1 /* $Cambridge: exim/src/src/acl.c,v 1.69 2007/01/30 11:45:20 ph10 Exp $ */
3 /*************************************************
4 * Exim - an Internet mail transport agent *
5 *************************************************/
7 /* Copyright (c) University of Cambridge 1995 - 2007 */
8 /* See the file NOTICE for conditions of use and distribution. */
10 /* Code for handling Access Control Lists (ACLs) */
15 /* Default callout timeout */
17 #define CALLOUT_TIMEOUT_DEFAULT 30
19 /* ACL verb codes - keep in step with the table of verbs that follows */
21 enum { ACL_ACCEPT
, ACL_DEFER
, ACL_DENY
, ACL_DISCARD
, ACL_DROP
, ACL_REQUIRE
,
26 static uschar
*verbs
[] =
27 { US
"accept", US
"defer", US
"deny", US
"discard", US
"drop", US
"require",
30 /* For each verb, the conditions for which "message" or "log_message" are used
31 are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
32 "accept", the FAIL case is used only after "endpass", but that is selected in
35 static int msgcond
[] = {
36 (1<<OK
) | (1<<FAIL
) | (1<<FAIL_DROP
), /* accept */
39 (1<<OK
) | (1<<FAIL
) | (1<<FAIL_DROP
), /* discard */
41 (1<<FAIL
) | (1<<FAIL_DROP
), /* require */
45 /* ACL condition and modifier codes - keep in step with the table that
46 follows, and the cond_expand_at_top and uschar cond_modifiers tables lower
52 #ifdef EXPERIMENTAL_BRIGHTMAIL
57 #ifdef WITH_CONTENT_SCAN
61 #ifdef WITH_OLD_DEMIME
64 #ifdef EXPERIMENTAL_DOMAINKEYS
65 ACLC_DK_DOMAIN_SOURCE
,
67 ACLC_DK_SENDER_DOMAINS
,
68 ACLC_DK_SENDER_LOCAL_PARTS
,
79 ACLC_LOG_REJECT_TARGET
,
81 #ifdef WITH_CONTENT_SCAN
85 #ifdef WITH_CONTENT_SCAN
90 #ifdef WITH_CONTENT_SCAN
96 #ifdef WITH_CONTENT_SCAN
99 #ifdef EXPERIMENTAL_SPF
104 /* ACL conditions/modifiers: "delay", "control", "endpass", "message",
105 "log_message", "log_reject_target", "logwrite", and "set" are modifiers that
106 look like conditions but always return TRUE. They are used for their side
109 static uschar
*conditions
[] = {
113 #ifdef EXPERIMENTAL_BRIGHTMAIL
118 #ifdef WITH_CONTENT_SCAN
122 #ifdef WITH_OLD_DEMIME
125 #ifdef EXPERIMENTAL_DOMAINKEYS
126 US
"dk_domain_source",
128 US
"dk_sender_domains",
129 US
"dk_sender_local_parts",
140 US
"log_reject_target",
142 #ifdef WITH_CONTENT_SCAN
146 #ifdef WITH_CONTENT_SCAN
151 #ifdef WITH_CONTENT_SCAN
154 US
"sender_domains", US
"senders", US
"set",
155 #ifdef WITH_CONTENT_SCAN
158 #ifdef EXPERIMENTAL_SPF
164 /* Return values from decode_control(); keep in step with the table of names
168 CONTROL_AUTH_UNADVERTISED
,
169 #ifdef EXPERIMENTAL_BRIGHTMAIL
172 #ifdef EXPERIMENTAL_DOMAINKEYS
176 CONTROL_CASEFUL_LOCAL_PART
,
177 CONTROL_CASELOWER_LOCAL_PART
,
178 CONTROL_ENFORCE_SYNC
,
179 CONTROL_NO_ENFORCE_SYNC
,
183 CONTROL_SUPPRESS_LOCAL_FIXUPS
,
184 #ifdef WITH_CONTENT_SCAN
185 CONTROL_NO_MBOX_UNSPOOL
,
189 CONTROL_NO_MULTILINE
,
190 CONTROL_NO_PIPELINING
193 /* ACL control names; keep in step with the table above! This list is used for
194 turning ids into names. The actual list of recognized names is in the variable
195 control_def controls_list[] below. The fact that there are two lists is a mess
196 and should be tidied up. */
198 static uschar
*controls
[] = {
199 US
"allow_auth_unadvertised",
200 #ifdef EXPERIMENTAL_BRIGHTMAIL
203 #ifdef EXPERIMENTAL_DOMAINKEYS
207 US
"caseful_local_part",
208 US
"caselower_local_part",
214 US
"suppress_local_fixups",
215 #ifdef WITH_CONTENT_SCAN
224 /* Flags to indicate for which conditions /modifiers a string expansion is done
225 at the outer level. In the other cases, expansion already occurs in the
226 checking functions. */
228 static uschar cond_expand_at_top
[] = {
230 TRUE
, /* add_header */
231 FALSE
, /* authenticated */
232 #ifdef EXPERIMENTAL_BRIGHTMAIL
233 TRUE
, /* bmi_optin */
235 TRUE
, /* condition */
237 #ifdef WITH_CONTENT_SCAN
241 #ifdef WITH_OLD_DEMIME
244 #ifdef EXPERIMENTAL_DOMAINKEYS
245 TRUE
, /* dk_domain_source */
246 TRUE
, /* dk_policy */
247 TRUE
, /* dk_sender_domains */
248 TRUE
, /* dk_sender_local_parts */
249 TRUE
, /* dk_senders */
250 TRUE
, /* dk_status */
254 FALSE
, /* encrypted */
257 FALSE
, /* local_parts */
258 TRUE
, /* log_message */
259 TRUE
, /* log_reject_target */
261 #ifdef WITH_CONTENT_SCAN
265 #ifdef WITH_CONTENT_SCAN
266 TRUE
, /* mime_regex */
268 TRUE
, /* ratelimit */
269 FALSE
, /* recipients */
270 #ifdef WITH_CONTENT_SCAN
273 FALSE
, /* sender_domains */
276 #ifdef WITH_CONTENT_SCAN
279 #ifdef EXPERIMENTAL_SPF
285 /* Flags to identify the modifiers */
287 static uschar cond_modifiers
[] = {
289 TRUE
, /* add_header */
290 FALSE
, /* authenticated */
291 #ifdef EXPERIMENTAL_BRIGHTMAIL
292 TRUE
, /* bmi_optin */
294 FALSE
, /* condition */
296 #ifdef WITH_CONTENT_SCAN
300 #ifdef WITH_OLD_DEMIME
303 #ifdef EXPERIMENTAL_DOMAINKEYS
304 FALSE
, /* dk_domain_source */
305 FALSE
, /* dk_policy */
306 FALSE
, /* dk_sender_domains */
307 FALSE
, /* dk_sender_local_parts */
308 FALSE
, /* dk_senders */
309 FALSE
, /* dk_status */
311 FALSE
, /* dnslists */
313 FALSE
, /* encrypted */
316 FALSE
, /* local_parts */
317 TRUE
, /* log_message */
318 TRUE
, /* log_reject_target */
320 #ifdef WITH_CONTENT_SCAN
324 #ifdef WITH_CONTENT_SCAN
325 FALSE
, /* mime_regex */
327 FALSE
, /* ratelimit */
328 FALSE
, /* recipients */
329 #ifdef WITH_CONTENT_SCAN
332 FALSE
, /* sender_domains */
335 #ifdef WITH_CONTENT_SCAN
338 #ifdef EXPERIMENTAL_SPF
344 /* Bit map vector of which conditions are not allowed at certain times. For
345 each condition, there's a bitmap of dis-allowed times. For some, it is easier
346 to specify the negation of a small number of allowed times. */
348 static unsigned int cond_forbids
[] = {
352 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* add_header */
353 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
354 (1<<ACL_WHERE_MIME
)|(1<<ACL_WHERE_NOTSMTP
)|
355 (1<<ACL_WHERE_NOTSMTP_START
)),
357 (1<<ACL_WHERE_NOTSMTP
)| /* authenticated */
358 (1<<ACL_WHERE_NOTSMTP_START
)|
359 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
),
361 #ifdef EXPERIMENTAL_BRIGHTMAIL
362 (1<<ACL_WHERE_AUTH
)| /* bmi_optin */
363 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
364 (1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_MIME
)|
365 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
366 (1<<ACL_WHERE_MAILAUTH
)|
367 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
368 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_PREDATA
)|
369 (1<<ACL_WHERE_NOTSMTP_START
),
374 /* Certain types of control are always allowed, so we let it through
375 always and check in the control processing itself. */
379 #ifdef WITH_CONTENT_SCAN
381 ~(1<<ACL_WHERE_MIME
), /* decode */
386 #ifdef WITH_OLD_DEMIME
388 ~((1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_NOTSMTP
)), /* demime */
391 #ifdef EXPERIMENTAL_DOMAINKEYS
392 (1<<ACL_WHERE_AUTH
)| /* dk_domain_source */
393 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
394 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
395 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
396 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
397 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
398 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
400 (1<<ACL_WHERE_AUTH
)| /* dk_policy */
401 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
402 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
403 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
404 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
405 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
406 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
408 (1<<ACL_WHERE_AUTH
)| /* dk_sender_domains */
409 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
410 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
411 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
412 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
413 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
414 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
416 (1<<ACL_WHERE_AUTH
)| /* dk_sender_local_parts */
417 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
418 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
419 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
420 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
421 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
422 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
424 (1<<ACL_WHERE_AUTH
)| /* dk_senders */
425 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
426 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
427 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
428 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
429 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
430 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
432 (1<<ACL_WHERE_AUTH
)| /* dk_status */
433 (1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)|
434 (1<<ACL_WHERE_RCPT
)|(1<<ACL_WHERE_PREDATA
)|
435 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
436 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
437 (1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_STARTTLS
)|
438 (1<<ACL_WHERE_VRFY
)|(1<<ACL_WHERE_NOTSMTP_START
),
441 (1<<ACL_WHERE_NOTSMTP
)| /* dnslists */
442 (1<<ACL_WHERE_NOTSMTP_START
),
445 ~(1<<ACL_WHERE_RCPT
), /* domains */
447 (1<<ACL_WHERE_NOTSMTP
)| /* encrypted */
448 (1<<ACL_WHERE_CONNECT
)|
449 (1<<ACL_WHERE_NOTSMTP_START
)|
454 (1<<ACL_WHERE_NOTSMTP
)| /* hosts */
455 (1<<ACL_WHERE_NOTSMTP_START
),
458 ~(1<<ACL_WHERE_RCPT
), /* local_parts */
462 0, /* log_reject_target */
466 #ifdef WITH_CONTENT_SCAN
468 ~((1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_NOTSMTP
)), /* malware */
473 #ifdef WITH_CONTENT_SCAN
475 ~(1<<ACL_WHERE_MIME
), /* mime_regex */
481 ~(1<<ACL_WHERE_RCPT
), /* recipients */
483 #ifdef WITH_CONTENT_SCAN
485 ~((1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_NOTSMTP
)| /* regex */
486 (1<<ACL_WHERE_MIME
)),
489 (1<<ACL_WHERE_AUTH
)|(1<<ACL_WHERE_CONNECT
)| /* sender_domains */
491 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
492 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
493 (1<<ACL_WHERE_STARTTLS
)|(1<<ACL_WHERE_VRFY
),
495 (1<<ACL_WHERE_AUTH
)|(1<<ACL_WHERE_CONNECT
)| /* senders */
497 (1<<ACL_WHERE_MAILAUTH
)|(1<<ACL_WHERE_QUIT
)|
498 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
499 (1<<ACL_WHERE_STARTTLS
)|(1<<ACL_WHERE_VRFY
),
503 #ifdef WITH_CONTENT_SCAN
505 ~((1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_NOTSMTP
)), /* spam */
508 #ifdef EXPERIMENTAL_SPF
509 (1<<ACL_WHERE_AUTH
)|(1<<ACL_WHERE_CONNECT
)| /* spf */
511 (1<<ACL_WHERE_MAILAUTH
)|
512 (1<<ACL_WHERE_ETRN
)|(1<<ACL_WHERE_EXPN
)|
513 (1<<ACL_WHERE_STARTTLS
)|(1<<ACL_WHERE_VRFY
)|
514 (1<<ACL_WHERE_NOTSMTP
)|
515 (1<<ACL_WHERE_NOTSMTP_START
),
518 /* Certain types of verify are always allowed, so we let it through
519 always and check in the verify function itself */
525 /* Bit map vector of which controls are not allowed at certain times. For
526 each control, there's a bitmap of dis-allowed times. For some, it is easier to
527 specify the negation of a small number of allowed times. */
529 static unsigned int control_forbids
[] = {
531 ~((1<<ACL_WHERE_CONNECT
)|(1<<ACL_WHERE_HELO
)), /* allow_auth_unadvertised */
533 #ifdef EXPERIMENTAL_BRIGHTMAIL
537 #ifdef EXPERIMENTAL_DOMAINKEYS
538 (1<<ACL_WHERE_DATA
)|(1<<ACL_WHERE_NOTSMTP
)| /* dk_verify */
539 (1<<ACL_WHERE_NOTSMTP_START
),
545 ~(1<<ACL_WHERE_RCPT
), /* caseful_local_part */
548 ~(1<<ACL_WHERE_RCPT
), /* caselower_local_part */
550 (1<<ACL_WHERE_NOTSMTP
)| /* enforce_sync */
551 (1<<ACL_WHERE_NOTSMTP_START
),
553 (1<<ACL_WHERE_NOTSMTP
)| /* no_enforce_sync */
554 (1<<ACL_WHERE_NOTSMTP_START
),
557 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* freeze */
558 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
559 (1<<ACL_WHERE_NOTSMTP
)|(1<<ACL_WHERE_MIME
)),
562 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* queue_only */
563 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
564 (1<<ACL_WHERE_NOTSMTP
)|(1<<ACL_WHERE_MIME
)),
567 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* submission */
568 (1<<ACL_WHERE_PREDATA
)),
571 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* suppress_local_fixups */
572 (1<<ACL_WHERE_PREDATA
)|
573 (1<<ACL_WHERE_NOTSMTP_START
)),
575 #ifdef WITH_CONTENT_SCAN
577 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* no_mbox_unspool */
578 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
579 (1<<ACL_WHERE_MIME
