Commit | Line | Data |
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420a0d19 CE |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
5 | /* Copyright (c) University of Cambridge 1995 - 2014 */ | |
6 | /* See the file NOTICE for conditions of use and distribution. */ | |
7 | ||
8 | /* Functions concerned with verifying things. The original code for callout | |
9 | caching was contributed by Kevin Fleming (but I hacked it around a bit). */ | |
10 | ||
11 | ||
12 | #include "exim.h" | |
13 | #include "transports/smtp.h" | |
14 | ||
15 | #define CUTTHROUGH_CMD_TIMEOUT 30 /* timeout for cutthrough-routing calls */ | |
16 | #define CUTTHROUGH_DATA_TIMEOUT 60 /* timeout for cutthrough-routing calls */ | |
17 | address_item cutthrough_addr; | |
18 | static smtp_outblock ctblock; | |
19 | uschar ctbuffer[8192]; | |
20 | ||
21 | ||
22 | /* Structure for caching DNSBL lookups */ | |
23 | ||
24 | typedef struct dnsbl_cache_block { | |
25 | dns_address *rhs; | |
26 | uschar *text; | |
27 | int rc; | |
28 | BOOL text_set; | |
29 | } dnsbl_cache_block; | |
30 | ||
31 | ||
32 | /* Anchor for DNSBL cache */ | |
33 | ||
34 | static tree_node *dnsbl_cache = NULL; | |
35 | ||
36 | ||
37 | /* Bits for match_type in one_check_dnsbl() */ | |
38 | ||
39 | #define MT_NOT 1 | |
40 | #define MT_ALL 2 | |
41 | ||
42 | ||
43 | ||
44 | /************************************************* | |
45 | * Retrieve a callout cache record * | |
46 | *************************************************/ | |
47 | ||
48 | /* If a record exists, check whether it has expired. | |
49 | ||
50 | Arguments: | |
51 | dbm_file an open hints file | |
52 | key the record key | |
53 | type "address" or "domain" | |
54 | positive_expire expire time for positive records | |
55 | negative_expire expire time for negative records | |
56 | ||
57 | Returns: the cache record if a non-expired one exists, else NULL | |
58 | */ | |
59 | ||
60 | static dbdata_callout_cache * | |
61 | get_callout_cache_record(open_db *dbm_file, uschar *key, uschar *type, | |
62 | int positive_expire, int negative_expire) | |
63 | { | |
64 | BOOL negative; | |
65 | int length, expire; | |
66 | time_t now; | |
67 | dbdata_callout_cache *cache_record; | |
68 | ||
69 | cache_record = dbfn_read_with_length(dbm_file, key, &length); | |
70 | ||
71 | if (cache_record == NULL) | |
72 | { | |
73 | HDEBUG(D_verify) debug_printf("callout cache: no %s record found\n", type); | |
74 | return NULL; | |
75 | } | |
76 | ||
77 | /* We treat a record as "negative" if its result field is not positive, or if | |
78 | it is a domain record and the postmaster field is negative. */ | |
79 | ||
80 | negative = cache_record->result != ccache_accept || | |
81 | (type[0] == 'd' && cache_record->postmaster_result == ccache_reject); | |
82 | expire = negative? negative_expire : positive_expire; | |
83 | now = time(NULL); | |
84 | ||
85 | if (now - cache_record->time_stamp > expire) | |
86 | { | |
87 | HDEBUG(D_verify) debug_printf("callout cache: %s record expired\n", type); | |
88 | return NULL; | |
89 | } | |
90 | ||
91 | /* If this is a non-reject domain record, check for the obsolete format version | |
92 | that doesn't have the postmaster and random timestamps, by looking at the | |
93 | length. If so, copy it to a new-style block, replicating the record's | |
94 | timestamp. Then check the additional timestamps. (There's no point wasting | |
95 | effort if connections are rejected.) */ | |
96 | ||
97 | if (type[0] == 'd' && cache_record->result != ccache_reject) | |
98 | { | |
99 | if (length == sizeof(dbdata_callout_cache_obs)) | |
100 | { | |
101 | dbdata_callout_cache *new = store_get(sizeof(dbdata_callout_cache)); | |
102 | memcpy(new, cache_record, length); | |
103 | new->postmaster_stamp = new->random_stamp = new->time_stamp; | |
104 | cache_record = new; | |
105 | } | |
106 | ||
107 | if (now - cache_record->postmaster_stamp > expire) | |
108 | cache_record->postmaster_result = ccache_unknown; | |
109 | ||
110 | if (now - cache_record->random_stamp > expire) | |
111 | cache_record->random_result = ccache_unknown; | |
112 | } | |
113 | ||
114 | HDEBUG(D_verify) debug_printf("callout cache: found %s record\n", type); | |
115 | return cache_record; | |
116 | } | |
117 | ||
118 | ||
119 | ||
120 | /************************************************* | |
121 | * Do callout verification for an address * | |
122 | *************************************************/ | |
123 | ||
124 | /* This function is called from verify_address() when the address has routed to | |
125 | a host list, and a callout has been requested. Callouts are expensive; that is | |
126 | why a cache is used to improve the efficiency. | |
127 | ||
128 | Arguments: | |
129 | addr the address that's been routed | |
130 | host_list the list of hosts to try | |
131 | tf the transport feedback block | |
132 | ||
133 | ifstring "interface" option from transport, or NULL | |
134 | portstring "port" option from transport, or NULL | |
135 | protocolstring "protocol" option from transport, or NULL | |
136 | callout the per-command callout timeout | |
137 | callout_overall the overall callout timeout (if < 0 use 4*callout) | |
138 | callout_connect the callout connection timeout (if < 0 use callout) | |
139 | options the verification options - these bits are used: | |
140 | vopt_is_recipient => this is a recipient address | |
141 | vopt_callout_no_cache => don't use callout cache | |
142 | vopt_callout_fullpm => if postmaster check, do full one | |
143 | vopt_callout_random => do the "random" thing | |
144 | vopt_callout_recipsender => use real sender for recipient | |
145 | vopt_callout_recippmaster => use postmaster for recipient | |
146 | se_mailfrom MAIL FROM address for sender verify; NULL => "" | |
147 | pm_mailfrom if non-NULL, do the postmaster check with this sender | |
148 | ||
149 | Returns: OK/FAIL/DEFER | |
150 | */ | |
151 | ||
152 | static int | |
153 | do_callout(address_item *addr, host_item *host_list, transport_feedback *tf, | |
154 | int callout, int callout_overall, int callout_connect, int options, | |
155 | uschar *se_mailfrom, uschar *pm_mailfrom) | |
156 | { | |
157 | BOOL is_recipient = (options & vopt_is_recipient) != 0; | |
158 | BOOL callout_no_cache = (options & vopt_callout_no_cache) != 0; | |
159 | BOOL callout_random = (options & vopt_callout_random) != 0; | |
160 | ||
161 | int yield = OK; | |
162 | int old_domain_cache_result = ccache_accept; | |
163 | BOOL done = FALSE; | |
164 | uschar *address_key; | |
165 | uschar *from_address; | |
166 | uschar *random_local_part = NULL; | |
167 | uschar *save_deliver_domain = deliver_domain; | |
168 | uschar **failure_ptr = is_recipient? | |
169 | &recipient_verify_failure : &sender_verify_failure; | |
170 | open_db dbblock; | |
171 | open_db *dbm_file = NULL; | |
172 | dbdata_callout_cache new_domain_record; | |
173 | dbdata_callout_cache_address new_address_record; | |
174 | host_item *host; | |
175 | time_t callout_start_time; | |
176 | ||
177 | new_domain_record.result = ccache_unknown; | |
178 | new_domain_record.postmaster_result = ccache_unknown; | |
179 | new_domain_record.random_result = ccache_unknown; | |
180 | ||
181 | memset(&new_address_record, 0, sizeof(new_address_record)); | |
182 | ||
183 | /* For a recipient callout, the key used for the address cache record must | |
184 | include the sender address if we are using the real sender in the callout, | |
185 | because that may influence the result of the callout. */ | |
186 | ||
187 | address_key = addr->address; | |
188 | from_address = US""; | |
189 | ||
190 | if (is_recipient) | |
191 | { | |
192 | if ((options & vopt_callout_recipsender) != 0) | |
193 | { | |
194 | address_key = string_sprintf("%s/<%s>", addr->address, sender_address); | |
195 | from_address = sender_address; | |
196 | } | |
197 | else if ((options & vopt_callout_recippmaster) != 0) | |
198 | { | |
199 | address_key = string_sprintf("%s/<postmaster@%s>", addr->address, | |
200 | qualify_domain_sender); | |
201 | from_address = string_sprintf("postmaster@%s", qualify_domain_sender); | |
202 | } | |
203 | } | |
204 | ||
205 | /* For a sender callout, we must adjust the key if the mailfrom address is not | |
206 | empty. */ | |
207 | ||
208 | else | |
209 | { | |
210 | from_address = (se_mailfrom == NULL)? US"" : se_mailfrom; | |
211 | if (from_address[0] != 0) | |
212 | address_key = string_sprintf("%s/<%s>", addr->address, from_address); | |
213 | } | |
214 | ||
215 | /* Open the callout cache database, it it exists, for reading only at this | |
216 | stage, unless caching has been disabled. */ | |
217 | ||
218 | if (callout_no_cache) | |
219 | { | |
220 | HDEBUG(D_verify) debug_printf("callout cache: disabled by no_cache\n"); | |
221 | } | |
222 | else if ((dbm_file = dbfn_open(US"callout", O_RDWR, &dbblock, FALSE)) == NULL) | |
223 | { | |
224 | HDEBUG(D_verify) debug_printf("callout cache: not available\n"); | |
225 | } | |
226 | ||
227 | /* If a cache database is available see if we can avoid the need to do an | |
228 | actual callout by making use of previously-obtained data. */ | |
229 | ||
230 | if (dbm_file != NULL) | |
231 | { | |
232 | dbdata_callout_cache_address *cache_address_record; | |
233 | dbdata_callout_cache *cache_record = get_callout_cache_record(dbm_file, | |
234 | addr->domain, US"domain", | |
235 | callout_cache_domain_positive_expire, | |
236 | callout_cache_domain_negative_expire); | |
237 | ||
238 | /* If an unexpired cache record was found for this domain, see if the callout | |
239 | process can be short-circuited. */ | |
240 | ||
241 | if (cache_record != NULL) | |
242 | { | |
243 | /* In most cases, if an early command (up to and including MAIL FROM:<>) | |
244 | was rejected, there is no point carrying on. The callout fails. However, if | |
245 | we are doing a recipient verification with use_sender or use_postmaster | |
246 | set, a previous failure of MAIL FROM:<> doesn't count, because this time we | |
247 | will be using a non-empty sender. We have to remember this situation so as | |
248 | not to disturb the cached domain value if this whole verification succeeds | |
249 | (we don't want it turning into "accept"). */ | |
250 | ||
251 | old_domain_cache_result = cache_record->result; | |
252 | ||
253 | if (cache_record->result == ccache_reject || | |
254 | (*from_address == 0 && cache_record->result == ccache_reject_mfnull)) | |
255 | { | |
256 | setflag(addr, af_verify_nsfail); | |
257 | HDEBUG(D_verify) | |
258 | debug_printf("callout cache: domain gave initial rejection, or " | |
259 | "does not accept HELO or MAIL FROM:<>\n"); | |
260 | setflag(addr, af_verify_nsfail); | |
261 | addr->user_message = US"(result of an earlier callout reused)."; | |
262 | yield = FAIL; | |
263 | *failure_ptr = US"mail"; | |
264 | goto END_CALLOUT; | |
265 | } | |
266 | ||
267 | /* If a previous check on a "random" local part was accepted, we assume | |
268 | that the server does not do any checking on local parts. There is therefore | |
269 | no point in doing the callout, because it will always be successful. If a | |
270 | random check previously failed, arrange not to do it again, but preserve | |
271 | the data in the new record. If a random check is required but hasn't been | |
272 | done, skip the remaining cache processing. */ | |
273 | ||
274 | if (callout_random) switch(cache_record->random_result) | |
275 | { | |
276 | case ccache_accept: | |
277 | HDEBUG(D_verify) | |
278 | debug_printf("callout cache: domain accepts random addresses\n"); | |
279 | goto END_CALLOUT; /* Default yield is OK */ | |
280 | ||
281 | case ccache_reject: | |
282 | HDEBUG(D_verify) | |
283 | debug_printf("callout cache: domain rejects random addresses\n"); | |
284 | callout_random = FALSE; | |
285 | new_domain_record.random_result = ccache_reject; | |
286 | new_domain_record.random_stamp = cache_record->random_stamp; | |
287 | break; | |
288 | ||
289 | default: | |
290 | HDEBUG(D_verify) | |
291 | debug_printf("callout cache: need to check random address handling " | |
292 | "(not cached or cache expired)\n"); | |
293 | goto END_CACHE; | |
294 | } | |
295 | ||
296 | /* If a postmaster check is requested, but there was a previous failure, | |
297 | there is again no point in carrying on. If a postmaster check is required, | |
298 | but has not been done before, we are going to have to do a callout, so skip | |
299 | remaining cache processing. */ | |
300 | ||
301 | if (pm_mailfrom != NULL) | |
302 | { | |
303 | if (cache_record->postmaster_result == ccache_reject) | |
304 | { | |
305 | setflag(addr, af_verify_pmfail); | |
306 | HDEBUG(D_verify) | |
307 | debug_printf("callout cache: domain does not accept " | |
308 | "RCPT TO:<postmaster@domain>\n"); | |
309 | yield = FAIL; | |
310 | *failure_ptr = US"postmaster"; | |
311 | setflag(addr, af_verify_pmfail); | |
312 | addr->user_message = US"(result of earlier verification reused)."; | |
313 | goto END_CALLOUT; | |
314 | } | |
315 | if (cache_record->postmaster_result == ccache_unknown) | |
316 | { | |
317 | HDEBUG(D_verify) | |
318 | debug_printf("callout cache: need to check RCPT " | |
319 | "TO:<postmaster@domain> (not cached or cache expired)\n"); | |
320 | goto END_CACHE; | |
321 | } | |
322 | ||
323 | /* If cache says OK, set pm_mailfrom NULL to prevent a redundant | |
324 | postmaster check if the address itself has to be checked. Also ensure | |
325 | that the value in the cache record is preserved (with its old timestamp). | |
326 | */ | |
327 | ||
328 | HDEBUG(D_verify) debug_printf("callout cache: domain accepts RCPT " | |
329 | "TO:<postmaster@domain>\n"); | |
330 | pm_mailfrom = NULL; | |
331 | new_domain_record.postmaster_result = ccache_accept; | |
332 | new_domain_record.postmaster_stamp = cache_record->postmaster_stamp; | |
333 | } | |
334 | } | |
335 | ||
336 | /* We can't give a result based on information about the domain. See if there | |
337 | is an unexpired cache record for this specific address (combined with the | |
338 | sender address if we are doing a recipient callout with a non-empty sender). | |
339 | */ | |
340 | ||
341 | cache_address_record = (dbdata_callout_cache_address *) | |
342 | get_callout_cache_record(dbm_file, | |
343 | address_key, US"address", | |
344 | callout_cache_positive_expire, | |
345 | callout_cache_negative_expire); | |
346 | ||
347 | if (cache_address_record != NULL) | |
348 | { | |
349 | if (cache_address_record->result == ccache_accept) | |
350 | { | |
351 | HDEBUG(D_verify) | |
352 | debug_printf("callout cache: address record is positive\n"); | |
353 | } | |
354 | else | |
355 | { | |
356 | HDEBUG(D_verify) | |
357 | debug_printf("callout cache: address record is negative\n"); | |
358 | addr->user_message = US"Previous (cached) callout verification failure"; | |
359 | *failure_ptr = US"recipient"; | |
360 | yield = FAIL; | |
361 | } | |
362 | goto END_CALLOUT; | |
363 | } | |
364 | ||
365 | /* Close the cache database while we actually do the callout for real. */ | |
366 | ||
367 | END_CACHE: | |
368 | dbfn_close(dbm_file); | |
369 | dbm_file = NULL; | |
370 | } | |
371 | ||
372 | if (!addr->transport) | |
373 | { | |
374 | HDEBUG(D_verify) debug_printf("cannot callout via null transport\n"); | |
375 | } | |
376 | else if (Ustrcmp(addr->transport->driver_name, "smtp") != 0) | |
377 | log_write(0, LOG_MAIN|LOG_PANIC|LOG_CONFIG_FOR, "callout transport '%s': %s is non-smtp", | |
378 | addr->transport->name, addr->transport->driver_name); | |
379 | else | |
380 | { | |
381 | smtp_transport_options_block *ob = | |
382 | (smtp_transport_options_block *)addr->transport->options_block; | |
383 | ||
384 | /* The information wasn't available in the cache, so we have to do a real | |
385 | callout and save the result in the cache for next time, unless no_cache is set, | |
386 | or unless we have a previously cached negative random result. If we are to test | |
387 | with a random local part, ensure that such a local part is available. If not, | |
388 | log the fact, but carry on without randomming. */ | |
389 | ||
390 | if (callout_random && callout_random_local_part != NULL) | |
391 | { | |
392 | random_local_part = expand_string(callout_random_local_part); | |
393 | if (random_local_part == NULL) | |
394 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand " | |
395 | "callout_random_local_part: %s", expand_string_message); | |
396 | } | |
397 | ||
398 | /* Default the connect and overall callout timeouts if not set, and record the | |
399 | time we are starting so that we can enforce it. */ | |
400 | ||
401 | if (callout_overall < 0) callout_overall = 4 * callout; | |
402 | if (callout_connect < 0) callout_connect = callout; | |
403 | callout_start_time = time(NULL); | |
404 | ||
405 | /* Before doing a real callout, if this is an SMTP connection, flush the SMTP | |
406 | output because a callout might take some time. When PIPELINING is active and | |
407 | there are many recipients, the total time for doing lots of callouts can add up | |
408 | and cause the client to time out. So in this case we forgo the PIPELINING | |
409 | optimization. */ | |
410 | ||
411 | if (smtp_out != NULL && !disable_callout_flush) mac_smtp_fflush(); | |
412 | ||
413 | /* Now make connections to the hosts and do real callouts. The list of hosts | |
414 | is passed in as an argument. */ | |
415 | ||
416 | for (host = host_list; host != NULL && !done; host = host->next) | |
417 | { | |
418 | smtp_inblock inblock; | |
419 | smtp_outblock outblock; | |
420 | int host_af; | |
421 | int port = 25; | |
422 | BOOL send_quit = TRUE; | |
423 | uschar *active_hostname = smtp_active_hostname; | |
424 | BOOL lmtp; | |
425 | BOOL smtps; | |
426 | BOOL esmtp; | |
427 | BOOL suppress_tls = FALSE; | |
428 | uschar *interface = NULL; /* Outgoing interface to use; NULL => any */ | |
429 | uschar inbuffer[4096]; | |
430 | uschar outbuffer[1024]; | |
431 | uschar responsebuffer[4096]; | |
432 | ||
433 | clearflag(addr, af_verify_pmfail); /* postmaster callout flag */ | |
434 | clearflag(addr, af_verify_nsfail); /* null sender callout flag */ | |
435 | ||
436 | /* Skip this host if we don't have an IP address for it. */ | |
437 | ||
438 | if (host->address == NULL) | |
