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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 | /* Code for handling Access Control Lists (ACLs) */ | |
9 | ||
10 | #include "exim.h" | |
11 | ||
12 | ||
13 | /* Default callout timeout */ | |
14 | ||
15 | #define CALLOUT_TIMEOUT_DEFAULT 30 | |
16 | ||
17 | /* ACL verb codes - keep in step with the table of verbs that follows */ | |
18 | ||
19 | enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE, | |
20 | ACL_WARN }; | |
21 | ||
22 | /* ACL verbs */ | |
23 | ||
24 | static uschar *verbs[] = { | |
25 | US"accept", | |
26 | US"defer", | |
27 | US"deny", | |
28 | US"discard", | |
29 | US"drop", | |
30 | US"require", | |
31 | US"warn" }; | |
32 | ||
33 | /* For each verb, the conditions for which "message" or "log_message" are used | |
34 | are held as a bitmap. This is to avoid expanding the strings unnecessarily. For | |
35 | "accept", the FAIL case is used only after "endpass", but that is selected in | |
36 | the code. */ | |
37 | ||
38 | static int msgcond[] = { | |
39 | (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* accept */ | |
40 | (1<<OK), /* defer */ | |
41 | (1<<OK), /* deny */ | |
42 | (1<<OK) | (1<<FAIL) | (1<<FAIL_DROP), /* discard */ | |
43 | (1<<OK), /* drop */ | |
44 | (1<<FAIL) | (1<<FAIL_DROP), /* require */ | |
45 | (1<<OK) /* warn */ | |
46 | }; | |
47 | ||
48 | /* ACL condition and modifier codes - keep in step with the table that | |
49 | follows, and the cond_expand_at_top and uschar cond_modifiers tables lower | |
50 | down. */ | |
51 | ||
52 | enum { ACLC_ACL, | |
53 | ACLC_ADD_HEADER, | |
54 | ACLC_AUTHENTICATED, | |
55 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
56 | ACLC_BMI_OPTIN, | |
57 | #endif | |
58 | ACLC_CONDITION, | |
59 | ACLC_CONTINUE, | |
60 | ACLC_CONTROL, | |
61 | #ifdef EXPERIMENTAL_DCC | |
62 | ACLC_DCC, | |
63 | #endif | |
64 | #ifdef WITH_CONTENT_SCAN | |
65 | ACLC_DECODE, | |
66 | #endif | |
67 | ACLC_DELAY, | |
68 | #ifdef WITH_OLD_DEMIME | |
69 | ACLC_DEMIME, | |
70 | #endif | |
71 | #ifndef DISABLE_DKIM | |
72 | ACLC_DKIM_SIGNER, | |
73 | ACLC_DKIM_STATUS, | |
74 | #endif | |
75 | #ifdef EXPERIMENTAL_DMARC | |
76 | ACLC_DMARC_STATUS, | |
77 | #endif | |
78 | ACLC_DNSLISTS, | |
79 | ACLC_DOMAINS, | |
80 | ACLC_ENCRYPTED, | |
81 | ACLC_ENDPASS, | |
82 | ACLC_HOSTS, | |
83 | ACLC_LOCAL_PARTS, | |
84 | ACLC_LOG_MESSAGE, | |
85 | ACLC_LOG_REJECT_TARGET, | |
86 | ACLC_LOGWRITE, | |
87 | #ifdef WITH_CONTENT_SCAN | |
88 | ACLC_MALWARE, | |
89 | #endif | |
90 | ACLC_MESSAGE, | |
91 | #ifdef WITH_CONTENT_SCAN | |
92 | ACLC_MIME_REGEX, | |
93 | #endif | |
94 | ACLC_RATELIMIT, | |
95 | ACLC_RECIPIENTS, | |
96 | #ifdef WITH_CONTENT_SCAN | |
97 | ACLC_REGEX, | |
98 | #endif | |
99 | ACLC_REMOVE_HEADER, | |
100 | ACLC_SENDER_DOMAINS, | |
101 | ACLC_SENDERS, | |
102 | ACLC_SET, | |
103 | #ifdef WITH_CONTENT_SCAN | |
104 | ACLC_SPAM, | |
105 | #endif | |
106 | #ifdef EXPERIMENTAL_SPF | |
107 | ACLC_SPF, | |
108 | ACLC_SPF_GUESS, | |
109 | #endif | |
110 | ACLC_UDPSEND, | |
111 | ACLC_VERIFY }; | |
112 | ||
113 | /* ACL conditions/modifiers: "delay", "control", "continue", "endpass", | |
114 | "message", "log_message", "log_reject_target", "logwrite", and "set" are | |
115 | modifiers that look like conditions but always return TRUE. They are used for | |
116 | their side effects. */ | |
117 | ||
118 | static uschar *conditions[] = { | |
119 | US"acl", | |
120 | US"add_header", | |
121 | US"authenticated", | |
122 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
123 | US"bmi_optin", | |
124 | #endif | |
125 | US"condition", | |
126 | US"continue", | |
127 | US"control", | |
128 | #ifdef EXPERIMENTAL_DCC | |
129 | US"dcc", | |
130 | #endif | |
131 | #ifdef WITH_CONTENT_SCAN | |
132 | US"decode", | |
133 | #endif | |
134 | US"delay", | |
135 | #ifdef WITH_OLD_DEMIME | |
136 | US"demime", | |
137 | #endif | |
138 | #ifndef DISABLE_DKIM | |
139 | US"dkim_signers", | |
140 | US"dkim_status", | |
141 | #endif | |
142 | #ifdef EXPERIMENTAL_DMARC | |
143 | US"dmarc_status", | |
144 | #endif | |
145 | US"dnslists", | |
146 | US"domains", | |
147 | US"encrypted", | |
148 | US"endpass", | |
149 | US"hosts", | |
150 | US"local_parts", | |
151 | US"log_message", | |
152 | US"log_reject_target", | |
153 | US"logwrite", | |
154 | #ifdef WITH_CONTENT_SCAN | |
155 | US"malware", | |
156 | #endif | |
157 | US"message", | |
158 | #ifdef WITH_CONTENT_SCAN | |
159 | US"mime_regex", | |
160 | #endif | |
161 | US"ratelimit", | |
162 | US"recipients", | |
163 | #ifdef WITH_CONTENT_SCAN | |
164 | US"regex", | |
165 | #endif | |
166 | US"remove_header", | |
167 | US"sender_domains", US"senders", US"set", | |
168 | #ifdef WITH_CONTENT_SCAN | |
169 | US"spam", | |
170 | #endif | |
171 | #ifdef EXPERIMENTAL_SPF | |
172 | US"spf", | |
173 | US"spf_guess", | |
174 | #endif | |
175 | US"udpsend", | |
176 | US"verify" }; | |
177 | ||
178 | ||
179 | /* Return values from decode_control(); keep in step with the table of names | |
180 | that follows! */ | |
181 | ||
182 | enum { | |
183 | CONTROL_AUTH_UNADVERTISED, | |
184 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
185 | CONTROL_BMI_RUN, | |
186 | #endif | |
187 | CONTROL_DEBUG, | |
188 | #ifndef DISABLE_DKIM | |
189 | CONTROL_DKIM_VERIFY, | |
190 | #endif | |
191 | #ifdef EXPERIMENTAL_DMARC | |
192 | CONTROL_DMARC_VERIFY, | |
193 | CONTROL_DMARC_FORENSIC, | |
194 | #endif | |
195 | CONTROL_DSCP, | |
196 | CONTROL_ERROR, | |
197 | CONTROL_CASEFUL_LOCAL_PART, | |
198 | CONTROL_CASELOWER_LOCAL_PART, | |
199 | CONTROL_CUTTHROUGH_DELIVERY, | |
200 | CONTROL_ENFORCE_SYNC, | |
201 | CONTROL_NO_ENFORCE_SYNC, | |
202 | CONTROL_FREEZE, | |
203 | CONTROL_QUEUE_ONLY, | |
204 | CONTROL_SUBMISSION, | |
205 | CONTROL_SUPPRESS_LOCAL_FIXUPS, | |
206 | #ifdef WITH_CONTENT_SCAN | |
207 | CONTROL_NO_MBOX_UNSPOOL, | |
208 | #endif | |
209 | CONTROL_FAKEDEFER, | |
210 | CONTROL_FAKEREJECT, | |
211 | CONTROL_NO_MULTILINE, | |
212 | CONTROL_NO_PIPELINING, | |
213 | CONTROL_NO_DELAY_FLUSH, | |
214 | CONTROL_NO_CALLOUT_FLUSH | |
215 | }; | |
216 | ||
217 | /* ACL control names; keep in step with the table above! This list is used for | |
218 | turning ids into names. The actual list of recognized names is in the variable | |
219 | control_def controls_list[] below. The fact that there are two lists is a mess | |
220 | and should be tidied up. */ | |
221 | ||
222 | static uschar *controls[] = { | |
223 | US"allow_auth_unadvertised", | |
224 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
225 | US"bmi_run", | |
226 | #endif | |
227 | US"debug", | |
228 | #ifndef DISABLE_DKIM | |
229 | US"dkim_disable_verify", | |
230 | #endif | |
231 | #ifdef EXPERIMENTAL_DMARC | |
232 | US"dmarc_disable_verify", | |
233 | US"dmarc_enable_forensic", | |
234 | #endif | |
235 | US"dscp", | |
236 | US"error", | |
237 | US"caseful_local_part", | |
238 | US"caselower_local_part", | |
239 | US"cutthrough_delivery", | |
240 | US"enforce_sync", | |
241 | US"no_enforce_sync", | |
242 | US"freeze", | |
243 | US"queue_only", | |
244 | US"submission", | |
245 | US"suppress_local_fixups", | |
246 | #ifdef WITH_CONTENT_SCAN | |
247 | US"no_mbox_unspool", | |
248 | #endif | |
249 | US"fakedefer", | |
250 | US"fakereject", | |
251 | US"no_multiline_responses", | |
252 | US"no_pipelining", | |
253 | US"no_delay_flush", | |
254 | US"no_callout_flush" | |
255 | }; | |
256 | ||
257 | /* Flags to indicate for which conditions/modifiers a string expansion is done | |
258 | at the outer level. In the other cases, expansion already occurs in the | |
259 | checking functions. */ | |
260 | ||
261 | static uschar cond_expand_at_top[] = { | |
262 | FALSE, /* acl */ | |
263 | TRUE, /* add_header */ | |
264 | FALSE, /* authenticated */ | |
265 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
266 | TRUE, /* bmi_optin */ | |
267 | #endif | |
268 | TRUE, /* condition */ | |
269 | TRUE, /* continue */ | |
270 | TRUE, /* control */ | |
271 | #ifdef EXPERIMENTAL_DCC | |
272 | TRUE, /* dcc */ | |
273 | #endif | |
274 | #ifdef WITH_CONTENT_SCAN | |
275 | TRUE, /* decode */ | |
276 | #endif | |
277 | TRUE, /* delay */ | |
278 | #ifdef WITH_OLD_DEMIME | |
279 | TRUE, /* demime */ | |
280 | #endif | |
281 | #ifndef DISABLE_DKIM | |
282 | TRUE, /* dkim_signers */ | |
283 | TRUE, /* dkim_status */ | |
284 | #endif | |
285 | #ifdef EXPERIMENTAL_DMARC | |
286 | TRUE, /* dmarc_status */ | |
287 | #endif | |
288 | TRUE, /* dnslists */ | |
289 | FALSE, /* domains */ | |
290 | FALSE, /* encrypted */ | |
291 | TRUE, /* endpass */ | |
292 | FALSE, /* hosts */ | |
293 | FALSE, /* local_parts */ | |
294 | TRUE, /* log_message */ | |
295 | TRUE, /* log_reject_target */ | |
296 | TRUE, /* logwrite */ | |
297 | #ifdef WITH_CONTENT_SCAN | |
298 | TRUE, /* malware */ | |
299 | #endif | |
300 | TRUE, /* message */ | |
301 | #ifdef WITH_CONTENT_SCAN | |
302 | TRUE, /* mime_regex */ | |
303 | #endif | |
304 | TRUE, /* ratelimit */ | |
305 | FALSE, /* recipients */ | |
306 | #ifdef WITH_CONTENT_SCAN | |
307 | TRUE, /* regex */ | |
308 | #endif | |
309 | TRUE, /* remove_header */ | |
310 | FALSE, /* sender_domains */ | |
311 | FALSE, /* senders */ | |
312 | TRUE, /* set */ | |
313 | #ifdef WITH_CONTENT_SCAN | |
314 | TRUE, /* spam */ | |
315 | #endif | |
316 | #ifdef EXPERIMENTAL_SPF | |
317 | TRUE, /* spf */ | |
318 | TRUE, /* spf_guess */ | |
319 | #endif | |
320 | TRUE, /* udpsend */ | |
321 | TRUE /* verify */ | |
322 | }; | |
323 | ||
324 | /* Flags to identify the modifiers */ | |
325 | ||
326 | static uschar cond_modifiers[] = { | |
327 | FALSE, /* acl */ | |
328 | TRUE, /* add_header */ | |
329 | FALSE, /* authenticated */ | |
330 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
331 | TRUE, /* bmi_optin */ | |
332 | #endif | |
333 | FALSE, /* condition */ | |
334 | TRUE, /* continue */ | |
335 | TRUE, /* control */ | |
336 | #ifdef EXPERIMENTAL_DCC | |
337 | FALSE, /* dcc */ | |
338 | #endif | |
339 | #ifdef WITH_CONTENT_SCAN | |
340 | FALSE, /* decode */ | |
341 | #endif | |
342 | TRUE, /* delay */ | |
343 | #ifdef WITH_OLD_DEMIME | |
344 | FALSE, /* demime */ | |
345 | #endif | |
346 | #ifndef DISABLE_DKIM | |
347 | FALSE, /* dkim_signers */ | |
348 | FALSE, /* dkim_status */ | |
349 | #endif | |
350 | #ifdef EXPERIMENTAL_DMARC | |
351 | FALSE, /* dmarc_status */ | |
352 | #endif | |
353 | FALSE, /* dnslists */ | |
354 | FALSE, /* domains */ | |
355 | FALSE, /* encrypted */ | |
356 | TRUE, /* endpass */ | |
357 | FALSE, /* hosts */ | |
358 | FALSE, /* local_parts */ | |
359 | TRUE, /* log_message */ | |
360 | TRUE, /* log_reject_target */ | |
361 | TRUE, /* logwrite */ | |
362 | #ifdef WITH_CONTENT_SCAN | |
363 | FALSE, /* malware */ | |
364 | #endif | |
365 | TRUE, /* message */ | |
366 | #ifdef WITH_CONTENT_SCAN | |
367 | FALSE, /* mime_regex */ | |
368 | #endif | |
369 | FALSE, /* ratelimit */ | |
370 | FALSE, /* recipients */ | |
371 | #ifdef WITH_CONTENT_SCAN | |
372 | FALSE, /* regex */ | |
373 | #endif | |
374 | TRUE, /* remove_header */ | |
375 | FALSE, /* sender_domains */ | |
376 | FALSE, /* senders */ | |
377 | TRUE, /* set */ | |
378 | #ifdef WITH_CONTENT_SCAN | |
379 | FALSE, /* spam */ | |
380 | #endif | |
381 | #ifdef EXPERIMENTAL_SPF | |
382 | FALSE, /* spf */ | |
383 | FALSE, /* spf_guess */ | |
384 | #endif | |
385 | TRUE, /* udpsend */ | |
386 | FALSE /* verify */ | |
387 | }; | |
388 | ||
389 | /* Bit map vector of which conditions and modifiers are not allowed at certain | |
390 | times. For each condition and modifier, there's a bitmap of dis-allowed times. | |
391 | For some, it is easier to specify the negation of a small number of allowed | |
392 | times. */ | |
393 | ||
394 | static unsigned int cond_forbids[] = { | |
395 | 0, /* acl */ | |
396 | ||
397 | (unsigned int) | |
398 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* add_header */ | |
399 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
400 | #ifndef DISABLE_PRDR | |
401 | (1<<ACL_WHERE_PRDR)| | |
402 | #endif | |
403 | (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)| | |
404 | (1<<ACL_WHERE_DKIM)| | |
405 | (1<<ACL_WHERE_NOTSMTP_START)), | |
406 | ||
407 | (1<<ACL_WHERE_NOTSMTP)| /* authenticated */ | |
408 | (1<<ACL_WHERE_NOTSMTP_START)| | |
409 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO), | |
410 | ||
411 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
412 | (1<<ACL_WHERE_AUTH)| /* bmi_optin */ | |
413 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| | |
414 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)| | |
415 | #ifndef DISABLE_PRDR | |
416 | (1<<ACL_WHERE_PRDR)| | |
417 | #endif | |
418 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| | |
419 | (1<<ACL_WHERE_MAILAUTH)| | |
420 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| | |
421 | (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA)| | |
422 | (1<<ACL_WHERE_NOTSMTP_START), | |
423 | #endif | |
424 | ||
425 | 0, /* condition */ | |
426 | ||
427 | 0, /* continue */ | |
428 | ||
429 | /* Certain types of control are always allowed, so we let it through | |
430 | always and check in the control processing itself. */ | |
431 | ||
432 | 0, /* control */ | |
433 | ||
434 | #ifdef EXPERIMENTAL_DCC | |
435 | (unsigned int) | |
436 | ~((1<<ACL_WHERE_DATA)| /* dcc */ | |
437 | #ifndef DISABLE_PRDR | |
438 | (1<<ACL_WHERE_PRDR)| | |
439 | #endif | |
440 | (1<<ACL_WHERE_NOTSMTP)), | |
441 | #endif | |
442 | ||
443 | #ifdef WITH_CONTENT_SCAN | |
444 | (unsigned int) | |
445 | ~(1<<ACL_WHERE_MIME), /* decode */ | |
446 | #endif | |
447 | ||
448 | (1<<ACL_WHERE_NOTQUIT), /* delay */ | |
449 | ||
450 | #ifdef WITH_OLD_DEMIME | |
451 | (unsigned int) | |
452 | ~((1<<ACL_WHERE_DATA)| /* demime */ | |
453 | #ifndef DISABLE_PRDR | |
454 | (1<<ACL_WHERE_PRDR)| | |
455 | #endif | |
456 | (1<<ACL_WHERE_NOTSMTP)), | |
457 | #endif | |
458 | ||
459 | #ifndef DISABLE_DKIM | |
460 | (unsigned int) | |
461 | ~(1<<ACL_WHERE_DKIM), /* dkim_signers */ | |
462 | ||
463 | (unsigned int) | |
464 | ~(1<<ACL_WHERE_DKIM), /* dkim_status */ | |
465 | #endif | |
466 | ||
467 | #ifdef EXPERIMENTAL_DMARC | |
468 | (unsigned int) | |
469 | ~(1<<ACL_WHERE_DATA), /* dmarc_status */ | |
470 | #endif | |
471 | ||
472 | (1<<ACL_WHERE_NOTSMTP)| /* dnslists */ | |
473 | (1<<ACL_WHERE_NOTSMTP_START), | |
474 | ||
475 | (unsigned int) | |
476 | ~((1<<ACL_WHERE_RCPT) /* domains */ | |
477 | #ifndef DISABLE_PRDR | |
478 | |(1<<ACL_WHERE_PRDR) | |
479 | #endif | |
480 | ), | |
481 | ||
482 | (1<<ACL_WHERE_NOTSMTP)| /* encrypted */ | |
483 | (1<<ACL_WHERE_CONNECT)| | |
484 | (1<<ACL_WHERE_NOTSMTP_START)| | |
485 | (1<<ACL_WHERE_HELO), | |
486 | ||
487 | 0, /* endpass */ | |
488 | ||
489 | (1<<ACL_WHERE_NOTSMTP)| /* hosts */ | |
490 | (1<<ACL_WHERE_NOTSMTP_START), | |
491 | ||
492 | (unsigned int) | |
493 | ~((1<<ACL_WHERE_RCPT) /* local_parts */ | |
494 | #ifndef DISABLE_PRDR | |
495 | |(1<<ACL_WHERE_PRDR) | |
496 | #endif | |
497 | ), | |
498 | ||
499 | 0, /* log_message */ | |
500 | ||
501 | 0, /* log_reject_target */ | |
502 | ||
503 | 0, /* logwrite */ | |
504 | ||
505 | #ifdef WITH_CONTENT_SCAN | |
506 | (unsigned int) | |
507 | ~((1<<ACL_WHERE_DATA)| /* malware */ | |
508 | #ifndef DISABLE_PRDR | |
509 | (1<<ACL_WHERE_PRDR)| | |
510 | #endif | |
511 | (1<<ACL_WHERE_NOTSMTP)), | |
512 | #endif | |
513 | ||
514 | 0, /* message */ | |
515 | ||
516 | #ifdef WITH_CONTENT_SCAN | |
517 | (unsigned int) | |
518 | ~(1<<ACL_WHERE_MIME), /* mime_regex */ | |
519 | #endif | |
520 | ||
521 | 0, /* ratelimit */ | |
522 | ||
523 | (unsigned int) | |
524 | ~(1<<ACL_WHERE_RCPT), /* recipients */ | |
525 | ||
526 | #ifdef WITH_CONTENT_SCAN | |
527 | (unsigned int) | |
528 | ~((1<<ACL_WHERE_DATA)| /* regex */ | |
529 | #ifndef DISABLE_PRDR | |
530 | (1<<ACL_WHERE_PRDR)| | |
531 | #endif | |
532 | (1<<ACL_WHERE_NOTSMTP)| | |
533 | (1<<ACL_WHERE_MIME)), | |
534 | #endif | |
535 | ||
536 | (unsigned int) | |
537 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* remove_header */ | |
538 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
539 | #ifndef DISABLE_PRDR | |
540 | (1<<ACL_WHERE_PRDR)| | |
541 | #endif | |
542 | (1<<ACL_WHERE_MIME)|(1<<ACL_WHERE_NOTSMTP)| | |
543 | (1<<ACL_WHERE_NOTSMTP_START)), | |
544 | ||
545 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */ | |
546 | (1<<ACL_WHERE_HELO)| | |
547 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| | |
548 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| | |
549 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY), | |
550 | ||
551 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */ | |
552 | (1<<ACL_WHERE_HELO)| | |
553 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| | |
554 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| | |
555 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY), | |
556 | ||
557 | 0, /* set */ | |
558 | ||
559 | #ifdef WITH_CONTENT_SCAN | |
560 | (unsigned int) | |
561 | ~((1<<ACL_WHERE_DATA)| /* spam */ | |
562 | #ifndef DISABLE_PRDR | |
563 | (1<<ACL_WHERE_PRDR)| | |
564 | #endif | |
565 | (1<<ACL_WHERE_NOTSMTP)), | |
566 | #endif | |
567 | ||
568 | #ifdef EXPERIMENTAL_SPF | |
569 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */ | |
570 | (1<<ACL_WHERE_HELO)| | |
571 | (1<<ACL_WHERE_MAILAUTH)| | |
572 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| | |
573 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)| | |
574 | (1<<ACL_WHERE_NOTSMTP)| | |
575 | (1<<ACL_WHERE_NOTSMTP_START), | |
576 | ||
577 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf_guess */ | |
578 | (1<<ACL_WHERE_HELO)| | |
579 | (1<<ACL_WHERE_MAILAUTH)| | |
580 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| | |
581 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY)| | |
582 | (1<<ACL_WHERE_NOTSMTP)| | |
583 | (1<<ACL_WHERE_NOTSMTP_START), | |
584 | #endif | |
585 | ||
586 | 0, /* udpsend */ | |
587 | ||
588 | /* Certain types of verify are always allowed, so we let it through | |
589 | always and check in the verify function itself */ | |
590 | ||
591 | 0 /* verify */ | |
592 | }; | |
593 | ||
594 | ||
595 | /* Bit map vector of which controls are not allowed at certain times. For | |
596 | each control, there's a bitmap of dis-allowed times. For some, it is easier to | |
597 | specify the negation of a small number of allowed times. */ | |
598 | ||
599 | static unsigned int control_forbids[] = { | |
600 | (unsigned int) | |
601 | ~((1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)), /* allow_auth_unadvertised */ | |
602 | ||
603 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
604 | 0, /* bmi_run */ | |
605 | #endif | |
606 | ||
607 | 0, /* debug */ | |
608 | ||
609 | #ifndef DISABLE_DKIM | |
610 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dkim_disable_verify */ | |
611 | #ifndef DISABLE_PRDR | |
612 | (1<<ACL_WHERE_PRDR)| | |
613 | #endif | |
614 | (1<<ACL_WHERE_NOTSMTP_START), | |
615 | #endif | |
616 | ||
617 | #ifdef EXPERIMENTAL_DMARC | |
618 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_disable_verify */ | |
619 | (1<<ACL_WHERE_NOTSMTP_START), | |
620 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* dmarc_enable_forensic */ | |
621 | (1<<ACL_WHERE_NOTSMTP_START), | |
622 | #endif | |
623 | ||
624 | (1<<ACL_WHERE_NOTSMTP)| | |
625 | (1<<ACL_WHERE_NOTSMTP_START)| | |
626 | (1<<ACL_WHERE_NOTQUIT), /* dscp */ | |
627 | ||
628 | 0, /* error */ | |
629 | ||
630 | (unsigned int) | |
631 | ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */ | |
632 | ||
633 | (unsigned int) | |
634 | ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */ | |
635 | ||
636 | (unsigned int) | |
637 | 0, /* cutthrough_delivery */ | |
638 | ||
639 | (1<<ACL_WHERE_NOTSMTP)| /* enforce_sync */ | |
640 | (1<<ACL_WHERE_NOTSMTP_START), | |
641 | ||
642 | (1<<ACL_WHERE_NOTSMTP)| /* no_enforce_sync */ | |
643 | (1<<ACL_WHERE_NOTSMTP_START), | |
644 | ||
645 | (unsigned int) | |
646 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */ | |
647 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
648 | // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */ | |
649 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)), | |
650 | ||
651 | (unsigned int) | |
652 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */ | |
653 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
654 | // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */ | |
655 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)), | |
656 | ||
657 | (unsigned int) | |
658 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */ | |
659 | (1<<ACL_WHERE_PREDATA)), | |
660 | ||
661 | (unsigned int) | |
662 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* suppress_local_fixups */ | |
663 | (1<<ACL_WHERE_PREDATA)| | |
664 | (1<<ACL_WHERE_NOTSMTP_START)), | |
