1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2009 */
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 /* Encodings for mailbox formats, and their names. MBX format is actually
18 supported only if SUPPORT_MBX is set. */
20 enum { mbf_unix, mbf_mbx, mbf_smail, mbf_maildir, mbf_mailstore };
22 static const char *mailbox_formats[] = {
23 "unix", "mbx", "smail", "maildir", "mailstore" };
26 /* Check warn threshold only if quota size set or not a percentage threshold
27 percentage check should only be done if quota > 0 */
29 #define THRESHOLD_CHECK (ob->quota_warn_threshold_value > 0 && \
30 (!ob->quota_warn_threshold_is_percent || ob->quota_value > 0))
33 /* Options specific to the appendfile transport. They must be in alphabetic
34 order (note that "_" comes before the lower case letters). Some of them are
35 stored in the publicly visible instance block - these are flagged with the
38 optionlist appendfile_transport_options[] = {
39 #ifdef SUPPORT_MAILDIR
40 { "*expand_maildir_use_size_file", opt_stringptr,
41 (void *)offsetof(appendfile_transport_options_block, expand_maildir_use_size_file) },
43 { "*set_use_fcntl_lock",opt_bool | opt_hidden,
44 (void *)offsetof(appendfile_transport_options_block, set_use_fcntl) },
45 { "*set_use_flock_lock",opt_bool | opt_hidden,
46 (void *)offsetof(appendfile_transport_options_block, set_use_flock) },
47 { "*set_use_lockfile", opt_bool | opt_hidden,
48 (void *)offsetof(appendfile_transport_options_block, set_use_lockfile) },
50 { "*set_use_mbx_lock", opt_bool | opt_hidden,
51 (void *)offsetof(appendfile_transport_options_block, set_use_mbx_lock) },
53 { "allow_fifo", opt_bool,
54 (void *)offsetof(appendfile_transport_options_block, allow_fifo) },
55 { "allow_symlink", opt_bool,
56 (void *)offsetof(appendfile_transport_options_block, allow_symlink) },
57 { "batch_id", opt_stringptr | opt_public,
58 (void *)offsetof(transport_instance, batch_id) },
59 { "batch_max", opt_int | opt_public,
60 (void *)offsetof(transport_instance, batch_max) },
61 { "check_group", opt_bool,
62 (void *)offsetof(appendfile_transport_options_block, check_group) },
63 { "check_owner", opt_bool,
64 (void *)offsetof(appendfile_transport_options_block, check_owner) },
65 { "check_string", opt_stringptr,
66 (void *)offsetof(appendfile_transport_options_block, check_string) },
67 { "create_directory", opt_bool,
68 (void *)offsetof(appendfile_transport_options_block, create_directory) },
69 { "create_file", opt_stringptr,
70 (void *)offsetof(appendfile_transport_options_block, create_file_string) },
71 { "directory", opt_stringptr,
72 (void *)offsetof(appendfile_transport_options_block, dirname) },
73 { "directory_file", opt_stringptr,
74 (void *)offsetof(appendfile_transport_options_block, dirfilename) },
75 { "directory_mode", opt_octint,
76 (void *)offsetof(appendfile_transport_options_block, dirmode) },
77 { "escape_string", opt_stringptr,
78 (void *)offsetof(appendfile_transport_options_block, escape_string) },
79 { "file", opt_stringptr,
80 (void *)offsetof(appendfile_transport_options_block, filename) },
81 { "file_format", opt_stringptr,
82 (void *)offsetof(appendfile_transport_options_block, file_format) },
83 { "file_must_exist", opt_bool,
84 (void *)offsetof(appendfile_transport_options_block, file_must_exist) },
85 { "lock_fcntl_timeout", opt_time,
86 (void *)offsetof(appendfile_transport_options_block, lock_fcntl_timeout) },
87 { "lock_flock_timeout", opt_time,
88 (void *)offsetof(appendfile_transport_options_block, lock_flock_timeout) },
89 { "lock_interval", opt_time,
90 (void *)offsetof(appendfile_transport_options_block, lock_interval) },
91 { "lock_retries", opt_int,
92 (void *)offsetof(appendfile_transport_options_block, lock_retries) },
93 { "lockfile_mode", opt_octint,
94 (void *)offsetof(appendfile_transport_options_block, lockfile_mode) },
95 { "lockfile_timeout", opt_time,
96 (void *)offsetof(appendfile_transport_options_block, lockfile_timeout) },
97 { "mailbox_filecount", opt_stringptr,
98 (void *)offsetof(appendfile_transport_options_block, mailbox_filecount_string) },
99 { "mailbox_size", opt_stringptr,
100 (void *)offsetof(appendfile_transport_options_block, mailbox_size_string) },
101 #ifdef SUPPORT_MAILDIR
102 { "maildir_format", opt_bool,
103 (void *)offsetof(appendfile_transport_options_block, maildir_format ) } ,
104 { "maildir_quota_directory_regex", opt_stringptr,
105 (void *)offsetof(appendfile_transport_options_block, maildir_dir_regex) },
106 { "maildir_retries", opt_int,
107 (void *)offsetof(appendfile_transport_options_block, maildir_retries) },
108 { "maildir_tag", opt_stringptr,
109 (void *)offsetof(appendfile_transport_options_block, maildir_tag) },
110 { "maildir_use_size_file", opt_expand_bool,
111 (void *)offsetof(appendfile_transport_options_block, maildir_use_size_file ) } ,
112 { "maildirfolder_create_regex", opt_stringptr,
113 (void *)offsetof(appendfile_transport_options_block, maildirfolder_create_regex ) },
114 #endif /* SUPPORT_MAILDIR */
115 #ifdef SUPPORT_MAILSTORE
116 { "mailstore_format", opt_bool,
117 (void *)offsetof(appendfile_transport_options_block, mailstore_format ) },
118 { "mailstore_prefix", opt_stringptr,
119 (void *)offsetof(appendfile_transport_options_block, mailstore_prefix ) },
120 { "mailstore_suffix", opt_stringptr,
121 (void *)offsetof(appendfile_transport_options_block, mailstore_suffix ) },
122 #endif /* SUPPORT_MAILSTORE */
124 { "mbx_format", opt_bool,
125 (void *)offsetof(appendfile_transport_options_block, mbx_format ) } ,
126 #endif /* SUPPORT_MBX */
127 { "message_prefix", opt_stringptr,
128 (void *)offsetof(appendfile_transport_options_block, message_prefix) },
129 { "message_suffix", opt_stringptr,
130 (void *)offsetof(appendfile_transport_options_block, message_suffix) },
131 { "mode", opt_octint,
132 (void *)offsetof(appendfile_transport_options_block, mode) },
133 { "mode_fail_narrower",opt_bool,
134 (void *)offsetof(appendfile_transport_options_block, mode_fail_narrower) },
135 { "notify_comsat", opt_bool,
136 (void *)offsetof(appendfile_transport_options_block, notify_comsat) },
137 { "quota", opt_stringptr,
138 (void *)offsetof(appendfile_transport_options_block, quota) },
139 { "quota_directory", opt_stringptr,
140 (void *)offsetof(appendfile_transport_options_block, quota_directory) },
141 { "quota_filecount", opt_stringptr,
142 (void *)offsetof(appendfile_transport_options_block, quota_filecount) },
143 { "quota_is_inclusive", opt_bool,
144 (void *)offsetof(appendfile_transport_options_block, quota_is_inclusive) },
145 { "quota_size_regex", opt_stringptr,
146 (void *)offsetof(appendfile_transport_options_block, quota_size_regex) },
147 { "quota_warn_message", opt_stringptr | opt_public,
148 (void *)offsetof(transport_instance, warn_message) },
149 { "quota_warn_threshold", opt_stringptr,
150 (void *)offsetof(appendfile_transport_options_block, quota_warn_threshold) },
151 { "use_bsmtp", opt_bool,
152 (void *)offsetof(appendfile_transport_options_block, use_bsmtp) },
153 { "use_crlf", opt_bool,
154 (void *)offsetof(appendfile_transport_options_block, use_crlf) },
155 { "use_fcntl_lock", opt_bool_set,
156 (void *)offsetof(appendfile_transport_options_block, use_fcntl) },
157 { "use_flock_lock", opt_bool_set,
158 (void *)offsetof(appendfile_transport_options_block, use_flock) },
159 { "use_lockfile", opt_bool_set,
160 (void *)offsetof(appendfile_transport_options_block, use_lockfile) },
162 { "use_mbx_lock", opt_bool_set,
163 (void *)offsetof(appendfile_transport_options_block, use_mbx_lock) },
164 #endif /* SUPPORT_MBX */
167 /* Size of the options list. An extern variable has to be used so that its
168 address can appear in the tables drtables.c. */
170 int appendfile_transport_options_count =
171 sizeof(appendfile_transport_options)/sizeof(optionlist);
173 /* Default private options block for the appendfile transport. */
175 appendfile_transport_options_block appendfile_transport_option_defaults = {
178 US"q${base62:$tod_epoch}-$inode", /* dirfilename */
179 NULL, /* message_prefix (default reset in init if not bsmtp) */
180 NULL, /* message_suffix (ditto) */
181 US"anywhere", /* create_file_string (string value for create_file) */
183 NULL, /* quota_directory */
184 NULL, /* quota_filecount */
185 NULL, /* quota_size_regex */
186 NULL, /* quota_warn_threshold */
187 NULL, /* mailbox_size_string */
188 NULL, /* mailbox_filecount_string */
189 NULL, /* expand_maildir_use_size_file */
190 US"^(?:cur|new|\\..*)$", /* maildir_dir_regex */
191 NULL, /* maildir_tag */
192 NULL, /* maildirfolder_create_regex */
193 NULL, /* mailstore_prefix */
194 NULL, /* mailstore_suffix */
195 NULL, /* check_string (default changed for non-bsmtp file)*/
196 NULL, /* escape_string (ditto) */
197 NULL, /* file_format */
199 0, /* quota_warn_threshold_value */
200 -1, /* mailbox_size_value */
201 -1, /* mailbox_filecount_value */
202 0, /* quota_filecount_value */
203 APPENDFILE_MODE, /* mode */
204 APPENDFILE_DIRECTORY_MODE, /* dirmode */
205 APPENDFILE_LOCKFILE_MODE, /* lockfile_mode */
206 30*60, /* lockfile_timeout */
207 0, /* lock_fcntl_timeout */
208 0, /* lock_flock_timeout */
209 10, /* lock_retries */
210 3, /* lock_interval */
211 10, /* maildir_retries */
212 create_anywhere,/* create_file */
214 FALSE, /* allow_fifo */
215 FALSE, /* allow_symlink */
216 FALSE, /* check_group */
217 TRUE, /* check_owner */
218 TRUE, /* create_directory */
219 FALSE, /* notify_comsat */
220 TRUE, /* use_lockfile */
221 FALSE, /* set_use_lockfile */
222 TRUE, /* use_fcntl */
223 FALSE, /* set_use_fcntl */
224 FALSE, /* use_flock */
225 FALSE, /* set_use_flock */
226 FALSE, /* use_mbx_lock */
227 FALSE, /* set_use_mbx_lock */
228 FALSE, /* use_bsmtp */
229 FALSE, /* use_crlf */
230 FALSE, /* file_must_exist */
231 TRUE, /* mode_fail_narrower */
232 FALSE, /* maildir_format */
233 FALSE, /* maildir_use_size_file */
234 FALSE, /* mailstore_format */
235 FALSE, /* mbx_format */
236 FALSE, /* quota_warn_threshold_is_percent */
237 TRUE /* quota_is_inclusive */
242 /*************************************************
243 * Setup entry point *
244 *************************************************/
246 /* Called for each delivery in the privileged state, just before the uid/gid
247 are changed and the main entry point is called. We use this function to
248 expand any quota settings, so that it can access files that may not be readable
249 by the user. It is also used to pick up external mailbox size information, if
253 tblock points to the transport instance
254 addrlist addresses about to be delivered (not used)
255 dummy not used (doesn't pass back data)
256 uid the uid that will be set (not used)
257 gid the gid that will be set (not used)
258 errmsg where to put an error message
260 Returns: OK, FAIL, or DEFER
264 appendfile_transport_setup(transport_instance *tblock, address_item *addrlist,
265 transport_feedback *dummy, uid_t uid, gid_t gid, uschar **errmsg)
267 appendfile_transport_options_block *ob =
268 (appendfile_transport_options_block *)(tblock->options_block);
269 uschar *q = ob->quota;
270 double default_value = 0.0;
273 addrlist = addrlist; /* Keep picky compilers happy */
278 if (ob->expand_maildir_use_size_file)
279 ob->maildir_use_size_file = expand_check_condition(ob->expand_maildir_use_size_file,
280 US"`maildir_use_size_file` in transport", tblock->name);
282 /* Loop for quota, quota_filecount, quota_warn_threshold, mailbox_size,
285 for (i = 0; i < 5; i++)
288 uschar *which = NULL;
290 if (q == NULL) d = default_value; else
293 uschar *s = expand_string(q);
297 *errmsg = string_sprintf("Expansion of \"%s\" in %s transport failed: "
298 "%s", q, tblock->name, expand_string_message);
299 return search_find_defer? DEFER : FAIL;
302 d = Ustrtod(s, &rest);
304 /* Handle following characters K, M, G, %, the latter being permitted
305 for quota_warn_threshold only. A threshold with no quota setting is
308 if (tolower(*rest) == 'k') { d *= 1024.0; rest++; }
309 else if (tolower(*rest) == 'm') { d *= 1024.0*1024.0; rest++; }
310 else if (tolower(*rest) == 'g') { d *= 1024.0*1024.0*1024.0; rest++; }
311 else if (*rest == '%' && i == 2)
313 if (ob->quota_value <= 0 && !ob->maildir_use_size_file) d = 0;
314 else if ((int)d < 0 || (int)d > 100)
316 *errmsg = string_sprintf("Invalid quota_warn_threshold percentage (%d)"
317 " for %s transport", (int)d, tblock->name);
320 ob->quota_warn_threshold_is_percent = TRUE;
324 while (isspace(*rest)) rest++;
328 *errmsg = string_sprintf("Malformed value \"%s\" (expansion of \"%s\") "
329 "in %s transport", s, q, tblock->name);
334 /* Set each value, checking for possible overflow. */
339 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4) which = US"quota";
340 ob->quota_value = (off_t)d;
341 q = ob->quota_filecount;
345 if (d >= 2.0*1024.0*1024.0*1024.0) which = US"quota_filecount";
346 ob->quota_filecount_value = (int)d;
347 q = ob->quota_warn_threshold;
351 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
352 which = US"quota_warn_threshold";
353 ob->quota_warn_threshold_value = (off_t)d;
354 q = ob->mailbox_size_string;
355 default_value = -1.0;
359 if (d >= 2.0*1024.0*1024.0*1024.0 && sizeof(off_t) <= 4)
360 which = US"mailbox_size";;
361 ob->mailbox_size_value = (off_t)d;
362 q = ob->mailbox_filecount_string;
