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ea49d0e1 | 1 | /* $Cambridge: exim/src/src/retry.c,v 1.6 2006/02/08 14:28:51 ph10 Exp $ */ |
059ec3d9 PH |
2 | |
3 | /************************************************* | |
4 | * Exim - an Internet mail transport agent * | |
5 | *************************************************/ | |
6 | ||
d7d7b7b9 | 7 | /* Copyright (c) University of Cambridge 1995 - 2006 */ |
059ec3d9 PH |
8 | /* See the file NOTICE for conditions of use and distribution. */ |
9 | ||
10 | /* Functions concerned with retrying unsuccessful deliveries. */ | |
11 | ||
12 | ||
13 | #include "exim.h" | |
14 | ||
15 | ||
16 | ||
17 | /************************************************* | |
18 | * Check the ultimate address timeout * | |
19 | *************************************************/ | |
20 | ||
21 | /* This function tests whether a message has been on the queue longer than | |
22 | the maximum retry time for a particular host. | |
23 | ||
24 | Arguments: | |
25 | host_key the key to look up a host retry rule | |
26 | domain the domain to look up a domain retry rule | |
27 | basic_errno a specific error number, or zero if none | |
28 | more_errno additional data for the error | |
29 | now the time | |
30 | ||
31 | Returns: TRUE if the ultimate timeout has been reached | |
32 | */ | |
33 | ||
34 | static BOOL | |
35 | ultimate_address_timeout(uschar *host_key, uschar *domain, int basic_errno, | |
36 | int more_errno, time_t now) | |
37 | { | |
38 | BOOL address_timeout = TRUE; /* no rule => timed out */ | |
39 | ||
40 | retry_config *retry = | |
41 | retry_find_config(host_key+2, domain, basic_errno, more_errno); | |
42 | ||
43 | if (retry != NULL && retry->rules != NULL) | |
44 | { | |
45 | retry_rule *last_rule; | |
46 | for (last_rule = retry->rules; | |
47 | last_rule->next != NULL; | |
48 | last_rule = last_rule->next); | |
ea49d0e1 PH |
49 | DEBUG(D_transport|D_retry) |
50 | debug_printf("now=%d received_time=%d diff=%d timeout=%d\n", | |
51 | (int)now, received_time, (int)(now - received_time), | |
52 | last_rule->timeout); | |
059ec3d9 PH |
53 | address_timeout = (now - received_time > last_rule->timeout); |
54 | } | |
ea49d0e1 PH |
55 | else |
56 | { | |
57 | DEBUG(D_transport|D_retry) | |
58 | debug_printf("no retry rule found: assume timed out\n"); | |
59 | } | |
059ec3d9 PH |
60 | |
61 | return address_timeout; | |
62 | } | |
63 | ||
64 | ||
65 | ||
66 | /************************************************* | |
67 | * Set status of a host+address item * | |
68 | *************************************************/ | |
69 | ||
70 | /* This function is passed a host_item which contains a host name and an | |
71 | IP address string. Its job is to set the status of the address if it is not | |
72 | already set (indicated by hstatus_unknown). The possible values are: | |
73 | ||
74 | hstatus_usable the address is not listed in the unusable tree, and does | |
75 | not have a retry record, OR the time is past the next | |
76 | try time, OR the message has been on the queue for more | |
77 | than the maximum retry time for a failing host | |
78 | ||
79 | hstatus_unusable the address is listed in the unusable tree, or does have | |
80 | a retry record, and the time is not yet at the next retry | |
81 | time. | |
82 | ||
83 | hstatus_unusable_expired as above, but also the retry time has expired | |
84 | for this address. | |
85 | ||
86 | The reason a delivery is permitted when a message has been around for a very | |
87 | long time is to allow the ultimate address timeout to operate after a delivery | |
88 | failure. Otherwise some messages may stick around without being tried for too | |
89 | long. | |
90 | ||
91 | If a host retry record is retrieved from the hints database, the time of last | |
92 | trying is filled into the last_try field of the host block. If a host is | |
93 | generally usable, a check is made to see if there is a retry delay on this | |
94 | specific message at this host. | |
95 | ||
96 | If a non-standard port is being used, it is added to the retry key. | |
97 | ||
98 | Arguments: | |
99 | domain the address domain | |
100 | host pointer to a host item | |
101 | portstring "" for standard port, ":xxxx" for a non-standard port | |
102 | include_ip_address TRUE to include the address in the key - this is | |
103 | usual, but sometimes is not wanted | |
104 | retry_host_key where to put a pointer to the key for the host-specific | |
105 | retry record, if one is read and the host is usable | |
106 | retry_message_key where to put a pointer to the key for the message+host | |
107 | retry record, if one is read and the host is usable | |
108 | ||
109 | Returns: TRUE if the host has expired but is usable because | |
110 | its retry time has come | |
111 | */ | |
