1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2016 */
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;
285 addrlist = addrlist; /* Keep picky compilers happy */
290 if (ob->expand_maildir_use_size_file)
291 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
292 US"`maildir_use_size_file` in transport", tblock->name);
294 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
297 for (i = 0; i < 5; i++)
301 uschar *which = NULL;
303 if (q == NULL) d = default_value;
307 uschar *s = expand_string(q);
311 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
312 "%s", q, tblock->name, expand_string_message);
313 return search_find_defer? DEFER : FAIL;
316 d = Ustrtod(s, &rest);
318 /* Handle following characters K, M, G, %, the latter being permitted
319 for quota_warn_threshold only. A threshold with no quota setting is
322 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
323 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
324 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
325 else if (*rest == '%' && i == 2)
327 if (ob->quota_value <= 0 && !ob->maildir_use_size_file) d = 0;
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) which = US"quota";
363 ob->quota_value = (off_t)d;
364 ob->quota_no_check = no_check;
365 q = ob->quota_filecount;
369 if (d >= 2.0*1024.0*1024.0*1024.0) which = US"quota_filecount";
370 ob->quota_filecount_value = (int)d;
371 ob->quota_filecount_no_check = no_check;
372 q = ob->quota_warn_threshold;
376 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
377 which = US"quota_warn_threshold";
378 ob->quota_warn_threshold_value = (off_t)d;
379 q = ob->mailbox_size_string;
380 default_value = -1.0;
384 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
385 which = US"mailbox_size";;
386 ob->mailbox_size_value = (off_t)d;
387 q = ob->mailbox_filecount_string;
391 if (d >= 2.0*1024.0*1024.0*1024.0) which = US"mailbox_filecount";
392 ob->mailbox_filecount_value = (int)d;
398 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
399 "%s transport", which, d, tblock->name);
409 /*************************************************
410 * Initialization entry point *
411 *************************************************/
413 /* Called for each instance, after its options have been read, to
414 enable consistency checks to be done, or anything else that needs
418 appendfile_transport_init(transport_instance *tblock)
420 appendfile_transport_options_block *ob =
421 (appendfile_transport_options_block *)(tblock->options_block);
423 /* Set up the setup entry point, to be called in the privileged state */
425 tblock->setup = appendfile_transport_setup;
427 /* Lock_retries must be greater than zero */
429 if (ob->lock_retries == 0) ob->lock_retries = 1;
431 /* Only one of a file name or directory name must be given. */
433 if (ob->filename != NULL && ob->dirname != NULL)
434 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
435 "only one of \"file\" or \"directory\" can be specified", tblock->name);
437 /* If a file name was specified, neither quota_filecount nor quota_directory
440 if (ob->filename != NULL)
442 if (ob->quota_filecount != NULL)
443 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
444 "quota_filecount must not be set without \"directory\"", tblock->name);
445 if (ob->quota_directory != NULL)
446 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
447 "quota_directory must not be set without \"directory\"", tblock->name);
450 /* The default locking depends on whether MBX is set or not. Change the
451 built-in default if none of the lock options has been explicitly set. At least
452 one form of locking is required in all cases, but mbx locking changes the
453 meaning of fcntl and flock locking. */
455 /* Not all operating systems provide flock(). For those that do, if flock is
456 requested, the default for fcntl is FALSE. */
461 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
462 "flock() support was not available in the operating system when this "
463 "binary was built", tblock->name);
464 #endif /* NO_FLOCK */
465 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
471 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
472 !ob->set_use_mbx_lock)
474 ob->use_lockfile = ob->use_flock = FALSE;
475 ob->use_mbx_lock = ob->use_fcntl = TRUE;
477 else if (ob->use_mbx_lock)
479 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
480 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
481 if (!ob->set_use_flock) ob->use_flock = FALSE;
482 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
485 #endif /* SUPPORT_MBX */
487 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
488 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
489 "no locking configured", tblock->name);
491 /* Unset timeouts for non-used locking types */
493 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
494 if (!ob->use_flock) ob->lock_flock_timeout = 0;
496 /* If a directory name was specified, only one of maildir or mailstore may be
497 specified, and if quota_filecount or quota_directory is given, quota must
500 if (ob->dirname != NULL)
502 if (ob->maildir_format && ob->mailstore_format)
503 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
504 "only one of maildir and mailstore may be specified", tblock->name);
505 if (ob->quota_filecount != NULL && ob->quota == NULL)
506 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
507 "quota must be set if quota_filecount is set", tblock->name);
508 if (ob->quota_directory != NULL && ob->quota == NULL)
509 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
510 "quota must be set if quota_directory is set", tblock->name);
513 /* If a fixed uid field is set, then a gid field must also be set. */
515 if (tblock->uid_set && !tblock->gid_set && tblock->expand_gid == NULL)
516 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
517 "user set without group for the %s transport", tblock->name);
519 /* If "create_file" is set, check that a valid option is given, and set the
522 if (ob->create_file_string != NULL)
525 if (Ustrcmp(ob->create_file_string, "anywhere") == 0) value = create_anywhere;
526 else if (Ustrcmp(ob->create_file_string, "belowhome") == 0) value =
528 else if (Ustrcmp(ob->create_file_string, "inhome") == 0)
529 value = create_inhome;
531 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
532 "invalid value given for \"file_create\" for the %s transport: %s",
533 tblock->name, ob->create_file_string);
534 ob->create_file = value;
537 /* If quota_warn_threshold is set, set up default for warn_message. It may
538 not be used if the actual threshold for a given delivery ends up as zero,
539 of if it's given as a percentage and there's no quota setting. */
541 if (ob->quota_warn_threshold != NULL)
543 if (tblock->warn_message == NULL) tblock->warn_message = US
544 "To: $local_part@$domain\n"
545 "Subject: Your mailbox\n\n"
546 "This message is automatically created by mail delivery software (Exim).\n\n"
547 "The size of your mailbox has exceeded a warning threshold that is\n"
548 "set by the system administrator.\n";
551 /* If batch SMTP is set, force the check and escape strings, and arrange that
552 headers are also escaped. */
556 ob->check_string = US".";
557 ob->escape_string = US"..";
558 ob->options |= topt_escape_headers;
561 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
562 insert default values for for the affixes and the check/escape strings. */
564 else if (ob->dirname == NULL && !ob->maildir_format && !ob->mailstore_format)
566 if (ob->message_prefix == NULL) ob->message_prefix =
567 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
568 if (ob->message_suffix == NULL) ob->message_suffix = US"\n";
569 if (ob->check_string == NULL) ob->check_string = US"From ";
570 if (ob->escape_string == NULL) ob->escape_string = US">From ";
574 /* Set up the bitwise options for transport_write_message from the various
575 driver options. Only one of body_only and headers_only can be set. */
578 (tblock->body_only? topt_no_headers : 0) |
579 (tblock->headers_only? topt_no_body : 0) |
580 (tblock->return_path_add? topt_add_return_path : 0) |
581 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
582 (tblock->envelope_to_add? topt_add_envelope_to : 0) |
583 ((ob->use_crlf || ob->mbx_format)? topt_use_crlf : 0);
588 /*************************************************
590 *************************************************/
592 /* The comsat daemon is the thing that provides asynchronous notification of
593 the arrival of local messages, if requested by the user by "biff y". It is a
594 BSD thing that uses a TCP/IP protocol for communication. A message consisting
595 of the text "user@offset" must be sent, where offset is the place in the
596 mailbox where new mail starts. There is no scope for telling it which file to
597 look at, which makes it a less than useful if mail is being delivered into a
598 non-standard place such as the user's home directory. In fact, it doesn't seem
599 to pay much attention to the offset.
603 offset offset in mailbox
609 notify_comsat(uschar *user, off_t offset)
616 DEBUG(D_transport) debug_printf("notify_comsat called\n");
618 sprintf(CS buffer, "%.200s@" OFF_T_FMT "\n", user, offset);
620 if ((sp = getservbyname("biff", "udp")) == NULL)
622 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
626 host.name = US"localhost";
630 /* This code is all set up to look up "localhost" and use all its addresses
631 until one succeeds. However, it appears that at least on some systems, comsat
632 doesn't listen on the ::1 address. So for the moment, just force the address to
633 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
634 can be changed. (But actually, comsat is probably dying out anyway.) */
637 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
639 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
644 host.address = US"127.0.0.1";
647 for (h = &host; h; h = h->next)
650 int host_af = Ustrchr(h->address, ':') != NULL ? AF_INET6 : AF_INET;
652 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
654 if ((sock = ip_socket(SOCK_DGRAM, host_af)) < 0) continue;
656 /* Connect never fails for a UDP socket, so don't set a timeout. */
658 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0, NULL);
659 rc = send(sock, buffer, Ustrlen(buffer) + 1, 0);
664 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
671 /*************************************************
672 * Check the format of a file *
673 *************************************************/
675 /* This function is called when file_format is set, to check that an existing
676 file has the right format. The format string contains text/transport pairs. The
677 string matching is literal. we just read big_buffer_size bytes, because this is
678 all about the first few bytes of a file.
682 tblock the transport block
683 addr the address block - for inserting error data
685 Returns: pointer to the required transport, or NULL
689 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
691 const uschar *format =
692 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
694 int len = read(cfd, data, sizeof(data));
698 DEBUG(D_transport) debug_printf("checking file format\n");
700 /* An empty file matches the current transport */
702 if (len == 0) return tblock;
704 /* Search the formats for a match */
706 while ((s = string_nextinlist(&format,&sep,big_buffer,big_buffer_size)))
708 int slen = Ustrlen(s);
709 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
710 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
714 transport_instance *tt;
715 for (tt = transports; tt; tt = tt->next)
716 if (Ustrcmp(tp, tt->name) == 0)
719 debug_printf("file format -> %s transport\n", tt->name);
722 addr->basic_errno = ERRNO_BADTRANSPORT;
723 addr->message = string_sprintf("%s transport (for %.*s format) not found",
729 /* Failed to find a match */
731 addr->basic_errno = ERRNO_FORMATUNKNOWN;
732 addr->message = US"mailbox file format unrecognized";
739 /*************************************************
740 * Check directory's files for quota *
741 *************************************************/
743 /* This function is called if quota is set for one of the delivery modes that
744 delivers into a specific directory. It scans the directory and stats all the
745 files in order to get a total size and count. This is an expensive thing to do,
746 but some people are prepared to bear the cost. Alternatively, if size_regex is
747 set, it is used as a regex to try to extract the size from the file name, a
748 strategy that some people use on maildir files on systems where the users have
751 The function is global, because it is also called from tf_maildir.c for maildir
752 folders (which should contain only regular files).