)),
583 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* fakedefer */
584 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
585 (1<<ACL_WHERE_MIME
)),
588 ~((1<<ACL_WHERE_MAIL
)|(1<<ACL_WHERE_RCPT
)| /* fakereject */
589 (1<<ACL_WHERE_PREDATA
)|(1<<ACL_WHERE_DATA
)|
590 (1<<ACL_WHERE_MIME
)),
592 (1<<ACL_WHERE_NOTSMTP
)| /* no_multiline */
593 (1<<ACL_WHERE_NOTSMTP_START
),
595 (1<<ACL_WHERE_NOTSMTP
)| /* no_pipelining */
596 (1<<ACL_WHERE_NOTSMTP_START
)
599 /* Structure listing various control arguments, with their characteristics. */
601 typedef struct control_def
{
603 int value
; /* CONTROL_xxx value */
604 BOOL has_option
; /* Has /option(s) following */
607 static control_def controls_list
[] = {
608 { US
"allow_auth_unadvertised", CONTROL_AUTH_UNADVERTISED
, FALSE
},
609 #ifdef EXPERIMENTAL_BRIGHTMAIL
610 { US
"bmi_run", CONTROL_BMI_RUN
, FALSE
},
612 #ifdef EXPERIMENTAL_DOMAINKEYS
613 { US
"dk_verify", CONTROL_DK_VERIFY
, FALSE
},
615 { US
"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART
, FALSE
},
616 { US
"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART
, FALSE
},
617 { US
"enforce_sync", CONTROL_ENFORCE_SYNC
, FALSE
},
618 { US
"freeze", CONTROL_FREEZE
, TRUE
},
619 { US
"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC
, FALSE
},
620 { US
"no_multiline_responses", CONTROL_NO_MULTILINE
, FALSE
},
621 { US
"no_pipelining", CONTROL_NO_PIPELINING
, FALSE
},
622 { US
"queue_only", CONTROL_QUEUE_ONLY
, FALSE
},
623 #ifdef WITH_CONTENT_SCAN
624 { US
"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL
, FALSE
},
626 { US
"fakedefer", CONTROL_FAKEDEFER
, TRUE
},
627 { US
"fakereject", CONTROL_FAKEREJECT
, TRUE
},
628 { US
"submission", CONTROL_SUBMISSION
, TRUE
},
629 { US
"suppress_local_fixups", CONTROL_SUPPRESS_LOCAL_FIXUPS
, FALSE
}
632 /* Support data structures for Client SMTP Authorization. acl_verify_csa()
633 caches its result in a tree to avoid repeated DNS queries. The result is an
634 integer code which is used as an index into the following tables of
635 explanatory strings and verification return codes. */
637 static tree_node
*csa_cache
= NULL
;
639 enum { CSA_UNKNOWN
, CSA_OK
, CSA_DEFER_SRV
, CSA_DEFER_ADDR
,
640 CSA_FAIL_EXPLICIT
, CSA_FAIL_DOMAIN
, CSA_FAIL_NOADDR
, CSA_FAIL_MISMATCH
};
642 /* The acl_verify_csa() return code is translated into an acl_verify() return
643 code using the following table. It is OK unless the client is definitely not
644 authorized. This is because CSA is supposed to be optional for sending sites,
645 so recipients should not be too strict about checking it - especially because
646 DNS problems are quite likely to occur. It's possible to use $csa_status in
647 further ACL conditions to distinguish ok, unknown, and defer if required, but
648 the aim is to make the usual configuration simple. */
650 static int csa_return_code
[] = {
652 FAIL
, FAIL
, FAIL
, FAIL
655 static uschar
*csa_status_string
[] = {
656 US
"unknown", US
"ok", US
"defer", US
"defer",
657 US
"fail", US
"fail", US
"fail", US
"fail"
660 static uschar
*csa_reason_string
[] = {
663 US
"deferred (SRV lookup failed)",
664 US
"deferred (target address lookup failed)",
665 US
"failed (explicit authorization required)",
666 US
"failed (host name not authorized)",
667 US
"failed (no authorized addresses)",
668 US
"failed (client address mismatch)"
671 /* Enable recursion between acl_check_internal() and acl_check_condition() */
673 static int acl_check_internal(int, address_item
*, uschar
*, int, uschar
**,
677 /*************************************************
678 * Pick out name from list *
679 *************************************************/
681 /* Use a binary chop method
688 Returns: offset in list, or -1 if not found
692 acl_checkname(uschar
*name
, uschar
**list
, int end
)
698 int mid
= (start
+ end
)/2;
699 int c
= Ustrcmp(name
, list
[mid
]);
700 if (c
== 0) return mid
;
701 if (c
< 0) end
= mid
; else start
= mid
+ 1;
708 /*************************************************
709 * Read and parse one ACL *
710 *************************************************/
712 /* This function is called both from readconf in order to parse the ACLs in the
713 configuration file, and also when an ACL is encountered dynamically (e.g. as
714 the result of an expansion). It is given a function to call in order to
715 retrieve the lines of the ACL. This function handles skipping comments and
716 blank lines (where relevant).
719 func function to get next line of ACL
720 error where to put an error message
722 Returns: pointer to ACL, or NULL
723 NULL can be legal (empty ACL); in this case error will be NULL
727 acl_read(uschar
*(*func
)(void), uschar
**error
)
729 acl_block
*yield
= NULL
;
730 acl_block
**lastp
= &yield
;
731 acl_block
*this = NULL
;
732 acl_condition_block
*cond
;
733 acl_condition_block
**condp
= NULL
;
738 while ((s
= (*func
)()) != NULL
)
741 BOOL negated
= FALSE
;
742 uschar
*saveline
= s
;
745 /* Conditions (but not verbs) are allowed to be negated by an initial
748 while (isspace(*s
)) s
++;
755 /* Read the name of a verb or a condition, or the start of a new ACL, which
756 can be started by a name, or by a macro definition. */
758 s
= readconf_readname(name
, sizeof(name
), s
);
759 if (*s
== ':' || (isupper(name
[0]) && *s
== '=')) return yield
;
761 /* If a verb is unrecognized, it may be another condition or modifier that
762 continues the previous verb. */
764 v
= acl_checkname(name
, verbs
, sizeof(verbs
)/sizeof(char *));
769 *error
= string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name
,
781 *error
= string_sprintf("malformed ACL line \"%s\"", saveline
);
784 this = store_get(sizeof(acl_block
));
786 lastp
= &(this->next
);
789 this->condition
= NULL
;
790 condp
= &(this->condition
);
791 if (*s
== 0) continue; /* No condition on this line */
797 s
= readconf_readname(name
, sizeof(name
), s
); /* Condition name */
800 /* Handle a condition or modifier. */
802 c
= acl_checkname(name
, conditions
, sizeof(conditions
)/sizeof(char *));
805 *error
= string_sprintf("unknown ACL condition/modifier in \"%s\"",
810 /* The modifiers may not be negated */
812 if (negated
&& cond_modifiers
[c
])
814 *error
= string_sprintf("ACL error: negation is not allowed with "
815 "\"%s\"", conditions
[c
]);
819 /* ENDPASS may occur only with ACCEPT or DISCARD. */
821 if (c
== ACLC_ENDPASS
&&
822 this->verb
!= ACL_ACCEPT
&&
823 this->verb
!= ACL_DISCARD
)
825 *error
= string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
826 conditions
[c
], verbs
[this->verb
]);
830 cond
= store_get(sizeof(acl_condition_block
));
833 cond
->u
.negated
= negated
;
836 condp
= &(cond
->next
);
838 /* The "set" modifier is different in that its argument is "name=value"
839 rather than just a value, and we can check the validity of the name, which
840 gives us a variable name to insert into the data block. The original ACL
841 variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
842 extended to 20 of each type, but after that people successfully argued for
843 arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
844 After that, we allow alphanumerics and underscores, but the first character
845 after c or m must be a digit or an underscore. This retains backwards
852 if (Ustrncmp(s
, "acl_c", 5) != 0 &&
853 Ustrncmp(s
, "acl_m", 5) != 0)
855 *error
= string_sprintf("invalid variable name after \"set\" in ACL "
856 "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s
);
861 if (!isdigit(*endptr
) && *endptr
!= '_')
863 *error
= string_sprintf("invalid variable name after \"set\" in ACL "
864 "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
869 while (*endptr
!= 0 && *endptr
!= '=' && !isspace(*endptr
))
871 if (!isalnum(*endptr
) && *endptr
!= '_')
873 *error
= string_sprintf("invalid character \"%c\" in variable name "
874 "in ACL modifier \"set %s\"", *endptr
, s
);
880 cond
->u
.varname
= string_copyn(s
+ 4, endptr
- s
- 4);
882 while (isspace(*s
)) s
++;
885 /* For "set", we are now positioned for the data. For the others, only
886 "endpass" has no data */
888 if (c
!= ACLC_ENDPASS
)
892 *error
= string_sprintf("\"=\" missing after ACL \"%s\" %s", name
,
893 cond_modifiers
[c
]? US
"modifier" : US
"condition");
896 while (isspace(*s
)) s
++;
897 cond
->arg
= string_copy(s
);
906 /*************************************************
907 * Set up added header line(s) *
908 *************************************************/
910 /* This function is called by the add_header modifier, and also from acl_warn()
911 to implement the now-deprecated way of adding header lines using "message" on a
912 "warn" verb. The argument is treated as a sequence of header lines which are
913 added to a chain, provided there isn't an identical one already there.
915 Argument: string of header lines
920 setup_header(uschar
*hstring
)
923 int hlen
= Ustrlen(hstring
);
925 /* An empty string does nothing; otherwise add a final newline if necessary. */
927 if (hlen
<= 0) return;
928 if (hstring
[hlen
-1] != '\n') hstring
= string_sprintf("%s\n", hstring
);
930 /* Loop for multiple header lines, taking care about continuations */
932 for (p
= q
= hstring
; *p
!= 0; )
935 int newtype
= htype_add_bot
;
936 header_line
**hptr
= &acl_added_headers
;
938 /* Find next header line within the string */
942 q
= Ustrchr(q
, '\n');
943 if (*(++q
) != ' ' && *q
!= '\t') break;
946 /* If the line starts with a colon, interpret the instruction for where to
947 add it. This temporarily sets up a new type. */
951 if (strncmpic(p
, US
":after_received:", 16) == 0)
953 newtype
= htype_add_rec
;
956 else if (strncmpic(p
, US
":at_start_rfc:", 14) == 0)
958 newtype
= htype_add_rfc
;
961 else if (strncmpic(p
, US
":at_start:", 10) == 0)
963 newtype
= htype_add_top
;
966 else if (strncmpic(p
, US
":at_end:", 8) == 0)
968 newtype
= htype_add_bot
;
971 while (*p
== ' ' || *p
== '\t') p
++;
974 /* See if this line starts with a header name, and if not, add X-ACL-Warn:
975 to the front of it. */
977 for (s
= p
; s
< q
- 1; s
++)
979 if (*s
== ':' || !isgraph(*s
)) break;
982 s
= string_sprintf("%s%.*s", (*s
== ':')? "" : "X-ACL-Warn: ", q
- p
, p
);
985 /* See if this line has already been added */
987 while (*hptr
!= NULL
)
989 if (Ustrncmp((*hptr
)->text
, s
, hlen
) == 0) break;
990 hptr
= &((*hptr
)->next
);
993 /* Add if not previously present */
997 header_line
*h
= store_get(sizeof(header_line
));
1006 /* Advance for next header line within the string */
1015 /*************************************************
1017 *************************************************/
1019 /* This function is called when a WARN verb's conditions are true. It adds to
1020 the message's headers, and/or writes information to the log. In each case, this
1021 only happens once (per message for headers, per connection for log).
1023 ** NOTE: The header adding action using the "message" setting is historic, and
1024 its use is now deprecated. The new add_header modifier should be used instead.
1027 where ACL_WHERE_xxxx indicating which ACL this is
1028 user_message message for adding to headers
1029 log_message message for logging, if different
1035 acl_warn(int where
, uschar
*user_message
, uschar
*log_message
)
1037 if (log_message
!= NULL
&& log_message
!= user_message
)
1040 string_item
*logged
;
1042 text
= string_sprintf("%s Warning: %s", host_and_ident(TRUE
),
1043 string_printing(log_message
));
1045 /* If a sender verification has failed, and the log message is "sender verify
1046 failed", add the failure message. */
1048 if (sender_verified_failed
!= NULL
&&
1049 sender_verified_failed
->message
!= NULL
&&
1050 strcmpic(log_message
, US
"sender verify failed") == 0)
1051 text
= string_sprintf("%s: %s", text
, sender_verified_failed
->message
);
1053 /* Search previously logged warnings. They are kept in malloc
1054 store so they can be freed at the start of a new message. */
1056 for (logged
= acl_warn_logged
; logged
!= NULL
; logged
= logged
->next
)
1057 if (Ustrcmp(logged
->text
, text
) == 0) break;
1061 int length
= Ustrlen(text
) + 1;
1062 log_write(0, LOG_MAIN
, "%s", text
);
1063 logged
= store_malloc(sizeof(string_item
) + length
);
1064 logged
->text
= (uschar
*)logged
+ sizeof(string_item
);
1065 memcpy(logged
->text
, text
, length
);
1066 logged
->next
= acl_warn_logged
;
1067 acl_warn_logged
= logged
;
1071 /* If there's no user message, we are done. */
1073 if (user_message
== NULL
) return;
1075 /* If this isn't a message ACL, we can't do anything with a user message.
