Exim went into a mad DNS lookup loop when doing a callout where the
[exim.git] / doc / doc-txt / NewStuff
CommitLineData
d4eb88df 1$Cambridge: exim/doc/doc-txt/NewStuff,v 1.9 2004/11/11 11:40:36 ph10 Exp $
495ae4b0
PH
2
3New Features in Exim
4--------------------
5
6This file contains descriptions of new features that have been added to Exim,
7but have not yet made it into the main manual (which is most conveniently
8updated when there is a relatively large batch of changes). The doc/ChangeLog
9file contains a listing of all changes, including bug fixes.
10
11
35edf2ff
PH
12Version 4.44
13------------
14
15 1. There is a new build-time option called CONFIGURE_GROUP which works like
16 CONFIGURE_OWNER. It specifies one additional group that is permitted for
17 the runtime configuration file when the group write permission is set.
18
69358f02
PH
19 2. The "control=submission" facility has a new option /retain_sender. This
20 has the effect of setting local_sender_retain true and local_from_check
21 false for the incoming message in which it is encountered.
22
5131419f
PH
23 3. $recipients is now available in the predata ACL (oversight).
24
25 4. The value of address_data from a sender verification is now available in
26 $sender_address_data in subsequent conditions in the ACL statement. Note:
27 this is just like $address_data. The value does not persist after the end
28 of the current ACL statement. If you want to preserve it, you can use one
29 of the ACL variables.
30
23c7ff99
PH
31 5. The redirect router has two new options: forbid_sieve_filter and
32 forbid_exim_filter. When filtering is enabled by allow_filter, these
33 options control which type(s) of filtering are permitted. By default, both
34 Exim and Sieve filters are allowed.
35
4deaf07d
PH
36 6. A new option for callouts makes it possible to set a different (usually
37 smaller) timeout for making the SMTP connection. The keyword is "connect".
38 For example:
39
40 verify = sender/callout=5s,connect=1s
41
42 If not specified, it defaults to the general timeout value.
43
2c7db3f5
PH
44 7. The new variables $sender_verify_failure and $recipient_verify_failure
45 contain information about exactly what failed. In an ACL, after one of
46 these failures, the relevant variable contains one of the following words:
47
48 qualify the address was unqualified (no domain), and the message
49 was neither local nor came from an exempted host;
50
51 route routing failed;
52
53 mail routing succeeded, and a callout was attempted; rejection
54 occurred at or before the MAIL command (that is, on initial
55 connection, HELO, or MAIL);
56
57 recipient the RCPT command in a callout was rejected;
58
59 postmaster the postmaster check in a callout was rejected.
60
61 The main use of these variables is expected to be to distinguish between
62 rejections of MAIL and rejections of RCPT.
63
3d235903
PH
64 8. The command line option -dd behaves exactly like -d except when used on a
65 command that starts a daemon process. In that case, debugging is turned off
66 for the subprocesses that the daemon creates. Thus, it is useful for
67 monitoring the behaviour of the daemon without creating as much output as
68 full debugging.
69
d4eb88df
PH
70 9. $host_address is now set to the target address during the checking of
71 ignore_target_hosts.
72
2c7db3f5 73
35edf2ff 74
495ae4b0
PH
75Version 4.43
76------------
77
78 1. There is a new Boolean global option called mua_wrapper, defaulting false.
79 This causes Exim to run an a restricted mode, in order to provide a very
80 specific service.
81
82 Background: On a personal computer, it is a common requirement for all
83 email to be sent to a smarthost. There are plenty of MUAs that can be
84 configured to operate that way, for all the popular operating systems.
85 However, there are MUAs for Unix-like systems that cannot be so configured:
86 they submit messages using the command line interface of
87 /usr/sbin/sendmail. In addition, utility programs such as cron submit
88 messages this way.
89
90 Requirement: The requirement is for something that can provide the
91 /usr/sbin/sendmail interface and deliver messages to a smarthost, but not
92 provide any queueing or retrying facilities. Furthermore, the delivery to
93 the smarthost should be synchronous, so that if it fails, the sending MUA
94 is immediately informed. In other words, we want something that in effect
95 converts a command-line MUA into a TCP/SMTP MUA.