754 Note: Any problems can be written to debugging output, but cannot be written to
755 the log, because we are running as an unprivileged user here.
758 dirname the name of the directory
759 countptr where to add the file count (because this function recurses)
760 regex a compiled regex to get the size from a name
762 Returns: the sum of the sizes of the stattable files
763 zero if the directory cannot be opened
767 check_dir_size(uschar *dirname, int *countptr, const pcre *regex)
771 int count = *countptr;
775 dir = opendir(CS dirname);
776 if (dir == NULL) return 0;
778 while ((ent = readdir(dir)) != NULL)
780 uschar *name = US ent->d_name;
783 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
787 /* If there's a regex, try to find the size using it */
792 if (pcre_exec(regex, NULL, CS name, Ustrlen(name), 0, 0, ovector,6) >= 2)
795 off_t size = (off_t)Ustrtod(name + ovector[2], &endptr);
796 if (endptr == name + ovector[3])
800 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
806 debug_printf("check_dir_size: regex did not match %s\n", name);
809 /* No regex or no match for the regex, or captured non-digits */
811 if (!string_format(buffer, sizeof(buffer), "%s/%s", dirname, name))
814 debug_printf("check_dir_size: name too long: dir=%s name=%s\n", dirname,
819 if (Ustat(buffer, &statbuf) < 0)
822 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, buffer,
827 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
828 sum += statbuf.st_size;
829 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
830 sum += check_dir_size(buffer, &count, regex);
835 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
845 /*************************************************
846 * Apply a lock to a file descriptor *
847 *************************************************/
849 /* This function applies a lock to a file descriptor, using a blocking or
850 non-blocking lock, depending on the timeout value. It can apply either or
851 both of a fcntl() and a flock() lock. However, not all OS support flock();
852 for those that don't, the use_flock option cannot be set.
855 fd the file descriptor
856 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
857 fcntl() format); the flock() type is deduced if needed
858 dofcntl do fcntl() locking
859 fcntltime non-zero to use blocking fcntl()
860 doflock do flock() locking
861 flocktime non-zero to use blocking flock()
863 Returns: yield of the fcntl() or flock() call, with errno preserved;
864 sigalrm_seen set if there has been a timeout
868 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
873 struct flock lock_data;
874 lock_data.l_type = fcntltype;
875 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
877 sigalrm_seen = FALSE;
884 yield = fcntl(fd, F_SETLKW, &lock_data);
889 else yield = fcntl(fd, F_SETLK, &lock_data);
893 if (doflock && (yield >= 0))
895 int flocktype = (fcntltype == F_WRLCK)? LOCK_EX : LOCK_SH;
899 yield = flock(fd, flocktype);
904 else yield = flock(fd, flocktype | LOCK_NB);
906 #endif /* NO_FLOCK */
915 /*************************************************
916 * Copy message into MBX mailbox *
917 *************************************************/
919 /* This function is called when a message intended for a MBX mailbox has been
920 written to a temporary file. We can now get the size of the message and then
921 copy it in MBX format to the mailbox.
924 to_fd fd to write to (the real mailbox)
925 from_fd fd to read from (the temporary file)
926 saved_size current size of mailbox
928 Returns: OK if all went well, DEFER otherwise, with errno preserved
929 the number of bytes written are added to transport_count
930 by virtue of calling transport_write_block()
933 /* Values taken from c-client */
935 #define MBX_HDRSIZE 2048
936 #define MBX_NUSERFLAGS 30
939 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
944 transport_ctx tctx = {{0}};
948 /* If the current mailbox size is zero, write a header block */
954 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
955 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
956 (long int)time(NULL));
957 for (i = 0; i < MBX_NUSERFLAGS; i++)
958 sprintf (CS(s += Ustrlen(s)), "\015\012");
959 if (!transport_write_block (&tctx, deliver_out_buffer, MBX_HDRSIZE, FALSE))
963 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
965 /* Now construct the message's header from the time and the RFC822 file
966 size, including CRLFs, which is the size of the input (temporary) file. */
968 if (fstat(from_fd, &statbuf) < 0) return DEFER;
969 size = statbuf.st_size;
971 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
972 tod_stamp(tod_mbx), size, 0L, 0, 0);
973 used = Ustrlen(deliver_out_buffer);
975 /* Rewind the temporary file, and copy it over in chunks. */
977 if (lseek(from_fd, 0 , SEEK_SET) < 0) return DEFER;
981 int len = read(from_fd, deliver_out_buffer + used,
982 DELIVER_OUT_BUFFER_SIZE - used);
985 if (len == 0) errno = ERRNO_MBXLENGTH;
988 if (!transport_write_block(&tctx, deliver_out_buffer, used + len, FALSE))
996 #endif /* SUPPORT_MBX */
1000 /*************************************************
1001 * Check creation is permitted *
1002 *************************************************/
1004 /* This function checks whether a given file name is permitted to be created,
1005 as controlled by the create_file option. If no home directory is set, however,
1006 we can't do any tests.
1009 filename the file name
1010 create_file the ob->create_file option
1012 Returns: TRUE if creation is permitted
1016 check_creation(uschar *filename, int create_file)
1020 if (deliver_home != NULL && create_file != create_anywhere)
1022 int len = Ustrlen(deliver_home);
1023 uschar *file = filename;
1025 while (file[0] == '/' && file[1] == '/') file++;
1026 if (Ustrncmp(file, deliver_home, len) != 0 || file[len] != '/' ||
1027 ( Ustrchr(file+len+2, '/') != NULL &&
1029 create_file != create_belowhome ||
1030 Ustrstr(file+len, "/../") != NULL
1035 /* If yield is TRUE, the file name starts with the home directory, and does
1036 not contain any instances of "/../" in the "belowhome" case. However, it may
1037 still contain symbolic links. We can check for this by making use of
1038 realpath(), which most Unixes seem to have (but make it possible to cut this
1039 out). We can't just use realpath() on the whole file name, because we know
1040 the file itself doesn't exist, and intermediate directories may also not
1041 exist. What we want to know is the real path of the longest existing part of
1042 the path. That must match the home directory's beginning, whichever is the
1046 if (yield && create_file == create_belowhome)
1048 uschar *slash, *next;
1050 for (slash = Ustrrchr(file, '/'); /* There is known to be one */
1051 rp == NULL && slash > file; /* Stop if reached beginning */
1055 rp = US realpath(CS file, CS big_buffer);
1056 next = Ustrrchr(file, '/');
1060 /* If rp == NULL it means that none of the relevant directories exist.
1061 This is not a problem here - it means that no symbolic links can exist,
1062 which is all we are worried about. Otherwise, we must compare it
1063 against the start of the home directory. However, that may itself
1064 contain symbolic links, so we have to "realpath" it as well, if
1069 uschar hdbuffer[PATH_MAX+1];
1070 uschar *rph = deliver_home;
1071 int rlen = Ustrlen(big_buffer);
1073 rp = US realpath(CS deliver_home, CS hdbuffer);
1080 if (rlen > len) rlen = len;
1081 if (Ustrncmp(rph, big_buffer, rlen) != 0)
1084 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
1085 big_buffer, deliver_home);
1089 #endif /* NO_REALPATH */
1097 /*************************************************
1098 * Main entry point *
1099 *************************************************/
1101 /* See local README for general interface details. This transport always
1102 returns FALSE, indicating that the status which has been placed in the first
1103 address should be copied to any other addresses in a batch.
1105 Appendfile delivery is tricky and has led to various security problems in other
1106 mailers. The logic used here is therefore laid out in some detail. When this
1107 function is called, we are running in a subprocess which has had its gid and
1108 uid set to the appropriate values. Therefore, we cannot write directly to the
1109 exim logs. Any errors must be handled by setting appropriate return codes.
1110 Note that the default setting for addr->transport_return is DEFER, so it need
1111 not be set unless some other value is required.
1113 The code below calls geteuid() rather than getuid() to get the current uid
1114 because in weird configurations not running setuid root there may be a
1115 difference. In the standard configuration, where setuid() has been used in the
1116 delivery process, there will be no difference between the uid and the euid.
1118 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1119 alias expansion. Otherwise, there must be a configured file name or
1122 The following items apply in the case when a file name (as opposed to a
1123 directory name) is given, that is, when appending to a single file:
1125 (2f) Expand the file name.
1127 (3f) If the file name is /dev/null, return success (optimization).
1129 (4f) If the file_format options is set, open the file for reading, and check
1130 that the bytes at the start of the file match one of the given strings.
1131 If the check indicates a transport other than the current one should be
1132 used, pass control to that other transport. Otherwise continue. An empty
1133 or non-existent file matches the current transport. The file is closed
1136 (5f) If a lock file is required, create it (see extensive separate comments
1137 below about the algorithm for doing this). It is important to do this
1138 before opening the mailbox if NFS is in use.
1140 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1141 details of any symbolic link.
1143 (7f) If the file already exists:
1145 Check the owner and group if necessary, and defer if they are wrong.
1147 If it is a symbolic link AND the allow_symlink option is set (NOT the
1148 default), go back to (6f) but this time use stat() instead of lstat().
1150 If it's not a regular file (or FIFO when permitted), defer delivery.
1152 Check permissions. If the required permissions are *less* than the
1153 existing ones, or supplied by the address (often by the user via filter),
1154 chmod() the file. Otherwise, defer.
1156 Save the inode number.
1158 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1160 If open fails because the file does not exist, go to (6f); on any other
1163 Check the inode number hasn't changed - I realize this isn't perfect (an
1164 inode can be reused) but it's cheap and will catch some of the races.
1166 Check it's still a regular file (or FIFO if permitted).
1168 Check that the owner and permissions haven't changed.
1170 If file_format is set, check that the file still matches the format for
1171 the current transport. If not, defer delivery.
1173 (8f) If file does not exist initially:
1175 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1176 this is via a symbolic link (only possible if allow_symlinks is set), in
1177 which case don't use O_EXCL, as it doesn't work.
1179 If open fails because the file already exists, go to (6f). To avoid
1180 looping for ever in a situation where the file is continuously being
1181 created and deleted, all of this happens inside a loop that operates
1182 lock_retries times and includes the fcntl and flock locking. If the
1183 loop completes without the file getting opened, defer and request
1184 freezing, because something really weird is happening.