1078 if (where
> ACL_WHERE_NOTSMTP
)
1080 log_write(0, LOG_MAIN
|LOG_PANIC
, "ACL \"warn\" with \"message\" setting "
1081 "found in a non-message (%s) ACL: cannot specify header lines here: "
1082 "message ignored", acl_wherenames
[where
]);
1086 /* The code for setting up header lines is now abstracted into a separate
1087 function so that it can be used for the add_header modifier as well. */
1089 setup_header(user_message
);
1094 /*************************************************
1095 * Verify and check reverse DNS *
1096 *************************************************/
1098 /* Called from acl_verify() below. We look up the host name(s) of the client IP
1099 address if this has not yet been done. The host_name_lookup() function checks
1100 that one of these names resolves to an address list that contains the client IP
1101 address, so we don't actually have to do the check here.
1104 user_msgptr pointer for user message
1105 log_msgptr pointer for log message
1107 Returns: OK verification condition succeeded
1108 FAIL verification failed
1109 DEFER there was a problem verifying
1113 acl_verify_reverse(uschar
**user_msgptr
, uschar
**log_msgptr
)
1117 user_msgptr
= user_msgptr
; /* stop compiler warning */
1119 /* Previous success */
1121 if (sender_host_name
!= NULL
) return OK
;
1123 /* Previous failure */
1125 if (host_lookup_failed
)
1127 *log_msgptr
= string_sprintf("host lookup failed%s", host_lookup_msg
);
1131 /* Need to do a lookup */
1134 debug_printf("looking up host name to force name/address consistency check\n");
1136 if ((rc
= host_name_lookup()) != OK
)
1138 *log_msgptr
= (rc
== DEFER
)?
1139 US
"host lookup deferred for reverse lookup check"
1141 string_sprintf("host lookup failed for reverse lookup check%s",
1143 return rc
; /* DEFER or FAIL */
1146 host_build_sender_fullhost();
1152 /*************************************************
1153 * Check client IP address matches CSA target *
1154 *************************************************/
1156 /* Called from acl_verify_csa() below. This routine scans a section of a DNS
1157 response for address records belonging to the CSA target hostname. The section
1158 is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
1159 If one of the addresses matches the client's IP address, then the client is
1160 authorized by CSA. If there are target IP addresses but none of them match
1161 then the client is using an unauthorized IP address. If there are no target IP
1162 addresses then the client cannot be using an authorized IP address. (This is
1163 an odd configuration - why didn't the SRV record have a weight of 1 instead?)
1166 dnsa the DNS answer block
1167 dnss a DNS scan block for us to use
1168 reset option specifing what portion to scan, as described above
1169 target the target hostname to use for matching RR names
1171 Returns: CSA_OK successfully authorized
1172 CSA_FAIL_MISMATCH addresses found but none matched
1173 CSA_FAIL_NOADDR no target addresses found
1177 acl_verify_csa_address(dns_answer
*dnsa
, dns_scan
*dnss
, int reset
,
1183 BOOL target_found
= FALSE
;
1185 for (rr
= dns_next_rr(dnsa
, dnss
, reset
);
1187 rr
= dns_next_rr(dnsa
, dnss
, RESET_NEXT
))
1189 /* Check this is an address RR for the target hostname. */
1193 && rr
->type
!= T_AAAA
1200 if (strcmpic(target
, rr
->name
) != 0) continue;
1202 target_found
= TRUE
;
1204 /* Turn the target address RR into a list of textual IP addresses and scan
1205 the list. There may be more than one if it is an A6 RR. */
1207 for (da
= dns_address_from_rr(dnsa
, rr
); da
!= NULL
; da
= da
->next
)
1209 /* If the client IP address matches the target IP address, it's good! */
1211 DEBUG(D_acl
) debug_printf("CSA target address is %s\n", da
->address
);
1213 if (strcmpic(sender_host_address
, da
->address
) == 0) return CSA_OK
;
1217 /* If we found some target addresses but none of them matched, the client is
1218 using an unauthorized IP address, otherwise the target has no authorized IP
1221 if (target_found
) return CSA_FAIL_MISMATCH
;
1222 else return CSA_FAIL_NOADDR
;
1227 /*************************************************
1228 * Verify Client SMTP Authorization *
1229 *************************************************/
1231 /* Called from acl_verify() below. This routine calls dns_lookup_special()
1232 to find the CSA SRV record corresponding to the domain argument, or
1233 $sender_helo_name if no argument is provided. It then checks that the
1234 client is authorized, and that its IP address corresponds to the SRV
1235 target's address by calling acl_verify_csa_address() above. The address
1236 should have been returned in the DNS response's ADDITIONAL section, but if
1237 not we perform another DNS lookup to get it.
1240 domain pointer to optional parameter following verify = csa
1242 Returns: CSA_UNKNOWN no valid CSA record found
1243 CSA_OK successfully authorized
1244 CSA_FAIL_* client is definitely not authorized
1245 CSA_DEFER_* there was a DNS problem
1249 acl_verify_csa(uschar
*domain
)
1253 int priority
, weight
, port
;
1260 /* Work out the domain we are using for the CSA lookup. The default is the
1261 client's HELO domain. If the client has not said HELO, use its IP address
1262 instead. If it's a local client (exim -bs), CSA isn't applicable. */
1264 while (isspace(*domain
) && *domain
!= '\0') ++domain
;
1265 if (*domain
== '\0') domain
= sender_helo_name
;
1266 if (domain
== NULL
) domain
= sender_host_address
;
1267 if (sender_host_address
== NULL
) return CSA_UNKNOWN
;
1269 /* If we have an address literal, strip off the framing ready for turning it
1270 into a domain. The framing consists of matched square brackets possibly
1271 containing a keyword and a colon before the actual IP address. */
1273 if (domain
[0] == '[')
1275 uschar
*start
= Ustrchr(domain
, ':');
1276 if (start
== NULL
) start
= domain
;
1277 domain
= string_copyn(start
+ 1, Ustrlen(start
) - 2);
1280 /* Turn domains that look like bare IP addresses into domains in the reverse
1281 DNS. This code also deals with address literals and $sender_host_address. It's
1282 not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
1283 address literals, but it's probably the most friendly thing to do. This is an
1284 extension to CSA, so we allow it to be turned off for proper conformance. */
1286 if (string_is_ip_address(domain
, NULL
) != 0)
1288 if (!dns_csa_use_reverse
) return CSA_UNKNOWN
;
1289 dns_build_reverse(domain
, target
);
1293 /* Find out if we've already done the CSA check for this domain. If we have,
1294 return the same result again. Otherwise build a new cached result structure
1295 for this domain. The name is filled in now, and the value is filled in when
1296 we return from this function. */
1298 t
= tree_search(csa_cache
, domain
);
1299 if (t
!= NULL
) return t
->data
.val
;
1301 t
= store_get_perm(sizeof(tree_node
) + Ustrlen(domain
));
1302 Ustrcpy(t
->name
, domain
);
1303 (void)tree_insertnode(&csa_cache
, t
);
1305 /* Now we are ready to do the actual DNS lookup(s). */
1308 switch (dns_special_lookup(&dnsa
, domain
, T_CSA
, &found
))
1310 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1313 return t
->data
.val
= CSA_DEFER_SRV
;
1315 /* If we found nothing, the client's authorization is unknown. */
1319 return t
->data
.val
= CSA_UNKNOWN
;
1321 /* We got something! Go on to look at the reply in more detail. */
1327 /* Scan the reply for well-formed CSA SRV records. */
1329 for (rr
= dns_next_rr(&dnsa
, &dnss
, RESET_ANSWERS
);
1331 rr
= dns_next_rr(&dnsa
, &dnss
, RESET_NEXT
))
1333 if (rr
->type
!= T_SRV
) continue;
1335 /* Extract the numerical SRV fields (p is incremented) */
1338 GETSHORT(priority
, p
);
1339 GETSHORT(weight
, p
);
1343 debug_printf("CSA priority=%d weight=%d port=%d\n", priority
, weight
, port
);
1345 /* Check the CSA version number */
1347 if (priority
!= 1) continue;
1349 /* If the domain does not have a CSA SRV record of its own (i.e. the domain
1350 found by dns_special_lookup() is a parent of the one we asked for), we check
1351 the subdomain assertions in the port field. At the moment there's only one
1352 assertion: legitimate SMTP clients are all explicitly authorized with CSA
1353 SRV records of their own. */
1355 if (found
!= domain
)
1358 return t
->data
.val
= CSA_FAIL_EXPLICIT
;
1360 return t
->data
.val
= CSA_UNKNOWN
;
1363 /* This CSA SRV record refers directly to our domain, so we check the value
1364 in the weight field to work out the domain's authorization. 0 and 1 are
1365 unauthorized; 3 means the client is authorized but we can't check the IP
1366 address in order to authenticate it, so we treat it as unknown; values
1367 greater than 3 are undefined. */
1369 if (weight
< 2) return t
->data
.val
= CSA_FAIL_DOMAIN
;
1371 if (weight
> 2) continue;
1373 /* Weight == 2, which means the domain is authorized. We must check that the
1374 client's IP address is listed as one of the SRV target addresses. Save the
1375 target hostname then break to scan the additional data for its addresses. */
1377 (void)dn_expand(dnsa
.answer
, dnsa
.answer
+ dnsa
.answerlen
, p
,
1378 (DN_EXPAND_ARG4_TYPE
)target
, sizeof(target
));
1380 DEBUG(D_acl
) debug_printf("CSA target is %s\n", target
);
1385 /* If we didn't break the loop then no appropriate records were found. */
1387 if (rr
== NULL
) return t
->data
.val
= CSA_UNKNOWN
;
1389 /* Do not check addresses if the target is ".", in accordance with RFC 2782.
1390 A target of "." indicates there are no valid addresses, so the client cannot
1391 be authorized. (This is an odd configuration because weight=2 target=. is
1392 equivalent to weight=1, but we check for it in order to keep load off the
1393 root name servers.) Note that dn_expand() turns "." into "". */
1395 if (Ustrcmp(target
, "") == 0) return t
->data
.val
= CSA_FAIL_NOADDR
;
1397 /* Scan the additional section of the CSA SRV reply for addresses belonging
1398 to the target. If the name server didn't return any additional data (e.g.
1399 because it does not fully support SRV records), we need to do another lookup
1400 to obtain the target addresses; otherwise we have a definitive result. */
1402 rc
= acl_verify_csa_address(&dnsa
, &dnss
, RESET_ADDITIONAL
, target
);
1403 if (rc
!= CSA_FAIL_NOADDR
) return t
->data
.val
= rc
;
1405 /* The DNS lookup type corresponds to the IP version used by the client. */
1408 if (Ustrchr(sender_host_address
, ':') != NULL
)
1411 #endif /* HAVE_IPV6 */
1415 #if HAVE_IPV6 && defined(SUPPORT_A6)
1419 switch (dns_lookup(&dnsa
, target
, type
, NULL
))
1421 /* If something bad happened (most commonly DNS_AGAIN), defer. */
1424 return t
->data
.val
= CSA_DEFER_ADDR
;
1426 /* If the query succeeded, scan the addresses and return the result. */
1429 rc
= acl_verify_csa_address(&dnsa
, &dnss
, RESET_ANSWERS
, target
);
1430 if (rc
!= CSA_FAIL_NOADDR
) return t
->data
.val
= rc
;
1431 /* else fall through */
1433 /* If the target has no IP addresses, the client cannot have an authorized
1434 IP address. However, if the target site uses A6 records (not AAAA records)
1435 we have to do yet another lookup in order to check them. */
1440 #if HAVE_IPV6 && defined(SUPPORT_A6)
1441 if (type
== T_AAAA
) { type
= T_A6
; goto DNS_LOOKUP_AGAIN
; }
1444 return t
->data
.val
= CSA_FAIL_NOADDR
;
1450 /*************************************************
1451 * Handle verification (address & other) *
1452 *************************************************/
1454 /* This function implements the "verify" condition. It is called when
1455 encountered in any ACL, because some tests are almost always permitted. Some
1456 just don't make sense, and always fail (for example, an attempt to test a host
1457 lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
1460 where where called from
1461 addr the recipient address that the ACL is handling, or NULL
1462 arg the argument of "verify"
1463 user_msgptr pointer for user message
1464 log_msgptr pointer for log message
1465 basic_errno where to put verify errno
1467 Returns: OK verification condition succeeded
1468 FAIL verification failed
1469 DEFER there was a problem verifying
1474 acl_verify(int where
, address_item
*addr
, uschar
*arg
,
1475 uschar
**user_msgptr
, uschar
**log_msgptr
, int *basic_errno
)
1479 int callout_overall
= -1;
1480 int callout_connect
= -1;
1481 int verify_options
= 0;
1483 BOOL verify_header_sender
= FALSE
;
1484 BOOL defer_ok
= FALSE
;
1485 BOOL callout_defer_ok
= FALSE
;
1486 BOOL no_details
= FALSE
;
1487 BOOL success_on_redirect
= FALSE
;
1488 address_item
*sender_vaddr
= NULL
;
1489 uschar
*verify_sender_address
= NULL
;
1490 uschar
*pm_mailfrom
= NULL
;
1491 uschar
*se_mailfrom
= NULL
;
1493 /* Some of the verify items have slash-separated options; some do not. Diagnose
1494 an error if options are given for items that don't expect them. This code has
1495 now got very message. Refactoring to use a table would be a good idea one day.