96
97 Solutions: There are a number of applications (for example, ssmtp) that do
98 this job. However, people have found them to be lacking in various ways.
99 For instance, some sites want to allow aliasing and forwarding before
100 sending to the smarthost.
101
102 Using Exim: Exim already had the necessary infrastructure for doing this
103 job. Just a few tweaks were needed to make it behave as required, though it
104 is somewhat of an overkill to use a fully-featured MTA for this purpose.
105
106 Setting mua_wrapper=true causes Exim to run in a special mode where it
107 assumes that it is being used to "wrap" a command-line MUA in the manner
108 just described.
109
110 If you set mua_wrapper=true, you also need to provide a compatible router
111 and transport configuration. Typically there will be just one router and
112 one transport, sending everything to a smarthost.
113
114 When run in MUA wrapping mode, the behaviour of Exim changes in the
115 following ways:
116
117 (a) A daemon cannot be run, nor will Exim accept incoming messages from
118 inetd. In other words, the only way to submit messages is via the
119 command line.
120
121 (b) Each message is synchonously delivered as soon as it is received (-odi
122 is assumed). All queueing options (queue_only, queue_smtp_domains,
123 control=queue, control=freeze in an ACL etc.) are quietly ignored. The
124 Exim reception process does not finish until the delivery attempt is
125 complete. If the delivery was successful, a zero return code is given.
126
127 (c) Address redirection is permitted, but the final routing for all
128 addresses must be to the same remote transport, and to the same list of
129 hosts. Furthermore, the return_address must be the same for all
130 recipients, as must any added or deleted header lines. In other words,
131 it must be possible to deliver the message in a single SMTP
132 transaction, however many recipients there are.
133
134 (d) If the conditions in (c) are not met, or if routing any address results
135 in a failure or defer status, or if Exim is unable to deliver all the
136 recipients successfully to one of the hosts immediately, delivery of
137 the entire message fails.
138
139 (e) Because no queueing is allowed, all failures are treated as permanent;
140 there is no distinction between 4xx and 5xx SMTP response codes from
141 the smarthost. Furthermore, because only a single yes/no response can
142 be given to the caller, it is not possible to deliver to some
143 recipients and not others. If there is an error (temporary or
144 permanent) for any recipient, all are failed.
145
146 (f) If more than one host is listed, Exim will try another host after a
147 connection failure or a timeout, in the normal way. However, if this
148 kind of failure happens for all the hosts, the delivery fails.
149
150 (g) When delivery fails, an error message is written to the standard error
151 stream (as well as to Exim's log), and Exim exits to the caller with a
152 return code value 1. The message is expunged from Exim's spool files.
153 No bounce messages are ever generated.
154
155 (h) No retry data is maintained, and any retry rules are ignored.
156
157 (i) A number of Exim options are overridden: deliver_drop_privilege is
158 forced true, max_rcpt in the smtp transport is forced to "unlimited",
159 remote_max_parallel is forced to one, and fallback hosts are ignored.
160
161 The overall effect is that Exim makes a single synchronous attempt to
162 deliver the message, failing if there is any kind of problem. Because no
163 local deliveries are done and no daemon can be run, Exim does not need root
164 privilege. It should be possible to run it setuid=exim instead of
165 setuid=root. See section 48.3 in the 4.40 manual for a general discussion
166 about the advantages and disadvantages of running without root privilege.
167
168 2. There have been problems with DNS servers when SRV records are looked up.
169 Some mis-behaving servers return a DNS error or timeout when a non-existent
170 SRV record is sought. Similar problems have in the past been reported for
171 MX records. The global dns_again_means_nonexist option can help with this
172 problem, but it is heavy-handed because it is a global option. There are
173 now two new options for the dnslookup router. They are called
174 srv_fail_domains and mx_fail_domains. In each case, the value is a domain
175 list. If an attempt to look up an SRV or MX record results in a DNS failure
176 or "try again" response, and the domain matches the relevant list, Exim
177 behaves as if the DNS had responded "no such record". In the case of an SRV
178 lookup, this means that the router proceeds to look for MX records; in the
179 case of an MX lookup, it proceeds to look for A or AAAA records, unless the
180 domain matches mx_domains.