1186 If open fails for any other reason, defer for subsequent delivery except
1187 when this is a file delivery resulting from an alias or forward expansion
1188 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1189 most likely a user rather than a configuration error.
1191 (9f) We now have the file checked and open for writing. If so configured, lock
1192 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1193 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1194 still fails, give up and defer delivery.
1196 (10f)Save the access time (for subsequent restoration) and the size of the
1197 file, for comsat and for re-setting if delivery fails in the middle -
1198 e.g. for quota exceeded.
1200 The following items apply in the case when a directory name is given:
1202 (2d) Create a new file in the directory using a temporary name, by opening for
1203 writing and with O_CREAT. If maildir format is being used, the file
1204 is created in a temporary subdirectory with a prescribed name. If
1205 mailstore format is being used, the envelope file is first created with a
1206 temporary name, then the data file.
1208 The following items apply in all cases:
1210 (11) We now have the file open for writing, and locked if it was given as a
1211 file name. Write the message and flush the file, unless there is a setting
1212 of the local quota option, in which case we can check for its excession
1213 without doing any writing.
1215 In the case of MBX format mailboxes, the message is first written to a
1216 temporary file, in order to get its correct length. This is then copied to
1217 the real file, preceded by an MBX header.
1219 If there is a quota error on writing, defer the address. Timeout logic
1220 will determine for how long retries are attempted. We restore the mailbox
1221 to its original length if it's a single file. There doesn't seem to be a
1222 uniform error code for quota excession (it even differs between SunOS4
1223 and some versions of SunOS5) so a system-dependent macro called
1224 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1227 For any other error (most commonly disk full), do the same.
1229 The following applies after appending to a file:
1231 (12f)Restore the atime; notify_comsat if required; close the file (which
1232 unlocks it if it was locked). Delete the lock file if it exists.
1234 The following applies after writing a unique file in a directory:
1236 (12d)For maildir format, rename the file into the new directory. For mailstore
1237 format, rename the envelope file to its correct name. Otherwise, generate
1238 a unique name from the directory_file option, and rename to that, possibly
1239 trying a few times if the file exists and re-expanding the name gives a
1242 This transport yields FAIL only when a file name is generated by an alias or
1243 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1244 All other failures return DEFER (in addr->transport_return). */
1248 appendfile_transport_entry(
1249 transport_instance *tblock, /* data for this instantiation */
1250 address_item *addr) /* address we are working on */
1252 appendfile_transport_options_block *ob =
1253 (appendfile_transport_options_block *)(tblock->options_block);
1254 struct stat statbuf;
1255 uschar *fdname = NULL;
1256 uschar *filename = NULL;
1257 uschar *hitchname = NULL;
1258 uschar *dataname = NULL;
1259 uschar *lockname = NULL;
1260 uschar *newname = NULL;
1261 uschar *nametag = NULL;
1263 uschar *filecount_msg = US"";
1265 struct utimbuf times;
1266 struct timeval msg_tv;
1267 BOOL disable_quota = FALSE;
1268 BOOL isdirectory = FALSE;
1269 BOOL isfifo = FALSE;
1270 BOOL wait_for_tick = FALSE;
1271 uid_t uid = geteuid(); /* See note above */
1272 gid_t gid = getegid();
1274 int mode = (addr->mode > 0)? addr->mode : ob->mode;
1275 off_t saved_size = -1;
1276 off_t mailbox_size = ob->mailbox_size_value;
1277 int mailbox_filecount = ob->mailbox_filecount_value;
1285 int mbx_lockfd = -1;
1286 uschar mbx_lockname[40];
1287 FILE *temp_file = NULL;
1288 #endif /* SUPPORT_MBX */
1290 #ifdef SUPPORT_MAILDIR
1291 int maildirsize_fd = -1; /* fd for maildirsize file */
1292 int maildir_save_errno;
1296 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1298 /* An "address_file" or "address_directory" transport is used to deliver to
1299 files specified via .forward or an alias file. Prior to release 4.20, the
1300 "file" and "directory" options were ignored in this case. This has been changed
1301 to allow the redirection data to specify what is in effect a folder, whose
1302 location is determined by the options on the transport.
1304 Compatibility with the case when neither option is set is retained by forcing a
1305 value for the file or directory name. A directory delivery is assumed if the
1306 last character of the path from the router is '/'.
1308 The file path is in the local part of the address, but not in the $local_part
1309 variable (that holds the parent local part). It is, however, in the
1310 $address_file variable. Below, we update the local part in the address if it
1311 changes by expansion, so that the final path ends up in the log. */
1313 if (testflag(addr, af_file) &&
1314 ob->filename == NULL &&
1315 ob->dirname == NULL)
1317 fdname = US"$address_file";
1318 if (address_file[Ustrlen(address_file)-1] == '/' ||
1319 ob->maildir_format ||
1320 ob->mailstore_format)
1324 /* Handle (a) an "address file" delivery where "file" or "directory" is
1325 explicitly set and (b) a non-address_file delivery, where one of "file" or
1326 "directory" must be set; initialization ensures that they are not both set. */
1330 fdname = ob->filename;
1333 fdname = ob->dirname;
1338 addr->transport_return = PANIC;
1339 addr->message = string_sprintf("Mandatory file or directory option "
1340 "missing from %s transport", tblock->name);
1345 /* Maildir and mailstore require a directory */
1347 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1349 addr->transport_return = PANIC;
1350 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1351 "to be specified for the %s transport",
1352 ob->maildir_format? "dir" : "store", tblock->name);
1356 path = expand_string(fdname);
1360 addr->transport_return = PANIC;
1361 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1362 "name for %s transport) failed: %s", fdname, tblock->name,
1363 expand_string_message);
1369 addr->message = string_sprintf("appendfile: file or directory name "
1370 "\"%s\" is not absolute", path);
1371 addr->basic_errno = ERRNO_NOTABSOLUTE;
1375 /* For a file delivery, make sure the local part in the address(es) is updated
1376 to the true local part. */
1378 if (testflag(addr, af_file))
1380 address_item *addr2;
1381 for (addr2 = addr; addr2 != NULL; addr2 = addr2->next)
1382 addr2->local_part = string_copy(path);
1385 /* The available mailbox formats depend on whether it is a directory or a file
1391 #ifdef SUPPORT_MAILDIR
1392 (ob->maildir_format)? mbf_maildir :
1394 #ifdef SUPPORT_MAILSTORE
1395 (ob->mailstore_format)? mbf_mailstore :
1403 (ob->mbx_format)? mbf_mbx :
1410 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1412 " warning=" OFF_T_FMT "%s\n"
1413 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1414 "maildir_use_size_file=%s\n",
1415 mode, ob->notify_comsat, ob->quota_value,
1416 ob->quota_no_check? " (no_check)" : "",
1417 ob->quota_filecount_no_check? " (no_check_filecount)" : "",
1418 ob->quota_warn_threshold_value,
1419 ob->quota_warn_threshold_is_percent? "%" : "",
1420 isdirectory? "directory" : "file",
1421 path, mailbox_formats[mbformat],
1422 (ob->message_prefix == NULL)? US"null" : string_printing(ob->message_prefix),
1423 (ob->message_suffix == NULL)? US"null" : string_printing(ob->message_suffix),
1424 (ob->maildir_use_size_file)? "yes" : "no");
1426 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1427 ob->use_lockfile? "lockfile " : "",
1428 ob->use_mbx_lock? "mbx locking (" : "",
1429 ob->use_fcntl? "fcntl " : "",
1430 ob->use_flock? "flock" : "",
1431 ob->use_mbx_lock? ")" : "");
1434 /* If the -N option is set, can't do any more. */
1439 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1441 addr->transport_return = OK;
1445 /* Handle the case of a file name. If the file name is /dev/null, we can save
1446 ourselves some effort and just give a success return right away. */
1450 BOOL use_lstat = TRUE;
1451 BOOL file_opened = FALSE;
1452 BOOL allow_creation_here = TRUE;
1454 if (Ustrcmp(path, "/dev/null") == 0)
1456 addr->transport_return = OK;
1460 /* Set the name of the file to be opened, and the file to which the data
1461 is written, and find out if we are permitted to create a non-existent file. */
1463 dataname = filename = path;
1464 allow_creation_here = check_creation(filename, ob->create_file);
1466 /* If ob->create_directory is set, attempt to create the directories in
1467 which this mailbox lives, but only if we are permitted to create the file
1468 itself. We know we are dealing with an absolute path, because this was
1471 if (ob->create_directory && allow_creation_here)
1473 uschar *p = Ustrrchr(path, '/');
1475 if (!directory_make(NULL, path, ob->dirmode, FALSE))
1477 addr->basic_errno = errno;
1479 string_sprintf("failed to create directories for %s: %s", path,
1481 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1487 /* If file_format is set we must check that any existing file matches one of
1488 the configured formats by checking the bytes it starts with. A match then
1489 indicates a specific transport - if it is not this one, pass control to it.
1490 Otherwise carry on here. An empty or non-existent file matches the current
1491 transport. We don't need to distinguish between non-existence and other open
1492 failures because if an existing file fails to open here, it will also fail
1493 again later when O_RDWR is used. */
1495 if (ob->file_format != NULL)
1497 int cfd = Uopen(path, O_RDONLY, 0);
1500 transport_instance *tt = check_file_format(cfd, tblock, addr);
1503 /* If another transport is indicated, call it and return; if no transport
1504 was found, just return - the error data will have been set up.*/
1510 set_process_info("delivering %s to %s using %s", message_id,
1511 addr->local_part, tt->name);
1512 debug_print_string(tt->debug_string);
1513 addr->transport = tt;
1514 (tt->info->code)(tt, addr);
1521 /* The locking of mailbox files is worse than the naming of cats, which is
1522 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1523 three different names, so several different styles of locking are used.
1525 Research in other programs that lock mailboxes shows that there is no
1526 universally standard method. Having mailboxes NFS-mounted on the system that
1527 is delivering mail is not the best thing, but people do run like this,
1528 and so the code must do its best to cope.
1530 Three different locking mechanisms are supported. The initialization function
1531 checks that at least one is configured.
1535 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1536 will work over NFS. Only after that is done do we actually open the mailbox
1537 and apply locks to it (if configured).