1498 uschar
*slash
= Ustrchr(arg
, '/');
1500 uschar
*ss
= string_nextinlist(&list
, &sep
, big_buffer
, big_buffer_size
);
1502 if (ss
== NULL
) goto BAD_VERIFY
;
1504 /* Handle name/address consistency verification in a separate function. */
1506 if (strcmpic(ss
, US
"reverse_host_lookup") == 0)
1508 if (slash
!= NULL
) goto NO_OPTIONS
;
1509 if (sender_host_address
== NULL
) return OK
;
1510 return acl_verify_reverse(user_msgptr
, log_msgptr
);
1513 /* TLS certificate verification is done at STARTTLS time; here we just
1514 test whether it was successful or not. (This is for optional verification; for
1515 mandatory verification, the connection doesn't last this long.) */
1517 if (strcmpic(ss
, US
"certificate") == 0)
1519 if (slash
!= NULL
) goto NO_OPTIONS
;
1520 if (tls_certificate_verified
) return OK
;
1521 *user_msgptr
= US
"no verified certificate";
1525 /* We can test the result of optional HELO verification that might have
1526 occurred earlier. If not, we can attempt the verification now. */
1528 if (strcmpic(ss
, US
"helo") == 0)
1530 if (slash
!= NULL
) goto NO_OPTIONS
;
1531 if (!helo_verified
&& !helo_verify_failed
) smtp_verify_helo();
1532 return helo_verified
? OK
: FAIL
;
1535 /* Do Client SMTP Authorization checks in a separate function, and turn the
1536 result code into user-friendly strings. */
1538 if (strcmpic(ss
, US
"csa") == 0)
1540 rc
= acl_verify_csa(list
);
1541 *log_msgptr
= *user_msgptr
= string_sprintf("client SMTP authorization %s",
1542 csa_reason_string
[rc
]);
1543 csa_status
= csa_status_string
[rc
];
1544 DEBUG(D_acl
) debug_printf("CSA result %s\n", csa_status
);
1545 return csa_return_code
[rc
];
1548 /* Check that all relevant header lines have the correct syntax. If there is
1549 a syntax error, we return details of the error to the sender if configured to
1550 send out full details. (But a "message" setting on the ACL can override, as
1553 if (strcmpic(ss
, US
"header_syntax") == 0)
1555 if (slash
!= NULL
) goto NO_OPTIONS
;
1556 if (where
!= ACL_WHERE_DATA
&& where
!= ACL_WHERE_NOTSMTP
) goto WRONG_ACL
;
1557 rc
= verify_check_headers(log_msgptr
);
1558 if (rc
!= OK
&& smtp_return_error_details
&& *log_msgptr
!= NULL
)
1559 *user_msgptr
= string_sprintf("Rejected after DATA: %s", *log_msgptr
);
1563 /* Check that no recipient of this message is "blind", that is, every envelope
1564 recipient must be mentioned in either To: or Cc:. */
1566 if (strcmpic(ss
, US
"not_blind") == 0)
1568 if (slash
!= NULL
) goto NO_OPTIONS
;
1569 if (where
!= ACL_WHERE_DATA
&& where
!= ACL_WHERE_NOTSMTP
) goto WRONG_ACL
;
1570 rc
= verify_check_notblind();
1573 *log_msgptr
= string_sprintf("bcc recipient detected");
1574 if (smtp_return_error_details
)
1575 *user_msgptr
= string_sprintf("Rejected after DATA: %s", *log_msgptr
);
1580 /* The remaining verification tests check recipient and sender addresses,
1581 either from the envelope or from the header. There are a number of
1582 slash-separated options that are common to all of them. */
1585 /* Check that there is at least one verifiable sender address in the relevant
1586 header lines. This can be followed by callout and defer options, just like
1587 sender and recipient. */
1589 if (strcmpic(ss
, US
"header_sender") == 0)
1591 if (where
!= ACL_WHERE_DATA
&& where
!= ACL_WHERE_NOTSMTP
) goto WRONG_ACL
;
1592 verify_header_sender
= TRUE
;
1595 /* Otherwise, first item in verify argument must be "sender" or "recipient".
1596 In the case of a sender, this can optionally be followed by an address to use
1597 in place of the actual sender (rare special-case requirement). */
1599 else if (strncmpic(ss
, US
"sender", 6) == 0)
1602 if (where
> ACL_WHERE_NOTSMTP
)
1604 *log_msgptr
= string_sprintf("cannot verify sender in ACL for %s "
1605 "(only possible for MAIL, RCPT, PREDATA, or DATA)",
1606 acl_wherenames
[where
]);
1610 verify_sender_address
= sender_address
;
1613 while (isspace(*s
)) s
++;
1614 if (*s
++ != '=') goto BAD_VERIFY
;
1615 while (isspace(*s
)) s
++;
1616 verify_sender_address
= string_copy(s
);
1621 if (strcmpic(ss
, US
"recipient") != 0) goto BAD_VERIFY
;
1624 *log_msgptr
= string_sprintf("cannot verify recipient in ACL for %s "
1625 "(only possible for RCPT)", acl_wherenames
[where
]);
1630 /* Remaining items are optional; they apply to sender and recipient
1631 verification, including "header sender" verification. */
1633 while ((ss
= string_nextinlist(&list
, &sep
, big_buffer
, big_buffer_size
))
1636 if (strcmpic(ss
, US
"defer_ok") == 0) defer_ok
= TRUE
;
1637 else if (strcmpic(ss
, US
"no_details") == 0) no_details
= TRUE
;
1638 else if (strcmpic(ss
, US
"success_on_redirect") == 0) success_on_redirect
= TRUE
;
1640 /* These two old options are left for backwards compatibility */
1642 else if (strcmpic(ss
, US
"callout_defer_ok") == 0)
1644 callout_defer_ok
= TRUE
;
1645 if (callout
== -1) callout
= CALLOUT_TIMEOUT_DEFAULT
;
1648 else if (strcmpic(ss
, US
"check_postmaster") == 0)
1651 if (callout
== -1) callout
= CALLOUT_TIMEOUT_DEFAULT
;
1654 /* The callout option has a number of sub-options, comma separated */
1656 else if (strncmpic(ss
, US
"callout", 7) == 0)
1658 callout
= CALLOUT_TIMEOUT_DEFAULT
;
1662 while (isspace(*ss
)) ss
++;
1668 while (isspace(*ss
)) ss
++;
1670 /* This callout option handling code has become a mess as new options
1671 have been added in an ad hoc manner. It should be tidied up into some
1672 kind of table-driven thing. */
1674 while ((opt
= string_nextinlist(&ss
, &optsep
, buffer
, sizeof(buffer
)))
1677 if (strcmpic(opt
, US
"defer_ok") == 0) callout_defer_ok
= TRUE
;
1678 else if (strcmpic(opt
, US
"no_cache") == 0)
1679 verify_options
|= vopt_callout_no_cache
;
1680 else if (strcmpic(opt
, US
"random") == 0)
1681 verify_options
|= vopt_callout_random
;
1682 else if (strcmpic(opt
, US
"use_sender") == 0)
1683 verify_options
|= vopt_callout_recipsender
;
1684 else if (strcmpic(opt
, US
"use_postmaster") == 0)
1685 verify_options
|= vopt_callout_recippmaster
;
1686 else if (strcmpic(opt
, US
"postmaster") == 0) pm_mailfrom
= US
"";
1687 else if (strcmpic(opt
, US
"fullpostmaster") == 0)
1690 verify_options
|= vopt_callout_fullpm
;
1693 else if (strncmpic(opt
, US
"mailfrom", 8) == 0)
1695 if (!verify_header_sender
)
1697 *log_msgptr
= string_sprintf("\"mailfrom\" is allowed as a "
1698 "callout option only for verify=header_sender (detected in ACL "
1699 "condition \"%s\")", arg
);
1703 while (isspace(*opt
)) opt
++;
1706 *log_msgptr
= string_sprintf("'=' expected after "
1707 "\"mailfrom\" in ACL condition \"%s\"", arg
);
1710 while (isspace(*opt
)) opt
++;
1711 se_mailfrom
= string_copy(opt
);
1714 else if (strncmpic(opt
, US
"postmaster_mailfrom", 19) == 0)
1717 while (isspace(*opt
)) opt
++;
1720 *log_msgptr
= string_sprintf("'=' expected after "
1721 "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg
);
1724 while (isspace(*opt
)) opt
++;
1725 pm_mailfrom
= string_copy(opt
);
1728 else if (strncmpic(opt
, US
"maxwait", 7) == 0)
1731 while (isspace(*opt
)) opt
++;
1734 *log_msgptr
= string_sprintf("'=' expected after \"maxwait\" in "
1735 "ACL condition \"%s\"", arg
);
1738 while (isspace(*opt
)) opt
++;
1739 callout_overall
= readconf_readtime(opt
, 0, FALSE
);
1740 if (callout_overall
< 0)
1742 *log_msgptr
= string_sprintf("bad time value in ACL condition "
1743 "\"verify %s\"", arg
);
1747 else if (strncmpic(opt
, US
"connect", 7) == 0)
1750 while (isspace(*opt
)) opt
++;
1753 *log_msgptr
= string_sprintf("'=' expected after "
1754 "\"callout_overaall\" in ACL condition \"%s\"", arg
);
1757 while (isspace(*opt
)) opt
++;
1758 callout_connect
= readconf_readtime(opt
, 0, FALSE
);
1759 if (callout_connect
< 0)
1761 *log_msgptr
= string_sprintf("bad time value in ACL condition "
1762 "\"verify %s\"", arg
);
1766 else /* Plain time is callout connect/command timeout */
1768 callout
= readconf_readtime(opt
, 0, FALSE
);
1771 *log_msgptr
= string_sprintf("bad time value in ACL condition "
1772 "\"verify %s\"", arg
);
1780 *log_msgptr
= string_sprintf("'=' expected after \"callout\" in "
1781 "ACL condition \"%s\"", arg
);
1787 /* Option not recognized */
1791 *log_msgptr
= string_sprintf("unknown option \"%s\" in ACL "
1792 "condition \"verify %s\"", ss
, arg
);
1797 if ((verify_options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
)) ==
1798 (vopt_callout_recipsender
|vopt_callout_recippmaster
))
1800 *log_msgptr
= US
"only one of use_sender and use_postmaster can be set "
1801 "for a recipient callout";
1805 /* Handle sender-in-header verification. Default the user message to the log
1806 message if giving out verification details. */
1808 if (verify_header_sender
)
1811 rc
= verify_check_header_address(user_msgptr
, log_msgptr
, callout
,
1812 callout_overall
, callout_connect
, se_mailfrom
, pm_mailfrom
, verify_options
,
1816 *basic_errno
= verrno
;
1817 if (smtp_return_error_details
)
1819 if (*user_msgptr
== NULL
&& *log_msgptr
!= NULL
)
1820 *user_msgptr
= string_sprintf("Rejected after DATA: %s", *log_msgptr
);
1821 if (rc
== DEFER
) acl_temp_details
= TRUE
;
1826 /* Handle a sender address. The default is to verify *the* sender address, but
1827 optionally a different address can be given, for special requirements. If the
1828 address is empty, we are dealing with a bounce message that has no sender, so
1829 we cannot do any checking. If the real sender address gets rewritten during
1830 verification (e.g. DNS widening), set the flag to stop it being rewritten again
1831 during message reception.
1833 A list of verified "sender" addresses is kept to try to avoid doing to much
1834 work repetitively when there are multiple recipients in a message and they all
1835 require sender verification. However, when callouts are involved, it gets too
1836 complicated because different recipients may require different callout options.
1837 Therefore, we always do a full sender verify when any kind of callout is
1838 specified. Caching elsewhere, for instance in the DNS resolver and in the
1839 callout handling, should ensure that this is not terribly inefficient. */
1841 else if (verify_sender_address
!= NULL
)
1843 if ((verify_options
& (vopt_callout_recipsender
|vopt_callout_recippmaster
))
1846 *log_msgptr
= US
"use_sender or use_postmaster cannot be used for a "
1847 "sender verify callout";
1851 sender_vaddr
= verify_checked_sender(verify_sender_address
);
1852 if (sender_vaddr
!= NULL
&& /* Previously checked */
1853 callout
<= 0) /* No callout needed this time */
1855 /* If the "routed" flag is set, it means that routing worked before, so
1856 this check can give OK (the saved return code value, if set, belongs to a
1857 callout that was done previously). If the "routed" flag is not set, routing
1858 must have failed, so we use the saved return code. */
1860 if (testflag(sender_vaddr
, af_verify_routed
)) rc
= OK
; else
1862 rc
= sender_vaddr
->special_action
;
1863 *basic_errno
= sender_vaddr
->basic_errno
;
1865 HDEBUG(D_acl
) debug_printf("using cached sender verify result\n");
1868 /* Do a new verification, and cache the result. The cache is used to avoid
1869 verifying the sender multiple times for multiple RCPTs when callouts are not
1870 specified (see comments above).
1872 The cache is also used on failure to give details in response to the first
1873 RCPT that gets bounced for this reason. However, this can be suppressed by
1874 the no_details option, which sets the flag that says "this detail has already
1875 been sent". The cache normally contains just one address, but there may be
1876 more in esoteric circumstances. */
1881 uschar
*save_address_data
= deliver_address_data
;
1883 sender_vaddr
= deliver_make_addr(verify_sender_address
, TRUE
);
1884 if (no_details
) setflag(sender_vaddr
, af_sverify_told
);
1885 if (verify_sender_address
[0] != 0)
1887 /* If this is the real sender address, save the unrewritten version
1888 for use later in receive. Otherwise, set a flag so that rewriting the
1889 sender in verify_address() does not update sender_address. */
1891 if (verify_sender_address
== sender_address
)
1892 sender_address_unrewritten
= sender_address
;
1894 verify_options
|= vopt_fake_sender
;
1896 if (success_on_redirect
)
1897 verify_options
|= vopt_success_on_redirect
;
1899 /* The recipient, qualify, and expn options are never set in
1902 rc
= verify_address(sender_vaddr
, NULL
, verify_options
, callout
,
1903 callout_overall
, callout_connect
, se_mailfrom
, pm_mailfrom
, &routed
);
1905 HDEBUG(D_acl
) debug_printf("----------- end verify ------------\n");
1909 if (Ustrcmp(sender_vaddr
->address
, verify_sender_address
) != 0)
1911 DEBUG(D_acl
) debug_printf("sender %s verified ok as %s\n",
1912 verify_sender_address
, sender_vaddr
->address
);
1916 DEBUG(D_acl
) debug_printf("sender %s verified ok\n",
1917 verify_sender_address
);
1920 else *basic_errno
= sender_vaddr
->basic_errno
;
1922 else rc
= OK
; /* Null sender */
1924 /* Cache the result code */
1926 if (routed
) setflag(sender_vaddr
, af_verify_routed
);
1927 if (callout
> 0) setflag(sender_vaddr
, af_verify_callout
);
1928 sender_vaddr
->special_action
= rc
;
1929 sender_vaddr
->next
= sender_verified_list
;
1930 sender_verified_list
= sender_vaddr
;
1932 /* Restore the recipient address data, which might have been clobbered by
1933 the sender verification. */
1935 deliver_address_data
= save_address_data
;
1938 /* Put the sender address_data value into $sender_address_data */
1940 sender_address_data
= sender_vaddr
->p
.address_data
;
1943 /* A recipient address just gets a straightforward verify; again we must handle
1944 the DEFER overrides. */
1950 if (success_on_redirect
)
1951 verify_options
|= vopt_success_on_redirect
;
1953 /* We must use a copy of the address for verification, because it might
1957 rc
= verify_address(&addr2
, NULL
, verify_options
|vopt_is_recipient
, callout
,
1958 callout_overall
, callout_connect
, se_mailfrom
, pm_mailfrom
, NULL
);
1959 HDEBUG(D_acl
) debug_printf("----------- end verify ------------\n");
1961 *log_msgptr
= addr2
.message
;
1962 *user_msgptr
= (addr2
.user_message
!= NULL
)?