181
182 3. The following functions are now available in the local_scan() API:
183
184 (a) void header_remove(int occurrence, uschar *name)
185
186 This function removes header lines. If "occurrence" is zero or negative,
187 all occurrences of the header are removed. If occurrence is greater
188 than zero, that particular instance of the header is removed. If no
189 header(s) can be found that match the specification, the function does
190 nothing.
191
192 (b) BOOL header_testname(header_line *hdr, uschar *name, int length,
193 BOOL notdel)
194
195 This function tests whether the given header has the given name. It
196 is not just a string comparison, because whitespace is permitted
197 between the name and the colon. If the "notdel" argument is TRUE, a
198 FALSE return is forced for all "deleted" headers; otherwise they are
199 not treated specially. For example:
200
201 if (header_testname(h, US"X-Spam", 6, TRUE)) ...
202
203 (c) void header_add_at_position(BOOL after, uschar *name, BOOL topnot,
204 int type, char *format, ...)
205
206 This function adds a new header line at a specified point in the header
207 chain. If "name" is NULL, the new header is added at the end of the
208 chain if "after" is TRUE, or at the start if "after" is FALSE. If
209 "name" is not NULL, the headers are searched for the first non-deleted
210 header that matches the name. If one is found, the new header is added
211 before it if "after" is FALSE. If "after" is true, the new header is
212 added after the found header and any adjacent subsequent ones with the
213 same name (even if marked "deleted"). If no matching non-deleted header
214 is found, the "topnot" option controls where the header is added. If it
215 is TRUE, addition is at the top; otherwise at the bottom. Thus, to add
216 a header after all the Received: headers, or at the top if there are no
217 Received: headers, you could use
218
219 header_add_at_position(TRUE, US"Received", TRUE, ' ', "X-xxx: ...");
220
221 Normally, there is always at least one non-deleted Received: header,
222 but there may not be if received_header_text expands to an empty
223 string.
224
225 (d) BOOL receive_remove_recipient(uschar *recipient)
226
227 This is a convenience function to remove a named recipient from the
228 list of recipients. It returns TRUE if a recipient was removed, and
229 FALSE if no matching recipient could be found. The argument must be a
230 complete email address.
231
232 4. When an ACL "warn" statement adds one or more header lines to a message,
233 they are added at the end of the existing header lines by default. It is
234 now possible to specify that any particular header line should be added
235 right at the start (before all the Received: lines) or immediately after
236 the first block of Received: lines in the message. This is done by
237 specifying :at_start: or :after_received: (or, for completeness, :at_end:)
238 before the text of the header line. (Header text cannot start with a colon,
239 as there has to be a header name first.) For example:
240
241 warn message = :after_received:X-My-Header: something or other...
242
243 If more than one header is supplied in a single warn statement, each one is
244 treated independently and can therefore be placed differently. If you add
245 more than one line at the start, or after the Received: block, they will
246 end up in reverse order.
247
248 Warning: This facility currently applies only to header lines that are
249 added in an ACL. It does NOT work for header lines that are added in a
250 system filter or in a router or transport.
251
252 5. There is now a new error code that can be used in retry rules. Its name is
253 "rcpt_4xx", and there are three forms. A literal "rcpt_4xx" matches any 4xx
254 error received for an outgoing SMTP RCPT command; alternatively, either the
255 first or both of the x's can be given as digits, for example: "rcpt_45x" or
256 "rcpt_436". If you want (say) to recognize 452 errors given to RCPT
257 commands by a particular host, and have only a one-hour retry for them, you
258 can set up a retry rule of this form:
259
260 the.host.name rcpt_452 F,1h,10m
261
262 Naturally, this rule must come before any others that would match.
263
264 These new errors apply to both outgoing SMTP (the smtp transport) and
265 outgoing LMTP (either the lmtp transport, or the smtp transport in LMTP
266 mode). Note, however, that they apply only to responses to RCPT commands.