366 if (d >= 2.0*1024.0*1024.0*1024.0) which = US"mailbox_filecount";
367 ob->mailbox_filecount_value = (int)d;
373 *errmsg = string_sprintf("%s value %.10g is too large (overflow) in "
374 "%s transport", which, d, tblock->name);
384 /*************************************************
385 * Initialization entry point *
386 *************************************************/
388 /* Called for each instance, after its options have been read, to
389 enable consistency checks to be done, or anything else that needs
393 appendfile_transport_init(transport_instance *tblock)
395 appendfile_transport_options_block *ob =
396 (appendfile_transport_options_block *)(tblock->options_block);
398 /* Set up the setup entry point, to be called in the privileged state */
400 tblock->setup = appendfile_transport_setup;
402 /* Lock_retries must be greater than zero */
404 if (ob->lock_retries == 0) ob->lock_retries = 1;
406 /* Only one of a file name or directory name must be given. */
408 if (ob->filename != NULL && ob->dirname != NULL)
409 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
410 "only one of \"file\" or \"directory\" can be specified", tblock->name);
412 /* If a file name was specified, neither quota_filecount nor quota_directory
415 if (ob->filename != NULL)
417 if (ob->quota_filecount != NULL)
418 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
419 "quota_filecount must not be set without \"directory\"", tblock->name);
420 if (ob->quota_directory != NULL)
421 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
422 "quota_directory must not be set without \"directory\"", tblock->name);
425 /* The default locking depends on whether MBX is set or not. Change the
426 built-in default if none of the lock options has been explicitly set. At least
427 one form of locking is required in all cases, but mbx locking changes the
428 meaning of fcntl and flock locking. */
430 /* Not all operating systems provide flock(). For those that do, if flock is
431 requested, the default for fcntl is FALSE. */
436 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
437 "flock() support was not available in the operating system when this "
438 "binary was built", tblock->name);
439 #endif /* NO_FLOCK */
440 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
446 if (!ob->set_use_lockfile && !ob->set_use_fcntl && !ob->set_use_flock &&
447 !ob->set_use_mbx_lock)
449 ob->use_lockfile = ob->use_flock = FALSE;
450 ob->use_mbx_lock = ob->use_fcntl = TRUE;
452 else if (ob->use_mbx_lock)
454 if (!ob->set_use_lockfile) ob->use_lockfile = FALSE;
455 if (!ob->set_use_fcntl) ob->use_fcntl = FALSE;
456 if (!ob->set_use_flock) ob->use_flock = FALSE;
457 if (!ob->use_fcntl && !ob->use_flock) ob->use_fcntl = TRUE;
460 #endif /* SUPPORT_MBX */
462 if (!ob->use_fcntl && !ob->use_flock && !ob->use_lockfile && !ob->use_mbx_lock)
463 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
464 "no locking configured", tblock->name);
466 /* Unset timeouts for non-used locking types */
468 if (!ob->use_fcntl) ob->lock_fcntl_timeout = 0;
469 if (!ob->use_flock) ob->lock_flock_timeout = 0;
471 /* If a directory name was specified, only one of maildir or mailstore may be
472 specified, and if quota_filecount or quota_directory is given, quota must
475 if (ob->dirname != NULL)
477 if (ob->maildir_format && ob->mailstore_format)
478 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
479 "only one of maildir and mailstore may be specified", tblock->name);
480 if (ob->quota_filecount != NULL && ob->quota == NULL)
481 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
482 "quota must be set if quota_filecount is set", tblock->name);
483 if (ob->quota_directory != NULL && ob->quota == NULL)
484 log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s transport:\n "
485 "quota must be set if quota_directory is set", tblock->name);
488 /* If a fixed uid field is set, then a gid field must also be set. */
490 if (tblock->uid_set && !tblock->gid_set && tblock->expand_gid == NULL)
491 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
492 "user set without group for the %s transport", tblock->name);
494 /* If "create_file" is set, check that a valid option is given, and set the
497 if (ob->create_file_string != NULL)
500 if (Ustrcmp(ob->create_file_string, "anywhere") == 0) value = create_anywhere;
501 else if (Ustrcmp(ob->create_file_string, "belowhome") == 0) value =
503 else if (Ustrcmp(ob->create_file_string, "inhome") == 0)
504 value = create_inhome;
506 log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
507 "invalid value given for \"file_create\" for the %s transport: %s",
508 tblock->name, ob->create_file_string);
509 ob->create_file = value;
512 /* If quota_warn_threshold is set, set up default for warn_message. It may
513 not be used if the actual threshold for a given delivery ends up as zero,
514 of if it's given as a percentage and there's no quota setting. */
516 if (ob->quota_warn_threshold != NULL)
518 if (tblock->warn_message == NULL) tblock->warn_message = US
519 "To: $local_part@$domain\n"
520 "Subject: Your mailbox\n\n"
521 "This message is automatically created by mail delivery software (Exim).\n\n"
522 "The size of your mailbox has exceeded a warning threshold that is\n"
523 "set by the system administrator.\n";
526 /* If batch SMTP is set, force the check and escape strings, and arrange that
527 headers are also escaped. */
531 ob->check_string = US".";
532 ob->escape_string = US"..";
533 ob->options |= topt_escape_headers;
536 /* If not batch SMTP, not maildir, not mailstore, and directory is not set,
537 insert default values for for the affixes and the check/escape strings. */
539 else if (ob->dirname == NULL && !ob->maildir_format && !ob->mailstore_format)
541 if (ob->message_prefix == NULL) ob->message_prefix =
542 US"From ${if def:return_path{$return_path}{MAILER-DAEMON}} ${tod_bsdinbox}\n";
543 if (ob->message_suffix == NULL) ob->message_suffix = US"\n";
544 if (ob->check_string == NULL) ob->check_string = US"From ";
545 if (ob->escape_string == NULL) ob->escape_string = US">From ";
549 /* Set up the bitwise options for transport_write_message from the various
550 driver options. Only one of body_only and headers_only can be set. */
553 (tblock->body_only? topt_no_headers : 0) |
554 (tblock->headers_only? topt_no_body : 0) |
555 (tblock->return_path_add? topt_add_return_path : 0) |
556 (tblock->delivery_date_add? topt_add_delivery_date : 0) |
557 (tblock->envelope_to_add? topt_add_envelope_to : 0) |
558 ((ob->use_crlf || ob->mbx_format)? topt_use_crlf : 0);
563 /*************************************************
565 *************************************************/
567 /* The comsat daemon is the thing that provides asynchronous notification of
568 the arrival of local messages, if requested by the user by "biff y". It is a
569 BSD thing that uses a TCP/IP protocol for communication. A message consisting
570 of the text "user@offset" must be sent, where offset is the place in the
571 mailbox where new mail starts. There is no scope for telling it which file to
572 look at, which makes it a less than useful if mail is being delivered into a
573 non-standard place such as the user's home directory. In fact, it doesn't seem
574 to pay much attention to the offset.
578 offset offset in mailbox
584 notify_comsat(uschar *user, off_t offset)
591 DEBUG(D_transport) debug_printf("notify_comsat called\n");
593 sprintf(CS buffer, "%.200s@" OFF_T_FMT "\n", user, offset);
595 if ((sp = getservbyname("biff", "udp")) == NULL)
597 DEBUG(D_transport) debug_printf("biff/udp is an unknown service");
601 host.name = US"localhost";
605 /* This code is all set up to look up "localhost" and use all its addresses
606 until one succeeds. However, it appears that at least on some systems, comsat
607 doesn't listen on the ::1 address. So for the moment, just force the address to
608 be 127.0.0.1. At some future stage, when IPv6 really is superseding IPv4, this
609 can be changed. (But actually, comsat is probably dying out anyway.) */
612 if (host_find_byname(&host, NULL, 0, NULL, FALSE) == HOST_FIND_FAILED)
614 DEBUG(D_transport) debug_printf("\"localhost\" unknown\n");
619 host.address = US"127.0.0.1";
622 for (h = &host; h != NULL; h = h->next)
625 int host_af = (Ustrchr(h->address, ':') != NULL)? AF_INET6 : AF_INET;
627 DEBUG(D_transport) debug_printf("calling comsat on %s\n", h->address);
629 sock = ip_socket(SOCK_DGRAM, host_af);
630 if (sock < 0) continue;
632 /* Connect never fails for a UDP socket, so don't set a timeout. */
634 (void)ip_connect(sock, host_af, h->address, ntohs(sp->s_port), 0);
635 rc = send(sock, buffer, Ustrlen(buffer) + 1, 0);
640 debug_printf("send to comsat failed for %s: %s\n", strerror(errno),
647 /*************************************************
648 * Check the format of a file *
649 *************************************************/
651 /* This function is called when file_format is set, to check that an existing
652 file has the right format. The format string contains text/transport pairs. The
653 string matching is literal. we just read big_buffer_size bytes, because this is
654 all about the first few bytes of a file.
658 tblock the transport block
659 addr the address block - for inserting error data
661 Returns: pointer to the required transport, or NULL
665 check_file_format(int cfd, transport_instance *tblock, address_item *addr)
668 ((appendfile_transport_options_block *)(tblock->options_block))->file_format;
670 int len = read(cfd, data, sizeof(data));
674 DEBUG(D_transport) debug_printf("checking file format\n");
676 /* An empty file matches the current transport */
678 if (len == 0) return tblock;
680 /* Search the formats for a match */
682 while ((s = string_nextinlist(&format,&sep,big_buffer,big_buffer_size))!= NULL)
684 int slen = Ustrlen(s);
685 BOOL match = len >= slen && Ustrncmp(data, s, slen) == 0;
686 uschar *tp = string_nextinlist(&format, &sep, big_buffer, big_buffer_size);
689 transport_instance *tt;
690 for (tt = transports; tt != NULL; tt = tt->next)
691 if (Ustrcmp(tp, tt->name) == 0)
694 debug_printf("file format -> %s transport\n", tt->name);
697 addr->basic_errno = ERRNO_BADTRANSPORT;
698 addr->message = string_sprintf("%s transport (for %.*s format) not found",
704 /* Failed to find a match */
706 addr->basic_errno = ERRNO_FORMATUNKNOWN;
707 addr->message = US"mailbox file format unrecognized";
714 /*************************************************
715 * Check directory's files for quota *
716 *************************************************/
718 /* This function is called if quota is set for one of the delivery modes that
719 delivers into a specific directory. It scans the directory and stats all the
720 files in order to get a total size and count. This is an expensive thing to do,
721 but some people are prepared to bear the cost. Alternatively, if size_regex is
722 set, it is used as a regex to try to extract the size from the file name, a
723 strategy that some people use on maildir files on systems where the users have
726 The function is global, because it is also called from tf_maildir.c for maildir
727 folders (which should contain only regular files).
729 Note: Any problems can be written to debugging output, but cannot be written to
730 the log, because we are running as an unprivileged user here.
733 dirname the name of the directory
734 countptr where to add the file count (because this function recurses)
735 regex a compiled regex to get the size from a name
737 Returns: the sum of the sizes of the stattable files
738 zero if the directory cannot be opened
742 check_dir_size(uschar *dirname, int *countptr, const pcre *regex)
746 int count = *countptr;
750 dir = opendir(CS dirname);
751 if (dir == NULL) return 0;
753 while ((ent = readdir(dir)) != NULL)
755 uschar *name = US ent->d_name;
758 if (Ustrcmp(name, ".") == 0 || Ustrcmp(name, "..") == 0) continue;
762 /* If there's a regex, try to find the size using it */
767 if (pcre_exec(regex, NULL, CS name, Ustrlen(name), 0, 0, ovector,6) >= 2)
770 off_t size = (off_t)Ustrtod(name + ovector[2], &endptr);
771 if (endptr == name + ovector[3])
775 debug_printf("check_dir_size: size from %s is " OFF_T_FMT "\n", name,
781 debug_printf("check_dir_size: regex did not match %s\n", name);
784 /* No regex or no match for the regex, or captured non-digits */
786 if (!string_format(buffer, sizeof(buffer), "%s/%s", dirname, name))
789 debug_printf("check_dir_size: name too long: dir=%s name=%s\n", dirname,
794 if (Ustat(buffer, &statbuf) < 0)
797 debug_printf("check_dir_size: stat error %d for %s: %s\n", errno, buffer,
802 if ((statbuf.st_mode & S_IFMT) == S_IFREG)
803 sum += statbuf.st_size;
804 else if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
805 sum += check_dir_size(buffer, &count, regex);
810 debug_printf("check_dir_size: dir=%s sum=" OFF_T_FMT " count=%d\n", dirname,
820 /*************************************************
821 * Apply a lock to a file descriptor *
822 *************************************************/
824 /* This function applies a lock to a file descriptor, using a blocking or
825 non-blocking lock, depending on the timeout value. It can apply either or
826 both of a fcntl() and a flock() lock. However, not all OS support flock();
827 for those that don't, the use_flock option cannot be set.