1963 addr2
.user_message
: addr2
.message
;
1964 *basic_errno
= addr2
.basic_errno
;
1966 /* Make $address_data visible */
1967 deliver_address_data
= addr2
.p
.address_data
;
1970 /* We have a result from the relevant test. Handle defer overrides first. */
1972 if (rc
== DEFER
&& (defer_ok
||
1973 (callout_defer_ok
&& *basic_errno
== ERRNO_CALLOUTDEFER
)))
1975 HDEBUG(D_acl
) debug_printf("verify defer overridden by %s\n",
1976 defer_ok
? "defer_ok" : "callout_defer_ok");
1980 /* If we've failed a sender, set up a recipient message, and point
1981 sender_verified_failed to the address item that actually failed. */
1983 if (rc
!= OK
&& verify_sender_address
!= NULL
)
1987 *log_msgptr
= *user_msgptr
= US
"Sender verify failed";
1989 else if (*basic_errno
!= ERRNO_CALLOUTDEFER
)
1991 *log_msgptr
= *user_msgptr
= US
"Could not complete sender verify";
1995 *log_msgptr
= US
"Could not complete sender verify callout";
1996 *user_msgptr
= smtp_return_error_details
? sender_vaddr
->user_message
:
2000 sender_verified_failed
= sender_vaddr
;
2003 /* Verifying an address messes up the values of $domain and $local_part,
2004 so reset them before returning if this is a RCPT ACL. */
2008 deliver_domain
= addr
->domain
;
2009 deliver_localpart
= addr
->local_part
;
2013 /* Syntax errors in the verify argument come here. */
2016 *log_msgptr
= string_sprintf("expected \"sender[=address]\", \"recipient\", "
2017 "\"helo\", \"header_syntax\", \"header_sender\" or "
2018 "\"reverse_host_lookup\" at start of ACL condition "
2019 "\"verify %s\"", arg
);
2022 /* Options supplied when not allowed come here */
2025 *log_msgptr
= string_sprintf("unexpected '/' found in \"%s\" "
2026 "(this verify item has no options)", arg
);
2029 /* Calls in the wrong ACL come here */
2032 *log_msgptr
= string_sprintf("cannot check header contents in ACL for %s "
2033 "(only possible in ACL for DATA)", acl_wherenames
[where
]);
2040 /*************************************************
2041 * Check argument for control= modifier *
2042 *************************************************/
2044 /* Called from acl_check_condition() below
2047 arg the argument string for control=
2048 pptr set to point to the terminating character
2049 where which ACL we are in
2050 log_msgptr for error messages
2052 Returns: CONTROL_xxx value
2056 decode_control(uschar
*arg
, uschar
**pptr
, int where
, uschar
**log_msgptr
)
2061 for (d
= controls_list
;
2062 d
< controls_list
+ sizeof(controls_list
)/sizeof(control_def
);
2065 len
= Ustrlen(d
->name
);
2066 if (Ustrncmp(d
->name
, arg
, len
) == 0) break;
2069 if (d
>= controls_list
+ sizeof(controls_list
)/sizeof(control_def
) ||
2070 (arg
[len
] != 0 && (!d
->has_option
|| arg
[len
] != '/')))
2072 *log_msgptr
= string_sprintf("syntax error in \"control=%s\"", arg
);
2073 return CONTROL_ERROR
;
2082 /*************************************************
2083 * Handle rate limiting *
2084 *************************************************/
2086 /* Called by acl_check_condition() below to calculate the result
2087 of the ACL ratelimit condition.
2089 Note that the return value might be slightly unexpected: if the
2090 sender's rate is above the limit then the result is OK. This is
2091 similar to the dnslists condition, and is so that you can write
2092 ACL clauses like: defer ratelimit = 15 / 1h
2095 arg the option string for ratelimit=
2096 where ACL_WHERE_xxxx indicating which ACL this is
2097 log_msgptr for error messages
2099 Returns: OK - Sender's rate is above limit
2100 FAIL - Sender's rate is below limit
2101 DEFER - Problem opening ratelimit database
2102 ERROR - Syntax error in options.
2106 acl_ratelimit(uschar
*arg
, int where
, uschar
**log_msgptr
)
2108 double limit
, period
;
2111 BOOL have_key
= FALSE
, leaky
= FALSE
, strict
= FALSE
;
2112 BOOL per_byte
= FALSE
, per_cmd
= FALSE
, per_conn
= FALSE
, per_mail
= FALSE
;
2114 tree_node
**anchor
, *t
;
2115 open_db dbblock
, *dbm
;
2116 dbdata_ratelimit
*dbd
;
2119 /* Parse the first two options and record their values in expansion
2120 variables. These variables allow the configuration to have informative
2121 error messages based on rate limits obtained from a table lookup. */
2123 /* First is the maximum number of messages per period and maximum burst
2124 size, which must be greater than or equal to zero. Zero is useful for
2125 rate measurement as opposed to rate limiting. */
2127 sender_rate_limit
= string_nextinlist(&arg
, &sep
, NULL
, 0);
2128 if (sender_rate_limit
== NULL
)
2132 limit
= Ustrtod(sender_rate_limit
, &ss
);
2133 if (tolower(*ss
) == 'k') { limit
*= 1024.0; ss
++; }
2134 else if (tolower(*ss
) == 'm') { limit
*= 1024.0*1024.0; ss
++; }
2135 else if (tolower(*ss
) == 'g') { limit
*= 1024.0*1024.0*1024.0; ss
++; }
2137 if (limit
< 0.0 || *ss
!= 0)
2139 *log_msgptr
= string_sprintf("syntax error in argument for "
2140 "\"ratelimit\" condition: \"%s\" is not a positive number",
2145 /* We use the rest of the argument list following the limit as the
2146 lookup key, because it doesn't make sense to use the same stored data
2147 if the period or options are different. */
2151 /* Second is the rate measurement period and exponential smoothing time
2152 constant. This must be strictly greater than zero, because zero leads to
2153 run-time division errors. */
2155 sender_rate_period
= string_nextinlist(&arg
, &sep
, NULL
, 0);
2156 if (sender_rate_period
== NULL
) period
= -1.0;
2157 else period
= readconf_readtime(sender_rate_period
, 0, FALSE
);
2160 *log_msgptr
= string_sprintf("syntax error in argument for "
2161 "\"ratelimit\" condition: \"%s\" is not a time value",
2162 sender_rate_period
);
2166 /* Parse the other options. Should we check if the per_* options are being
2167 used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */
2169 while ((ss
= string_nextinlist(&arg
, &sep
, big_buffer
, big_buffer_size
))
2172 if (strcmpic(ss
, US
"leaky") == 0) leaky
= TRUE
;
2173 else if (strcmpic(ss
, US
"strict") == 0) strict
= TRUE
;
2174 else if (strcmpic(ss
, US
"per_byte") == 0) per_byte
= TRUE
;
2175 else if (strcmpic(ss
, US
"per_cmd") == 0) per_cmd
= TRUE
;
2176 else if (strcmpic(ss
, US
"per_conn") == 0) per_conn
= TRUE
;
2177 else if (strcmpic(ss
, US
"per_mail") == 0) per_mail
= TRUE
;
2178 else if (strcmpic(ss
, US
"per_rcpt") == 0) per_cmd
= TRUE
; /* alias */
2179 else have_key
= TRUE
;
2181 if (leaky
+ strict
> 1 || per_byte
+ per_cmd
+ per_conn
+ per_mail
> 1)
2183 *log_msgptr
= US
"conflicting options for \"ratelimit\" condition";
2187 /* Default option values */
2188 if (!strict
) leaky
= TRUE
;
2189 if (!per_byte
&& !per_cmd
&& !per_conn
) per_mail
= TRUE
;
2191 /* If there is no explicit key, use the sender_host_address. If there is no
2192 sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */
2194 if (!have_key
&& sender_host_address
!= NULL
)
2195 key
= string_sprintf("%s / %s", key
, sender_host_address
);
2197 HDEBUG(D_acl
) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n",
2198 limit
, period
, key
);
2200 /* See if we have already computed the rate by looking in the relevant tree. For
2201 per-connection rate limiting, store tree nodes and dbdata in the permanent pool
2202 so that they survive across resets. */
2205 old_pool
= store_pool
;
2209 anchor
= &ratelimiters_conn
;
2210 store_pool
= POOL_PERM
;
2212 else if (per_mail
|| per_byte
)
2213 anchor
= &ratelimiters_mail
;
2215 anchor
= &ratelimiters_cmd
;
2217 if (anchor
!= NULL
&& (t
= tree_search(*anchor
, key
)) != NULL
)
2220 /* The following few lines duplicate some of the code below. */
2221 if (dbd
->rate
< limit
) rc
= FAIL
;
2223 store_pool
= old_pool
;
2224 sender_rate
= string_sprintf("%.1f", dbd
->rate
);
2226 debug_printf("ratelimit found pre-computed rate %s\n", sender_rate
);
2230 /* We aren't using a pre-computed rate, so get a previously recorded
2231 rate from the database, update it, and write it back. If there's no
2232 previous rate for this key, create one. */
2234 dbm
= dbfn_open(US
"ratelimit", O_RDWR
, &dbblock
, TRUE
);
2237 store_pool
= old_pool
;
2239 HDEBUG(D_acl
) debug_printf("ratelimit database not available\n");
2240 *log_msgptr
= US
"ratelimit database not available";
2243 dbd
= dbfn_read(dbm
, key
);
2245 gettimeofday(&tv
, NULL
);
2249 HDEBUG(D_acl
) debug_printf("ratelimit initializing new key's data\n");
2250 dbd
= store_get(sizeof(dbdata_ratelimit
));
2251 dbd
->time_stamp
= tv
.tv_sec
;
2252 dbd
->time_usec
= tv
.tv_usec
;
2257 /* The smoothed rate is computed using an exponentially weighted moving
2258 average adjusted for variable sampling intervals. The standard EWMA for
2259 a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
2260 where f() is the measured value and f'() is the smoothed value.
2262 Old data decays out of the smoothed value exponentially, such that data n
2263 samples old is multiplied by a^n. The exponential decay time constant p
2264 is defined such that data p samples old is multiplied by 1/e, which means
2265 that a = exp(-1/p). We can maintain the same time constant for a variable
2266 sampling interval i by using a = exp(-i/p).
2268 The rate we are measuring is messages per period, suitable for directly
2269 comparing with the limit. The average rate between now and the previous
2270 message is period / interval, which we feed into the EWMA as the sample.
2272 It turns out that the number of messages required for the smoothed rate
2273 to reach the limit when they are sent in a burst is equal to the limit.
2274 This can be seen by analysing the value of the smoothed rate after N
2275 messages sent at even intervals. Let k = (1 - a) * p/i
2277 rate_1 = (1 - a) * p/i + a * rate_0
2279 rate_2 = k + a * rate_1
2280 = k + a * k + a^2 * rate_0
2281 rate_3 = k + a * k + a^2 * k + a^3 * rate_0
2282 rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
2283 = rate_0 * a^N + k * (1 - a^N) / (1 - a)
2284 = rate_0 * a^N + p/i * (1 - a^N)
2286 When N is large, a^N -> 0 so rate_N -> p/i as desired.
2288 rate_N = p/i + (rate_0 - p/i) * a^N
2289 a^N = (rate_N - p/i) / (rate_0 - p/i)
2290 N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
2291 N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
2293 Numerical analysis of the above equation, setting the computed rate to
2294 increase from rate_0 = 0 to rate_N = limit, shows that for large sending
2295 rates, p/i, the number of messages N = limit. So limit serves as both the
2296 maximum rate measured in messages per period, and the maximum number of
2297 messages that can be sent in a fast burst. */
2299 double this_time
= (double)tv
.tv_sec
2300 + (double)tv
.tv_usec
/ 1000000.0;
2301 double prev_time
= (double)dbd
->time_stamp
2302 + (double)dbd
->time_usec
/ 1000000.0;
2304 /* We must avoid division by zero, and deal gracefully with the clock going
2305 backwards. If we blunder ahead when time is in reverse then the computed
2306 rate will be bogus. To be safe we clamp interval to a very small number. */
2308 double interval
= this_time
- prev_time
<= 0.0 ? 1e-9
2309 : this_time
- prev_time
;
2311 double i_over_p
= interval
/ period
;
2312 double a
= exp(-i_over_p
);
2314 dbd
->time_stamp
= tv
.tv_sec
;
2315 dbd
->time_usec
= tv
.tv_usec
;
2317 /* If we are measuring the rate in bytes per period, multiply the
2318 measured rate by the message size. If we don't know the message size
2319 then it's safe to just use a value of zero and let the recorded rate
2320 decay as if nothing happened. */
2323 dbd
->rate
= (message_size
< 0 ? 0.0 : (double)message_size
)
2324 * (1 - a
) / i_over_p
+ a
* dbd
->rate
;
2325 else if (per_cmd
&& where
== ACL_WHERE_NOTSMTP
)
2326 dbd
->rate
= (double)recipients_count
2327 * (1 - a
) / i_over_p
+ a
* dbd
->rate
;
2329 dbd
->rate
= (1 - a
) / i_over_p
+ a
* dbd
->rate
;
2332 /* Clients sending at the limit are considered to be over the limit. This
2333 matters for edge cases such the first message sent by a client (which gets
2334 the initial rate of 0.0) when the rate limit is zero (i.e. the client should
2335 be completely blocked). */
2337 if (dbd
->rate
< limit
) rc
= FAIL
;
2340 /* Update the state if the rate is low or if we are being strict. If we
2341 are in leaky mode and the sender's rate is too high, we do not update
2342 the recorded rate in order to avoid an over-aggressive sender's retry
2343 rate preventing them from getting any email through. */
2345 if (rc
== FAIL
|| !leaky
)
2346 dbfn_write(dbm
, key
, dbd
, sizeof(dbdata_ratelimit
));
2349 /* Store the result in the tree for future reference, if necessary. */
2353 t
= store_get(sizeof(tree_node
) + Ustrlen(key
));
2355 Ustrcpy(t
->name
, key
);
2356 (void)tree_insertnode(anchor
, t
);
2359 /* We create the formatted version of the sender's rate very late in
2360 order to ensure that it is done using the correct storage pool. */
2362 store_pool
= old_pool
;
2363 sender_rate
= string_sprintf("%.1f", dbd
->rate
);
2366 debug_printf("ratelimit computed rate %s\n", sender_rate
);
2373 /*************************************************
2374 * Handle conditions/modifiers on an ACL item *
2375 *************************************************/
2377 /* Called from acl_check() below.