267
268 6. The "postmaster" option of the callout feature of address verification has
269 been extended to make it possible to use a non-empty MAIL FROM address when
270 checking a postmaster address. The new suboption is called "postmaster_
271 mailfrom", and you use it like this:
272
273 require verify = sender/callout=postmaster_mailfrom=abc@x.y.z
274
275 Providing this suboption causes the postmaster check to be done using the
276 given address. The original "postmaster" option is equivalent to
277
278 require verify = sender/callout=postmaster_mailfrom=
279
280 If both suboptions are present, the rightmost one overrides.
281
282 Important notes:
283
284 (1) If you use a non-empty sender address for postmaster checking, there is
285 the likelihood that the remote host will itself initiate a callout
286 check back to your host to check that address. As this is a "normal"
287 callout check, the sender will most probably be empty, thus avoiding
288 possible callout loops. However, to be on the safe side it would be
289 best to set up your own ACLs so that they do not do sender verification
290 checks when the recipient is the address you use for postmaster callout
291 checking.
292
293 (2) The caching arrangements for postmaster checking do NOT take account of
294 the sender address. It is assumed that either the empty address, or a
295 fixed non-empty address will be used. All that Exim remembers is that
296 the postmaster check for the domain succeeded or failed.
297
298 7. When verifying addresses in header lines using the verify=header_sender
299 option, Exim behaves by default as if the addresses are envelope sender
300 addresses from a message. Callout verification therefore tests to see
301 whether a bounce message could be delivered, by using an empty address in
302 the MAIL FROM command. However, it is arguable that these addresses might
303 never be used as envelope senders, and could therefore justifiably reject
304 bounce messages (empty senders). There is now an additional callout option
305 for verify=header_sender that allows you to specify what address to use in
306 the MAIL FROM command. You use it as in this example:
307
308 require verify = header_sender/callout=mailfrom=abcd@x.y.z
309
310 Important notes:
311
312 (1) As in the case of postmaster_mailfrom (see above), you should think
313 about possible loops.
314
315 (2) In this case, as in the case of recipient callouts with non-empty
316 senders (the use_sender option), caching is done on the basis of a
317 recipient/sender pair.
318
319 8. If you build Exim with USE_READLINE=yes in Local/Makefile, it will try to
320 load libreadline dynamically whenever the -be (test expansion) option is
321 used without command line arguments. If successful, it will then use
322 readline() for reading the test data. A line history is supported. By the
323 time Exim does this, it is running as the calling user, so this should not
324 cause any security problems. Security is the reason why this is NOT
325 supported for -bt or -bv, when Exim is running as root or exim,
326 respectively. Note that this option adds to the size of the Exim binary,
327 because the dynamic loading library is not otherwise included. On my
328 desktop it adds about 2.5K. You may need to add -ldl to EXTRA_LIBS when you
329 set USE_READLINE=yes.
330
331 9. Added ${str2b64:<string>} to the expansion operators. This operator
332 converts an arbitrary string into one that is base64 encoded.
333
33410. A new authenticator, called cyrus_sasl, has been added. This requires
335 the presence of the Cyrus SASL library; it authenticates by calling this
336 library, which supports a number of authentication mechanisms, including
337 PLAIN and LOGIN, but also several others that Exim does not support
338 directly. The code for this authenticator was provided by Matthew
339 Byng-Maddick of A L Digital Ltd (http://www.aldigital.co.uk). Here follows
340 draft documentation:
341
342 xx. THE CYRUS_SASL AUTHENTICATOR
343
344 The cyrus_sasl authenticator provides server support for the Cyrus library
345 Implementation of the RFC 2222 "Simple Authentication and Security Layer".
346 It provides a gatewaying mechanism directly to the Cyrus interface, so if
347 your Cyrus library can do, for example, CRAM-MD5, then so can the
348 cyrus_sasl authenticator. By default it uses the public name of the driver
349 to determine which mechanism to support.
350
351 Where access to some kind of secret file is required, for example in GSSAPI
352 or CRAM-MD5, it is worth noting that the authenticator runs as the exim
353 user, and that the Cyrus SASL library has no way of escalating privileges
354 by default. You may also find you need to set environment variables,
355 depending on the driver you are using.
356
357 xx.1 Using cyrus_sasl as a server
358
359 The cyrus_sasl authenticator has four private options. It puts the username
360 (on a successful authentication) into $1.