665 | ||
666 | #ifdef WITH_CONTENT_SCAN | |
667 | (unsigned int) | |
668 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */ | |
669 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
670 | // (1<<ACL_WHERE_PRDR)| /* Not allow one user to freeze for all */ | |
671 | (1<<ACL_WHERE_MIME)), | |
672 | #endif | |
673 | ||
674 | (unsigned int) | |
675 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */ | |
676 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
677 | #ifndef DISABLE_PRDR | |
678 | (1<<ACL_WHERE_PRDR)| | |
679 | #endif | |
680 | (1<<ACL_WHERE_MIME)), | |
681 | ||
682 | (unsigned int) | |
683 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */ | |
684 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| | |
685 | #ifndef DISABLE_PRDR | |
686 | (1<<ACL_WHERE_PRDR)| | |
687 | #endif | |
688 | (1<<ACL_WHERE_MIME)), | |
689 | ||
690 | (1<<ACL_WHERE_NOTSMTP)| /* no_multiline */ | |
691 | (1<<ACL_WHERE_NOTSMTP_START), | |
692 | ||
693 | (1<<ACL_WHERE_NOTSMTP)| /* no_pipelining */ | |
694 | (1<<ACL_WHERE_NOTSMTP_START), | |
695 | ||
696 | (1<<ACL_WHERE_NOTSMTP)| /* no_delay_flush */ | |
697 | (1<<ACL_WHERE_NOTSMTP_START), | |
698 | ||
699 | (1<<ACL_WHERE_NOTSMTP)| /* no_callout_flush */ | |
700 | (1<<ACL_WHERE_NOTSMTP_START) | |
701 | }; | |
702 | ||
703 | /* Structure listing various control arguments, with their characteristics. */ | |
704 | ||
705 | typedef struct control_def { | |
706 | uschar *name; | |
707 | int value; /* CONTROL_xxx value */ | |
708 | BOOL has_option; /* Has /option(s) following */ | |
709 | } control_def; | |
710 | ||
711 | static control_def controls_list[] = { | |
712 | { US"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED, FALSE }, | |
713 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
714 | { US"bmi_run", CONTROL_BMI_RUN, FALSE }, | |
715 | #endif | |
716 | { US"debug", CONTROL_DEBUG, TRUE }, | |
717 | #ifndef DISABLE_DKIM | |
718 | { US"dkim_disable_verify", CONTROL_DKIM_VERIFY, FALSE }, | |
719 | #endif | |
720 | #ifdef EXPERIMENTAL_DMARC | |
721 | { US"dmarc_disable_verify", CONTROL_DMARC_VERIFY, FALSE }, | |
722 | { US"dmarc_enable_forensic", CONTROL_DMARC_FORENSIC, FALSE }, | |
723 | #endif | |
724 | { US"dscp", CONTROL_DSCP, TRUE }, | |
725 | { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE }, | |
726 | { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE }, | |
727 | { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE }, | |
728 | { US"freeze", CONTROL_FREEZE, TRUE }, | |
729 | { US"no_callout_flush", CONTROL_NO_CALLOUT_FLUSH, FALSE }, | |
730 | { US"no_delay_flush", CONTROL_NO_DELAY_FLUSH, FALSE }, | |
731 | { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE }, | |
732 | { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE }, | |
733 | { US"no_pipelining", CONTROL_NO_PIPELINING, FALSE }, | |
734 | { US"queue_only", CONTROL_QUEUE_ONLY, FALSE }, | |
735 | #ifdef WITH_CONTENT_SCAN | |
736 | { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE }, | |
737 | #endif | |
738 | { US"fakedefer", CONTROL_FAKEDEFER, TRUE }, | |
739 | { US"fakereject", CONTROL_FAKEREJECT, TRUE }, | |
740 | { US"submission", CONTROL_SUBMISSION, TRUE }, | |
741 | { US"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS, FALSE }, | |
742 | { US"cutthrough_delivery", CONTROL_CUTTHROUGH_DELIVERY, FALSE } | |
743 | }; | |
744 | ||
745 | /* Support data structures for Client SMTP Authorization. acl_verify_csa() | |
746 | caches its result in a tree to avoid repeated DNS queries. The result is an | |
747 | integer code which is used as an index into the following tables of | |
748 | explanatory strings and verification return codes. */ | |
749 | ||
750 | static tree_node *csa_cache = NULL; | |
751 | ||
752 | enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR, | |
753 | CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH }; | |
754 | ||
755 | /* The acl_verify_csa() return code is translated into an acl_verify() return | |
756 | code using the following table. It is OK unless the client is definitely not | |
757 | authorized. This is because CSA is supposed to be optional for sending sites, | |
758 | so recipients should not be too strict about checking it - especially because | |
759 | DNS problems are quite likely to occur. It's possible to use $csa_status in | |
760 | further ACL conditions to distinguish ok, unknown, and defer if required, but | |
761 | the aim is to make the usual configuration simple. */ | |
762 | ||
763 | static int csa_return_code[] = { | |
764 | OK, OK, OK, OK, | |
765 | FAIL, FAIL, FAIL, FAIL | |
766 | }; | |
767 | ||
768 | static uschar *csa_status_string[] = { | |
769 | US"unknown", US"ok", US"defer", US"defer", | |
770 | US"fail", US"fail", US"fail", US"fail" | |
771 | }; | |
772 | ||
773 | static uschar *csa_reason_string[] = { | |
774 | US"unknown", | |
775 | US"ok", | |
776 | US"deferred (SRV lookup failed)", | |
777 | US"deferred (target address lookup failed)", | |
778 | US"failed (explicit authorization required)", | |
779 | US"failed (host name not authorized)", | |
780 | US"failed (no authorized addresses)", | |
781 | US"failed (client address mismatch)" | |
782 | }; | |
783 | ||
784 | /* Options for the ratelimit condition. Note that there are two variants of | |
785 | the per_rcpt option, depending on the ACL that is used to measure the rate. | |
786 | However any ACL must be able to look up per_rcpt rates in /noupdate mode, | |
787 | so the two variants must have the same internal representation as well as | |
788 | the same configuration string. */ | |
789 | ||
790 | enum { | |
791 | RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD, | |
792 | RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS | |
793 | }; | |
794 | ||
795 | #define RATE_SET(var,new) \ | |
796 | (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH)) | |
797 | ||
798 | static uschar *ratelimit_option_string[] = { | |
799 | US"?", US"!", US"per_addr", US"per_byte", US"per_cmd", | |
800 | US"per_conn", US"per_mail", US"per_rcpt", US"per_rcpt" | |
801 | }; | |
802 | ||
803 | /* Enable recursion between acl_check_internal() and acl_check_condition() */ | |
804 | ||
805 | static int acl_check_wargs(int, address_item *, uschar *, int, uschar **, | |
806 | uschar **); | |
807 | ||
808 | ||
809 | /************************************************* | |
810 | * Pick out name from list * | |
811 | *************************************************/ | |
812 | ||
813 | /* Use a binary chop method | |
814 | ||
815 | Arguments: | |
816 | name name to find | |
817 | list list of names | |
818 | end size of list | |
819 | ||
820 | Returns: offset in list, or -1 if not found | |
821 | */ | |
822 | ||
823 | static int | |
824 | acl_checkname(uschar *name, uschar **list, int end) | |
825 | { | |
826 | int start = 0; | |
827 | ||
828 | while (start < end) | |
829 | { | |
830 | int mid = (start + end)/2; | |
831 | int c = Ustrcmp(name, list[mid]); | |
832 | if (c == 0) return mid; | |
833 | if (c < 0) end = mid; else start = mid + 1; | |
834 | } | |
835 | ||
836 | return -1; | |
837 | } | |
838 | ||
839 | ||
840 | /************************************************* | |
841 | * Read and parse one ACL * | |
842 | *************************************************/ | |
843 | ||
844 | /* This function is called both from readconf in order to parse the ACLs in the | |
845 | configuration file, and also when an ACL is encountered dynamically (e.g. as | |
846 | the result of an expansion). It is given a function to call in order to | |
847 | retrieve the lines of the ACL. This function handles skipping comments and | |
848 | blank lines (where relevant). | |
849 | ||
850 | Arguments: | |
851 | func function to get next line of ACL | |
852 | error where to put an error message | |
853 | ||
854 | Returns: pointer to ACL, or NULL | |
855 | NULL can be legal (empty ACL); in this case error will be NULL | |
856 | */ | |
857 | ||
858 | acl_block * | |
859 | acl_read(uschar *(*func)(void), uschar **error) | |
860 | { | |
861 | acl_block *yield = NULL; | |
862 | acl_block **lastp = &yield; | |
863 | acl_block *this = NULL; | |
864 | acl_condition_block *cond; | |
865 | acl_condition_block **condp = NULL; | |
866 | uschar *s; | |
867 | ||
868 | *error = NULL; | |
869 | ||
870 | while ((s = (*func)()) != NULL) | |
871 | { | |
872 | int v, c; | |
873 | BOOL negated = FALSE; | |
874 | uschar *saveline = s; | |
875 | uschar name[64]; | |
876 | ||
877 | /* Conditions (but not verbs) are allowed to be negated by an initial | |
878 | exclamation mark. */ | |
879 | ||
880 | while (isspace(*s)) s++; | |
881 | if (*s == '!') | |
882 | { | |
883 | negated = TRUE; | |
884 | s++; | |
885 | } | |
886 | ||
887 | /* Read the name of a verb or a condition, or the start of a new ACL, which | |
888 | can be started by a name, or by a macro definition. */ | |
889 | ||
890 | s = readconf_readname(name, sizeof(name), s); | |
891 | if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield; | |
892 | ||
893 | /* If a verb is unrecognized, it may be another condition or modifier that | |
894 | continues the previous verb. */ | |
895 | ||
896 | v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *)); | |
897 | if (v < 0) | |
898 | { | |
899 | if (this == NULL) | |
900 | { | |
901 | *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name, | |
902 | saveline); | |
903 | return NULL; | |
904 | } | |
905 | } | |
906 | ||
907 | /* New verb */ | |
908 | ||
909 | else | |
910 | { | |
911 | if (negated) | |
912 | { | |
913 | *error = string_sprintf("malformed ACL line \"%s\"", saveline); | |
914 | return NULL; | |
915 | } | |
916 | this = store_get(sizeof(acl_block)); | |
917 | *lastp = this; | |
918 | lastp = &(this->next); | |
919 | this->next = NULL; | |
920 | this->verb = v; | |
921 | this->condition = NULL; | |
922 | condp = &(this->condition); | |
923 | if (*s == 0) continue; /* No condition on this line */ | |
924 | if (*s == '!') | |
925 | { | |
926 | negated = TRUE; | |
927 | s++; | |
928 | } | |
929 | s = readconf_readname(name, sizeof(name), s); /* Condition name */ | |
930 | } | |
931 | ||
932 | /* Handle a condition or modifier. */ | |
933 | ||
934 | c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *)); | |
935 | if (c < 0) | |
936 | { | |
937 | *error = string_sprintf("unknown ACL condition/modifier in \"%s\"", | |
938 | saveline); | |
939 | return NULL; | |
940 | } | |
941 | ||
942 | /* The modifiers may not be negated */ | |
943 | ||
944 | if (negated && cond_modifiers[c]) | |
945 | { | |
946 | *error = string_sprintf("ACL error: negation is not allowed with " | |
947 | "\"%s\"", conditions[c]); | |
948 | return NULL; | |
949 | } | |
950 | ||
951 | /* ENDPASS may occur only with ACCEPT or DISCARD. */ | |
952 | ||
953 | if (c == ACLC_ENDPASS && | |
954 | this->verb != ACL_ACCEPT && | |
955 | this->verb != ACL_DISCARD) | |
956 | { | |
957 | *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"", | |
958 | conditions[c], verbs[this->verb]); | |
959 | return NULL; | |
960 | } | |
961 | ||
962 | cond = store_get(sizeof(acl_condition_block)); | |
963 | cond->next = NULL; | |
964 | cond->type = c; | |
965 | cond->u.negated = negated; | |
966 | ||
967 | *condp = cond; | |
968 | condp = &(cond->next); | |
969 | ||
970 | /* The "set" modifier is different in that its argument is "name=value" | |
971 | rather than just a value, and we can check the validity of the name, which | |
972 | gives us a variable name to insert into the data block. The original ACL | |
973 | variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was | |
974 | extended to 20 of each type, but after that people successfully argued for | |
975 | arbitrary names. In the new scheme, the names must start with acl_c or acl_m. | |
976 | After that, we allow alphanumerics and underscores, but the first character | |
977 | after c or m must be a digit or an underscore. This retains backwards | |
978 | compatibility. */ | |
979 | ||
980 | if (c == ACLC_SET) | |
981 | { | |
982 | uschar *endptr; | |
983 | ||
984 | if (Ustrncmp(s, "acl_c", 5) != 0 && | |
985 | Ustrncmp(s, "acl_m", 5) != 0) | |
986 | { | |
987 | *error = string_sprintf("invalid variable name after \"set\" in ACL " | |
988 | "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s); | |
989 | return NULL; | |
990 | } | |
991 | ||
992 | endptr = s + 5; | |
993 | if (!isdigit(*endptr) && *endptr != '_') | |
994 | { | |
995 | *error = string_sprintf("invalid variable name after \"set\" in ACL " | |
996 | "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)", | |
997 | s); | |
998 | return NULL; | |
999 | } | |
1000 | ||
1001 | while (*endptr != 0 && *endptr != '=' && !isspace(*endptr)) | |
1002 | { | |
1003 | if (!isalnum(*endptr) && *endptr != '_') | |
1004 | { | |
1005 | *error = string_sprintf("invalid character \"%c\" in variable name " | |
1006 | "in ACL modifier \"set %s\"", *endptr, s); | |
1007 | return NULL; | |
1008 | } | |
1009 | endptr++; | |
1010 | } | |
1011 | ||
1012 | cond->u.varname = string_copyn(s + 4, endptr - s - 4); | |
1013 | s = endptr; | |
1014 | while (isspace(*s)) s++; | |
1015 | } | |
1016 | ||
1017 | /* For "set", we are now positioned for the data. For the others, only | |
1018 | "endpass" has no data */ | |
1019 | ||
1020 | if (c != ACLC_ENDPASS) | |
1021 | { | |
1022 | if (*s++ != '=') | |
1023 | { | |
1024 | *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name, | |
1025 | cond_modifiers[c]? US"modifier" : US"condition"); | |
1026 | return NULL; | |
1027 | } | |
1028 | while (isspace(*s)) s++; | |
1029 | cond->arg = string_copy(s); | |
1030 | } | |
1031 | } | |
1032 | ||
1033 | return yield; | |
1034 | } | |
1035 | ||
1036 | ||
1037 | ||
1038 | /************************************************* | |
1039 | * Set up added header line(s) * | |
1040 | *************************************************/ | |
1041 | ||
1042 | /* This function is called by the add_header modifier, and also from acl_warn() | |
1043 | to implement the now-deprecated way of adding header lines using "message" on a | |
1044 | "warn" verb. The argument is treated as a sequence of header lines which are | |
1045 | added to a chain, provided there isn't an identical one already there. | |
1046 | ||
1047 | Argument: string of header lines | |
1048 | Returns: nothing | |
1049 | */ | |
1050 | ||
1051 | static void | |
1052 | setup_header(uschar *hstring) | |
1053 | { | |
1054 | uschar *p, *q; | |
1055 | int hlen = Ustrlen(hstring); | |
1056 | ||
1057 | /* Ignore any leading newlines */ | |
1058 | while (*hstring == '\n') hstring++, hlen--; | |
1059 | ||
1060 | /* An empty string does nothing; ensure exactly one final newline. */ | |
1061 | if (hlen <= 0) return; | |
1062 | if (hstring[--hlen] != '\n') hstring = string_sprintf("%s\n", hstring); | |
1063 | else while(hstring[--hlen] == '\n') hstring[hlen+1] = '\0'; | |
1064 | ||
1065 | /* Loop for multiple header lines, taking care about continuations */ | |
1066 | ||
1067 | for (p = q = hstring; *p != 0; ) | |
1068 | { | |
1069 | uschar *s; | |
1070 | int newtype = htype_add_bot; | |
1071 | header_line **hptr = &acl_added_headers; | |
1072 | ||
1073 | /* Find next header line within the string */ | |
1074 | ||
1075 | for (;;) | |
1076 | { | |
1077 | q = Ustrchr(q, '\n'); | |
1078 | if (*(++q) != ' ' && *q != '\t') break; | |
1079 | } | |
1080 | ||
1081 | /* If the line starts with a colon, interpret the instruction for where to | |
1082 | add it. This temporarily sets up a new type. */ | |
1083 | ||
1084 | if (*p == ':') | |
1085 | { | |
1086 | if (strncmpic(p, US":after_received:", 16) == 0) | |
1087 | { | |
1088 | newtype = htype_add_rec; | |
1089 | p += 16; | |
1090 | } | |
1091 | else if (strncmpic(p, US":at_start_rfc:", 14) == 0) | |
1092 | { | |
1093 | newtype = htype_add_rfc; | |
1094 | p += 14; | |
1095 | } | |
1096 | else if (strncmpic(p, US":at_start:", 10) == 0) | |
1097 | { | |
1098 | newtype = htype_add_top; | |
1099 | p += 10; | |
1100 | } | |
1101 | else if (strncmpic(p, US":at_end:", 8) == 0) | |
1102 | { | |
1103 | newtype = htype_add_bot; | |
1104 | p += 8; | |
1105 | } | |
1106 | while (*p == ' ' || *p == '\t') p++; | |
1107 | } | |
1108 | ||
1109 | /* See if this line starts with a header name, and if not, add X-ACL-Warn: | |
1110 | to the front of it. */ | |
1111 | ||
1112 | for (s = p; s < q - 1; s++) | |
1113 | { | |
1114 | if (*s == ':' || !isgraph(*s)) break; | |
1115 | } | |
1116 | ||
1117 | s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", (int) (q - p), p); | |
1118 | hlen = Ustrlen(s); | |
1119 | ||
1120 | /* See if this line has already been added */ | |
1121 | ||
1122 | while (*hptr != NULL) | |
1123 | { | |
1124 | if (Ustrncmp((*hptr)->text, s, hlen) == 0) break; | |
1125 | hptr = &((*hptr)->next); | |
1126 | } | |
1127 | ||
1128 | /* Add if not previously present */ | |
1129 | ||
1130 | if (*hptr == NULL) | |
1131 | { | |
1132 | header_line *h = store_get(sizeof(header_line)); | |
1133 | h->text = s; | |
1134 | h->next = NULL; | |
1135 | h->type = newtype; | |
1136 | h->slen = hlen; | |
1137 | *hptr = h; | |
1138 | hptr = &(h->next); | |
1139 | } | |
1140 | ||
1141 | /* Advance for next header line within the string */ | |
1142 | ||
1143 | p = q; | |
1144 | } | |
1145 | } | |
1146 | ||
1147 | ||
1148 | ||
1149 | /************************************************* | |
1150 | * List the added header lines * | |
1151 | *************************************************/ | |
1152 | uschar * | |
1153 | fn_hdrs_added(void) | |
1154 | { | |
1155 | uschar * ret = NULL; | |
1156 | header_line * h = acl_added_headers; | |
1157 | uschar * s; | |
1158 | uschar * cp; | |
1159 | int size = 0; | |
1160 | int ptr = 0; | |
1161 | ||
1162 | if (!h) return NULL; | |
1163 | ||
1164 | do | |
1165 | { | |
1166 | s = h->text; | |
1167 | while ((cp = Ustrchr(s, '\n')) != NULL) | |
1168 | { | |
1169 | if (cp[1] == '\0') break; | |
1170 | ||
1171 | /* contains embedded newline; needs doubling */ | |
1172 | ret = string_cat(ret, &size, &ptr, s, cp-s+1); | |
1173 | ret = string_cat(ret, &size, &ptr, US"\n", 1); | |
1174 | s = cp+1; | |
1175 | } | |
1176 | /* last bit of header */ | |
1177 | ||
1178 | ret = string_cat(ret, &size, &ptr, s, cp-s+1); /* newline-sep list */ | |
1179 | } | |
1180 | while((h = h->next)); | |
1181 | ||
1182 | ret[ptr-1] = '\0'; /* overwrite last newline */ | |
1183 | return ret; | |
1184 | } | |
1185 | ||
1186 | ||
1187 | /************************************************* | |
1188 | * Set up removed header line(s) * | |
1189 | *************************************************/ | |
1190 | ||
1191 | /* This function is called by the remove_header modifier. The argument is | |
1192 | treated as a sequence of header names which are added to a colon separated | |
1193 | list, provided there isn't an identical one already there. | |
1194 | ||
1195 | Argument: string of header names | |
1196 | Returns: nothing | |
1197 | */ | |
1198 | ||
1199 | static void | |
1200 | setup_remove_header(uschar *hnames) | |
1201 | { | |
1202 | if (*hnames != 0) | |
1203 | { | |
1204 | if (acl_removed_headers == NULL) | |
1205 | acl_removed_headers = hnames; | |
1206 | else | |
1207 | acl_removed_headers = string_sprintf("%s : %s", acl_removed_headers, hnames); | |
1208 | } | |
1209 | } | |
1210 | ||
1211 | ||
1212 | ||
1213 | /************************************************* | |
1214 | * Handle warnings * | |
1215 | *************************************************/ | |
1216 | ||
1217 | /* This function is called when a WARN verb's conditions are true. It adds to | |
1218 | the message's headers, and/or writes information to the log. In each case, this | |
1219 | only happens once (per message for headers, per connection for log). | |
1220 | ||
1221 | ** NOTE: The header adding action using the "message" setting is historic, and | |
1222 | its use is now deprecated. The new add_header modifier should be used instead. | |
1223 | ||
1224 | Arguments: | |
1225 | where ACL_WHERE_xxxx indicating which ACL this is | |
1226 | user_message message for adding to headers | |
1227 | log_message message for logging, if different | |
1228 | ||
1229 | Returns: nothing | |
1230 | */ | |
1231 | ||
1232 | static void | |
1233 | acl_warn(int where, uschar *user_message, uschar *log_message) | |
1234 | { | |
1235 | if (log_message != NULL && log_message != user_message) | |
1236 | { | |
1237 | uschar *text; | |
1238 | string_item *logged; | |
1239 | ||
1240 | text = string_sprintf("%s Warning: %s", host_and_ident(TRUE), | |
1241 | string_printing(log_message)); | |
1242 | ||
1243 | /* If a sender verification has failed, and the log message is "sender verify | |
1244 | failed", add the failure message. */ | |
1245 | ||
1246 | if (sender_verified_failed != NULL && | |