2381 cb ACL condition block - if NULL, result is OK
2382 where where called from
2383 addr the address being checked for RCPT, or NULL
2384 level the nesting level
2385 epp pointer to pass back TRUE if "endpass" encountered
2386 (applies only to "accept" and "discard")
2387 user_msgptr user message pointer
2388 log_msgptr log message pointer
2389 basic_errno pointer to where to put verify error
2391 Returns: OK - all conditions are met
2392 DISCARD - an "acl" condition returned DISCARD - only allowed
2393 for "accept" or "discard" verbs
2394 FAIL - at least one condition fails
2395 FAIL_DROP - an "acl" condition returned FAIL_DROP
2396 DEFER - can't tell at the moment (typically, lookup defer,
2397 but can be temporary callout problem)
2398 ERROR - ERROR from nested ACL or expansion failure or other
2403 acl_check_condition(int verb
, acl_condition_block
*cb
, int where
,
2404 address_item
*addr
, int level
, BOOL
*epp
, uschar
**user_msgptr
,
2405 uschar
**log_msgptr
, int *basic_errno
)
2407 uschar
*user_message
= NULL
;
2408 uschar
*log_message
= NULL
;
2411 #ifdef WITH_CONTENT_SCAN
2415 for (; cb
!= NULL
; cb
= cb
->next
)
2420 /* The message and log_message items set up messages to be used in
2421 case of rejection. They are expanded later. */
2423 if (cb
->type
== ACLC_MESSAGE
)
2425 user_message
= cb
->arg
;
2429 if (cb
->type
== ACLC_LOG_MESSAGE
)
2431 log_message
= cb
->arg
;
2435 /* The endpass "condition" just sets a flag to show it occurred. This is
2436 checked at compile time to be on an "accept" or "discard" item. */
2438 if (cb
->type
== ACLC_ENDPASS
)
2444 /* For other conditions and modifiers, the argument is expanded now for some
2445 of them, but not for all, because expansion happens down in some lower level
2446 checking functions in some cases. */
2448 if (cond_expand_at_top
[cb
->type
])
2450 arg
= expand_string(cb
->arg
);
2453 if (expand_string_forcedfail
) continue;
2454 *log_msgptr
= string_sprintf("failed to expand ACL string \"%s\": %s",
2455 cb
->arg
, expand_string_message
);
2456 return search_find_defer
? DEFER
: ERROR
;
2461 /* Show condition, and expanded condition if it's different */
2466 debug_printf("check %s%s %n",
2467 (!cond_modifiers
[cb
->type
] && cb
->u
.negated
)? "!":"",
2468 conditions
[cb
->type
], &lhswidth
);
2470 if (cb
->type
== ACLC_SET
)
2472 debug_printf("acl_%s ", cb
->u
.varname
);
2473 lhswidth
+= 5 + Ustrlen(cb
->u
.varname
);
2476 debug_printf("= %s\n", cb
->arg
);
2479 debug_printf("%.*s= %s\n", lhswidth
,
2483 /* Check that this condition makes sense at this time */
2485 if ((cond_forbids
[cb
->type
] & (1 << where
)) != 0)
2487 *log_msgptr
= string_sprintf("cannot %s %s condition in %s ACL",
2488 cond_modifiers
[cb
->type
]? "use" : "test",
2489 conditions
[cb
->type
], acl_wherenames
[where
]);
2493 /* Run the appropriate test for each condition, or take the appropriate
2494 action for the remaining modifiers. */
2498 case ACLC_ADD_HEADER
:
2502 /* A nested ACL that returns "discard" makes sense only for an "accept" or
2506 rc
= acl_check_internal(where
, addr
, arg
, level
+1, user_msgptr
, log_msgptr
);
2507 if (rc
== DISCARD
&& verb
!= ACL_ACCEPT
&& verb
!= ACL_DISCARD
)
2509 *log_msgptr
= string_sprintf("nested ACL returned \"discard\" for "
2510 "\"%s\" command (only allowed with \"accept\" or \"discard\")",
2516 case ACLC_AUTHENTICATED
:
2517 rc
= (sender_host_authenticated
== NULL
)? FAIL
:
2518 match_isinlist(sender_host_authenticated
, &arg
, 0, NULL
, NULL
, MCL_STRING
,
2522 #ifdef EXPERIMENTAL_BRIGHTMAIL
2523 case ACLC_BMI_OPTIN
:
2525 int old_pool
= store_pool
;
2526 store_pool
= POOL_PERM
;
2527 bmi_current_optin
= string_copy(arg
);
2528 store_pool
= old_pool
;
2533 case ACLC_CONDITION
:
2534 if (Ustrspn(arg
, "0123456789") == Ustrlen(arg
)) /* Digits, or empty */
2535 rc
= (Uatoi(arg
) == 0)? FAIL
: OK
;
2537 rc
= (strcmpic(arg
, US
"no") == 0 ||
2538 strcmpic(arg
, US
"false") == 0)? FAIL
:
2539 (strcmpic(arg
, US
"yes") == 0 ||
2540 strcmpic(arg
, US
"true") == 0)? OK
: DEFER
;
2542 *log_msgptr
= string_sprintf("invalid \"condition\" value \"%s\"", arg
);
2546 control_type
= decode_control(arg
, &p
, where
, log_msgptr
);
2548 /* Check if this control makes sense at this time */
2550 if ((control_forbids
[control_type
] & (1 << where
)) != 0)
2552 *log_msgptr
= string_sprintf("cannot use \"control=%s\" in %s ACL",
2553 controls
[control_type
], acl_wherenames
[where
]);
2557 switch(control_type
)
2559 case CONTROL_AUTH_UNADVERTISED
:
2560 allow_auth_unadvertised
= TRUE
;
2563 #ifdef EXPERIMENTAL_BRIGHTMAIL
2564 case CONTROL_BMI_RUN
:
2569 #ifdef EXPERIMENTAL_DOMAINKEYS
2570 case CONTROL_DK_VERIFY
:
2578 case CONTROL_CASEFUL_LOCAL_PART
:
2579 deliver_localpart
= addr
->cc_local_part
;
2582 case CONTROL_CASELOWER_LOCAL_PART
:
2583 deliver_localpart
= addr
->lc_local_part
;
2586 case CONTROL_ENFORCE_SYNC
:
2587 smtp_enforce_sync
= TRUE
;
2590 case CONTROL_NO_ENFORCE_SYNC
:
2591 smtp_enforce_sync
= FALSE
;
2594 #ifdef WITH_CONTENT_SCAN
2595 case CONTROL_NO_MBOX_UNSPOOL
:
2596 no_mbox_unspool
= TRUE
;
2600 case CONTROL_NO_MULTILINE
:
2601 no_multiline_responses
= TRUE
;
2604 case CONTROL_NO_PIPELINING
:
2605 pipelining_enable
= FALSE
;
2608 case CONTROL_FAKEDEFER
:
2609 case CONTROL_FAKEREJECT
:
2610 fake_response
= (control_type
== CONTROL_FAKEDEFER
) ? DEFER
: FAIL
;
2614 while (*pp
!= 0) pp
++;
2615 fake_response_text
= expand_string(string_copyn(p
+1, pp
-p
-1));
2620 /* Explicitly reset to default string */
2621 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).";
2625 case CONTROL_FREEZE
:
2626 deliver_freeze
= TRUE
;
2627 deliver_frozen_at
= time(NULL
);
2628 freeze_tell
= freeze_tell_config
; /* Reset to configured value */
2629 if (Ustrncmp(p
, "/no_tell", 8) == 0)
2636 *log_msgptr
= string_sprintf("syntax error in \"control=%s\"", arg
);
2641 case CONTROL_QUEUE_ONLY
:
2642 queue_only_policy
= TRUE
;
2645 case CONTROL_SUBMISSION
:
2646 originator_name
= US
"";
2647 submission_mode
= TRUE
;
2650 if (Ustrncmp(p
, "/sender_retain", 14) == 0)
2653 active_local_sender_retain
= TRUE
;
2654 active_local_from_check
= FALSE
;
2656 else if (Ustrncmp(p
, "/domain=", 8) == 0)
2659 while (*pp
!= 0 && *pp
!= '/') pp
++;
2660 submission_domain
= string_copyn(p
+8, pp
-p
-8);
2663 /* The name= option must be last, because it swallows the rest of
2665 else if (Ustrncmp(p
, "/name=", 6) == 0)
2668 while (*pp
!= 0) pp
++;
2669 submission_name
= string_copy(parse_fix_phrase(p
+6, pp
-p
-6,
2670 big_buffer
, big_buffer_size
));
2677 *log_msgptr
= string_sprintf("syntax error in \"control=%s\"", arg
);
2682 case CONTROL_SUPPRESS_LOCAL_FIXUPS
:
2683 suppress_local_fixups
= TRUE
;
2688 #ifdef WITH_CONTENT_SCAN
2690 rc
= mime_decode(&arg
);
2696 int delay
= readconf_readtime(arg
, 0, FALSE
);
2699 *log_msgptr
= string_sprintf("syntax error in argument for \"delay\" "
2700 "modifier: \"%s\" is not a time value", arg
);
2705 HDEBUG(D_acl
) debug_printf("delay modifier requests %d-second delay\n",
2710 debug_printf("delay skipped in -bh checking mode\n");
2713 /* It appears to be impossible to detect that a TCP/IP connection has
2714 gone away without reading from it. This means that we cannot shorten
2715 the delay below if the client goes away, because we cannot discover
2716 that the client has closed its end of the connection. (The connection
2717 is actually in a half-closed state, waiting for the server to close its
2718 end.) It would be nice to be able to detect this state, so that the
2719 Exim process is not held up unnecessarily. However, it seems that we
2720 can't. The poll() function does not do the right thing, and in any case
2721 it is not always available.
2723 NOTE: If ever this state of affairs changes, remember that we may be
2724 dealing with stdin/stdout here, in addition to TCP/IP connections.