439 | { | |
440 | DEBUG(D_verify) debug_printf("no IP address for host name %s: skipping\n", | |
441 | host->name); | |
442 | continue; | |
443 | } | |
444 | ||
445 | /* Check the overall callout timeout */ | |
446 | ||
447 | if (time(NULL) - callout_start_time >= callout_overall) | |
448 | { | |
449 | HDEBUG(D_verify) debug_printf("overall timeout for callout exceeded\n"); | |
450 | break; | |
451 | } | |
452 | ||
453 | /* Set IPv4 or IPv6 */ | |
454 | ||
455 | host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6; | |
456 | ||
457 | /* Expand and interpret the interface and port strings. The latter will not | |
458 | be used if there is a host-specific port (e.g. from a manualroute router). | |
459 | This has to be delayed till now, because they may expand differently for | |
460 | different hosts. If there's a failure, log it, but carry on with the | |
461 | defaults. */ | |
462 | ||
463 | deliver_host = host->name; | |
464 | deliver_host_address = host->address; | |
465 | deliver_domain = addr->domain; | |
466 | ||
467 | if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface, | |
468 | US"callout") || | |
469 | !smtp_get_port(tf->port, addr, &port, US"callout")) | |
470 | log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address, | |
471 | addr->message); | |
472 | ||
473 | /* Set HELO string according to the protocol */ | |
474 | lmtp= Ustrcmp(tf->protocol, "lmtp") == 0; | |
475 | smtps= Ustrcmp(tf->protocol, "smtps") == 0; | |
476 | ||
477 | ||
478 | HDEBUG(D_verify) debug_printf("interface=%s port=%d\n", interface, port); | |
479 | ||
480 | /* Set up the buffer for reading SMTP response packets. */ | |
481 | ||
482 | inblock.buffer = inbuffer; | |
483 | inblock.buffersize = sizeof(inbuffer); | |
484 | inblock.ptr = inbuffer; | |
485 | inblock.ptrend = inbuffer; | |
486 | ||
487 | /* Set up the buffer for holding SMTP commands while pipelining */ | |
488 | ||
489 | outblock.buffer = outbuffer; | |
490 | outblock.buffersize = sizeof(outbuffer); | |
491 | outblock.ptr = outbuffer; | |
492 | outblock.cmd_count = 0; | |
493 | outblock.authenticating = FALSE; | |
494 | ||
495 | /* Reset the parameters of a TLS session */ | |
496 | tls_out.cipher = tls_out.peerdn = NULL; | |
497 | ||
498 | /* Connect to the host; on failure, just loop for the next one, but we | |
499 | set the error for the last one. Use the callout_connect timeout. */ | |
500 | ||
501 | tls_retry_connection: | |
502 | ||
503 | inblock.sock = outblock.sock = | |
504 | smtp_connect(host, host_af, port, interface, callout_connect, TRUE, NULL); | |
505 | /* reconsider DSCP here */ | |
506 | if (inblock.sock < 0) | |
507 | { | |
508 | addr->message = string_sprintf("could not connect to %s [%s]: %s", | |
509 | host->name, host->address, strerror(errno)); | |
510 | deliver_host = deliver_host_address = NULL; | |
511 | deliver_domain = save_deliver_domain; | |
512 | continue; | |
513 | } | |
514 | ||
515 | /* Expand the helo_data string to find the host name to use. */ | |
516 | ||
517 | if (tf->helo_data != NULL) | |
518 | { | |
519 | uschar *s = expand_string(tf->helo_data); | |
520 | if (s == NULL) | |
521 | log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: failed to expand transport's " | |
522 | "helo_data value for callout: %s", addr->address, | |
523 | expand_string_message); | |
524 | else active_hostname = s; | |
525 | } | |
526 | ||
527 | /* Wait for initial response, and send HELO. The smtp_write_command() | |
528 | function leaves its command in big_buffer. This is used in error responses. | |
529 | Initialize it in case the connection is rejected. */ | |
530 | ||
531 | Ustrcpy(big_buffer, "initial connection"); | |
532 | ||
533 | /* Unless ssl-on-connect, wait for the initial greeting */ | |
534 | smtps_redo_greeting: | |
535 | ||
536 | #ifdef SUPPORT_TLS | |
537 | if (!smtps || (smtps && tls_out.active >= 0)) | |
538 | #endif | |
539 | if (!(done= smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout))) | |
540 | goto RESPONSE_FAILED; | |
541 | ||
542 | /* Not worth checking greeting line for ESMTP support */ | |
543 | if (!(esmtp = verify_check_this_host(&(ob->hosts_avoid_esmtp), NULL, | |
544 | host->name, host->address, NULL) != OK)) | |
545 | DEBUG(D_transport) | |
546 | debug_printf("not sending EHLO (host matches hosts_avoid_esmtp)\n"); | |
547 | ||
548 | tls_redo_helo: | |
549 | ||
550 | #ifdef SUPPORT_TLS | |
551 | if (smtps && tls_out.active < 0) /* ssl-on-connect, first pass */ | |
552 | { | |
553 | tls_offered = TRUE; | |
554 | ob->tls_tempfail_tryclear = FALSE; | |
555 | } | |
556 | else /* all other cases */ | |
557 | #endif | |
558 | ||
559 | { esmtp_retry: | |
560 | ||
561 | if (!(done= smtp_write_command(&outblock, FALSE, "%s %s\r\n", | |
562 | !esmtp? "HELO" : lmtp? "LHLO" : "EHLO", active_hostname) >= 0)) | |
563 | goto SEND_FAILED; | |
564 | if (!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), '2', callout)) | |
565 | { | |
566 | if (errno != 0 || responsebuffer[0] == 0 || lmtp || !esmtp || tls_out.active >= 0) | |
567 | { | |
568 | done= FALSE; | |
569 | goto RESPONSE_FAILED; | |
570 | } | |
571 | #ifdef SUPPORT_TLS | |
572 | tls_offered = FALSE; | |
573 | #endif | |
574 | esmtp = FALSE; | |
575 | goto esmtp_retry; /* fallback to HELO */ | |
576 | } | |
577 | ||
578 | /* Set tls_offered if the response to EHLO specifies support for STARTTLS. */ | |
579 | #ifdef SUPPORT_TLS | |
580 | if (esmtp && !suppress_tls && tls_out.active < 0) | |
581 | { | |
582 | if (regex_STARTTLS == NULL) regex_STARTTLS = | |
583 | regex_must_compile(US"\\n250[\\s\\-]STARTTLS(\\s|\\n|$)", FALSE, TRUE); | |
584 | ||
585 | tls_offered = pcre_exec(regex_STARTTLS, NULL, CS responsebuffer, | |
586 | Ustrlen(responsebuffer), 0, PCRE_EOPT, NULL, 0) >= 0; | |
587 | } | |
588 | else | |
589 | tls_offered = FALSE; | |
590 | #endif | |
591 | } | |
592 | ||
593 | /* If TLS is available on this connection attempt to | |
594 | start up a TLS session, unless the host is in hosts_avoid_tls. If successful, | |
595 | send another EHLO - the server may give a different answer in secure mode. We | |
596 | use a separate buffer for reading the response to STARTTLS so that if it is | |
597 | negative, the original EHLO data is available for subsequent analysis, should | |
598 | the client not be required to use TLS. If the response is bad, copy the buffer | |
599 | for error analysis. */ | |
600 | ||
601 | #ifdef SUPPORT_TLS | |
602 | if (tls_offered && | |
603 | verify_check_this_host(&(ob->hosts_avoid_tls), NULL, host->name, | |
604 | host->address, NULL) != OK && | |
605 | verify_check_this_host(&(ob->hosts_verify_avoid_tls), NULL, host->name, | |
606 | host->address, NULL) != OK | |
607 | ) | |
608 | { | |
609 | uschar buffer2[4096]; | |
610 | if ( !smtps | |
611 | && !(done= smtp_write_command(&outblock, FALSE, "STARTTLS\r\n") >= 0)) | |
612 | goto SEND_FAILED; | |
613 | ||
614 | /* If there is an I/O error, transmission of this message is deferred. If | |
615 | there is a temporary rejection of STARRTLS and tls_tempfail_tryclear is | |
616 | false, we also defer. However, if there is a temporary rejection of STARTTLS | |
617 | and tls_tempfail_tryclear is true, or if there is an outright rejection of | |
618 | STARTTLS, we carry on. This means we will try to send the message in clear, | |
619 | unless the host is in hosts_require_tls (tested below). */ | |
620 | ||
621 | if (!smtps && !smtp_read_response(&inblock, buffer2, sizeof(buffer2), '2', | |
622 | ob->command_timeout)) | |
623 | { | |
624 | if (errno != 0 || buffer2[0] == 0 || | |
625 | (buffer2[0] == '4' && !ob->tls_tempfail_tryclear)) | |
626 | { | |
627 | Ustrncpy(responsebuffer, buffer2, sizeof(responsebuffer)); | |
628 | done= FALSE; | |
629 | goto RESPONSE_FAILED; | |
630 | } | |
631 | } | |
632 | ||
633 | /* STARTTLS accepted or ssl-on-connect: try to negotiate a TLS session. */ | |
634 | else | |
635 | { | |
636 | int oldtimeout = ob->command_timeout; | |
637 | int rc; | |
638 | ||
639 | ob->command_timeout = callout; | |
640 | rc = tls_client_start(inblock.sock, host, addr, ob); | |
641 | ob->command_timeout = oldtimeout; | |
642 | ||
643 | /* TLS negotiation failed; give an error. Try in clear on a new connection, | |
644 | if the options permit it for this host. */ | |
645 | if (rc != OK) | |
646 | { | |
647 | if (rc == DEFER && ob->tls_tempfail_tryclear && !smtps && | |
648 | verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name, | |
649 | host->address, NULL) != OK) | |
650 | { | |
651 | (void)close(inblock.sock); | |
652 | log_write(0, LOG_MAIN, "TLS session failure: delivering unencrypted " | |
653 | "to %s [%s] (not in hosts_require_tls)", host->name, host->address); | |
654 | suppress_tls = TRUE; | |
655 | goto tls_retry_connection; | |
656 | } | |
657 | /*save_errno = ERRNO_TLSFAILURE;*/ | |
658 | /*message = US"failure while setting up TLS session";*/ | |
659 | send_quit = FALSE; | |
660 | done= FALSE; | |
661 | goto TLS_FAILED; | |
662 | } | |
663 | ||
664 | /* TLS session is set up. Copy info for logging. */ | |
665 | addr->cipher = tls_out.cipher; | |
666 | addr->peerdn = tls_out.peerdn; | |
667 | ||
668 | /* For SMTPS we need to wait for the initial OK response, then do HELO. */ | |
669 | if (smtps) | |
670 | goto smtps_redo_greeting; | |
671 | ||
672 | /* For STARTTLS we need to redo EHLO */ | |
673 | goto tls_redo_helo; | |
674 | } | |
675 | } | |
676 | ||
677 | /* If the host is required to use a secure channel, ensure that we have one. */ | |
678 | if (tls_out.active < 0) | |
679 | if (verify_check_this_host(&(ob->hosts_require_tls), NULL, host->name, | |
680 | host->address, NULL) == OK) | |
681 | { | |
682 | /*save_errno = ERRNO_TLSREQUIRED;*/ | |
683 | log_write(0, LOG_MAIN, "a TLS session is required for %s [%s], but %s", | |
684 | host->name, host->address, | |
685 | tls_offered? "an attempt to start TLS failed" : "the server did not offer TLS support"); | |
686 | done= FALSE; | |
687 | goto TLS_FAILED; | |
688 | } | |
689 | ||
690 | #endif /*SUPPORT_TLS*/ | |
691 | ||
692 | done = TRUE; /* so far so good; have response to HELO */ | |
693 | ||
694 | /*XXX the EHLO response would be analyzed here for IGNOREQUOTA, SIZE, PIPELINING */ | |
695 | ||
696 | /* For now, transport_filter by cutthrough-delivery is not supported */ | |
697 | /* Need proper integration with the proper transport mechanism. */ | |
698 | if (cutthrough_delivery) | |
699 | { | |
700 | if (addr->transport->filter_command) | |
701 | { | |
702 | cutthrough_delivery= FALSE; | |
703 | HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of transport filter\n"); | |
704 | } | |
705 | #ifndef DISABLE_DKIM | |
706 | if (ob->dkim_domain) | |
707 | { | |
708 | cutthrough_delivery= FALSE; | |
709 | HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of DKIM signing\n"); | |
710 | } | |
711 | #endif | |
712 | } | |
713 | ||
714 | SEND_FAILED: | |
715 | RESPONSE_FAILED: | |
716 | TLS_FAILED: | |
717 | ; | |
718 | /* Clear down of the TLS, SMTP and TCP layers on error is handled below. */ | |
719 | ||
720 | /* Failure to accept HELO is cached; this blocks the whole domain for all | |
721 | senders. I/O errors and defer responses are not cached. */ | |
722 | ||
723 | if (!done) | |
724 | { | |
725 | *failure_ptr = US"mail"; /* At or before MAIL */ | |
726 | if (errno == 0 && responsebuffer[0] == '5') | |
727 | { | |
728 | setflag(addr, af_verify_nsfail); | |
729 | new_domain_record.result = ccache_reject; | |
730 | } | |
731 | } | |
732 | ||
733 | /* If we haven't authenticated, but are required to, give up. */ | |
734 | /* Try to AUTH */ | |
735 | ||
736 | else done = smtp_auth(responsebuffer, sizeof(responsebuffer), | |
737 | addr, host, ob, esmtp, &inblock, &outblock) == OK && | |
738 | ||
739 | /* Copy AUTH info for logging */ | |
740 | ( (addr->authenticator = client_authenticator), | |
741 | (addr->auth_id = client_authenticated_id), | |
742 | ||
743 | /* Build a mail-AUTH string (re-using responsebuffer for convenience */ | |
744 | !smtp_mail_auth_str(responsebuffer, sizeof(responsebuffer), addr, ob) | |
745 | ) && | |
746 | ||
747 | ( (addr->auth_sndr = client_authenticated_sender), | |
748 | ||
749 | /* Send the MAIL command */ | |
750 | (smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>%s\r\n", | |
751 | from_address, responsebuffer) >= 0) | |
752 | ) && | |
753 | ||
754 | smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), | |
755 | '2', callout); | |
756 | ||
757 | deliver_host = deliver_host_address = NULL; | |
758 | deliver_domain = save_deliver_domain; | |
759 | ||
760 | /* If the host does not accept MAIL FROM:<>, arrange to cache this | |
761 | information, but again, don't record anything for an I/O error or a defer. Do | |
762 | not cache rejections of MAIL when a non-empty sender has been used, because | |
763 | that blocks the whole domain for all senders. */ | |
764 | ||
765 | if (!done) | |
766 | { | |
767 | *failure_ptr = US"mail"; /* At or before MAIL */ | |
768 | if (errno == 0 && responsebuffer[0] == '5') | |
769 | { | |
770 | setflag(addr, af_verify_nsfail); | |
771 | if (from_address[0] == 0) | |
772 | new_domain_record.result = ccache_reject_mfnull; | |
773 | } | |
774 | } | |
775 | ||
776 | /* Otherwise, proceed to check a "random" address (if required), then the | |
777 | given address, and the postmaster address (if required). Between each check, | |
778 | issue RSET, because some servers accept only one recipient after MAIL | |
779 | FROM:<>. | |
780 | ||
781 | Before doing this, set the result in the domain cache record to "accept", | |
782 | unless its previous value was ccache_reject_mfnull. In that case, the domain | |
783 | rejects MAIL FROM:<> and we want to continue to remember that. When that is | |
784 | the case, we have got here only in the case of a recipient verification with | |
785 | a non-null sender. */ | |
786 | ||
787 | else | |
788 | { | |
789 | new_domain_record.result = | |
790 | (old_domain_cache_result == ccache_reject_mfnull)? | |
791 | ccache_reject_mfnull: ccache_accept; | |
792 | ||
793 | /* Do the random local part check first */ | |
794 | ||
795 | if (random_local_part != NULL) | |
796 | { | |
797 | uschar randombuffer[1024]; | |
798 | BOOL random_ok = | |
799 | smtp_write_command(&outblock, FALSE, | |
800 | "RCPT TO:<%.1000s@%.1000s>\r\n", random_local_part, | |
801 | addr->domain) >= 0 && | |
802 | smtp_read_response(&inblock, randombuffer, | |
803 | sizeof(randombuffer), '2', callout); | |
804 | ||
805 | /* Remember when we last did a random test */ | |
806 | ||
807 | new_domain_record.random_stamp = time(NULL); | |
808 | ||
809 | /* If accepted, we aren't going to do any further tests below. */ | |
810 | ||
811 | if (random_ok) | |
812 | { | |
813 | new_domain_record.random_result = ccache_accept; | |
814 | } | |
815 | ||
816 | /* Otherwise, cache a real negative response, and get back to the right | |
817 | state to send RCPT. Unless there's some problem such as a dropped | |
818 | connection, we expect to succeed, because the commands succeeded above. */ | |
819 | ||
820 | else if (errno == 0) | |
821 | { | |
822 | if (randombuffer[0] == '5') | |
823 | new_domain_record.random_result = ccache_reject; | |
824 | ||
825 | done = | |
826 | smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 && | |
827 | smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), | |
828 | '2', callout) && | |
829 | ||
830 | smtp_write_command(&outblock, FALSE, "MAIL FROM:<%s>\r\n", | |
831 | from_address) >= 0 && | |
832 | smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), | |
833 | '2', callout); | |
834 | } | |
835 | else done = FALSE; /* Some timeout/connection problem */ | |
836 | } /* Random check */ | |
837 | ||
838 | /* If the host is accepting all local parts, as determined by the "random" | |
839 | check, we don't need to waste time doing any further checking. */ | |
840 | ||
841 | if (new_domain_record.random_result != ccache_accept && done) | |
842 | { | |
843 | /* Get the rcpt_include_affixes flag from the transport if there is one, | |
844 | but assume FALSE if there is not. */ | |
845 | ||
846 | done = | |
847 | smtp_write_command(&outblock, FALSE, "RCPT TO:<%.1000s>\r\n", | |
848 | transport_rcpt_address(addr, | |
849 | (addr->transport == NULL)? FALSE : | |
850 | addr->transport->rcpt_include_affixes)) >= 0 && | |
851 | smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), | |
852 | '2', callout); | |
853 | ||
854 | if (done) | |
855 | new_address_record.result = ccache_accept; | |
856 | else if (errno == 0 && responsebuffer[0] == '5') | |
857 | { | |
858 | *failure_ptr = US"recipient"; | |
859 | new_address_record.result = ccache_reject; | |
860 | } | |
861 | ||
862 | /* Do postmaster check if requested; if a full check is required, we | |
863 | check for RCPT TO:<postmaster> (no domain) in accordance with RFC 821. */ | |
864 | ||
865 | if (done && pm_mailfrom != NULL) | |
866 | { | |
867 | /*XXX not suitable for cutthrough - sequencing problems */ | |
868 | cutthrough_delivery= FALSE; | |
869 | HDEBUG(D_acl|D_v) debug_printf("Cutthrough cancelled by presence of postmaster verify\n"); | |
870 | ||
871 | done = | |
872 | smtp_write_command(&outblock, FALSE, "RSET\r\n") >= 0 && | |
873 | smtp_read_response(&inblock, responsebuffer, | |
874 | sizeof(responsebuffer), '2', callout) && | |
875 | ||
876 | smtp_write_command(&outblock, FALSE, | |
877 | "MAIL FROM:<%s>\r\n", pm_mailfrom) >= 0 && | |
878 | smtp_read_response(&inblock, responsebuffer, | |
879 | sizeof(responsebuffer), '2', callout) && | |
880 | ||
881 | /* First try using the current domain */ | |
882 | ||
883 | (( | |
884 | smtp_write_command(&outblock, FALSE, | |
885 | "RCPT TO:<postmaster@%.1000s>\r\n", addr->domain) >= 0 && | |
886 | smtp_read_response(&inblock, responsebuffer, | |
887 | sizeof(responsebuffer), '2', callout) | |
888 | ) | |
889 | ||
890 | || | |
891 | ||
892 | /* If that doesn't work, and a full check is requested, | |
893 | try without the domain. */ | |
894 | ||
895 | ( | |
896 | (options & vopt_callout_fullpm) != 0 && | |
897 | smtp_write_command(&outblock, FALSE, | |
898 | "RCPT TO:<postmaster>\r\n") >= 0 && | |
899 | smtp_read_response(&inblock, responsebuffer, | |