112 | ||
113 | BOOL | |
114 | retry_check_address(uschar *domain, host_item *host, uschar *portstring, | |
115 | BOOL include_ip_address, uschar **retry_host_key, uschar **retry_message_key) | |
116 | { | |
117 | BOOL yield = FALSE; | |
118 | time_t now = time(NULL); | |
119 | uschar *host_key, *message_key; | |
120 | open_db dbblock; | |
121 | open_db *dbm_file; | |
122 | tree_node *node; | |
123 | dbdata_retry *host_retry_record, *message_retry_record; | |
124 | ||
125 | *retry_host_key = *retry_message_key = NULL; | |
126 | ||
127 | DEBUG(D_transport|D_retry) debug_printf("checking status of %s\n", host->name); | |
128 | ||
129 | /* Do nothing if status already set; otherwise initialize status as usable. */ | |
130 | ||
131 | if (host->status != hstatus_unknown) return FALSE; | |
132 | host->status = hstatus_usable; | |
133 | ||
134 | /* Generate the host key for the unusable tree and the retry database. Ensure | |
135 | host names are lower cased (that's what %S does). */ | |
136 | ||
137 | host_key = include_ip_address? | |
138 | string_sprintf("T:%S:%s%s", host->name, host->address, portstring) : | |
139 | string_sprintf("T:%S%s", host->name, portstring); | |
140 | ||
141 | /* Generate the message-specific key */ | |
142 | ||
143 | message_key = string_sprintf("%s:%s", host_key, message_id); | |
144 | ||
145 | /* Search the tree of unusable IP addresses. This is filled in when deliveries | |
146 | fail, because the retry database itself is not updated until the end of all | |
147 | deliveries (so as to do it all in one go). The tree records addresses that have | |
148 | become unusable during this delivery process (i.e. those that will get put into | |
149 | the retry database when it is updated). */ | |
150 | ||
151 | node = tree_search(tree_unusable, host_key); | |
152 | if (node != NULL) | |
153 | { | |
154 | DEBUG(D_transport|D_retry) debug_printf("found in tree of unusables\n"); | |
155 | host->status = (node->data.val > 255)? | |
156 | hstatus_unusable_expired : hstatus_unusable; | |
157 | host->why = node->data.val & 255; | |
158 | return FALSE; | |
159 | } | |
160 | ||
161 | /* Open the retry database, giving up if there isn't one. Otherwise, search for | |
162 | the retry records, and then close the database again. */ | |
163 | ||
164 | if ((dbm_file = dbfn_open(US"retry", O_RDONLY, &dbblock, FALSE)) == NULL) | |
165 | { | |
166 | DEBUG(D_deliver|D_retry|D_hints_lookup) | |
167 | debug_printf("no retry data available\n"); | |
168 | return FALSE; | |
169 | } | |
170 | host_retry_record = dbfn_read(dbm_file, host_key); | |
171 | message_retry_record = dbfn_read(dbm_file, message_key); | |
172 | dbfn_close(dbm_file); | |
173 | ||
174 | /* Ignore the data if it is too old - too long since it was written */ | |
175 | ||
176 | if (host_retry_record == NULL) | |
177 | { | |
178 | DEBUG(D_transport|D_retry) debug_printf("no host retry record\n"); | |
179 | } | |
180 | else if (now - host_retry_record->time_stamp > retry_data_expire) | |
181 | { | |
182 | host_retry_record = NULL; | |
183 | DEBUG(D_transport|D_retry) debug_printf("host retry record too old\n"); | |
184 | } | |
185 | ||
186 | if (message_retry_record == NULL) | |
187 | { | |
188 | DEBUG(D_transport|D_retry) debug_printf("no message retry record\n"); | |
189 | } | |
190 | else if (now - message_retry_record->time_stamp > retry_data_expire) | |
191 | { | |
192 | message_retry_record = NULL; | |
193 | DEBUG(D_transport|D_retry) debug_printf("message retry record too old\n"); | |
194 | } | |
195 | ||
196 | /* If there's a host-specific retry record, check for reaching the retry | |
197 | time (or forcing). If not, and the host is not expired, check for the message | |
198 | having been around for longer than the maximum retry time for this host or | |
199 | address. Allow the delivery if it has. Otherwise set the appropriate unusable | |
200 | flag and return FALSE. Otherwise arrange to return TRUE if this is an expired | |
201 | host. */ | |
202 | ||
203 | if (host_retry_record != NULL) | |
204 | { | |
205 | *retry_host_key = host_key; | |
206 | ||
207 | /* We have not reached the next try time. Check for the ultimate address | |
208 | timeout if the host has not expired. */ | |
209 | ||
210 | if (now < host_retry_record->next_try && !deliver_force) | |
211 | { | |
212 | DEBUG(D_transport|D_retry) | |
213 | debug_printf("host retry time not reached: checking ultimate address " | |
214 | "timeout\n"); | |
215 | ||
216 | if (!host_retry_record->expired && | |
217 | ultimate_address_timeout(host_key, domain, | |
218 | host_retry_record->basic_errno, host_retry_record->more_errno, now)) | |
219 | { | |
220 | DEBUG(D_transport|D_retry) | |
221 | debug_printf("on queue longer than maximum retry for " | |
222 | "address - allowing delivery\n"); | |