1247 | sender_verified_failed->message != NULL && | |
1248 | strcmpic(log_message, US"sender verify failed") == 0) | |
1249 | text = string_sprintf("%s: %s", text, sender_verified_failed->message); | |
1250 | ||
1251 | /* Search previously logged warnings. They are kept in malloc | |
1252 | store so they can be freed at the start of a new message. */ | |
1253 | ||
1254 | for (logged = acl_warn_logged; logged != NULL; logged = logged->next) | |
1255 | if (Ustrcmp(logged->text, text) == 0) break; | |
1256 | ||
1257 | if (logged == NULL) | |
1258 | { | |
1259 | int length = Ustrlen(text) + 1; | |
1260 | log_write(0, LOG_MAIN, "%s", text); | |
1261 | logged = store_malloc(sizeof(string_item) + length); | |
1262 | logged->text = (uschar *)logged + sizeof(string_item); | |
1263 | memcpy(logged->text, text, length); | |
1264 | logged->next = acl_warn_logged; | |
1265 | acl_warn_logged = logged; | |
1266 | } | |
1267 | } | |
1268 | ||
1269 | /* If there's no user message, we are done. */ | |
1270 | ||
1271 | if (user_message == NULL) return; | |
1272 | ||
1273 | /* If this isn't a message ACL, we can't do anything with a user message. | |
1274 | Log an error. */ | |
1275 | ||
1276 | if (where > ACL_WHERE_NOTSMTP) | |
1277 | { | |
1278 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting " | |
1279 | "found in a non-message (%s) ACL: cannot specify header lines here: " | |
1280 | "message ignored", acl_wherenames[where]); | |
1281 | return; | |
1282 | } | |
1283 | ||
1284 | /* The code for setting up header lines is now abstracted into a separate | |
1285 | function so that it can be used for the add_header modifier as well. */ | |
1286 | ||
1287 | setup_header(user_message); | |
1288 | } | |
1289 | ||
1290 | ||
1291 | ||
1292 | /************************************************* | |
1293 | * Verify and check reverse DNS * | |
1294 | *************************************************/ | |
1295 | ||
1296 | /* Called from acl_verify() below. We look up the host name(s) of the client IP | |
1297 | address if this has not yet been done. The host_name_lookup() function checks | |
1298 | that one of these names resolves to an address list that contains the client IP | |
1299 | address, so we don't actually have to do the check here. | |
1300 | ||
1301 | Arguments: | |
1302 | user_msgptr pointer for user message | |
1303 | log_msgptr pointer for log message | |
1304 | ||
1305 | Returns: OK verification condition succeeded | |
1306 | FAIL verification failed | |
1307 | DEFER there was a problem verifying | |
1308 | */ | |
1309 | ||
1310 | static int | |
1311 | acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr) | |
1312 | { | |
1313 | int rc; | |
1314 | ||
1315 | user_msgptr = user_msgptr; /* stop compiler warning */ | |
1316 | ||
1317 | /* Previous success */ | |
1318 | ||
1319 | if (sender_host_name != NULL) return OK; | |
1320 | ||
1321 | /* Previous failure */ | |
1322 | ||
1323 | if (host_lookup_failed) | |
1324 | { | |
1325 | *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg); | |
1326 | return FAIL; | |
1327 | } | |
1328 | ||
1329 | /* Need to do a lookup */ | |
1330 | ||
1331 | HDEBUG(D_acl) | |
1332 | debug_printf("looking up host name to force name/address consistency check\n"); | |
1333 | ||
1334 | if ((rc = host_name_lookup()) != OK) | |
1335 | { | |
1336 | *log_msgptr = (rc == DEFER)? | |
1337 | US"host lookup deferred for reverse lookup check" | |
1338 | : | |
1339 | string_sprintf("host lookup failed for reverse lookup check%s", | |
1340 | host_lookup_msg); | |
1341 | return rc; /* DEFER or FAIL */ | |
1342 | } | |
1343 | ||
1344 | host_build_sender_fullhost(); | |
1345 | return OK; | |
1346 | } | |
1347 | ||
1348 | ||
1349 | ||
1350 | /************************************************* | |
1351 | * Check client IP address matches CSA target * | |
1352 | *************************************************/ | |
1353 | ||
1354 | /* Called from acl_verify_csa() below. This routine scans a section of a DNS | |
1355 | response for address records belonging to the CSA target hostname. The section | |
1356 | is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS. | |
1357 | If one of the addresses matches the client's IP address, then the client is | |
1358 | authorized by CSA. If there are target IP addresses but none of them match | |
1359 | then the client is using an unauthorized IP address. If there are no target IP | |
1360 | addresses then the client cannot be using an authorized IP address. (This is | |
1361 | an odd configuration - why didn't the SRV record have a weight of 1 instead?) | |
1362 | ||
1363 | Arguments: | |
1364 | dnsa the DNS answer block | |
1365 | dnss a DNS scan block for us to use | |
1366 | reset option specifing what portion to scan, as described above | |
1367 | target the target hostname to use for matching RR names | |
1368 | ||
1369 | Returns: CSA_OK successfully authorized | |
1370 | CSA_FAIL_MISMATCH addresses found but none matched | |
1371 | CSA_FAIL_NOADDR no target addresses found | |
1372 | */ | |
1373 | ||
1374 | static int | |
1375 | acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset, | |
1376 | uschar *target) | |
1377 | { | |
1378 | dns_record *rr; | |
1379 | dns_address *da; | |
1380 | ||
1381 | BOOL target_found = FALSE; | |
1382 | ||
1383 | for (rr = dns_next_rr(dnsa, dnss, reset); | |
1384 | rr != NULL; | |
1385 | rr = dns_next_rr(dnsa, dnss, RESET_NEXT)) | |
1386 | { | |
1387 | /* Check this is an address RR for the target hostname. */ | |
1388 | ||
1389 | if (rr->type != T_A | |
1390 | #if HAVE_IPV6 | |
1391 | && rr->type != T_AAAA | |
1392 | #ifdef SUPPORT_A6 | |
1393 | && rr->type != T_A6 | |
1394 | #endif | |
1395 | #endif | |
1396 | ) continue; | |
1397 | ||
1398 | if (strcmpic(target, rr->name) != 0) continue; | |
1399 | ||
1400 | target_found = TRUE; | |
1401 | ||
1402 | /* Turn the target address RR into a list of textual IP addresses and scan | |
1403 | the list. There may be more than one if it is an A6 RR. */ | |
1404 | ||
1405 | for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next) | |
1406 | { | |
1407 | /* If the client IP address matches the target IP address, it's good! */ | |
1408 | ||
1409 | DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address); | |
1410 | ||
1411 | if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK; | |
1412 | } | |
1413 | } | |
1414 | ||
1415 | /* If we found some target addresses but none of them matched, the client is | |
1416 | using an unauthorized IP address, otherwise the target has no authorized IP | |
1417 | addresses. */ | |
1418 | ||
1419 | if (target_found) return CSA_FAIL_MISMATCH; | |
1420 | else return CSA_FAIL_NOADDR; | |
1421 | } | |
1422 | ||
1423 | ||
1424 | ||
1425 | /************************************************* | |
1426 | * Verify Client SMTP Authorization * | |
1427 | *************************************************/ | |
1428 | ||
1429 | /* Called from acl_verify() below. This routine calls dns_lookup_special() | |
1430 | to find the CSA SRV record corresponding to the domain argument, or | |
1431 | $sender_helo_name if no argument is provided. It then checks that the | |
1432 | client is authorized, and that its IP address corresponds to the SRV | |
1433 | target's address by calling acl_verify_csa_address() above. The address | |
1434 | should have been returned in the DNS response's ADDITIONAL section, but if | |
1435 | not we perform another DNS lookup to get it. | |
1436 | ||
1437 | Arguments: | |
1438 | domain pointer to optional parameter following verify = csa | |
1439 | ||
1440 | Returns: CSA_UNKNOWN no valid CSA record found | |
1441 | CSA_OK successfully authorized | |
1442 | CSA_FAIL_* client is definitely not authorized | |
1443 | CSA_DEFER_* there was a DNS problem | |
1444 | */ | |
1445 | ||
1446 | static int | |
1447 | acl_verify_csa(uschar *domain) | |
1448 | { | |
1449 | tree_node *t; | |
1450 | uschar *found, *p; | |
1451 | int priority, weight, port; | |
1452 | dns_answer dnsa; | |
1453 | dns_scan dnss; | |
1454 | dns_record *rr; | |
1455 | int rc, type; | |
1456 | uschar target[256]; | |
1457 | ||
1458 | /* Work out the domain we are using for the CSA lookup. The default is the | |
1459 | client's HELO domain. If the client has not said HELO, use its IP address | |
1460 | instead. If it's a local client (exim -bs), CSA isn't applicable. */ | |
1461 | ||
1462 | while (isspace(*domain) && *domain != '\0') ++domain; | |
1463 | if (*domain == '\0') domain = sender_helo_name; | |
1464 | if (domain == NULL) domain = sender_host_address; | |
1465 | if (sender_host_address == NULL) return CSA_UNKNOWN; | |
1466 | ||
1467 | /* If we have an address literal, strip off the framing ready for turning it | |
1468 | into a domain. The framing consists of matched square brackets possibly | |
1469 | containing a keyword and a colon before the actual IP address. */ | |
1470 | ||
1471 | if (domain[0] == '[') | |
1472 | { | |
1473 | uschar *start = Ustrchr(domain, ':'); | |
1474 | if (start == NULL) start = domain; | |
1475 | domain = string_copyn(start + 1, Ustrlen(start) - 2); | |
1476 | } | |
1477 | ||
1478 | /* Turn domains that look like bare IP addresses into domains in the reverse | |
1479 | DNS. This code also deals with address literals and $sender_host_address. It's | |
1480 | not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as | |
1481 | address literals, but it's probably the most friendly thing to do. This is an | |
1482 | extension to CSA, so we allow it to be turned off for proper conformance. */ | |
1483 | ||
1484 | if (string_is_ip_address(domain, NULL) != 0) | |
1485 | { | |
1486 | if (!dns_csa_use_reverse) return CSA_UNKNOWN; | |
1487 | dns_build_reverse(domain, target); | |
1488 | domain = target; | |
1489 | } | |
1490 | ||
1491 | /* Find out if we've already done the CSA check for this domain. If we have, | |
1492 | return the same result again. Otherwise build a new cached result structure | |
1493 | for this domain. The name is filled in now, and the value is filled in when | |
1494 | we return from this function. */ | |
1495 | ||
1496 | t = tree_search(csa_cache, domain); | |
1497 | if (t != NULL) return t->data.val; | |
1498 | ||
1499 | t = store_get_perm(sizeof(tree_node) + Ustrlen(domain)); | |
1500 | Ustrcpy(t->name, domain); | |
1501 | (void)tree_insertnode(&csa_cache, t); | |
1502 | ||
1503 | /* Now we are ready to do the actual DNS lookup(s). */ | |
1504 | ||
1505 | found = domain; | |
1506 | switch (dns_special_lookup(&dnsa, domain, T_CSA, &found)) | |
1507 | { | |
1508 | /* If something bad happened (most commonly DNS_AGAIN), defer. */ | |
1509 | ||
1510 | default: | |
1511 | return t->data.val = CSA_DEFER_SRV; | |
1512 | ||
1513 | /* If we found nothing, the client's authorization is unknown. */ | |
1514 | ||
1515 | case DNS_NOMATCH: | |
1516 | case DNS_NODATA: | |
1517 | return t->data.val = CSA_UNKNOWN; | |
1518 | ||
1519 | /* We got something! Go on to look at the reply in more detail. */ | |
1520 | ||
1521 | case DNS_SUCCEED: | |
1522 | break; | |
1523 | } | |
1524 | ||
1525 | /* Scan the reply for well-formed CSA SRV records. */ | |
1526 | ||
1527 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); | |
1528 | rr != NULL; | |
1529 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) | |
1530 | { | |
1531 | if (rr->type != T_SRV) continue; | |
1532 | ||
1533 | /* Extract the numerical SRV fields (p is incremented) */ | |
1534 | ||
1535 | p = rr->data; | |
1536 | GETSHORT(priority, p); | |
1537 | GETSHORT(weight, p); | |
1538 | GETSHORT(port, p); | |
1539 | ||
1540 | DEBUG(D_acl) | |
1541 | debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port); | |
1542 | ||
1543 | /* Check the CSA version number */ | |
1544 | ||
1545 | if (priority != 1) continue; | |
1546 | ||
1547 | /* If the domain does not have a CSA SRV record of its own (i.e. the domain | |
1548 | found by dns_special_lookup() is a parent of the one we asked for), we check | |
1549 | the subdomain assertions in the port field. At the moment there's only one | |
1550 | assertion: legitimate SMTP clients are all explicitly authorized with CSA | |
1551 | SRV records of their own. */ | |
1552 | ||
1553 | if (found != domain) | |
1554 | { | |
1555 | if (port & 1) | |
1556 | return t->data.val = CSA_FAIL_EXPLICIT; | |
1557 | else | |
1558 | return t->data.val = CSA_UNKNOWN; | |
1559 | } | |
1560 | ||
1561 | /* This CSA SRV record refers directly to our domain, so we check the value | |
1562 | in the weight field to work out the domain's authorization. 0 and 1 are | |
1563 | unauthorized; 3 means the client is authorized but we can't check the IP | |
1564 | address in order to authenticate it, so we treat it as unknown; values | |
1565 | greater than 3 are undefined. */ | |
1566 | ||
1567 | if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN; | |
1568 | ||
1569 | if (weight > 2) continue; | |
1570 | ||
1571 | /* Weight == 2, which means the domain is authorized. We must check that the | |
1572 | client's IP address is listed as one of the SRV target addresses. Save the | |
1573 | target hostname then break to scan the additional data for its addresses. */ | |
1574 | ||
1575 | (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p, | |
1576 | (DN_EXPAND_ARG4_TYPE)target, sizeof(target)); | |
1577 | ||
1578 | DEBUG(D_acl) debug_printf("CSA target is %s\n", target); | |
1579 | ||
1580 | break; | |
1581 | } | |
1582 | ||
1583 | /* If we didn't break the loop then no appropriate records were found. */ | |
1584 | ||
1585 | if (rr == NULL) return t->data.val = CSA_UNKNOWN; | |
1586 | ||
1587 | /* Do not check addresses if the target is ".", in accordance with RFC 2782. | |
1588 | A target of "." indicates there are no valid addresses, so the client cannot | |
1589 | be authorized. (This is an odd configuration because weight=2 target=. is | |
1590 | equivalent to weight=1, but we check for it in order to keep load off the | |
1591 | root name servers.) Note that dn_expand() turns "." into "". */ | |
1592 | ||
1593 | if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR; | |
1594 | ||
1595 | /* Scan the additional section of the CSA SRV reply for addresses belonging | |
1596 | to the target. If the name server didn't return any additional data (e.g. | |
1597 | because it does not fully support SRV records), we need to do another lookup | |
1598 | to obtain the target addresses; otherwise we have a definitive result. */ | |
1599 | ||
1600 | rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target); | |
1601 | if (rc != CSA_FAIL_NOADDR) return t->data.val = rc; | |
1602 | ||
1603 | /* The DNS lookup type corresponds to the IP version used by the client. */ | |
1604 | ||
1605 | #if HAVE_IPV6 | |
1606 | if (Ustrchr(sender_host_address, ':') != NULL) | |
1607 | type = T_AAAA; | |
1608 | else | |
1609 | #endif /* HAVE_IPV6 */ | |
1610 | type = T_A; | |
1611 | ||
1612 | ||
1613 | #if HAVE_IPV6 && defined(SUPPORT_A6) | |
1614 | DNS_LOOKUP_AGAIN: | |
1615 | #endif | |
1616 | ||
1617 | lookup_dnssec_authenticated = NULL; | |
1618 | switch (dns_lookup(&dnsa, target, type, NULL)) | |
1619 | { | |
1620 | /* If something bad happened (most commonly DNS_AGAIN), defer. */ | |
1621 | ||
1622 | default: | |
1623 | return t->data.val = CSA_DEFER_ADDR; | |
1624 | ||
1625 | /* If the query succeeded, scan the addresses and return the result. */ | |
1626 | ||
1627 | case DNS_SUCCEED: | |
1628 | rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target); | |
1629 | if (rc != CSA_FAIL_NOADDR) return t->data.val = rc; | |
1630 | /* else fall through */ | |
1631 | ||
1632 | /* If the target has no IP addresses, the client cannot have an authorized | |
1633 | IP address. However, if the target site uses A6 records (not AAAA records) | |
1634 | we have to do yet another lookup in order to check them. */ | |
1635 | ||
1636 | case DNS_NOMATCH: | |
1637 | case DNS_NODATA: | |
1638 | ||
1639 | #if HAVE_IPV6 && defined(SUPPORT_A6) | |
1640 | if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; } | |
1641 | #endif | |
1642 | ||
1643 | return t->data.val = CSA_FAIL_NOADDR; | |
1644 | } | |
1645 | } | |
1646 | ||
1647 | ||
1648 | ||
1649 | /************************************************* | |
1650 | * Handle verification (address & other) * | |
1651 | *************************************************/ | |
1652 | ||
1653 | enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX, | |
1654 | VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT, | |
1655 | VERIFY_HDR_NAMES_ASCII | |
1656 | }; | |
1657 | typedef struct { | |
1658 | uschar * name; | |
1659 | int value; | |
1660 | unsigned where_allowed; /* bitmap */ | |
1661 | BOOL no_options; /* Never has /option(s) following */ | |
1662 | unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */ | |
1663 | } verify_type_t; | |
1664 | static verify_type_t verify_type_list[] = { | |
1665 | { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, ~0, TRUE, 0 }, | |
1666 | { US"certificate", VERIFY_CERT, ~0, TRUE, 0 }, | |
1667 | { US"helo", VERIFY_HELO, ~0, TRUE, 0 }, | |
1668 | { US"csa", VERIFY_CSA, ~0, FALSE, 0 }, | |
1669 | { US"header_syntax", VERIFY_HDR_SYNTAX, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }, | |
1670 | { US"not_blind", VERIFY_NOT_BLIND, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 }, | |
1671 | { US"header_sender", VERIFY_HDR_SNDR, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), FALSE, 0 }, | |
1672 | { US"sender", VERIFY_SNDR, (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT) | |
1673 | |(1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), | |
1674 | FALSE, 6 }, | |
1675 | { US"recipient", VERIFY_RCPT, (1<<ACL_WHERE_RCPT), FALSE, 0 }, | |
1676 | { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), TRUE, 0 } | |
1677 | }; | |
1678 | ||
1679 | ||
1680 | enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER, | |
1681 | CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER, | |
1682 | CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT, | |
1683 | CALLOUT_TIME | |
1684 | }; | |
1685 | typedef struct { | |
1686 | uschar * name; | |
1687 | int value; | |
1688 | int flag; | |
1689 | BOOL has_option; /* Has =option(s) following */ | |
1690 | BOOL timeval; /* Has a time value */ | |
1691 | } callout_opt_t; | |
1692 | static callout_opt_t callout_opt_list[] = { | |
1693 | { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE }, | |
1694 | { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE }, | |
1695 | { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE }, | |
1696 | { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE }, | |
1697 | { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE }, | |
1698 | { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE }, | |
1699 | { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE }, | |
1700 | { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE }, | |
1701 | { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE }, | |
1702 | { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE }, | |
1703 | { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE }, | |
1704 | { NULL, CALLOUT_TIME, 0, FALSE, TRUE } | |
1705 | }; | |
1706 | ||
1707 | ||
1708 | ||
1709 | /* This function implements the "verify" condition. It is called when | |
1710 | encountered in any ACL, because some tests are almost always permitted. Some | |
1711 | just don't make sense, and always fail (for example, an attempt to test a host | |
1712 | lookup for a non-TCP/IP message). Others are restricted to certain ACLs. | |
1713 | ||
1714 | Arguments: | |
1715 | where where called from | |
1716 | addr the recipient address that the ACL is handling, or NULL | |
1717 | arg the argument of "verify" | |
1718 | user_msgptr pointer for user message | |
1719 | log_msgptr pointer for log message | |
1720 | basic_errno where to put verify errno | |
1721 | ||
1722 | Returns: OK verification condition succeeded | |
1723 | FAIL verification failed | |
1724 | DEFER there was a problem verifying | |
1725 | ERROR syntax error | |
1726 | */ | |
1727 | ||
1728 | static int | |
1729 | acl_verify(int where, address_item *addr, uschar *arg, | |
1730 | uschar **user_msgptr, uschar **log_msgptr, int *basic_errno) | |
1731 | { | |
1732 | int sep = '/'; | |
1733 | int callout = -1; | |
1734 | int callout_overall = -1; | |
1735 | int callout_connect = -1; | |
1736 | int verify_options = 0; | |
1737 | int rc; | |
1738 | BOOL verify_header_sender = FALSE; | |
1739 | BOOL defer_ok = FALSE; | |
1740 | BOOL callout_defer_ok = FALSE; | |
1741 | BOOL no_details = FALSE; | |
1742 | BOOL success_on_redirect = FALSE; | |
1743 | address_item *sender_vaddr = NULL; | |
1744 | uschar *verify_sender_address = NULL; | |
