, set more_errno to the
3051 time since the file was last read. If delivery was into a directory, the
3052 time since last read logic is not relevant, in general. However, for maildir
3053 deliveries we can approximate it by looking at the last modified time of the
3054 "new" subdirectory. Since Exim won't be adding new messages, a change to the
3055 "new" subdirectory implies that an MUA has moved a message from there to the
3058 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
3060 addr->more_errno = 0;
3061 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
3063 #ifdef SUPPORT_MAILDIR
3064 else if (mbformat == mbf_maildir)
3066 struct stat statbuf;
3067 if (Ustat("new", &statbuf) < 0)
3069 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
3070 "stat error %d for \"new\": %s\n", errno, strerror(errno));
3072 else /* Want a repeatable time when in test harness */
3074 addr->more_errno = f.running_in_test_harness ? 10 :
3075 (int)time(NULL) - statbuf.st_mtime;
3078 debug_printf("maildir: time since \"new\" directory modified = %s\n",
3079 readconf_printtime(addr->more_errno));
3081 #endif /* SUPPORT_MAILDIR */
3084 /* Handle system quota excession. Add an explanatory phrase for the error
3085 message, since some systems don't have special quota-excession errors,
3086 and on those that do, "quota" doesn't always mean anything to the user. */
3088 if (errno == errno_quota)
3091 addr->message = string_sprintf("mailbox is full "
3092 "(quota exceeded while writing to file %s)", filename);
3094 addr->message = string_sprintf("mailbox is full");
3096 addr->user_message = US"mailbox is full";
3097 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3099 isdirectory ? US"" : US": time since file read = ",
3100 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3103 /* Handle Exim's own quota-imposition */
3105 else if (errno == ERRNO_EXIMQUOTA)
3107 addr->message = string_sprintf("mailbox is full "
3108 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3110 addr->user_message = US"mailbox is full";
3111 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3112 filecount_msg, dataname,
3113 isdirectory ? US"" : US": time since file read = ",
3114 isdirectory ? US"" : readconf_printtime(addr->more_errno));
3117 /* Handle a process failure while writing via a filter; the return
3118 from child_close() is in more_errno. */
3120 else if (errno == ERRNO_FILTER_FAIL)
3123 addr->message = string_sprintf("transport filter process failed (%d) "
3124 "while writing to %s%s", addr->more_errno, dataname,
3125 (addr->more_errno == EX_EXECFAILED) ? ": unable to execute command" : "");
3128 /* Handle failure to expand header changes */
3130 else if (errno == ERRNO_CHHEADER_FAIL)
3134 string_sprintf("failed to expand headers_add or headers_remove while "
3135 "writing to %s: %s", dataname, expand_string_message);
3138 /* Handle failure to complete writing of a data block */
3140 else if (errno == ERRNO_WRITEINCOMPLETE)
3142 addr->message = string_sprintf("failed to write data block while "
3143 "writing to %s", dataname);
3146 /* Handle length mismatch on MBX copying */
3149 else if (errno == ERRNO_MBXLENGTH)
3151 addr->message = string_sprintf("length mismatch while copying MBX "
3152 "temporary file to %s", dataname);
3154 #endif /* SUPPORT_MBX */
3156 /* For other errors, a general-purpose explanation, if the message is
3159 else if (addr->message == NULL)
3160 addr->message = string_sprintf("error while writing to %s", dataname);
3162 /* For a file, reset the file size to what it was before we started, leaving
3163 the last modification time unchanged, so it will get reset also. All systems
3164 investigated so far have ftruncate(), whereas not all have the F_FREESP
3165 fcntl() call (BSDI & FreeBSD do not). */
3167 if (!isdirectory && ftruncate(fd, saved_size))
3168 DEBUG(D_transport) debug_printf("Error resetting file size\n");
3171 /* Handle successful writing - we want the modification time to be now for
3172 appended files. Remove the default backstop error number. For a directory, now
3173 is the time to rename the file with a unique name. As soon as such a name
3174 appears it may get used by another process, so we close the file first and
3175 check that all is well. */
3179 times.modtime = time(NULL);
3180 addr->basic_errno = 0;
3182 /* Handle the case of writing to a new file in a directory. This applies
3183 to all single-file formats - maildir, mailstore, and "smail format". */
3187 if (fstat(fd, &statbuf) < 0)
3189 addr->basic_errno = errno;
3190 addr->message = string_sprintf("while fstatting opened message file %s",
3195 else if (close(fd) < 0)
3197 addr->basic_errno = errno;
3198 addr->message = string_sprintf("close() error for %s",
3199 (ob->mailstore_format) ? dataname : filename);
3203 /* File is successfully written and closed. Arrange to rename it. For the
3204 different kinds of single-file delivery, some games can be played with the
3205 name. The message size is by this time set to the accurate value so that
3206 its value can be used in expansions. */
3210 uschar *renamename = newname;
3213 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3215 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3216 situation. The name is built by expanding the directory_file option, and
3217 we make the inode number available for use in this. The expansion was
3218 checked for syntactic validity above, before we wrote the file.
3220 We have to be careful here, in case the file name exists. (In the other
3221 cases, the names used are constructed to be unique.) The rename()
3222 function just replaces an existing file - we don't want that! So instead
3223 of calling rename(), we must use link() and unlink().