223 | return FALSE; | |
224 | } | |
225 | ||
226 | /* We have not hit the ultimate address timeout; host is unusable. */ | |
227 | ||
228 | host->status = (host_retry_record->expired)? | |
229 | hstatus_unusable_expired : hstatus_unusable; | |
230 | host->why = hwhy_retry; | |
231 | host->last_try = host_retry_record->last_try; | |
232 | return FALSE; | |
233 | } | |
234 | ||
235 | /* Host is usable; set return TRUE if expired. */ | |
236 | ||
237 | yield = host_retry_record->expired; | |
238 | } | |
239 | ||
240 | /* It's OK to try the host. If there's a message-specific retry record, check | |
241 | for reaching its retry time (or forcing). If not, mark the host unusable, | |
242 | unless the ultimate address timeout has been reached. */ | |
243 | ||
244 | if (message_retry_record != NULL) | |
245 | { | |
246 | *retry_message_key = message_key; | |
247 | if (now < message_retry_record->next_try && !deliver_force) | |
248 | { | |
249 | DEBUG(D_transport|D_retry) | |
250 | debug_printf("host+message retry time not reached: checking ultimate " | |
251 | "address timeout\n"); | |
252 | if (!ultimate_address_timeout(host_key, domain, 0, 0, now)) | |
253 | { | |
254 | host->status = hstatus_unusable; | |
255 | host->why = hwhy_retry; | |
256 | } | |
257 | else | |
258 | { | |
259 | DEBUG(D_transport|D_retry) | |
260 | debug_printf("on queue longer than maximum retry for " | |
261 | "address - allowing delivery\n"); | |
262 | } | |
263 | return FALSE; | |
264 | } | |
265 | } | |
266 | ||
267 | return yield; | |
268 | } | |
269 | ||
270 | ||
271 | ||
272 | ||
273 | /************************************************* | |
274 | * Add a retry item to an address * | |
275 | *************************************************/ | |
276 | ||
277 | /* Retry items are chained onto an address when it is deferred either by router | |
278 | or by a transport, or if it succeeds or fails and there was a previous retry | |
279 | item that now needs to be deleted. Sometimes there can be both kinds of item: | |
280 | for example, if routing was deferred but then succeeded, and delivery then | |
281 | deferred. In that case there is a delete item for the routing retry, and an | |
282 | updating item for the delivery. | |
283 | ||
284 | (But note that that is only visible at the outer level, because in remote | |
285 | delivery subprocesses, the address starts "clean", with no retry items carried | |
286 | in.) | |
287 | ||
288 | These items are used at the end of a delivery attempt to update the retry | |
289 | database. The keys start R: for routing delays and T: for transport delays. | |
290 | ||
291 | Arguments: | |
292 | addr the address block onto which to hang the item | |
293 | key the retry key | |
294 | flags delete, host, and message flags, copied into the block | |
295 | ||
296 | Returns: nothing | |
297 | */ | |
298 | ||
299 | void | |
300 | retry_add_item(address_item *addr, uschar *key, int flags) | |
301 | { | |
302 | retry_item *rti = store_get(sizeof(retry_item)); | |
303 | rti->next = addr->retries; | |
304 | addr->retries = rti; | |
305 | rti->key = key; | |
306 | rti->basic_errno = addr->basic_errno; | |
307 | rti->more_errno = addr->more_errno; | |
308 | rti->message = addr->message; | |
309 | rti->flags = flags; | |
310 | ||
311 | DEBUG(D_transport|D_retry) | |
312 | { | |
313 | int letter = rti->more_errno & 255; | |
314 | debug_printf("added retry item for %s: errno=%d more_errno=", rti->key, | |
315 | rti->basic_errno); | |
316 | if (letter == 'A' || letter == 'M') | |
317 | debug_printf("%d,%c", (rti->more_errno >> 8) & 255, letter); | |
318 | else | |
319 | debug_printf("%d", rti->more_errno); | |
320 | debug_printf(" flags=%d\n", flags); | |
321 | } | |
322 | } | |
323 | ||
324 | ||
325 | ||
326 | /************************************************* | |
327 | * Find retry configuration data * | |
328 | *************************************************/ | |
329 | ||
330 | /* Search the in-store retry information for the first retry item that applies | |
331 | to a given destination. If the key contains an @ we are probably handling a | |
332 | local delivery and have a complete address to search for; this happens when | |
333 | retry_use_local_part is set on a router. Otherwise, the key is likely to be a | |
334 | host name for a remote delivery, or a domain name for a local delivery. We | |
335 | prepend *@ on the front of it so that it will match a retry item whose address | |
336 | item pattern is independent of the local part. The alternate key, if set, is | |
337 | always just a domain, so we treat it likewise. | |
338 | ||
339 | Arguments: | |
340 | key key for which retry info is wanted | |
341 | alternate alternative key, always just a domain | |