1745 | uschar *pm_mailfrom = NULL; | |
1746 | uschar *se_mailfrom = NULL; | |
1747 | ||
1748 | /* Some of the verify items have slash-separated options; some do not. Diagnose | |
1749 | an error if options are given for items that don't expect them. | |
1750 | */ | |
1751 | ||
1752 | uschar *slash = Ustrchr(arg, '/'); | |
1753 | uschar *list = arg; | |
1754 | uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size); | |
1755 | verify_type_t * vp; | |
1756 | ||
1757 | if (ss == NULL) goto BAD_VERIFY; | |
1758 | ||
1759 | /* Handle name/address consistency verification in a separate function. */ | |
1760 | ||
1761 | for (vp= verify_type_list; | |
1762 | (char *)vp < (char *)verify_type_list + sizeof(verify_type_list); | |
1763 | vp++ | |
1764 | ) | |
1765 | if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0 | |
1766 | : strcmpic (ss, vp->name) == 0) | |
1767 | break; | |
1768 | if ((char *)vp >= (char *)verify_type_list + sizeof(verify_type_list)) | |
1769 | goto BAD_VERIFY; | |
1770 | ||
1771 | if (vp->no_options && slash != NULL) | |
1772 | { | |
1773 | *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" " | |
1774 | "(this verify item has no options)", arg); | |
1775 | return ERROR; | |
1776 | } | |
1777 | if (!(vp->where_allowed & (1<<where))) | |
1778 | { | |
1779 | *log_msgptr = string_sprintf("cannot verify %s in ACL for %s", vp->name, acl_wherenames[where]); | |
1780 | return ERROR; | |
1781 | } | |
1782 | switch(vp->value) | |
1783 | { | |
1784 | case VERIFY_REV_HOST_LKUP: | |
1785 | if (sender_host_address == NULL) return OK; | |
1786 | return acl_verify_reverse(user_msgptr, log_msgptr); | |
1787 | ||
1788 | case VERIFY_CERT: | |
1789 | /* TLS certificate verification is done at STARTTLS time; here we just | |
1790 | test whether it was successful or not. (This is for optional verification; for | |
1791 | mandatory verification, the connection doesn't last this long.) */ | |
1792 | ||
1793 | if (tls_in.certificate_verified) return OK; | |
1794 | *user_msgptr = US"no verified certificate"; | |
1795 | return FAIL; | |
1796 | ||
1797 | case VERIFY_HELO: | |
1798 | /* We can test the result of optional HELO verification that might have | |
1799 | occurred earlier. If not, we can attempt the verification now. */ | |
1800 | ||
1801 | if (!helo_verified && !helo_verify_failed) smtp_verify_helo(); | |
1802 | return helo_verified? OK : FAIL; | |
1803 | ||
1804 | case VERIFY_CSA: | |
1805 | /* Do Client SMTP Authorization checks in a separate function, and turn the | |
1806 | result code into user-friendly strings. */ | |
1807 | ||
1808 | rc = acl_verify_csa(list); | |
1809 | *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s", | |
1810 | csa_reason_string[rc]); | |
1811 | csa_status = csa_status_string[rc]; | |
1812 | DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status); | |
1813 | return csa_return_code[rc]; | |
1814 | ||
1815 | case VERIFY_HDR_SYNTAX: | |
1816 | /* Check that all relevant header lines have the correct syntax. If there is | |
1817 | a syntax error, we return details of the error to the sender if configured to | |
1818 | send out full details. (But a "message" setting on the ACL can override, as | |
1819 | always). */ | |
1820 | ||
1821 | rc = verify_check_headers(log_msgptr); | |
1822 | if (rc != OK && smtp_return_error_details && *log_msgptr != NULL) | |
1823 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); | |
1824 | return rc; | |
1825 | ||
1826 | case VERIFY_HDR_NAMES_ASCII: | |
1827 | /* Check that all header names are true 7 bit strings | |
1828 | See RFC 5322, 2.2. and RFC 6532, 3. */ | |
1829 | ||
1830 | rc = verify_check_header_names_ascii(log_msgptr); | |
1831 | if (rc != OK && smtp_return_error_details && *log_msgptr != NULL) | |
1832 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); | |
1833 | return rc; | |
1834 | ||
1835 | case VERIFY_NOT_BLIND: | |
1836 | /* Check that no recipient of this message is "blind", that is, every envelope | |
1837 | recipient must be mentioned in either To: or Cc:. */ | |
1838 | ||
1839 | rc = verify_check_notblind(); | |
1840 | if (rc != OK) | |
1841 | { | |
1842 | *log_msgptr = string_sprintf("bcc recipient detected"); | |
1843 | if (smtp_return_error_details) | |
1844 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); | |
1845 | } | |
1846 | return rc; | |
1847 | ||
1848 | /* The remaining verification tests check recipient and sender addresses, | |
1849 | either from the envelope or from the header. There are a number of | |
1850 | slash-separated options that are common to all of them. */ | |
1851 | ||
1852 | case VERIFY_HDR_SNDR: | |
1853 | verify_header_sender = TRUE; | |
1854 | break; | |
1855 | ||
1856 | case VERIFY_SNDR: | |
1857 | /* In the case of a sender, this can optionally be followed by an address to use | |
1858 | in place of the actual sender (rare special-case requirement). */ | |
1859 | { | |
1860 | uschar *s = ss + 6; | |
1861 | if (*s == 0) | |
1862 | verify_sender_address = sender_address; | |
1863 | else | |
1864 | { | |
1865 | while (isspace(*s)) s++; | |
1866 | if (*s++ != '=') goto BAD_VERIFY; | |
1867 | while (isspace(*s)) s++; | |
1868 | verify_sender_address = string_copy(s); | |
1869 | } | |
1870 | } | |
1871 | break; | |
1872 | ||
1873 | case VERIFY_RCPT: | |
1874 | break; | |
1875 | } | |
1876 | ||
1877 | ||
1878 | ||
1879 | /* Remaining items are optional; they apply to sender and recipient | |
1880 | verification, including "header sender" verification. */ | |
1881 | ||
1882 | while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)) | |
1883 | != NULL) | |
1884 | { | |
1885 | if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE; | |
1886 | else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE; | |
1887 | else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE; | |
1888 | ||
1889 | /* These two old options are left for backwards compatibility */ | |
1890 | ||
1891 | else if (strcmpic(ss, US"callout_defer_ok") == 0) | |
1892 | { | |
1893 | callout_defer_ok = TRUE; | |
1894 | if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT; | |
1895 | } | |
1896 | ||
1897 | else if (strcmpic(ss, US"check_postmaster") == 0) | |
1898 | { | |
1899 | pm_mailfrom = US""; | |
1900 | if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT; | |
1901 | } | |
1902 | ||
1903 | /* The callout option has a number of sub-options, comma separated */ | |
1904 | ||
1905 | else if (strncmpic(ss, US"callout", 7) == 0) | |
1906 | { | |
1907 | callout = CALLOUT_TIMEOUT_DEFAULT; | |
1908 | ss += 7; | |
1909 | if (*ss != 0) | |
1910 | { | |
1911 | while (isspace(*ss)) ss++; | |
1912 | if (*ss++ == '=') | |
1913 | { | |
1914 | int optsep = ','; | |
1915 | uschar *opt; | |
1916 | uschar buffer[256]; | |
1917 | while (isspace(*ss)) ss++; | |
1918 | ||
1919 | while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer))) | |
1920 | != NULL) | |
1921 | { | |
1922 | callout_opt_t * op; | |
1923 | double period = 1.0F; | |
1924 | ||
1925 | for (op= callout_opt_list; op->name; op++) | |
1926 | if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0) | |
1927 | break; | |
1928 | ||
1929 | verify_options |= op->flag; | |
1930 | if (op->has_option) | |
1931 | { | |
1932 | opt += Ustrlen(op->name); | |
1933 | while (isspace(*opt)) opt++; | |
1934 | if (*opt++ != '=') | |
1935 | { | |
1936 | *log_msgptr = string_sprintf("'=' expected after " | |
1937 | "\"%s\" in ACL verify condition \"%s\"", op->name, arg); | |
1938 | return ERROR; | |
1939 | } | |
1940 | while (isspace(*opt)) opt++; | |
1941 | } | |
1942 | if (op->timeval) | |
1943 | { | |
1944 | period = readconf_readtime(opt, 0, FALSE); | |
1945 | if (period < 0) | |
1946 | { | |
1947 | *log_msgptr = string_sprintf("bad time value in ACL condition " | |
1948 | "\"verify %s\"", arg); | |
1949 | return ERROR; | |
1950 | } | |
1951 | } | |
1952 | ||
1953 | switch(op->value) | |
1954 | { | |
1955 | case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break; | |
1956 | case CALLOUT_POSTMASTER: pm_mailfrom = US""; break; | |
1957 | case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break; | |
1958 | case CALLOUT_MAILFROM: | |
1959 | if (!verify_header_sender) | |
1960 | { | |
1961 | *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a " | |
1962 | "callout option only for verify=header_sender (detected in ACL " | |
1963 | "condition \"%s\")", arg); | |
1964 | return ERROR; | |
1965 | } | |
1966 | se_mailfrom = string_copy(opt); | |
1967 | break; | |
1968 | case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break; | |
1969 | case CALLOUT_MAXWAIT: callout_overall = period; break; | |
1970 | case CALLOUT_CONNECT: callout_connect = period; break; | |
1971 | case CALLOUT_TIME: callout = period; break; | |
1972 | } | |
1973 | } | |
1974 | } | |
1975 | else | |
1976 | { | |
1977 | *log_msgptr = string_sprintf("'=' expected after \"callout\" in " | |
1978 | "ACL condition \"%s\"", arg); | |
1979 | return ERROR; | |
1980 | } | |
1981 | } | |
1982 | } | |
1983 | ||
1984 | /* Option not recognized */ | |
1985 | ||
1986 | else | |
1987 | { | |
1988 | *log_msgptr = string_sprintf("unknown option \"%s\" in ACL " | |
1989 | "condition \"verify %s\"", ss, arg); | |
1990 | return ERROR; | |
1991 | } | |
1992 | } | |
1993 | ||
1994 | if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == | |
1995 | (vopt_callout_recipsender|vopt_callout_recippmaster)) | |
1996 | { | |
1997 | *log_msgptr = US"only one of use_sender and use_postmaster can be set " | |
1998 | "for a recipient callout"; | |
1999 | return ERROR; | |
2000 | } | |
2001 | ||
2002 | /* Handle sender-in-header verification. Default the user message to the log | |
2003 | message if giving out verification details. */ | |
2004 | ||
2005 | if (verify_header_sender) | |
2006 | { | |
2007 | int verrno; | |
2008 | rc = verify_check_header_address(user_msgptr, log_msgptr, callout, | |
2009 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options, | |
2010 | &verrno); | |
2011 | if (rc != OK) | |
2012 | { | |
2013 | *basic_errno = verrno; | |
2014 | if (smtp_return_error_details) | |
2015 | { | |
2016 | if (*user_msgptr == NULL && *log_msgptr != NULL) | |
2017 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); | |
2018 | if (rc == DEFER) acl_temp_details = TRUE; | |
2019 | } | |
2020 | } | |
2021 | } | |
2022 | ||
2023 | /* Handle a sender address. The default is to verify *the* sender address, but | |
2024 | optionally a different address can be given, for special requirements. If the | |
2025 | address is empty, we are dealing with a bounce message that has no sender, so | |
2026 | we cannot do any checking. If the real sender address gets rewritten during | |
2027 | verification (e.g. DNS widening), set the flag to stop it being rewritten again | |
2028 | during message reception. | |
2029 | ||
2030 | A list of verified "sender" addresses is kept to try to avoid doing to much | |
2031 | work repetitively when there are multiple recipients in a message and they all | |
2032 | require sender verification. However, when callouts are involved, it gets too | |
2033 | complicated because different recipients may require different callout options. | |
2034 | Therefore, we always do a full sender verify when any kind of callout is | |
2035 | specified. Caching elsewhere, for instance in the DNS resolver and in the | |
2036 | callout handling, should ensure that this is not terribly inefficient. */ | |
2037 | ||
2038 | else if (verify_sender_address != NULL) | |
2039 | { | |
2040 | if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) | |
2041 | != 0) | |
2042 | { | |
2043 | *log_msgptr = US"use_sender or use_postmaster cannot be used for a " | |
2044 | "sender verify callout"; | |
2045 | return ERROR; | |
2046 | } | |
2047 | ||
2048 | sender_vaddr = verify_checked_sender(verify_sender_address); | |
2049 | if (sender_vaddr != NULL && /* Previously checked */ | |
2050 | callout <= 0) /* No callout needed this time */ | |
2051 | { | |
2052 | /* If the "routed" flag is set, it means that routing worked before, so | |
2053 | this check can give OK (the saved return code value, if set, belongs to a | |
2054 | callout that was done previously). If the "routed" flag is not set, routing | |
2055 | must have failed, so we use the saved return code. */ | |
2056 | ||
2057 | if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else | |
2058 | { | |
2059 | rc = sender_vaddr->special_action; | |
2060 | *basic_errno = sender_vaddr->basic_errno; | |
2061 | } | |
2062 | HDEBUG(D_acl) debug_printf("using cached sender verify result\n"); | |
2063 | } | |
2064 | ||
2065 | /* Do a new verification, and cache the result. The cache is used to avoid | |
2066 | verifying the sender multiple times for multiple RCPTs when callouts are not | |
2067 | specified (see comments above). | |
2068 | ||
2069 | The cache is also used on failure to give details in response to the first | |
2070 | RCPT that gets bounced for this reason. However, this can be suppressed by | |
2071 | the no_details option, which sets the flag that says "this detail has already | |
2072 | been sent". The cache normally contains just one address, but there may be | |
2073 | more in esoteric circumstances. */ | |
2074 | ||
2075 | else | |
2076 | { | |
2077 | BOOL routed = TRUE; | |
2078 | uschar *save_address_data = deliver_address_data; | |
2079 | ||
2080 | sender_vaddr = deliver_make_addr(verify_sender_address, TRUE); | |
2081 | if (no_details) setflag(sender_vaddr, af_sverify_told); | |
2082 | if (verify_sender_address[0] != 0) | |
2083 | { | |
2084 | /* If this is the real sender address, save the unrewritten version | |
2085 | for use later in receive. Otherwise, set a flag so that rewriting the | |
2086 | sender in verify_address() does not update sender_address. */ | |
2087 | ||
2088 | if (verify_sender_address == sender_address) | |
2089 | sender_address_unrewritten = sender_address; | |
2090 | else | |
2091 | verify_options |= vopt_fake_sender; | |
2092 | ||
2093 | if (success_on_redirect) | |
2094 | verify_options |= vopt_success_on_redirect; | |
2095 | ||
2096 | /* The recipient, qualify, and expn options are never set in | |
2097 | verify_options. */ | |
2098 | ||
2099 | rc = verify_address(sender_vaddr, NULL, verify_options, callout, | |
2100 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed); | |
2101 | ||
2102 | HDEBUG(D_acl) debug_printf("----------- end verify ------------\n"); | |
2103 | ||
2104 | if (rc == OK) | |
2105 | { | |
2106 | if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0) | |
2107 | { | |
2108 | DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n", | |
2109 | verify_sender_address, sender_vaddr->address); | |
2110 | } | |
2111 | else | |
2112 | { | |
2113 | DEBUG(D_acl) debug_printf("sender %s verified ok\n", | |
2114 | verify_sender_address); | |
2115 | } | |
2116 | } | |
2117 | else *basic_errno = sender_vaddr->basic_errno; | |
2118 | } | |
2119 | else rc = OK; /* Null sender */ | |
2120 | ||
2121 | /* Cache the result code */ | |
2122 | ||
2123 | if (routed) setflag(sender_vaddr, af_verify_routed); | |
2124 | if (callout > 0) setflag(sender_vaddr, af_verify_callout); | |
2125 | sender_vaddr->special_action = rc; | |
2126 | sender_vaddr->next = sender_verified_list; | |
2127 | sender_verified_list = sender_vaddr; | |
2128 | ||
2129 | /* Restore the recipient address data, which might have been clobbered by | |
2130 | the sender verification. */ | |
2131 | ||
2132 | deliver_address_data = save_address_data; | |
2133 | } | |
2134 | ||
2135 | /* Put the sender address_data value into $sender_address_data */ | |
2136 | ||
2137 | sender_address_data = sender_vaddr->p.address_data; | |
2138 | } | |
2139 | ||
2140 | /* A recipient address just gets a straightforward verify; again we must handle | |
2141 | the DEFER overrides. */ | |
2142 | ||
2143 | else | |
2144 | { | |
2145 | address_item addr2; | |
2146 | ||
2147 | if (success_on_redirect) | |
2148 | verify_options |= vopt_success_on_redirect; | |
2149 | ||
2150 | /* We must use a copy of the address for verification, because it might | |
2151 | get rewritten. */ | |
2152 | ||
2153 | addr2 = *addr; | |
2154 | rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout, | |
2155 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL); | |
2156 | HDEBUG(D_acl) debug_printf("----------- end verify ------------\n"); | |
2157 | ||
2158 | *basic_errno = addr2.basic_errno; | |
2159 | *log_msgptr = addr2.message; | |
2160 | *user_msgptr = (addr2.user_message != NULL)? | |
2161 | addr2.user_message : addr2.message; | |
2162 | ||
2163 | /* Allow details for temporary error if the address is so flagged. */ | |
2164 | if (testflag((&addr2), af_pass_message)) acl_temp_details = TRUE; | |
2165 | ||
2166 | /* Make $address_data visible */ | |
2167 | deliver_address_data = addr2.p.address_data; | |
2168 | } | |
2169 | ||
2170 | /* We have a result from the relevant test. Handle defer overrides first. */ | |
2171 | ||
2172 | if (rc == DEFER && (defer_ok || | |
2173 | (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER))) | |
2174 | { | |
2175 | HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n", | |
2176 | defer_ok? "defer_ok" : "callout_defer_ok"); | |
2177 | rc = OK; | |
2178 | } | |
2179 | ||
2180 | /* If we've failed a sender, set up a recipient message, and point | |
2181 | sender_verified_failed to the address item that actually failed. */ | |
2182 | ||
2183 | if (rc != OK && verify_sender_address != NULL) | |
2184 | { | |
2185 | if (rc != DEFER) | |
2186 | { | |
2187 | *log_msgptr = *user_msgptr = US"Sender verify failed"; | |
2188 | } | |
2189 | else if (*basic_errno != ERRNO_CALLOUTDEFER) | |
2190 | { | |
2191 | *log_msgptr = *user_msgptr = US"Could not complete sender verify"; | |
2192 | } | |
2193 | else | |
2194 | { | |
2195 | *log_msgptr = US"Could not complete sender verify callout"; | |
2196 | *user_msgptr = smtp_return_error_details? sender_vaddr->user_message : | |
2197 | *log_msgptr; | |
2198 | } | |
2199 | ||
2200 | sender_verified_failed = sender_vaddr; | |
2201 | } | |
2202 | ||
2203 | /* Verifying an address messes up the values of $domain and $local_part, | |
2204 | so reset them before returning if this is a RCPT ACL. */ | |
2205 | ||
2206 | if (addr != NULL) | |
2207 | { | |
2208 | deliver_domain = addr->domain; | |
2209 | deliver_localpart = addr->local_part; | |
2210 | } | |
2211 | return rc; | |
2212 | ||
2213 | /* Syntax errors in the verify argument come here. */ | |
2214 | ||
2215 | BAD_VERIFY: | |
2216 | *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", " | |
2217 | "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" " | |
2218 | "or \"reverse_host_lookup\" at start of ACL condition " | |
2219 | "\"verify %s\"", arg); | |
2220 | return ERROR; | |
2221 | } | |
2222 | ||
2223 | ||
2224 | ||
2225 | ||
2226 | /************************************************* | |
2227 | * Check argument for control= modifier * | |
2228 | *************************************************/ | |
2229 | ||
2230 | /* Called from acl_check_condition() below | |
2231 | ||
2232 | Arguments: | |
2233 | arg the argument string for control= | |
2234 | pptr set to point to the terminating character | |
2235 | where which ACL we are in | |
2236 | log_msgptr for error messages | |
2237 | ||
2238 | Returns: CONTROL_xxx value | |
2239 | */ | |
2240 | ||
2241 | static int | |
2242 | decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr) | |
2243 | { | |
2244 | int len; | |
2245 | control_def *d; | |
2246 | ||
2247 | for (d = controls_list; | |
2248 | d < controls_list + sizeof(controls_list)/sizeof(control_def); | |
2249 | d++) | |
2250 | { | |
2251 | len = Ustrlen(d->name); | |
2252 | if (Ustrncmp(d->name, arg, len) == 0) break; | |
2253 | } | |
2254 | ||
2255 | if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) || | |
2256 | (arg[len] != 0 && (!d->has_option || arg[len] != '/'))) | |
2257 | { | |
2258 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); | |
2259 | return CONTROL_ERROR; | |
2260 | } | |
2261 | ||
2262 | *pptr = arg + len; | |
2263 | return d->value; | |
2264 | } | |
2265 | ||
2266 | ||
2267 | ||
2268 | ||
2269 | /************************************************* | |
2270 | * Return a ratelimit error * | |
2271 | *************************************************/ | |
2272 | ||
2273 | /* Called from acl_ratelimit() below | |
2274 | ||
2275 | Arguments: | |
2276 | log_msgptr for error messages | |
2277 | format format string | |
2278 | ... supplementary arguments | |
2279 | ss ratelimit option name | |
2280 | where ACL_WHERE_xxxx indicating which ACL this is | |
2281 | ||
2282 | Returns: ERROR | |
2283 | */ | |
2284 | ||
2285 | static int | |
2286 | ratelimit_error(uschar **log_msgptr, const char *format, ...) | |