3225 In this case, if the link fails because of an existing file, we wait
3226 for one second and try the expansion again, to see if it produces a
3227 different value. Do this up to 5 times unless the name stops changing.
3228 This makes it possible to build values that are based on the time, and
3229 still cope with races from multiple simultaneous deliveries. */
3231 if (newname == NULL)
3234 uschar *old_renameleaf = US"";
3236 for (int i = 0; ; sleep(1), i++)
3238 deliver_inode = statbuf.st_ino;
3239 renameleaf = expand_string(ob->dirfilename);
3242 if (renameleaf == NULL)
3244 addr->transport_return = PANIC;
3245 addr->message = string_sprintf("Expansion of \"%s\" "
3246 "(directory_file for %s transport) failed: %s",
3247 ob->dirfilename, tblock->name, expand_string_message);
3251 renamename = string_sprintf("%s/%s", path, renameleaf);
3252 if (Ulink(filename, renamename) < 0)
3254 DEBUG(D_transport) debug_printf("link failed: %s\n",
3256 if (errno != EEXIST || i >= 4 ||
3257 Ustrcmp(renameleaf, old_renameleaf) == 0)
3259 addr->basic_errno = errno;
3260 addr->message = string_sprintf("while renaming %s as %s",
3261 filename, renamename);
3265 old_renameleaf = renameleaf;
3266 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3275 } /* re-expand loop */
3276 } /* not mailstore or maildir */
3278 /* For maildir and mailstore formats, the new name was created earlier,
3279 except that for maildir, there is the possibility of adding a "tag" on
3280 the end of the name by expanding the value of nametag. This usually
3281 includes a reference to the message size. The expansion of nametag was
3282 checked above, before the file was opened. It either succeeded, or
3283 provoked a soft failure. So any failure here can be treated as soft.
3284 Ignore non-printing characters and / and put a colon at the start if the
3285 first character is alphanumeric. */
3289 if (nametag != NULL)
3291 uschar *iptr = expand_string(nametag);
3294 uschar *etag = store_get(Ustrlen(iptr) + 2);
3295 uschar *optr = etag;
3298 if (mac_isgraph(*iptr) && *iptr != '/')
3300 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3306 renamename = string_sprintf("%s%s", newname, etag);
3310 /* Do the rename. If the name is too long and a tag exists, try again
3313 if (Urename(filename, renamename) < 0 &&
3314 (nametag == NULL || errno != ENAMETOOLONG ||
3315 (renamename = newname, Urename(filename, renamename) < 0)))
3317 addr->basic_errno = errno;
3318 addr->message = string_sprintf("while renaming %s as %s",
3319 filename, renamename);
3323 /* Rename succeeded */
3327 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3329 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3331 } /* maildir or mailstore */
3332 } /* successful write + close */
3334 } /* write success */
3337 /* For a file, restore the last access time (atime), and set the modification
3338 time as required - changed if write succeeded, unchanged if not. */
3340 if (!isdirectory) utime(CS filename, ×);
3342 /* Notify comsat if configured to do so. It only makes sense if the configured
3343 file is the one that the comsat daemon knows about. */
3345 if (ob->notify_comsat && yield == OK && deliver_localpart != NULL)
3346 notify_comsat(deliver_localpart, saved_size);
3348 /* Pass back the final return code in the address structure */
3351 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3352 yield, addr->basic_errno, addr->more_errno);
3354 addr->transport_return = yield;
3356 /* Close the file, which will release the fcntl lock. For a directory write it
3357 is closed above, except in cases of error which goto RETURN, when we also need
3358 to remove the original file(s). For MBX locking, if all has gone well, before
3359 closing the file, see if we can get an exclusive lock on it, in which case we
3360 can unlink the /tmp lock file before closing it. This is always a non-blocking
3361 lock; there's no need to wait if we can't get it. If everything has gone right
3362 but close fails, defer the message. Then unlink the lock file, if present. This
3363 point in the code is jumped to from a number of places when errors are
3364 detected, in order to get the file closed and the lock file tidied away. */
3369 if (mbx_lockfd >= 0)
3371 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3372 ob->use_flock, 0) >= 0)
3375 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3376 Uunlink(mbx_lockname);
3378 (void)close(mbx_lockfd);
3380 #endif /* SUPPORT_MBX */
3382 if (fd >= 0 && close(fd) < 0 && yield == OK)
3384 addr->basic_errno = errno;
3385 addr->message = string_sprintf("while closing %s", filename);
3386 addr->transport_return = DEFER;
3389 if (hd >= 0) Uunlink(lockname);
3391 /* We get here with isdirectory and filename set only in error situations. */
3393 if (isdirectory && filename != NULL)
3396 if (dataname != filename) Uunlink(dataname);
3399 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3400 file name relies on time + pid. We must not allow the process to finish until
3401 the clock has move on by at least one microsecond. Usually we expect this
3402 already to be the case, but machines keep getting faster... */
3404 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3406 /* A return of FALSE means that if there was an error, a common error was
3407 put in the first address of a batch. */
3412 #endif /*!MACRO_PREDEF*/
3413 /* End of transport/appendfile.c */