361
362 server_hostname Type: string* Default: $primary_hostname
363
364 This option selects the hostname that is used when communicating with
365 the library. It is up to the underlying SASL plug-in what it does with
366 this data.
367
368 server_mech Type: string Default: public_name
369
370 This option selects the authentication mechanism this driver should
371 use. It allows you to use a different underlying mechanism from the
372 advertised name. For example:
373
374 sasl:
375 driver = cyrus_sasl
376 public_name = X-ANYTHING
377 server_mech = CRAM-MD5
378 server_set_id = $1
379
380 server_realm Type: string Default: unset
381
382 This is the SASL realm that the server is claiming to be in.
383
384 server_service Type: string Default: "smtp"
385
386 This is the SASL service that the server claims to implement.
387
388 For straigthforward cases, you do not need to set any of the
389 authenticator's private options. All you need to do is to specify an
390 appropriate mechanism as the public name. Thus, if you have a SASL library
391 that supports CRAM-MD5 and PLAIN, you might have two authenticators as
392 follows:
393
394 sasl_cram_md5:
395 driver = cyrus_sasl
396 public_name = CRAM-MD5
397 server_set_id = $1
398
399 sasl_plain:
400 driver = cyrus_sasl
401 public_name = PLAIN
402 server_set_id = $1
403
40411. There is a new global option called tls_on_connect_ports. Its value must be
405 a list of port numbers; the most common use is expected to be
406
407 tls_on_connect_ports = 465
408
409 Setting this option has the same effect as -tls-on-connect on the command
410 line, but only for the specified ports. It applies to all connections, both
411 via the daemon and via inetd. You still need to specify all the ports for
412 the daemon (using daemon_smtp_ports or local_interfaces or the -X command
413 line option) because this option does not add an extra port -- rather, it
414 specifies different behaviour on a port that is defined elsewhere. The
415 -tls-on-connect command line option overrides tls_on_connect_ports, and
416 forces tls-on-connect for all ports.
417
41812. There is a new ACL that is run when a DATA command is received, before the
419 data itself is received. The ACL is defined by acl_smtp_predata. (Compare
420 acl_smtp_data, which is run after the data has been received.)
421 This new ACL allows a negative response to be given to the DATA command
422 itself. Header lines added by MAIL or RCPT ACLs are not visible at this
423 time, but any that are defined here are visible when the acl_smtp_data ACL
424 is run.
425
42613. The "control=submission" ACL modifier has an option "/domain=xxx" which
427 specifies the domain to be used when creating From: or Sender: lines using
428 the authenticated id as a local part. If the option is supplied with an
429 empty domain, that is, just "/domain=", Exim assumes that the authenticated
430 id is a complete email address, and it uses it as is when creating From:
431 or Sender: lines.
432
43314. It is now possible to make retry rules that apply only when the failing
434 message has a specific sender. In particular, this can be used to define
435 retry rules that apply only to bounce messages. The syntax is to add a new
436 third item to a retry rule, of the form "senders=<address list>". The retry
437 timings themselves then become the fourth item. For example:
438
439 * * senders=: F,1h,30m
440
441 would match all bounce messages. If the address list contains white space,
442 it must be enclosed in quotes. For example:
443
444 a.domain timeout senders="x@b.dom : y@c.dom" G,8h,10m,1.5
445
446 When testing retry rules using -brt, you can supply a sender using the -f
447 command line option, like this:
448
449 exim -f "" -brt user@dom.ain
450
451 If you do not set -f with -brt, a retry rule that contains a senders list
452 will never be matched.
453
45415. Two new control modifiers have been added to ACLs: "control = enforce_sync"
455 and "control = no_enforce_sync". This makes it possible to be selective
456 about when SMTP synchronization is enforced. The global option
457 smtp_enforce_sync now specifies the default state of the switch. These
458 controls can appear in any ACL, but the most obvious place to put them is
459 in the ACL defined by acl_smtp_connect, which is run at the start of an
460 incoming SMTP connection, before the first synchronization check.
461
46216. Another two new control modifiers are "control = caseful_local_part" and
463 "control = caselower_local_part". These are permitted only in the ACL
464 specified by acl_smtp_rcpt (i.e. during RCPT processing). By default, the
465 contents of $local_part are lower cased before ACL processing.