342 | basic_errno specific error predicate on the retry rule, or zero | |
343 | more_errno additional data for errno predicate | |
344 | ||
345 | Returns: pointer to retry rule, or NULL | |
346 | */ | |
347 | ||
348 | retry_config * | |
349 | retry_find_config(uschar *key, uschar *alternate, int basic_errno, | |
350 | int more_errno) | |
351 | { | |
ea49d0e1 | 352 | int replace = 0; |
059ec3d9 PH |
353 | uschar *use_key, *use_alternate; |
354 | uschar *colon = Ustrchr(key, ':'); | |
355 | retry_config *yield; | |
356 | ||
ea49d0e1 PH |
357 | /* If there's a colon in the key, there are two possibilities: |
358 | ||
359 | (1) This is a key for a host, ip address, and possibly port, in the format | |
360 | ||
361 | hostname:ip+port | |
362 | ||
363 | In this case, we temporarily replace the colon with a zero, to terminate | |
364 | the string after the host name. | |
365 | ||
366 | (2) This is a key for a pipe, file, or autoreply delivery, in the format | |
367 | ||
368 | pipe-or-file-or-auto:x@y | |
369 | ||
370 | where x@y is the original address that provoked the delivery. The pipe or | |
371 | file or auto will start with | or / or >, whereas a host name will start | |
372 | with a letter or a digit. In this case we want to use the original address | |
373 | to search for a retry rule. */ | |
059ec3d9 PH |
374 | |
375 | if (colon != NULL) | |
376 | { | |
ea49d0e1 PH |
377 | if (isalnum(*key)) |
378 | replace = ':'; | |
379 | else | |
380 | key = Ustrrchr(key, ':') + 1; /* Take from the last colon */ | |
059ec3d9 | 381 | } |
ea49d0e1 PH |
382 | |
383 | if (replace == 0) colon = key + Ustrlen(key); | |
059ec3d9 PH |
384 | *colon = 0; |
385 | ||
386 | /* Sort out the keys */ | |
387 | ||
388 | use_key = (Ustrchr(key, '@') != NULL)? key : string_sprintf("*@%s", key); | |
389 | use_alternate = (alternate == NULL)? NULL : string_sprintf("*@%s", alternate); | |
390 | ||
391 | /* Scan the configured retry items. */ | |
392 | ||
393 | for (yield = retries; yield != NULL; yield = yield->next) | |
394 | { | |
395 | uschar *plist = yield->pattern; | |
396 | uschar *slist = yield->senders; | |
397 | ||
398 | /* If a specific error is set for this item, check that we are handling that | |
399 | specific error, and if so, check any additional error information if | |
400 | required. */ | |
401 | ||
402 | if (yield->basic_errno != 0) | |
403 | { | |
404 | /* Special code is required for quota errors, as these can either be system | |
405 | quota errors, or Exim's own quota imposition, which has a different error | |
406 | number. Full partitions are also treated in the same way as quota errors. | |
407 | */ | |
408 | ||
409 | if (yield->basic_errno == ERRNO_EXIMQUOTA) | |
410 | { | |
411 | if ((basic_errno != ERRNO_EXIMQUOTA && basic_errno != errno_quota && | |
412 | basic_errno != ENOSPC) || | |
413 | (yield->more_errno != 0 && yield->more_errno > more_errno)) | |
414 | continue; | |
415 | } | |
416 | ||
417 | /* Handle 4xx responses to RCPT. The code that was received is in the 2nd | |
418 | least significant byte of more_errno (with 400 subtracted). The required | |
419 | value is coded in the 2nd least significant byte of the yield->more_errno | |
420 | field as follows: | |
421 | ||
422 | 255 => any 4xx code | |
423 | >= 100 => the decade must match the value less 100 | |
424 | < 100 => the exact value must match | |
425 | */ | |
426 | ||
427 | else if (yield->basic_errno == ERRNO_RCPT4XX) | |
428 | { | |
429 | int wanted; | |
430 | if (basic_errno != ERRNO_RCPT4XX) continue; | |
431 | wanted = (yield->more_errno >> 8) & 255; | |
432 | if (wanted != 255) | |
433 | { | |
434 | int evalue = (more_errno >> 8) & 255; | |
435 | if (wanted >= 100) | |
436 | { | |
437 | if ((evalue/10)*10 != wanted - 100) continue; | |
438 | } | |
439 | else if (evalue != wanted) continue; | |
440 | } | |
441 | } | |
442 | ||
443 | /* There are some special cases for timeouts */ | |
444 | ||
445 | else if (yield->basic_errno == ETIMEDOUT) | |
446 | { | |
447 | if (basic_errno != ETIMEDOUT) continue; | |
448 | ||
449 | /* Just RTEF_CTOUT in the rule => don't care about 'A'/'M' addresses */ | |
450 | if (yield->more_errno == RTEF_CTOUT) | |
451 | { | |
452 | if ((more_errno & RTEF_CTOUT) == 0) continue; | |
453 | } | |
454 | ||
455 | else if (yield->more_errno != 0) | |
456 | { | |
457 | int cf_errno = more_errno; | |
458 | if ((yield->more_errno & RTEF_CTOUT) == 0) cf_errno &= ~RTEF_CTOUT; | |
459 | if (yield->more_errno != cf_errno) continue; | |
460 | } | |
461 | } | |
462 | ||
463 | /* Default checks for exact match */ | |
464 | ||
465 | else | |
466 | { | |
467 | if (yield->basic_errno != basic_errno || | |
468 | (yield->more_errno != 0 && yield->more_errno != more_errno)) | |
469 | continue; | |
470 | } | |
471 | } | |
472 | ||