900 | sizeof(responsebuffer), '2', callout) | |
901 | )); | |
902 | ||
903 | /* Sort out the cache record */ | |
904 | ||
905 | new_domain_record.postmaster_stamp = time(NULL); | |
906 | ||
907 | if (done) | |
908 | new_domain_record.postmaster_result = ccache_accept; | |
909 | else if (errno == 0 && responsebuffer[0] == '5') | |
910 | { | |
911 | *failure_ptr = US"postmaster"; | |
912 | setflag(addr, af_verify_pmfail); | |
913 | new_domain_record.postmaster_result = ccache_reject; | |
914 | } | |
915 | } | |
916 | } /* Random not accepted */ | |
917 | } /* MAIL FROM: accepted */ | |
918 | ||
919 | /* For any failure of the main check, other than a negative response, we just | |
920 | close the connection and carry on. We can identify a negative response by the | |
921 | fact that errno is zero. For I/O errors it will be non-zero | |
922 | ||
923 | Set up different error texts for logging and for sending back to the caller | |
924 | as an SMTP response. Log in all cases, using a one-line format. For sender | |
925 | callouts, give a full response to the caller, but for recipient callouts, | |
926 | don't give the IP address because this may be an internal host whose identity | |
927 | is not to be widely broadcast. */ | |
928 | ||
929 | if (!done) | |
930 | { | |
931 | if (errno == ETIMEDOUT) | |
932 | { | |
933 | HDEBUG(D_verify) debug_printf("SMTP timeout\n"); | |
934 | send_quit = FALSE; | |
935 | } | |
936 | else if (errno == 0) | |
937 | { | |
938 | if (*responsebuffer == 0) Ustrcpy(responsebuffer, US"connection dropped"); | |
939 | ||
940 | addr->message = | |
941 | string_sprintf("response to \"%s\" from %s [%s] was: %s", | |
942 | big_buffer, host->name, host->address, | |
943 | string_printing(responsebuffer)); | |
944 | ||
945 | addr->user_message = is_recipient? | |
946 | string_sprintf("Callout verification failed:\n%s", responsebuffer) | |
947 | : | |
948 | string_sprintf("Called: %s\nSent: %s\nResponse: %s", | |
949 | host->address, big_buffer, responsebuffer); | |
950 | ||
951 | /* Hard rejection ends the process */ | |
952 | ||
953 | if (responsebuffer[0] == '5') /* Address rejected */ | |
954 | { | |
955 | yield = FAIL; | |
956 | done = TRUE; | |
957 | } | |
958 | } | |
959 | } | |
960 | ||
961 | /* End the SMTP conversation and close the connection. */ | |
962 | ||
963 | /* Cutthrough - on a successfull connect and recipient-verify with use-sender | |
964 | and we have no cutthrough conn so far | |
965 | here is where we want to leave the conn open */ | |
966 | if ( cutthrough_delivery | |
967 | && done | |
968 | && yield == OK | |
969 | && (options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == vopt_callout_recipsender | |
970 | && !random_local_part | |
971 | && !pm_mailfrom | |
972 | && cutthrough_fd < 0 | |
973 | ) | |
974 | { | |
975 | cutthrough_fd= outblock.sock; /* We assume no buffer in use in the outblock */ | |
976 | cutthrough_addr = *addr; /* Save the address_item for later logging */ | |
977 | cutthrough_addr.next = NULL; | |
978 | cutthrough_addr.host_used = store_get(sizeof(host_item)); | |
979 | cutthrough_addr.host_used->name = host->name; | |
980 | cutthrough_addr.host_used->address = host->address; | |
981 | cutthrough_addr.host_used->port = port; | |
982 | if (addr->parent) | |
983 | *(cutthrough_addr.parent = store_get(sizeof(address_item)))= *addr->parent; | |
984 | ctblock.buffer = ctbuffer; | |
985 | ctblock.buffersize = sizeof(ctbuffer); | |
986 | ctblock.ptr = ctbuffer; | |
987 | /* ctblock.cmd_count = 0; ctblock.authenticating = FALSE; */ | |
988 | ctblock.sock = cutthrough_fd; | |
989 | } | |
990 | else | |
991 | { | |
992 | /* Ensure no cutthrough on multiple address verifies */ | |
993 | if (options & vopt_callout_recipsender) | |
994 | cancel_cutthrough_connection("multiple verify calls"); | |
995 | if (send_quit) (void)smtp_write_command(&outblock, FALSE, "QUIT\r\n"); | |
996 | ||
997 | #ifdef SUPPORT_TLS | |
998 | tls_close(FALSE, TRUE); | |
999 | #endif | |
1000 | (void)close(inblock.sock); | |
1001 | } | |
1002 | ||
1003 | } /* Loop through all hosts, while !done */ | |
1004 | } | |
1005 | ||
1006 | /* If we get here with done == TRUE, a successful callout happened, and yield | |
1007 | will be set OK or FAIL according to the response to the RCPT command. | |
1008 | Otherwise, we looped through the hosts but couldn't complete the business. | |
1009 | However, there may be domain-specific information to cache in both cases. | |
1010 | ||
1011 | The value of the result field in the new_domain record is ccache_unknown if | |
1012 | there was an error before or with MAIL FROM:, and errno was not zero, | |
1013 | implying some kind of I/O error. We don't want to write the cache in that case. | |
1014 | Otherwise the value is ccache_accept, ccache_reject, or ccache_reject_mfnull. */ | |
1015 | ||
1016 | if (!callout_no_cache && new_domain_record.result != ccache_unknown) | |
1017 | { | |
1018 | if ((dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE)) | |
1019 | == NULL) | |
1020 | { | |
1021 | HDEBUG(D_verify) debug_printf("callout cache: not available\n"); | |
1022 | } | |
1023 | else | |
1024 | { | |
1025 | (void)dbfn_write(dbm_file, addr->domain, &new_domain_record, | |
1026 | (int)sizeof(dbdata_callout_cache)); | |
1027 | HDEBUG(D_verify) debug_printf("wrote callout cache domain record:\n" | |
1028 | " result=%d postmaster=%d random=%d\n", | |
1029 | new_domain_record.result, | |
1030 | new_domain_record.postmaster_result, | |
1031 | new_domain_record.random_result); | |
1032 | } | |
1033 | } | |
1034 | ||
1035 | /* If a definite result was obtained for the callout, cache it unless caching | |
1036 | is disabled. */ | |
1037 | ||
1038 | if (done) | |
1039 | { | |
1040 | if (!callout_no_cache && new_address_record.result != ccache_unknown) | |
1041 | { | |
1042 | if (dbm_file == NULL) | |
1043 | dbm_file = dbfn_open(US"callout", O_RDWR|O_CREAT, &dbblock, FALSE); | |
1044 | if (dbm_file == NULL) | |
1045 | { | |
1046 | HDEBUG(D_verify) debug_printf("no callout cache available\n"); | |
1047 | } | |
1048 | else | |
1049 | { | |
1050 | (void)dbfn_write(dbm_file, address_key, &new_address_record, | |
1051 | (int)sizeof(dbdata_callout_cache_address)); | |
1052 | HDEBUG(D_verify) debug_printf("wrote %s callout cache address record\n", | |
1053 | (new_address_record.result == ccache_accept)? "positive" : "negative"); | |
1054 | } | |
1055 | } | |
1056 | } /* done */ | |
1057 | ||
1058 | /* Failure to connect to any host, or any response other than 2xx or 5xx is a | |
1059 | temporary error. If there was only one host, and a response was received, leave | |
1060 | it alone if supplying details. Otherwise, give a generic response. */ | |
1061 | ||
1062 | else /* !done */ | |
1063 | { | |
1064 | uschar *dullmsg = string_sprintf("Could not complete %s verify callout", | |
1065 | is_recipient? "recipient" : "sender"); | |
1066 | yield = DEFER; | |
1067 | ||
1068 | if (host_list->next != NULL || addr->message == NULL) addr->message = dullmsg; | |
1069 | ||
1070 | addr->user_message = (!smtp_return_error_details)? dullmsg : | |
1071 | string_sprintf("%s for <%s>.\n" | |
1072 | "The mail server(s) for the domain may be temporarily unreachable, or\n" | |
1073 | "they may be permanently unreachable from this server. In the latter case,\n%s", | |
1074 | dullmsg, addr->address, | |
1075 | is_recipient? | |
1076 | "the address will never be accepted." | |
1077 | : | |
1078 | "you need to change the address or create an MX record for its domain\n" | |
1079 | "if it is supposed to be generally accessible from the Internet.\n" | |
1080 | "Talk to your mail administrator for details."); | |
1081 | ||
1082 | /* Force a specific error code */ | |
1083 | ||
1084 | addr->basic_errno = ERRNO_CALLOUTDEFER; | |
1085 | } | |
1086 | ||
1087 | /* Come here from within the cache-reading code on fast-track exit. */ | |
1088 | ||
1089 | END_CALLOUT: | |
1090 | if (dbm_file != NULL) dbfn_close(dbm_file); | |
1091 | return yield; | |
1092 | } | |
1093 | ||
1094 | ||
1095 | ||
1096 | /* Called after recipient-acl to get a cutthrough connection open when | |
1097 | one was requested and a recipient-verify wasn't subsequently done. | |
1098 | */ | |
1099 | void | |
1100 | open_cutthrough_connection( address_item * addr ) | |
1101 | { | |
1102 | address_item addr2; | |
1103 | ||
1104 | /* Use a recipient-verify-callout to set up the cutthrough connection. */ | |
1105 | /* We must use a copy of the address for verification, because it might | |
1106 | get rewritten. */ | |
1107 | ||
1108 | addr2 = *addr; | |
1109 | HDEBUG(D_acl) debug_printf("----------- start cutthrough setup ------------\n"); | |
1110 | (void) verify_address(&addr2, NULL, | |
1111 | vopt_is_recipient | vopt_callout_recipsender | vopt_callout_no_cache, | |
1112 | CUTTHROUGH_CMD_TIMEOUT, -1, -1, | |
1113 | NULL, NULL, NULL); | |
1114 | HDEBUG(D_acl) debug_printf("----------- end cutthrough setup ------------\n"); | |
1115 | return; | |
1116 | } | |
1117 | ||
1118 | ||
1119 | ||
1120 | /* Send given number of bytes from the buffer */ | |
1121 | static BOOL | |
1122 | cutthrough_send(int n) | |
1123 | { | |
1124 | if(cutthrough_fd < 0) | |
1125 | return TRUE; | |
1126 | ||
1127 | if( | |
1128 | #ifdef SUPPORT_TLS | |
1129 | (tls_out.active == cutthrough_fd) ? tls_write(FALSE, ctblock.buffer, n) : | |
1130 | #endif | |
1131 | send(cutthrough_fd, ctblock.buffer, n, 0) > 0 | |
1132 | ) | |
1133 | { | |
1134 | transport_count += n; | |
1135 | ctblock.ptr= ctblock.buffer; | |
1136 | return TRUE; | |
1137 | } | |
1138 | ||
1139 | HDEBUG(D_transport|D_acl) debug_printf("cutthrough_send failed: %s\n", strerror(errno)); | |
1140 | return FALSE; | |
1141 | } | |
1142 | ||
1143 | ||
1144 | ||
1145 | static BOOL | |
1146 | _cutthrough_puts(uschar * cp, int n) | |
1147 | { | |
1148 | while(n--) | |
1149 | { | |
1150 | if(ctblock.ptr >= ctblock.buffer+ctblock.buffersize) | |
1151 | if(!cutthrough_send(ctblock.buffersize)) | |
1152 | return FALSE; | |
1153 | ||
1154 | *ctblock.ptr++ = *cp++; | |
1155 | } | |
1156 | return TRUE; | |
1157 | } | |
1158 | ||
1159 | /* Buffered output of counted data block. Return boolean success */ | |
1160 | BOOL | |
1161 | cutthrough_puts(uschar * cp, int n) | |
1162 | { | |
1163 | if (cutthrough_fd < 0) return TRUE; | |
1164 | if (_cutthrough_puts(cp, n)) return TRUE; | |
1165 | cancel_cutthrough_connection("transmit failed"); | |
1166 | return FALSE; | |
1167 | } | |
1168 | ||
1169 | ||
1170 | static BOOL | |
1171 | _cutthrough_flush_send( void ) | |
1172 | { | |
1173 | int n= ctblock.ptr-ctblock.buffer; | |
1174 | ||
1175 | if(n>0) | |
1176 | if(!cutthrough_send(n)) | |
1177 | return FALSE; | |
1178 | return TRUE; | |
1179 | } | |
1180 | ||
1181 | ||
1182 | /* Send out any bufferred output. Return boolean success. */ | |
1183 | BOOL | |
1184 | cutthrough_flush_send( void ) | |
1185 | { | |
1186 | if (_cutthrough_flush_send()) return TRUE; | |
1187 | cancel_cutthrough_connection("transmit failed"); | |
1188 | return FALSE; | |
1189 | } | |
1190 | ||
1191 | ||
1192 | BOOL | |
1193 | cutthrough_put_nl( void ) | |
1194 | { | |
1195 | return cutthrough_puts(US"\r\n", 2); | |
1196 | } | |
1197 | ||
1198 | ||
1199 | /* Get and check response from cutthrough target */ | |
1200 | static uschar | |
1201 | cutthrough_response(char expect, uschar ** copy) | |
1202 | { | |
1203 | smtp_inblock inblock; | |
1204 | uschar inbuffer[4096]; | |
1205 | uschar responsebuffer[4096]; | |
1206 | ||
1207 | inblock.buffer = inbuffer; | |
1208 | inblock.buffersize = sizeof(inbuffer); | |
1209 | inblock.ptr = inbuffer; | |
1210 | inblock.ptrend = inbuffer; | |
1211 | inblock.sock = cutthrough_fd; | |
1212 | /* this relies on (inblock.sock == tls_out.active) */ | |
1213 | if(!smtp_read_response(&inblock, responsebuffer, sizeof(responsebuffer), expect, CUTTHROUGH_DATA_TIMEOUT)) | |
1214 | cancel_cutthrough_connection("target timeout on read"); | |
1215 | ||
1216 | if(copy != NULL) | |
1217 | { | |
1218 | uschar * cp; | |
1219 | *copy= cp= string_copy(responsebuffer); | |
1220 | /* Trim the trailing end of line */ | |
1221 | cp += Ustrlen(responsebuffer); | |
1222 | if(cp > *copy && cp[-1] == '\n') *--cp = '\0'; | |
1223 | if(cp > *copy && cp[-1] == '\r') *--cp = '\0'; | |
1224 | } | |
1225 | ||
1226 | return responsebuffer[0]; | |
1227 | } | |
1228 | ||
1229 | ||
1230 | /* Negotiate dataphase with the cutthrough target, returning success boolean */ | |
1231 | BOOL | |
1232 | cutthrough_predata( void ) | |
1233 | { | |
1234 | if(cutthrough_fd < 0) | |
1235 | return FALSE; | |
1236 | ||
1237 | HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> DATA\n"); | |
1238 | cutthrough_puts(US"DATA\r\n", 6); | |
1239 | cutthrough_flush_send(); | |
1240 | ||
1241 | /* Assume nothing buffered. If it was it gets ignored. */ | |
1242 | return cutthrough_response('3', NULL) == '3'; | |
1243 | } | |
1244 | ||
1245 | ||
1246 | /* fd and use_crlf args only to match write_chunk() */ | |
1247 | static BOOL | |
1248 | cutthrough_write_chunk(int fd, uschar * s, int len, BOOL use_crlf) | |
1249 | { | |
1250 | uschar * s2; | |
1251 | while(s && (s2 = Ustrchr(s, '\n'))) | |
1252 | { | |
1253 | if(!cutthrough_puts(s, s2-s) || !cutthrough_put_nl()) | |
1254 | return FALSE; | |
1255 | s = s2+1; | |
1256 | } | |
1257 | return TRUE; | |
1258 | } | |
1259 | ||
1260 | ||
1261 | /* Buffered send of headers. Return success boolean. */ | |
1262 | /* Expands newlines to wire format (CR,NL). */ | |
1263 | /* Also sends header-terminating blank line. */ | |
1264 | BOOL | |
1265 | cutthrough_headers_send( void ) | |
1266 | { | |
1267 | if(cutthrough_fd < 0) | |
1268 | return FALSE; | |
1269 | ||
1270 | /* We share a routine with the mainline transport to handle header add/remove/rewrites, | |
1271 | but having a separate buffered-output function (for now) | |
1272 | */ | |
1273 | HDEBUG(D_acl) debug_printf("----------- start cutthrough headers send -----------\n"); | |
1274 | ||
1275 | if (!transport_headers_send(&cutthrough_addr, cutthrough_fd, | |
1276 | cutthrough_addr.transport->add_headers, cutthrough_addr.transport->remove_headers, | |
1277 | &cutthrough_write_chunk, TRUE, | |
1278 | cutthrough_addr.transport->rewrite_rules, cutthrough_addr.transport->rewrite_existflags)) | |
1279 | return FALSE; | |
1280 | ||
1281 | HDEBUG(D_acl) debug_printf("----------- done cutthrough headers send ------------\n"); | |
1282 | return TRUE; | |
1283 | } | |
1284 | ||
1285 | ||
1286 | static void | |
1287 | close_cutthrough_connection( const char * why ) | |
1288 | { | |
1289 | if(cutthrough_fd >= 0) | |
1290 | { | |
1291 | /* We could be sending this after a bunch of data, but that is ok as | |
1292 | the only way to cancel the transfer in dataphase is to drop the tcp | |
1293 | conn before the final dot. | |
1294 | */ | |
1295 | ctblock.ptr = ctbuffer; | |
1296 | HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> QUIT\n"); | |
1297 | _cutthrough_puts(US"QUIT\r\n", 6); /* avoid recursion */ | |
1298 | _cutthrough_flush_send(); | |
1299 | /* No wait for response */ | |
1300 | ||
1301 | #ifdef SUPPORT_TLS | |
1302 | tls_close(FALSE, TRUE); | |
1303 | #endif | |
1304 | (void)close(cutthrough_fd); | |
1305 | cutthrough_fd= -1; | |
1306 | HDEBUG(D_acl) debug_printf("----------- cutthrough shutdown (%s) ------------\n", why); | |
1307 | } | |
1308 | ctblock.ptr = ctbuffer; | |
1309 | } | |
1310 | ||
1311 | void | |
1312 | cancel_cutthrough_connection( const char * why ) | |
1313 | { | |
1314 | close_cutthrough_connection(why); | |
1315 | cutthrough_delivery= FALSE; | |
1316 | } | |
1317 | ||
1318 | ||
1319 | ||
1320 | ||
1321 | /* Have senders final-dot. Send one to cutthrough target, and grab the response. | |
1322 | Log an OK response as a transmission. | |
1323 | Close the connection. | |
1324 | Return smtp response-class digit. | |
1325 | */ | |
1326 | uschar * | |
1327 | cutthrough_finaldot( void ) | |
1328 | { | |
1329 | HDEBUG(D_transport|D_acl|D_v) debug_printf(" SMTP>> .\n"); | |
1330 | ||
1331 | /* Assume data finshed with new-line */ | |
1332 | if(!cutthrough_puts(US".", 1) || !cutthrough_put_nl() || !cutthrough_flush_send()) | |
1333 | return cutthrough_addr.message; | |
1334 | ||
1335 | switch(cutthrough_response('2', &cutthrough_addr.message)) | |
1336 | { | |
1337 | case '2': | |
1338 | delivery_log(LOG_MAIN, &cutthrough_addr, (int)'>', NULL); | |
1339 | close_cutthrough_connection("delivered"); | |
1340 | break; | |
1341 | ||
1342 | case '4': | |
1343 | delivery_log(LOG_MAIN, &cutthrough_addr, 0, US"tmp-reject from cutthrough after DATA:"); | |
1344 | break; | |
1345 | ||
1346 | case '5': | |
1347 | delivery_log(LOG_MAIN|LOG_REJECT, &cutthrough_addr, 0, US"rejected after DATA:"); | |
1348 | break; | |
1349 | ||
1350 | default: | |
1351 | break; | |
1352 | } | |
1353 | return cutthrough_addr.message; | |
1354 | } | |
1355 | ||
1356 | ||
1357 | ||
1358 | /************************************************* | |
1359 | * Copy error to toplevel address * | |
1360 | *************************************************/ | |
1361 | ||
1362 | /* This function is used when a verify fails or defers, to ensure that the | |
1363 | failure or defer information is in the original toplevel address. This applies | |
1364 | when an address is redirected to a single new address, and the failure or | |
1365 | deferral happens to the child address. | |
1366 | ||
1367 | Arguments: | |
1368 | vaddr the verify address item | |
1369 | addr the final address item | |
1370 | yield FAIL or DEFER | |
1371 | ||
1372 | Returns: the value of YIELD | |
1373 | */ | |
1374 | ||
1375 | static int | |
1376 | copy_error(address_item *vaddr, address_item *addr, int yield) | |
1377 | { | |
1378 | if (addr != vaddr) | |
1379 | { | |
1380 | vaddr->message = addr->message; | |
1381 | vaddr->user_message = addr->user_message; | |
1382 | vaddr->basic_errno = addr->basic_errno; | |
1383 | vaddr->more_errno = addr->more_errno; | |
1384 | vaddr->p.address_data = addr->p.address_data; | |
1385 | copyflag(vaddr, addr, af_pass_message); | |
1386 | } | |
1387 | return yield; | |
1388 | } | |
1389 | ||
1390 | ||
1391 | ||
1392 | ||
1393 | /************************************************** | |