2287 | { | |
2288 | va_list ap; | |
2289 | uschar buffer[STRING_SPRINTF_BUFFER_SIZE]; | |
2290 | va_start(ap, format); | |
2291 | if (!string_vformat(buffer, sizeof(buffer), format, ap)) | |
2292 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, | |
2293 | "string_sprintf expansion was longer than " SIZE_T_FMT, sizeof(buffer)); | |
2294 | va_end(ap); | |
2295 | *log_msgptr = string_sprintf( | |
2296 | "error in arguments to \"ratelimit\" condition: %s", buffer); | |
2297 | return ERROR; | |
2298 | } | |
2299 | ||
2300 | ||
2301 | ||
2302 | ||
2303 | /************************************************* | |
2304 | * Handle rate limiting * | |
2305 | *************************************************/ | |
2306 | ||
2307 | /* Called by acl_check_condition() below to calculate the result | |
2308 | of the ACL ratelimit condition. | |
2309 | ||
2310 | Note that the return value might be slightly unexpected: if the | |
2311 | sender's rate is above the limit then the result is OK. This is | |
2312 | similar to the dnslists condition, and is so that you can write | |
2313 | ACL clauses like: defer ratelimit = 15 / 1h | |
2314 | ||
2315 | Arguments: | |
2316 | arg the option string for ratelimit= | |
2317 | where ACL_WHERE_xxxx indicating which ACL this is | |
2318 | log_msgptr for error messages | |
2319 | ||
2320 | Returns: OK - Sender's rate is above limit | |
2321 | FAIL - Sender's rate is below limit | |
2322 | DEFER - Problem opening ratelimit database | |
2323 | ERROR - Syntax error in options. | |
2324 | */ | |
2325 | ||
2326 | static int | |
2327 | acl_ratelimit(uschar *arg, int where, uschar **log_msgptr) | |
2328 | { | |
2329 | double limit, period, count; | |
2330 | uschar *ss; | |
2331 | uschar *key = NULL; | |
2332 | uschar *unique = NULL; | |
2333 | int sep = '/'; | |
2334 | BOOL leaky = FALSE, strict = FALSE, readonly = FALSE; | |
2335 | BOOL noupdate = FALSE, badacl = FALSE; | |
2336 | int mode = RATE_PER_WHAT; | |
2337 | int old_pool, rc; | |
2338 | tree_node **anchor, *t; | |
2339 | open_db dbblock, *dbm; | |
2340 | int dbdb_size; | |
2341 | dbdata_ratelimit *dbd; | |
2342 | dbdata_ratelimit_unique *dbdb; | |
2343 | struct timeval tv; | |
2344 | ||
2345 | /* Parse the first two options and record their values in expansion | |
2346 | variables. These variables allow the configuration to have informative | |
2347 | error messages based on rate limits obtained from a table lookup. */ | |
2348 | ||
2349 | /* First is the maximum number of messages per period / maximum burst | |
2350 | size, which must be greater than or equal to zero. Zero is useful for | |
2351 | rate measurement as opposed to rate limiting. */ | |
2352 | ||
2353 | sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0); | |
2354 | if (sender_rate_limit == NULL) | |
2355 | limit = -1.0; | |
2356 | else | |
2357 | { | |
2358 | limit = Ustrtod(sender_rate_limit, &ss); | |
2359 | if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; } | |
2360 | else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; } | |
2361 | else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; } | |
2362 | } | |
2363 | if (limit < 0.0 || *ss != '\0') | |
2364 | return ratelimit_error(log_msgptr, | |
2365 | "\"%s\" is not a positive number", sender_rate_limit); | |
2366 | ||
2367 | /* Second is the rate measurement period / exponential smoothing time | |
2368 | constant. This must be strictly greater than zero, because zero leads to | |
2369 | run-time division errors. */ | |
2370 | ||
2371 | sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0); | |
2372 | if (sender_rate_period == NULL) period = -1.0; | |
2373 | else period = readconf_readtime(sender_rate_period, 0, FALSE); | |
2374 | if (period <= 0.0) | |
2375 | return ratelimit_error(log_msgptr, | |
2376 | "\"%s\" is not a time value", sender_rate_period); | |
2377 | ||
2378 | /* By default we are counting one of something, but the per_rcpt, | |
2379 | per_byte, and count options can change this. */ | |
2380 | ||
2381 | count = 1.0; | |
2382 | ||
2383 | /* Parse the other options. */ | |
2384 | ||
2385 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) | |
2386 | != NULL) | |
2387 | { | |
2388 | if (strcmpic(ss, US"leaky") == 0) leaky = TRUE; | |
2389 | else if (strcmpic(ss, US"strict") == 0) strict = TRUE; | |
2390 | else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE; | |
2391 | else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE; | |
2392 | else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD); | |
2393 | else if (strcmpic(ss, US"per_conn") == 0) | |
2394 | { | |
2395 | RATE_SET(mode, PER_CONN); | |
2396 | if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START) | |
2397 | badacl = TRUE; | |
2398 | } | |
2399 | else if (strcmpic(ss, US"per_mail") == 0) | |
2400 | { | |
2401 | RATE_SET(mode, PER_MAIL); | |
2402 | if (where > ACL_WHERE_NOTSMTP) badacl = TRUE; | |
2403 | } | |
2404 | else if (strcmpic(ss, US"per_rcpt") == 0) | |
2405 | { | |
2406 | /* If we are running in the RCPT ACL, then we'll count the recipients | |
2407 | one by one, but if we are running when we have accumulated the whole | |
2408 | list then we'll add them all in one batch. */ | |
2409 | if (where == ACL_WHERE_RCPT) | |
2410 | RATE_SET(mode, PER_RCPT); | |
2411 | else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP) | |
2412 | RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count; | |
2413 | else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP) | |
2414 | RATE_SET(mode, PER_RCPT), badacl = TRUE; | |
2415 | } | |
2416 | else if (strcmpic(ss, US"per_byte") == 0) | |
2417 | { | |
2418 | /* If we have not yet received the message data and there was no SIZE | |
2419 | declaration on the MAIL comand, then it's safe to just use a value of | |
2420 | zero and let the recorded rate decay as if nothing happened. */ | |
2421 | RATE_SET(mode, PER_MAIL); | |
2422 | if (where > ACL_WHERE_NOTSMTP) badacl = TRUE; | |
2423 | else count = message_size < 0 ? 0.0 : (double)message_size; | |
2424 | } | |
2425 | else if (strcmpic(ss, US"per_addr") == 0) | |
2426 | { | |
2427 | RATE_SET(mode, PER_RCPT); | |
2428 | if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*"; | |
2429 | else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain); | |
2430 | } | |
2431 | else if (strncmpic(ss, US"count=", 6) == 0) | |
2432 | { | |
2433 | uschar *e; | |
2434 | count = Ustrtod(ss+6, &e); | |
2435 | if (count < 0.0 || *e != '\0') | |
2436 | return ratelimit_error(log_msgptr, | |
2437 | "\"%s\" is not a positive number", ss); | |
2438 | } | |
2439 | else if (strncmpic(ss, US"unique=", 7) == 0) | |
2440 | unique = string_copy(ss + 7); | |
2441 | else if (key == NULL) | |
2442 | key = string_copy(ss); | |
2443 | else | |
2444 | key = string_sprintf("%s/%s", key, ss); | |
2445 | } | |
2446 | ||
2447 | /* Sanity check. When the badacl flag is set the update mode must either | |
2448 | be readonly (which is the default if it is omitted) or, for backwards | |
2449 | compatibility, a combination of noupdate and strict or leaky. */ | |
2450 | ||
2451 | if (mode == RATE_PER_CLASH) | |
2452 | return ratelimit_error(log_msgptr, "conflicting per_* options"); | |
2453 | if (leaky + strict + readonly > 1) | |
2454 | return ratelimit_error(log_msgptr, "conflicting update modes"); | |
2455 | if (badacl && (leaky || strict) && !noupdate) | |
2456 | return ratelimit_error(log_msgptr, | |
2457 | "\"%s\" must not have /leaky or /strict option in %s ACL", | |
2458 | ratelimit_option_string[mode], acl_wherenames[where]); | |
2459 | ||
2460 | /* Set the default values of any unset options. In readonly mode we | |
2461 | perform the rate computation without any increment so that its value | |
2462 | decays to eventually allow over-limit senders through. */ | |
2463 | ||
2464 | if (noupdate) readonly = TRUE, leaky = strict = FALSE; | |
2465 | if (badacl) readonly = TRUE; | |
2466 | if (readonly) count = 0.0; | |
2467 | if (!strict && !readonly) leaky = TRUE; | |
2468 | if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL; | |
2469 | ||
2470 | /* Create the lookup key. If there is no explicit key, use sender_host_address. | |
2471 | If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply | |
2472 | omit it. The smoothing constant (sender_rate_period) and the per_xxx options | |
2473 | are added to the key because they alter the meaning of the stored data. */ | |
2474 | ||
2475 | if (key == NULL) | |
2476 | key = (sender_host_address == NULL)? US"" : sender_host_address; | |
2477 | ||
2478 | key = string_sprintf("%s/%s/%s%s", | |
2479 | sender_rate_period, | |
2480 | ratelimit_option_string[mode], | |
2481 | unique == NULL ? "" : "unique/", | |
2482 | key); | |
2483 | ||
2484 | HDEBUG(D_acl) | |
2485 | debug_printf("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key); | |
2486 | ||
2487 | /* See if we have already computed the rate by looking in the relevant tree. | |
2488 | For per-connection rate limiting, store tree nodes and dbdata in the permanent | |
2489 | pool so that they survive across resets. In readonly mode we only remember the | |
2490 | result for the rest of this command in case a later command changes it. After | |
2491 | this bit of logic the code is independent of the per_* mode. */ | |
2492 | ||
2493 | old_pool = store_pool; | |
2494 | ||
2495 | if (readonly) | |
2496 | anchor = &ratelimiters_cmd; | |
2497 | else switch(mode) { | |
2498 | case RATE_PER_CONN: | |
2499 | anchor = &ratelimiters_conn; | |
2500 | store_pool = POOL_PERM; | |
2501 | break; | |
2502 | case RATE_PER_BYTE: | |
2503 | case RATE_PER_MAIL: | |
2504 | case RATE_PER_ALLRCPTS: | |
2505 | anchor = &ratelimiters_mail; | |
2506 | break; | |
2507 | case RATE_PER_ADDR: | |
2508 | case RATE_PER_CMD: | |
2509 | case RATE_PER_RCPT: | |
2510 | anchor = &ratelimiters_cmd; | |
2511 | break; | |
2512 | default: | |
2513 | anchor = NULL; /* silence an "unused" complaint */ | |
2514 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, | |
2515 | "internal ACL error: unknown ratelimit mode %d", mode); | |
2516 | break; | |
2517 | } | |
2518 | ||
2519 | t = tree_search(*anchor, key); | |
2520 | if (t != NULL) | |
2521 | { | |
2522 | dbd = t->data.ptr; | |
2523 | /* The following few lines duplicate some of the code below. */ | |
2524 | rc = (dbd->rate < limit)? FAIL : OK; | |
2525 | store_pool = old_pool; | |
2526 | sender_rate = string_sprintf("%.1f", dbd->rate); | |
2527 | HDEBUG(D_acl) | |
2528 | debug_printf("ratelimit found pre-computed rate %s\n", sender_rate); | |
2529 | return rc; | |
2530 | } | |
2531 | ||
2532 | /* We aren't using a pre-computed rate, so get a previously recorded rate | |
2533 | from the database, which will be updated and written back if required. */ | |
2534 | ||
2535 | dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE); | |
2536 | if (dbm == NULL) | |
2537 | { | |
2538 | store_pool = old_pool; | |
2539 | sender_rate = NULL; | |
2540 | HDEBUG(D_acl) debug_printf("ratelimit database not available\n"); | |
2541 | *log_msgptr = US"ratelimit database not available"; | |
2542 | return DEFER; | |
2543 | } | |
2544 | dbdb = dbfn_read_with_length(dbm, key, &dbdb_size); | |
2545 | dbd = NULL; | |
2546 | ||
2547 | gettimeofday(&tv, NULL); | |
2548 | ||
2549 | if (dbdb != NULL) | |
2550 | { | |
2551 | /* Locate the basic ratelimit block inside the DB data. */ | |
2552 | HDEBUG(D_acl) debug_printf("ratelimit found key in database\n"); | |
2553 | dbd = &dbdb->dbd; | |
2554 | ||
2555 | /* Forget the old Bloom filter if it is too old, so that we count each | |
2556 | repeating event once per period. We don't simply clear and re-use the old | |
2557 | filter because we want its size to change if the limit changes. Note that | |
2558 | we keep the dbd pointer for copying the rate into the new data block. */ | |
2559 | ||
2560 | if(unique != NULL && tv.tv_sec > dbdb->bloom_epoch + period) | |
2561 | { | |
2562 | HDEBUG(D_acl) debug_printf("ratelimit discarding old Bloom filter\n"); | |
2563 | dbdb = NULL; | |
2564 | } | |
2565 | ||
2566 | /* Sanity check. */ | |
2567 | ||
2568 | if(unique != NULL && dbdb_size < sizeof(*dbdb)) | |
2569 | { | |
2570 | HDEBUG(D_acl) debug_printf("ratelimit discarding undersize Bloom filter\n"); | |
2571 | dbdb = NULL; | |
2572 | } | |
2573 | } | |
2574 | ||
2575 | /* Allocate a new data block if the database lookup failed | |
2576 | or the Bloom filter passed its age limit. */ | |
2577 | ||
2578 | if (dbdb == NULL) | |
2579 | { | |
2580 | if (unique == NULL) | |
2581 | { | |
2582 | /* No Bloom filter. This basic ratelimit block is initialized below. */ | |
2583 | HDEBUG(D_acl) debug_printf("ratelimit creating new rate data block\n"); | |
2584 | dbdb_size = sizeof(*dbd); | |
2585 | dbdb = store_get(dbdb_size); | |
2586 | } | |
2587 | else | |
2588 | { | |
2589 | int extra; | |
2590 | HDEBUG(D_acl) debug_printf("ratelimit creating new Bloom filter\n"); | |
2591 | ||
2592 | /* See the long comment below for an explanation of the magic number 2. | |
2593 | The filter has a minimum size in case the rate limit is very small; | |
2594 | this is determined by the definition of dbdata_ratelimit_unique. */ | |
2595 | ||
2596 | extra = (int)limit * 2 - sizeof(dbdb->bloom); | |
2597 | if (extra < 0) extra = 0; | |
2598 | dbdb_size = sizeof(*dbdb) + extra; | |
2599 | dbdb = store_get(dbdb_size); | |
2600 | dbdb->bloom_epoch = tv.tv_sec; | |
2601 | dbdb->bloom_size = sizeof(dbdb->bloom) + extra; | |
2602 | memset(dbdb->bloom, 0, dbdb->bloom_size); | |
2603 | ||
2604 | /* Preserve any basic ratelimit data (which is our longer-term memory) | |
2605 | by copying it from the discarded block. */ | |
2606 | ||
2607 | if (dbd != NULL) | |
2608 | { | |
2609 | dbdb->dbd = *dbd; | |
2610 | dbd = &dbdb->dbd; | |
2611 | } | |
2612 | } | |
2613 | } | |
2614 | ||
2615 | /* If we are counting unique events, find out if this event is new or not. | |
2616 | If the client repeats the event during the current period then it should be | |
2617 | counted. We skip this code in readonly mode for efficiency, because any | |
2618 | changes to the filter will be discarded and because count is already set to | |
2619 | zero. */ | |
2620 | ||
2621 | if (unique != NULL && !readonly) | |
2622 | { | |
2623 | /* We identify unique events using a Bloom filter. (You can find my | |
2624 | notes on Bloom filters at http://fanf.livejournal.com/81696.html) | |
2625 | With the per_addr option, an "event" is a recipient address, though the | |
2626 | user can use the unique option to define their own events. We only count | |
2627 | an event if we have not seen it before. | |
2628 | ||
2629 | We size the filter according to the rate limit, which (in leaky mode) | |
2630 | is the limit on the population of the filter. We allow 16 bits of space | |
2631 | per entry (see the construction code above) and we set (up to) 8 of them | |
2632 | when inserting an element (see the loop below). The probability of a false | |
2633 | positive (an event we have not seen before but which we fail to count) is | |
2634 | ||
2635 | size = limit * 16 | |
2636 | numhash = 8 | |
2637 | allzero = exp(-numhash * pop / size) | |
2638 | = exp(-0.5 * pop / limit) | |
2639 | fpr = pow(1 - allzero, numhash) | |
2640 | ||
2641 | For senders at the limit the fpr is 0.06% or 1 in 1700 | |
2642 | and for senders at half the limit it is 0.0006% or 1 in 170000 | |
2643 | ||
2644 | In strict mode the Bloom filter can fill up beyond the normal limit, in | |
2645 | which case the false positive rate will rise. This means that the | |
2646 | measured rate for very fast senders can bogusly drop off after a while. | |
2647 | ||
2648 | At twice the limit, the fpr is 2.5% or 1 in 40 | |
2649 | At four times the limit, it is 31% or 1 in 3.2 | |
2650 | ||
2651 | It takes ln(pop/limit) periods for an over-limit burst of pop events to | |
2652 | decay below the limit, and if this is more than one then the Bloom filter | |
2653 | will be discarded before the decay gets that far. The false positive rate | |
2654 | at this threshold is 9.3% or 1 in 10.7. */ | |
2655 | ||
2656 | BOOL seen; | |
2657 | unsigned n, hash, hinc; | |
2658 | uschar md5sum[16]; | |
2659 | md5 md5info; | |
2660 | ||
2661 | /* Instead of using eight independent hash values, we combine two values | |
2662 | using the formula h1 + n * h2. This does not harm the Bloom filter's | |
2663 | performance, and means the amount of hash we need is independent of the | |
2664 | number of bits we set in the filter. */ | |
2665 | ||
2666 | md5_start(&md5info); | |
2667 | md5_end(&md5info, unique, Ustrlen(unique), md5sum); | |
2668 | hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24; | |
2669 | hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24; | |
2670 | ||
2671 | /* Scan the bits corresponding to this event. A zero bit means we have | |
2672 | not seen it before. Ensure all bits are set to record this event. */ | |
2673 | ||
2674 | HDEBUG(D_acl) debug_printf("ratelimit checking uniqueness of %s\n", unique); | |
2675 | ||
2676 | seen = TRUE; | |
2677 | for (n = 0; n < 8; n++, hash += hinc) | |
2678 | { | |
2679 | int bit = 1 << (hash % 8); | |
2680 | int byte = (hash / 8) % dbdb->bloom_size; | |
2681 | if ((dbdb->bloom[byte] & bit) == 0) | |
2682 | { | |
2683 | dbdb->bloom[byte] |= bit; | |
2684 | seen = FALSE; | |
2685 | } | |
2686 | } | |
2687 | ||
2688 | /* If this event has occurred before, do not count it. */ | |
2689 | ||
2690 | if (seen) | |
2691 | { | |
2692 | HDEBUG(D_acl) debug_printf("ratelimit event found in Bloom filter\n"); | |
2693 | count = 0.0; | |
2694 | } | |
2695 | else | |
2696 | HDEBUG(D_acl) debug_printf("ratelimit event added to Bloom filter\n"); | |
2697 | } | |
2698 | ||
2699 | /* If there was no previous ratelimit data block for this key, initialize | |
2700 | the new one, otherwise update the block from the database. The initial rate | |
2701 | is what would be computed by the code below for an infinite interval. */ | |
2702 | ||
2703 | if (dbd == NULL) | |
2704 | { | |
2705 | HDEBUG(D_acl) debug_printf("ratelimit initializing new key's rate data\n"); | |
2706 | dbd = &dbdb->dbd; | |
2707 | dbd->time_stamp = tv.tv_sec; | |
2708 | dbd->time_usec = tv.tv_usec; | |
2709 | dbd->rate = count; | |
2710 | } | |
2711 | else | |
2712 | { | |
2713 | /* The smoothed rate is computed using an exponentially weighted moving | |
2714 | average adjusted for variable sampling intervals. The standard EWMA for | |
2715 | a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1) | |
2716 | where f() is the measured value and f'() is the smoothed value. | |
2717 | ||
2718 | Old data decays out of the smoothed value exponentially, such that data n | |
2719 | samples old is multiplied by a^n. The exponential decay time constant p | |
2720 | is defined such that data p samples old is multiplied by 1/e, which means | |
2721 | that a = exp(-1/p). We can maintain the same time constant for a variable | |
2722 | sampling interval i by using a = exp(-i/p). | |
2723 | ||
2724 | The rate we are measuring is messages per period, suitable for directly | |
2725 | comparing with the limit. The average rate between now and the previous | |
2726 | message is period / interval, which we feed into the EWMA as the sample. | |
2727 | ||
2728 | It turns out that the number of messages required for the smoothed rate | |
2729 | to reach the limit when they are sent in a burst is equal to the limit. | |
2730 | This can be seen by analysing the value of the smoothed rate after N | |
2731 | messages sent at even intervals. Let k = (1 - a) * p/i | |
2732 | ||
2733 | rate_1 = (1 - a) * p/i + a * rate_0 | |
2734 | = k + a * rate_0 | |
2735 | rate_2 = k + a * rate_1 | |
2736 | = k + a * k + a^2 * rate_0 | |
2737 | rate_3 = k + a * k + a^2 * k + a^3 * rate_0 | |
2738 | rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x) | |
2739 | = rate_0 * a^N + k * (1 - a^N) / (1 - a) | |
2740 | = rate_0 * a^N + p/i * (1 - a^N) | |
2741 | ||
2742 | When N is large, a^N -> 0 so rate_N -> p/i as desired. | |
2743 | ||
2744 | rate_N = p/i + (rate_0 - p/i) * a^N | |
2745 | a^N = (rate_N - p/i) / (rate_0 - p/i) | |
2746 | N * -i/p = log((rate_N - p/i) / (rate_0 - p/i)) | |
2747 | N = p/i * log((rate_0 - p/i) / (rate_N - p/i)) | |
2748 | ||
2749 | Numerical analysis of the above equation, setting the computed rate to | |
2750 | increase from rate_0 = 0 to rate_N = limit, shows that for large sending | |
2751 | rates, p/i, the number of messages N = limit. So limit serves as both the | |
2752 | maximum rate measured in messages per period, and the maximum number of | |
2753 | messages that can be sent in a fast burst. */ | |
2754 | ||
2755 | double this_time = (double)tv.tv_sec | |
2756 | + (double)tv.tv_usec / 1000000.0; | |