830 fd the file descriptor
831 fcntltype type of lock, specified as F_WRLCK or F_RDLCK (that is, in
832 fcntl() format); the flock() type is deduced if needed
833 dofcntl do fcntl() locking
834 fcntltime non-zero to use blocking fcntl()
835 doflock do flock() locking
836 flocktime non-zero to use blocking flock()
838 Returns: yield of the fcntl() or flock() call, with errno preserved;
839 sigalrm_seen set if there has been a timeout
843 apply_lock(int fd, int fcntltype, BOOL dofcntl, int fcntltime, BOOL doflock,
848 struct flock lock_data;
849 lock_data.l_type = fcntltype;
850 lock_data.l_whence = lock_data.l_start = lock_data.l_len = 0;
852 sigalrm_seen = FALSE;
859 yield = fcntl(fd, F_SETLKW, &lock_data);
864 else yield = fcntl(fd, F_SETLK, &lock_data);
868 if (doflock && (yield >= 0))
870 int flocktype = (fcntltype == F_WRLCK)? LOCK_EX : LOCK_SH;
874 yield = flock(fd, flocktype);
879 else yield = flock(fd, flocktype | LOCK_NB);
881 #endif /* NO_FLOCK */
890 /*************************************************
891 * Copy message into MBX mailbox *
892 *************************************************/
894 /* This function is called when a message intended for a MBX mailbox has been
895 written to a temporary file. We can now get the size of the message and then
896 copy it in MBX format to the mailbox.
899 to_fd fd to write to (the real mailbox)
900 from_fd fd to read from (the temporary file)
901 saved_size current size of mailbox
903 Returns: OK if all went well, DEFER otherwise, with errno preserved
904 the number of bytes written are added to transport_count
905 by virtue of calling transport_write_block()
908 /* Values taken from c-client */
910 #define MBX_HDRSIZE 2048
911 #define MBX_NUSERFLAGS 30
914 copy_mbx_message(int to_fd, int from_fd, off_t saved_size)
920 /* If the current mailbox size is zero, write a header block */
926 memset (deliver_out_buffer, '\0', MBX_HDRSIZE);
927 sprintf(CS(s = deliver_out_buffer), "*mbx*\015\012%08lx00000000\015\012",
928 (long int)time(NULL));
929 for (i = 0; i < MBX_NUSERFLAGS; i++)
930 sprintf (CS(s += Ustrlen(s)), "\015\012");
931 if (!transport_write_block (to_fd, deliver_out_buffer, MBX_HDRSIZE))
935 DEBUG(D_transport) debug_printf("copying MBX message from temporary file\n");
937 /* Now construct the message's header from the time and the RFC822 file
938 size, including CRLFs, which is the size of the input (temporary) file. */
940 if (fstat(from_fd, &statbuf) < 0) return DEFER;
941 size = statbuf.st_size;
943 sprintf (CS deliver_out_buffer, "%s," OFF_T_FMT ";%08lx%04x-%08x\015\012",
944 tod_stamp(tod_mbx), size, 0L, 0, 0);
945 used = Ustrlen(deliver_out_buffer);
947 /* Rewind the temporary file, and copy it over in chunks. */
949 lseek(from_fd, 0 , SEEK_SET);
953 int len = read(from_fd, deliver_out_buffer + used,
954 DELIVER_OUT_BUFFER_SIZE - used);
957 if (len == 0) errno = ERRNO_MBXLENGTH;
960 if (!transport_write_block(to_fd, deliver_out_buffer, used + len))
968 #endif /* SUPPORT_MBX */
972 /*************************************************
973 * Check creation is permitted *
974 *************************************************/
976 /* This function checks whether a given file name is permitted to be created,
977 as controlled by the create_file option. If no home directory is set, however,
978 we can't do any tests.
981 filename the file name
982 create_file the ob->create_file option
984 Returns: TRUE if creation is permitted
988 check_creation(uschar *filename, int create_file)
992 if (deliver_home != NULL && create_file != create_anywhere)
994 int len = Ustrlen(deliver_home);
995 uschar *file = filename;
997 while (file[0] == '/' && file[1] == '/') file++;
998 if (Ustrncmp(file, deliver_home, len) != 0 || file[len] != '/' ||
999 ( Ustrchr(file+len+2, '/') != NULL &&
1001 create_file != create_belowhome ||
1002 Ustrstr(file+len, "/../") != NULL
1007 /* If yield is TRUE, the file name starts with the home directory, and does
1008 not contain any instances of "/../" in the "belowhome" case. However, it may
1009 still contain symbolic links. We can check for this by making use of
1010 realpath(), which most Unixes seem to have (but make it possible to cut this
1011 out). We can't just use realpath() on the whole file name, because we know
1012 the file itself doesn't exist, and intermediate directories may also not
1013 exist. What we want to know is the real path of the longest existing part of
1014 the path. That must match the home directory's beginning, whichever is the
1018 if (yield && create_file == create_belowhome)
1020 uschar *slash, *next;
1022 for (slash = Ustrrchr(file, '/'); /* There is known to be one */
1023 rp == NULL && slash > file; /* Stop if reached beginning */
1027 rp = US realpath(CS file, CS big_buffer);
1028 next = Ustrrchr(file, '/');
1032 /* If rp == NULL it means that none of the relevant directories exist.
1033 This is not a problem here - it means that no symbolic links can exist,
1034 which is all we are worried about. Otherwise, we must compare it
1035 against the start of the home directory. However, that may itself
1036 contain symbolic links, so we have to "realpath" it as well, if
1041 uschar hdbuffer[PATH_MAX+1];
1042 uschar *rph = deliver_home;
1043 int rlen = Ustrlen(big_buffer);
1045 rp = US realpath(CS deliver_home, CS hdbuffer);
1052 if (rlen > len) rlen = len;
1053 if (Ustrncmp(rph, big_buffer, rlen) != 0)
1056 DEBUG(D_transport) debug_printf("Real path \"%s\" does not match \"%s\"\n",
1057 big_buffer, deliver_home);
1061 #endif /* NO_REALPATH */
1069 /*************************************************
1070 * Main entry point *
1071 *************************************************/
1073 /* See local README for general interface details. This transport always
1074 returns FALSE, indicating that the status which has been placed in the first
1075 address should be copied to any other addresses in a batch.
1077 Appendfile delivery is tricky and has led to various security problems in other
1078 mailers. The logic used here is therefore laid out in some detail. When this
1079 function is called, we are running in a subprocess which has had its gid and
1080 uid set to the appropriate values. Therefore, we cannot write directly to the
1081 exim logs. Any errors must be handled by setting appropriate return codes.
1082 Note that the default setting for addr->transport_return is DEFER, so it need
1083 not be set unless some other value is required.
1085 The code below calls geteuid() rather than getuid() to get the current uid
1086 because in weird configurations not running setuid root there may be a
1087 difference. In the standard configuration, where setuid() has been used in the
1088 delivery process, there will be no difference between the uid and the euid.
1090 (1) If the af_file flag is set, this is a delivery to a file after .forward or
1091 alias expansion. Otherwise, there must be a configured file name or
1094 The following items apply in the case when a file name (as opposed to a
1095 directory name) is given, that is, when appending to a single file:
1097 (2f) Expand the file name.
1099 (3f) If the file name is /dev/null, return success (optimization).
1101 (4f) If the file_format options is set, open the file for reading, and check
1102 that the bytes at the start of the file match one of the given strings.
1103 If the check indicates a transport other than the current one should be
1104 used, pass control to that other transport. Otherwise continue. An empty
1105 or non-existent file matches the current transport. The file is closed
1108 (5f) If a lock file is required, create it (see extensive separate comments
1109 below about the algorithm for doing this). It is important to do this
1110 before opening the mailbox if NFS is in use.
1112 (6f) Stat the file, using lstat() rather than stat(), in order to pick up
1113 details of any symbolic link.
1115 (7f) If the file already exists:
1117 Check the owner and group if necessary, and defer if they are wrong.
1119 If it is a symbolic link AND the allow_symlink option is set (NOT the
1120 default), go back to (6f) but this time use stat() instead of lstat().
1122 If it's not a regular file (or FIFO when permitted), defer delivery.
1124 Check permissions. If the required permissions are *less* than the
1125 existing ones, or supplied by the address (often by the user via filter),
1126 chmod() the file. Otherwise, defer.
1128 Save the inode number.
1130 Open with O_RDRW + O_APPEND, thus failing if the file has vanished.
1132 If open fails because the file does not exist, go to (6f); on any other
1135 Check the inode number hasn't changed - I realize this isn't perfect (an
1136 inode can be reused) but it's cheap and will catch some of the races.
1138 Check it's still a regular file (or FIFO if permitted).
1140 Check that the owner and permissions haven't changed.
1142 If file_format is set, check that the file still matches the format for
1143 the current transport. If not, defer delivery.
1145 (8f) If file does not exist initially:
1147 Open with O_WRONLY + O_EXCL + O_CREAT with configured mode, unless we know
1148 this is via a symbolic link (only possible if allow_symlinks is set), in
1149 which case don't use O_EXCL, as it dosn't work.
1151 If open fails because the file already exists, go to (6f). To avoid
1152 looping for ever in a situation where the file is continuously being
1153 created and deleted, all of this happens inside a loop that operates
1154 lock_retries times and includes the fcntl and flock locking. If the
1155 loop completes without the file getting opened, defer and request
1156 freezing, because something really weird is happening.
1158 If open fails for any other reason, defer for subsequent delivery except
1159 when this is a file delivery resulting from an alias or forward expansion
1160 and the error is EPERM or ENOENT or EACCES, in which case FAIL as this is
1161 most likely a user rather than a configuration error.
1163 (9f) We now have the file checked and open for writing. If so configured, lock
1164 it using fcntl, flock, or MBX locking rules. If this fails, close the file
1165 and goto (6f), up to lock_retries times, after sleeping for a while. If it
1166 still fails, give up and defer delivery.
1168 (10f)Save the access time (for subsequent restoration) and the size of the
1169 file, for comsat and for re-setting if delivery fails in the middle -
1170 e.g. for quota exceeded.
1172 The following items apply in the case when a directory name is given:
1174 (2d) Create a new file in the directory using a temporary name, by opening for
1175 writing and with O_CREAT. If maildir format is being used, the file
1176 is created in a temporary subdirectory with a prescribed name. If
1177 mailstore format is being used, the envelope file is first created with a
1178 temporary name, then the data file.
1180 The following items apply in all cases:
1182 (11) We now have the file open for writing, and locked if it was given as a
1183 file name. Write the message and flush the file, unless there is a setting
1184 of the local quota option, in which case we can check for its excession
1185 without doing any writing.
1187 In the case of MBX format mailboxes, the message is first written to a
1188 temporary file, in order to get its correct length. This is then copied to
1189 the real file, preceded by an MBX header.
1191 If there is a quota error on writing, defer the address. Timeout logic
1192 will determine for how long retries are attempted. We restore the mailbox
1193 to its original length if it's a single file. There doesn't seem to be a
1194 uniform error code for quota excession (it even differs between SunOS4
1195 and some versions of SunOS5) so a system-dependent macro called
1196 ERRNO_QUOTA is used for it, and the value gets put into errno_quota at
1199 For any other error (most commonly disk full), do the same.
1201 The following applies after appending to a file:
1203 (12f)Restore the atime; notify_comsat if required; close the file (which
1204 unlocks it if it was locked). Delete the lock file if it exists.
1206 The following applies after writing a unique file in a directory:
1208 (12d)For maildir format, rename the file into the new directory. For mailstore
1209 format, rename the envelope file to its correct name. Otherwise, generate
1210 a unique name from the directory_file option, and rename to that, possibly
1211 trying a few times if the file exists and re-expanding the name gives a
1214 This transport yields FAIL only when a file name is generated by an alias or
1215 forwarding operation and attempting to open it gives EPERM, ENOENT, or EACCES.
1216 All other failures return DEFER (in addr->transport_return). */
1220 appendfile_transport_entry(
1221 transport_instance *tblock, /* data for this instantiation */
1222 address_item *addr) /* address we are working on */
1224 appendfile_transport_options_block *ob =
1225 (appendfile_transport_options_block *)(tblock->options_block);
1226 struct stat statbuf;
1227 uschar *fdname = NULL;
1228 uschar *filename = NULL;
1229 uschar *hitchname = NULL;
1230 uschar *dataname = NULL;
1231 uschar *lockname = NULL;
1232 uschar *newname = NULL;
1233 uschar *nametag = NULL;
1235 uschar *filecount_msg = US"";
1237 struct utimbuf times;
1238 struct timeval msg_tv;
1239 BOOL disable_quota = FALSE;
1240 BOOL isdirectory = FALSE;
1241 BOOL isfifo = FALSE;
1242 BOOL wait_for_tick = FALSE;
1243 uid_t uid = geteuid(); /* See note above */
1244 gid_t gid = getegid();
1246 int mode = (addr->mode > 0)? addr->mode : ob->mode;
1247 off_t saved_size = -1;
1248 off_t mailbox_size = ob->mailbox_size_value;
1249 int mailbox_filecount = ob->mailbox_filecount_value;
1257 int mbx_lockfd = -1;
1258 uschar mbx_lockname[40];
1259 FILE *temp_file = NULL;
1260 #endif /* SUPPORT_MBX */
1262 #ifdef SUPPORT_MAILDIR
1263 int maildirsize_fd = -1; /* fd for maildirsize file */
1264 int maildir_save_errno;
1268 DEBUG(D_transport) debug_printf("appendfile transport entered\n");
1270 /* An "address_file" or "address_directory" transport is used to deliver to
1271 files specified via .forward or an alias file. Prior to release 4.20, the
1272 "file" and "directory" options were ignored in this case. This has been changed
1273 to allow the redirection data to specify what is in effect a folder, whose
1274 location is determined by the options on the transport.