1394 | * printf that automatically handles TLS if needed * | |
1395 | ***************************************************/ | |
1396 | ||
1397 | /* This function is used by verify_address() as a substitute for all fprintf() | |
1398 | calls; a direct fprintf() will not produce output in a TLS SMTP session, such | |
1399 | as a response to an EXPN command. smtp_in.c makes smtp_printf available but | |
1400 | that assumes that we always use the smtp_out FILE* when not using TLS or the | |
1401 | ssl buffer when we are. Instead we take a FILE* parameter and check to see if | |
1402 | that is smtp_out; if so, smtp_printf() with TLS support, otherwise regular | |
1403 | fprintf(). | |
1404 | ||
1405 | Arguments: | |
1406 | f the candidate FILE* to write to | |
1407 | format format string | |
1408 | ... optional arguments | |
1409 | ||
1410 | Returns: | |
1411 | nothing | |
1412 | */ | |
1413 | ||
1414 | static void PRINTF_FUNCTION(2,3) | |
1415 | respond_printf(FILE *f, const char *format, ...) | |
1416 | { | |
1417 | va_list ap; | |
1418 | ||
1419 | va_start(ap, format); | |
1420 | if (smtp_out && (f == smtp_out)) | |
1421 | smtp_vprintf(format, ap); | |
1422 | else | |
1423 | vfprintf(f, format, ap); | |
1424 | va_end(ap); | |
1425 | } | |
1426 | ||
1427 | ||
1428 | ||
1429 | /************************************************* | |
1430 | * Verify an email address * | |
1431 | *************************************************/ | |
1432 | ||
1433 | /* This function is used both for verification (-bv and at other times) and | |
1434 | address testing (-bt), which is indicated by address_test_mode being set. | |
1435 | ||
1436 | Arguments: | |
1437 | vaddr contains the address to verify; the next field in this block | |
1438 | must be NULL | |
1439 | f if not NULL, write the result to this file | |
1440 | options various option bits: | |
1441 | vopt_fake_sender => this sender verify is not for the real | |
1442 | sender (it was verify=sender=xxxx or an address from a | |
1443 | header line) - rewriting must not change sender_address | |
1444 | vopt_is_recipient => this is a recipient address, otherwise | |
1445 | it's a sender address - this affects qualification and | |
1446 | rewriting and messages from callouts | |
1447 | vopt_qualify => qualify an unqualified address; else error | |
1448 | vopt_expn => called from SMTP EXPN command | |
1449 | vopt_success_on_redirect => when a new address is generated | |
1450 | the verification instantly succeeds | |
1451 | ||
1452 | These ones are used by do_callout() -- the options variable | |
1453 | is passed to it. | |
1454 | ||
1455 | vopt_callout_fullpm => if postmaster check, do full one | |
1456 | vopt_callout_no_cache => don't use callout cache | |
1457 | vopt_callout_random => do the "random" thing | |
1458 | vopt_callout_recipsender => use real sender for recipient | |
1459 | vopt_callout_recippmaster => use postmaster for recipient | |
1460 | ||
1461 | callout if > 0, specifies that callout is required, and gives timeout | |
1462 | for individual commands | |
1463 | callout_overall if > 0, gives overall timeout for the callout function; | |
1464 | if < 0, a default is used (see do_callout()) | |
1465 | callout_connect the connection timeout for callouts | |
1466 | se_mailfrom when callout is requested to verify a sender, use this | |
1467 | in MAIL FROM; NULL => "" | |
1468 | pm_mailfrom when callout is requested, if non-NULL, do the postmaster | |
1469 | thing and use this as the sender address (may be "") | |
1470 | ||
1471 | routed if not NULL, set TRUE if routing succeeded, so we can | |
1472 | distinguish between routing failed and callout failed | |
1473 | ||
1474 | Returns: OK address verified | |
1475 | FAIL address failed to verify | |
1476 | DEFER can't tell at present | |
1477 | */ | |
1478 | ||
1479 | int | |
1480 | verify_address(address_item *vaddr, FILE *f, int options, int callout, | |
1481 | int callout_overall, int callout_connect, uschar *se_mailfrom, | |
1482 | uschar *pm_mailfrom, BOOL *routed) | |
1483 | { | |
1484 | BOOL allok = TRUE; | |
1485 | BOOL full_info = (f == NULL)? FALSE : (debug_selector != 0); | |
1486 | BOOL is_recipient = (options & vopt_is_recipient) != 0; | |
1487 | BOOL expn = (options & vopt_expn) != 0; | |
1488 | BOOL success_on_redirect = (options & vopt_success_on_redirect) != 0; | |
1489 | int i; | |
1490 | int yield = OK; | |
1491 | int verify_type = expn? v_expn : | |
1492 | address_test_mode? v_none : | |
1493 | is_recipient? v_recipient : v_sender; | |
1494 | address_item *addr_list; | |
1495 | address_item *addr_new = NULL; | |
1496 | address_item *addr_remote = NULL; | |
1497 | address_item *addr_local = NULL; | |
1498 | address_item *addr_succeed = NULL; | |
1499 | uschar **failure_ptr = is_recipient? | |
1500 | &recipient_verify_failure : &sender_verify_failure; | |
1501 | uschar *ko_prefix, *cr; | |
1502 | uschar *address = vaddr->address; | |
1503 | uschar *save_sender; | |
1504 | uschar null_sender[] = { 0 }; /* Ensure writeable memory */ | |
1505 | ||
1506 | /* Clear, just in case */ | |
1507 | ||
1508 | *failure_ptr = NULL; | |
1509 | ||
1510 | /* Set up a prefix and suffix for error message which allow us to use the same | |
1511 | output statements both in EXPN mode (where an SMTP response is needed) and when | |
1512 | debugging with an output file. */ | |
1513 | ||
1514 | if (expn) | |
1515 | { | |
1516 | ko_prefix = US"553 "; | |
1517 | cr = US"\r"; | |
1518 | } | |
1519 | else ko_prefix = cr = US""; | |
1520 | ||
1521 | /* Add qualify domain if permitted; otherwise an unqualified address fails. */ | |
1522 | ||
1523 | if (parse_find_at(address) == NULL) | |
1524 | { | |
1525 | if ((options & vopt_qualify) == 0) | |
1526 | { | |
1527 | if (f != NULL) | |
1528 | respond_printf(f, "%sA domain is required for \"%s\"%s\n", | |
1529 | ko_prefix, address, cr); | |
1530 | *failure_ptr = US"qualify"; | |
1531 | return FAIL; | |
1532 | } | |
1533 | address = rewrite_address_qualify(address, is_recipient); | |
1534 | } | |
1535 | ||
1536 | DEBUG(D_verify) | |
1537 | { | |
1538 | debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); | |
1539 | debug_printf("%s %s\n", address_test_mode? "Testing" : "Verifying", address); | |
1540 | } | |
1541 | ||
1542 | /* Rewrite and report on it. Clear the domain and local part caches - these | |
1543 | may have been set by domains and local part tests during an ACL. */ | |
1544 | ||
1545 | if (global_rewrite_rules != NULL) | |
1546 | { | |
1547 | uschar *old = address; | |
1548 | address = rewrite_address(address, is_recipient, FALSE, | |
1549 | global_rewrite_rules, rewrite_existflags); | |
1550 | if (address != old) | |
1551 | { | |
1552 | for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->localpart_cache[i] = 0; | |
1553 | for (i = 0; i < (MAX_NAMED_LIST * 2)/32; i++) vaddr->domain_cache[i] = 0; | |
1554 | if (f != NULL && !expn) fprintf(f, "Address rewritten as: %s\n", address); | |
1555 | } | |
1556 | } | |
1557 | ||
1558 | /* If this is the real sender address, we must update sender_address at | |
1559 | this point, because it may be referred to in the routers. */ | |
1560 | ||
1561 | if ((options & (vopt_fake_sender|vopt_is_recipient)) == 0) | |
1562 | sender_address = address; | |
1563 | ||
1564 | /* If the address was rewritten to <> no verification can be done, and we have | |
1565 | to return OK. This rewriting is permitted only for sender addresses; for other | |
1566 | addresses, such rewriting fails. */ | |
1567 | ||
1568 | if (address[0] == 0) return OK; | |
1569 | ||
1570 | /* Flip the legacy TLS-related variables over to the outbound set in case | |
1571 | they're used in the context of a transport used by verification. Reset them | |
1572 | at exit from this routine. */ | |
1573 | ||
1574 | tls_modify_variables(&tls_out); | |
1575 | ||
1576 | /* Save a copy of the sender address for re-instating if we change it to <> | |
1577 | while verifying a sender address (a nice bit of self-reference there). */ | |
1578 | ||
1579 | save_sender = sender_address; | |
1580 | ||
1581 | /* Update the address structure with the possibly qualified and rewritten | |
1582 | address. Set it up as the starting address on the chain of new addresses. */ | |
1583 | ||
1584 | vaddr->address = address; | |
1585 | addr_new = vaddr; | |
1586 | ||
1587 | /* We need a loop, because an address can generate new addresses. We must also | |
1588 | cope with generated pipes and files at the top level. (See also the code and | |
1589 | comment in deliver.c.) However, it is usually the case that the router for | |
1590 | user's .forward files has its verify flag turned off. | |
1591 | ||
1592 | If an address generates more than one child, the loop is used only when | |
1593 | full_info is set, and this can only be set locally. Remote enquiries just get | |
1594 | information about the top level address, not anything that it generated. */ | |
1595 | ||
1596 | while (addr_new != NULL) | |
1597 | { | |
1598 | int rc; | |
1599 | address_item *addr = addr_new; | |
1600 | ||
1601 | addr_new = addr->next; | |
1602 | addr->next = NULL; | |
1603 | ||
1604 | DEBUG(D_verify) | |
1605 | { | |
1606 | debug_printf(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n"); | |
1607 | debug_printf("Considering %s\n", addr->address); | |
1608 | } | |
1609 | ||
1610 | /* Handle generated pipe, file or reply addresses. We don't get these | |
1611 | when handling EXPN, as it does only one level of expansion. */ | |
1612 | ||
1613 | if (testflag(addr, af_pfr)) | |
1614 | { | |
1615 | allok = FALSE; | |
1616 | if (f != NULL) | |
1617 | { | |
1618 | BOOL allow; | |
1619 | ||
1620 | if (addr->address[0] == '>') | |
1621 | { | |
1622 | allow = testflag(addr, af_allow_reply); | |
1623 | fprintf(f, "%s -> mail %s", addr->parent->address, addr->address + 1); | |
1624 | } | |
1625 | else | |
1626 | { | |
1627 | allow = (addr->address[0] == '|')? | |
1628 | testflag(addr, af_allow_pipe) : testflag(addr, af_allow_file); | |
1629 | fprintf(f, "%s -> %s", addr->parent->address, addr->address); | |
1630 | } | |
1631 | ||
1632 | if (addr->basic_errno == ERRNO_BADTRANSPORT) | |
1633 | fprintf(f, "\n*** Error in setting up pipe, file, or autoreply:\n" | |
1634 | "%s\n", addr->message); | |
1635 | else if (allow) | |
1636 | fprintf(f, "\n transport = %s\n", addr->transport->name); | |
1637 | else | |
1638 | fprintf(f, " *** forbidden ***\n"); | |
1639 | } | |
1640 | continue; | |
1641 | } | |
1642 | ||
1643 | /* Just in case some router parameter refers to it. */ | |
1644 | ||
1645 | return_path = (addr->p.errors_address != NULL)? | |
1646 | addr->p.errors_address : sender_address; | |
1647 | ||
1648 | /* Split the address into domain and local part, handling the %-hack if | |
1649 | necessary, and then route it. While routing a sender address, set | |
1650 | $sender_address to <> because that is what it will be if we were trying to | |
1651 | send a bounce to the sender. */ | |
1652 | ||
1653 | if (routed != NULL) *routed = FALSE; | |
1654 | if ((rc = deliver_split_address(addr)) == OK) | |
1655 | { | |
1656 | if (!is_recipient) sender_address = null_sender; | |
1657 | rc = route_address(addr, &addr_local, &addr_remote, &addr_new, | |
1658 | &addr_succeed, verify_type); | |
1659 | sender_address = save_sender; /* Put back the real sender */ | |
1660 | } | |
1661 | ||
1662 | /* If routing an address succeeded, set the flag that remembers, for use when | |
1663 | an ACL cached a sender verify (in case a callout fails). Then if routing set | |
1664 | up a list of hosts or the transport has a host list, and the callout option | |
1665 | is set, and we aren't in a host checking run, do the callout verification, | |
1666 | and set another flag that notes that a callout happened. */ | |
1667 | ||
1668 | if (rc == OK) | |
1669 | { | |
1670 | if (routed != NULL) *routed = TRUE; | |
1671 | if (callout > 0) | |
1672 | { | |
1673 | host_item *host_list = addr->host_list; | |
1674 | ||
1675 | /* Make up some data for use in the case where there is no remote | |
1676 | transport. */ | |
1677 | ||
1678 | transport_feedback tf = { | |
1679 | NULL, /* interface (=> any) */ | |
1680 | US"smtp", /* port */ | |
1681 | US"smtp", /* protocol */ | |
1682 | NULL, /* hosts */ | |
1683 | US"$smtp_active_hostname", /* helo_data */ | |
1684 | FALSE, /* hosts_override */ | |
1685 | FALSE, /* hosts_randomize */ | |
1686 | FALSE, /* gethostbyname */ | |
1687 | TRUE, /* qualify_single */ | |
1688 | FALSE /* search_parents */ | |
1689 | }; | |
1690 | ||
1691 | /* If verification yielded a remote transport, we want to use that | |
1692 | transport's options, so as to mimic what would happen if we were really | |
1693 | sending a message to this address. */ | |
1694 | ||
1695 | if (addr->transport != NULL && !addr->transport->info->local) | |
1696 | { | |
1697 | (void)(addr->transport->setup)(addr->transport, addr, &tf, 0, 0, NULL); | |
1698 | ||
1699 | /* If the transport has hosts and the router does not, or if the | |
1700 | transport is configured to override the router's hosts, we must build a | |
1701 | host list of the transport's hosts, and find the IP addresses */ | |
1702 | ||
1703 | if (tf.hosts != NULL && (host_list == NULL || tf.hosts_override)) | |
1704 | { | |
1705 | uschar *s; | |
1706 | uschar *save_deliver_domain = deliver_domain; | |
1707 | uschar *save_deliver_localpart = deliver_localpart; | |
1708 | ||
1709 | host_list = NULL; /* Ignore the router's hosts */ | |
1710 | ||
1711 | deliver_domain = addr->domain; | |
1712 | deliver_localpart = addr->local_part; | |
1713 | s = expand_string(tf.hosts); | |
1714 | deliver_domain = save_deliver_domain; | |
1715 | deliver_localpart = save_deliver_localpart; | |
1716 | ||
1717 | if (s == NULL) | |
1718 | { | |
1719 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand list of hosts " | |
1720 | "\"%s\" in %s transport for callout: %s", tf.hosts, | |
1721 | addr->transport->name, expand_string_message); | |
1722 | } | |
1723 | else | |
1724 | { | |
1725 | int flags; | |
1726 | uschar *canonical_name; | |
1727 | host_item *host, *nexthost; | |
1728 | host_build_hostlist(&host_list, s, tf.hosts_randomize); | |
1729 | ||
1730 | /* Just ignore failures to find a host address. If we don't manage | |
1731 | to find any addresses, the callout will defer. Note that more than | |
1732 | one address may be found for a single host, which will result in | |
1733 | additional host items being inserted into the chain. Hence we must | |
1734 | save the next host first. */ | |
1735 | ||
1736 | flags = HOST_FIND_BY_A; | |
1737 | if (tf.qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE; | |
1738 | if (tf.search_parents) flags |= HOST_FIND_SEARCH_PARENTS; | |
1739 | ||
1740 | for (host = host_list; host != NULL; host = nexthost) | |
1741 | { | |
1742 | nexthost = host->next; | |
1743 | if (tf.gethostbyname || | |
1744 | string_is_ip_address(host->name, NULL) != 0) | |
1745 | (void)host_find_byname(host, NULL, flags, &canonical_name, TRUE); | |
1746 | else | |
1747 | { | |
1748 | uschar * d_request = NULL, * d_require = NULL; | |
1749 | if (Ustrcmp(addr->transport->driver_name, "smtp") == 0) | |
1750 | { | |
1751 | smtp_transport_options_block * ob = | |
1752 | (smtp_transport_options_block *) | |
1753 | addr->transport->options_block; | |
1754 | d_request = ob->dnssec_request_domains; | |
1755 | d_require = ob->dnssec_require_domains; | |
1756 | } | |
1757 | ||
1758 | (void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL, | |
1759 | d_request, d_require, &canonical_name, NULL); | |
1760 | } | |
1761 | } | |
1762 | } | |
1763 | } | |
1764 | } | |
1765 | ||
1766 | /* Can only do a callout if we have at least one host! If the callout | |
1767 | fails, it will have set ${sender,recipient}_verify_failure. */ | |
1768 | ||
1769 | if (host_list != NULL) | |
1770 | { | |
1771 | HDEBUG(D_verify) debug_printf("Attempting full verification using callout\n"); | |
1772 | if (host_checking && !host_checking_callout) | |
1773 | { | |
1774 | HDEBUG(D_verify) | |
1775 | debug_printf("... callout omitted by default when host testing\n" | |
1776 | "(Use -bhc if you want the callouts to happen.)\n"); | |
1777 | } | |
1778 | else | |
1779 | { | |
1780 | #ifdef SUPPORT_TLS | |
1781 | deliver_set_expansions(addr); | |
1782 | #endif | |
1783 | rc = do_callout(addr, host_list, &tf, callout, callout_overall, | |
1784 | callout_connect, options, se_mailfrom, pm_mailfrom); | |
1785 | } | |
1786 | } | |
1787 | else | |
1788 | { | |
1789 | HDEBUG(D_verify) debug_printf("Cannot do callout: neither router nor " | |
1790 | "transport provided a host list\n"); | |
1791 | } | |
1792 | } | |
1793 | } | |
1794 | ||
1795 | /* Otherwise, any failure is a routing failure */ | |
1796 | ||
1797 | else *failure_ptr = US"route"; | |
1798 | ||
1799 | /* A router may return REROUTED if it has set up a child address as a result | |
1800 | of a change of domain name (typically from widening). In this case we always | |
1801 | want to continue to verify the new child. */ | |
1802 | ||
1803 | if (rc == REROUTED) continue; | |
1804 | ||
1805 | /* Handle hard failures */ | |
1806 | ||
1807 | if (rc == FAIL) | |
1808 | { | |
1809 | allok = FALSE; | |
1810 | if (f != NULL) | |
1811 | { | |
1812 | address_item *p = addr->parent; | |
1813 | ||
1814 | respond_printf(f, "%s%s %s", ko_prefix, | |
1815 | full_info? addr->address : address, | |
1816 | address_test_mode? "is undeliverable" : "failed to verify"); | |
1817 | if (!expn && admin_user) | |
1818 | { | |
1819 | if (addr->basic_errno > 0) | |
1820 | respond_printf(f, ": %s", strerror(addr->basic_errno)); | |
1821 | if (addr->message != NULL) | |
1822 | respond_printf(f, ": %s", addr->message); | |
1823 | } | |
1824 | ||
1825 | /* Show parents iff doing full info */ | |
1826 | ||
1827 | if (full_info) while (p != NULL) | |
1828 | { | |
1829 | respond_printf(f, "%s\n <-- %s", cr, p->address); | |
1830 | p = p->parent; | |
1831 | } | |
1832 | respond_printf(f, "%s\n", cr); | |
1833 | } | |
1834 | cancel_cutthrough_connection("routing hard fail"); | |
1835 | ||
1836 | if (!full_info) | |
1837 | { | |
1838 | yield = copy_error(vaddr, addr, FAIL); | |
1839 | goto out; | |