1539 Originally, Exim got the file opened before doing anything about locking.
1540 However, a very occasional problem was observed on Solaris 2 when delivering
1541 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1542 gets remembered at open time. If another process on another host (that's
1543 important) has the file open and locked and writes to it and then releases
1544 the lock while the first process is waiting to get the lock, the first
1545 process may fail to write at the new end point of the file - despite the very
1546 definite statement about O_APPEND in the man page for write(). Experiments
1547 have reproduced this problem, but I do not know any way of forcing a host to
1548 update its attribute cache for an open NFS file. It would be nice if it did
1549 so when a lock was taken out, but this does not seem to happen. Anyway, to
1550 reduce the risk of this problem happening, we now create the lock file
1551 (if configured) *before* opening the mailbox. That will prevent two different
1552 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1553 however, but Pine at least seems to operate in the same way.
1555 Lockfiles should normally be used when NFS is involved, because of the above
1558 The logic for creating the lock file is:
1560 . The name of the lock file is <mailbox-name>.lock
1562 . First, create a "hitching post" name by adding the primary host name,
1563 current time and pid to the lock file name. This should be unique.
1565 . Create the hitching post file using WRONLY + CREAT + EXCL.
1567 . If that fails EACCES, we assume it means that the user is unable to create
1568 files in the mail spool directory. Some installations might operate in this
1569 manner, so there is a configuration option to allow this state not to be an
1570 error - we proceed to lock using fcntl only, after the file is open.
1572 . Otherwise, an error causes a deferment of the address.
1574 . Hard link the hitching post to the lock file name.
1576 . If the link succeeds, we have successfully created the lock file. Simply
1577 close and unlink the hitching post file.
1579 . If the link does not succeed, proceed as follows:
1581 o Fstat the hitching post file, and then close and unlink it.
1583 o Now examine the stat data. If the number of links to the file is exactly
1584 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1585 the return never made it back, so the link() function gave a failure
1588 . This method allows for the lock file to be created by some other process
1589 right up to the moment of the attempt to hard link it, and is also robust
1590 against NFS server crash-reboots, which would probably result in timeouts
1591 in the middle of link().
1593 . System crashes may cause lock files to get left lying around, and some means
1594 of flushing them is required. The approach of writing a pid (used by smail
1595 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1596 timeout, which seems a better approach. Since any program that writes to a
1597 mailbox using a lock file should complete its task very quickly, Pine
1598 removes lock files that are older than 5 minutes. We allow the value to be
1599 configurable on the transport.
1603 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1604 mailbox once it is open. This is done by default with a non-blocking lock.
1605 Failures to lock cause retries after a sleep, but only for a certain number
1606 of tries. A blocking lock is deliberately not used so that we don't hold the
1607 mailbox open. This minimizes the possibility of the NFS problem described
1608 under LOCK FILES above, if for some reason NFS deliveries are happening
1609 without lock files. However, the use of a non-blocking lock and sleep, though
1610 the safest approach, does not give the best performance on very busy systems.
1611 A blocking lock plus timeout does better. Therefore Exim has an option to
1612 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1613 enables the use of blocking fcntl() calls.
1617 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1618 same manner as for fcntl locking above. No-blocking/timeout is also set as
1619 above in lock_flock_timeout. Not all operating systems provide or support
1620 flock(). For those that don't (as determined by the definition of LOCK_SH in
1621 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1622 is implemented (not precisely) on top of fcntl(), which means there's no
1623 point in actually using it.
1627 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1628 then the rules used for locking in c-client are used. Exim takes out a shared
1629 lock on the mailbox file, and an exclusive lock on the file whose name is
1630 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1631 any other MBX client from getting an exclusive lock on it and expunging it.
1632 It also stops any other MBX client from unlinking the /tmp lock when it has
1635 The exclusive lock on the /tmp file prevents any other MBX client from
1636 updating the mailbox in any way. When writing is finished, if an exclusive
1637 lock on the mailbox can be obtained, indicating there are no current sharers,
1638 the /tmp file is unlinked.
1640 MBX locking can use either fcntl() or flock() locking. If neither
1641 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1642 The calls for getting these locks are by default non-blocking, as for non-mbx
1643 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1644 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1645 probably makes sense to set timeouts for any MBX deliveries. */
1648 /* Build a lock file if configured to do so - the existence of a lock
1649 file is subsequently checked by looking for a non-negative value of the
1650 file descriptor hd - even though the file is no longer open. */
1652 if (ob->use_lockfile)
1654 /* cf. exim_lock.c */
1655 lockname = string_sprintf("%s.lock", filename);
1656 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1657 (unsigned int)(time(NULL)), (unsigned int)getpid());
1659 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1662 /* Lock file creation retry loop */
1664 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1667 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1671 addr->basic_errno = errno;
1673 string_sprintf("creating lock file hitching post %s "
1674 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1675 (long int)getegid());
1679 /* Attempt to hitch the hitching post to the lock file. If link()
1680 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1681 file, and get rid of the hitching post. If the number of links was 2,
1682 the link was created, despite the failure of link(). If the hitch was
1683 not successful, try again, having unlinked the lock file if it is too
1686 There's a version of Linux (2.0.27) which doesn't update its local cache
1687 of the inode after link() by default - which many think is a bug - but
1688 if the link succeeds, this code will be OK. It just won't work in the
1689 case when link() fails after having actually created the link. The Linux
1690 NFS person is fixing this; a temporary patch is available if anyone is
1691 sufficiently worried. */
1693 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1696 if (rc != 0 && statbuf.st_nlink != 2)
1698 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1699 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1701 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1704 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1708 DEBUG(D_transport) debug_printf("lock file created\n");
1712 /* Check for too many tries at creating the lock file */
1714 if (i >= ob->lock_retries)
1716 addr->basic_errno = ERRNO_LOCKFAILED;
1717 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1724 /* We now have to get the file open. First, stat() it and act on existence or
1725 non-existence. This is in a loop to handle the case of a file's being created
1726 or deleted as we watch, and also to handle retries when the locking fails.
1727 Rather than holding the file open while waiting for the fcntl() and/or
1728 flock() lock, we close and do the whole thing again. This should be safer,
1729 especially for NFS files, which might get altered from other hosts, making
1730 their cached sizes incorrect.
1732 With the default settings, no symlinks are permitted, but there is an option
1733 to permit symlinks for those sysadmins that know what they are doing.
1734 Shudder. However, insist that the initial symlink is owned by the right user.
1735 Thus lstat() is used initially; if a symlink is discovered, the loop is
1736 repeated such that stat() is used, to look at the end file. */
1738 for (i = 0; i < ob->lock_retries; i++)
1740 int sleep_before_retry = TRUE;
1741 file_opened = FALSE;
1743 if((use_lstat? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1745 /* Let's hope that failure to stat (other than non-existence) is a
1748 if (errno != ENOENT)
1750 addr->basic_errno = errno;
1751 addr->message = string_sprintf("attempting to stat mailbox %s",
1756 /* File does not exist. If it is required to pre-exist this state is an
1759 if (ob->file_must_exist)
1761 addr->basic_errno = errno;
1762 addr->message = string_sprintf("mailbox %s does not exist, "
1763 "but file_must_exist is set", filename);
1767 /* If not permitted to create this file because it isn't in or below
1768 the home directory, generate an error. */
1770 if (!allow_creation_here)
1772 addr->basic_errno = ERRNO_BADCREATE;
1773 addr->message = string_sprintf("mailbox %s does not exist, "
1774 "but creation outside the home directory is not permitted",
1779 /* Attempt to create and open the file. If open fails because of
1780 pre-existence, go round the loop again. For any other error, defer the
1781 address, except for an alias or forward generated file name with EPERM,
1782 ENOENT, or EACCES, as those are most likely to be user errors rather
1783 than Exim config errors. When a symbolic link is permitted and points
1784 to a non-existent file, we get here with use_lstat = FALSE. In this case
1785 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1786 consistency and because MBX locking requires it in order to be able to
1787 get a shared lock. */
1789 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1790 (use_lstat? O_EXCL : 0), mode);
1793 if (errno == EEXIST) continue;
1794 addr->basic_errno = errno;
1795 addr->message = string_sprintf("while creating mailbox %s",
1797 if (testflag(addr, af_file) &&
1798 (errno == EPERM || errno == ENOENT || errno == EACCES))
1799 addr->transport_return = FAIL;
1803 /* We have successfully created and opened the file. Ensure that the group
1804 and the mode are correct. */
1806 if(Uchown(filename, uid, gid) || Uchmod(filename, mode))
1808 addr->basic_errno = errno;
1809 addr->message = string_sprintf("while setting perms on mailbox %s",
1811 addr->transport_return = FAIL;
1817 /* The file already exists. Test its type, ownership, and permissions, and
1818 save the inode for checking later. If symlinks are permitted (not the
1819 default or recommended state) it may be a symlink that already exists.
1820 Check its ownership and then look for the file at the end of the link(s).
1821 This at least prevents one user creating a symlink for another user in
1822 a sticky directory. */
1826 int oldmode = (int)statbuf.st_mode;
1827 ino_t inode = statbuf.st_ino;
1828 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1830 isfifo = FALSE; /* In case things are changing */
1832 /* Check owner if required - the default. */
1834 if (ob->check_owner && statbuf.st_uid != uid)
1836 addr->basic_errno = ERRNO_BADUGID;
1837 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1838 "(%ld != %ld)", filename,
1839 islink? " (symlink)" : "",
1840 (long int)(statbuf.st_uid), (long int)uid);
1844 /* Group is checked only if check_group is set. */
1846 if (ob->check_group && statbuf.st_gid != gid)
1848 addr->basic_errno = ERRNO_BADUGID;
1849 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1850 filename, islink? " (symlink)" : "", statbuf.st_gid, gid);
1854 /* Just in case this is a sticky-bit mail directory, we don't want
1855 users to be able to create hard links to other users' files. */
1857 if (statbuf.st_nlink != 1)
1859 addr->basic_errno = ERRNO_NOTREGULAR;
1860 addr->message = string_sprintf("mailbox %s%s has too many links (%d)",
1861 filename, islink? " (symlink)" : "", statbuf.st_nlink);
1866 /* If symlinks are permitted (not recommended), the lstat() above will
1867 have found the symlink. Its ownership has just been checked; go round
1868 the loop again, using stat() instead of lstat(). That will never yield a
1871 if (islink && ob->allow_symlink)
1874 i--; /* Don't count this time round */
1878 /* An actual file exists. Check that it is a regular file, or FIFO
1881 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1883 else if ((oldmode & S_IFMT) != S_IFREG)
1885 addr->basic_errno = ERRNO_NOTREGULAR;
1886 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1887 filename, ob->allow_fifo? " or named pipe" : "");
1891 /* If the mode is not what it would be for a newly created file, change
1892 the permissions if the mode is supplied for the address. Otherwise,
1893 reduce but do not extend the permissions. If the newly created
1894 permissions are greater than the existing permissions, don't change
1895 things when the mode is not from the address. */
1897 if ((oldmode = (oldmode & 07777)) != mode)
1899 int diffs = oldmode ^ mode;
1900 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1902 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1903 if (Uchmod(filename, mode) < 0)
1905 addr->basic_errno = errno;
1906 addr->message = string_sprintf("attempting to chmod mailbox %s",
1913 /* Mode not from address, and newly-created permissions are greater
1914 than existing permissions. Default is to complain, but it can be
1915 configured to go ahead and try to deliver anyway if that's what
1916 the administration wants. */
1918 else if (ob->mode_fail_narrower)
1920 addr->basic_errno = ERRNO_BADMODE;
1921 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1922 "(%o expected)", filename, oldmode, mode);
1927 /* We are happy with the existing file. Open it, and then do further
1928 tests to ensure that it is the same file that we were just looking at.