1276 Compatibility with the case when neither option is set is retained by forcing a
1277 value for the file or directory name. A directory delivery is assumed if the
1278 last character of the path from the router is '/'.
1280 The file path is in the local part of the address, but not in the $local_part
1281 variable (that holds the parent local part). It is, however, in the
1282 $address_file variable. Below, we update the local part in the address if it
1283 changes by expansion, so that the final path ends up in the log. */
1285 if (testflag(addr, af_file) &&
1286 ob->filename == NULL &&
1287 ob->dirname == NULL)
1289 fdname = US"$address_file";
1290 if (address_file[Ustrlen(address_file)-1] == '/' ||
1291 ob->maildir_format ||
1292 ob->mailstore_format)
1296 /* Handle (a) an "address file" delivery where "file" or "directory" is
1297 explicitly set and (b) a non-address_file delivery, where one of "file" or
1298 "directory" must be set; initialization ensures that they are not both set. */
1302 fdname = ob->filename;
1305 fdname = ob->dirname;
1310 addr->transport_return = PANIC;
1311 addr->message = string_sprintf("Mandatory file or directory option "
1312 "missing from %s transport", tblock->name);
1317 /* Maildir and mailstore require a directory */
1319 if ((ob->maildir_format || ob->mailstore_format) && !isdirectory)
1321 addr->transport_return = PANIC;
1322 addr->message = string_sprintf("mail%s_format requires \"directory\" "
1323 "to be specified for the %s transport",
1324 ob->maildir_format? "dir" : "store", tblock->name);
1328 path = expand_string(fdname);
1332 addr->transport_return = PANIC;
1333 addr->message = string_sprintf("Expansion of \"%s\" (file or directory "
1334 "name for %s transport) failed: %s", fdname, tblock->name,
1335 expand_string_message);
1341 addr->message = string_sprintf("appendfile: file or directory name "
1342 "\"%s\" is not absolute", path);
1343 addr->basic_errno = ERRNO_NOTABSOLUTE;
1347 /* For a file delivery, make sure the local part in the address(es) is updated
1348 to the true local part. */
1350 if (testflag(addr, af_file))
1352 address_item *addr2;
1353 for (addr2 = addr; addr2 != NULL; addr2 = addr2->next)
1354 addr2->local_part = string_copy(path);
1357 /* The available mailbox formats depend on whether it is a directory or a file
1363 #ifdef SUPPORT_MAILDIR
1364 (ob->maildir_format)? mbf_maildir :
1366 #ifdef SUPPORT_MAILSTORE
1367 (ob->mailstore_format)? mbf_mailstore :
1375 (ob->mbx_format)? mbf_mbx :
1382 debug_printf("appendfile: mode=%o notify_comsat=%d quota=" OFF_T_FMT
1383 " warning=" OFF_T_FMT "%s\n"
1384 " %s=%s format=%s\n message_prefix=%s\n message_suffix=%s\n "
1385 "maildir_use_size_file=%s\n",
1386 mode, ob->notify_comsat, ob->quota_value,
1387 ob->quota_warn_threshold_value,
1388 ob->quota_warn_threshold_is_percent? "%" : "",
1389 isdirectory? "directory" : "file",
1390 path, mailbox_formats[mbformat],
1391 (ob->message_prefix == NULL)? US"null" : string_printing(ob->message_prefix),
1392 (ob->message_suffix == NULL)? US"null" : string_printing(ob->message_suffix),
1393 (ob->maildir_use_size_file)? "yes" : "no");
1395 if (!isdirectory) debug_printf(" locking by %s%s%s%s%s\n",
1396 ob->use_lockfile? "lockfile " : "",
1397 ob->use_mbx_lock? "mbx locking (" : "",
1398 ob->use_fcntl? "fcntl " : "",
1399 ob->use_flock? "flock" : "",
1400 ob->use_mbx_lock? ")" : "");
1403 /* If the -N option is set, can't do any more. */
1408 debug_printf("*** delivery by %s transport bypassed by -N option\n",
1410 addr->transport_return = OK;
1414 /* Handle the case of a file name. If the file name is /dev/null, we can save
1415 ourselves some effort and just give a success return right away. */
1419 BOOL use_lstat = TRUE;
1420 BOOL file_opened = FALSE;
1421 BOOL allow_creation_here = TRUE;
1423 if (Ustrcmp(path, "/dev/null") == 0)
1425 addr->transport_return = OK;
1429 /* Set the name of the file to be opened, and the file to which the data
1430 is written, and find out if we are permitted to create a non-existent file. */
1432 dataname = filename = path;
1433 allow_creation_here = check_creation(filename, ob->create_file);
1435 /* If ob->create_directory is set, attempt to create the directories in
1436 which this mailbox lives, but only if we are permitted to create the file
1437 itself. We know we are dealing with an absolute path, because this was
1440 if (ob->create_directory && allow_creation_here)
1442 uschar *p = Ustrrchr(path, '/');
1444 if (!directory_make(NULL, path, ob->dirmode, FALSE))
1446 addr->basic_errno = errno;
1448 string_sprintf("failed to create directories for %s: %s", path,
1450 DEBUG(D_transport) debug_printf("%s transport: %s\n", tblock->name, path);
1456 /* If file_format is set we must check that any existing file matches one of
1457 the configured formats by checking the bytes it starts with. A match then
1458 indicates a specific transport - if it is not this one, pass control to it.
1459 Otherwise carry on here. An empty or non-existent file matches the current
1460 transport. We don't need to distinguish between non-existence and other open
1461 failures because if an existing file fails to open here, it will also fail
1462 again later when O_RDWR is used. */
1464 if (ob->file_format != NULL)
1466 int cfd = Uopen(path, O_RDONLY, 0);
1469 transport_instance *tt = check_file_format(cfd, tblock, addr);
1472 /* If another transport is indicated, call it and return; if no transport
1473 was found, just return - the error data will have been set up.*/
1479 set_process_info("delivering %s to %s using %s", message_id,
1480 addr->local_part, tt->name);
1481 debug_print_string(tt->debug_string);
1482 addr->transport = tt;
1483 (tt->info->code)(tt, addr);
1490 /* The locking of mailbox files is worse than the naming of cats, which is
1491 known to be "a difficult matter" (T.S. Eliot) and just as cats must have
1492 three different names, so several different styles of locking are used.
1494 Research in other programs that lock mailboxes shows that there is no
1495 universally standard method. Having mailboxes NFS-mounted on the system that
1496 is delivering mail is not the best thing, but people do run like this,
1497 and so the code must do its best to cope.
1499 Three different locking mechanisms are supported. The initialization function
1500 checks that at least one is configured.
1504 Unless no_use_lockfile is set, we attempt to build a lock file in a way that
1505 will work over NFS. Only after that is done do we actually open the mailbox
1506 and apply locks to it (if configured).
1508 Originally, Exim got the file opened before doing anything about locking.
1509 However, a very occasional problem was observed on Solaris 2 when delivering
1510 over NFS. It is seems that when a file is opened with O_APPEND, the file size
1511 gets remembered at open time. If another process on another host (that's
1512 important) has the file open and locked and writes to it and then releases
1513 the lock while the first process is waiting to get the lock, the first
1514 process may fail to write at the new end point of the file - despite the very
1515 definite statement about O_APPEND in the man page for write(). Experiments
1516 have reproduced this problem, but I do not know any way of forcing a host to
1517 update its attribute cache for an open NFS file. It would be nice if it did
1518 so when a lock was taken out, but this does not seem to happen. Anyway, to
1519 reduce the risk of this problem happening, we now create the lock file
1520 (if configured) *before* opening the mailbox. That will prevent two different
1521 Exims opening the file simultaneously. It may not prevent clashes with MUAs,
1522 however, but Pine at least seems to operate in the same way.
1524 Lockfiles should normally be used when NFS is involved, because of the above
1527 The logic for creating the lock file is:
1529 . The name of the lock file is <mailbox-name>.lock
1531 . First, create a "hitching post" name by adding the primary host name,
1532 current time and pid to the lock file name. This should be unique.
1534 . Create the hitching post file using WRONLY + CREAT + EXCL.
1536 . If that fails EACCES, we assume it means that the user is unable to create
1537 files in the mail spool directory. Some installations might operate in this
1538 manner, so there is a configuration option to allow this state not to be an
1539 error - we proceed to lock using fcntl only, after the file is open.
1541 . Otherwise, an error causes a deferment of the address.
1543 . Hard link the hitching post to the lock file name.
1545 . If the link succeeds, we have successfully created the lock file. Simply
1546 close and unlink the hitching post file.
1548 . If the link does not succeed, proceed as follows:
1550 o Fstat the hitching post file, and then close and unlink it.
1552 o Now examine the stat data. If the number of links to the file is exactly
1553 2, the linking succeeded but for some reason, e.g. an NFS server crash,
1554 the return never made it back, so the link() function gave a failure
1557 . This method allows for the lock file to be created by some other process
1558 right up to the moment of the attempt to hard link it, and is also robust
1559 against NFS server crash-reboots, which would probably result in timeouts
1560 in the middle of link().
1562 . System crashes may cause lock files to get left lying around, and some means
1563 of flushing them is required. The approach of writing a pid (used by smail
1564 and by elm) into the file isn't useful when NFS may be in use. Pine uses a
1565 timeout, which seems a better approach. Since any program that writes to a
1566 mailbox using a lock file should complete its task very quickly, Pine
1567 removes lock files that are older than 5 minutes. We allow the value to be
1568 configurable on the transport.
1572 If use_fcntl_lock is set, then Exim gets an exclusive fcntl() lock on the
1573 mailbox once it is open. This is done by default with a non-blocking lock.
1574 Failures to lock cause retries after a sleep, but only for a certain number
1575 of tries. A blocking lock is deliberately not used so that we don't hold the
1576 mailbox open. This minimizes the possibility of the NFS problem described
1577 under LOCK FILES above, if for some reason NFS deliveries are happening
1578 without lock files. However, the use of a non-blocking lock and sleep, though
1579 the safest approach, does not give the best performance on very busy systems.
1580 A blocking lock plus timeout does better. Therefore Exim has an option to
1581 allow it to work this way. If lock_fcntl_timeout is set greater than zero, it
1582 enables the use of blocking fcntl() calls.
1586 If use_flock_lock is set, then Exim gets an exclusive flock() lock in the
1587 same manner as for fcntl locking above. No-blocking/timeout is also set as
1588 above in lock_flock_timeout. Not all operating systems provide or support
1589 flock(). For those that don't (as determined by the definition of LOCK_SH in
1590 /usr/include/sys/file.h), use_flock_lock may not be set. For some OS, flock()
1591 is implemented (not precisely) on top of fcntl(), which means there's no
1592 point in actually using it.
1596 If use_mbx_lock is set (this is supported only if SUPPORT_MBX is defined)
1597 then the rules used for locking in c-client are used. Exim takes out a shared
1598 lock on the mailbox file, and an exclusive lock on the file whose name is
1599 /tmp/.<device-number>.<inode-number>. The shared lock on the mailbox stops
1600 any other MBX client from getting an exclusive lock on it and expunging it.
1601 It also stops any other MBX client from unlinking the /tmp lock when it has
1604 The exclusive lock on the /tmp file prevents any other MBX client from
1605 updating the mailbox in any way. When writing is finished, if an exclusive
1606 lock on the mailbox can be obtained, indicating there are no current sharers,
1607 the /tmp file is unlinked.
1609 MBX locking can use either fcntl() or flock() locking. If neither
1610 use_fcntl_lock or use_flock_lock is set, it defaults to using fcntl() only.
1611 The calls for getting these locks are by default non-blocking, as for non-mbx
1612 locking, but can be made blocking by setting lock_fcntl_timeout and/or
1613 lock_flock_timeout as appropriate. As MBX delivery doesn't work over NFS, it
1614 probably makes sense to set timeouts for any MBX deliveries. */
1617 /* Build a lock file if configured to do so - the existence of a lock
1618 file is subsequently checked by looking for a non-negative value of the
1619 file descriptor hd - even though the file is no longer open. */
1621 if (ob->use_lockfile)
1623 lockname = string_sprintf("%s.lock", filename);
1624 hitchname = string_sprintf( "%s.%s.%08x.%08x", lockname, primary_hostname,
1625 (unsigned int)(time(NULL)), (unsigned int)getpid());
1627 DEBUG(D_transport) debug_printf("lock name: %s\nhitch name: %s\n", lockname,
1630 /* Lock file creation retry loop */
1632 for (i = 0; i < ob->lock_retries; sleep(ob->lock_interval), i++)
1635 hd = Uopen(hitchname, O_WRONLY | O_CREAT | O_EXCL, ob->lockfile_mode);
1639 addr->basic_errno = errno;
1641 string_sprintf("creating lock file hitching post %s "
1642 "(euid=%ld egid=%ld)", hitchname, (long int)geteuid(),
1643 (long int)getegid());
1647 /* Attempt to hitch the hitching post to the lock file. If link()
1648 succeeds (the common case, we hope) all is well. Otherwise, fstat the
1649 file, and get rid of the hitching post. If the number of links was 2,
1650 the link was created, despite the failure of link(). If the hitch was
1651 not successful, try again, having unlinked the lock file if it is too
1654 There's a version of Linux (2.0.27) which doesn't update its local cache
1655 of the inode after link() by default - which many think is a bug - but
1656 if the link succeeds, this code will be OK. It just won't work in the
1657 case when link() fails after having actually created the link. The Linux
1658 NFS person is fixing this; a temporary patch is available if anyone is
1659 sufficiently worried. */
1661 if ((rc = Ulink(hitchname, lockname)) != 0) fstat(hd, &statbuf);
1664 if (rc != 0 && statbuf.st_nlink != 2)
1666 if (ob->lockfile_timeout > 0 && Ustat(lockname, &statbuf) == 0 &&
1667 time(NULL) - statbuf.st_ctime > ob->lockfile_timeout)
1669 DEBUG(D_transport) debug_printf("unlinking timed-out lock file\n");
1672 DEBUG(D_transport) debug_printf("link of hitching post failed - retrying\n");
1676 DEBUG(D_transport) debug_printf("lock file created\n");
1680 /* Check for too many tries at creating the lock file */
1682 if (i >= ob->lock_retries)
1684 addr->basic_errno = ERRNO_LOCKFAILED;
1685 addr->message = string_sprintf("failed to lock mailbox %s (lock file)",
1692 /* We now have to get the file open. First, stat() it and act on existence or
1693 non-existence. This is in a loop to handle the case of a file's being created
1694 or deleted as we watch, and also to handle retries when the locking fails.