1840 | } | |
1841 | else yield = FAIL; | |
1842 | } | |
1843 | ||
1844 | /* Soft failure */ | |
1845 | ||
1846 | else if (rc == DEFER) | |
1847 | { | |
1848 | allok = FALSE; | |
1849 | if (f != NULL) | |
1850 | { | |
1851 | address_item *p = addr->parent; | |
1852 | respond_printf(f, "%s%s cannot be resolved at this time", ko_prefix, | |
1853 | full_info? addr->address : address); | |
1854 | if (!expn && admin_user) | |
1855 | { | |
1856 | if (addr->basic_errno > 0) | |
1857 | respond_printf(f, ": %s", strerror(addr->basic_errno)); | |
1858 | if (addr->message != NULL) | |
1859 | respond_printf(f, ": %s", addr->message); | |
1860 | else if (addr->basic_errno <= 0) | |
1861 | respond_printf(f, ": unknown error"); | |
1862 | } | |
1863 | ||
1864 | /* Show parents iff doing full info */ | |
1865 | ||
1866 | if (full_info) while (p != NULL) | |
1867 | { | |
1868 | respond_printf(f, "%s\n <-- %s", cr, p->address); | |
1869 | p = p->parent; | |
1870 | } | |
1871 | respond_printf(f, "%s\n", cr); | |
1872 | } | |
1873 | cancel_cutthrough_connection("routing soft fail"); | |
1874 | ||
1875 | if (!full_info) | |
1876 | { | |
1877 | yield = copy_error(vaddr, addr, DEFER); | |
1878 | goto out; | |
1879 | } | |
1880 | else if (yield == OK) yield = DEFER; | |
1881 | } | |
1882 | ||
1883 | /* If we are handling EXPN, we do not want to continue to route beyond | |
1884 | the top level (whose address is in "address"). */ | |
1885 | ||
1886 | else if (expn) | |
1887 | { | |
1888 | uschar *ok_prefix = US"250-"; | |
1889 | if (addr_new == NULL) | |
1890 | { | |
1891 | if (addr_local == NULL && addr_remote == NULL) | |
1892 | respond_printf(f, "250 mail to <%s> is discarded\r\n", address); | |
1893 | else | |
1894 | respond_printf(f, "250 <%s>\r\n", address); | |
1895 | } | |
1896 | else while (addr_new != NULL) | |
1897 | { | |
1898 | address_item *addr2 = addr_new; | |
1899 | addr_new = addr2->next; | |
1900 | if (addr_new == NULL) ok_prefix = US"250 "; | |
1901 | respond_printf(f, "%s<%s>\r\n", ok_prefix, addr2->address); | |
1902 | } | |
1903 | yield = OK; | |
1904 | goto out; | |
1905 | } | |
1906 | ||
1907 | /* Successful routing other than EXPN. */ | |
1908 | ||
1909 | else | |
1910 | { | |
1911 | /* Handle successful routing when short info wanted. Otherwise continue for | |
1912 | other (generated) addresses. Short info is the operational case. Full info | |
1913 | can be requested only when debug_selector != 0 and a file is supplied. | |
1914 | ||
1915 | There is a conflict between the use of aliasing as an alternate email | |
1916 | address, and as a sort of mailing list. If an alias turns the incoming | |
1917 | address into just one address (e.g. J.Caesar->jc44) you may well want to | |
1918 | carry on verifying the generated address to ensure it is valid when | |
1919 | checking incoming mail. If aliasing generates multiple addresses, you | |
1920 | probably don't want to do this. Exim therefore treats the generation of | |
1921 | just a single new address as a special case, and continues on to verify the | |
1922 | generated address. */ | |
1923 | ||
1924 | if (!full_info && /* Stop if short info wanted AND */ | |
1925 | (((addr_new == NULL || /* No new address OR */ | |
1926 | addr_new->next != NULL || /* More than one new address OR */ | |
1927 | testflag(addr_new, af_pfr))) /* New address is pfr */ | |
1928 | || /* OR */ | |
1929 | (addr_new != NULL && /* At least one new address AND */ | |
1930 | success_on_redirect))) /* success_on_redirect is set */ | |
1931 | { | |
1932 | if (f != NULL) fprintf(f, "%s %s\n", address, | |
1933 | address_test_mode? "is deliverable" : "verified"); | |
1934 | ||
1935 | /* If we have carried on to verify a child address, we want the value | |
1936 | of $address_data to be that of the child */ | |
1937 | ||
1938 | vaddr->p.address_data = addr->p.address_data; | |
1939 | yield = OK; | |
1940 | goto out; | |
1941 | } | |
1942 | } | |
1943 | } /* Loop for generated addresses */ | |
1944 | ||
1945 | /* Display the full results of the successful routing, including any generated | |
1946 | addresses. Control gets here only when full_info is set, which requires f not | |
1947 | to be NULL, and this occurs only when a top-level verify is called with the | |
1948 | debugging switch on. | |
1949 | ||
1950 | If there are no local and no remote addresses, and there were no pipes, files, | |
1951 | or autoreplies, and there were no errors or deferments, the message is to be | |
1952 | discarded, usually because of the use of :blackhole: in an alias file. */ | |
1953 | ||
1954 | if (allok && addr_local == NULL && addr_remote == NULL) | |
1955 | { | |
1956 | fprintf(f, "mail to %s is discarded\n", address); | |
1957 | goto out; | |
1958 | } | |
1959 | ||
1960 | for (addr_list = addr_local, i = 0; i < 2; addr_list = addr_remote, i++) | |
1961 | { | |
1962 | while (addr_list != NULL) | |
1963 | { | |
1964 | address_item *addr = addr_list; | |
1965 | address_item *p = addr->parent; | |
1966 | addr_list = addr->next; | |
1967 | ||
1968 | fprintf(f, "%s", CS addr->address); | |
1969 | #ifdef EXPERIMENTAL_SRS | |
1970 | if(addr->p.srs_sender) | |
1971 | fprintf(f, " [srs = %s]", addr->p.srs_sender); | |
1972 | #endif | |
1973 | ||
1974 | /* If the address is a duplicate, show something about it. */ | |
1975 | ||
1976 | if (!testflag(addr, af_pfr)) | |
1977 | { | |
1978 | tree_node *tnode; | |
1979 | if ((tnode = tree_search(tree_duplicates, addr->unique)) != NULL) | |
1980 | fprintf(f, " [duplicate, would not be delivered]"); | |
1981 | else tree_add_duplicate(addr->unique, addr); | |
1982 | } | |
1983 | ||
1984 | /* Now show its parents */ | |
1985 | ||
1986 | while (p != NULL) | |
1987 | { | |
1988 | fprintf(f, "\n <-- %s", p->address); | |
1989 | p = p->parent; | |
1990 | } | |
1991 | fprintf(f, "\n "); | |
1992 | ||
1993 | /* Show router, and transport */ | |
1994 | ||
1995 | fprintf(f, "router = %s, ", addr->router->name); | |
1996 | fprintf(f, "transport = %s\n", (addr->transport == NULL)? US"unset" : | |
1997 | addr->transport->name); | |
1998 | ||
1999 | /* Show any hosts that are set up by a router unless the transport | |
2000 | is going to override them; fiddle a bit to get a nice format. */ | |
2001 | ||
2002 | if (addr->host_list != NULL && addr->transport != NULL && | |
2003 | !addr->transport->overrides_hosts) | |
2004 | { | |
2005 | host_item *h; | |
2006 | int maxlen = 0; | |
2007 | int maxaddlen = 0; | |
2008 | for (h = addr->host_list; h != NULL; h = h->next) | |
2009 | { | |
2010 | int len = Ustrlen(h->name); | |
2011 | if (len > maxlen) maxlen = len; | |
2012 | len = (h->address != NULL)? Ustrlen(h->address) : 7; | |
2013 | if (len > maxaddlen) maxaddlen = len; | |
2014 | } | |
2015 | for (h = addr->host_list; h != NULL; h = h->next) | |
2016 | { | |
2017 | int len = Ustrlen(h->name); | |
2018 | fprintf(f, " host %s ", h->name); | |
2019 | while (len++ < maxlen) fprintf(f, " "); | |
2020 | if (h->address != NULL) | |
2021 | { | |
2022 | fprintf(f, "[%s] ", h->address); | |
2023 | len = Ustrlen(h->address); | |
2024 | } | |
2025 | else if (!addr->transport->info->local) /* Omit [unknown] for local */ | |
2026 | { | |
2027 | fprintf(f, "[unknown] "); | |
2028 | len = 7; | |
2029 | } | |
2030 | else len = -3; | |
2031 | while (len++ < maxaddlen) fprintf(f," "); | |
2032 | if (h->mx >= 0) fprintf(f, "MX=%d", h->mx); | |
2033 | if (h->port != PORT_NONE) fprintf(f, " port=%d", h->port); | |
2034 | if (h->status == hstatus_unusable) fprintf(f, " ** unusable **"); | |
2035 | fprintf(f, "\n"); | |
2036 | } | |
2037 | } | |
2038 | } | |
2039 | } | |
2040 | ||
2041 | /* Yield will be DEFER or FAIL if any one address has, only for full_info (which is | |
2042 | the -bv or -bt case). */ | |
2043 | ||
2044 | out: | |
2045 | tls_modify_variables(&tls_in); | |
2046 | ||
2047 | return yield; | |
2048 | } | |
2049 | ||
2050 | ||
2051 | ||
2052 | ||
2053 | /************************************************* | |
2054 | * Check headers for syntax errors * | |
2055 | *************************************************/ | |
2056 | ||
2057 | /* This function checks those header lines that contain addresses, and verifies | |
2058 | that all the addresses therein are syntactially correct. | |
2059 | ||
2060 | Arguments: | |
2061 | msgptr where to put an error message | |
2062 | ||
2063 | Returns: OK | |
2064 | FAIL | |
2065 | */ | |
2066 | ||
2067 | int | |
2068 | verify_check_headers(uschar **msgptr) | |
2069 | { | |
2070 | header_line *h; | |
2071 | uschar *colon, *s; | |
2072 | int yield = OK; | |
2073 | ||
2074 | for (h = header_list; h != NULL && yield == OK; h = h->next) | |
2075 | { | |
2076 | if (h->type != htype_from && | |
2077 | h->type != htype_reply_to && | |
2078 | h->type != htype_sender && | |
2079 | h->type != htype_to && | |
2080 | h->type != htype_cc && | |
2081 | h->type != htype_bcc) | |
2082 | continue; | |
2083 | ||
2084 | colon = Ustrchr(h->text, ':'); | |
2085 | s = colon + 1; | |
2086 | while (isspace(*s)) s++; | |
2087 | ||
2088 | /* Loop for multiple addresses in the header, enabling group syntax. Note | |
2089 | that we have to reset this after the header has been scanned. */ | |
2090 | ||
2091 | parse_allow_group = TRUE; | |
2092 | ||
2093 | while (*s != 0) | |
2094 | { | |
2095 | uschar *ss = parse_find_address_end(s, FALSE); | |
2096 | uschar *recipient, *errmess; | |
2097 | int terminator = *ss; | |
2098 | int start, end, domain; | |
2099 | ||
2100 | /* Temporarily terminate the string at this point, and extract the | |
2101 | operative address within, allowing group syntax. */ | |
2102 | ||
2103 | *ss = 0; | |
2104 | recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE); | |
2105 | *ss = terminator; | |
2106 | ||
2107 | /* Permit an unqualified address only if the message is local, or if the | |
2108 | sending host is configured to be permitted to send them. */ | |
2109 | ||
2110 | if (recipient != NULL && domain == 0) | |
2111 | { | |
2112 | if (h->type == htype_from || h->type == htype_sender) | |
2113 | { | |
2114 | if (!allow_unqualified_sender) recipient = NULL; | |
2115 | } | |
2116 | else | |
2117 | { | |
2118 | if (!allow_unqualified_recipient) recipient = NULL; | |
2119 | } | |
2120 | if (recipient == NULL) errmess = US"unqualified address not permitted"; | |
2121 | } | |
2122 | ||
2123 | /* It's an error if no address could be extracted, except for the special | |
2124 | case of an empty address. */ | |
2125 | ||
2126 | if (recipient == NULL && Ustrcmp(errmess, "empty address") != 0) | |
2127 | { | |
2128 | uschar *verb = US"is"; | |
2129 | uschar *t = ss; | |
2130 | uschar *tt = colon; | |
2131 | int len; | |
2132 | ||
2133 | /* Arrange not to include any white space at the end in the | |
2134 | error message or the header name. */ | |
2135 | ||
2136 | while (t > s && isspace(t[-1])) t--; | |
2137 | while (tt > h->text && isspace(tt[-1])) tt--; | |
2138 | ||
2139 | /* Add the address that failed to the error message, since in a | |
2140 | header with very many addresses it is sometimes hard to spot | |
2141 | which one is at fault. However, limit the amount of address to | |
2142 | quote - cases have been seen where, for example, a missing double | |
2143 | quote in a humungous To: header creates an "address" that is longer | |
2144 | than string_sprintf can handle. */ | |
2145 | ||
2146 | len = t - s; | |
2147 | if (len > 1024) | |
2148 | { | |
2149 | len = 1024; | |
2150 | verb = US"begins"; | |
2151 | } | |
2152 | ||
2153 | *msgptr = string_printing( | |
2154 | string_sprintf("%s: failing address in \"%.*s:\" header %s: %.*s", | |
2155 | errmess, tt - h->text, h->text, verb, len, s)); | |
2156 | ||
2157 | yield = FAIL; | |
2158 | break; /* Out of address loop */ | |
2159 | } | |
2160 | ||
2161 | /* Advance to the next address */ | |
2162 | ||
2163 | s = ss + (terminator? 1:0); | |
2164 | while (isspace(*s)) s++; | |
2165 | } /* Next address */ | |
2166 | ||
2167 | parse_allow_group = FALSE; | |
2168 | parse_found_group = FALSE; | |
2169 | } /* Next header unless yield has been set FALSE */ | |
2170 | ||
2171 | return yield; | |
2172 | } | |
2173 | ||
2174 | ||
2175 | /************************************************* | |
2176 | * Check header names for 8-bit characters * | |
2177 | *************************************************/ | |
2178 | ||
2179 | /* This function checks for invalid charcters in header names. See | |
2180 | RFC 5322, 2.2. and RFC 6532, 3. | |
2181 | ||
2182 | Arguments: | |
2183 | msgptr where to put an error message | |
2184 | ||
2185 | Returns: OK | |
2186 | FAIL | |
2187 | */ | |
2188 | ||
2189 | int | |
2190 | verify_check_header_names_ascii(uschar **msgptr) | |
2191 | { | |
2192 | header_line *h; | |
2193 | uschar *colon, *s; | |
2194 | ||
2195 | for (h = header_list; h != NULL; h = h->next) | |
2196 | { | |
2197 | colon = Ustrchr(h->text, ':'); | |
2198 | for(s = h->text; s < colon; s++) | |
2199 | { | |
2200 | if ((*s < 33) || (*s > 126)) | |
2201 | { | |
2202 | *msgptr = string_sprintf("Invalid character in header \"%.*s\" found", | |
2203 | colon - h->text, h->text); | |
2204 | return FAIL; | |
2205 | } | |
2206 | } | |
2207 | } | |
2208 | return OK; | |
2209 | } | |
2210 | ||
2211 | /************************************************* | |
2212 | * Check for blind recipients * | |
2213 | *************************************************/ | |
2214 | ||
2215 | /* This function checks that every (envelope) recipient is mentioned in either | |
2216 | the To: or Cc: header lines, thus detecting blind carbon copies. | |
2217 | ||
2218 | There are two ways of scanning that could be used: either scan the header lines | |
2219 | and tick off the recipients, or scan the recipients and check the header lines. | |
2220 | The original proposed patch did the former, but I have chosen to do the latter, | |
2221 | because (a) it requires no memory and (b) will use fewer resources when there | |
2222 | are many addresses in To: and/or Cc: and only one or two envelope recipients. | |
2223 | ||
2224 | Arguments: none | |
2225 | Returns: OK if there are no blind recipients | |
2226 | FAIL if there is at least one blind recipient | |
2227 | */ | |
2228 | ||
2229 | int | |
2230 | verify_check_notblind(void) | |
2231 | { | |
2232 | int i; | |
2233 | for (i = 0; i < recipients_count; i++) | |
2234 | { | |
2235 | header_line *h; | |
2236 | BOOL found = FALSE; | |
2237 | uschar *address = recipients_list[i].address; | |
2238 | ||
2239 | for (h = header_list; !found && h != NULL; h = h->next) | |
2240 | { | |
2241 | uschar *colon, *s; | |
2242 | ||
2243 | if (h->type != htype_to && h->type != htype_cc) continue; | |
2244 | ||
2245 | colon = Ustrchr(h->text, ':'); | |
2246 | s = colon + 1; | |
2247 | while (isspace(*s)) s++; | |
2248 | ||
2249 | /* Loop for multiple addresses in the header, enabling group syntax. Note | |
2250 | that we have to reset this after the header has been scanned. */ | |
2251 | ||
2252 | parse_allow_group = TRUE; | |
2253 | ||
2254 | while (*s != 0) | |
2255 | { | |
2256 | uschar *ss = parse_find_address_end(s, FALSE); | |
2257 | uschar *recipient,*errmess; | |
2258 | int terminator = *ss; | |
2259 | int start, end, domain; | |
2260 | ||
2261 | /* Temporarily terminate the string at this point, and extract the | |
2262 | operative address within, allowing group syntax. */ | |
2263 | ||
2264 | *ss = 0; | |
2265 | recipient = parse_extract_address(s,&errmess,&start,&end,&domain,FALSE); | |
2266 | *ss = terminator; | |
2267 | ||
2268 | /* If we found a valid recipient that has a domain, compare it with the | |
2269 | envelope recipient. Local parts are compared case-sensitively, domains | |
2270 | case-insensitively. By comparing from the start with length "domain", we | |
2271 | include the "@" at the end, which ensures that we are comparing the whole | |
2272 | local part of each address. */ | |
2273 | ||
2274 | if (recipient != NULL && domain != 0) | |
2275 | { | |
2276 | found = Ustrncmp(recipient, address, domain) == 0 && | |
2277 | strcmpic(recipient + domain, address + domain) == 0; | |
2278 | if (found) break; | |
2279 | } | |
2280 | ||
2281 | /* Advance to the next address */ | |
2282 | ||
2283 | s = ss + (terminator? 1:0); | |
2284 | while (isspace(*s)) s++; | |
2285 | } /* Next address */ | |
2286 | ||
2287 | parse_allow_group = FALSE; | |
2288 | parse_found_group = FALSE; | |
2289 | } /* Next header (if found is false) */ | |
2290 | ||
2291 | if (!found) return FAIL; | |
2292 | } /* Next recipient */ | |
2293 | ||
2294 | return OK; | |
2295 | } | |
2296 | ||
2297 | ||
2298 | ||
2299 | /************************************************* | |
2300 | * Find if verified sender * | |
2301 | *************************************************/ | |
2302 | ||
2303 | /* Usually, just a single address is verified as the sender of the message. | |
2304 | However, Exim can be made to verify other addresses as well (often related in | |
2305 | some way), and this is useful in some environments. There may therefore be a | |
2306 | chain of such addresses that have previously been tested. This function finds | |
2307 | whether a given address is on the chain. | |
2308 | ||
2309 | Arguments: the address to be verified | |
2310 | Returns: pointer to an address item, or NULL | |
2311 | */ | |
2312 | ||
2313 | address_item * | |
2314 | verify_checked_sender(uschar *sender) | |
2315 | { | |
2316 | address_item *addr; | |
2317 | for (addr = sender_verified_list; addr != NULL; addr = addr->next) | |
2318 | if (Ustrcmp(sender, addr->address) == 0) break; | |
2319 | return addr; | |
2320 | } | |
2321 | ||
2322 | ||
2323 | ||
2324 | ||
2325 | ||
2326 | /************************************************* | |
2327 | * Get valid header address * | |
2328 | *************************************************/ | |
2329 | ||
2330 | /* Scan the originator headers of the message, looking for an address that | |
2331 | verifies successfully. RFC 822 says: | |
2332 | ||
2333 | o The "Sender" field mailbox should be sent notices of | |
2334 | any problems in transport or delivery of the original | |
2335 | messages. If there is no "Sender" field, then the | |
2336 | "From" field mailbox should be used. | |
2337 | ||