1929 If the file does not now exist, restart this loop, going back to using
1930 lstat again. For an NFS error, just defer; other opening errors are
1931 more serious. The file is opened RDWR so that its format can be checked,
1932 and also MBX locking requires the use of a shared (read) lock. However,
1933 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1934 reading the pipe. */
1936 fd = Uopen(filename, isfifo? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1940 if (errno == ENOENT)
1945 addr->basic_errno = errno;
1948 addr->message = string_sprintf("while opening named pipe %s "
1949 "(could mean no process is reading it)", filename);
1951 else if (errno != EWOULDBLOCK)
1953 addr->message = string_sprintf("while opening mailbox %s", filename);
1958 /* This fstat really shouldn't fail, as we have an open file! There's a
1959 dilemma here. We use fstat in order to be sure we are peering at the file
1960 we have got open. However, that won't tell us if the file was reached
1961 via a symbolic link. We checked this above, but there is a race exposure
1962 if the link was created between the previous lstat and the open. However,
1963 it would have to be created with the same inode in order to pass the
1964 check below. If ob->allow_symlink is set, causing the use of stat rather
1965 than lstat above, symbolic links may be there anyway, and the checking is
1968 if (fstat(fd, &statbuf) < 0)
1970 addr->basic_errno = errno;
1971 addr->message = string_sprintf("attempting to stat open mailbox %s",
1976 /* Check the inode; this is isn't a perfect check, but gives some
1979 if (inode != statbuf.st_ino)
1981 addr->basic_errno = ERRNO_INODECHANGED;
1982 addr->message = string_sprintf("opened mailbox %s inode number changed "
1983 "from %d to %ld", filename, inode, statbuf.st_ino);
1984 addr->special_action = SPECIAL_FREEZE;
1988 /* Check it's still a regular file or FIFO, and the uid, gid, and
1989 permissions have not changed. */
1991 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1992 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1994 addr->basic_errno = ERRNO_NOTREGULAR;
1996 string_sprintf("opened mailbox %s is no longer a %s", filename,
1997 isfifo? "named pipe" : "regular file");
1998 addr->special_action = SPECIAL_FREEZE;
2002 if ((ob->check_owner && statbuf.st_uid != uid) ||
2003 (ob->check_group && statbuf.st_gid != gid))
2005 addr->basic_errno = ERRNO_BADUGID;
2007 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
2008 addr->special_action = SPECIAL_FREEZE;
2012 if ((statbuf.st_mode & 07777) != oldmode)
2014 addr->basic_errno = ERRNO_BADMODE;
2015 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
2016 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
2017 addr->special_action = SPECIAL_FREEZE;
2021 /* If file_format is set, check that the format of the file has not
2022 changed. Error data is set by the testing function. */
2024 if (ob->file_format != NULL &&
2025 check_file_format(fd, tblock, addr) != tblock)
2027 addr->message = US"open mailbox has changed format";
2031 /* The file is OK. Carry on to do the locking. */
2034 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
2035 locking rules if configured to do so. If a lock file is also required, it
2036 was created above and hd was left >= 0. At least one form of locking is
2037 required by the initialization function. If locking fails here, close the
2038 file and go round the loop all over again, after waiting for a bit, unless
2039 blocking locking was used. */
2042 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
2043 sleep_before_retry = FALSE;
2045 /* Simple fcntl() and/or flock() locking */
2047 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
2049 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2050 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
2053 /* MBX locking rules */
2056 else if (ob->use_mbx_lock)
2059 struct stat lstatbuf, statbuf2;
2060 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2061 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
2062 fstat(fd, &statbuf) >= 0)
2064 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
2065 (long)statbuf.st_ino);
2068 * 2010-05-29: SECURITY
2069 * Dan Rosenberg reported the presence of a race-condition in the
2070 * original code here. Beware that many systems still allow symlinks
2071 * to be followed in /tmp so an attacker can create a symlink pointing
2072 * elsewhere between a stat and an open, which we should avoid
2075 * It's unfortunate that we can't just use all the heavily debugged
2076 * locking from above.
2078 * Also: remember to mirror changes into exim_lock.c */
2080 /* first leave the old pre-check in place, it provides better
2081 * diagnostics for common cases */
2082 if (Ulstat(mbx_lockname, &statbuf) >= 0)
2084 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
2086 addr->basic_errno = ERRNO_LOCKFAILED;
2087 addr->message = string_sprintf("symbolic link on MBX lock file %s",
2091 if (statbuf.st_nlink > 1)
2093 addr->basic_errno = ERRNO_LOCKFAILED;
2094 addr->message = string_sprintf("hard link to MBX lock file %s",
2100 /* If we could just declare "we must be the ones who create this
2101 * file" then a hitching post in a subdir would work, since a
2102 * subdir directly in /tmp/ which we create wouldn't follow links
2103 * but this isn't our locking logic, so we can't safely change the
2104 * file existence rules. */
2106 /* On systems which support O_NOFOLLOW, it's the easiest and most
2107 * obviously correct security fix */
2108 mbx_tmp_oflags = O_RDWR | O_CREAT;
2110 mbx_tmp_oflags |= O_NOFOLLOW;
2112 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
2115 addr->basic_errno = ERRNO_LOCKFAILED;
2116 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2117 mbx_lockname, strerror(errno));
2121 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2123 addr->basic_errno = ERRNO_LOCKFAILED;
2124 addr->message = string_sprintf("attempting to lstat open MBX "
2125 "lock file %s: %s", mbx_lockname, strerror(errno));
2128 if (fstat(mbx_lockfd, &statbuf2) < 0)
2130 addr->basic_errno = ERRNO_LOCKFAILED;
2131 addr->message = string_sprintf("attempting to stat fd of open MBX "
2132 "lock file %s: %s", mbx_lockname, strerror(errno));
2138 * statbuf: if exists, is file which existed prior to opening the
2139 * lockfile, might have been replaced since then
2140 * statbuf2: result of stat'ing the open fd, is what was actually
2142 * lstatbuf: result of lstat'ing the filename immediately after
2143 * the open but there's a race condition again between
2144 * those two steps: before open, symlink to foo, after
2145 * open but before lstat have one of:
2146 * * was no symlink, so is the opened file
2147 * (we created it, no messing possible after that point)
2149 * * symlink elsewhere
2150 * * hardlink elsewhere
2152 * Don't want to compare to device of /tmp because some modern systems
2153 * have regressed to having /tmp be the safe actual filesystem as
2154 * valuable data, so is mostly worthless, unless we assume that *only*
2155 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2156 * for further consideration.
2157 * No point in doing a readlink on the lockfile as that will always be
2158 * at a different point in time from when we open it, so tells us
2159 * nothing; attempts to clean up and delete after ourselves would risk
2160 * deleting a *third* filename.
2162 if ((statbuf2.st_nlink > 1) ||
2163 (lstatbuf.st_nlink > 1) ||
2164 (!S_ISREG(lstatbuf.st_mode)) ||
2165 (lstatbuf.st_dev != statbuf2.st_dev) ||
2166 (lstatbuf.st_ino != statbuf2.st_ino))
2168 addr->basic_errno = ERRNO_LOCKFAILED;
2169 addr->message = string_sprintf("RACE CONDITION detected: "
2170 "mismatch post-initial-checks between \"%s\" and opened "
2171 "fd lead us to abort!", mbx_lockname);
2175 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2177 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2178 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2180 struct stat ostatbuf;
2182 /* This tests for a specific race condition. Ensure that we still
2183 have the same file. */
2185 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2186 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2187 statbuf.st_dev == ostatbuf.st_dev &&
2188 statbuf.st_ino == ostatbuf.st_ino)
2190 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2191 "between creation and locking\n", mbx_lockname);
2194 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2196 (void)close(mbx_lockfd);
2201 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2202 filename, strerror(errno));
2205 #endif /* SUPPORT_MBX */
2207 else break; /* No on-file locking required; break the open/lock loop */
2210 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2214 use_lstat = TRUE; /* Reset to use lstat first */
2217 /* If a blocking call timed out, break the retry loop if the total time
2218 so far is not less than than retries * interval. Use the larger of the
2219 flock() and fcntl() timeouts. */
2222 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2223 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2224 ob->lock_retries * ob->lock_interval)
2225 i = ob->lock_retries;
2227 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2228 flock() that caused the problem. */
2230 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2233 /* Test for exceeding the maximum number of tries. Either the file remains
2234 locked, or, if we haven't got it open, something is terribly wrong... */
2236 if (i >= ob->lock_retries)
2240 addr->basic_errno = ERRNO_EXISTRACE;
2241 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2242 addr->special_action = SPECIAL_FREEZE;
2246 addr->basic_errno = ERRNO_LOCKFAILED;
2247 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2253 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2255 /* Save access time (for subsequent restoration), modification time (for
2256 restoration if updating fails), size of file (for comsat and for re-setting if
2257 delivery fails in the middle - e.g. for quota exceeded). */
2259 if (fstat(fd, &statbuf) < 0)
2261 addr->basic_errno = errno;
2262 addr->message = string_sprintf("while fstatting opened mailbox %s",
2267 times.actime = statbuf.st_atime;
2268 times.modtime = statbuf.st_mtime;
2269 saved_size = statbuf.st_size;
2270 if (mailbox_size < 0) mailbox_size = saved_size;
2271 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2274 /* Prepare for writing to a new file (as opposed to appending to an old one).