2725 Whatever is done must work in both cases. To detected the stdin/stdout
2726 case, check for smtp_in or smtp_out being NULL. */
2730 while (delay
> 0) delay
= sleep(delay
);
2736 #ifdef WITH_OLD_DEMIME
2742 #ifdef EXPERIMENTAL_DOMAINKEYS
2743 case ACLC_DK_DOMAIN_SOURCE
:
2744 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2745 /* check header source of domain against given string */
2746 switch (dk_verify_block
->address_source
) {
2747 case DK_EXIM_ADDRESS_FROM_FROM
:
2748 rc
= match_isinlist(US
"from", &arg
, 0, NULL
,
2749 NULL
, MCL_STRING
, TRUE
, NULL
);
2751 case DK_EXIM_ADDRESS_FROM_SENDER
:
2752 rc
= match_isinlist(US
"sender", &arg
, 0, NULL
,
2753 NULL
, MCL_STRING
, TRUE
, NULL
);
2755 case DK_EXIM_ADDRESS_NONE
:
2756 rc
= match_isinlist(US
"none", &arg
, 0, NULL
,
2757 NULL
, MCL_STRING
, TRUE
, NULL
);
2762 case ACLC_DK_POLICY
:
2763 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2764 /* check policy against given string, default FAIL */
2766 if (dk_verify_block
->signsall
)
2767 rc
= match_isinlist(US
"signsall", &arg
, 0, NULL
,
2768 NULL
, MCL_STRING
, TRUE
, NULL
);
2769 if (dk_verify_block
->testing
)
2770 rc
= match_isinlist(US
"testing", &arg
, 0, NULL
,
2771 NULL
, MCL_STRING
, TRUE
, NULL
);
2774 case ACLC_DK_SENDER_DOMAINS
:
2775 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2776 if (dk_verify_block
->domain
!= NULL
)
2777 rc
= match_isinlist(dk_verify_block
->domain
, &arg
, 0, &domainlist_anchor
,
2778 NULL
, MCL_DOMAIN
, TRUE
, NULL
);
2782 case ACLC_DK_SENDER_LOCAL_PARTS
:
2783 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2784 if (dk_verify_block
->local_part
!= NULL
)
2785 rc
= match_isinlist(dk_verify_block
->local_part
, &arg
, 0, &localpartlist_anchor
,
2786 NULL
, MCL_LOCALPART
, TRUE
, NULL
);
2790 case ACLC_DK_SENDERS
:
2791 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2792 if (dk_verify_block
->address
!= NULL
)
2793 rc
= match_address_list(dk_verify_block
->address
, TRUE
, TRUE
, &arg
, NULL
, -1, 0, NULL
);
2797 case ACLC_DK_STATUS
:
2798 if (dk_verify_block
== NULL
) { rc
= FAIL
; break; };
2799 if (dk_verify_block
->result
> 0) {
2800 switch(dk_verify_block
->result
) {
2801 case DK_EXIM_RESULT_BAD_FORMAT
:
2802 rc
= match_isinlist(US
"bad format", &arg
, 0, NULL
,
2803 NULL
, MCL_STRING
, TRUE
, NULL
);
2805 case DK_EXIM_RESULT_NO_KEY
:
2806 rc
= match_isinlist(US
"no key", &arg
, 0, NULL
,
2807 NULL
, MCL_STRING
, TRUE
, NULL
);
2809 case DK_EXIM_RESULT_NO_SIGNATURE
:
2810 rc
= match_isinlist(US
"no signature", &arg
, 0, NULL
,
2811 NULL
, MCL_STRING
, TRUE
, NULL
);
2813 case DK_EXIM_RESULT_REVOKED
:
2814 rc
= match_isinlist(US
"revoked", &arg
, 0, NULL
,
2815 NULL
, MCL_STRING
, TRUE
, NULL
);
2817 case DK_EXIM_RESULT_NON_PARTICIPANT
:
2818 rc
= match_isinlist(US
"non-participant", &arg
, 0, NULL
,
2819 NULL
, MCL_STRING
, TRUE
, NULL
);
2821 case DK_EXIM_RESULT_GOOD
:
2822 rc
= match_isinlist(US
"good", &arg
, 0, NULL
,
2823 NULL
, MCL_STRING
, TRUE
, NULL
);
2825 case DK_EXIM_RESULT_BAD
:
2826 rc
= match_isinlist(US
"bad", &arg
, 0, NULL
,
2827 NULL
, MCL_STRING
, TRUE
, NULL
);
2835 rc
= verify_check_dnsbl(&arg
);
2839 rc
= match_isinlist(addr
->domain
, &arg
, 0, &domainlist_anchor
,
2840 addr
->domain_cache
, MCL_DOMAIN
, TRUE
, &deliver_domain_data
);
2843 /* The value in tls_cipher is the full cipher name, for example,
2844 TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
2845 cipher names such as DES-CBC3-SHA. But program defensively. We don't know
2846 what may in practice come out of the SSL library - which at the time of
2847 writing is poorly documented. */
2849 case ACLC_ENCRYPTED
:
2850 if (tls_cipher
== NULL
) rc
= FAIL
; else
2852 uschar
*endcipher
= NULL
;
2853 uschar
*cipher
= Ustrchr(tls_cipher
, ':');
2854 if (cipher
== NULL
) cipher
= tls_cipher
; else
2856 endcipher
= Ustrchr(++cipher
, ':');
2857 if (endcipher
!= NULL
) *endcipher
= 0;
2859 rc
= match_isinlist(cipher
, &arg
, 0, NULL
, NULL
, MCL_STRING
, TRUE
, NULL
);
2860 if (endcipher
!= NULL
) *endcipher
= ':';
2864 /* Use verify_check_this_host() instead of verify_check_host() so that
2865 we can pass over &host_data to catch any looked up data. Once it has been
2866 set, it retains its value so that it's still there if another ACL verb
2867 comes through here and uses the cache. However, we must put it into
2868 permanent store in case it is also expected to be used in a subsequent
2869 message in the same SMTP connection. */
2872 rc
= verify_check_this_host(&arg
, sender_host_cache
, NULL
,
2873 (sender_host_address
== NULL
)? US
"" : sender_host_address
, &host_data
);
2874 if (host_data
!= NULL
) host_data
= string_copy_malloc(host_data
);
2877 case ACLC_LOCAL_PARTS
:
2878 rc
= match_isinlist(addr
->cc_local_part
, &arg
, 0,
2879 &localpartlist_anchor
, addr
->localpart_cache
, MCL_LOCALPART
, TRUE
,
2880 &deliver_localpart_data
);
2883 case ACLC_LOG_REJECT_TARGET
:
2889 while ((ss
= string_nextinlist(&s
, &sep
, big_buffer
, big_buffer_size
))
2892 if (Ustrcmp(ss
, "main") == 0) logbits
|= LOG_MAIN
;
2893 else if (Ustrcmp(ss
, "panic") == 0) logbits
|= LOG_PANIC
;
2894 else if (Ustrcmp(ss
, "reject") == 0) logbits
|= LOG_REJECT
;
2897 logbits
|= LOG_MAIN
|LOG_REJECT
;
2898 log_write(0, LOG_MAIN
|LOG_PANIC
, "unknown log name \"%s\" in "
2899 "\"log_reject_target\" in %s ACL", ss
, acl_wherenames
[where
]);
2902 log_reject_target
= logbits
;
2915 if (Ustrncmp(s
, "main", 4) == 0)
2916 { logbits
|= LOG_MAIN
; s
+= 4; }
2917 else if (Ustrncmp(s
, "panic", 5) == 0)
2918 { logbits
|= LOG_PANIC
; s
+= 5; }
2919 else if (Ustrncmp(s
, "reject", 6) == 0)
2920 { logbits
|= LOG_REJECT
; s
+= 6; }
2923 logbits
= LOG_MAIN
|LOG_PANIC
;
2924 s
= string_sprintf(":unknown log name in \"%s\" in "
2925 "\"logwrite\" in %s ACL", arg
, acl_wherenames
[where
]);
2931 while (isspace(*s
)) s
++;
2934 if (logbits
== 0) logbits
= LOG_MAIN
;
2935 log_write(0, logbits
, "%s", string_printing(s
));
2939 #ifdef WITH_CONTENT_SCAN
2942 /* Separate the regular expression and any optional parameters. */
2943 uschar
*ss
= string_nextinlist(&arg
, &sep
, big_buffer
, big_buffer_size
);
2944 /* Run the malware backend. */
2946 /* Modify return code based upon the existance of options. */
2947 while ((ss
= string_nextinlist(&arg
, &sep
, big_buffer
, big_buffer_size
))
2949 if (strcmpic(ss
, US
"defer_ok") == 0 && rc
== DEFER
)
2951 /* FAIL so that the message is passed to the next ACL */
2958 case ACLC_MIME_REGEX
:
2959 rc
= mime_regex(&arg
);
2963 case ACLC_RATELIMIT
:
2964 rc
= acl_ratelimit(arg
, where
, log_msgptr
);
2967 case ACLC_RECIPIENTS
:
2968 rc
= match_address_list(addr
->address
, TRUE
, TRUE
, &arg
, NULL
, -1, 0,
2972 #ifdef WITH_CONTENT_SCAN
2978 case ACLC_SENDER_DOMAINS
:
2981 sdomain
= Ustrrchr(sender_address
, '@');
2982 sdomain
= (sdomain
== NULL
)? US
"" : sdomain
+ 1;
2983 rc
= match_isinlist(sdomain
, &arg
, 0, &domainlist_anchor
,
2984 sender_domain_cache
, MCL_DOMAIN
, TRUE
, NULL
);
2989 rc
= match_address_list(sender_address
, TRUE
, TRUE
, &arg
,
2990 sender_address_cache
, -1, 0, &sender_data
);
2993 /* Connection variables must persist forever */
2997 int old_pool
= store_pool
;
2998 if (cb
->u
.varname
[0] == 'c') store_pool
= POOL_PERM
;
2999 acl_var_create(cb
->u
.varname
)->data
.ptr
= string_copy(arg
);
3000 store_pool
= old_pool
;
3004 #ifdef WITH_CONTENT_SCAN
3007 /* Seperate the regular expression and any optional parameters. */
3008 uschar
*ss
= string_nextinlist(&arg
, &sep
, big_buffer
, big_buffer_size
);
3009 /* Run the spam backend. */
3011 /* Modify return code based upon the existance of options. */
3012 while ((ss
= string_nextinlist(&arg
, &sep
, big_buffer
, big_buffer_size
))
3014 if (strcmpic(ss
, US
"defer_ok") == 0 && rc
== DEFER
)
3016 /* FAIL so that the message is passed to the next ACL */
3024 #ifdef EXPERIMENTAL_SPF
3026 rc
= spf_process(&arg
, sender_address
);
3030 /* If the verb is WARN, discard any user message from verification, because
3031 such messages are SMTP responses, not header additions. The latter come
3032 only from explicit "message" modifiers. However, put the user message into
3033 $acl_verify_message so it can be used in subsequent conditions or modifiers
3034 (until something changes it). */
3037 rc
= acl_verify(where
, addr
, arg
, user_msgptr
, log_msgptr
, basic_errno
);
3038 acl_verify_message
= *user_msgptr
;
3039 if (verb
== ACL_WARN
) *user_msgptr
= NULL
;
3043 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "internal ACL error: unknown "
3044 "condition %d", cb
->type
);
3048 /* If a condition was negated, invert OK/FAIL. */
3050 if (!cond_modifiers
[cb
->type
] && cb
->u
.negated
)
3052 if (rc
== OK
) rc
= FAIL
;
3053 else if (rc
== FAIL
|| rc
== FAIL_DROP
) rc
= OK
;
3056 if (rc
!= OK
) break; /* Conditions loop */
3060 /* If the result is the one for which "message" and/or "log_message" are used,
3061 handle the values of these modifiers. If there isn't a log message set, we make
3062 it the same as the user message.
3064 "message" is a user message that will be included in an SMTP response. Unless
3065 it is empty, it overrides any previously set user message.
3067 "log_message" is a non-user message, and it adds to any existing non-user
3068 message that is already set.
3070 Most verbs have but a single return for which the messages are relevant, but
3071 for "discard", it's useful to have the log message both when it succeeds and
3072 when it fails. For "accept", the message is used in the OK case if there is no
3073 "endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
3076 if (*epp
&& rc
== OK
) user_message
= NULL
;
3078 if (((1<<rc
) & msgcond
[verb
]) != 0)
3081 uschar
*old_user_msgptr
= *user_msgptr
;
3082 uschar
*old_log_msgptr
= (*log_msgptr
!= NULL
)? *log_msgptr
: old_user_msgptr
;
3084 /* If the verb is "warn", messages generated by conditions (verification or
3085 nested ACLs) are always discarded. This also happens for acceptance verbs
3086 when they actually do accept. Only messages specified at this level are used.
3087 However, the value of an existing message is available in $acl_verify_message
3088 during expansions. */
3090 if (verb
== ACL_WARN
||
3091 (rc
== OK
&& (verb
== ACL_ACCEPT
|| verb
== ACL_DISCARD
)))
3092 *log_msgptr
= *user_msgptr
= NULL
;
3094 if (user_message
!= NULL
)
3096 acl_verify_message
= old_user_msgptr
;
3097 expmessage
= expand_string(user_message
);
3098 if (expmessage
== NULL
)
3100 if (!expand_string_forcedfail
)
3101 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand ACL message \"%s\": %s",
3102 user_message
, expand_string_message
);
3104 else if (expmessage
[0] != 0) *user_msgptr
= expmessage
;
3107 if (log_message
!= NULL
)
3109 acl_verify_message
= old_log_msgptr
;
3110 expmessage
= expand_string(log_message
);
3111 if (expmessage
== NULL
)
3113 if (!expand_string_forcedfail
)
3114 log_write(0, LOG_MAIN
|LOG_PANIC
, "failed to expand ACL message \"%s\": %s",
3115 log_message
, expand_string_message
);
3117 else if (expmessage
[0] != 0)
3119 *log_msgptr
= (*log_msgptr
== NULL
)? expmessage
:
3120 string_sprintf("%s: %s", expmessage
, *log_msgptr
);
3124 /* If no log message, default it to the user message */
3126 if (*log_msgptr
== NULL
) *log_msgptr
= *user_msgptr
;
3129 acl_verify_message
= NULL
;
3137 /*************************************************
3138 * Get line from a literal ACL *
3139 *************************************************/
3141 /* This function is passed to acl_read() in order to extract individual lines
3142 of a literal ACL, which we access via static pointers. We can destroy the
3143 contents because this is called only once (the compiled ACL is remembered).
3145 This code is intended to treat the data in the same way as lines in the main
3146 Exim configuration file. That is:
3148 . Leading spaces are ignored.
3150 . A \ at the end of a line is a continuation - trailing spaces after the \
3151 are permitted (this is because I don't believe in making invisible things
3152 significant). Leading spaces on the continued part of a line are ignored.
3154 . Physical lines starting (significantly) with # are totally ignored, and
3155 may appear within a sequence of backslash-continued lines.
3157 . Blank lines are ignored, but will end a sequence of continuations.
3160 Returns: a pointer to the next line
3164 static uschar
*acl_text
; /* Current pointer in the text */
3165 static uschar
*acl_text_end
; /* Points one past the terminating '0' */
3173 /* This loop handles leading blank lines and comments. */
3177 while (isspace(*acl_text
)) acl_text
++; /* Leading spaces/empty lines */
3178 if (*acl_text
== 0) return NULL
; /* No more data */
3179 yield
= acl_text
; /* Potential data line */
3181 while (*acl_text
!= 0 && *acl_text
!= '\n') acl_text
++;
3183 /* If we hit the end before a newline, we have the whole logical line. If
3184 it's a comment, there's no more data to be given. Otherwise, yield it. */
3186 if (*acl_text
== 0) return (*yield
== '#')? NULL
: yield
;
3188 /* After reaching a newline, end this loop if the physical line does not
3189 start with '#'. If it does, it's a comment, and the loop continues. */
3191 if (*yield
!= '#') break;
3194 /* This loop handles continuations. We know we have some real data, ending in
3195 newline. See if there is a continuation marker at the end (ignoring trailing
3196 white space). We know that *yield is not white space, so no need to test for
3197 cont > yield in the backwards scanning loop. */
3202 for (cont
= acl_text
- 1; isspace(*cont
); cont
--);
3204 /* If no continuation follows, we are done. Mark the end of the line and
3213 /* We have encountered a continuation. Skip over whitespace at the start of
3214 the next line, and indeed the whole of the next line or lines if they are
3219 while (*(++acl_text
) == ' ' || *acl_text
== '\t');
3220 if (*acl_text
!= '#') break;
3221 while (*(++acl_text
) != 0 && *acl_text
!= '\n');
3224 /* We have the start of a continuation line. Move all the rest of the data
3225 to join onto the previous line, and then find its end. If the end is not a
3226 newline, we are done. Otherwise loop to look for another continuation. */
3228 memmove(cont
, acl_text
, acl_text_end
- acl_text
);
3229 acl_text_end
-= acl_text
- cont
;
3231 while (*acl_text
!= 0 && *acl_text
!= '\n') acl_text
++;
3232 if (*acl_text
== 0) return yield
;
3235 /* Control does not reach here */
3242 /*************************************************
3243 * Check access using an ACL *
3244 *************************************************/
3246 /* This function is called from address_check. It may recurse via
3247 acl_check_condition() - hence the use of a level to stop looping. The ACL is
3248 passed as a string which is expanded. A forced failure implies no access check
3249 is required. If the result is a single word, it is taken as the name of an ACL
3250 which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
3251 text, complete with newlines, and parsed as such. In both cases, the ACL check
3252 is then run. This function uses an auxiliary function for acl_read() to call
3253 for reading individual lines of a literal ACL. This is acl_getline(), which
3254 appears immediately above.