473 | /* If the "senders" condition is set, check it. Note that sender_address may | |
474 | be null during -brt checking, in which case we do not use this rule. */ | |
475 | ||
476 | if (slist != NULL && (sender_address == NULL || | |
477 | match_address_list(sender_address, TRUE, TRUE, &slist, NULL, -1, 0, | |
478 | NULL) != OK)) | |
479 | continue; | |
480 | ||
481 | /* Check for a match between the address list item at the start of this retry | |
482 | rule and either the main or alternate keys. */ | |
483 | ||
484 | if (match_address_list(use_key, TRUE, TRUE, &plist, NULL, -1, UCHAR_MAX+1, | |
485 | NULL) == OK || | |
486 | (use_alternate != NULL && | |
487 | match_address_list(use_alternate, TRUE, TRUE, &plist, NULL, -1, | |
488 | UCHAR_MAX+1, NULL) == OK)) | |
489 | break; | |
490 | } | |
491 | ||
492 | *colon = replace; | |
493 | return yield; | |
494 | } | |
495 | ||
496 | ||
497 | ||
498 | ||
499 | /************************************************* | |
500 | * Update retry database * | |
501 | *************************************************/ | |
502 | ||
503 | /* Update the retry data for any directing/routing/transporting that was | |
504 | deferred, or delete it for those that succeeded after a previous defer. This is | |
505 | done all in one go to minimize opening/closing/locking of the database file. | |
506 | ||
507 | Note that, because SMTP delivery involves a list of destinations to try, there | |
508 | may be defer-type retry information for some of them even when the message was | |
509 | successfully delivered. Likewise if it eventually failed. | |
510 | ||
511 | This function may move addresses from the defer to the failed queue if the | |
512 | ultimate retry time has expired. | |
513 | ||
514 | Arguments: | |
515 | addr_defer queue of deferred addresses | |
516 | addr_failed queue of failed addresses | |
517 | addr_succeed queue of successful addresses | |
518 | ||
519 | Returns: nothing | |
520 | */ | |
521 | ||
522 | void | |
523 | retry_update(address_item **addr_defer, address_item **addr_failed, | |
524 | address_item **addr_succeed) | |
525 | { | |
526 | open_db dbblock; | |
527 | open_db *dbm_file = NULL; | |
528 | time_t now = time(NULL); | |
529 | int i; | |
530 | ||
531 | DEBUG(D_retry) debug_printf("Processing retry items\n"); | |
532 | ||
533 | /* Three-times loop to handle succeeded, failed, and deferred addresses. | |
534 | Deferred addresses must be handled after failed ones, because some may be moved | |
535 | to the failed chain if they have timed out. */ | |
536 | ||
537 | for (i = 0; i < 3; i++) | |
538 | { | |
539 | address_item *endaddr, *addr; | |
540 | address_item *last_first = NULL; | |
541 | address_item **paddr = (i==0)? addr_succeed : | |
542 | (i==1)? addr_failed : addr_defer; | |
543 | address_item **saved_paddr = NULL; | |
544 | ||
545 | DEBUG(D_retry) debug_printf("%s addresses:\n", (i == 0)? "Succeeded" : | |
546 | (i == 1)? "Failed" : "Deferred"); | |
547 | ||
548 | /* Loop for each address on the chain. For deferred addresses, the whole | |
549 | address times out unless one of its retry addresses has a retry rule that | |
550 | hasn't yet timed out. Deferred addresses should not be requesting deletion | |
551 | of retry items, but just in case they do by accident, treat that case | |
552 | as "not timed out". | |
553 | ||
554 | As well as handling the addresses themselves, we must also process any | |
555 | retry items for any parent addresses - these are typically "delete" items, | |
556 | because the parent must have succeeded in order to generate the child. */ | |
557 | ||
558 | while ((endaddr = *paddr) != NULL) | |
559 | { | |
560 | BOOL timed_out = FALSE; | |
561 | retry_item *rti; | |
562 | ||
563 | for (addr = endaddr; addr != NULL; addr = addr->parent) | |
564 | { | |
565 | int update_count = 0; | |
566 | int timedout_count = 0; | |
567 | ||
568 | DEBUG(D_retry) debug_printf("%s%s\n", addr->address, (addr->retries == NULL)? | |
569 | ": no retry items" : ""); | |
570 | ||
571 | /* Loop for each retry item. */ | |
572 | ||
573 | for (rti = addr->retries; rti != NULL; rti = rti->next) | |
574 | { | |
575 | uschar *message; | |
576 | int message_length, message_space, failing_interval, next_try; | |
577 | retry_rule *rule, *final_rule; | |
578 | retry_config *retry; | |
579 | dbdata_retry *retry_record; | |
580 | ||
581 | /* Open the retry database if it is not already open; failure to open | |
582 | the file is logged, but otherwise ignored - deferred addresses will | |
583 | get retried at the next opportunity. Not opening earlier than this saves | |
584 | opening if no addresses have retry items - common when none have yet | |
585 | reached their retry next try time. */ | |
586 | ||
587 | if (dbm_file == NULL) | |
588 | dbm_file = dbfn_open(US"retry", O_RDWR, &dbblock, TRUE); | |