2275 There are several different formats, but there is preliminary stuff concerned
2276 with quotas that applies to all of them. Finding the current size by directory
2277 scanning is expensive; for maildirs some fudges have been invented:
2279 (1) A regex can be used to extract a file size from its name;
2280 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2286 uschar *check_path = path; /* Default quota check path */
2287 const pcre *regex = NULL; /* Regex for file size from file name */
2289 if (!check_creation(string_sprintf("%s/any", path), ob->create_file))
2291 addr->basic_errno = ERRNO_BADCREATE;
2292 addr->message = string_sprintf("tried to create file in %s, but "
2293 "file creation outside the home directory is not permitted", path);
2297 #ifdef SUPPORT_MAILDIR
2298 /* For a maildir delivery, ensure that all the relevant directories exist,
2299 and a maildirfolder file if necessary. */
2301 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2302 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2304 #endif /* SUPPORT_MAILDIR */
2306 /* If we are going to do a quota check, of if maildir_use_size_file is set
2307 for a maildir delivery, compile the regular expression if there is one. We
2308 may also need to adjust the path that is used. We need to do this for
2309 maildir_use_size_file even if the quota is unset, because we still want to
2310 create the file. When maildir support is not compiled,
2311 ob->maildir_use_size_file is always FALSE. */
2313 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2315 const uschar *error;
2318 /* Compile the regex if there is one. */
2320 if (ob->quota_size_regex != NULL)
2322 regex = pcre_compile(CS ob->quota_size_regex, PCRE_COPT,
2323 (const char **)&error, &offset, NULL);
2326 addr->message = string_sprintf("appendfile: regular expression "
2327 "error: %s at offset %d while compiling %s", error, offset,
2328 ob->quota_size_regex);
2331 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2332 ob->quota_size_regex);
2335 /* Use an explicitly configured directory if set */
2337 if (ob->quota_directory != NULL)
2339 check_path = expand_string(ob->quota_directory);
2340 if (check_path == NULL)
2342 addr->transport_return = PANIC;
2343 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2344 "name for %s transport) failed: %s", ob->quota_directory,
2345 tblock->name, expand_string_message);
2349 if (check_path[0] != '/')
2351 addr->message = string_sprintf("appendfile: quota_directory name "
2352 "\"%s\" is not absolute", check_path);
2353 addr->basic_errno = ERRNO_NOTABSOLUTE;
2358 #ifdef SUPPORT_MAILDIR
2359 /* Otherwise, if we are handling a maildir delivery, and the directory
2360 contains a file called maildirfolder, this is a maildir++ feature telling
2361 us that this is a sub-directory of the real inbox. We should therefore do
2362 the quota check on the parent directory. Beware of the special case when
2363 the directory name itself ends in a slash. */
2365 else if (mbformat == mbf_maildir)
2367 struct stat statbuf;
2368 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2370 uschar *new_check_path = string_copy(check_path);
2371 uschar *slash = Ustrrchr(new_check_path, '/');
2377 slash = Ustrrchr(new_check_path, '/');
2382 check_path = new_check_path;
2383 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2384 "quota check directory changed to %s\n", check_path);
2389 #endif /* SUPPORT_MAILDIR */
2392 /* If we are using maildirsize files, we need to ensure that such a file
2393 exists and, if necessary, recalculate its contents. As a byproduct of this,
2394 we obtain the current size of the maildir. If no quota is to be enforced
2395 (ob->quota_value == 0), we still need the size if a threshold check will
2398 Another regular expression is used to determine which directories inside the
2399 maildir are going to be counted. */
2401 #ifdef SUPPORT_MAILDIR
2402 if (ob->maildir_use_size_file)
2404 const pcre *dir_regex = NULL;
2405 const uschar *error;
2408 if (ob->maildir_dir_regex != NULL)
2410 int check_path_len = Ustrlen(check_path);
2412 dir_regex = pcre_compile(CS ob->maildir_dir_regex, PCRE_COPT,
2413 (const char **)&error, &offset, NULL);
2414 if (dir_regex == NULL)
2416 addr->message = string_sprintf("appendfile: regular expression "
2417 "error: %s at offset %d while compiling %s", error, offset,
2418 ob->maildir_dir_regex);
2423 debug_printf("using regex for maildir directory selection: %s\n",
2424 ob->maildir_dir_regex);
2426 /* Check to see if we are delivering into an ignored directory, that is,
2427 if the delivery path starts with the quota check path, and the rest
2428 of the deliver path matches the regex; if so, set a flag to disable quota
2429 checking and maildirsize updating. */
2431 if (Ustrncmp(path, check_path, check_path_len) == 0)
2433 uschar *s = path + check_path_len;
2434 while (*s == '/') s++;
2435 s = (*s == 0)? US "new" : string_sprintf("%s/new", s);
2436 if (pcre_exec(dir_regex, NULL, CS s, Ustrlen(s), 0, 0, NULL, 0) < 0)
2438 disable_quota = TRUE;
2439 DEBUG(D_transport) debug_printf("delivery directory does not match "
2440 "maildir_quota_directory_regex: disabling quota\n");
2445 /* Quota enforcement; create and check the file. There is some discussion
2446 about whether this should happen if the quota is unset. At present, Exim
2447 always creates the file. If we ever want to change this, uncomment
2448 appropriate lines below, possibly doing a check on some option. */
2450 /* if (???? || ob->quota_value > 0) */
2457 maildirsize_fd = maildir_ensure_sizefile(check_path, ob, regex, dir_regex,
2460 if (maildirsize_fd == -1)
2462 addr->basic_errno = errno;
2463 addr->message = string_sprintf("while opening or reading "
2464 "%s/maildirsize", check_path);
2467 /* can also return -2, which means that the file was removed because of
2468 raciness; but in this case, the size & filecount will still have been
2471 if (mailbox_size < 0) mailbox_size = size;
2472 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2475 /* No quota enforcement; ensure file does *not* exist; calculate size if
2480 * time_t old_latest;
2481 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2482 * if (THRESHOLD_CHECK)
2483 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2484 * regex, dir_regex, FALSE);
2489 #endif /* SUPPORT_MAILDIR */
2491 /* Otherwise if we are going to do a quota check later on, and the mailbox
2492 size is not set, find the current size of the mailbox. Ditto for the file
2493 count. Note that ob->quota_filecount_value cannot be set without
2494 ob->quota_value being set. */
2496 if (!disable_quota &&
2497 (ob->quota_value > 0 || THRESHOLD_CHECK) &&
2498 (mailbox_size < 0 ||
2499 (mailbox_filecount < 0 && ob->quota_filecount_value > 0)))
2504 debug_printf("quota checks on directory %s\n", check_path);
2505 size = check_dir_size(check_path, &filecount, regex);
2506 if (mailbox_size < 0) mailbox_size = size;
2507 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2510 /* Handle the case of creating a unique file in a given directory (not in
2511 maildir or mailstore format - this is how smail did it). A temporary name is
2512 used to create the file. Later, when it is written, the name is changed to a
2513 unique one. There is no need to lock the file. An attempt is made to create
2514 the directory if it does not exist. */
2516 if (mbformat == mbf_smail)
2519 debug_printf("delivering to new file in %s\n", path);
2520 filename = dataname =
2521 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2522 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2523 if (fd < 0 && /* failed to open, and */
2524 (errno != ENOENT || /* either not non-exist */
2525 !ob->create_directory || /* or not allowed to make */
2526 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2527 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2529 addr->basic_errno = errno;
2530 addr->message = string_sprintf("while creating file %s", filename);
2535 #ifdef SUPPORT_MAILDIR
2537 /* Handle the case of a unique file in maildir format. The file is written to
2538 the tmp subdirectory, with a prescribed form of name. */
2540 else if (mbformat == mbf_maildir)
2543 debug_printf("delivering in maildir format in %s\n", path);
2545 nametag = ob->maildir_tag;
2547 /* Check that nametag expands successfully; a hard failure causes a panic
2548 return. The actual expansion for use happens again later, when
2549 $message_size is accurately known. */
2551 if (nametag != NULL && expand_string(nametag) == NULL &&
2552 !expand_string_forcedfail)
2554 addr->transport_return = PANIC;
2555 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2556 "for %s transport) failed: %s", nametag, tblock->name,
2557 expand_string_message);
2561 /* We ensured the existence of all the relevant directories above. Attempt
2562 to open the temporary file a limited number of times. I think this rather
2563 scary-looking for statement is actually OK. If open succeeds, the loop is
2564 broken; if not, there is a test on the value of i. Get the time again
2565 afresh each time round the loop. Its value goes into a variable that is
2566 checked at the end, to make sure we don't release this process until the
2567 clock has ticked. */
2573 (void)gettimeofday(&msg_tv, NULL);
2574 basename = string_sprintf(TIME_T_FMT ".H%luP%lu.%s",
2575 msg_tv.tv_sec, msg_tv.tv_usec, getpid(), primary_hostname);
2577 filename = dataname = string_sprintf("tmp/%s", basename);
2578 newname = string_sprintf("new/%s", basename);
2580 if (Ustat(filename, &statbuf) == 0)
2582 else if (errno == ENOENT)
2584 fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode);
2586 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2587 filename, strerror(errno));
2590 /* Too many retries - give up */
2592 if (i >= ob->maildir_retries)
2594 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2595 filename, i, (i == 1)? "y" : "ies");
2596 addr->basic_errno = errno;
2597 if (errno == errno_quota || errno == ENOSPC)
2598 addr->user_message = US"mailbox is full";
2602 /* Open or stat failed but we haven't tried too many times yet. */
2607 /* Note that we have to ensure the clock has ticked before leaving */
2609 wait_for_tick = TRUE;
2611 /* Why are these here? Put in because they are present in the non-maildir
2612 directory case above. */
2614 if(Uchown(filename, uid, gid) || Uchmod(filename, mode))
2616 addr->basic_errno = errno;
2617 addr->message = string_sprintf("while setting perms on maildir %s",
2623 #endif /* SUPPORT_MAILDIR */
2625 #ifdef SUPPORT_MAILSTORE
2627 /* Handle the case of a unique file in mailstore format. First write the
2628 envelope to a temporary file, then open the main file. The unique base name
2629 for the files consists of the message id plus the pid of this delivery
2635 address_item *taddr;
2636 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2637 string_base62((long int)getpid()));