3257 where where called from
3258 addr address item when called from RCPT; otherwise NULL
3259 s the input string; NULL is the same as an empty ACL => DENY
3260 level the nesting level
3261 user_msgptr where to put a user error (for SMTP response)
3262 log_msgptr where to put a logging message (not for SMTP response)
3264 Returns: OK access is granted
3265 DISCARD access is apparently granted...
3266 FAIL access is denied
3267 FAIL_DROP access is denied; drop the connection
3268 DEFER can't tell at the moment
3273 acl_check_internal(int where
, address_item
*addr
, uschar
*s
, int level
,
3274 uschar
**user_msgptr
, uschar
**log_msgptr
)
3277 acl_block
*acl
= NULL
;
3278 uschar
*acl_name
= US
"inline ACL";
3281 /* Catch configuration loops */
3285 *log_msgptr
= US
"ACL nested too deep: possible loop";
3291 HDEBUG(D_acl
) debug_printf("ACL is NULL: implicit DENY\n");
3295 /* At top level, we expand the incoming string. At lower levels, it has already
3296 been expanded as part of condition processing. */
3300 ss
= expand_string(s
);
3303 if (expand_string_forcedfail
) return OK
;
3304 *log_msgptr
= string_sprintf("failed to expand ACL string \"%s\": %s", s
,
3305 expand_string_message
);
3311 while (isspace(*ss
))ss
++;
3313 /* If we can't find a named ACL, the default is to parse it as an inline one.
3314 (Unless it begins with a slash; non-existent files give rise to an error.) */
3318 /* Handle the case of a string that does not contain any spaces. Look for a
3319 named ACL among those read from the configuration, or a previously read file.
3320 It is possible that the pointer to the ACL is NULL if the configuration
3321 contains a name with no data. If not found, and the text begins with '/',
3322 read an ACL from a file, and save it so it can be re-used. */
3324 if (Ustrchr(ss
, ' ') == NULL
)
3326 tree_node
*t
= tree_search(acl_anchor
, ss
);
3329 acl
= (acl_block
*)(t
->data
.ptr
);
3332 HDEBUG(D_acl
) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss
);
3335 acl_name
= string_sprintf("ACL \"%s\"", ss
);
3336 HDEBUG(D_acl
) debug_printf("using ACL \"%s\"\n", ss
);
3339 else if (*ss
== '/')
3341 struct stat statbuf
;
3342 fd
= Uopen(ss
, O_RDONLY
, 0);
3345 *log_msgptr
= string_sprintf("failed to open ACL file \"%s\": %s", ss
,
3350 if (fstat(fd
, &statbuf
) != 0)
3352 *log_msgptr
= string_sprintf("failed to fstat ACL file \"%s\": %s", ss
,
3357 acl_text
= store_get(statbuf
.st_size
+ 1);
3358 acl_text_end
= acl_text
+ statbuf
.st_size
+ 1;
3360 if (read(fd
, acl_text
, statbuf
.st_size
) != statbuf
.st_size
)
3362 *log_msgptr
= string_sprintf("failed to read ACL file \"%s\": %s",
3363 ss
, strerror(errno
));
3366 acl_text
[statbuf
.st_size
] = 0;
3369 acl_name
= string_sprintf("ACL \"%s\"", ss
);
3370 HDEBUG(D_acl
) debug_printf("read ACL from file %s\n", ss
);
3374 /* Parse an ACL that is still in text form. If it came from a file, remember it
3375 in the ACL tree, having read it into the POOL_PERM store pool so that it
3376 persists between multiple messages. */
3380 int old_pool
= store_pool
;
3381 if (fd
>= 0) store_pool
= POOL_PERM
;
3382 acl
= acl_read(acl_getline
, log_msgptr
);
3383 store_pool
= old_pool
;
3384 if (acl
== NULL
&& *log_msgptr
!= NULL
) return ERROR
;
3387 tree_node
*t
= store_get_perm(sizeof(tree_node
) + Ustrlen(ss
));
3388 Ustrcpy(t
->name
, ss
);
3390 (void)tree_insertnode(&acl_anchor
, t
);
3394 /* Now we have an ACL to use. It's possible it may be NULL. */
3399 int basic_errno
= 0;
3400 BOOL endpass_seen
= FALSE
;
3402 *log_msgptr
= *user_msgptr
= NULL
;
3403 acl_temp_details
= FALSE
;
3405 if (where
== ACL_WHERE_QUIT
&&
3406 acl
->verb
!= ACL_ACCEPT
&&
3407 acl
->verb
!= ACL_WARN
)
3409 *log_msgptr
= string_sprintf("\"%s\" is not allowed in a QUIT ACL",
3414 HDEBUG(D_acl
) debug_printf("processing \"%s\"\n", verbs
[acl
->verb
]);
3416 /* Clear out any search error message from a previous check before testing
3419 search_error_message
= NULL
;
3420 cond
= acl_check_condition(acl
->verb
, acl
->condition
, where
, addr
, level
,
3421 &endpass_seen
, user_msgptr
, log_msgptr
, &basic_errno
);
3423 /* Handle special returns: DEFER causes a return except on a WARN verb;
3424 ERROR always causes a return. */
3429 HDEBUG(D_acl
) debug_printf("%s: condition test deferred\n", verbs
[acl
->verb
]);
3430 if (basic_errno
!= ERRNO_CALLOUTDEFER
)
3432 if (search_error_message
!= NULL
&& *search_error_message
!= 0)
3433 *log_msgptr
= search_error_message
;
3434 if (smtp_return_error_details
) acl_temp_details
= TRUE
;
3438 acl_temp_details
= TRUE
;
3440 if (acl
->verb
!= ACL_WARN
) return DEFER
;
3443 default: /* Paranoia */
3445 HDEBUG(D_acl
) debug_printf("%s: condition test error\n", verbs
[acl
->verb
]);
3449 HDEBUG(D_acl
) debug_printf("%s: condition test succeeded\n",
3454 HDEBUG(D_acl
) debug_printf("%s: condition test failed\n", verbs
[acl
->verb
]);
3457 /* DISCARD and DROP can happen only from a nested ACL condition, and
3458 DISCARD can happen only for an "accept" or "discard" verb. */
3461 HDEBUG(D_acl
) debug_printf("%s: condition test yielded \"discard\"\n",
3466 HDEBUG(D_acl
) debug_printf("%s: condition test yielded \"drop\"\n",
3471 /* At this point, cond for most verbs is either OK or FAIL or (as a result of
3472 a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
3473 for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
3478 if (cond
== OK
|| cond
== DISCARD
) return cond
;
3481 HDEBUG(D_acl
) debug_printf("accept: endpass encountered - denying access\n");
3489 acl_temp_details
= TRUE
;
3495 if (cond
== OK
) return FAIL
;
3499 if (cond
== OK
|| cond
== DISCARD
) return DISCARD
;
3502 HDEBUG(D_acl
) debug_printf("discard: endpass encountered - denying access\n");
3508 if (cond
== OK
) return FAIL_DROP
;
3512 if (cond
!= OK
) return cond
;
3517 acl_warn(where
, *user_msgptr
, *log_msgptr
);
3518 else if (cond
== DEFER
&& (log_extra_selector
& LX_acl_warn_skipped
) != 0)
3519 log_write(0, LOG_MAIN
, "%s Warning: ACL \"warn\" statement skipped: "
3520 "condition test deferred%s%s", host_and_ident(TRUE
),
3521 (*log_msgptr
== NULL
)? US
"" : US
": ",
3522 (*log_msgptr
== NULL
)? US
"" : *log_msgptr
);
3523 *log_msgptr
= *user_msgptr
= NULL
; /* In case implicit DENY follows */
3527 log_write(0, LOG_MAIN
|LOG_PANIC_DIE
, "internal ACL error: unknown verb %d",
3532 /* Pass to the next ACL item */
3537 /* We have reached the end of the ACL. This is an implicit DENY. */
3539 HDEBUG(D_acl
) debug_printf("end of %s: implicit DENY\n", acl_name
);
3544 /*************************************************
3545 * Check access using an ACL *
3546 *************************************************/
3548 /* This is the external interface for ACL checks. It sets up an address and the
3549 expansions for $domain and $local_part when called after RCPT, then calls
3550 acl_check_internal() to do the actual work.
3553 where ACL_WHERE_xxxx indicating where called from
3554 recipient RCPT address for RCPT check, else NULL
3555 s the input string; NULL is the same as an empty ACL => DENY
3556 user_msgptr where to put a user error (for SMTP response)
3557 log_msgptr where to put a logging message (not for SMTP response)
3559 Returns: OK access is granted by an ACCEPT verb
3560 DISCARD access is granted by a DISCARD verb
3561 FAIL access is denied
3562 FAIL_DROP access is denied; drop the connection
3563 DEFER can't tell at the moment
3568 acl_check(int where
, uschar
*recipient
, uschar
*s
, uschar
**user_msgptr
,
3569 uschar
**log_msgptr
)
3573 address_item
*addr
= NULL
;
3575 *user_msgptr
= *log_msgptr
= NULL
;
3576 sender_verified_failed
= NULL
;
3577 ratelimiters_cmd
= NULL
;
3578 log_reject_target
= LOG_MAIN
|LOG_REJECT
;
3580 if (where
== ACL_WHERE_RCPT
)
3582 adb
= address_defaults
;
3584 addr
->address
= recipient
;
3585 if (deliver_split_address(addr
) == DEFER
)
3587 *log_msgptr
= US
"defer in percent_hack_domains check";
3590 deliver_domain
= addr
->domain
;
3591 deliver_localpart
= addr
->local_part
;
3594 rc
= acl_check_internal(where
, addr
, s
, 0, user_msgptr
, log_msgptr
);
3596 deliver_domain
= deliver_localpart
= deliver_address_data
=
3597 sender_address_data
= NULL
;
3599 /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
3600 ACL, which is really in the middle of an SMTP command. */
3604 if (where
> ACL_WHERE_NOTSMTP
|| where
== ACL_WHERE_PREDATA
)
3606 log_write(0, LOG_MAIN
|LOG_PANIC
, "\"discard\" verb not allowed in %s "
3607 "ACL", acl_wherenames
[where
]);
3613 /* A DROP response is not permitted from MAILAUTH */
3615 if (rc
== FAIL_DROP
&& where
== ACL_WHERE_MAILAUTH
)
3617 log_write(0, LOG_MAIN
|LOG_PANIC
, "\"drop\" verb not allowed in %s "
3618 "ACL", acl_wherenames
[where
]);
3622 /* Before giving a response, take a look at the length of any user message, and
3623 split it up into multiple lines if possible. */
3625 if (*user_msgptr
!= NULL
&& Ustrlen(*user_msgptr
) > 75)
3627 uschar
*s
= *user_msgptr
= string_copy(*user_msgptr
);
3633 while (i
< 75 && *ss
!= 0 && *ss
!= '\n') ss
++, i
++;
3634 if (*ss
== 0) break;
3641 while (--t
> s
+ 35)
3645 if (t
[-1] == ':') { tt
= t
; break; }
3646 if (tt
== NULL
) tt
= t
;
3650 if (tt
== NULL
) /* Can't split behind - try ahead */
3655 if (*t
== ' ' || *t
== '\n')
3661 if (tt
== NULL
) break; /* Can't find anywhere to split */
3673 /*************************************************
3674 * Create ACL variable *
3675 *************************************************/
3677 /* Create an ACL variable or reuse an existing one. ACL variables are in a
3678 binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
3681 name pointer to the variable's name, starting with c or m
3683 Returns the pointer to variable's tree node
3687 acl_var_create(uschar
*name
)
3689 tree_node
*node
, **root
;
3690 root
= (name
[0] == 'c')? &acl_var_c
: &acl_var_m
;
3691 node
= tree_search(*root
, name
);
3694 node
= store_get(sizeof(tree_node
) + Ustrlen(name
));
3695 Ustrcpy(node
->name
, name
);
3696 (void)tree_insertnode(root
, node
);
3698 node
->data
.ptr
= NULL
;
3704 /*************************************************
3705 * Write an ACL variable in spool format *
3706 *************************************************/
3708 /* This function is used as a callback for tree_walk when writing variables to
3709 the spool file. To retain spool file compatibility, what is written is -aclc or
3710 -aclm followed by the rest of the name and the data length, space separated,
3711 then the value itself, starting on a new line, and terminated by an additional
3712 newline. When we had only numbered ACL variables, the first line might look
3713 like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
3717 name of the variable
3718 value of the variable
3719 ctx FILE pointer (as a void pointer)
3725 acl_var_write(uschar
*name
, uschar
*value
, void *ctx
)
3727 FILE *f
= (FILE *)ctx
;
3728 fprintf(f
, "-acl%c %s %d\n%s\n", name
[0], name
+1, Ustrlen(value
), value
);
projects / exim.git / blob