589 | ||
590 | if (dbm_file == NULL) | |
591 | { | |
592 | DEBUG(D_deliver|D_retry|D_hints_lookup) | |
593 | debug_printf("retry database not available for updating\n"); | |
594 | return; | |
595 | } | |
596 | ||
597 | /* If there are no deferred addresses, that is, if this message is | |
598 | completing, and the retry item is for a message-specific SMTP error, | |
599 | force it to be deleted, because there's no point in keeping data for | |
600 | no-longer-existing messages. This situation can occur when a domain has | |
601 | two hosts and a message-specific error occurs for the first of them, | |
602 | but the address gets delivered to the second one. This optimization | |
603 | doesn't succeed in cleaning out all the dead entries, but it helps. */ | |
604 | ||
605 | if (*addr_defer == NULL && (rti->flags & rf_message) != 0) | |
606 | rti->flags |= rf_delete; | |
607 | ||
608 | /* Handle the case of a request to delete the retry info for this | |
609 | destination. */ | |
610 | ||
611 | if ((rti->flags & rf_delete) != 0) | |
612 | { | |
613 | (void)dbfn_delete(dbm_file, rti->key); | |
614 | DEBUG(D_retry) | |
615 | debug_printf("deleted retry information for %s\n", rti->key); | |
616 | continue; | |
617 | } | |
618 | ||
619 | /* Count the number of non-delete retry items. This is so that we | |
620 | can compare it to the count of timed_out ones, to check whether | |
621 | all are timed out. */ | |
622 | ||
623 | update_count++; | |
624 | ||
625 | /* Get the retry information for this destination and error code, if | |
626 | any. If this item is for a remote host with ip address, then pass | |
627 | the domain name as an alternative to search for. If no retry | |
628 | information is found, we can't generate a retry time, so there is | |
629 | no point updating the database. This retry item is timed out. */ | |
630 | ||
631 | if ((retry = retry_find_config(rti->key + 2, | |
632 | ((rti->flags & rf_host) != 0)? addr->domain : NULL, | |
633 | rti->basic_errno, rti->more_errno)) == NULL) | |
634 | { | |
635 | DEBUG(D_retry) debug_printf("No configured retry item for %s%s%s\n", | |
636 | rti->key, | |
637 | ((rti->flags & rf_host) != 0)? US" or " : US"", | |
638 | ((rti->flags & rf_host) != 0)? addr->domain : US""); | |
639 | if (addr == endaddr) timedout_count++; | |
640 | continue; | |
641 | } | |
642 | ||
643 | DEBUG(D_retry) | |
644 | { | |
645 | if ((rti->flags & rf_host) != 0) | |
ea49d0e1 PH |
646 | debug_printf("retry for %s (%s) = %s %d %d\n", rti->key, |
647 | addr->domain, retry->pattern, retry->basic_errno, | |
648 | retry->more_errno); | |
059ec3d9 | 649 | else |
ea49d0e1 PH |
650 | debug_printf("retry for %s = %s %d %d\n", rti->key, retry->pattern, |
651 | retry->basic_errno, retry->more_errno); | |
059ec3d9 PH |
652 | } |
653 | ||
654 | /* Set up the message for the database retry record. Because DBM | |
655 | records have a maximum data length, we enforce a limit. There isn't | |
656 | much point in keeping a huge message here, anyway. */ | |
657 | ||
658 | message = (rti->basic_errno > 0)? US strerror(rti->basic_errno) : | |
659 | (rti->message == NULL)? | |
660 | US"unknown error" : string_printing(rti->message); | |
661 | message_length = Ustrlen(message); | |
662 | if (message_length > 150) message_length = 150; | |
663 | ||
664 | /* Read a retry record from the database or construct a new one. | |
665 | Ignore an old one if it is too old since it was last updated. */ | |
666 | ||
667 | retry_record = dbfn_read(dbm_file, rti->key); | |
668 | if (retry_record != NULL && | |
669 | now - retry_record->time_stamp > retry_data_expire) | |
670 | retry_record = NULL; | |
671 | ||
672 | if (retry_record == NULL) | |
673 | { | |
674 | retry_record = store_get(sizeof(dbdata_retry) + message_length); | |
675 | message_space = message_length; | |
676 | retry_record->first_failed = now; | |
677 | retry_record->last_try = now; | |
678 | retry_record->next_try = now; | |
679 | retry_record->expired = FALSE; | |
680 | retry_record->text[0] = 0; /* just in case */ | |
681 | } | |
682 | else message_space = Ustrlen(retry_record->text); | |
683 | ||
684 | /* Compute how long this destination has been failing */ | |
685 | ||
686 | failing_interval = now - retry_record->first_failed; | |
687 | ||
688 | /* Search for the current retry rule. The cutoff time of the | |
689 | last rule is handled differently to the others. The rule continues | |
690 | to operate for ever (the global maximum interval will eventually | |
691 | limit the gaps) but its cutoff time determines when an individual | |
692 | destination times out. If there are no retry rules, the destination | |
693 | always times out, but we can't compute a retry time. */ | |
694 | ||
695 | final_rule = NULL; | |