2338 | o If the "Reply-To" field exists, then the reply should | |
2339 | go to the addresses indicated in that field and not to | |
2340 | the address(es) indicated in the "From" field. | |
2341 | ||
2342 | So we check a Sender field if there is one, else a Reply_to field, else a From | |
2343 | field. As some strange messages may have more than one of these fields, | |
2344 | especially if they are resent- fields, check all of them if there is more than | |
2345 | one. | |
2346 | ||
2347 | Arguments: | |
2348 | user_msgptr points to where to put a user error message | |
2349 | log_msgptr points to where to put a log error message | |
2350 | callout timeout for callout check (passed to verify_address()) | |
2351 | callout_overall overall callout timeout (ditto) | |
2352 | callout_connect connect callout timeout (ditto) | |
2353 | se_mailfrom mailfrom for verify; NULL => "" | |
2354 | pm_mailfrom sender for pm callout check (passed to verify_address()) | |
2355 | options callout options (passed to verify_address()) | |
2356 | verrno where to put the address basic_errno | |
2357 | ||
2358 | If log_msgptr is set to something without setting user_msgptr, the caller | |
2359 | normally uses log_msgptr for both things. | |
2360 | ||
2361 | Returns: result of the verification attempt: OK, FAIL, or DEFER; | |
2362 | FAIL is given if no appropriate headers are found | |
2363 | */ | |
2364 | ||
2365 | int | |
2366 | verify_check_header_address(uschar **user_msgptr, uschar **log_msgptr, | |
2367 | int callout, int callout_overall, int callout_connect, uschar *se_mailfrom, | |
2368 | uschar *pm_mailfrom, int options, int *verrno) | |
2369 | { | |
2370 | static int header_types[] = { htype_sender, htype_reply_to, htype_from }; | |
2371 | BOOL done = FALSE; | |
2372 | int yield = FAIL; | |
2373 | int i; | |
2374 | ||
2375 | for (i = 0; i < 3 && !done; i++) | |
2376 | { | |
2377 | header_line *h; | |
2378 | for (h = header_list; h != NULL && !done; h = h->next) | |
2379 | { | |
2380 | int terminator, new_ok; | |
2381 | uschar *s, *ss, *endname; | |
2382 | ||
2383 | if (h->type != header_types[i]) continue; | |
2384 | s = endname = Ustrchr(h->text, ':') + 1; | |
2385 | ||
2386 | /* Scan the addresses in the header, enabling group syntax. Note that we | |
2387 | have to reset this after the header has been scanned. */ | |
2388 | ||
2389 | parse_allow_group = TRUE; | |
2390 | ||
2391 | while (*s != 0) | |
2392 | { | |
2393 | address_item *vaddr; | |
2394 | ||
2395 | while (isspace(*s) || *s == ',') s++; | |
2396 | if (*s == 0) break; /* End of header */ | |
2397 | ||
2398 | ss = parse_find_address_end(s, FALSE); | |
2399 | ||
2400 | /* The terminator is a comma or end of header, but there may be white | |
2401 | space preceding it (including newline for the last address). Move back | |
2402 | past any white space so we can check against any cached envelope sender | |
2403 | address verifications. */ | |
2404 | ||
2405 | while (isspace(ss[-1])) ss--; | |
2406 | terminator = *ss; | |
2407 | *ss = 0; | |
2408 | ||
2409 | HDEBUG(D_verify) debug_printf("verifying %.*s header address %s\n", | |
2410 | (int)(endname - h->text), h->text, s); | |
2411 | ||
2412 | /* See if we have already verified this address as an envelope sender, | |
2413 | and if so, use the previous answer. */ | |
2414 | ||
2415 | vaddr = verify_checked_sender(s); | |
2416 | ||
2417 | if (vaddr != NULL && /* Previously checked */ | |
2418 | (callout <= 0 || /* No callout needed; OR */ | |
2419 | vaddr->special_action > 256)) /* Callout was done */ | |
2420 | { | |
2421 | new_ok = vaddr->special_action & 255; | |
2422 | HDEBUG(D_verify) debug_printf("previously checked as envelope sender\n"); | |
2423 | *ss = terminator; /* Restore shortened string */ | |
2424 | } | |
2425 | ||
2426 | /* Otherwise we run the verification now. We must restore the shortened | |
2427 | string before running the verification, so the headers are correct, in | |
2428 | case there is any rewriting. */ | |
2429 | ||
2430 | else | |
2431 | { | |
2432 | int start, end, domain; | |
2433 | uschar *address = parse_extract_address(s, log_msgptr, &start, &end, | |
2434 | &domain, FALSE); | |
2435 | ||
2436 | *ss = terminator; | |
2437 | ||
2438 | /* If we found an empty address, just carry on with the next one, but | |
2439 | kill the message. */ | |
2440 | ||
2441 | if (address == NULL && Ustrcmp(*log_msgptr, "empty address") == 0) | |
2442 | { | |
2443 | *log_msgptr = NULL; | |
2444 | s = ss; | |
2445 | continue; | |
2446 | } | |
2447 | ||
2448 | /* If verification failed because of a syntax error, fail this | |
2449 | function, and ensure that the failing address gets added to the error | |
2450 | message. */ | |
2451 | ||
2452 | if (address == NULL) | |
2453 | { | |
2454 | new_ok = FAIL; | |
2455 | while (ss > s && isspace(ss[-1])) ss--; | |
2456 | *log_msgptr = string_sprintf("syntax error in '%.*s' header when " | |
2457 | "scanning for sender: %s in \"%.*s\"", | |
2458 | endname - h->text, h->text, *log_msgptr, ss - s, s); | |
2459 | yield = FAIL; | |
2460 | done = TRUE; | |
2461 | break; | |
2462 | } | |
2463 | ||
2464 | /* Else go ahead with the sender verification. But it isn't *the* | |
2465 | sender of the message, so set vopt_fake_sender to stop sender_address | |
2466 | being replaced after rewriting or qualification. */ | |
2467 | ||
2468 | else | |
2469 | { | |
2470 | vaddr = deliver_make_addr(address, FALSE); | |
2471 | new_ok = verify_address(vaddr, NULL, options | vopt_fake_sender, | |
2472 | callout, callout_overall, callout_connect, se_mailfrom, | |
2473 | pm_mailfrom, NULL); | |
2474 | } | |
2475 | } | |
2476 | ||
2477 | /* We now have the result, either newly found, or cached. If we are | |
2478 | giving out error details, set a specific user error. This means that the | |
2479 | last of these will be returned to the user if all three fail. We do not | |
2480 | set a log message - the generic one below will be used. */ | |
2481 | ||
2482 | if (new_ok != OK) | |
2483 | { | |
2484 | *verrno = vaddr->basic_errno; | |
2485 | if (smtp_return_error_details) | |
2486 | { | |
2487 | *user_msgptr = string_sprintf("Rejected after DATA: " | |
2488 | "could not verify \"%.*s\" header address\n%s: %s", | |
2489 | endname - h->text, h->text, vaddr->address, vaddr->message); | |
2490 | } | |
2491 | } | |
2492 | ||
2493 | /* Success or defer */ | |
2494 | ||
2495 | if (new_ok == OK) | |
2496 | { | |
2497 | yield = OK; | |
2498 | done = TRUE; | |
2499 | break; | |
2500 | } | |
2501 | ||
2502 | if (new_ok == DEFER) yield = DEFER; | |
2503 | ||
2504 | /* Move on to any more addresses in the header */ | |
2505 | ||
2506 | s = ss; | |
2507 | } /* Next address */ | |
2508 | ||
2509 | parse_allow_group = FALSE; | |
2510 | parse_found_group = FALSE; | |
2511 | } /* Next header, unless done */ | |
2512 | } /* Next header type unless done */ | |
2513 | ||
2514 | if (yield == FAIL && *log_msgptr == NULL) | |
2515 | *log_msgptr = US"there is no valid sender in any header line"; | |
2516 | ||
2517 | if (yield == DEFER && *log_msgptr == NULL) | |
2518 | *log_msgptr = US"all attempts to verify a sender in a header line deferred"; | |
2519 | ||
2520 | return yield; | |
2521 | } | |
2522 | ||
2523 | ||
2524 | ||
2525 | ||
2526 | /************************************************* | |
2527 | * Get RFC 1413 identification * | |
2528 | *************************************************/ | |
2529 | ||
2530 | /* Attempt to get an id from the sending machine via the RFC 1413 protocol. If | |
2531 | the timeout is set to zero, then the query is not done. There may also be lists | |
2532 | of hosts and nets which are exempt. To guard against malefactors sending | |
2533 | non-printing characters which could, for example, disrupt a message's headers, | |
2534 | make sure the string consists of printing characters only. | |
2535 | ||
2536 | Argument: | |
2537 | port the port to connect to; usually this is IDENT_PORT (113), but when | |
2538 | running in the test harness with -bh a different value is used. | |
2539 | ||
2540 | Returns: nothing | |
2541 | ||
2542 | Side effect: any received ident value is put in sender_ident (NULL otherwise) | |
2543 | */ | |
2544 | ||
2545 | void | |
2546 | verify_get_ident(int port) | |
2547 | { | |
2548 | int sock, host_af, qlen; | |
2549 | int received_sender_port, received_interface_port, n; | |
2550 | uschar *p; | |
2551 | uschar buffer[2048]; | |
2552 | ||
2553 | /* Default is no ident. Check whether we want to do an ident check for this | |
2554 | host. */ | |
2555 | ||
2556 | sender_ident = NULL; | |
2557 | if (rfc1413_query_timeout <= 0 || verify_check_host(&rfc1413_hosts) != OK) | |
2558 | return; | |
2559 | ||
2560 | DEBUG(D_ident) debug_printf("doing ident callback\n"); | |
2561 | ||
2562 | /* Set up a connection to the ident port of the remote host. Bind the local end | |
2563 | to the incoming interface address. If the sender host address is an IPv6 | |
2564 | address, the incoming interface address will also be IPv6. */ | |
2565 | ||
2566 | host_af = (Ustrchr(sender_host_address, ':') == NULL)? AF_INET : AF_INET6; | |
2567 | sock = ip_socket(SOCK_STREAM, host_af); | |
2568 | if (sock < 0) return; | |
2569 | ||
2570 | if (ip_bind(sock, host_af, interface_address, 0) < 0) | |
2571 | { | |
2572 | DEBUG(D_ident) debug_printf("bind socket for ident failed: %s\n", | |
2573 | strerror(errno)); | |
2574 | goto END_OFF; | |
2575 | } | |
2576 | ||
2577 | if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout) | |
2578 | < 0) | |
2579 | { | |
2580 | if (errno == ETIMEDOUT && (log_extra_selector & LX_ident_timeout) != 0) | |
2581 | { | |
2582 | log_write(0, LOG_MAIN, "ident connection to %s timed out", | |
2583 | sender_host_address); | |
2584 | } | |
2585 | else | |
2586 | { | |
2587 | DEBUG(D_ident) debug_printf("ident connection to %s failed: %s\n", | |
2588 | sender_host_address, strerror(errno)); | |
2589 | } | |
2590 | goto END_OFF; | |
2591 | } | |
2592 | ||
2593 | /* Construct and send the query. */ | |
2594 | ||
2595 | sprintf(CS buffer, "%d , %d\r\n", sender_host_port, interface_port); | |
2596 | qlen = Ustrlen(buffer); | |
2597 | if (send(sock, buffer, qlen, 0) < 0) | |
2598 | { | |
2599 | DEBUG(D_ident) debug_printf("ident send failed: %s\n", strerror(errno)); | |
2600 | goto END_OFF; | |
2601 | } | |
2602 | ||
2603 | /* Read a response line. We put it into the rest of the buffer, using several | |
2604 | recv() calls if necessary. */ | |
2605 | ||
2606 | p = buffer + qlen; | |
2607 | ||
2608 | for (;;) | |
2609 | { | |
2610 | uschar *pp; | |
2611 | int count; | |
2612 | int size = sizeof(buffer) - (p - buffer); | |
2613 | ||
2614 | if (size <= 0) goto END_OFF; /* Buffer filled without seeing \n. */ | |
2615 | count = ip_recv(sock, p, size, rfc1413_query_timeout); | |
2616 | if (count <= 0) goto END_OFF; /* Read error or EOF */ | |
2617 | ||
2618 | /* Scan what we just read, to see if we have reached the terminating \r\n. Be | |
2619 | generous, and accept a plain \n terminator as well. The only illegal | |
2620 | character is 0. */ | |
2621 | ||
2622 | for (pp = p; pp < p + count; pp++) | |
2623 | { | |
2624 | if (*pp == 0) goto END_OFF; /* Zero octet not allowed */ | |
2625 | if (*pp == '\n') | |
2626 | { | |
2627 | if (pp[-1] == '\r') pp--; | |
2628 | *pp = 0; | |
2629 | goto GOT_DATA; /* Break out of both loops */ | |
2630 | } | |
2631 | } | |
2632 | ||
2633 | /* Reached the end of the data without finding \n. Let the loop continue to | |
2634 | read some more, if there is room. */ | |
2635 | ||
2636 | p = pp; | |
2637 | } | |
2638 | ||
2639 | GOT_DATA: | |
2640 | ||
2641 | /* We have received a line of data. Check it carefully. It must start with the | |
2642 | same two port numbers that we sent, followed by data as defined by the RFC. For | |
2643 | example, | |
2644 | ||
2645 | 12345 , 25 : USERID : UNIX :root | |
2646 | ||
2647 | However, the amount of white space may be different to what we sent. In the | |
2648 | "osname" field there may be several sub-fields, comma separated. The data we | |
2649 | actually want to save follows the third colon. Some systems put leading spaces | |
2650 | in it - we discard those. */ | |
2651 | ||
2652 | if (sscanf(CS buffer + qlen, "%d , %d%n", &received_sender_port, | |
2653 | &received_interface_port, &n) != 2 || | |
2654 | received_sender_port != sender_host_port || | |
2655 | received_interface_port != interface_port) | |
2656 | goto END_OFF; | |
2657 | ||
2658 | p = buffer + qlen + n; | |
2659 | while(isspace(*p)) p++; | |
2660 | if (*p++ != ':') goto END_OFF; | |
2661 | while(isspace(*p)) p++; | |
2662 | if (Ustrncmp(p, "USERID", 6) != 0) goto END_OFF; | |
2663 | p += 6; | |
2664 | while(isspace(*p)) p++; | |
2665 | if (*p++ != ':') goto END_OFF; | |
2666 | while (*p != 0 && *p != ':') p++; | |
2667 | if (*p++ == 0) goto END_OFF; | |
2668 | while(isspace(*p)) p++; | |
2669 | if (*p == 0) goto END_OFF; | |
2670 | ||
2671 | /* The rest of the line is the data we want. We turn it into printing | |
2672 | characters when we save it, so that it cannot mess up the format of any logging | |
2673 | or Received: lines into which it gets inserted. We keep a maximum of 127 | |
2674 | characters. */ | |
2675 | ||
2676 | sender_ident = string_printing(string_copyn(p, 127)); | |
2677 | DEBUG(D_ident) debug_printf("sender_ident = %s\n", sender_ident); | |
2678 | ||
2679 | END_OFF: | |
2680 | (void)close(sock); | |
2681 | return; | |
2682 | } | |
2683 | ||
2684 | ||
2685 | ||
2686 | ||
2687 | /************************************************* | |
2688 | * Match host to a single host-list item * | |
2689 | *************************************************/ | |
2690 | ||
2691 | /* This function compares a host (name or address) against a single item | |
2692 | from a host list. The host name gets looked up if it is needed and is not | |
2693 | already known. The function is called from verify_check_this_host() via | |
2694 | match_check_list(), which is why most of its arguments are in a single block. | |
2695 | ||
2696 | Arguments: | |
2697 | arg the argument block (see below) | |
2698 | ss the host-list item | |
2699 | valueptr where to pass back looked up data, or NULL | |
2700 | error for error message when returning ERROR | |
2701 | ||
2702 | The block contains: | |
2703 | host_name (a) the host name, or | |
2704 | (b) NULL, implying use sender_host_name and | |
2705 | sender_host_aliases, looking them up if required, or | |
2706 | (c) the empty string, meaning that only IP address matches | |
2707 | are permitted | |
2708 | host_address the host address | |
2709 | host_ipv4 the IPv4 address taken from an IPv6 one | |
2710 | ||
2711 | Returns: OK matched | |
2712 | FAIL did not match | |
2713 | DEFER lookup deferred | |
2714 | ERROR (a) failed to find the host name or IP address, or | |
2715 | (b) unknown lookup type specified, or | |
2716 | (c) host name encountered when only IP addresses are | |
2717 | being matched | |
2718 | */ | |
2719 | ||
2720 | int | |
2721 | check_host(void *arg, uschar *ss, uschar **valueptr, uschar **error) | |
2722 | { | |
2723 | check_host_block *cb = (check_host_block *)arg; | |
2724 | int mlen = -1; | |
2725 | int maskoffset; | |
2726 | BOOL iplookup = FALSE; | |
2727 | BOOL isquery = FALSE; | |
2728 | BOOL isiponly = cb->host_name != NULL && cb->host_name[0] == 0; | |
2729 | uschar *t; | |
2730 | uschar *semicolon; | |
2731 | uschar **aliases; | |
2732 | ||
2733 | /* Optimize for the special case when the pattern is "*". */ | |
2734 | ||
2735 | if (*ss == '*' && ss[1] == 0) return OK; | |
2736 | ||
2737 | /* If the pattern is empty, it matches only in the case when there is no host - | |
2738 | this can occur in ACL checking for SMTP input using the -bs option. In this | |
2739 | situation, the host address is the empty string. */ | |
2740 | ||
2741 | if (cb->host_address[0] == 0) return (*ss == 0)? OK : FAIL; | |
2742 | if (*ss == 0) return FAIL; | |
2743 | ||
2744 | /* If the pattern is precisely "@" then match against the primary host name, | |
2745 | provided that host name matching is permitted; if it's "@[]" match against the | |
2746 | local host's IP addresses. */ | |
2747 | ||
2748 | if (*ss == '@') | |
2749 | { | |
2750 | if (ss[1] == 0) | |
2751 | { | |
2752 | if (isiponly) return ERROR; | |
2753 | ss = primary_hostname; | |
2754 | } | |
2755 | else if (Ustrcmp(ss, "@[]") == 0) | |
2756 | { | |
2757 | ip_address_item *ip; | |
2758 | for (ip = host_find_interfaces(); ip != NULL; ip = ip->next) | |
2759 | if (Ustrcmp(ip->address, cb->host_address) == 0) return OK; | |
2760 | return FAIL; | |
2761 | } | |
2762 | } | |
2763 | ||
2764 | /* If the pattern is an IP address, optionally followed by a bitmask count, do | |
2765 | a (possibly masked) comparision with the current IP address. */ | |
2766 | ||
2767 | if (string_is_ip_address(ss, &maskoffset) != 0) | |
2768 | return (host_is_in_net(cb->host_address, ss, maskoffset)? OK : FAIL); | |
2769 | ||
2770 | /* The pattern is not an IP address. A common error that people make is to omit | |
2771 | one component of an IPv4 address, either by accident, or believing that, for | |
2772 | example, 1.2.3/24 is the same as 1.2.3.0/24, or 1.2.3 is the same as 1.2.3.0, | |
2773 | which it isn't. (Those applications that do accept 1.2.3 as an IP address | |
2774 | interpret it as 1.2.0.3 because the final component becomes 16-bit - this is an | |
2775 | ancient specification.) To aid in debugging these cases, we give a specific | |
2776 | error if the pattern contains only digits and dots or contains a slash preceded | |
2777 | only by digits and dots (a slash at the start indicates a file name and of | |
2778 | course slashes may be present in lookups, but not preceded only by digits and | |
2779 | dots). */ | |
2780 | ||
2781 | for (t = ss; isdigit(*t) || *t == '.'; t++); | |
2782 | if (*t == 0 || (*t == '/' && t != ss)) | |
2783 | { | |
2784 | *error = US"malformed IPv4 address or address mask"; | |
2785 | return ERROR; | |
2786 | } | |
2787 | ||
2788 | /* See if there is a semicolon in the pattern */ | |
2789 | ||
2790 | semicolon = Ustrchr(ss, ';'); | |
2791 | ||
2792 | /* If we are doing an IP address only match, then all lookups must be IP | |