2640 debug_printf("delivering in mailstore format in %s\n", path);
2642 filename = string_sprintf("%s.tmp", mailstore_basename);
2643 newname = string_sprintf("%s.env", mailstore_basename);
2644 dataname = string_sprintf("%s.msg", mailstore_basename);
2646 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2647 if (fd < 0 && /* failed to open, and */
2648 (errno != ENOENT || /* either not non-exist */
2649 !ob->create_directory || /* or not allowed to make */
2650 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2651 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2653 addr->basic_errno = errno;
2654 addr->message = string_sprintf("while creating file %s", filename);
2658 /* Why are these here? Put in because they are present in the non-maildir
2659 directory case above. */
2661 if(Uchown(filename, uid, gid) || Uchmod(filename, mode))
2663 addr->basic_errno = errno;
2664 addr->message = string_sprintf("while setting perms on file %s",
2669 /* Built a C stream from the open file descriptor. */
2671 if ((env_file = fdopen(fd, "wb")) == NULL)
2673 addr->basic_errno = errno;
2674 addr->transport_return = PANIC;
2675 addr->message = string_sprintf("fdopen of %s ("
2676 "for %s transport) failed", filename, tblock->name);
2682 /* Write the envelope file, then close it. */
2684 if (ob->mailstore_prefix != NULL)
2686 uschar *s = expand_string(ob->mailstore_prefix);
2689 if (!expand_string_forcedfail)
2691 addr->transport_return = PANIC;
2692 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2693 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2694 tblock->name, expand_string_message);
2695 (void)fclose(env_file);
2703 fprintf(env_file, "%s", CS s);
2704 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2708 fprintf(env_file, "%s\n", sender_address);
2710 for (taddr = addr; taddr!= NULL; taddr = taddr->next)
2711 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2713 if (ob->mailstore_suffix != NULL)
2715 uschar *s = expand_string(ob->mailstore_suffix);
2718 if (!expand_string_forcedfail)
2720 addr->transport_return = PANIC;
2721 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2722 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2723 tblock->name, expand_string_message);
2724 (void)fclose(env_file);
2732 fprintf(env_file, "%s", CS s);
2733 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2737 if (fclose(env_file) != 0)
2739 addr->basic_errno = errno;
2740 addr->message = string_sprintf("while closing %s", filename);
2745 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2747 /* Now open the data file, and ensure that it has the correct ownership and
2750 fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode);
2753 addr->basic_errno = errno;
2754 addr->message = string_sprintf("while creating file %s", dataname);
2758 if(Uchown(dataname, uid, gid) || Uchmod(dataname, mode))
2760 addr->basic_errno = errno;
2761 addr->message = string_sprintf("while setting perms on file %s",
2767 #endif /* SUPPORT_MAILSTORE */
2770 /* In all cases of writing to a new file, ensure that the file which is
2771 going to be renamed has the correct ownership and mode. */
2773 if(Uchown(filename, uid, gid) || Uchmod(filename, mode))
2775 addr->basic_errno = errno;
2776 addr->message = string_sprintf("while setting perms on file %s",
2783 /* At last we can write the message to the file, preceded by any configured
2784 prefix line, and followed by any configured suffix line. If there are any
2785 writing errors, we must defer. */
2787 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2792 /* If there is a local quota setting, check that we are not going to exceed it
2793 with this message if quota_is_inclusive is set; if it is not set, the check
2794 is for the mailbox already being over quota (i.e. the current message is not
2795 included in the check). */
2797 if (!disable_quota && ob->quota_value > 0)
2801 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2802 " this message = %d (%sincluded)\n",
2803 ob->quota_value, mailbox_size, message_size,
2804 ob->quota_is_inclusive? "" : "not ");
2805 debug_printf(" file count quota = %d count = %d\n",
2806 ob->quota_filecount_value, mailbox_filecount);
2809 if (mailbox_size + (ob->quota_is_inclusive? message_size:0) > ob->quota_value)
2812 if (!ob->quota_no_check)
2814 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2816 errno = ERRNO_EXIMQUOTA;
2818 else DEBUG(D_transport) debug_printf("mailbox quota exceeded but ignored\n");
2822 if (ob->quota_filecount_value > 0
2823 && mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2824 ob->quota_filecount_value)
2825 if(!ob->quota_filecount_no_check)
2827 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2829 errno = ERRNO_EXIMQUOTA;
2830 filecount_msg = US" filecount";
2832 else DEBUG(D_transport) if (ob->quota_filecount_no_check)
2833 debug_printf("mailbox file count quota exceeded but ignored\n");
2837 /* If we are writing in MBX format, what we actually do is to write the message
2838 to a temporary file, and then copy it to the real file once we know its size.
2839 This is the most straightforward way of getting the correct length in the
2840 separator line. So, what we do here is to save the real file descriptor, and
2841 replace it with one for a temporary file. The temporary file gets unlinked once
2842 opened, so that it goes away on closure. */
2845 if (yield == OK && ob->mbx_format)
2847 temp_file = tmpfile();
2848 if (temp_file == NULL)
2850 addr->basic_errno = errno;
2851 addr->message = US"while setting up temporary file";
2856 fd = fileno(temp_file);
2857 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2859 #endif /* SUPPORT_MBX */
2861 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2864 transport_count = 0;
2865 transport_newlines = 0;
2867 /* Write any configured prefix text first */
2869 if (yield == OK && ob->message_prefix != NULL && ob->message_prefix[0] != 0)
2871 uschar *prefix = expand_string(ob->message_prefix);
2874 errno = ERRNO_EXPANDFAIL;
2875 addr->transport_return = PANIC;
2876 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2877 "transport) failed", ob->message_prefix, tblock->name);
2880 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2883 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2884 various different values for batching are handled outside; if there is more
2885 than one address available here, all must be included. If any address is a
2886 file, use its parent in the RCPT TO. */
2888 if (yield == OK && ob->use_bsmtp)
2890 transport_count = 0;
2891 transport_newlines = 0;
2892 if (ob->use_crlf) cr = US"\r";
2893 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2898 transport_newlines++;
2899 for (a = addr; a != NULL; a = a->next)
2901 address_item *b = testflag(a, af_pfr)? a->parent: a;
2902 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2903 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2904 { yield = DEFER; break; }
2905 transport_newlines++;
2907 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2910 transport_newlines++;
2914 /* Now the message itself. The options for transport_write_message were set up
2915 at initialization time. */
2919 transport_ctx tctx = {
2927 if (!transport_write_message(&tctx, 0))
2931 /* Now a configured suffix. */
2933 if (yield == OK && ob->message_suffix != NULL && ob->message_suffix[0] != 0)
2935 uschar *suffix = expand_string(ob->message_suffix);
2938 errno = ERRNO_EXPANDFAIL;
2939 addr->transport_return = PANIC;
2940 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2941 "transport) failed", ob->message_suffix, tblock->name);
2944 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2947 /* If batch smtp, write the terminating dot. */
2949 if (yield == OK && ob->use_bsmtp ) {
2950 if(!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2951 else transport_newlines++;
2954 /* If MBX format is being used, all that writing was to the temporary file.
2955 However, if there was an earlier failure (Exim quota exceeded, for example),
2956 the temporary file won't have got opened - and no writing will have been done.
2957 If writing was OK, we restore the fd, and call a function that copies the
2958 message in MBX format into the real file. Otherwise use the temporary name in
2962 if (temp_file != NULL && ob->mbx_format)
2969 transport_count = 0; /* Reset transport count for actual write */
2970 /* No need to reset transport_newlines as we're just using a block copy
2971 * routine so the number won't be affected */
2972 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2974 else if (errno >= 0) dataname = US"temporary file";
2976 /* Preserve errno while closing the temporary file. */
2978 mbx_save_errno = errno;
2979 (void)fclose(temp_file);
2980 errno = mbx_save_errno;
2982 #endif /* SUPPORT_MBX */
2984 /* Force out the remaining data to check for any errors; some OS don't allow
2985 fsync() to be called for a FIFO. */
2987 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2989 /* Update message_size and message_linecount to the accurate count of bytes
2990 written, including added headers. Note; we subtract 1 from message_linecount as
2991 this variable doesn't count the new line between the header and the body of the
2994 message_size = transport_count;
2995 message_linecount = transport_newlines - 1;
2997 /* If using a maildir++ quota file, add this message's size to it, and
2998 close the file descriptor, except when the quota has been disabled because we
2999 are delivering into an uncounted folder. */
3001 #ifdef SUPPORT_MAILDIR
3004 if (yield == OK && maildirsize_fd >= 0)
3005 maildir_record_length(maildirsize_fd, message_size);
3006 maildir_save_errno = errno; /* Preserve errno while closing the file */
3007 if (maildirsize_fd >= 0)
3008 (void)close(maildirsize_fd);
3009 errno = maildir_save_errno;
3011 #endif /* SUPPORT_MAILDIR */
3013 /* If there is a quota warning threshold and we are have crossed it with this
3014 message, set the SPECIAL_WARN flag in the address, to cause a warning message
3017 if (!disable_quota && THRESHOLD_CHECK)
3019 off_t threshold = ob->quota_warn_threshold_value;
3020 if (ob->quota_warn_threshold_is_percent)
3021 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
3023 debug_printf("quota = " OFF_T_FMT
3024 " threshold = " OFF_T_FMT
3025 " old size = " OFF_T_FMT
3026 " message size = %d\n",
3027 ob->quota_value, threshold, mailbox_size,
3029 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
3030 addr->special_action = SPECIAL_WARN;
3032 /******* You might think that the test ought to be this:
3034 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
3035 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
3037 * (indeed, I was sent a patch with that in). However, it is possible to
3038 * have a warning threshold without actually imposing a quota, and I have
3039 * therefore kept Exim backwards compatible.