696 | for (rule = retry->rules; rule != NULL; rule = rule->next) | |
697 | { | |
698 | if (failing_interval <= rule->timeout) break; | |
699 | final_rule = rule; | |
700 | } | |
701 | ||
702 | /* If there's an un-timed out rule, the destination has not | |
703 | yet timed out, so the address as a whole has not timed out (but we are | |
704 | interested in this only for the end address). Make sure the expired | |
705 | flag is false (can be forced via fixdb from outside, but ensure it is | |
706 | consistent with the rules whenever we go through here). */ | |
707 | ||
708 | if (rule != NULL) | |
709 | { | |
710 | retry_record->expired = FALSE; | |
711 | } | |
712 | ||
713 | /* Otherwise, set the retry timeout expired, and set the final rule | |
714 | as the one from which to compute the next retry time. Subsequent | |
715 | messages will fail immediately until the retry time is reached (unless | |
716 | there are other, still active, retries). */ | |
717 | ||
718 | else | |
719 | { | |
720 | rule = final_rule; | |
721 | retry_record->expired = TRUE; | |
722 | if (addr == endaddr) timedout_count++; | |
723 | } | |
724 | ||
725 | /* There is a special case to consider when some messages get through | |
726 | to a destination and others don't. This can happen locally when a | |
727 | large message pushes a user over quota, and it can happen remotely | |
728 | when a machine is on a dodgy Internet connection. The messages that | |
729 | get through wipe the retry information, causing those that don't to | |
730 | stay on the queue longer than the final retry time. In order to | |
731 | avoid this, we check, using the time of arrival of the message, to | |
732 | see if it has been on the queue for more than the final cutoff time, | |
733 | and if so, cause this retry item to time out, and the retry time to | |
734 | be set to "now" so that any subsequent messages in the same condition | |
735 | also get tried. We search for the last rule onwards from the one that | |
736 | is in use. If there are no retry rules for the item, rule will be null | |
737 | and timedout_count will already have been updated. | |
738 | ||
739 | This implements "timeout this rule if EITHER the host (or routing or | |
740 | directing) has been failing for more than the maximum time, OR if the | |
741 | message has been on the queue for more than the maximum time." */ | |
742 | ||
743 | if (received_time <= retry_record->first_failed && | |
744 | addr == endaddr && !retry_record->expired && rule != NULL) | |
745 | { | |
746 | retry_rule *last_rule; | |
747 | for (last_rule = rule; | |
748 | last_rule->next != NULL; | |
749 | last_rule = last_rule->next); | |
750 | if (now - received_time > last_rule->timeout) | |
751 | { | |
752 | DEBUG(D_retry) debug_printf("on queue longer than maximum retry\n"); | |
753 | timedout_count++; | |
754 | rule = NULL; | |
755 | } | |
756 | } | |
757 | ||
758 | /* Compute the next try time from the rule, subject to the global | |
759 | maximum, and update the retry database. If rule == NULL it means | |
760 | there were no rules at all (and the timeout will be set expired), | |
761 | or we have a message that is older than the final timeout. In this | |
762 | case set the next retry time to now, so that one delivery attempt | |
763 | happens for subsequent messages. */ | |
764 | ||
765 | if (rule == NULL) next_try = now; else | |
766 | { | |
767 | if (rule->rule == 'F') next_try = now + rule->p1; | |
6af56900 | 768 | else /* rule = 'G' or 'H' */ |
059ec3d9 PH |
769 | { |
770 | int last_predicted_gap = | |
771 | retry_record->next_try - retry_record->last_try; | |
772 | int last_actual_gap = now - retry_record->last_try; | |
773 | int lastgap = (last_predicted_gap < last_actual_gap)? | |
774 | last_predicted_gap : last_actual_gap; | |
6af56900 PH |
775 | int next_gap = (lastgap * rule->p2)/1000; |
776 | if (rule->rule == 'G') | |
777 | { | |
778 | next_try = now + ((lastgap < rule->p1)? rule->p1 : next_gap); | |
779 | } | |
780 | else /* The 'H' rule */ | |
781 | { | |
782 | next_try = now + rule->p1; | |
783 | if (next_gap > rule->p1) | |
784 | next_try += random_number(next_gap - rule->p1); | |
785 | } | |
059ec3d9 PH |
786 | } |
787 | } | |
788 | ||
789 | /* Impose a global retry max */ | |
790 | ||
791 | if (next_try - now > retry_interval_max) | |
792 | next_try = now + retry_interval_max; | |
793 | ||
794 | /* If the new message length is greater than the previous one, we | |
795 | have to copy the record first. */ | |
796 | ||
797 | if (message_length > message_space) | |
798 | { | |
799 | dbdata_retry *newr = store_get(sizeof(dbdata_retry) + message_length); | |
800 | memcpy(newr, retry_record, sizeof(dbdata_retry)); | |
801 | retry_record = newr; | |
802 | } | |
803 | ||