2757 | double prev_time = (double)dbd->time_stamp | |
2758 | + (double)dbd->time_usec / 1000000.0; | |
2759 | ||
2760 | /* We must avoid division by zero, and deal gracefully with the clock going | |
2761 | backwards. If we blunder ahead when time is in reverse then the computed | |
2762 | rate will be bogus. To be safe we clamp interval to a very small number. */ | |
2763 | ||
2764 | double interval = this_time - prev_time <= 0.0 ? 1e-9 | |
2765 | : this_time - prev_time; | |
2766 | ||
2767 | double i_over_p = interval / period; | |
2768 | double a = exp(-i_over_p); | |
2769 | ||
2770 | /* Combine the instantaneous rate (period / interval) with the previous rate | |
2771 | using the smoothing factor a. In order to measure sized events, multiply the | |
2772 | instantaneous rate by the count of bytes or recipients etc. */ | |
2773 | ||
2774 | dbd->time_stamp = tv.tv_sec; | |
2775 | dbd->time_usec = tv.tv_usec; | |
2776 | dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate; | |
2777 | ||
2778 | /* When events are very widely spaced the computed rate tends towards zero. | |
2779 | Although this is accurate it turns out not to be useful for our purposes, | |
2780 | especially when the first event after a long silence is the start of a spam | |
2781 | run. A more useful model is that the rate for an isolated event should be the | |
2782 | size of the event per the period size, ignoring the lack of events outside | |
2783 | the current period and regardless of where the event falls in the period. So, | |
2784 | if the interval was so long that the calculated rate is unhelpfully small, we | |
2785 | re-intialize the rate. In the absence of higher-rate bursts, the condition | |
2786 | below is true if the interval is greater than the period. */ | |
2787 | ||
2788 | if (dbd->rate < count) dbd->rate = count; | |
2789 | } | |
2790 | ||
2791 | /* Clients sending at the limit are considered to be over the limit. | |
2792 | This matters for edge cases such as a limit of zero, when the client | |
2793 | should be completely blocked. */ | |
2794 | ||
2795 | rc = (dbd->rate < limit)? FAIL : OK; | |
2796 | ||
2797 | /* Update the state if the rate is low or if we are being strict. If we | |
2798 | are in leaky mode and the sender's rate is too high, we do not update | |
2799 | the recorded rate in order to avoid an over-aggressive sender's retry | |
2800 | rate preventing them from getting any email through. If readonly is set, | |
2801 | neither leaky nor strict are set, so we do not do any updates. */ | |
2802 | ||
2803 | if ((rc == FAIL && leaky) || strict) | |
2804 | { | |
2805 | dbfn_write(dbm, key, dbdb, dbdb_size); | |
2806 | HDEBUG(D_acl) debug_printf("ratelimit db updated\n"); | |
2807 | } | |
2808 | else | |
2809 | { | |
2810 | HDEBUG(D_acl) debug_printf("ratelimit db not updated: %s\n", | |
2811 | readonly? "readonly mode" : "over the limit, but leaky"); | |
2812 | } | |
2813 | ||
2814 | dbfn_close(dbm); | |
2815 | ||
2816 | /* Store the result in the tree for future reference. */ | |
2817 | ||
2818 | t = store_get(sizeof(tree_node) + Ustrlen(key)); | |
2819 | t->data.ptr = dbd; | |
2820 | Ustrcpy(t->name, key); | |
2821 | (void)tree_insertnode(anchor, t); | |
2822 | ||
2823 | /* We create the formatted version of the sender's rate very late in | |
2824 | order to ensure that it is done using the correct storage pool. */ | |
2825 | ||
2826 | store_pool = old_pool; | |
2827 | sender_rate = string_sprintf("%.1f", dbd->rate); | |
2828 | ||
2829 | HDEBUG(D_acl) | |
2830 | debug_printf("ratelimit computed rate %s\n", sender_rate); | |
2831 | ||
2832 | return rc; | |
2833 | } | |
2834 | ||
2835 | ||
2836 | ||
2837 | /************************************************* | |
2838 | * The udpsend ACL modifier * | |
2839 | *************************************************/ | |
2840 | ||
2841 | /* Called by acl_check_condition() below. | |
2842 | ||
2843 | Arguments: | |
2844 | arg the option string for udpsend= | |
2845 | log_msgptr for error messages | |
2846 | ||
2847 | Returns: OK - Completed. | |
2848 | DEFER - Problem with DNS lookup. | |
2849 | ERROR - Syntax error in options. | |
2850 | */ | |
2851 | ||
2852 | static int | |
2853 | acl_udpsend(uschar *arg, uschar **log_msgptr) | |
2854 | { | |
2855 | int sep = 0; | |
2856 | uschar *hostname; | |
2857 | uschar *portstr; | |
2858 | uschar *portend; | |
2859 | host_item *h; | |
2860 | int portnum; | |
2861 | int len; | |
2862 | int r, s; | |
2863 | uschar * errstr; | |
2864 | ||
2865 | hostname = string_nextinlist(&arg, &sep, NULL, 0); | |
2866 | portstr = string_nextinlist(&arg, &sep, NULL, 0); | |
2867 | ||
2868 | if (hostname == NULL) | |
2869 | { | |
2870 | *log_msgptr = US"missing destination host in \"udpsend\" modifier"; | |
2871 | return ERROR; | |
2872 | } | |
2873 | if (portstr == NULL) | |
2874 | { | |
2875 | *log_msgptr = US"missing destination port in \"udpsend\" modifier"; | |
2876 | return ERROR; | |
2877 | } | |
2878 | if (arg == NULL) | |
2879 | { | |
2880 | *log_msgptr = US"missing datagram payload in \"udpsend\" modifier"; | |
2881 | return ERROR; | |
2882 | } | |
2883 | portnum = Ustrtol(portstr, &portend, 10); | |
2884 | if (*portend != '\0') | |
2885 | { | |
2886 | *log_msgptr = US"bad destination port in \"udpsend\" modifier"; | |
2887 | return ERROR; | |
2888 | } | |
2889 | ||
2890 | /* Make a single-item host list. */ | |
2891 | h = store_get(sizeof(host_item)); | |
2892 | memset(h, 0, sizeof(host_item)); | |
2893 | h->name = hostname; | |
2894 | h->port = portnum; | |
2895 | h->mx = MX_NONE; | |
2896 | ||
2897 | if (string_is_ip_address(hostname, NULL)) | |
2898 | h->address = hostname, r = HOST_FOUND; | |
2899 | else | |
2900 | r = host_find_byname(h, NULL, 0, NULL, FALSE); | |
2901 | if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN) | |
2902 | { | |
2903 | *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier"; | |
2904 | return DEFER; | |
2905 | } | |
2906 | ||
2907 | HDEBUG(D_acl) | |
2908 | debug_printf("udpsend [%s]:%d %s\n", h->address, portnum, arg); | |
2909 | ||
2910 | r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum, | |
2911 | 1, NULL, &errstr); | |
2912 | if (r < 0) goto defer; | |
2913 | len = Ustrlen(arg); | |
2914 | r = send(s, arg, len, 0); | |
2915 | if (r < 0) | |
2916 | { | |
2917 | errstr = US strerror(errno); | |
2918 | close(s); | |
2919 | goto defer; | |
2920 | } | |
2921 | close(s); | |
2922 | if (r < len) | |
2923 | { | |
2924 | *log_msgptr = | |
2925 | string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r); | |
2926 | return DEFER; | |
2927 | } | |
2928 | ||
2929 | HDEBUG(D_acl) | |
2930 | debug_printf("udpsend %d bytes\n", r); | |
2931 | ||
2932 | return OK; | |
2933 | ||
2934 | defer: | |
2935 | *log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr); | |
2936 | return DEFER; | |
2937 | } | |
2938 | ||
2939 | ||
2940 | ||
2941 | /************************************************* | |
2942 | * Handle conditions/modifiers on an ACL item * | |
2943 | *************************************************/ | |
2944 | ||
2945 | /* Called from acl_check() below. | |
2946 | ||
2947 | Arguments: | |
2948 | verb ACL verb | |
2949 | cb ACL condition block - if NULL, result is OK | |
2950 | where where called from | |
2951 | addr the address being checked for RCPT, or NULL | |
2952 | level the nesting level | |
2953 | epp pointer to pass back TRUE if "endpass" encountered | |
2954 | (applies only to "accept" and "discard") | |
2955 | user_msgptr user message pointer | |
2956 | log_msgptr log message pointer | |
2957 | basic_errno pointer to where to put verify error | |
2958 | ||
2959 | Returns: OK - all conditions are met | |
2960 | DISCARD - an "acl" condition returned DISCARD - only allowed | |
2961 | for "accept" or "discard" verbs | |
2962 | FAIL - at least one condition fails | |
2963 | FAIL_DROP - an "acl" condition returned FAIL_DROP | |
2964 | DEFER - can't tell at the moment (typically, lookup defer, | |
2965 | but can be temporary callout problem) | |
2966 | ERROR - ERROR from nested ACL or expansion failure or other | |
2967 | error | |
2968 | */ | |
2969 | ||
2970 | static int | |
2971 | acl_check_condition(int verb, acl_condition_block *cb, int where, | |
2972 | address_item *addr, int level, BOOL *epp, uschar **user_msgptr, | |
2973 | uschar **log_msgptr, int *basic_errno) | |
2974 | { | |
2975 | uschar *user_message = NULL; | |
2976 | uschar *log_message = NULL; | |
2977 | uschar *debug_tag = NULL; | |
2978 | uschar *debug_opts = NULL; | |
2979 | uschar *p = NULL; | |
2980 | int rc = OK; | |
2981 | #ifdef WITH_CONTENT_SCAN | |
2982 | int sep = '/'; | |
2983 | #endif | |
2984 | ||
2985 | for (; cb != NULL; cb = cb->next) | |
2986 | { | |
2987 | uschar *arg; | |
2988 | int control_type; | |
2989 | ||
2990 | /* The message and log_message items set up messages to be used in | |
2991 | case of rejection. They are expanded later. */ | |
2992 | ||
2993 | if (cb->type == ACLC_MESSAGE) | |
2994 | { | |
2995 | HDEBUG(D_acl) debug_printf(" message: %s\n", cb->arg); | |
2996 | user_message = cb->arg; | |
2997 | continue; | |
2998 | } | |
2999 | ||
3000 | if (cb->type == ACLC_LOG_MESSAGE) | |
3001 | { | |
3002 | HDEBUG(D_acl) debug_printf("l_message: %s\n", cb->arg); | |
3003 | log_message = cb->arg; | |
3004 | continue; | |
3005 | } | |
3006 | ||
3007 | /* The endpass "condition" just sets a flag to show it occurred. This is | |
3008 | checked at compile time to be on an "accept" or "discard" item. */ | |
3009 | ||
3010 | if (cb->type == ACLC_ENDPASS) | |
3011 | { | |
3012 | *epp = TRUE; | |
3013 | continue; | |
3014 | } | |
3015 | ||
3016 | /* For other conditions and modifiers, the argument is expanded now for some | |
3017 | of them, but not for all, because expansion happens down in some lower level | |
3018 | checking functions in some cases. */ | |
3019 | ||
3020 | if (cond_expand_at_top[cb->type]) | |
3021 | { | |
3022 | arg = expand_string(cb->arg); | |
3023 | if (arg == NULL) | |
3024 | { | |
3025 | if (expand_string_forcedfail) continue; | |
3026 | *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", | |
3027 | cb->arg, expand_string_message); | |
3028 | return search_find_defer? DEFER : ERROR; | |
3029 | } | |
3030 | } | |
3031 | else arg = cb->arg; | |
3032 | ||
3033 | /* Show condition, and expanded condition if it's different */ | |
3034 | ||
3035 | HDEBUG(D_acl) | |
3036 | { | |
3037 | int lhswidth = 0; | |
3038 | debug_printf("check %s%s %n", | |
3039 | (!cond_modifiers[cb->type] && cb->u.negated)? "!":"", | |
3040 | conditions[cb->type], &lhswidth); | |
3041 | ||
3042 | if (cb->type == ACLC_SET) | |
3043 | { | |
3044 | debug_printf("acl_%s ", cb->u.varname); | |
3045 | lhswidth += 5 + Ustrlen(cb->u.varname); | |
3046 | } | |
3047 | ||
3048 | debug_printf("= %s\n", cb->arg); | |
3049 | ||
3050 | if (arg != cb->arg) | |
3051 | debug_printf("%.*s= %s\n", lhswidth, | |
3052 | US" ", CS arg); | |
3053 | } | |
3054 | ||
3055 | /* Check that this condition makes sense at this time */ | |
3056 | ||
3057 | if ((cond_forbids[cb->type] & (1 << where)) != 0) | |
3058 | { | |
3059 | *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL", | |
3060 | cond_modifiers[cb->type]? "use" : "test", | |
3061 | conditions[cb->type], acl_wherenames[where]); | |
3062 | return ERROR; | |
3063 | } | |
3064 | ||
3065 | /* Run the appropriate test for each condition, or take the appropriate | |
3066 | action for the remaining modifiers. */ | |
3067 | ||
3068 | switch(cb->type) | |
3069 | { | |
3070 | case ACLC_ADD_HEADER: | |
3071 | setup_header(arg); | |
3072 | break; | |
3073 | ||
3074 | /* A nested ACL that returns "discard" makes sense only for an "accept" or | |
3075 | "discard" verb. */ | |
3076 | ||
3077 | case ACLC_ACL: | |
3078 | rc = acl_check_wargs(where, addr, arg, level+1, user_msgptr, log_msgptr); | |
3079 | if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD) | |
3080 | { | |
3081 | *log_msgptr = string_sprintf("nested ACL returned \"discard\" for " | |
3082 | "\"%s\" command (only allowed with \"accept\" or \"discard\")", | |
3083 | verbs[verb]); | |
3084 | return ERROR; | |
3085 | } | |
3086 | break; | |
3087 | ||
3088 | case ACLC_AUTHENTICATED: | |
3089 | rc = (sender_host_authenticated == NULL)? FAIL : | |
3090 | match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING, | |
3091 | TRUE, NULL); | |
3092 | break; | |
3093 | ||
3094 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
3095 | case ACLC_BMI_OPTIN: | |
3096 | { | |
3097 | int old_pool = store_pool; | |
3098 | store_pool = POOL_PERM; | |
3099 | bmi_current_optin = string_copy(arg); | |
3100 | store_pool = old_pool; | |
3101 | } | |
3102 | break; | |
3103 | #endif | |
3104 | ||
3105 | case ACLC_CONDITION: | |
3106 | /* The true/false parsing here should be kept in sync with that used in | |
3107 | expand.c when dealing with ECOND_BOOL so that we don't have too many | |
3108 | different definitions of what can be a boolean. */ | |
3109 | if (*arg == '-' | |
3110 | ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */ | |
3111 | : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */ | |
3112 | rc = (Uatoi(arg) == 0)? FAIL : OK; | |
3113 | else | |
3114 | rc = (strcmpic(arg, US"no") == 0 || | |
3115 | strcmpic(arg, US"false") == 0)? FAIL : | |
3116 | (strcmpic(arg, US"yes") == 0 || | |
3117 | strcmpic(arg, US"true") == 0)? OK : DEFER; | |
3118 | if (rc == DEFER) | |
3119 | *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg); | |
3120 | break; | |
3121 | ||
3122 | case ACLC_CONTINUE: /* Always succeeds */ | |
3123 | break; | |
3124 | ||
3125 | case ACLC_CONTROL: | |
3126 | control_type = decode_control(arg, &p, where, log_msgptr); | |
3127 | ||
3128 | /* Check if this control makes sense at this time */ | |
3129 | ||
3130 | if ((control_forbids[control_type] & (1 << where)) != 0) | |
3131 | { | |
3132 | *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL", | |
3133 | controls[control_type], acl_wherenames[where]); | |
3134 | return ERROR; | |
3135 | } | |
3136 | ||
3137 | switch(control_type) | |
3138 | { | |
3139 | case CONTROL_AUTH_UNADVERTISED: | |
3140 | allow_auth_unadvertised = TRUE; | |
3141 | break; | |
3142 | ||
3143 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
3144 | case CONTROL_BMI_RUN: | |
3145 | bmi_run = 1; | |
3146 | break; | |
3147 | #endif | |
3148 | ||
3149 | #ifndef DISABLE_DKIM | |
3150 | case CONTROL_DKIM_VERIFY: | |
3151 | dkim_disable_verify = TRUE; | |
3152 | #ifdef EXPERIMENTAL_DMARC | |
3153 | /* Since DKIM was blocked, skip DMARC too */ | |
3154 | dmarc_disable_verify = TRUE; | |
3155 | dmarc_enable_forensic = FALSE; | |
3156 | #endif | |
3157 | break; | |
3158 | #endif | |
3159 | ||
3160 | #ifdef EXPERIMENTAL_DMARC | |
3161 | case CONTROL_DMARC_VERIFY: | |
3162 | dmarc_disable_verify = TRUE; | |
3163 | break; | |
3164 | ||
3165 | case CONTROL_DMARC_FORENSIC: | |
3166 | dmarc_enable_forensic = TRUE; | |
3167 | break; | |
3168 | #endif | |
3169 | ||
3170 | case CONTROL_DSCP: | |
3171 | if (*p == '/') | |
3172 | { | |
3173 | int fd, af, level, optname, value; | |
3174 | /* If we are acting on stdin, the setsockopt may fail if stdin is not | |
3175 | a socket; we can accept that, we'll just debug-log failures anyway. */ | |
3176 | fd = fileno(smtp_in); | |
3177 | af = ip_get_address_family(fd); | |
3178 | if (af < 0) | |
3179 | { | |
3180 | HDEBUG(D_acl) | |
3181 | debug_printf("smtp input is probably not a socket [%s], not setting DSCP\n", | |
3182 | strerror(errno)); | |
3183 | break; | |
3184 | } | |
3185 | if (dscp_lookup(p+1, af, &level, &optname, &value)) | |
3186 | { | |
3187 | if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0) | |
3188 | { | |
3189 | HDEBUG(D_acl) debug_printf("failed to set input DSCP[%s]: %s\n", | |
3190 | p+1, strerror(errno)); | |
3191 | } | |
3192 | else | |
3193 | { | |
3194 | HDEBUG(D_acl) debug_printf("set input DSCP to \"%s\"\n", p+1); | |
3195 | } | |
3196 | } | |
3197 | else | |
3198 | { | |
3199 | *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg); | |
3200 | return ERROR; | |
3201 | } | |
3202 | } | |
3203 | else | |
3204 | { | |
3205 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); | |
3206 | return ERROR; | |
3207 | } | |
3208 | break; | |
3209 | ||
3210 | case CONTROL_ERROR: | |
3211 | return ERROR; | |
3212 | ||
3213 | case CONTROL_CASEFUL_LOCAL_PART: | |
3214 | deliver_localpart = addr->cc_local_part; | |
3215 | break; | |
3216 | ||
3217 | case CONTROL_CASELOWER_LOCAL_PART: | |
3218 | deliver_localpart = addr->lc_local_part; | |
3219 | break; | |
3220 | ||
3221 | case CONTROL_ENFORCE_SYNC: | |
3222 | smtp_enforce_sync = TRUE; | |
3223 | break; | |
3224 | ||
3225 | case CONTROL_NO_ENFORCE_SYNC: | |
3226 | smtp_enforce_sync = FALSE; | |
3227 | break; | |
3228 | ||
3229 | #ifdef WITH_CONTENT_SCAN | |
3230 | case CONTROL_NO_MBOX_UNSPOOL: | |
3231 | no_mbox_unspool = TRUE; | |
3232 | break; | |
3233 | #endif | |
3234 | ||
3235 | case CONTROL_NO_MULTILINE: | |
3236 | no_multiline_responses = TRUE; | |
3237 | break; | |
3238 | ||
3239 | case CONTROL_NO_PIPELINING: | |
3240 | pipelining_enable = FALSE; | |
3241 | break; | |
3242 | ||
3243 | case CONTROL_NO_DELAY_FLUSH: | |
3244 | disable_delay_flush = TRUE; | |
3245 | break; | |
3246 | ||
3247 | case CONTROL_NO_CALLOUT_FLUSH: | |
3248 | disable_callout_flush = TRUE; | |
3249 | break; | |
3250 | ||
3251 | case CONTROL_FAKEREJECT: | |
3252 | cancel_cutthrough_connection("fakereject"); | |
3253 | case CONTROL_FAKEDEFER: | |
3254 | fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL; | |
3255 | if (*p == '/') | |
3256 | { | |
3257 | uschar *pp = p + 1; | |
3258 | while (*pp != 0) pp++; | |
3259 | fake_response_text = expand_string(string_copyn(p+1, pp-p-1)); | |
3260 | p = pp; | |
3261 | } | |
3262 | else | |
3263 | { | |
3264 | /* Explicitly reset to default string */ | |
3265 | fake_response_text = US"Your message has been rejected but is being kept for evaluation.\nIf it was a legitimate message, it may still be delivered to the target recipient(s)."; | |
3266 | } | |
3267 | break; | |
3268 | ||
3269 | case CONTROL_FREEZE: | |
3270 | deliver_freeze = TRUE; | |
3271 | deliver_frozen_at = time(NULL); | |
3272 | freeze_tell = freeze_tell_config; /* Reset to configured value */ | |
3273 | if (Ustrncmp(p, "/no_tell", 8) == 0) | |
3274 | { | |
3275 | p += 8; | |
3276 | freeze_tell = NULL; | |
3277 | } | |
3278 | if (*p != 0) | |
3279 | { | |
3280 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); | |
3281 | return ERROR; | |
3282 | } | |
3283 | cancel_cutthrough_connection("item frozen"); | |
3284 | break; | |
3285 | ||
3286 | case CONTROL_QUEUE_ONLY: | |
3287 | queue_only_policy = TRUE; | |
3288 | cancel_cutthrough_connection("queueing forced"); | |
3289 | break; | |
3290 | ||
3291 | case CONTROL_SUBMISSION: | |
3292 | originator_name = US""; | |
3293 | submission_mode = TRUE; | |
3294 | while (*p == '/') | |
3295 | { | |
3296 | if (Ustrncmp(p, "/sender_retain", 14) == 0) | |
3297 | { | |
3298 | p += 14; | |
3299 | active_local_sender_retain = TRUE; | |
3300 | active_local_from_check = FALSE; | |
3301 | } | |
3302 | else if (Ustrncmp(p, "/domain=", 8) == 0) | |
3303 | { | |
3304 | uschar *pp = p + 8; | |
3305 | while (*pp != 0 && *pp != '/') pp++; | |
3306 | submission_domain = string_copyn(p+8, pp-p-8); | |
3307 | p = pp; | |
3308 | } | |
3309 | /* The name= option must be last, because it swallows the rest of | |
3310 | the string. */ | |
3311 | else if (Ustrncmp(p, "/name=", 6) == 0) | |
3312 | { | |
3313 | uschar *pp = p + 6; | |
3314 | while (*pp != 0) pp++; | |
3315 | submission_name = string_copy(parse_fix_phrase(p+6, pp-p-6, | |
3316 | big_buffer, big_buffer_size)); | |
3317 | p = pp; | |
3318 | } | |
3319 | else break; | |
3320 | } | |
3321 | if (*p != 0) | |
3322 | { | |
3323 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); | |
3324 | return ERROR; | |
3325 | } | |
3326 | break; | |
3327 | ||
3328 | case CONTROL_DEBUG: | |
3329 | while (*p == '/') | |
3330 | { | |
3331 | if (Ustrncmp(p, "/tag=", 5) == 0) | |
3332 | { | |
3333 | uschar *pp = p + 5; | |
3334 | while (*pp != '\0' && *pp != '/') pp++; | |
3335 | debug_tag = string_copyn(p+5, pp-p-5); | |
3336 | p = pp; | |
3337 | } | |
3338 | else if (Ustrncmp(p, "/opts=", 6) == 0) | |
3339 | { | |
3340 | uschar *pp = p + 6; | |
3341 | while (*pp != '\0' && *pp != '/') pp++; | |
3342 | debug_opts = string_copyn(p+6, pp-p-6); | |
3343 | p = pp; | |
3344 | } | |
3345 | } | |
3346 | debug_logging_activate(debug_tag, debug_opts); | |
3347 | break; | |
3348 | ||
3349 | case CONTROL_SUPPRESS_LOCAL_FIXUPS: | |
3350 | suppress_local_fixups = TRUE; | |
3351 | break; | |
3352 | ||
3353 | case CONTROL_CUTTHROUGH_DELIVERY: | |
3354 | if (deliver_freeze) | |