3044 /* Handle error while writing the file. Control should come here directly after
3045 the error, with the reason in errno. In the case of expansion failure in prefix
3046 or suffix, it will be ERRNO_EXPANDFAIL. */
3050 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
3052 /* Save the error number. If positive, it will ultimately cause a strerror()
3053 call to generate some text. */
3055 addr->basic_errno = errno;
3057 /* For system or Exim quota excession, or disk full, set more_errno to the
3058 time since the file was last read. If delivery was into a directory, the
3059 time since last read logic is not relevant, in general. However, for maildir
3060 deliveries we can approximate it by looking at the last modified time of the
3061 "new" subdirectory. Since Exim won't be adding new messages, a change to the
3062 "new" subdirectory implies that an MUA has moved a message from there to the
3065 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
3067 addr->more_errno = 0;
3068 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
3070 #ifdef SUPPORT_MAILDIR
3071 else if (mbformat == mbf_maildir)
3073 struct stat statbuf;
3074 if (Ustat("new", &statbuf) < 0)
3076 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
3077 "stat error %d for \"new\": %s\n", errno, strerror(errno));
3079 else /* Want a repeatable time when in test harness */
3081 addr->more_errno = running_in_test_harness? 10 :
3082 (int)time(NULL) - statbuf.st_mtime;
3085 debug_printf("maildir: time since \"new\" directory modified = %s\n",
3086 readconf_printtime(addr->more_errno));
3088 #endif /* SUPPORT_MAILDIR */
3091 /* Handle system quota excession. Add an explanatory phrase for the error
3092 message, since some systems don't have special quota-excession errors,
3093 and on those that do, "quota" doesn't always mean anything to the user. */
3095 if (errno == errno_quota)
3098 addr->message = string_sprintf("mailbox is full "
3099 "(quota exceeded while writing to file %s)", filename);
3101 addr->message = string_sprintf("mailbox is full");
3103 addr->user_message = US"mailbox is full";
3104 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3106 isdirectory? US"" : US": time since file read = ",
3107 isdirectory? US"" : readconf_printtime(addr->more_errno));
3110 /* Handle Exim's own quota-imposition */
3112 else if (errno == ERRNO_EXIMQUOTA)
3114 addr->message = string_sprintf("mailbox is full "
3115 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3117 addr->user_message = US"mailbox is full";
3118 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3119 filecount_msg, dataname,
3120 isdirectory? US"" : US": time since file read = ",
3121 isdirectory? US"" : readconf_printtime(addr->more_errno));
3124 /* Handle a process failure while writing via a filter; the return
3125 from child_close() is in more_errno. */
3127 else if (errno == ERRNO_FILTER_FAIL)
3130 addr->message = string_sprintf("transport filter process failed (%d) "
3131 "while writing to %s%s", addr->more_errno, dataname,
3132 (addr->more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
3135 /* Handle failure to expand header changes */
3137 else if (errno == ERRNO_CHHEADER_FAIL)
3141 string_sprintf("failed to expand headers_add or headers_remove while "
3142 "writing to %s: %s", dataname, expand_string_message);
3145 /* Handle failure to complete writing of a data block */
3147 else if (errno == ERRNO_WRITEINCOMPLETE)
3149 addr->message = string_sprintf("failed to write data block while "
3150 "writing to %s", dataname);
3153 /* Handle length mismatch on MBX copying */
3156 else if (errno == ERRNO_MBXLENGTH)
3158 addr->message = string_sprintf("length mismatch while copying MBX "
3159 "temporary file to %s", dataname);
3161 #endif /* SUPPORT_MBX */
3163 /* For other errors, a general-purpose explanation, if the message is
3166 else if (addr->message == NULL)
3167 addr->message = string_sprintf("error while writing to %s", dataname);
3169 /* For a file, reset the file size to what it was before we started, leaving
3170 the last modification time unchanged, so it will get reset also. All systems
3171 investigated so far have ftruncate(), whereas not all have the F_FREESP
3172 fcntl() call (BSDI & FreeBSD do not). */
3174 if (!isdirectory && ftruncate(fd, saved_size))
3175 DEBUG(D_transport) debug_printf("Error resetting file size\n");
3178 /* Handle successful writing - we want the modification time to be now for
3179 appended files. Remove the default backstop error number. For a directory, now
3180 is the time to rename the file with a unique name. As soon as such a name
3181 appears it may get used by another process, so we close the file first and
3182 check that all is well. */
3186 times.modtime = time(NULL);
3187 addr->basic_errno = 0;
3189 /* Handle the case of writing to a new file in a directory. This applies
3190 to all single-file formats - maildir, mailstore, and "smail format". */
3194 if (fstat(fd, &statbuf) < 0)
3196 addr->basic_errno = errno;
3197 addr->message = string_sprintf("while fstatting opened message file %s",
3202 else if (close(fd) < 0)
3204 addr->basic_errno = errno;
3205 addr->message = string_sprintf("close() error for %s",
3206 (ob->mailstore_format)? dataname : filename);
3210 /* File is successfully written and closed. Arrange to rename it. For the
3211 different kinds of single-file delivery, some games can be played with the
3212 name. The message size is by this time set to the accurate value so that
3213 its value can be used in expansions. */
3217 uschar *renamename = newname;
3220 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3222 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3223 situation. The name is built by expanding the directory_file option, and
3224 we make the inode number available for use in this. The expansion was
3225 checked for syntactic validity above, before we wrote the file.
3227 We have to be careful here, in case the file name exists. (In the other
3228 cases, the names used are constructed to be unique.) The rename()
3229 function just replaces an existing file - we don't want that! So instead
3230 of calling rename(), we must use link() and unlink().
3232 In this case, if the link fails because of an existing file, we wait
3233 for one second and try the expansion again, to see if it produces a
3234 different value. Do this up to 5 times unless the name stops changing.
3235 This makes it possible to build values that are based on the time, and
3236 still cope with races from multiple simultaneous deliveries. */
3238 if (newname == NULL)
3242 uschar *old_renameleaf = US"";
3244 for (i = 0; ; sleep(1), i++)
3246 deliver_inode = statbuf.st_ino;
3247 renameleaf = expand_string(ob->dirfilename);
3250 if (renameleaf == NULL)
3252 addr->transport_return = PANIC;
3253 addr->message = string_sprintf("Expansion of \"%s\" "
3254 "(directory_file for %s transport) failed: %s",
3255 ob->dirfilename, tblock->name, expand_string_message);
3259 renamename = string_sprintf("%s/%s", path, renameleaf);
3260 if (Ulink(filename, renamename) < 0)
3262 DEBUG(D_transport) debug_printf("link failed: %s\n",
3264 if (errno != EEXIST || i >= 4 ||
3265 Ustrcmp(renameleaf, old_renameleaf) == 0)
3267 addr->basic_errno = errno;
3268 addr->message = string_sprintf("while renaming %s as %s",
3269 filename, renamename);
3273 old_renameleaf = renameleaf;
3274 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3283 } /* re-expand loop */
3284 } /* not mailstore or maildir */
3286 /* For maildir and mailstore formats, the new name was created earlier,
3287 except that for maildir, there is the possibility of adding a "tag" on
3288 the end of the name by expanding the value of nametag. This usually
3289 includes a reference to the message size. The expansion of nametag was
3290 checked above, before the file was opened. It either succeeded, or
3291 provoked a soft failure. So any failure here can be treated as soft.
3292 Ignore non-printing characters and / and put a colon at the start if the
3293 first character is alphanumeric. */
3297 if (nametag != NULL)
3299 uschar *iptr = expand_string(nametag);
3302 uschar *etag = store_get(Ustrlen(iptr) + 2);
3303 uschar *optr = etag;
3306 if (mac_isgraph(*iptr) && *iptr != '/')
3308 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3314 renamename = string_sprintf("%s%s", newname, etag);
3318 /* Do the rename. If the name is too long and a tag exists, try again
3321 if (Urename(filename, renamename) < 0 &&
3322 (nametag == NULL || errno != ENAMETOOLONG ||
3323 (renamename = newname, Urename(filename, renamename) < 0)))
3325 addr->basic_errno = errno;
3326 addr->message = string_sprintf("while renaming %s as %s",
3327 filename, renamename);
3331 /* Rename succeeded */
3335 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3337 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3339 } /* maildir or mailstore */
3340 } /* successful write + close */
3342 } /* write success */
3345 /* For a file, restore the last access time (atime), and set the modification
3346 time as required - changed if write succeeded, unchanged if not. */
3348 if (!isdirectory) utime(CS filename, ×);
3350 /* Notify comsat if configured to do so. It only makes sense if the configured
3351 file is the one that the comsat daemon knows about. */
3353 if (ob->notify_comsat && yield == OK && deliver_localpart != NULL)
3354 notify_comsat(deliver_localpart, saved_size);
3356 /* Pass back the final return code in the address structure */
3359 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3360 yield, addr->basic_errno, addr->more_errno);
3362 addr->transport_return = yield;
3364 /* Close the file, which will release the fcntl lock. For a directory write it
3365 is closed above, except in cases of error which goto RETURN, when we also need
3366 to remove the original file(s). For MBX locking, if all has gone well, before
3367 closing the file, see if we can get an exclusive lock on it, in which case we
3368 can unlink the /tmp lock file before closing it. This is always a non-blocking
3369 lock; there's no need to wait if we can't get it. If everything has gone right
3370 but close fails, defer the message. Then unlink the lock file, if present. This
3371 point in the code is jumped to from a number of places when errors are
3372 detected, in order to get the file closed and the lock file tidied away. */
3377 if (mbx_lockfd >= 0)
3379 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3380 ob->use_flock, 0) >= 0)
3383 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3384 Uunlink(mbx_lockname);
3386 (void)close(mbx_lockfd);
3388 #endif /* SUPPORT_MBX */
3390 if (fd >= 0 && close(fd) < 0 && yield == OK)
3392 addr->basic_errno = errno;
3393 addr->message = string_sprintf("while closing %s", filename);
3394 addr->transport_return = DEFER;
3397 if (hd >= 0) Uunlink(lockname);
3399 /* We get here with isdirectory and filename set only in error situations. */
3401 if (isdirectory && filename != NULL)
3404 if (dataname != filename) Uunlink(dataname);
3407 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3408 file name relies on time + pid. We must not allow the process to finish until
3409 the clock has move on by at least one microsecond. Usually we expect this
3410 already to be the case, but machines keep getting faster... */
3412 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3414 /* A return of FALSE means that if there was an error, a common error was
3415 put in the first address of a batch. */
3420 #endif /*!MACRO_PREDEF*/
3421 /* End of transport/appendfile.c */