1695 Rather than holding the file open while waiting for the fcntl() and/or
1696 flock() lock, we close and do the whole thing again. This should be safer,
1697 especially for NFS files, which might get altered from other hosts, making
1698 their cached sizes incorrect.
1700 With the default settings, no symlinks are permitted, but there is an option
1701 to permit symlinks for those sysadmins that know what they are doing.
1702 Shudder. However, insist that the initial symlink is owned by the right user.
1703 Thus lstat() is used initially; if a symlink is discovered, the loop is
1704 repeated such that stat() is used, to look at the end file. */
1706 for (i = 0; i < ob->lock_retries; i++)
1708 int sleep_before_retry = TRUE;
1709 file_opened = FALSE;
1711 if((use_lstat? Ulstat(filename, &statbuf) : Ustat(filename, &statbuf)) != 0)
1713 /* Let's hope that failure to stat (other than non-existence) is a
1716 if (errno != ENOENT)
1718 addr->basic_errno = errno;
1719 addr->message = string_sprintf("attempting to stat mailbox %s",
1724 /* File does not exist. If it is required to pre-exist this state is an
1727 if (ob->file_must_exist)
1729 addr->basic_errno = errno;
1730 addr->message = string_sprintf("mailbox %s does not exist, "
1731 "but file_must_exist is set", filename);
1735 /* If not permitted to create this file because it isn't in or below
1736 the home directory, generate an error. */
1738 if (!allow_creation_here)
1740 addr->basic_errno = ERRNO_BADCREATE;
1741 addr->message = string_sprintf("mailbox %s does not exist, "
1742 "but creation outside the home directory is not permitted",
1747 /* Attempt to create and open the file. If open fails because of
1748 pre-existence, go round the loop again. For any other error, defer the
1749 address, except for an alias or forward generated file name with EPERM,
1750 ENOENT, or EACCES, as those are most likely to be user errors rather
1751 than Exim config errors. When a symbolic link is permitted and points
1752 to a non-existent file, we get here with use_lstat = FALSE. In this case
1753 we mustn't use O_EXCL, since it doesn't work. The file is opened RDRW for
1754 consistency and because MBX locking requires it in order to be able to
1755 get a shared lock. */
1757 fd = Uopen(filename, O_RDWR | O_APPEND | O_CREAT |
1758 (use_lstat? O_EXCL : 0), mode);
1761 if (errno == EEXIST) continue;
1762 addr->basic_errno = errno;
1763 addr->message = string_sprintf("while creating mailbox %s",
1765 if (testflag(addr, af_file) &&
1766 (errno == EPERM || errno == ENOENT || errno == EACCES))
1767 addr->transport_return = FAIL;
1771 /* We have successfully created and opened the file. Ensure that the group
1772 and the mode are correct. */
1774 (void)Uchown(filename, uid, gid);
1775 (void)Uchmod(filename, mode);
1779 /* The file already exists. Test its type, ownership, and permissions, and
1780 save the inode for checking later. If symlinks are permitted (not the
1781 default or recommended state) it may be a symlink that already exists.
1782 Check its ownership and then look for the file at the end of the link(s).
1783 This at least prevents one user creating a symlink for another user in
1784 a sticky directory. */
1788 int oldmode = (int)statbuf.st_mode;
1789 ino_t inode = statbuf.st_ino;
1790 BOOL islink = (oldmode & S_IFMT) == S_IFLNK;
1792 isfifo = FALSE; /* In case things are changing */
1794 /* Check owner if required - the default. */
1796 if (ob->check_owner && statbuf.st_uid != uid)
1798 addr->basic_errno = ERRNO_BADUGID;
1799 addr->message = string_sprintf("mailbox %s%s has wrong uid "
1800 "(%ld != %ld)", filename,
1801 islink? " (symlink)" : "",
1802 (long int)(statbuf.st_uid), (long int)uid);
1806 /* Group is checked only if check_group is set. */
1808 if (ob->check_group && statbuf.st_gid != gid)
1810 addr->basic_errno = ERRNO_BADUGID;
1811 addr->message = string_sprintf("mailbox %s%s has wrong gid (%d != %d)",
1812 filename, islink? " (symlink)" : "", statbuf.st_gid, gid);
1816 /* Just in case this is a sticky-bit mail directory, we don't want
1817 users to be able to create hard links to other users' files. */
1819 if (statbuf.st_nlink != 1)
1821 addr->basic_errno = ERRNO_NOTREGULAR;
1822 addr->message = string_sprintf("mailbox %s%s has too many links (%d)",
1823 filename, islink? " (symlink)" : "", statbuf.st_nlink);
1828 /* If symlinks are permitted (not recommended), the lstat() above will
1829 have found the symlink. Its ownership has just been checked; go round
1830 the loop again, using stat() instead of lstat(). That will never yield a
1833 if (islink && ob->allow_symlink)
1836 i--; /* Don't count this time round */
1840 /* An actual file exists. Check that it is a regular file, or FIFO
1843 if (ob->allow_fifo && (oldmode & S_IFMT) == S_IFIFO) isfifo = TRUE;
1845 else if ((oldmode & S_IFMT) != S_IFREG)
1847 addr->basic_errno = ERRNO_NOTREGULAR;
1848 addr->message = string_sprintf("mailbox %s is not a regular file%s",
1849 filename, ob->allow_fifo? " or named pipe" : "");
1853 /* If the mode is not what it would be for a newly created file, change
1854 the permissions if the mode is supplied for the address. Otherwise,
1855 reduce but do not extend the permissions. If the newly created
1856 permissions are greater than the existing permissions, don't change
1857 things when the mode is not from the address. */
1859 if ((oldmode = (oldmode & 07777)) != mode)
1861 int diffs = oldmode ^ mode;
1862 if (addr->mode > 0 || (diffs & oldmode) == diffs)
1864 DEBUG(D_transport) debug_printf("chmod %o %s\n", mode, filename);
1865 if (Uchmod(filename, mode) < 0)
1867 addr->basic_errno = errno;
1868 addr->message = string_sprintf("attempting to chmod mailbox %s",
1875 /* Mode not from address, and newly-created permissions are greater
1876 than existing permissions. Default is to complain, but it can be
1877 configured to go ahead and try to deliver anyway if that's what
1878 the administration wants. */
1880 else if (ob->mode_fail_narrower)
1882 addr->basic_errno = ERRNO_BADMODE;
1883 addr->message = string_sprintf("mailbox %s has the wrong mode %o "
1884 "(%o expected)", filename, oldmode, mode);
1889 /* We are happy with the existing file. Open it, and then do further
1890 tests to ensure that it is the same file that we were just looking at.
1891 If the file does not now exist, restart this loop, going back to using
1892 lstat again. For an NFS error, just defer; other opening errors are
1893 more serious. The file is opened RDWR so that its format can be checked,
1894 and also MBX locking requires the use of a shared (read) lock. However,
1895 a FIFO is opened WRONLY + NDELAY so that it fails if there is no process
1896 reading the pipe. */
1898 fd = Uopen(filename, isfifo? (O_WRONLY|O_NDELAY) : (O_RDWR|O_APPEND),
1902 if (errno == ENOENT)
1907 addr->basic_errno = errno;
1910 addr->message = string_sprintf("while opening named pipe %s "
1911 "(could mean no process is reading it)", filename);
1913 else if (errno != EWOULDBLOCK)
1915 addr->message = string_sprintf("while opening mailbox %s", filename);
1920 /* This fstat really shouldn't fail, as we have an open file! There's a
1921 dilemma here. We use fstat in order to be sure we are peering at the file
1922 we have got open. However, that won't tell us if the file was reached
1923 via a symbolic link. We checked this above, but there is a race exposure
1924 if the link was created between the previous lstat and the open. However,
1925 it would have to be created with the same inode in order to pass the
1926 check below. If ob->allow_symlink is set, causing the use of stat rather
1927 than lstat above, symbolic links may be there anyway, and the checking is
1930 if (fstat(fd, &statbuf) < 0)
1932 addr->basic_errno = errno;
1933 addr->message = string_sprintf("attempting to stat open mailbox %s",
1938 /* Check the inode; this is isn't a perfect check, but gives some
1941 if (inode != statbuf.st_ino)
1943 addr->basic_errno = ERRNO_INODECHANGED;
1944 addr->message = string_sprintf("opened mailbox %s inode number changed "
1945 "from %d to %ld", filename, inode, statbuf.st_ino);
1946 addr->special_action = SPECIAL_FREEZE;
1950 /* Check it's still a regular file or FIFO, and the uid, gid, and
1951 permissions have not changed. */
1953 if ((!isfifo && (statbuf.st_mode & S_IFMT) != S_IFREG) ||
1954 (isfifo && (statbuf.st_mode & S_IFMT) != S_IFIFO))
1956 addr->basic_errno = ERRNO_NOTREGULAR;
1958 string_sprintf("opened mailbox %s is no longer a %s", filename,
1959 isfifo? "named pipe" : "regular file");
1960 addr->special_action = SPECIAL_FREEZE;
1964 if ((ob->check_owner && statbuf.st_uid != uid) ||
1965 (ob->check_group && statbuf.st_gid != gid))
1967 addr->basic_errno = ERRNO_BADUGID;
1969 string_sprintf("opened mailbox %s has wrong uid or gid", filename);
1970 addr->special_action = SPECIAL_FREEZE;
1974 if ((statbuf.st_mode & 07777) != oldmode)
1976 addr->basic_errno = ERRNO_BADMODE;
1977 addr->message = string_sprintf("opened mailbox %s has wrong mode %o "
1978 "(%o expected)", filename, statbuf.st_mode & 07777, mode);
1979 addr->special_action = SPECIAL_FREEZE;
1983 /* If file_format is set, check that the format of the file has not
1984 changed. Error data is set by the testing function. */
1986 if (ob->file_format != NULL &&
1987 check_file_format(fd, tblock, addr) != tblock)
1989 addr->message = US"open mailbox has changed format";
1993 /* The file is OK. Carry on to do the locking. */
1996 /* We now have an open file, and must lock it using fcntl(), flock() or MBX
1997 locking rules if configured to do so. If a lock file is also required, it
1998 was created above and hd was left >= 0. At least one form of locking is
1999 required by the initialization function. If locking fails here, close the
2000 file and go round the loop all over again, after waiting for a bit, unless
2001 blocking locking was used. */
2004 if ((ob->lock_fcntl_timeout > 0) || (ob->lock_flock_timeout > 0))
2005 sleep_before_retry = FALSE;
2007 /* Simple fcntl() and/or flock() locking */
2009 if (!ob->use_mbx_lock && (ob->use_fcntl || ob->use_flock))
2011 if (apply_lock(fd, F_WRLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2012 ob->use_flock, ob->lock_flock_timeout) >= 0) break;
2015 /* MBX locking rules */
2018 else if (ob->use_mbx_lock)
2021 struct stat lstatbuf, statbuf2;
2022 if (apply_lock(fd, F_RDLCK, ob->use_fcntl, ob->lock_fcntl_timeout,
2023 ob->use_flock, ob->lock_flock_timeout) >= 0 &&
2024 fstat(fd, &statbuf) >= 0)
2026 sprintf(CS mbx_lockname, "/tmp/.%lx.%lx", (long)statbuf.st_dev,
2027 (long)statbuf.st_ino);
2030 * 2010-05-29: SECURITY
2031 * Dan Rosenberg reported the presence of a race-condition in the
2032 * original code here. Beware that many systems still allow symlinks
2033 * to be followed in /tmp so an attacker can create a symlink pointing
2034 * elsewhere between a stat and an open, which we should avoid
2037 * It's unfortunate that we can't just use all the heavily debugged
2038 * locking from above.