3355 | *log_msgptr = US"frozen"; | |
3356 | else if (queue_only_policy) | |
3357 | *log_msgptr = US"queue-only"; | |
3358 | else if (fake_response == FAIL) | |
3359 | *log_msgptr = US"fakereject"; | |
3360 | else | |
3361 | { | |
3362 | cutthrough_delivery = TRUE; | |
3363 | break; | |
3364 | } | |
3365 | *log_msgptr = string_sprintf("\"control=%s\" on %s item", | |
3366 | arg, *log_msgptr); | |
3367 | return ERROR; | |
3368 | } | |
3369 | break; | |
3370 | ||
3371 | #ifdef EXPERIMENTAL_DCC | |
3372 | case ACLC_DCC: | |
3373 | { | |
3374 | /* Seperate the regular expression and any optional parameters. */ | |
3375 | uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size); | |
3376 | /* Run the dcc backend. */ | |
3377 | rc = dcc_process(&ss); | |
3378 | /* Modify return code based upon the existance of options. */ | |
3379 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) | |
3380 | != NULL) { | |
3381 | if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER) | |
3382 | { | |
3383 | /* FAIL so that the message is passed to the next ACL */ | |
3384 | rc = FAIL; | |
3385 | } | |
3386 | } | |
3387 | } | |
3388 | break; | |
3389 | #endif | |
3390 | ||
3391 | #ifdef WITH_CONTENT_SCAN | |
3392 | case ACLC_DECODE: | |
3393 | rc = mime_decode(&arg); | |
3394 | break; | |
3395 | #endif | |
3396 | ||
3397 | case ACLC_DELAY: | |
3398 | { | |
3399 | int delay = readconf_readtime(arg, 0, FALSE); | |
3400 | if (delay < 0) | |
3401 | { | |
3402 | *log_msgptr = string_sprintf("syntax error in argument for \"delay\" " | |
3403 | "modifier: \"%s\" is not a time value", arg); | |
3404 | return ERROR; | |
3405 | } | |
3406 | else | |
3407 | { | |
3408 | HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n", | |
3409 | delay); | |
3410 | if (host_checking) | |
3411 | { | |
3412 | HDEBUG(D_acl) | |
3413 | debug_printf("delay skipped in -bh checking mode\n"); | |
3414 | } | |
3415 | ||
3416 | /* It appears to be impossible to detect that a TCP/IP connection has | |
3417 | gone away without reading from it. This means that we cannot shorten | |
3418 | the delay below if the client goes away, because we cannot discover | |
3419 | that the client has closed its end of the connection. (The connection | |
3420 | is actually in a half-closed state, waiting for the server to close its | |
3421 | end.) It would be nice to be able to detect this state, so that the | |
3422 | Exim process is not held up unnecessarily. However, it seems that we | |
3423 | can't. The poll() function does not do the right thing, and in any case | |
3424 | it is not always available. | |
3425 | ||
3426 | NOTE 1: If ever this state of affairs changes, remember that we may be | |
3427 | dealing with stdin/stdout here, in addition to TCP/IP connections. | |
3428 | Also, delays may be specified for non-SMTP input, where smtp_out and | |
3429 | smtp_in will be NULL. Whatever is done must work in all cases. | |
3430 | ||
3431 | NOTE 2: The added feature of flushing the output before a delay must | |
3432 | apply only to SMTP input. Hence the test for smtp_out being non-NULL. | |
3433 | */ | |
3434 | ||
3435 | else | |
3436 | { | |
3437 | if (smtp_out != NULL && !disable_delay_flush) mac_smtp_fflush(); | |
3438 | while (delay > 0) delay = sleep(delay); | |
3439 | } | |
3440 | } | |
3441 | } | |
3442 | break; | |
3443 | ||
3444 | #ifdef WITH_OLD_DEMIME | |
3445 | case ACLC_DEMIME: | |
3446 | rc = demime(&arg); | |
3447 | break; | |
3448 | #endif | |
3449 | ||
3450 | #ifndef DISABLE_DKIM | |
3451 | case ACLC_DKIM_SIGNER: | |
3452 | if (dkim_cur_signer != NULL) | |
3453 | rc = match_isinlist(dkim_cur_signer, | |
3454 | &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL); | |
3455 | else | |
3456 | rc = FAIL; | |
3457 | break; | |
3458 | ||
3459 | case ACLC_DKIM_STATUS: | |
3460 | rc = match_isinlist(dkim_exim_expand_query(DKIM_VERIFY_STATUS), | |
3461 | &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL); | |
3462 | break; | |
3463 | #endif | |
3464 | ||
3465 | #ifdef EXPERIMENTAL_DMARC | |
3466 | case ACLC_DMARC_STATUS: | |
3467 | if (!dmarc_has_been_checked) | |
3468 | dmarc_process(); | |
3469 | dmarc_has_been_checked = TRUE; | |
3470 | /* used long way of dmarc_exim_expand_query() in case we need more | |
3471 | * view into the process in the future. */ | |
3472 | rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS), | |
3473 | &arg,0,NULL,NULL,MCL_STRING,TRUE,NULL); | |
3474 | break; | |
3475 | #endif | |
3476 | ||
3477 | case ACLC_DNSLISTS: | |
3478 | rc = verify_check_dnsbl(&arg); | |
3479 | break; | |
3480 | ||
3481 | case ACLC_DOMAINS: | |
3482 | rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor, | |
3483 | addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data); | |
3484 | break; | |
3485 | ||
3486 | /* The value in tls_cipher is the full cipher name, for example, | |
3487 | TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the | |
3488 | cipher names such as DES-CBC3-SHA. But program defensively. We don't know | |
3489 | what may in practice come out of the SSL library - which at the time of | |
3490 | writing is poorly documented. */ | |
3491 | ||
3492 | case ACLC_ENCRYPTED: | |
3493 | if (tls_in.cipher == NULL) rc = FAIL; else | |
3494 | { | |
3495 | uschar *endcipher = NULL; | |
3496 | uschar *cipher = Ustrchr(tls_in.cipher, ':'); | |
3497 | if (cipher == NULL) cipher = tls_in.cipher; else | |
3498 | { | |
3499 | endcipher = Ustrchr(++cipher, ':'); | |
3500 | if (endcipher != NULL) *endcipher = 0; | |
3501 | } | |
3502 | rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL); | |
3503 | if (endcipher != NULL) *endcipher = ':'; | |
3504 | } | |
3505 | break; | |
3506 | ||
3507 | /* Use verify_check_this_host() instead of verify_check_host() so that | |
3508 | we can pass over &host_data to catch any looked up data. Once it has been | |
3509 | set, it retains its value so that it's still there if another ACL verb | |
3510 | comes through here and uses the cache. However, we must put it into | |
3511 | permanent store in case it is also expected to be used in a subsequent | |
3512 | message in the same SMTP connection. */ | |
3513 | ||
3514 | case ACLC_HOSTS: | |
3515 | rc = verify_check_this_host(&arg, sender_host_cache, NULL, | |
3516 | (sender_host_address == NULL)? US"" : sender_host_address, &host_data); | |
3517 | if (host_data != NULL) host_data = string_copy_malloc(host_data); | |
3518 | break; | |
3519 | ||
3520 | case ACLC_LOCAL_PARTS: | |
3521 | rc = match_isinlist(addr->cc_local_part, &arg, 0, | |
3522 | &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE, | |
3523 | &deliver_localpart_data); | |
3524 | break; | |
3525 | ||
3526 | case ACLC_LOG_REJECT_TARGET: | |
3527 | { | |
3528 | int logbits = 0; | |
3529 | int sep = 0; | |
3530 | uschar *s = arg; | |
3531 | uschar *ss; | |
3532 | while ((ss = string_nextinlist(&s, &sep, big_buffer, big_buffer_size)) | |
3533 | != NULL) | |
3534 | { | |
3535 | if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN; | |
3536 | else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC; | |
3537 | else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT; | |
3538 | else | |
3539 | { | |
3540 | logbits |= LOG_MAIN|LOG_REJECT; | |
3541 | log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in " | |
3542 | "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]); | |
3543 | } | |
3544 | } | |
3545 | log_reject_target = logbits; | |
3546 | } | |
3547 | break; | |
3548 | ||
3549 | case ACLC_LOGWRITE: | |
3550 | { | |
3551 | int logbits = 0; | |
3552 | uschar *s = arg; | |
3553 | if (*s == ':') | |
3554 | { | |
3555 | s++; | |
3556 | while (*s != ':') | |
3557 | { | |
3558 | if (Ustrncmp(s, "main", 4) == 0) | |
3559 | { logbits |= LOG_MAIN; s += 4; } | |
3560 | else if (Ustrncmp(s, "panic", 5) == 0) | |
3561 | { logbits |= LOG_PANIC; s += 5; } | |
3562 | else if (Ustrncmp(s, "reject", 6) == 0) | |
3563 | { logbits |= LOG_REJECT; s += 6; } | |
3564 | else | |
3565 | { | |
3566 | logbits = LOG_MAIN|LOG_PANIC; | |
3567 | s = string_sprintf(":unknown log name in \"%s\" in " | |
3568 | "\"logwrite\" in %s ACL", arg, acl_wherenames[where]); | |
3569 | } | |
3570 | if (*s == ',') s++; | |
3571 | } | |
3572 | s++; | |
3573 | } | |
3574 | while (isspace(*s)) s++; | |
3575 | ||
3576 | ||
3577 | if (logbits == 0) logbits = LOG_MAIN; | |
3578 | log_write(0, logbits, "%s", string_printing(s)); | |
3579 | } | |
3580 | break; | |
3581 | ||
3582 | #ifdef WITH_CONTENT_SCAN | |
3583 | case ACLC_MALWARE: | |
3584 | { | |
3585 | /* Separate the regular expression and any optional parameters. */ | |
3586 | uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size); | |
3587 | /* Run the malware backend. */ | |
3588 | rc = malware(&ss); | |
3589 | /* Modify return code based upon the existance of options. */ | |
3590 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) | |
3591 | != NULL) { | |
3592 | if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER) | |
3593 | { | |
3594 | /* FAIL so that the message is passed to the next ACL */ | |
3595 | rc = FAIL; | |
3596 | } | |
3597 | } | |
3598 | } | |
3599 | break; | |
3600 | ||
3601 | case ACLC_MIME_REGEX: | |
3602 | rc = mime_regex(&arg); | |
3603 | break; | |
3604 | #endif | |
3605 | ||
3606 | case ACLC_RATELIMIT: | |
3607 | rc = acl_ratelimit(arg, where, log_msgptr); | |
3608 | break; | |
3609 | ||
3610 | case ACLC_RECIPIENTS: | |
3611 | rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0, | |
3612 | &recipient_data); | |
3613 | break; | |
3614 | ||
3615 | #ifdef WITH_CONTENT_SCAN | |
3616 | case ACLC_REGEX: | |
3617 | rc = regex(&arg); | |
3618 | break; | |
3619 | #endif | |
3620 | ||
3621 | case ACLC_REMOVE_HEADER: | |
3622 | setup_remove_header(arg); | |
3623 | break; | |
3624 | ||
3625 | case ACLC_SENDER_DOMAINS: | |
3626 | { | |
3627 | uschar *sdomain; | |
3628 | sdomain = Ustrrchr(sender_address, '@'); | |
3629 | sdomain = (sdomain == NULL)? US"" : sdomain + 1; | |
3630 | rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor, | |
3631 | sender_domain_cache, MCL_DOMAIN, TRUE, NULL); | |
3632 | } | |
3633 | break; | |
3634 | ||
3635 | case ACLC_SENDERS: | |
3636 | rc = match_address_list(sender_address, TRUE, TRUE, &arg, | |
3637 | sender_address_cache, -1, 0, &sender_data); | |
3638 | break; | |
3639 | ||
3640 | /* Connection variables must persist forever */ | |
3641 | ||
3642 | case ACLC_SET: | |
3643 | { | |
3644 | int old_pool = store_pool; | |
3645 | if (cb->u.varname[0] == 'c') store_pool = POOL_PERM; | |
3646 | acl_var_create(cb->u.varname)->data.ptr = string_copy(arg); | |
3647 | store_pool = old_pool; | |
3648 | } | |
3649 | break; | |
3650 | ||
3651 | #ifdef WITH_CONTENT_SCAN | |
3652 | case ACLC_SPAM: | |
3653 | { | |
3654 | /* Seperate the regular expression and any optional parameters. */ | |
3655 | uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size); | |
3656 | /* Run the spam backend. */ | |
3657 | rc = spam(&ss); | |
3658 | /* Modify return code based upon the existance of options. */ | |
3659 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) | |
3660 | != NULL) { | |
3661 | if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER) | |
3662 | { | |
3663 | /* FAIL so that the message is passed to the next ACL */ | |
3664 | rc = FAIL; | |
3665 | } | |
3666 | } | |
3667 | } | |
3668 | break; | |
3669 | #endif | |
3670 | ||
3671 | #ifdef EXPERIMENTAL_SPF | |
3672 | case ACLC_SPF: | |
3673 | rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL); | |
3674 | break; | |
3675 | case ACLC_SPF_GUESS: | |
3676 | rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS); | |
3677 | break; | |
3678 | #endif | |
3679 | ||
3680 | case ACLC_UDPSEND: | |
3681 | rc = acl_udpsend(arg, log_msgptr); | |
3682 | break; | |
3683 | ||
3684 | /* If the verb is WARN, discard any user message from verification, because | |
3685 | such messages are SMTP responses, not header additions. The latter come | |
3686 | only from explicit "message" modifiers. However, put the user message into | |
3687 | $acl_verify_message so it can be used in subsequent conditions or modifiers | |
3688 | (until something changes it). */ | |
3689 | ||
3690 | case ACLC_VERIFY: | |
3691 | rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno); | |
3692 | acl_verify_message = *user_msgptr; | |
3693 | if (verb == ACL_WARN) *user_msgptr = NULL; | |
3694 | break; | |
3695 | ||
3696 | default: | |
3697 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown " | |
3698 | "condition %d", cb->type); | |
3699 | break; | |
3700 | } | |
3701 | ||
3702 | /* If a condition was negated, invert OK/FAIL. */ | |
3703 | ||
3704 | if (!cond_modifiers[cb->type] && cb->u.negated) | |
3705 | { | |
3706 | if (rc == OK) rc = FAIL; | |
3707 | else if (rc == FAIL || rc == FAIL_DROP) rc = OK; | |
3708 | } | |
3709 | ||
3710 | if (rc != OK) break; /* Conditions loop */ | |
3711 | } | |
3712 | ||
3713 | ||
3714 | /* If the result is the one for which "message" and/or "log_message" are used, | |
3715 | handle the values of these modifiers. If there isn't a log message set, we make | |
3716 | it the same as the user message. | |
3717 | ||
3718 | "message" is a user message that will be included in an SMTP response. Unless | |
3719 | it is empty, it overrides any previously set user message. | |
3720 | ||
3721 | "log_message" is a non-user message, and it adds to any existing non-user | |
3722 | message that is already set. | |
3723 | ||
3724 | Most verbs have but a single return for which the messages are relevant, but | |
3725 | for "discard", it's useful to have the log message both when it succeeds and | |
3726 | when it fails. For "accept", the message is used in the OK case if there is no | |
3727 | "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is | |
3728 | present. */ | |
3729 | ||
3730 | if (*epp && rc == OK) user_message = NULL; | |
3731 | ||
3732 | if (((1<<rc) & msgcond[verb]) != 0) | |
3733 | { | |
3734 | uschar *expmessage; | |
3735 | uschar *old_user_msgptr = *user_msgptr; | |
3736 | uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr; | |
3737 | ||
3738 | /* If the verb is "warn", messages generated by conditions (verification or | |
3739 | nested ACLs) are always discarded. This also happens for acceptance verbs | |
3740 | when they actually do accept. Only messages specified at this level are used. | |
3741 | However, the value of an existing message is available in $acl_verify_message | |
3742 | during expansions. */ | |
3743 | ||
3744 | if (verb == ACL_WARN || | |
3745 | (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD))) | |
3746 | *log_msgptr = *user_msgptr = NULL; | |
3747 | ||
3748 | if (user_message != NULL) | |
3749 | { | |
3750 | acl_verify_message = old_user_msgptr; | |
3751 | expmessage = expand_string(user_message); | |
3752 | if (expmessage == NULL) | |
3753 | { | |
3754 | if (!expand_string_forcedfail) | |
3755 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s", | |
3756 | user_message, expand_string_message); | |
3757 | } | |
3758 | else if (expmessage[0] != 0) *user_msgptr = expmessage; | |
3759 | } | |
3760 | ||
3761 | if (log_message != NULL) | |
3762 | { | |
3763 | acl_verify_message = old_log_msgptr; | |
3764 | expmessage = expand_string(log_message); | |
3765 | if (expmessage == NULL) | |
3766 | { | |
3767 | if (!expand_string_forcedfail) | |
3768 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s", | |
3769 | log_message, expand_string_message); | |
3770 | } | |
3771 | else if (expmessage[0] != 0) | |
3772 | { | |
3773 | *log_msgptr = (*log_msgptr == NULL)? expmessage : | |
3774 | string_sprintf("%s: %s", expmessage, *log_msgptr); | |
3775 | } | |
3776 | } | |
3777 | ||
3778 | /* If no log message, default it to the user message */ | |
3779 | ||
3780 | if (*log_msgptr == NULL) *log_msgptr = *user_msgptr; | |
3781 | } | |
3782 | ||
3783 | acl_verify_message = NULL; | |
3784 | return rc; | |
3785 | } | |
3786 | ||
3787 | ||
3788 | ||
3789 | ||
3790 | ||
3791 | /************************************************* | |
3792 | * Get line from a literal ACL * | |
3793 | *************************************************/ | |
3794 | ||
3795 | /* This function is passed to acl_read() in order to extract individual lines | |
3796 | of a literal ACL, which we access via static pointers. We can destroy the | |
3797 | contents because this is called only once (the compiled ACL is remembered). | |
3798 | ||
3799 | This code is intended to treat the data in the same way as lines in the main | |
3800 | Exim configuration file. That is: | |
3801 | ||
3802 | . Leading spaces are ignored. | |
3803 | ||
3804 | . A \ at the end of a line is a continuation - trailing spaces after the \ | |
3805 | are permitted (this is because I don't believe in making invisible things | |
3806 | significant). Leading spaces on the continued part of a line are ignored. | |
3807 | ||
3808 | . Physical lines starting (significantly) with # are totally ignored, and | |
3809 | may appear within a sequence of backslash-continued lines. | |
3810 | ||
3811 | . Blank lines are ignored, but will end a sequence of continuations. | |
3812 | ||
3813 | Arguments: none | |
3814 | Returns: a pointer to the next line | |
3815 | */ | |
3816 | ||
3817 | ||
3818 | static uschar *acl_text; /* Current pointer in the text */ | |
3819 | static uschar *acl_text_end; /* Points one past the terminating '0' */ | |
3820 | ||
3821 | ||
3822 | static uschar * | |
3823 | acl_getline(void) | |
3824 | { | |
3825 | uschar *yield; | |
3826 | ||
3827 | /* This loop handles leading blank lines and comments. */ | |
3828 | ||
3829 | for(;;) | |
3830 | { | |
3831 | while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */ | |
3832 | if (*acl_text == 0) return NULL; /* No more data */ | |
3833 | yield = acl_text; /* Potential data line */ | |
3834 | ||
3835 | while (*acl_text != 0 && *acl_text != '\n') acl_text++; | |
3836 | ||
3837 | /* If we hit the end before a newline, we have the whole logical line. If | |
3838 | it's a comment, there's no more data to be given. Otherwise, yield it. */ | |
3839 | ||
3840 | if (*acl_text == 0) return (*yield == '#')? NULL : yield; | |
3841 | ||
3842 | /* After reaching a newline, end this loop if the physical line does not | |
3843 | start with '#'. If it does, it's a comment, and the loop continues. */ | |
3844 | ||
3845 | if (*yield != '#') break; | |
3846 | } | |
3847 | ||
3848 | /* This loop handles continuations. We know we have some real data, ending in | |
3849 | newline. See if there is a continuation marker at the end (ignoring trailing | |
3850 | white space). We know that *yield is not white space, so no need to test for | |
3851 | cont > yield in the backwards scanning loop. */ | |
3852 | ||
3853 | for(;;) | |
3854 | { | |
3855 | uschar *cont; | |
3856 | for (cont = acl_text - 1; isspace(*cont); cont--); | |
3857 | ||
3858 | /* If no continuation follows, we are done. Mark the end of the line and | |
3859 | return it. */ | |
3860 | ||
3861 | if (*cont != '\\') | |
3862 | { | |
3863 | *acl_text++ = 0; | |
3864 | return yield; | |
3865 | } | |
3866 | ||
3867 | /* We have encountered a continuation. Skip over whitespace at the start of | |
3868 | the next line, and indeed the whole of the next line or lines if they are | |
3869 | comment lines. */ | |
3870 | ||
3871 | for (;;) | |
3872 | { | |
3873 | while (*(++acl_text) == ' ' || *acl_text == '\t'); | |
3874 | if (*acl_text != '#') break; | |
3875 | while (*(++acl_text) != 0 && *acl_text != '\n'); | |
3876 | } | |
3877 | ||
3878 | /* We have the start of a continuation line. Move all the rest of the data | |
3879 | to join onto the previous line, and then find its end. If the end is not a | |
3880 | newline, we are done. Otherwise loop to look for another continuation. */ | |
3881 | ||
3882 | memmove(cont, acl_text, acl_text_end - acl_text); | |
3883 | acl_text_end -= acl_text - cont; | |
3884 | acl_text = cont; | |
3885 | while (*acl_text != 0 && *acl_text != '\n') acl_text++; | |
3886 | if (*acl_text == 0) return yield; | |
3887 | } | |
3888 | ||
3889 | /* Control does not reach here */ | |
3890 | } | |
3891 | ||
3892 | ||
3893 | ||
3894 | ||
3895 | ||
3896 | /************************************************* | |
3897 | * Check access using an ACL * | |
3898 | *************************************************/ | |
3899 | ||
3900 | /* This function is called from address_check. It may recurse via | |
3901 | acl_check_condition() - hence the use of a level to stop looping. The ACL is | |
3902 | passed as a string which is expanded. A forced failure implies no access check | |
3903 | is required. If the result is a single word, it is taken as the name of an ACL | |
3904 | which is sought in the global ACL tree. Otherwise, it is taken as literal ACL | |