466 After "control = caseful_local_part", any uppercase letters in the original
467 local part are restored in $local_part for the rest of the ACL, or until
468 "control = caselower_local_part" is encountered. However, this applies only
469 to local part handling that takes place directly in the ACL (for example,
470 as a key in lookups). If a "verify = recipient" test is obeyed, the
471 case-related handling of the local part during the verification is
472 controlled by the router configuration (see the caseful_local_part generic
473 router option).
474
475 This facility could be used, for example, to add a spam score to local
476 parts containing upper case letters. For example, using $acl_m4 to
477 accumulate the spam score:
478
479 warn control = caseful_local_part
480 set acl_m4 = ${eval:\
481 $acl_m4 + \
482 ${if match{$local_part}{[A-Z]}{1}{0}}\
483 }
484 control = caselower_local_part
485
486 Notice that we put back the lower cased version afterwards, assuming that
487 is what is wanted for subsequent tests.
488
48917. The option hosts_connection_nolog is provided so that certain hosts can be
490 excepted from logging when the +smtp_connection log selector is set. For
491 example, you might want not to log SMTP connections from local processes,
492 or from 127.0.0.1, or from your local LAN. The option is a host list with
493 an unset default. Because it is consulted in the main loop of the daemon,
494 you should strive to restrict its value to a short inline list of IP
495 addresses and networks. To disable logging SMTP connections from local
496 processes, you must create a host list with an empty item. For example:
497
498 hosts_connection_nolog = :
499
500 If the +smtp_connection log selector is not set, this option has no effect.
501
50218. There is now an acl called acl_smtp_quit, which is run for the QUIT
503 command. The outcome of the ACL does not affect the response code to QUIT,
504 which is always 221. Thus, the ACL does not in fact control any access.
505 For this reason, the only verbs that are permitted are "accept" and "warn".
506
507 The ACL can be used for tasks such as custom logging at the end of an SMTP
508 session. For example, you can use ACL variables in other ACLs to count
509 messages, recipients, etc., and log the totals at QUIT time using one or
510 more "logwrite" modifiers on a "warn" command.
511
512 You do not need to have a final "accept", but if you do, you can use a
513 "message" modifier to specify custom text that is sent as part of the 221
514 response.
515
516 This ACL is run only for a "normal" QUIT. For certain kinds of disastrous
517 failure (for example, failure to open a log file, or when Exim is bombing
518 out because it has detected an unrecoverable error), all SMTP commands
519 from the client are given temporary error responses until QUIT is received
520 or the connection is closed. In these special cases, the ACL is not run.
521
52219. The appendfile transport has two new options, mailbox_size and mailbox_
523 filecount. If either these options are set, it is expanded, and the result
524 is taken as the current size of the mailbox or the number of files in the
525 mailbox, respectively. This makes it possible to use some external means of
526 maintaining the data about the size of a mailbox for enforcing quota
527 limits. The result of expanding these option values must be a decimal
528 number, optionally followed by "K" or "M".
529
53020. It seems that there are broken clients in use that cannot handle multiline
531 SMTP responses. Can't people who implement these braindead programs read?
532 RFC 821 mentions multiline responses, and it is over 20 years old. They
533 must handle multiline responses for EHLO, or do they still use HELO?
534 Anyway, here is YAWFAB (yet another workaround for asinine brokenness).
535 There's a new ACL switch that can be set by
536
537 control = no_multiline_responses
538
539 If this is set, it suppresses multiline SMTP responses from ACL rejections.
540 One way of doing this would have been just to put out these responses as
541 one long line. However, RFC 2821 specifies a maximum of 512 bytes per
542 response ("use multiline responses for more" it says), and some of the
543 responses might get close to that. So I have implemented this by doing two
544 very easy things:
545
546 (1) Extra information that is normally output as part of a rejection
547 caused by sender verification failure is omitted. Only the final line
548 (typically "sender verification failed") is now sent.
549
550 (2) If a "message" modifier supplies a multiline response, only the first
551 line is output.
552
553 The setting of the switch can, of course, be made conditional on the
554 calling host.