2040 * Also: remember to mirror changes into exim_lock.c */
2042 /* first leave the old pre-check in place, it provides better
2043 * diagnostics for common cases */
2044 if (Ulstat(mbx_lockname, &statbuf) >= 0)
2046 if ((statbuf.st_mode & S_IFMT) == S_IFLNK)
2048 addr->basic_errno = ERRNO_LOCKFAILED;
2049 addr->message = string_sprintf("symbolic link on MBX lock file %s",
2053 if (statbuf.st_nlink > 1)
2055 addr->basic_errno = ERRNO_LOCKFAILED;
2056 addr->message = string_sprintf("hard link to MBX lock file %s",
2062 /* If we could just declare "we must be the ones who create this
2063 * file" then a hitching post in a subdir would work, since a
2064 * subdir directly in /tmp/ which we create wouldn't follow links
2065 * but this isn't our locking logic, so we can't safely change the
2066 * file existence rules. */
2068 /* On systems which support O_NOFOLLOW, it's the easiest and most
2069 * obviously correct security fix */
2070 mbx_tmp_oflags = O_RDWR | O_CREAT;
2072 mbx_tmp_oflags |= O_NOFOLLOW;
2074 mbx_lockfd = Uopen(mbx_lockname, mbx_tmp_oflags, ob->lockfile_mode);
2077 addr->basic_errno = ERRNO_LOCKFAILED;
2078 addr->message = string_sprintf("failed to open MBX lock file %s :%s",
2079 mbx_lockname, strerror(errno));
2083 if (Ulstat(mbx_lockname, &lstatbuf) < 0)
2085 addr->basic_errno = ERRNO_LOCKFAILED;
2086 addr->message = string_sprintf("attempting to lstat open MBX "
2087 "lock file %s: %s", mbx_lockname, strerror(errno));
2090 if (fstat(mbx_lockfd, &statbuf2) < 0)
2092 addr->basic_errno = ERRNO_LOCKFAILED;
2093 addr->message = string_sprintf("attempting to stat fd of open MBX "
2094 "lock file %s: %s", mbx_lockname, strerror(errno));
2100 * statbuf: if exists, is file which existed prior to opening the
2101 * lockfile, might have been replaced since then
2102 * statbuf2: result of stat'ing the open fd, is what was actually
2104 * lstatbuf: result of lstat'ing the filename immediately after
2105 * the open but there's a race condition again between
2106 * those two steps: before open, symlink to foo, after
2107 * open but before lstat have one of:
2108 * * was no symlink, so is the opened file
2109 * (we created it, no messing possible after that point)
2111 * * symlink elsewhere
2112 * * hardlink elsewhere
2114 * Don't want to compare to device of /tmp because some modern systems
2115 * have regressed to having /tmp be the safe actual filesystem as
2116 * valuable data, so is mostly worthless, unless we assume that *only*
2117 * Linux systems do this and that all Linux has O_NOFOLLOW. Something
2118 * for further consideration.
2119 * No point in doing a readlink on the lockfile as that will always be
2120 * at a different point in time from when we open it, so tells us
2121 * nothing; attempts to clean up and delete after ourselves would risk
2122 * deleting a *third* filename.
2124 if ((statbuf2.st_nlink > 1) ||
2125 (lstatbuf.st_nlink > 1) ||
2126 (!S_ISREG(lstatbuf.st_mode)) ||
2127 (lstatbuf.st_dev != statbuf2.st_dev) ||
2128 (lstatbuf.st_ino != statbuf2.st_ino))
2130 addr->basic_errno = ERRNO_LOCKFAILED;
2131 addr->message = string_sprintf("RACE CONDITION detected: "
2132 "mismatch post-initial-checks between \"%s\" and opened "
2133 "fd lead us to abort!", mbx_lockname);
2137 (void)Uchmod(mbx_lockname, ob->lockfile_mode);
2139 if (apply_lock(mbx_lockfd, F_WRLCK, ob->use_fcntl,
2140 ob->lock_fcntl_timeout, ob->use_flock, ob->lock_flock_timeout) >= 0)
2142 struct stat ostatbuf;
2144 /* This tests for a specific race condition. Ensure that we still
2145 have the same file. */
2147 if (Ulstat(mbx_lockname, &statbuf) == 0 &&
2148 fstat(mbx_lockfd, &ostatbuf) == 0 &&
2149 statbuf.st_dev == ostatbuf.st_dev &&
2150 statbuf.st_ino == ostatbuf.st_ino)
2152 DEBUG(D_transport) debug_printf("MBX lockfile %s changed "
2153 "between creation and locking\n", mbx_lockname);
2156 DEBUG(D_transport) debug_printf("failed to lock %s: %s\n", mbx_lockname,
2158 (void)close(mbx_lockfd);
2163 DEBUG(D_transport) debug_printf("failed to fstat or get read lock on %s: %s\n",
2164 filename, strerror(errno));
2167 #endif /* SUPPORT_MBX */
2169 else break; /* No on-file locking required; break the open/lock loop */
2172 debug_printf("fcntl(), flock(), or MBX locking failed - retrying\n");
2176 use_lstat = TRUE; /* Reset to use lstat first */
2179 /* If a blocking call timed out, break the retry loop if the total time
2180 so far is not less than than retries * interval. Use the larger of the
2181 flock() and fcntl() timeouts. */
2184 (i+1) * ((ob->lock_fcntl_timeout > ob->lock_flock_timeout)?
2185 ob->lock_fcntl_timeout : ob->lock_flock_timeout) >=
2186 ob->lock_retries * ob->lock_interval)
2187 i = ob->lock_retries;
2189 /* Wait a bit before retrying, except when it was a blocked fcntl() or
2190 flock() that caused the problem. */
2192 if (i < ob->lock_retries && sleep_before_retry) sleep(ob->lock_interval);
2195 /* Test for exceeding the maximum number of tries. Either the file remains
2196 locked, or, if we haven't got it open, something is terribly wrong... */
2198 if (i >= ob->lock_retries)
2202 addr->basic_errno = ERRNO_EXISTRACE;
2203 addr->message = string_sprintf("mailbox %s: existence unclear", filename);
2204 addr->special_action = SPECIAL_FREEZE;
2208 addr->basic_errno = ERRNO_LOCKFAILED;
2209 addr->message = string_sprintf("failed to lock mailbox %s (fcntl/flock)",
2215 DEBUG(D_transport) debug_printf("mailbox %s is locked\n", filename);
2217 /* Save access time (for subsequent restoration), modification time (for
2218 restoration if updating fails), size of file (for comsat and for re-setting if
2219 delivery fails in the middle - e.g. for quota exceeded). */
2221 if (fstat(fd, &statbuf) < 0)
2223 addr->basic_errno = errno;
2224 addr->message = string_sprintf("while fstatting opened mailbox %s",
2229 times.actime = statbuf.st_atime;
2230 times.modtime = statbuf.st_mtime;
2231 saved_size = statbuf.st_size;
2232 if (mailbox_size < 0) mailbox_size = saved_size;
2233 mailbox_filecount = 0; /* Not actually relevant for single-file mailbox */
2236 /* Prepare for writing to a new file (as opposed to appending to an old one).
2237 There are several different formats, but there is preliminary stuff concerned
2238 with quotas that applies to all of them. Finding the current size by directory
2239 scanning is expensive; for maildirs some fudges have been invented:
2241 (1) A regex can be used to extract a file size from its name;
2242 (2) If maildir_use_size is set, a maildirsize file is used to cache the
2248 uschar *check_path = path; /* Default quota check path */
2249 const pcre *regex = NULL; /* Regex for file size from file name */
2251 if (!check_creation(string_sprintf("%s/any", path), ob->create_file))
2253 addr->basic_errno = ERRNO_BADCREATE;
2254 addr->message = string_sprintf("tried to create file in %s, but "
2255 "file creation outside the home directory is not permitted", path);
2259 #ifdef SUPPORT_MAILDIR
2260 /* For a maildir delivery, ensure that all the relevant directories exist,
2261 and a maildirfolder file if necessary. */
2263 if (mbformat == mbf_maildir && !maildir_ensure_directories(path, addr,
2264 ob->create_directory, ob->dirmode, ob->maildirfolder_create_regex))
2266 #endif /* SUPPORT_MAILDIR */
2268 /* If we are going to do a quota check, of if maildir_use_size_file is set
2269 for a maildir delivery, compile the regular expression if there is one. We
2270 may also need to adjust the path that is used. We need to do this for
2271 maildir_use_size_file even if the quota is unset, because we still want to
2272 create the file. When maildir support is not compiled,
2273 ob->maildir_use_size_file is always FALSE. */
2275 if (ob->quota_value > 0 || THRESHOLD_CHECK || ob->maildir_use_size_file)
2277 const uschar *error;
2280 /* Compile the regex if there is one. */
2282 if (ob->quota_size_regex != NULL)
2284 regex = pcre_compile(CS ob->quota_size_regex, PCRE_COPT,
2285 (const char **)&error, &offset, NULL);
2288 addr->message = string_sprintf("appendfile: regular expression "
2289 "error: %s at offset %d while compiling %s", error, offset,
2290 ob->quota_size_regex);
2293 DEBUG(D_transport) debug_printf("using regex for file sizes: %s\n",
2294 ob->quota_size_regex);
2297 /* Use an explicitly configured directory if set */
2299 if (ob->quota_directory != NULL)
2301 check_path = expand_string(ob->quota_directory);
2302 if (check_path == NULL)
2304 addr->transport_return = PANIC;
2305 addr->message = string_sprintf("Expansion of \"%s\" (quota_directory "
2306 "name for %s transport) failed: %s", ob->quota_directory,
2307 tblock->name, expand_string_message);
2311 if (check_path[0] != '/')
2313 addr->message = string_sprintf("appendfile: quota_directory name "
2314 "\"%s\" is not absolute", check_path);
2315 addr->basic_errno = ERRNO_NOTABSOLUTE;
2320 #ifdef SUPPORT_MAILDIR
2321 /* Otherwise, if we are handling a maildir delivery, and the directory
2322 contains a file called maildirfolder, this is a maildir++ feature telling
2323 us that this is a sub-directory of the real inbox. We should therefore do
2324 the quota check on the parent directory. Beware of the special case when
2325 the directory name itself ends in a slash. */
2327 else if (mbformat == mbf_maildir)
2329 struct stat statbuf;
2330 if (Ustat(string_sprintf("%s/maildirfolder", path), &statbuf) >= 0)
2332 uschar *new_check_path = string_copy(check_path);
2333 uschar *slash = Ustrrchr(new_check_path, '/');
2339 slash = Ustrrchr(new_check_path, '/');
2344 check_path = new_check_path;
2345 DEBUG(D_transport) debug_printf("maildirfolder file exists: "
2346 "quota check directory changed to %s\n", check_path);
2351 #endif /* SUPPORT_MAILDIR */
2354 /* If we are using maildirsize files, we need to ensure that such a file
2355 exists and, if necessary, recalculate its contents. As a byproduct of this,
2356 we obtain the current size of the maildir. If no quota is to be enforced
2357 (ob->quota_value == 0), we still need the size if a threshold check will
2360 Another regular expression is used to determine which directories inside the
2361 maildir are going to be counted. */
2363 #ifdef SUPPORT_MAILDIR
2364 if (ob->maildir_use_size_file)
2366 const pcre *dir_regex = NULL;
2367 const uschar *error;
2370 if (ob->maildir_dir_regex != NULL)
2372 int check_path_len = Ustrlen(check_path);
2374 dir_regex = pcre_compile(CS ob->maildir_dir_regex, PCRE_COPT,
2375 (const char **)&error, &offset, NULL);
2376 if (dir_regex == NULL)
2378 addr->message = string_sprintf("appendfile: regular expression "
2379 "error: %s at offset %d while compiling %s", error, offset,
2380 ob->maildir_dir_regex);
2385 debug_printf("using regex for maildir directory selection: %s\n",
2386 ob->maildir_dir_regex);
2388 /* Check to see if we are delivering into an ignored directory, that is,
2389 if the delivery path starts with the quota check path, and the rest
2390 of the deliver path matches the regex; if so, set a flag to disable quota
2391 checking and maildirsize updating. */
2393 if (Ustrncmp(path, check_path, check_path_len) == 0)
2395 uschar *s = path + check_path_len;
2396 while (*s == '/') s++;
2397 s = (*s == 0)? US "new" : string_sprintf("%s/new", s);
2398 if (pcre_exec(dir_regex, NULL, CS s, Ustrlen(s), 0, 0, NULL, 0) < 0)
2400 disable_quota = TRUE;
2401 DEBUG(D_transport) debug_printf("delivery directory does not match "
2402 "maildir_quota_directory_regex: disabling quota\n");
2407 /* Quota enforcement; create and check the file. There is some discussion
2408 about whether this should happen if the quota is unset. At present, Exim
2409 always creates the file. If we ever want to change this, uncomment
2410 appropriate lines below, possibly doing a check on some option. */
2412 /* if (???? || ob->quota_value > 0) */
2419 maildirsize_fd = maildir_ensure_sizefile(check_path, ob, regex, dir_regex,
2422 if (maildirsize_fd == -1)
2424 addr->basic_errno = errno;
2425 addr->message = string_sprintf("while opening or reading "
2426 "%s/maildirsize", check_path);
2429 /* can also return -2, which means that the file was removed because of
2430 raciness; but in this case, the size & filecount will still have been
2433 if (mailbox_size < 0) mailbox_size = size;
2434 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2437 /* No quota enforcement; ensure file does *not* exist; calculate size if
2442 * time_t old_latest;
2443 * (void)unlink(CS string_sprintf("%s/maildirsize", check_path));
2444 * if (THRESHOLD_CHECK)
2445 * mailbox_size = maildir_compute_size(check_path, &mailbox_filecount, &old_latest,
2446 * regex, dir_regex, FALSE);