3905 | text, complete with newlines, and parsed as such. In both cases, the ACL check | |
3906 | is then run. This function uses an auxiliary function for acl_read() to call | |
3907 | for reading individual lines of a literal ACL. This is acl_getline(), which | |
3908 | appears immediately above. | |
3909 | ||
3910 | Arguments: | |
3911 | where where called from | |
3912 | addr address item when called from RCPT; otherwise NULL | |
3913 | s the input string; NULL is the same as an empty ACL => DENY | |
3914 | level the nesting level | |
3915 | user_msgptr where to put a user error (for SMTP response) | |
3916 | log_msgptr where to put a logging message (not for SMTP response) | |
3917 | ||
3918 | Returns: OK access is granted | |
3919 | DISCARD access is apparently granted... | |
3920 | FAIL access is denied | |
3921 | FAIL_DROP access is denied; drop the connection | |
3922 | DEFER can't tell at the moment | |
3923 | ERROR disaster | |
3924 | */ | |
3925 | ||
3926 | static int | |
3927 | acl_check_internal(int where, address_item *addr, uschar *s, int level, | |
3928 | uschar **user_msgptr, uschar **log_msgptr) | |
3929 | { | |
3930 | int fd = -1; | |
3931 | acl_block *acl = NULL; | |
3932 | uschar *acl_name = US"inline ACL"; | |
3933 | uschar *ss; | |
3934 | ||
3935 | /* Catch configuration loops */ | |
3936 | ||
3937 | if (level > 20) | |
3938 | { | |
3939 | *log_msgptr = US"ACL nested too deep: possible loop"; | |
3940 | return ERROR; | |
3941 | } | |
3942 | ||
3943 | if (s == NULL) | |
3944 | { | |
3945 | HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n"); | |
3946 | return FAIL; | |
3947 | } | |
3948 | ||
3949 | /* At top level, we expand the incoming string. At lower levels, it has already | |
3950 | been expanded as part of condition processing. */ | |
3951 | ||
3952 | if (level == 0) | |
3953 | { | |
3954 | ss = expand_string(s); | |
3955 | if (ss == NULL) | |
3956 | { | |
3957 | if (expand_string_forcedfail) return OK; | |
3958 | *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s, | |
3959 | expand_string_message); | |
3960 | return ERROR; | |
3961 | } | |
3962 | } | |
3963 | else ss = s; | |
3964 | ||
3965 | while (isspace(*ss))ss++; | |
3966 | ||
3967 | /* If we can't find a named ACL, the default is to parse it as an inline one. | |
3968 | (Unless it begins with a slash; non-existent files give rise to an error.) */ | |
3969 | ||
3970 | acl_text = ss; | |
3971 | ||
3972 | /* Handle the case of a string that does not contain any spaces. Look for a | |
3973 | named ACL among those read from the configuration, or a previously read file. | |
3974 | It is possible that the pointer to the ACL is NULL if the configuration | |
3975 | contains a name with no data. If not found, and the text begins with '/', | |
3976 | read an ACL from a file, and save it so it can be re-used. */ | |
3977 | ||
3978 | if (Ustrchr(ss, ' ') == NULL) | |
3979 | { | |
3980 | tree_node *t = tree_search(acl_anchor, ss); | |
3981 | if (t != NULL) | |
3982 | { | |
3983 | acl = (acl_block *)(t->data.ptr); | |
3984 | if (acl == NULL) | |
3985 | { | |
3986 | HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss); | |
3987 | return FAIL; | |
3988 | } | |
3989 | acl_name = string_sprintf("ACL \"%s\"", ss); | |
3990 | HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss); | |
3991 | } | |
3992 | ||
3993 | else if (*ss == '/') | |
3994 | { | |
3995 | struct stat statbuf; | |
3996 | fd = Uopen(ss, O_RDONLY, 0); | |
3997 | if (fd < 0) | |
3998 | { | |
3999 | *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss, | |
4000 | strerror(errno)); | |
4001 | return ERROR; | |
4002 | } | |
4003 | ||
4004 | if (fstat(fd, &statbuf) != 0) | |
4005 | { | |
4006 | *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss, | |
4007 | strerror(errno)); | |
4008 | return ERROR; | |
4009 | } | |
4010 | ||
4011 | acl_text = store_get(statbuf.st_size + 1); | |
4012 | acl_text_end = acl_text + statbuf.st_size + 1; | |
4013 | ||
4014 | if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size) | |
4015 | { | |
4016 | *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s", | |
4017 | ss, strerror(errno)); | |
4018 | return ERROR; | |
4019 | } | |
4020 | acl_text[statbuf.st_size] = 0; | |
4021 | (void)close(fd); | |
4022 | ||
4023 | acl_name = string_sprintf("ACL \"%s\"", ss); | |
4024 | HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss); | |
4025 | } | |
4026 | } | |
4027 | ||
4028 | /* Parse an ACL that is still in text form. If it came from a file, remember it | |
4029 | in the ACL tree, having read it into the POOL_PERM store pool so that it | |
4030 | persists between multiple messages. */ | |
4031 | ||
4032 | if (acl == NULL) | |
4033 | { | |
4034 | int old_pool = store_pool; | |
4035 | if (fd >= 0) store_pool = POOL_PERM; | |
4036 | acl = acl_read(acl_getline, log_msgptr); | |
4037 | store_pool = old_pool; | |
4038 | if (acl == NULL && *log_msgptr != NULL) return ERROR; | |
4039 | if (fd >= 0) | |
4040 | { | |
4041 | tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss)); | |
4042 | Ustrcpy(t->name, ss); | |
4043 | t->data.ptr = acl; | |
4044 | (void)tree_insertnode(&acl_anchor, t); | |
4045 | } | |
4046 | } | |
4047 | ||
4048 | /* Now we have an ACL to use. It's possible it may be NULL. */ | |
4049 | ||
4050 | while (acl != NULL) | |
4051 | { | |
4052 | int cond; | |
4053 | int basic_errno = 0; | |
4054 | BOOL endpass_seen = FALSE; | |
4055 | ||
4056 | *log_msgptr = *user_msgptr = NULL; | |
4057 | acl_temp_details = FALSE; | |
4058 | ||
4059 | if ((where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT) && | |
4060 | acl->verb != ACL_ACCEPT && | |
4061 | acl->verb != ACL_WARN) | |
4062 | { | |
4063 | *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT or not-QUIT ACL", | |
4064 | verbs[acl->verb]); | |
4065 | return ERROR; | |
4066 | } | |
4067 | ||
4068 | HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]); | |
4069 | ||
4070 | /* Clear out any search error message from a previous check before testing | |
4071 | this condition. */ | |
4072 | ||
4073 | search_error_message = NULL; | |
4074 | cond = acl_check_condition(acl->verb, acl->condition, where, addr, level, | |
4075 | &endpass_seen, user_msgptr, log_msgptr, &basic_errno); | |
4076 | ||
4077 | /* Handle special returns: DEFER causes a return except on a WARN verb; | |
4078 | ERROR always causes a return. */ | |
4079 | ||
4080 | switch (cond) | |
4081 | { | |
4082 | case DEFER: | |
4083 | HDEBUG(D_acl) debug_printf("%s: condition test deferred in %s\n", verbs[acl->verb], acl_name); | |
4084 | if (basic_errno != ERRNO_CALLOUTDEFER) | |
4085 | { | |
4086 | if (search_error_message != NULL && *search_error_message != 0) | |
4087 | *log_msgptr = search_error_message; | |
4088 | if (smtp_return_error_details) acl_temp_details = TRUE; | |
4089 | } | |
4090 | else | |
4091 | { | |
4092 | acl_temp_details = TRUE; | |
4093 | } | |
4094 | if (acl->verb != ACL_WARN) return DEFER; | |
4095 | break; | |
4096 | ||
4097 | default: /* Paranoia */ | |
4098 | case ERROR: | |
4099 | HDEBUG(D_acl) debug_printf("%s: condition test error in %s\n", verbs[acl->verb], acl_name); | |
4100 | return ERROR; | |
4101 | ||
4102 | case OK: | |
4103 | HDEBUG(D_acl) debug_printf("%s: condition test succeeded in %s\n", | |
4104 | verbs[acl->verb], acl_name); | |
4105 | break; | |
4106 | ||
4107 | case FAIL: | |
4108 | HDEBUG(D_acl) debug_printf("%s: condition test failed in %s\n", verbs[acl->verb], acl_name); | |
4109 | break; | |
4110 | ||
4111 | /* DISCARD and DROP can happen only from a nested ACL condition, and | |
4112 | DISCARD can happen only for an "accept" or "discard" verb. */ | |
4113 | ||
4114 | case DISCARD: | |
4115 | HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\" in %s\n", | |
4116 | verbs[acl->verb], acl_name); | |
4117 | break; | |
4118 | ||
4119 | case FAIL_DROP: | |
4120 | HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\" in %s\n", | |
4121 | verbs[acl->verb], acl_name); | |
4122 | break; | |
4123 | } | |
4124 | ||
4125 | /* At this point, cond for most verbs is either OK or FAIL or (as a result of | |
4126 | a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and | |
4127 | for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */ | |
4128 | ||
4129 | switch(acl->verb) | |
4130 | { | |
4131 | case ACL_ACCEPT: | |
4132 | if (cond == OK || cond == DISCARD) return cond; | |
4133 | if (endpass_seen) | |
4134 | { | |
4135 | HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n"); | |
4136 | return cond; | |
4137 | } | |
4138 | break; | |
4139 | ||
4140 | case ACL_DEFER: | |
4141 | if (cond == OK) | |
4142 | { | |
4143 | acl_temp_details = TRUE; | |
4144 | return DEFER; | |
4145 | } | |
4146 | break; | |
4147 | ||
4148 | case ACL_DENY: | |
4149 | if (cond == OK) return FAIL; | |
4150 | break; | |
4151 | ||
4152 | case ACL_DISCARD: | |
4153 | if (cond == OK || cond == DISCARD) return DISCARD; | |
4154 | if (endpass_seen) | |
4155 | { | |
4156 | HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n"); | |
4157 | return cond; | |
4158 | } | |
4159 | break; | |
4160 | ||
4161 | case ACL_DROP: | |
4162 | if (cond == OK) return FAIL_DROP; | |
4163 | break; | |
4164 | ||
4165 | case ACL_REQUIRE: | |
4166 | if (cond != OK) return cond; | |
4167 | break; | |
4168 | ||
4169 | case ACL_WARN: | |
4170 | if (cond == OK) | |
4171 | acl_warn(where, *user_msgptr, *log_msgptr); | |
4172 | else if (cond == DEFER && (log_extra_selector & LX_acl_warn_skipped) != 0) | |
4173 | log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: " | |
4174 | "condition test deferred%s%s", host_and_ident(TRUE), | |
4175 | (*log_msgptr == NULL)? US"" : US": ", | |
4176 | (*log_msgptr == NULL)? US"" : *log_msgptr); | |
4177 | *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */ | |
4178 | break; | |
4179 | ||
4180 | default: | |
4181 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d", | |
4182 | acl->verb); | |
4183 | break; | |
4184 | } | |
4185 | ||
4186 | /* Pass to the next ACL item */ | |
4187 | ||
4188 | acl = acl->next; | |
4189 | } | |
4190 | ||
4191 | /* We have reached the end of the ACL. This is an implicit DENY. */ | |
4192 | ||
4193 | HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name); | |
4194 | return FAIL; | |
4195 | } | |
4196 | ||
4197 | ||
4198 | ||
4199 | ||
4200 | /* Same args as acl_check_internal() above, but the string s is | |
4201 | the name of an ACL followed optionally by up to 9 space-separated arguments. | |
4202 | The name and args are separately expanded. Args go into $acl_arg globals. */ | |
4203 | static int | |
4204 | acl_check_wargs(int where, address_item *addr, uschar *s, int level, | |
4205 | uschar **user_msgptr, uschar **log_msgptr) | |
4206 | { | |
4207 | uschar * tmp; | |
4208 | uschar * tmp_arg[9]; /* must match acl_arg[] */ | |
4209 | uschar * sav_arg[9]; /* must match acl_arg[] */ | |
4210 | int sav_narg; | |
4211 | uschar * name; | |
4212 | int i; | |
4213 | int ret; | |
4214 | ||
4215 | if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp))) | |
4216 | goto bad; | |
4217 | ||
4218 | for (i = 0; i < 9; i++) | |
4219 | { | |
4220 | while (*s && isspace(*s)) s++; | |
4221 | if (!*s) break; | |
4222 | if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp))) | |
4223 | { | |
4224 | tmp = name; | |
4225 | goto bad; | |
4226 | } | |
4227 | } | |
4228 | ||
4229 | sav_narg = acl_narg; | |
4230 | acl_narg = i; | |
4231 | for (i = 0; i < acl_narg; i++) | |
4232 | { | |
4233 | sav_arg[i] = acl_arg[i]; | |
4234 | acl_arg[i] = tmp_arg[i]; | |
4235 | } | |
4236 | while (i < 9) | |
4237 | { | |
4238 | sav_arg[i] = acl_arg[i]; | |
4239 | acl_arg[i++] = NULL; | |
4240 | } | |
4241 | ||
4242 | ret = acl_check_internal(where, addr, name, level, user_msgptr, log_msgptr); | |
4243 | ||
4244 | acl_narg = sav_narg; | |
4245 | for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i]; | |
4246 | return ret; | |
4247 | ||
4248 | bad: | |
4249 | if (expand_string_forcedfail) return ERROR; | |
4250 | *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", | |
4251 | tmp, expand_string_message); | |
4252 | return search_find_defer?DEFER:ERROR; | |
4253 | } | |
4254 | ||
4255 | ||
4256 | ||
4257 | /************************************************* | |
4258 | * Check access using an ACL * | |
4259 | *************************************************/ | |
4260 | ||
4261 | /* Alternate interface for ACL, used by expansions */ | |
4262 | int | |
4263 | acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr) | |
4264 | { | |
4265 | address_item adb; | |
4266 | address_item *addr = NULL; | |
4267 | ||
4268 | *user_msgptr = *log_msgptr = NULL; | |
4269 | sender_verified_failed = NULL; | |
4270 | ratelimiters_cmd = NULL; | |
4271 | log_reject_target = LOG_MAIN|LOG_REJECT; | |
4272 | ||
4273 | if (where == ACL_WHERE_RCPT) | |
4274 | { | |
4275 | adb = address_defaults; | |
4276 | addr = &adb; | |
4277 | addr->address = expand_string(US"$local_part@$domain"); | |
4278 | addr->domain = deliver_domain; | |
4279 | addr->local_part = deliver_localpart; | |
4280 | addr->cc_local_part = deliver_localpart; | |
4281 | addr->lc_local_part = deliver_localpart; | |
4282 | } | |
4283 | ||
4284 | return acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr); | |
4285 | } | |
4286 | ||
4287 | ||
4288 | ||
4289 | /* This is the external interface for ACL checks. It sets up an address and the | |
4290 | expansions for $domain and $local_part when called after RCPT, then calls | |
4291 | acl_check_internal() to do the actual work. | |
4292 | ||
4293 | Arguments: | |
4294 | where ACL_WHERE_xxxx indicating where called from | |
4295 | recipient RCPT address for RCPT check, else NULL | |
4296 | s the input string; NULL is the same as an empty ACL => DENY | |
4297 | user_msgptr where to put a user error (for SMTP response) | |
4298 | log_msgptr where to put a logging message (not for SMTP response) | |
4299 | ||
4300 | Returns: OK access is granted by an ACCEPT verb | |
4301 | DISCARD access is granted by a DISCARD verb | |
4302 | FAIL access is denied | |
4303 | FAIL_DROP access is denied; drop the connection | |
4304 | DEFER can't tell at the moment | |
4305 | ERROR disaster | |
4306 | */ | |
4307 | int acl_where = ACL_WHERE_UNKNOWN; | |
4308 | ||
4309 | int | |
4310 | acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr, | |
4311 | uschar **log_msgptr) | |
4312 | { | |
4313 | int rc; | |
4314 | address_item adb; | |
4315 | address_item *addr = NULL; | |
4316 | ||
4317 | *user_msgptr = *log_msgptr = NULL; | |
4318 | sender_verified_failed = NULL; | |
4319 | ratelimiters_cmd = NULL; | |
4320 | log_reject_target = LOG_MAIN|LOG_REJECT; | |
4321 | ||
4322 | #ifndef DISABLE_PRDR | |
4323 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_PRDR ) | |
4324 | #else | |
4325 | if (where == ACL_WHERE_RCPT ) | |
4326 | #endif | |
4327 | { | |
4328 | adb = address_defaults; | |
4329 | addr = &adb; | |
4330 | addr->address = recipient; | |
4331 | if (deliver_split_address(addr) == DEFER) | |
4332 | { | |
4333 | *log_msgptr = US"defer in percent_hack_domains check"; | |
4334 | return DEFER; | |
4335 | } | |
4336 | deliver_domain = addr->domain; | |
4337 | deliver_localpart = addr->local_part; | |
4338 | } | |
4339 | ||
4340 | acl_where = where; | |
4341 | rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr); | |
4342 | acl_where = ACL_WHERE_UNKNOWN; | |
4343 | ||
4344 | /* Cutthrough - if requested, | |
4345 | and WHERE_RCPT and not yet opened conn as result of recipient-verify, | |
4346 | and rcpt acl returned accept, | |
4347 | and first recipient (cancel on any subsequents) | |
4348 | open one now and run it up to RCPT acceptance. | |
4349 | A failed verify should cancel cutthrough request. | |
4350 | ||
4351 | Initial implementation: dual-write to spool. | |
4352 | Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection. | |
4353 | ||
4354 | Cease cutthrough copy on rxd final dot; do not send one. | |
4355 | ||
4356 | On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness). | |
4357 | ||
4358 | On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or | |
4359 | perm-rejected, reflect that to the original sender - and dump the spooled copy. | |
4360 | If temp-reject, close the conn (and keep the spooled copy). | |
4361 | If conn-failure, no action (and keep the spooled copy). | |
4362 | */ | |
4363 | switch (where) | |
4364 | { | |
4365 | case ACL_WHERE_RCPT: | |
4366 | #ifndef DISABLE_PRDR | |
4367 | case ACL_WHERE_PRDR: | |
4368 | #endif | |
4369 | if( rcpt_count > 1 ) | |
4370 | cancel_cutthrough_connection("more than one recipient"); | |
4371 | else if (rc == OK && cutthrough_delivery && cutthrough_fd < 0) | |
4372 | open_cutthrough_connection(addr); | |
4373 | break; | |
4374 | ||
4375 | case ACL_WHERE_PREDATA: | |
4376 | if( rc == OK ) | |
4377 | cutthrough_predata(); | |
4378 | else | |
4379 | cancel_cutthrough_connection("predata acl not ok"); | |
4380 | break; | |
4381 | ||
4382 | case ACL_WHERE_QUIT: | |
4383 | case ACL_WHERE_NOTQUIT: | |
4384 | cancel_cutthrough_connection("quit or notquit"); | |
4385 | break; | |
4386 | ||
4387 | default: | |
4388 | break; | |
4389 | } | |
4390 | ||
4391 | deliver_domain = deliver_localpart = deliver_address_data = | |
4392 | sender_address_data = NULL; | |
4393 | ||
4394 | /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA | |
4395 | ACL, which is really in the middle of an SMTP command. */ | |
4396 | ||
4397 | if (rc == DISCARD) | |
4398 | { | |
4399 | if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA) | |
4400 | { | |
4401 | log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s " | |
4402 | "ACL", acl_wherenames[where]); | |
4403 | return ERROR; | |
4404 | } | |
4405 | return DISCARD; | |
4406 | } | |
4407 | ||
4408 | /* A DROP response is not permitted from MAILAUTH */ | |
4409 | ||
4410 | if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH) | |
4411 | { | |
4412 | log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s " | |
4413 | "ACL", acl_wherenames[where]); | |
4414 | return ERROR; | |
4415 | } | |
4416 | ||
4417 | /* Before giving a response, take a look at the length of any user message, and | |
4418 | split it up into multiple lines if possible. */ | |
4419 | ||
4420 | *user_msgptr = string_split_message(*user_msgptr); | |
4421 | if (fake_response != OK) | |
4422 | fake_response_text = string_split_message(fake_response_text); | |
4423 | ||
4424 | return rc; | |
4425 | } | |
4426 | ||
4427 | ||
4428 | /************************************************* | |
4429 | * Create ACL variable * | |
4430 | *************************************************/ | |
4431 | ||
4432 | /* Create an ACL variable or reuse an existing one. ACL variables are in a | |
4433 | binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes. | |
4434 | ||
4435 | Argument: | |
4436 | name pointer to the variable's name, starting with c or m | |
4437 | ||
4438 | Returns the pointer to variable's tree node | |
4439 | */ | |
4440 | ||
4441 | tree_node * | |
4442 | acl_var_create(uschar *name) | |
4443 | { | |
4444 | tree_node *node, **root; | |
4445 | root = (name[0] == 'c')? &acl_var_c : &acl_var_m; | |
4446 | node = tree_search(*root, name); | |
4447 | if (node == NULL) | |
4448 | { | |
4449 | node = store_get(sizeof(tree_node) + Ustrlen(name)); | |
4450 | Ustrcpy(node->name, name); | |
4451 | (void)tree_insertnode(root, node); | |
4452 | } | |
4453 | node->data.ptr = NULL; | |
4454 | return node; | |
4455 | } | |
4456 | ||
4457 | ||
4458 | ||
4459 | /************************************************* | |
4460 | * Write an ACL variable in spool format * | |
4461 | *************************************************/ | |
4462 | ||
4463 | /* This function is used as a callback for tree_walk when writing variables to | |
4464 | the spool file. To retain spool file compatibility, what is written is -aclc or | |
4465 | -aclm followed by the rest of the name and the data length, space separated, | |
4466 | then the value itself, starting on a new line, and terminated by an additional | |
4467 | newline. When we had only numbered ACL variables, the first line might look | |
4468 | like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called | |
4469 | acl_cfoo. | |
4470 | ||
4471 | Arguments: | |
4472 | name of the variable | |
4473 | value of the variable | |
4474 | ctx FILE pointer (as a void pointer) | |
4475 | ||
4476 | Returns: nothing | |
4477 | */ | |
4478 | ||
4479 | void | |
4480 | acl_var_write(uschar *name, uschar *value, void *ctx) | |
4481 | { | |
4482 | FILE *f = (FILE *)ctx; | |
4483 | fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value); | |
4484 | } | |
4485 | ||
4486 | /* vi: aw ai sw=2 | |
4487 | */ | |
4488 | /* End of acl.c */ |