2793 | address lookups, even if there is no "net-". */ | |
2794 | ||
2795 | if (isiponly) | |
2796 | { | |
2797 | iplookup = semicolon != NULL; | |
2798 | } | |
2799 | ||
2800 | /* Otherwise, if the item is of the form net[n]-lookup;<file|query> then it is | |
2801 | a lookup on a masked IP network, in textual form. We obey this code even if we | |
2802 | have already set iplookup, so as to skip over the "net-" prefix and to set the | |
2803 | mask length. The net- stuff really only applies to single-key lookups where the | |
2804 | key is implicit. For query-style lookups the key is specified in the query. | |
2805 | From release 4.30, the use of net- for query style is no longer needed, but we | |
2806 | retain it for backward compatibility. */ | |
2807 | ||
2808 | if (Ustrncmp(ss, "net", 3) == 0 && semicolon != NULL) | |
2809 | { | |
2810 | mlen = 0; | |
2811 | for (t = ss + 3; isdigit(*t); t++) mlen = mlen * 10 + *t - '0'; | |
2812 | if (mlen == 0 && t == ss+3) mlen = -1; /* No mask supplied */ | |
2813 | iplookup = (*t++ == '-'); | |
2814 | } | |
2815 | else t = ss; | |
2816 | ||
2817 | /* Do the IP address lookup if that is indeed what we have */ | |
2818 | ||
2819 | if (iplookup) | |
2820 | { | |
2821 | int insize; | |
2822 | int search_type; | |
2823 | int incoming[4]; | |
2824 | void *handle; | |
2825 | uschar *filename, *key, *result; | |
2826 | uschar buffer[64]; | |
2827 | ||
2828 | /* Find the search type */ | |
2829 | ||
2830 | search_type = search_findtype(t, semicolon - t); | |
2831 | ||
2832 | if (search_type < 0) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", | |
2833 | search_error_message); | |
2834 | ||
2835 | /* Adjust parameters for the type of lookup. For a query-style lookup, there | |
2836 | is no file name, and the "key" is just the query. For query-style with a file | |
2837 | name, we have to fish the file off the start of the query. For a single-key | |
2838 | lookup, the key is the current IP address, masked appropriately, and | |
2839 | reconverted to text form, with the mask appended. For IPv6 addresses, specify | |
2840 | dot separators instead of colons, except when the lookup type is "iplsearch". | |
2841 | */ | |
2842 | ||
2843 | if (mac_islookup(search_type, lookup_absfilequery)) | |
2844 | { | |
2845 | filename = semicolon + 1; | |
2846 | key = filename; | |
2847 | while (*key != 0 && !isspace(*key)) key++; | |
2848 | filename = string_copyn(filename, key - filename); | |
2849 | while (isspace(*key)) key++; | |
2850 | } | |
2851 | else if (mac_islookup(search_type, lookup_querystyle)) | |
2852 | { | |
2853 | filename = NULL; | |
2854 | key = semicolon + 1; | |
2855 | } | |
2856 | else /* Single-key style */ | |
2857 | { | |
2858 | int sep = (Ustrcmp(lookup_list[search_type]->name, "iplsearch") == 0)? | |
2859 | ':' : '.'; | |
2860 | insize = host_aton(cb->host_address, incoming); | |
2861 | host_mask(insize, incoming, mlen); | |
2862 | (void)host_nmtoa(insize, incoming, mlen, buffer, sep); | |
2863 | key = buffer; | |
2864 | filename = semicolon + 1; | |
2865 | } | |
2866 | ||
2867 | /* Now do the actual lookup; note that there is no search_close() because | |
2868 | of the caching arrangements. */ | |
2869 | ||
2870 | handle = search_open(filename, search_type, 0, NULL, NULL); | |
2871 | if (handle == NULL) log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s", | |
2872 | search_error_message); | |
2873 | result = search_find(handle, filename, key, -1, NULL, 0, 0, NULL); | |
2874 | if (valueptr != NULL) *valueptr = result; | |
2875 | return (result != NULL)? OK : search_find_defer? DEFER: FAIL; | |
2876 | } | |
2877 | ||
2878 | /* The pattern is not an IP address or network reference of any kind. That is, | |
2879 | it is a host name pattern. If this is an IP only match, there's an error in the | |
2880 | host list. */ | |
2881 | ||
2882 | if (isiponly) | |
2883 | { | |
2884 | *error = US"cannot match host name in match_ip list"; | |
2885 | return ERROR; | |
2886 | } | |
2887 | ||
2888 | /* Check the characters of the pattern to see if they comprise only letters, | |
2889 | digits, full stops, and hyphens (the constituents of domain names). Allow | |
2890 | underscores, as they are all too commonly found. Sigh. Also, if | |
2891 | allow_utf8_domains is set, allow top-bit characters. */ | |
2892 | ||
2893 | for (t = ss; *t != 0; t++) | |
2894 | if (!isalnum(*t) && *t != '.' && *t != '-' && *t != '_' && | |
2895 | (!allow_utf8_domains || *t < 128)) break; | |
2896 | ||
2897 | /* If the pattern is a complete domain name, with no fancy characters, look up | |
2898 | its IP address and match against that. Note that a multi-homed host will add | |
2899 | items to the chain. */ | |
2900 | ||
2901 | if (*t == 0) | |
2902 | { | |
2903 | int rc; | |
2904 | host_item h; | |
2905 | h.next = NULL; | |
2906 | h.name = ss; | |
2907 | h.address = NULL; | |
2908 | h.mx = MX_NONE; | |
2909 | ||
2910 | rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE); | |
2911 | if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL) | |
2912 | { | |
2913 | host_item *hh; | |
2914 | for (hh = &h; hh != NULL; hh = hh->next) | |
2915 | { | |
2916 | if (host_is_in_net(hh->address, cb->host_address, 0)) return OK; | |
2917 | } | |
2918 | return FAIL; | |
2919 | } | |
2920 | if (rc == HOST_FIND_AGAIN) return DEFER; | |
2921 | *error = string_sprintf("failed to find IP address for %s", ss); | |
2922 | return ERROR; | |
2923 | } | |
2924 | ||
2925 | /* Almost all subsequent comparisons require the host name, and can be done | |
2926 | using the general string matching function. When this function is called for | |
2927 | outgoing hosts, the name is always given explicitly. If it is NULL, it means we | |
2928 | must use sender_host_name and its aliases, looking them up if necessary. */ | |
2929 | ||
2930 | if (cb->host_name != NULL) /* Explicit host name given */ | |
2931 | return match_check_string(cb->host_name, ss, -1, TRUE, TRUE, TRUE, | |
2932 | valueptr); | |
2933 | ||
2934 | /* Host name not given; in principle we need the sender host name and its | |
2935 | aliases. However, for query-style lookups, we do not need the name if the | |
2936 | query does not contain $sender_host_name. From release 4.23, a reference to | |
2937 | $sender_host_name causes it to be looked up, so we don't need to do the lookup | |
2938 | on spec. */ | |
2939 | ||
2940 | if ((semicolon = Ustrchr(ss, ';')) != NULL) | |
2941 | { | |
2942 | uschar *affix; | |
2943 | int partial, affixlen, starflags, id; | |
2944 | ||
2945 | *semicolon = 0; | |
2946 | id = search_findtype_partial(ss, &partial, &affix, &affixlen, &starflags); | |
2947 | *semicolon=';'; | |
2948 | ||
2949 | if (id < 0) /* Unknown lookup type */ | |
2950 | { | |
2951 | log_write(0, LOG_MAIN|LOG_PANIC, "%s in host list item \"%s\"", | |
2952 | search_error_message, ss); | |
2953 | return DEFER; | |
2954 | } | |
2955 | isquery = mac_islookup(id, lookup_querystyle|lookup_absfilequery); | |
2956 | } | |
2957 | ||
2958 | if (isquery) | |
2959 | { | |
2960 | switch(match_check_string(US"", ss, -1, TRUE, TRUE, TRUE, valueptr)) | |
2961 | { | |
2962 | case OK: return OK; | |
2963 | case DEFER: return DEFER; | |
2964 | default: return FAIL; | |
2965 | } | |
2966 | } | |
2967 | ||
2968 | /* Not a query-style lookup; must ensure the host name is present, and then we | |
2969 | do a check on the name and all its aliases. */ | |
2970 | ||
2971 | if (sender_host_name == NULL) | |
2972 | { | |
2973 | HDEBUG(D_host_lookup) | |
2974 | debug_printf("sender host name required, to match against %s\n", ss); | |
2975 | if (host_lookup_failed || host_name_lookup() != OK) | |
2976 | { | |
2977 | *error = string_sprintf("failed to find host name for %s", | |
2978 | sender_host_address);; | |
2979 | return ERROR; | |
2980 | } | |
2981 | host_build_sender_fullhost(); | |
2982 | } | |
2983 | ||
2984 | /* Match on the sender host name, using the general matching function */ | |
2985 | ||
2986 | switch(match_check_string(sender_host_name, ss, -1, TRUE, TRUE, TRUE, | |
2987 | valueptr)) | |
2988 | { | |
2989 | case OK: return OK; | |
2990 | case DEFER: return DEFER; | |
2991 | } | |
2992 | ||
2993 | /* If there are aliases, try matching on them. */ | |
2994 | ||
2995 | aliases = sender_host_aliases; | |
2996 | while (*aliases != NULL) | |
2997 | { | |
2998 | switch(match_check_string(*aliases++, ss, -1, TRUE, TRUE, TRUE, valueptr)) | |
2999 | { | |
3000 | case OK: return OK; | |
3001 | case DEFER: return DEFER; | |
3002 | } | |
3003 | } | |
3004 | return FAIL; | |
3005 | } | |
3006 | ||
3007 | ||
3008 | ||
3009 | ||
3010 | /************************************************* | |
3011 | * Check a specific host matches a host list * | |
3012 | *************************************************/ | |
3013 | ||
3014 | /* This function is passed a host list containing items in a number of | |
3015 | different formats and the identity of a host. Its job is to determine whether | |
3016 | the given host is in the set of hosts defined by the list. The host name is | |
3017 | passed as a pointer so that it can be looked up if needed and not already | |
3018 | known. This is commonly the case when called from verify_check_host() to check | |
3019 | an incoming connection. When called from elsewhere the host name should usually | |
3020 | be set. | |
3021 | ||
3022 | This function is now just a front end to match_check_list(), which runs common | |
3023 | code for scanning a list. We pass it the check_host() function to perform a | |
3024 | single test. | |
3025 | ||
3026 | Arguments: | |
3027 | listptr pointer to the host list | |
3028 | cache_bits pointer to cache for named lists, or NULL | |
3029 | host_name the host name or NULL, implying use sender_host_name and | |
3030 | sender_host_aliases, looking them up if required | |
3031 | host_address the IP address | |
3032 | valueptr if not NULL, data from a lookup is passed back here | |
3033 | ||
3034 | Returns: OK if the host is in the defined set | |
3035 | FAIL if the host is not in the defined set, | |
3036 | DEFER if a data lookup deferred (not a host lookup) | |
3037 | ||
3038 | If the host name was needed in order to make a comparison, and could not be | |
3039 | determined from the IP address, the result is FAIL unless the item | |
3040 | "+allow_unknown" was met earlier in the list, in which case OK is returned. */ | |
3041 | ||
3042 | int | |
3043 | verify_check_this_host(uschar **listptr, unsigned int *cache_bits, | |
3044 | uschar *host_name, uschar *host_address, uschar **valueptr) | |
3045 | { | |
3046 | int rc; | |
3047 | unsigned int *local_cache_bits = cache_bits; | |
3048 | uschar *save_host_address = deliver_host_address; | |
3049 | check_host_block cb; | |
3050 | cb.host_name = host_name; | |
3051 | cb.host_address = host_address; | |
3052 | ||
3053 | if (valueptr != NULL) *valueptr = NULL; | |
3054 | ||
3055 | /* If the host address starts off ::ffff: it is an IPv6 address in | |
3056 | IPv4-compatible mode. Find the IPv4 part for checking against IPv4 | |
3057 | addresses. */ | |
3058 | ||
3059 | cb.host_ipv4 = (Ustrncmp(host_address, "::ffff:", 7) == 0)? | |
3060 | host_address + 7 : host_address; | |
3061 | ||
3062 | /* During the running of the check, put the IP address into $host_address. In | |
3063 | the case of calls from the smtp transport, it will already be there. However, | |
3064 | in other calls (e.g. when testing ignore_target_hosts), it won't. Just to be on | |
3065 | the safe side, any existing setting is preserved, though as I write this | |
3066 | (November 2004) I can't see any cases where it is actually needed. */ | |
3067 | ||
3068 | deliver_host_address = host_address; | |
3069 | rc = match_check_list( | |
3070 | listptr, /* the list */ | |
3071 | 0, /* separator character */ | |
3072 | &hostlist_anchor, /* anchor pointer */ | |
3073 | &local_cache_bits, /* cache pointer */ | |
3074 | check_host, /* function for testing */ | |
3075 | &cb, /* argument for function */ | |
3076 | MCL_HOST, /* type of check */ | |
3077 | (host_address == sender_host_address)? | |
3078 | US"host" : host_address, /* text for debugging */ | |
3079 | valueptr); /* where to pass back data */ | |
3080 | deliver_host_address = save_host_address; | |
3081 | return rc; | |
3082 | } | |
3083 | ||
3084 | ||
3085 | ||
3086 | ||
3087 | /************************************************* | |
3088 | * Check the remote host matches a list * | |
3089 | *************************************************/ | |
3090 | ||
3091 | /* This is a front end to verify_check_this_host(), created because checking | |
3092 | the remote host is a common occurrence. With luck, a good compiler will spot | |
3093 | the tail recursion and optimize it. If there's no host address, this is | |
3094 | command-line SMTP input - check against an empty string for the address. | |
3095 | ||
3096 | Arguments: | |
3097 | listptr pointer to the host list | |
3098 | ||
3099 | Returns: the yield of verify_check_this_host(), | |
3100 | i.e. OK, FAIL, or DEFER | |
3101 | */ | |
3102 | ||
3103 | int | |
3104 | verify_check_host(uschar **listptr) | |
3105 | { | |
3106 | return verify_check_this_host(listptr, sender_host_cache, NULL, | |
3107 | (sender_host_address == NULL)? US"" : sender_host_address, NULL); | |
3108 | } | |
3109 | ||
3110 | ||
3111 | ||
3112 | ||
3113 | ||
3114 | /************************************************* | |
3115 | * Invert an IP address * | |
3116 | *************************************************/ | |
3117 | ||
3118 | /* Originally just used for DNS xBL lists, now also used for the | |
3119 | reverse_ip expansion operator. | |
3120 | ||
3121 | Arguments: | |
3122 | buffer where to put the answer | |
3123 | address the address to invert | |
3124 | */ | |
3125 | ||
3126 | void | |
3127 | invert_address(uschar *buffer, uschar *address) | |
3128 | { | |
3129 | int bin[4]; | |
3130 | uschar *bptr = buffer; | |
3131 | ||
3132 | /* If this is an IPv4 address mapped into IPv6 format, adjust the pointer | |
3133 | to the IPv4 part only. */ | |
3134 | ||
3135 | if (Ustrncmp(address, "::ffff:", 7) == 0) address += 7; | |
3136 | ||
3137 | /* Handle IPv4 address: when HAVE_IPV6 is false, the result of host_aton() is | |
3138 | always 1. */ | |
3139 | ||
3140 | if (host_aton(address, bin) == 1) | |
3141 | { | |
3142 | int i; | |
3143 | int x = bin[0]; | |
3144 | for (i = 0; i < 4; i++) | |
3145 | { | |
3146 | sprintf(CS bptr, "%d.", x & 255); | |
3147 | while (*bptr) bptr++; | |
3148 | x >>= 8; | |
3149 | } | |
3150 | } | |
3151 | ||
3152 | /* Handle IPv6 address. Actually, as far as I know, there are no IPv6 addresses | |
3153 | in any DNS black lists, and the format in which they will be looked up is | |
3154 | unknown. This is just a guess. */ | |
3155 | ||
3156 | #if HAVE_IPV6 | |
3157 | else | |
3158 | { | |
3159 | int i, j; | |
3160 | for (j = 3; j >= 0; j--) | |
3161 | { | |
3162 | int x = bin[j]; | |
3163 | for (i = 0; i < 8; i++) | |
3164 | { | |
3165 | sprintf(CS bptr, "%x.", x & 15); | |
3166 | while (*bptr) bptr++; | |
3167 | x >>= 4; | |
3168 | } | |
3169 | } | |
3170 | } | |
3171 | #endif | |
3172 | ||
3173 | /* Remove trailing period -- this is needed so that both arbitrary | |
3174 | dnsbl keydomains and inverted addresses may be combined with the | |
3175 | same format string, "%s.%s" */ | |
3176 | ||
3177 | *(--bptr) = 0; | |
3178 | } | |
3179 | ||
3180 | ||
3181 | ||
3182 | /************************************************* | |
3183 | * Perform a single dnsbl lookup * | |
3184 | *************************************************/ | |
3185 | ||
3186 | /* This function is called from verify_check_dnsbl() below. It is also called | |
3187 | recursively from within itself when domain and domain_txt are different | |
3188 | pointers, in order to get the TXT record from the alternate domain. | |
3189 | ||
3190 | Arguments: | |
3191 | domain the outer dnsbl domain | |
3192 | domain_txt alternate domain to lookup TXT record on success; when the | |
3193 | same domain is to be used, domain_txt == domain (that is, | |
3194 | the pointers must be identical, not just the text) | |
3195 | keydomain the current keydomain (for debug message) | |
3196 | prepend subdomain to lookup (like keydomain, but | |
3197 | reversed if IP address) | |
3198 | iplist the list of matching IP addresses, or NULL for "any" | |
3199 | bitmask true if bitmask matching is wanted | |
3200 | match_type condition for 'succeed' result | |
3201 | 0 => Any RR in iplist (=) | |
3202 | 1 => No RR in iplist (!=) | |
3203 | 2 => All RRs in iplist (==) | |
3204 | 3 => Some RRs not in iplist (!==) | |
3205 | the two bits are defined as MT_NOT and MT_ALL | |
3206 | defer_return what to return for a defer | |
3207 | ||
3208 | Returns: OK if lookup succeeded | |
3209 | FAIL if not | |
3210 | */ | |
3211 | ||
3212 | static int | |
3213 | one_check_dnsbl(uschar *domain, uschar *domain_txt, uschar *keydomain, | |
3214 | uschar *prepend, uschar *iplist, BOOL bitmask, int match_type, | |
3215 | int defer_return) | |
3216 | { | |
3217 | dns_answer dnsa; | |
3218 | dns_scan dnss; | |
3219 | tree_node *t; | |
3220 | dnsbl_cache_block *cb; | |
3221 | int old_pool = store_pool; | |
3222 | uschar query[256]; /* DNS domain max length */ | |
3223 | ||
3224 | /* Construct the specific query domainname */ | |
3225 | ||
3226 | if (!string_format(query, sizeof(query), "%s.%s", prepend, domain)) | |
3227 | { | |
3228 | log_write(0, LOG_MAIN|LOG_PANIC, "dnslist query is too long " | |
3229 | "(ignored): %s...", query); | |
3230 | return FAIL; | |
3231 | } | |
3232 | ||
3233 | /* Look for this query in the cache. */ | |
3234 | ||
3235 | t = tree_search(dnsbl_cache, query); | |
3236 | ||
3237 | /* If not cached from a previous lookup, we must do a DNS lookup, and | |
3238 | cache the result in permanent memory. */ | |
3239 | ||
3240 | if (t == NULL) | |
3241 | { | |
3242 | store_pool = POOL_PERM; | |
3243 | ||
3244 | /* Set up a tree entry to cache the lookup */ | |
3245 | ||
3246 | t = store_get(sizeof(tree_node) + Ustrlen(query)); | |
3247 | Ustrcpy(t->name, query); | |
3248 | t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block)); | |
3249 | (void)tree_insertnode(&dnsbl_cache, t); | |