2451 #endif /* SUPPORT_MAILDIR */
2453 /* Otherwise if we are going to do a quota check later on, and the mailbox
2454 size is not set, find the current size of the mailbox. Ditto for the file
2455 count. Note that ob->quota_filecount_value cannot be set without
2456 ob->quota_value being set. */
2458 if (!disable_quota &&
2459 (ob->quota_value > 0 || THRESHOLD_CHECK) &&
2460 (mailbox_size < 0 ||
2461 (mailbox_filecount < 0 && ob->quota_filecount_value > 0)))
2466 debug_printf("quota checks on directory %s\n", check_path);
2467 size = check_dir_size(check_path, &filecount, regex);
2468 if (mailbox_size < 0) mailbox_size = size;
2469 if (mailbox_filecount < 0) mailbox_filecount = filecount;
2472 /* Handle the case of creating a unique file in a given directory (not in
2473 maildir or mailstore format - this is how smail did it). A temporary name is
2474 used to create the file. Later, when it is written, the name is changed to a
2475 unique one. There is no need to lock the file. An attempt is made to create
2476 the directory if it does not exist. */
2478 if (mbformat == mbf_smail)
2481 debug_printf("delivering to new file in %s\n", path);
2482 filename = dataname =
2483 string_sprintf("%s/temp.%d.%s", path, (int)getpid(), primary_hostname);
2484 fd = Uopen(filename, O_WRONLY|O_CREAT, mode);
2485 if (fd < 0 && /* failed to open, and */
2486 (errno != ENOENT || /* either not non-exist */
2487 !ob->create_directory || /* or not allowed to make */
2488 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2489 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2491 addr->basic_errno = errno;
2492 addr->message = string_sprintf("while creating file %s", filename);
2497 #ifdef SUPPORT_MAILDIR
2499 /* Handle the case of a unique file in maildir format. The file is written to
2500 the tmp subdirectory, with a prescribed form of name. */
2502 else if (mbformat == mbf_maildir)
2505 debug_printf("delivering in maildir format in %s\n", path);
2507 nametag = ob->maildir_tag;
2509 /* Check that nametag expands successfully; a hard failure causes a panic
2510 return. The actual expansion for use happens again later, when
2511 $message_size is accurately known. */
2513 if (nametag != NULL && expand_string(nametag) == NULL &&
2514 !expand_string_forcedfail)
2516 addr->transport_return = PANIC;
2517 addr->message = string_sprintf("Expansion of \"%s\" (maildir_tag "
2518 "for %s transport) failed: %s", nametag, tblock->name,
2519 expand_string_message);
2523 /* We ensured the existence of all the relevant directories above. Attempt
2524 to open the temporary file a limited number of times. I think this rather
2525 scary-looking for statement is actually OK. If open succeeds, the loop is
2526 broken; if not, there is a test on the value of i. Get the time again
2527 afresh each time round the loop. Its value goes into a variable that is
2528 checked at the end, to make sure we don't release this process until the
2529 clock has ticked. */
2535 (void)gettimeofday(&msg_tv, NULL);
2536 basename = string_sprintf("%lu.H%luP%lu.%s", msg_tv.tv_sec,
2537 msg_tv.tv_usec, getpid(), primary_hostname);
2539 filename = dataname = string_sprintf("tmp/%s", basename);
2540 newname = string_sprintf("new/%s", basename);
2542 if (Ustat(filename, &statbuf) == 0)
2544 else if (errno == ENOENT)
2546 fd = Uopen(filename, O_WRONLY | O_CREAT | O_EXCL, mode);
2548 DEBUG (D_transport) debug_printf ("open failed for %s: %s\n",
2549 filename, strerror(errno));
2552 /* Too many retries - give up */
2554 if (i >= ob->maildir_retries)
2556 addr->message = string_sprintf ("failed to open %s (%d tr%s)",
2557 filename, i, (i == 1)? "y" : "ies");
2558 addr->basic_errno = errno;
2559 if (errno == errno_quota || errno == ENOSPC)
2560 addr->user_message = US"mailbox is full";
2564 /* Open or stat failed but we haven't tried too many times yet. */
2569 /* Note that we have to ensure the clock has ticked before leaving */
2571 wait_for_tick = TRUE;
2573 /* Why are these here? Put in because they are present in the non-maildir
2574 directory case above. */
2576 (void)Uchown(filename, uid, gid);
2577 (void)Uchmod(filename, mode);
2580 #endif /* SUPPORT_MAILDIR */
2582 #ifdef SUPPORT_MAILSTORE
2584 /* Handle the case of a unique file in mailstore format. First write the
2585 envelope to a temporary file, then open the main file. The unique base name
2586 for the files consists of the message id plus the pid of this delivery
2592 address_item *taddr;
2593 mailstore_basename = string_sprintf("%s/%s-%s", path, message_id,
2594 string_base62((long int)getpid()));
2597 debug_printf("delivering in mailstore format in %s\n", path);
2599 filename = string_sprintf("%s.tmp", mailstore_basename);
2600 newname = string_sprintf("%s.env", mailstore_basename);
2601 dataname = string_sprintf("%s.msg", mailstore_basename);
2603 fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode);
2604 if (fd < 0 && /* failed to open, and */
2605 (errno != ENOENT || /* either not non-exist */
2606 !ob->create_directory || /* or not allowed to make */
2607 !directory_make(NULL, path, ob->dirmode, FALSE) || /* or failed to create dir */
2608 (fd = Uopen(filename, O_WRONLY|O_CREAT|O_EXCL, mode)) < 0)) /* or then failed to open */
2610 addr->basic_errno = errno;
2611 addr->message = string_sprintf("while creating file %s", filename);
2615 /* Why are these here? Put in because they are present in the non-maildir
2616 directory case above. */
2618 (void)Uchown(filename, uid, gid);
2619 (void)Uchmod(filename, mode);
2621 /* Built a C stream from the open file descriptor. */
2623 if ((env_file = fdopen(fd, "wb")) == NULL)
2625 addr->basic_errno = errno;
2626 addr->transport_return = PANIC;
2627 addr->message = string_sprintf("fdopen of %s ("
2628 "for %s transport) failed", filename, tblock->name);
2634 /* Write the envelope file, then close it. */
2636 if (ob->mailstore_prefix != NULL)
2638 uschar *s = expand_string(ob->mailstore_prefix);
2641 if (!expand_string_forcedfail)
2643 addr->transport_return = PANIC;
2644 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2645 "prefix for %s transport) failed: %s", ob->mailstore_prefix,
2646 tblock->name, expand_string_message);
2647 (void)fclose(env_file);
2655 fprintf(env_file, "%s", CS s);
2656 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2660 fprintf(env_file, "%s\n", sender_address);
2662 for (taddr = addr; taddr!= NULL; taddr = taddr->next)
2663 fprintf(env_file, "%s@%s\n", taddr->local_part, taddr->domain);
2665 if (ob->mailstore_suffix != NULL)
2667 uschar *s = expand_string(ob->mailstore_suffix);
2670 if (!expand_string_forcedfail)
2672 addr->transport_return = PANIC;
2673 addr->message = string_sprintf("Expansion of \"%s\" (mailstore "
2674 "suffix for %s transport) failed: %s", ob->mailstore_suffix,
2675 tblock->name, expand_string_message);
2676 (void)fclose(env_file);
2684 fprintf(env_file, "%s", CS s);
2685 if (n == 0 || s[n-1] != '\n') fprintf(env_file, "\n");
2689 if (fclose(env_file) != 0)
2691 addr->basic_errno = errno;
2692 addr->message = string_sprintf("while closing %s", filename);
2697 DEBUG(D_transport) debug_printf("Envelope file %s written\n", filename);
2699 /* Now open the data file, and ensure that it has the correct ownership and
2702 fd = Uopen(dataname, O_WRONLY|O_CREAT|O_EXCL, mode);
2705 addr->basic_errno = errno;
2706 addr->message = string_sprintf("while creating file %s", dataname);
2710 (void)Uchown(dataname, uid, gid);
2711 (void)Uchmod(dataname, mode);
2714 #endif /* SUPPORT_MAILSTORE */
2717 /* In all cases of writing to a new file, ensure that the file which is
2718 going to be renamed has the correct ownership and mode. */
2720 (void)Uchown(filename, uid, gid);
2721 (void)Uchmod(filename, mode);
2725 /* At last we can write the message to the file, preceded by any configured
2726 prefix line, and followed by any configured suffix line. If there are any
2727 writing errors, we must defer. */
2729 DEBUG(D_transport) debug_printf("writing to file %s\n", dataname);
2734 /* If there is a local quota setting, check that we are not going to exceed it
2735 with this message if quota_is_inclusive is set; if it is not set, the check
2736 is for the mailbox already being over quota (i.e. the current message is not
2737 included in the check). */
2739 if (!disable_quota && ob->quota_value > 0)
2743 debug_printf("Exim quota = " OFF_T_FMT " old size = " OFF_T_FMT
2744 " this message = %d (%sincluded)\n",
2745 ob->quota_value, mailbox_size, message_size,
2746 ob->quota_is_inclusive? "" : "not ");
2747 debug_printf(" file count quota = %d count = %d\n",
2748 ob->quota_filecount_value, mailbox_filecount);
2750 if (mailbox_size + (ob->quota_is_inclusive? message_size:0) > ob->quota_value)
2752 DEBUG(D_transport) debug_printf("mailbox quota exceeded\n");
2754 errno = ERRNO_EXIMQUOTA;
2756 else if (ob->quota_filecount_value > 0 &&
2757 mailbox_filecount + (ob->quota_is_inclusive ? 1:0) >
2758 ob->quota_filecount_value)
2760 DEBUG(D_transport) debug_printf("mailbox file count quota exceeded\n");
2762 errno = ERRNO_EXIMQUOTA;
2763 filecount_msg = US" filecount";
2767 /* If we are writing in MBX format, what we actually do is to write the message
2768 to a temporary file, and then copy it to the real file once we know its size.
2769 This is the most straightforward way of getting the correct length in the
2770 separator line. So, what we do here is to save the real file descriptor, and
2771 replace it with one for a temporary file. The temporary file gets unlinked once
2772 opened, so that it goes away on closure. */
2775 if (yield == OK && ob->mbx_format)
2777 temp_file = tmpfile();
2778 if (temp_file == NULL)
2780 addr->basic_errno = errno;
2781 addr->message = US"while setting up temporary file";
2786 fd = fileno(temp_file);
2787 DEBUG(D_transport) debug_printf("writing to temporary file\n");
2789 #endif /* SUPPORT_MBX */
2791 /* Zero the count of bytes written. It is incremented by the transport_xxx()
2794 transport_count = 0;
2795 transport_newlines = 0;
2797 /* Write any configured prefix text first */
2799 if (yield == OK && ob->message_prefix != NULL && ob->message_prefix[0] != 0)
2801 uschar *prefix = expand_string(ob->message_prefix);
2804 errno = ERRNO_EXPANDFAIL;
2805 addr->transport_return = PANIC;
2806 addr->message = string_sprintf("Expansion of \"%s\" (prefix for %s "
2807 "transport) failed", ob->message_prefix, tblock->name);
2810 else if (!transport_write_string(fd, "%s", prefix)) yield = DEFER;
2813 /* If the use_bsmtp option is on, we need to write SMTP prefix information. The
2814 various different values for batching are handled outside; if there is more
2815 than one address available here, all must be included. If any address is a
2816 file, use its parent in the RCPT TO. */
2818 if (yield == OK && ob->use_bsmtp)
2820 transport_count = 0;
2821 transport_newlines = 0;
2822 if (ob->use_crlf) cr = US"\r";
2823 if (!transport_write_string(fd, "MAIL FROM:<%s>%s\n", return_path, cr))
2828 transport_newlines++;
2829 for (a = addr; a != NULL; a = a->next)
2831 address_item *b = testflag(a, af_pfr)? a->parent: a;
2832 if (!transport_write_string(fd, "RCPT TO:<%s>%s\n",
2833 transport_rcpt_address(b, tblock->rcpt_include_affixes), cr))
2834 { yield = DEFER; break; }
2835 transport_newlines++;
2837 if (yield == OK && !transport_write_string(fd, "DATA%s\n", cr))
2840 transport_newlines++;
2844 /* Now the message itself. The options for transport_write_message were set up
2845 at initialization time. */
2849 if (!transport_write_message(addr, fd, ob->options, 0, tblock->add_headers,
2850 tblock->remove_headers, ob->check_string, ob->escape_string,
2851 tblock->rewrite_rules, tblock->rewrite_existflags))
2855 /* Now a configured suffix. */
2857 if (yield == OK && ob->message_suffix != NULL && ob->message_suffix[0] != 0)
2859 uschar *suffix = expand_string(ob->message_suffix);
2862 errno = ERRNO_EXPANDFAIL;
2863 addr->transport_return = PANIC;
2864 addr->message = string_sprintf("Expansion of \"%s\" (suffix for %s "
2865 "transport) failed", ob->message_suffix, tblock->name);
2868 else if (!transport_write_string(fd, "%s", suffix)) yield = DEFER;
2871 /* If batch smtp, write the terminating dot. */
2873 if (yield == OK && ob->use_bsmtp ) {
2874 if(!transport_write_string(fd, ".%s\n", cr)) yield = DEFER;
2875 else transport_newlines++;
2878 /* If MBX format is being used, all that writing was to the temporary file.
2879 However, if there was an earlier failure (Exim quota exceeded, for example),
2880 the temporary file won't have got opened - and no writing will have been done.