555
55621. There is now support for the libradius library that comes with FreeBSD.
557 This is an alternative to the radiusclient library that Exim already
558 supports. To use the FreeBSD library, you need to set
559
560 RADIUS_LIB_TYPE=RADLIB
561
562 in Local/Makefile, in addition to RADIUS_CONFIGURE_FILE, and you probably
563 also need -libradius in EXTRALIBS.
564
565
566Version 4.42
567------------
568
569 1. The "personal" filter test is brought up-to-date with recommendations from
570 the Sieve specification: (a) The list of non-personal From: addresses now
571 includes "listserv", "majordomo", and "*-request"; (b) If the message
572 contains any header line starting with "List=-" it is treated as
573 non-personal.
574
575 2. The Sieve functionality has been extended to support the "copy" and
576 "vacation" extensions, and comparison tests.
577
578 3. There is now an overall timeout for performing a callout verification. It
579 defaults to 4 times the callout timeout, which applies to individual SMTP
580 commands during the callout. The overall timeout applies when there is more
581 than one host that can be tried. The timeout is checked before trying the
582 next host. This prevents very long delays if there are a large number of
583 hosts and all are timing out (e.g. when the network connections are timing
584 out). The value of the overall timeout can be changed by specifying an
585 additional sub-option for "callout", called "maxwait". For example:
586
587 verify = sender/callout=5s,maxwait=20s
588
589 4. Changes to the "personal" filter test:
590
591 (1) The list of non-personal local parts in From: addresses has been
592 extended to include "listserv", "majordomo", "*-request", and "owner-*",
593 taken from the Sieve specification recommendations.
594
595 (2) If the message contains any header line starting with "List-" it is
596 treated as non-personal.
597
598 (3) The test for "circular" in the Subject: header line has been removed
599 because it now seems ill-conceived.
600
601 5. The autoreply transport has a new option called never_mail. This is an
602 address list. If any run of the transport creates a message with a
603 recipient that matches any item in the list, that recipient is quietly
604 discarded. If all recipients are discarded, no message is created.
605
606
607Version 4.40
608------------
609
610The documentation is up-to-date for the 4.40 release. What follows here is a
611brief list of the new features that have been added since 4.30.
612
613 1. log_incoming_interface affects more log lines.
614
615 2. New ACL modifier "control = submission".
616
617 3. CONFIGURE_OWNER can be set at build time to define an alternative owner for
618 the configuration file, in addition to root and exim.
619
620 4. Added expansion variables $body_zerocount, $recipient_data, and
621 $sender_data.
622
623 5. The time of last modification of the "new" subdirectory is now used as the
624 "mailbox time last read" when there is a quota error for a maildir
625 delivery.
626
627 6. The special item "+ignore_unknown" may now appear in host lists.
628
629 7. The special domain-matching patterns @mx_any, @mx_primary, and
630 @mx_secondary can now be followed by "/ignore=<ip list>".
631
632 8. New expansion conditions: match_domain, match_address, match_local_part,
633 lt, lti, le, lei, gt, gti, ge, and new expansion operators time_interval,
634 eval10, and base62d.
635
636 9. New lookup type called "iplsearch".
637
63810. New log selectors ident_timeout, tls_certificate_verified, queue_time,
639 deliver_time, outgoing_port, return_path_on_delivery.
640
64111. New global options smtp_active_hostname and tls_require_ciphers.
642
64312. Exinext has -C and -D options.
644
64513. "domainlist_cache" forces caching of an apparently variable list.
646
64714. For compatibility with Sendmail, the command line option -prval:sval
648 is equivalent to -oMr rval -oMs sval.
649
65015. New callout options use_sender and use_postmaster for use when verifying
651 recipients.
652
65316. John Jetmore's "exipick" utility has been added to the distribution.
654
65517. The TLS code now supports CRLs.
656
65718. The dnslookup router and the dnsdb lookup type now support the use of SRV
658 records.
659
66019. The redirect router has a new option called qualify_domain.
661
66220. exigrep's output now also includes lines that are not related to any
663 particular message, but which do match the pattern.
664
66521. New global option write_rejectlog. If it is set false, Exim no longer
666 writes anything to the reject log.
667
668****