3250 | ||
3251 | /* Do the DNS loopup . */ | |
3252 | ||
3253 | HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query); | |
3254 | cb->rc = dns_basic_lookup(&dnsa, query, T_A); | |
3255 | cb->text_set = FALSE; | |
3256 | cb->text = NULL; | |
3257 | cb->rhs = NULL; | |
3258 | ||
3259 | /* If the lookup succeeded, cache the RHS address. The code allows for | |
3260 | more than one address - this was for complete generality and the possible | |
3261 | use of A6 records. However, A6 records have been reduced to experimental | |
3262 | status (August 2001) and may die out. So they may never get used at all, | |
3263 | let alone in dnsbl records. However, leave the code here, just in case. | |
3264 | ||
3265 | Quite apart from one A6 RR generating multiple addresses, there are DNS | |
3266 | lists that return more than one A record, so we must handle multiple | |
3267 | addresses generated in that way as well. */ | |
3268 | ||
3269 | if (cb->rc == DNS_SUCCEED) | |
3270 | { | |
3271 | dns_record *rr; | |
3272 | dns_address **addrp = &(cb->rhs); | |
3273 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); | |
3274 | rr != NULL; | |
3275 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) | |
3276 | { | |
3277 | if (rr->type == T_A) | |
3278 | { | |
3279 | dns_address *da = dns_address_from_rr(&dnsa, rr); | |
3280 | if (da != NULL) | |
3281 | { | |
3282 | *addrp = da; | |
3283 | while (da->next != NULL) da = da->next; | |
3284 | addrp = &(da->next); | |
3285 | } | |
3286 | } | |
3287 | } | |
3288 | ||
3289 | /* If we didn't find any A records, change the return code. This can | |
3290 | happen when there is a CNAME record but there are no A records for what | |
3291 | it points to. */ | |
3292 | ||
3293 | if (cb->rhs == NULL) cb->rc = DNS_NODATA; | |
3294 | } | |
3295 | ||
3296 | store_pool = old_pool; | |
3297 | } | |
3298 | ||
3299 | /* Previous lookup was cached */ | |
3300 | ||
3301 | else | |
3302 | { | |
3303 | HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n"); | |
3304 | cb = t->data.ptr; | |
3305 | } | |
3306 | ||
3307 | /* We now have the result of the DNS lookup, either newly done, or cached | |
3308 | from a previous call. If the lookup succeeded, check against the address | |
3309 | list if there is one. This may be a positive equality list (introduced by | |
3310 | "="), a negative equality list (introduced by "!="), a positive bitmask | |
3311 | list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/ | |
3312 | ||
3313 | if (cb->rc == DNS_SUCCEED) | |
3314 | { | |
3315 | dns_address *da = NULL; | |
3316 | uschar *addlist = cb->rhs->address; | |
3317 | ||
3318 | /* For A and AAAA records, there may be multiple addresses from multiple | |
3319 | records. For A6 records (currently not expected to be used) there may be | |
3320 | multiple addresses from a single record. */ | |
3321 | ||
3322 | for (da = cb->rhs->next; da != NULL; da = da->next) | |
3323 | addlist = string_sprintf("%s, %s", addlist, da->address); | |
3324 | ||
3325 | HDEBUG(D_dnsbl) debug_printf("DNS lookup for %s succeeded (yielding %s)\n", | |
3326 | query, addlist); | |
3327 | ||
3328 | /* Address list check; this can be either for equality, or via a bitmask. | |
3329 | In the latter case, all the bits must match. */ | |
3330 | ||
3331 | if (iplist != NULL) | |
3332 | { | |
3333 | for (da = cb->rhs; da != NULL; da = da->next) | |
3334 | { | |
3335 | int ipsep = ','; | |
3336 | uschar ip[46]; | |
3337 | uschar *ptr = iplist; | |
3338 | uschar *res; | |
3339 | ||
3340 | /* Handle exact matching */ | |
3341 | ||
3342 | if (!bitmask) | |
3343 | { | |
3344 | while ((res = string_nextinlist(&ptr, &ipsep, ip, sizeof(ip))) != NULL) | |
3345 | { | |
3346 | if (Ustrcmp(CS da->address, ip) == 0) break; | |
3347 | } | |
3348 | } | |
3349 | ||
3350 | /* Handle bitmask matching */ | |
3351 | ||
3352 | else | |
3353 | { | |
3354 | int address[4]; | |
3355 | int mask = 0; | |
3356 | ||
3357 | /* At present, all known DNS blocking lists use A records, with | |
3358 | IPv4 addresses on the RHS encoding the information they return. I | |
3359 | wonder if this will linger on as the last vestige of IPv4 when IPv6 | |
3360 | is ubiquitous? Anyway, for now we use paranoia code to completely | |
3361 | ignore IPv6 addresses. The default mask is 0, which always matches. | |
3362 | We change this only for IPv4 addresses in the list. */ | |
3363 | ||
3364 | if (host_aton(da->address, address) == 1) mask = address[0]; | |
3365 | ||
3366 | /* Scan the returned addresses, skipping any that are IPv6 */ | |
3367 | ||
3368 | while ((res = string_nextinlist(&ptr, &ipsep, ip, sizeof(ip))) != NULL) | |
3369 | { | |
3370 | if (host_aton(ip, address) != 1) continue; | |
3371 | if ((address[0] & mask) == address[0]) break; | |
3372 | } | |
3373 | } | |
3374 | ||
3375 | /* If either | |
3376 | ||
3377 | (a) An IP address in an any ('=') list matched, or | |
3378 | (b) No IP address in an all ('==') list matched | |
3379 | ||
3380 | then we're done searching. */ | |
3381 | ||
3382 | if (((match_type & MT_ALL) != 0) == (res == NULL)) break; | |
3383 | } | |
3384 | ||
3385 | /* If da == NULL, either | |
3386 | ||
3387 | (a) No IP address in an any ('=') list matched, or | |
3388 | (b) An IP address in an all ('==') list didn't match | |
3389 | ||
3390 | so behave as if the DNSBL lookup had not succeeded, i.e. the host is not on | |
3391 | the list. */ | |
3392 | ||
3393 | if ((match_type == MT_NOT || match_type == MT_ALL) != (da == NULL)) | |
3394 | { | |
3395 | HDEBUG(D_dnsbl) | |
3396 | { | |
3397 | uschar *res = NULL; | |
3398 | switch(match_type) | |
3399 | { | |
3400 | case 0: | |
3401 | res = US"was no match"; | |
3402 | break; | |
3403 | case MT_NOT: | |
3404 | res = US"was an exclude match"; | |
3405 | break; | |
3406 | case MT_ALL: | |
3407 | res = US"was an IP address that did not match"; | |
3408 | break; | |
3409 | case MT_NOT|MT_ALL: | |
3410 | res = US"were no IP addresses that did not match"; | |
3411 | break; | |
3412 | } | |
3413 | debug_printf("=> but we are not accepting this block class because\n"); | |
3414 | debug_printf("=> there %s for %s%c%s\n", | |
3415 | res, | |
3416 | ((match_type & MT_ALL) == 0)? "" : "=", | |
3417 | bitmask? '&' : '=', iplist); | |
3418 | } | |
3419 | return FAIL; | |
3420 | } | |
3421 | } | |
3422 | ||
3423 | /* Either there was no IP list, or the record matched, implying that the | |
3424 | domain is on the list. We now want to find a corresponding TXT record. If an | |
3425 | alternate domain is specified for the TXT record, call this function | |
3426 | recursively to look that up; this has the side effect of re-checking that | |
3427 | there is indeed an A record at the alternate domain. */ | |
3428 | ||
3429 | if (domain_txt != domain) | |
3430 | return one_check_dnsbl(domain_txt, domain_txt, keydomain, prepend, NULL, | |
3431 | FALSE, match_type, defer_return); | |
3432 | ||
3433 | /* If there is no alternate domain, look up a TXT record in the main domain | |
3434 | if it has not previously been cached. */ | |
3435 | ||
3436 | if (!cb->text_set) | |
3437 | { | |
3438 | cb->text_set = TRUE; | |
3439 | if (dns_basic_lookup(&dnsa, query, T_TXT) == DNS_SUCCEED) | |
3440 | { | |
3441 | dns_record *rr; | |
3442 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); | |
3443 | rr != NULL; | |
3444 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) | |
3445 | if (rr->type == T_TXT) break; | |
3446 | if (rr != NULL) | |
3447 | { | |
3448 | int len = (rr->data)[0]; | |
3449 | if (len > 511) len = 127; | |
3450 | store_pool = POOL_PERM; | |
3451 | cb->text = string_sprintf("%.*s", len, (const uschar *)(rr->data+1)); | |
3452 | store_pool = old_pool; | |
3453 | } | |
3454 | } | |
3455 | } | |
3456 | ||
3457 | dnslist_value = addlist; | |
3458 | dnslist_text = cb->text; | |
3459 | return OK; | |
3460 | } | |
3461 | ||
3462 | /* There was a problem with the DNS lookup */ | |
3463 | ||
3464 | if (cb->rc != DNS_NOMATCH && cb->rc != DNS_NODATA) | |
3465 | { | |
3466 | log_write(L_dnslist_defer, LOG_MAIN, | |
3467 | "DNS list lookup defer (probably timeout) for %s: %s", query, | |
3468 | (defer_return == OK)? US"assumed in list" : | |
3469 | (defer_return == FAIL)? US"assumed not in list" : | |
3470 | US"returned DEFER"); | |
3471 | return defer_return; | |
3472 | } | |
3473 | ||
3474 | /* No entry was found in the DNS; continue for next domain */ | |
3475 | ||
3476 | HDEBUG(D_dnsbl) | |
3477 | { | |
3478 | debug_printf("DNS lookup for %s failed\n", query); | |
3479 | debug_printf("=> that means %s is not listed at %s\n", | |
3480 | keydomain, domain); | |
3481 | } | |
3482 | ||
3483 | return FAIL; | |
3484 | } | |
3485 | ||
3486 | ||
3487 | ||
3488 | ||
3489 | /************************************************* | |
3490 | * Check host against DNS black lists * | |
3491 | *************************************************/ | |
3492 | ||
3493 | /* This function runs checks against a list of DNS black lists, until one | |
3494 | matches. Each item on the list can be of the form | |
3495 | ||
3496 | domain=ip-address/key | |
3497 | ||
3498 | The domain is the right-most domain that is used for the query, for example, | |
3499 | blackholes.mail-abuse.org. If the IP address is present, there is a match only | |
3500 | if the DNS lookup returns a matching IP address. Several addresses may be | |
3501 | given, comma-separated, for example: x.y.z=127.0.0.1,127.0.0.2. | |
3502 | ||
3503 | If no key is given, what is looked up in the domain is the inverted IP address | |
3504 | of the current client host. If a key is given, it is used to construct the | |
3505 | domain for the lookup. For example: | |
3506 | ||
3507 | dsn.rfc-ignorant.org/$sender_address_domain | |
3508 | ||
3509 | After finding a match in the DNS, the domain is placed in $dnslist_domain, and | |
3510 | then we check for a TXT record for an error message, and if found, save its | |
3511 | value in $dnslist_text. We also cache everything in a tree, to optimize | |
3512 | multiple lookups. | |
3513 | ||
3514 | The TXT record is normally looked up in the same domain as the A record, but | |
3515 | when many lists are combined in a single DNS domain, this will not be a very | |
3516 | specific message. It is possible to specify a different domain for looking up | |
3517 | TXT records; this is given before the main domain, comma-separated. For | |
3518 | example: | |
3519 | ||
3520 | dnslists = http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \ | |
3521 | socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3 | |
3522 | ||
3523 | The caching ensures that only one lookup in dnsbl.sorbs.net is done. | |
3524 | ||
3525 | Note: an address for testing RBL is 192.203.178.39 | |
3526 | Note: an address for testing DUL is 192.203.178.4 | |
3527 | Note: a domain for testing RFCI is example.tld.dsn.rfc-ignorant.org | |
3528 | ||
3529 | Arguments: | |
3530 | listptr the domain/address/data list | |
3531 | ||
3532 | Returns: OK successful lookup (i.e. the address is on the list), or | |
3533 | lookup deferred after +include_unknown | |
3534 | FAIL name not found, or no data found for the given type, or | |
3535 | lookup deferred after +exclude_unknown (default) | |
3536 | DEFER lookup failure, if +defer_unknown was set | |
3537 | */ | |
3538 | ||
3539 | int | |
3540 | verify_check_dnsbl(uschar **listptr) | |
3541 | { | |
3542 | int sep = 0; | |
3543 | int defer_return = FAIL; | |
3544 | uschar *list = *listptr; | |
3545 | uschar *domain; | |
3546 | uschar *s; | |
3547 | uschar buffer[1024]; | |
3548 | uschar revadd[128]; /* Long enough for IPv6 address */ | |
3549 | ||
3550 | /* Indicate that the inverted IP address is not yet set up */ | |
3551 | ||
3552 | revadd[0] = 0; | |
3553 | ||
3554 | /* In case this is the first time the DNS resolver is being used. */ | |
3555 | ||
3556 | dns_init(FALSE, FALSE, FALSE); /*XXX dnssec? */ | |
3557 | ||
3558 | /* Loop through all the domains supplied, until something matches */ | |
3559 | ||
3560 | while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL) | |
3561 | { | |
3562 | int rc; | |
3563 | BOOL bitmask = FALSE; | |
3564 | int match_type = 0; | |
3565 | uschar *domain_txt; | |
3566 | uschar *comma; | |
3567 | uschar *iplist; | |
3568 | uschar *key; | |
3569 | ||
3570 | HDEBUG(D_dnsbl) debug_printf("DNS list check: %s\n", domain); | |
3571 | ||
3572 | /* Deal with special values that change the behaviour on defer */ | |
3573 | ||
3574 | if (domain[0] == '+') | |
3575 | { | |
3576 | if (strcmpic(domain, US"+include_unknown") == 0) defer_return = OK; | |
3577 | else if (strcmpic(domain, US"+exclude_unknown") == 0) defer_return = FAIL; | |
3578 | else if (strcmpic(domain, US"+defer_unknown") == 0) defer_return = DEFER; | |
3579 | else | |
3580 | log_write(0, LOG_MAIN|LOG_PANIC, "unknown item in dnslist (ignored): %s", | |
3581 | domain); | |
3582 | continue; | |
3583 | } | |
3584 | ||
3585 | /* See if there's explicit data to be looked up */ | |
3586 | ||
3587 | key = Ustrchr(domain, '/'); | |
3588 | if (key != NULL) *key++ = 0; | |
3589 | ||
3590 | /* See if there's a list of addresses supplied after the domain name. This is | |
3591 | introduced by an = or a & character; if preceded by = we require all matches | |
3592 | and if preceded by ! we invert the result. */ | |
3593 | ||
3594 | iplist = Ustrchr(domain, '='); | |
3595 | if (iplist == NULL) | |
3596 | { | |
3597 | bitmask = TRUE; | |
3598 | iplist = Ustrchr(domain, '&'); | |
3599 | } | |
3600 | ||
3601 | if (iplist != NULL) /* Found either = or & */ | |
3602 | { | |
3603 | if (iplist > domain && iplist[-1] == '!') /* Handle preceding ! */ | |
3604 | { | |
3605 | match_type |= MT_NOT; | |
3606 | iplist[-1] = 0; | |
3607 | } | |
3608 | ||
3609 | *iplist++ = 0; /* Terminate domain, move on */ | |
3610 | ||
3611 | /* If we found = (bitmask == FALSE), check for == or =& */ | |
3612 | ||
3613 | if (!bitmask && (*iplist == '=' || *iplist == '&')) | |
3614 | { | |
3615 | bitmask = *iplist++ == '&'; | |
3616 | match_type |= MT_ALL; | |
3617 | } | |
3618 | } | |
3619 | ||
3620 | /* If there is a comma in the domain, it indicates that a second domain for | |
3621 | looking up TXT records is provided, before the main domain. Otherwise we must | |
3622 | set domain_txt == domain. */ | |
3623 | ||
3624 | domain_txt = domain; | |
3625 | comma = Ustrchr(domain, ','); | |
3626 | if (comma != NULL) | |
3627 | { | |
3628 | *comma++ = 0; | |
3629 | domain = comma; | |
3630 | } | |
3631 | ||
3632 | /* Check that what we have left is a sensible domain name. There is no reason | |
3633 | why these domains should in fact use the same syntax as hosts and email | |
3634 | domains, but in practice they seem to. However, there is little point in | |
3635 | actually causing an error here, because that would no doubt hold up incoming | |
3636 | mail. Instead, I'll just log it. */ | |
3637 | ||
3638 | for (s = domain; *s != 0; s++) | |
3639 | { | |
3640 | if (!isalnum(*s) && *s != '-' && *s != '.' && *s != '_') | |
3641 | { | |
3642 | log_write(0, LOG_MAIN, "dnslists domain \"%s\" contains " | |
3643 | "strange characters - is this right?", domain); | |
3644 | break; | |
3645 | } | |
3646 | } | |
3647 | ||
3648 | /* Check the alternate domain if present */ | |
3649 | ||
3650 | if (domain_txt != domain) for (s = domain_txt; *s != 0; s++) | |
3651 | { | |
3652 | if (!isalnum(*s) && *s != '-' && *s != '.' && *s != '_') | |
3653 | { | |
3654 | log_write(0, LOG_MAIN, "dnslists domain \"%s\" contains " | |
3655 | "strange characters - is this right?", domain_txt); | |
3656 | break; | |
3657 | } | |
3658 | } | |
3659 | ||
3660 | /* If there is no key string, construct the query by adding the domain name | |
3661 | onto the inverted host address, and perform a single DNS lookup. */ | |
3662 | ||
3663 | if (key == NULL) | |
3664 | { | |
3665 | if (sender_host_address == NULL) return FAIL; /* can never match */ | |
3666 | if (revadd[0] == 0) invert_address(revadd, sender_host_address); | |
3667 | rc = one_check_dnsbl(domain, domain_txt, sender_host_address, revadd, | |
3668 | iplist, bitmask, match_type, defer_return); | |
3669 | if (rc == OK) | |
3670 | { | |
3671 | dnslist_domain = string_copy(domain_txt); | |
3672 | dnslist_matched = string_copy(sender_host_address); | |
3673 | HDEBUG(D_dnsbl) debug_printf("=> that means %s is listed at %s\n", | |
3674 | sender_host_address, dnslist_domain); | |
3675 | } | |
3676 | if (rc != FAIL) return rc; /* OK or DEFER */ | |
3677 | } | |
3678 | ||
3679 | /* If there is a key string, it can be a list of domains or IP addresses to | |
3680 | be concatenated with the main domain. */ | |
3681 | ||
3682 | else | |
3683 | { | |
3684 | int keysep = 0; | |
3685 | BOOL defer = FALSE; | |
3686 | uschar *keydomain; | |
3687 | uschar keybuffer[256]; | |
3688 | uschar keyrevadd[128]; | |
3689 | ||
3690 | while ((keydomain = string_nextinlist(&key, &keysep, keybuffer, | |
3691 | sizeof(keybuffer))) != NULL) | |
3692 | { | |
3693 | uschar *prepend = keydomain; | |
3694 | ||
3695 | if (string_is_ip_address(keydomain, NULL) != 0) | |
3696 | { | |
3697 | invert_address(keyrevadd, keydomain); | |
3698 | prepend = keyrevadd; | |
3699 | } | |
3700 | ||
3701 | rc = one_check_dnsbl(domain, domain_txt, keydomain, prepend, iplist, | |
3702 | bitmask, match_type, defer_return); | |
3703 | ||
3704 | if (rc == OK) | |
3705 | { | |
3706 | dnslist_domain = string_copy(domain_txt); | |
3707 | dnslist_matched = string_copy(keydomain); | |
3708 | HDEBUG(D_dnsbl) debug_printf("=> that means %s is listed at %s\n", | |
3709 | keydomain, dnslist_domain); | |
3710 | return OK; | |
3711 | } | |
3712 | ||
3713 | /* If the lookup deferred, remember this fact. We keep trying the rest | |
3714 | of the list to see if we get a useful result, and if we don't, we return | |
3715 | DEFER at the end. */ | |
3716 | ||
3717 | if (rc == DEFER) defer = TRUE; | |
3718 | } /* continue with next keystring domain/address */ | |
3719 | ||
3720 | if (defer) return DEFER; | |
3721 | } | |
3722 | } /* continue with next dnsdb outer domain */ | |
3723 | ||
3724 | return FAIL; | |
3725 | } | |
3726 | ||
3727 | /* vi: aw ai sw=2 | |
3728 | */ | |
3729 | /* End of verify.c */ |