2881 If writing was OK, we restore the fd, and call a function that copies the
2882 message in MBX format into the real file. Otherwise use the temporary name in
2886 if (temp_file != NULL && ob->mbx_format)
2893 transport_count = 0; /* Reset transport count for actual write */
2894 /* No need to reset transport_newlines as we're just using a block copy
2895 * routine so the number won't be affected */
2896 yield = copy_mbx_message(fd, fileno(temp_file), saved_size);
2898 else if (errno >= 0) dataname = US"temporary file";
2900 /* Preserve errno while closing the temporary file. */
2902 mbx_save_errno = errno;
2903 (void)fclose(temp_file);
2904 errno = mbx_save_errno;
2906 #endif /* SUPPORT_MBX */
2908 /* Force out the remaining data to check for any errors; some OS don't allow
2909 fsync() to be called for a FIFO. */
2911 if (yield == OK && !isfifo && EXIMfsync(fd) < 0) yield = DEFER;
2913 /* Update message_size and message_linecount to the accurate count of bytes
2914 written, including added headers. Note; we subtract 1 from message_linecount as
2915 this variable doesn't count the new line between the header and the body of the
2918 message_size = transport_count;
2919 message_linecount = transport_newlines - 1;
2921 /* If using a maildir++ quota file, add this message's size to it, and
2922 close the file descriptor, except when the quota has been disabled because we
2923 are delivering into an uncounted folder. */
2925 #ifdef SUPPORT_MAILDIR
2928 if (yield == OK && maildirsize_fd >= 0)
2929 maildir_record_length(maildirsize_fd, message_size);
2930 maildir_save_errno = errno; /* Preserve errno while closing the file */
2931 if (maildirsize_fd >= 0)
2932 (void)close(maildirsize_fd);
2933 errno = maildir_save_errno;
2935 #endif /* SUPPORT_MAILDIR */
2937 /* If there is a quota warning threshold and we are have crossed it with this
2938 message, set the SPECIAL_WARN flag in the address, to cause a warning message
2941 if (!disable_quota && THRESHOLD_CHECK)
2943 off_t threshold = ob->quota_warn_threshold_value;
2944 if (ob->quota_warn_threshold_is_percent)
2945 threshold = (off_t)(((double)ob->quota_value * threshold) / 100);
2947 debug_printf("quota = " OFF_T_FMT
2948 " threshold = " OFF_T_FMT
2949 " old size = " OFF_T_FMT
2950 " message size = %d\n",
2951 ob->quota_value, threshold, mailbox_size,
2953 if (mailbox_size <= threshold && mailbox_size + message_size > threshold)
2954 addr->special_action = SPECIAL_WARN;
2956 /******* You might think that the test ought to be this:
2958 * if (ob->quota_value > 0 && threshold > 0 && mailbox_size > 0 &&
2959 * mailbox_size <= threshold && mailbox_size + message_size > threshold)
2961 * (indeed, I was sent a patch with that in). However, it is possible to
2962 * have a warning threshold without actually imposing a quota, and I have
2963 * therefore kept Exim backwards compatible.
2968 /* Handle error while writing the file. Control should come here directly after
2969 the error, with the reason in errno. In the case of expansion failure in prefix
2970 or suffix, it will be ERRNO_EXPANDFAIL. */
2974 addr->special_action = SPECIAL_NONE; /* Cancel any quota warning */
2976 /* Save the error number. If positive, it will ultimately cause a strerror()
2977 call to generate some text. */
2979 addr->basic_errno = errno;
2981 /* For system or Exim quota excession, or disk full, set more_errno to the
2982 time since the file was last read. If delivery was into a directory, the
2983 time since last read logic is not relevant, in general. However, for maildir
2984 deliveries we can approximate it by looking at the last modified time of the
2985 "new" subdirectory. Since Exim won't be adding new messages, a change to the
2986 "new" subdirectory implies that an MUA has moved a message from there to the
2989 if (errno == errno_quota || errno == ERRNO_EXIMQUOTA || errno == ENOSPC)
2991 addr->more_errno = 0;
2992 if (!isdirectory) addr->more_errno = (int)(time(NULL) - times.actime);
2994 #ifdef SUPPORT_MAILDIR
2995 else if (mbformat == mbf_maildir)
2997 struct stat statbuf;
2998 if (Ustat("new", &statbuf) < 0)
3000 DEBUG(D_transport) debug_printf("maildir quota exceeded: "
3001 "stat error %d for \"new\": %s\n", errno, strerror(errno));
3003 else /* Want a repeatable time when in test harness */
3005 addr->more_errno = running_in_test_harness? 10 :
3006 (int)time(NULL) - statbuf.st_mtime;
3009 debug_printf("maildir: time since \"new\" directory modified = %s\n",
3010 readconf_printtime(addr->more_errno));
3012 #endif /* SUPPORT_MAILDIR */
3015 /* Handle system quota excession. Add an explanatory phrase for the error
3016 message, since some systems don't have special quota-excession errors,
3017 and on those that do, "quota" doesn't always mean anything to the user. */
3019 if (errno == errno_quota)
3022 addr->message = string_sprintf("mailbox is full "
3023 "(quota exceeded while writing to file %s)", filename);
3025 addr->message = string_sprintf("mailbox is full");
3027 addr->user_message = US"mailbox is full";
3028 DEBUG(D_transport) debug_printf("System quota exceeded for %s%s%s\n",
3030 isdirectory? US"" : US": time since file read = ",
3031 isdirectory? US"" : readconf_printtime(addr->more_errno));
3034 /* Handle Exim's own quota-imposition */
3036 else if (errno == ERRNO_EXIMQUOTA)
3038 addr->message = string_sprintf("mailbox is full "
3039 "(MTA-imposed%s quota exceeded while writing to %s)", filecount_msg,
3041 addr->user_message = US"mailbox is full";
3042 DEBUG(D_transport) debug_printf("Exim%s quota exceeded for %s%s%s\n",
3043 filecount_msg, dataname,
3044 isdirectory? US"" : US": time since file read = ",
3045 isdirectory? US"" : readconf_printtime(addr->more_errno));
3048 /* Handle a process failure while writing via a filter; the return
3049 from child_close() is in more_errno. */
3051 else if (errno == ERRNO_FILTER_FAIL)
3054 addr->message = string_sprintf("transport filter process failed (%d) "
3055 "while writing to %s%s", addr->more_errno, dataname,
3056 (addr->more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
3059 /* Handle failure to expand header changes */
3061 else if (errno == ERRNO_CHHEADER_FAIL)
3065 string_sprintf("failed to expand headers_add or headers_remove while "
3066 "writing to %s: %s", dataname, expand_string_message);
3069 /* Handle failure to complete writing of a data block */
3071 else if (errno == ERRNO_WRITEINCOMPLETE)
3073 addr->message = string_sprintf("failed to write data block while "
3074 "writing to %s", dataname);
3077 /* Handle length mismatch on MBX copying */
3080 else if (errno == ERRNO_MBXLENGTH)
3082 addr->message = string_sprintf("length mismatch while copying MBX "
3083 "temporary file to %s", dataname);
3085 #endif /* SUPPORT_MBX */
3087 /* For other errors, a general-purpose explanation, if the message is
3090 else if (addr->message == NULL)
3091 addr->message = string_sprintf("error while writing to %s", dataname);
3093 /* For a file, reset the file size to what it was before we started, leaving
3094 the last modification time unchanged, so it will get reset also. All systems
3095 investigated so far have ftruncate(), whereas not all have the F_FREESP
3096 fcntl() call (BSDI & FreeBSD do not). */
3098 if (!isdirectory) (void)ftruncate(fd, saved_size);
3101 /* Handle successful writing - we want the modification time to be now for
3102 appended files. Remove the default backstop error number. For a directory, now
3103 is the time to rename the file with a unique name. As soon as such a name
3104 appears it may get used by another process, so we close the file first and
3105 check that all is well. */
3109 times.modtime = time(NULL);
3110 addr->basic_errno = 0;
3112 /* Handle the case of writing to a new file in a directory. This applies
3113 to all single-file formats - maildir, mailstore, and "smail format". */
3117 if (fstat(fd, &statbuf) < 0)
3119 addr->basic_errno = errno;
3120 addr->message = string_sprintf("while fstatting opened message file %s",
3125 else if (close(fd) < 0)
3127 addr->basic_errno = errno;
3128 addr->message = string_sprintf("close() error for %s",
3129 (ob->mailstore_format)? dataname : filename);
3133 /* File is successfully written and closed. Arrange to rename it. For the
3134 different kinds of single-file delivery, some games can be played with the
3135 name. The message size is by this time set to the accurate value so that
3136 its value can be used in expansions. */
3140 uschar *renamename = newname;
3143 DEBUG(D_transport) debug_printf("renaming temporary file\n");
3145 /* If there is no rename name set, we are in a non-maildir, non-mailstore
3146 situation. The name is built by expanding the directory_file option, and
3147 we make the inode number available for use in this. The expansion was
3148 checked for syntactic validity above, before we wrote the file.
3150 We have to be careful here, in case the file name exists. (In the other
3151 cases, the names used are constructed to be unique.) The rename()
3152 function just replaces an existing file - we don't want that! So instead
3153 of calling rename(), we must use link() and unlink().
3155 In this case, if the link fails because of an existing file, we wait
3156 for one second and try the expansion again, to see if it produces a
3157 different value. Do this up to 5 times unless the name stops changing.
3158 This makes it possible to build values that are based on the time, and
3159 still cope with races from multiple simultaneous deliveries. */
3161 if (newname == NULL)
3165 uschar *old_renameleaf = US"";
3167 for (i = 0; ; sleep(1), i++)
3169 deliver_inode = statbuf.st_ino;
3170 renameleaf = expand_string(ob->dirfilename);
3173 if (renameleaf == NULL)
3175 addr->transport_return = PANIC;
3176 addr->message = string_sprintf("Expansion of \"%s\" "
3177 "(directory_file for %s transport) failed: %s",
3178 ob->dirfilename, tblock->name, expand_string_message);
3182 renamename = string_sprintf("%s/%s", path, renameleaf);
3183 if (Ulink(filename, renamename) < 0)
3185 DEBUG(D_transport) debug_printf("link failed: %s\n",
3187 if (errno != EEXIST || i >= 4 ||
3188 Ustrcmp(renameleaf, old_renameleaf) == 0)
3190 addr->basic_errno = errno;
3191 addr->message = string_sprintf("while renaming %s as %s",
3192 filename, renamename);
3196 old_renameleaf = renameleaf;
3197 DEBUG(D_transport) debug_printf("%s exists - trying again\n",
3206 } /* re-expand loop */
3207 } /* not mailstore or maildir */
3209 /* For maildir and mailstore formats, the new name was created earlier,
3210 except that for maildir, there is the possibility of adding a "tag" on
3211 the end of the name by expanding the value of nametag. This usually
3212 includes a reference to the message size. The expansion of nametag was
3213 checked above, before the file was opened. It either succeeded, or
3214 provoked a soft failure. So any failure here can be treated as soft.
3215 Ignore non-printing characters and / and put a colon at the start if the
3216 first character is alphanumeric. */
3220 if (nametag != NULL)
3222 uschar *iptr = expand_string(nametag);
3225 uschar *etag = store_get(Ustrlen(iptr) + 2);
3226 uschar *optr = etag;
3229 if (mac_isgraph(*iptr) && *iptr != '/')
3231 if (optr == etag && isalnum(*iptr)) *optr++ = ':';
3237 renamename = string_sprintf("%s%s", newname, etag);
3241 /* Do the rename. If the name is too long and a tag exists, try again
3244 if (Urename(filename, renamename) < 0 &&
3245 (nametag == NULL || errno != ENAMETOOLONG ||
3246 (renamename = newname, Urename(filename, renamename) < 0)))
3248 addr->basic_errno = errno;
3249 addr->message = string_sprintf("while renaming %s as %s",
3250 filename, renamename);
3254 /* Rename succeeded */
3258 DEBUG(D_transport) debug_printf("renamed %s as %s\n", filename,
3260 filename = dataname = NULL; /* Prevents attempt to unlink at end */
3262 } /* maildir or mailstore */
3263 } /* successful write + close */
3265 } /* write success */
3268 /* For a file, restore the last access time (atime), and set the modification
3269 time as required - changed if write succeeded, unchanged if not. */
3271 if (!isdirectory) utime(CS filename, ×);
3273 /* Notify comsat if configured to do so. It only makes sense if the configured
3274 file is the one that the comsat daemon knows about. */
3276 if (ob->notify_comsat && yield == OK && deliver_localpart != NULL)
3277 notify_comsat(deliver_localpart, saved_size);
3279 /* Pass back the final return code in the address structure */
3282 debug_printf("appendfile yields %d with errno=%d more_errno=%d\n",
3283 yield, addr->basic_errno, addr->more_errno);
3285 addr->transport_return = yield;
3287 /* Close the file, which will release the fcntl lock. For a directory write it
3288 is closed above, except in cases of error which goto RETURN, when we also need
3289 to remove the original file(s). For MBX locking, if all has gone well, before
3290 closing the file, see if we can get an exclusive lock on it, in which case we
3291 can unlink the /tmp lock file before closing it. This is always a non-blocking
3292 lock; there's no need to wait if we can't get it. If everything has gone right
3293 but close fails, defer the message. Then unlink the lock file, if present. This
3294 point in the code is jumped to from a number of places when errors are
3295 detected, in order to get the file closed and the lock file tidied away. */
3300 if (mbx_lockfd >= 0)
3302 if (yield == OK && apply_lock(fd, F_WRLCK, ob->use_fcntl, 0,
3303 ob->use_flock, 0) >= 0)
3306 debug_printf("unlinking MBX lock file %s\n", mbx_lockname);
3307 Uunlink(mbx_lockname);
3309 (void)close(mbx_lockfd);
3311 #endif /* SUPPORT_MBX */
3313 if (fd >= 0 && close(fd) < 0 && yield == OK)
3315 addr->basic_errno = errno;
3316 addr->message = string_sprintf("while closing %s", filename);
3317 addr->transport_return = DEFER;
3320 if (hd >= 0) Uunlink(lockname);
3322 /* We get here with isdirectory and filename set only in error situations. */
3324 if (isdirectory && filename != NULL)
3327 if (dataname != filename) Uunlink(dataname);
3330 /* If wait_for_tick is TRUE, we have done a delivery where the uniqueness of a
3331 file name relies on time + pid. We must not allow the process to finish until
3332 the clock has move on by at least one microsecond. Usually we expect this
3333 already to be the case, but machines keep getting faster... */
3335 if (wait_for_tick) exim_wait_tick(&msg_tv, 1);
3337 /* A return of FALSE means that if there was an error, a common error was
3338 put in the first address of a batch. */
3343 /* End of transport/appendfile.c */