804 | /* Set up the retry record; message_length may be less than the string | |
805 | length for very long error strings. */ | |
806 | ||
807 | retry_record->last_try = now; | |
808 | retry_record->next_try = next_try; | |
809 | retry_record->basic_errno = rti->basic_errno; | |
810 | retry_record->more_errno = rti->more_errno; | |
811 | Ustrncpy(retry_record->text, message, message_length); | |
812 | retry_record->text[message_length] = 0; | |
813 | ||
814 | DEBUG(D_retry) | |
815 | { | |
816 | int letter = retry_record->more_errno & 255; | |
817 | debug_printf("Writing retry data for %s\n", rti->key); | |
818 | debug_printf(" first failed=%d last try=%d next try=%d expired=%d\n", | |
819 | (int)retry_record->first_failed, (int)retry_record->last_try, | |
820 | (int)retry_record->next_try, retry_record->expired); | |
821 | debug_printf(" errno=%d more_errno=", retry_record->basic_errno); | |
822 | if (letter == 'A' || letter == 'M') | |
823 | debug_printf("%d,%c", (retry_record->more_errno >> 8) & 255, | |
824 | letter); | |
825 | else | |
826 | debug_printf("%d", retry_record->more_errno); | |
827 | debug_printf(" %s\n", retry_record->text); | |
828 | } | |
829 | ||
830 | (void)dbfn_write(dbm_file, rti->key, retry_record, | |
831 | sizeof(dbdata_retry) + message_length); | |
832 | } /* Loop for each retry item */ | |
833 | ||
834 | /* If all the non-delete retry items are timed out, the address is | |
835 | timed out, provided that we didn't skip any hosts because their retry | |
836 | time was not reached (or because of hosts_max_try). */ | |
837 | ||
838 | if (update_count > 0 && update_count == timedout_count) | |
839 | { | |
840 | if (!testflag(endaddr, af_retry_skipped)) | |
841 | { | |
842 | DEBUG(D_retry) debug_printf("timed out: all retries expired\n"); | |
843 | timed_out = TRUE; | |
844 | } | |
845 | else | |
846 | { | |
847 | DEBUG(D_retry) | |
848 | debug_printf("timed out but some hosts were skipped\n"); | |
849 | } | |
850 | } | |
851 | } /* Loop for an address and its parents */ | |
852 | ||
853 | /* If this is a deferred address, and retry processing was requested by | |
854 | means of one or more retry items, and they all timed out, move the address | |
855 | to the failed queue, and restart this loop without updating paddr. | |
856 | ||
857 | If there were several addresses batched in the same remote delivery, only | |
858 | the original top one will have host retry items attached to it, but we want | |
859 | to handle all the same. Each will have a pointer back to its "top" address, | |
860 | and they will now precede the item with the retries because addresses are | |
861 | inverted when added to these final queues. We have saved information about | |
862 | them in passing (below) so they can all be cut out at once. */ | |
863 | ||
864 | if (i == 2) /* Handling defers */ | |
865 | { | |
866 | if (endaddr->retries != NULL && timed_out) | |
867 | { | |
868 | if (last_first == endaddr) paddr = saved_paddr; | |
869 | addr = *paddr; | |
870 | *paddr = endaddr->next; | |
871 | ||
872 | endaddr->next = *addr_failed; | |
873 | *addr_failed = addr; | |
874 | ||
875 | for (;; addr = addr->next) | |
876 | { | |
877 | setflag(addr, af_retry_timedout); | |
878 | addr->message = (addr->message == NULL)? US"retry timeout exceeded" : | |
879 | string_sprintf("%s: retry timeout exceeded", addr->message); | |
fffffe4c PH |
880 | addr->user_message = (addr->user_message == NULL)? |
881 | US"retry timeout exceeded" : | |
882 | string_sprintf("%s: retry timeout exceeded", addr->user_message); | |
059ec3d9 PH |
883 | log_write(0, LOG_MAIN, "** %s%s%s%s: retry timeout exceeded", |
884 | addr->address, | |
885 | (addr->parent == NULL)? US"" : US" <", | |
886 | (addr->parent == NULL)? US"" : addr->parent->address, | |
887 | (addr->parent == NULL)? US"" : US">"); | |
888 | ||
889 | if (addr == endaddr) break; | |
890 | } | |
891 | ||
892 | continue; /* Restart from changed *paddr */ | |
893 | } | |
894 | ||
895 | /* This address is to remain on the defer chain. If it has a "first" | |
896 | pointer, save the pointer to it in case we want to fail the set of | |
897 | addresses when we get to the first one. */ | |
898 | ||
899 | if (endaddr->first != last_first) | |
900 | { | |
901 | last_first = endaddr->first; | |
902 | saved_paddr = paddr; | |
903 | } | |
904 | } | |
905 | ||
906 | /* All cases (succeed, fail, defer left on queue) */ | |
907 | ||
908 | paddr = &(endaddr->next); /* Advance to next address */ | |
909 | } /* Loop for all addresses */ | |
910 | } /* Loop for succeed, fail, defer */ | |
911 | ||
912 | /* Close and unlock the database */ | |
913 | ||
914 | if (dbm_file != NULL) dbfn_close(dbm_file); | |
915 | ||
916 | DEBUG(D_retry) debug_printf("end of retry processing\n"); | |
917 | } | |
918 | ||
919 | /* End of retry.c */ |