1 $Cambridge: exim/doc/doc-txt/NewStuff,v 1.66 2005/09/06 13:17:36 ph10 Exp $
6 This file contains descriptions of new features that have been added to Exim,
7 but have not yet made it into the main manual (which is most conveniently
8 updated when there is a relatively large batch of changes). The doc/ChangeLog
9 file contains a listing of all changes, including bug fixes.
14 TK/01 Added the "success_on_redirect" address verification option. When an
15 address generates new addresses during routing, Exim will abort
16 verification with "success" when more than one address has been
17 generated, but continue to verify a single new address. The latter
18 does not happen when the new "success_on_redirect" option is set, like
20 require verify = recipient/success_on_redirect/callout=10s
22 In that case, verification will succeed when a router generates a new
25 PH/01 Support for SQLite database lookups has been added. This is another
26 query-style lookup, but it is slightly different from the others because
27 a file name is required in addition to the SQL query. This is because an
28 SQLite database is a single file and there is no daemon as in other SQL
29 databases. The interface to Exim requires the name of the file, as an
30 absolute path, to be given at the start of the query. It is separated
31 from the query by white space. This means that the path name cannot
32 contain white space. Here is a lookup expansion example:
34 ${lookup sqlite {/some/thing/sqlitedb \
35 select name from aliases where id='ph10';}}
37 In a list, the syntax is similar. For example:
39 domainlist relay_domains = sqlite;/some/thing/sqlitedb \
40 select * from relays where ip='$sender_host_address';
42 The only character affected by the ${quote_sqlite: operator is a single
43 quote, which it doubles.
45 The SQLite library handles multiple simultaneous accesses to the database
46 internally. Multiple readers are permitted, but only one process can
47 update at once. Attempts to access the database while it is being updated
48 are rejected after a timeout period, during which the SQLite library
49 waits for the lock to be released. In Exim, the default timeout is set
50 to 5 seconds, but it can be changed by means of the sqlite_lock_timeout
53 Note that you must set LOOKUP_SQLITE=yes in Local/Makefile in order to
54 obtain SQLite support, and you will also need to add -lsqlite3 to the
55 EXTRALIBS setting. And of course, you have to install SQLite on your
58 PH/02 The variable $message_id is now deprecated, to be replaced by
59 $message_exim_id, which makes it clearer which ID is being referenced.
61 PH/03 The use of forbid_filter_existstest now also locks out the use of the
62 ${stat: expansion item.
64 PH/04 The IGNOREQUOTA extension to the LMTP protocol is now available in both
65 the lmtp transport and the smtp transport running in LMTP mode. In the
66 lmtp transport there is a new Boolean option called ignore_quota, and in
67 the smtp transport there is a new Boolean option called
68 lmtp_ignore_quota. If either of these options is set TRUE, the string
69 "IGNOREQUOTA" is added to RCPT commands when using the LMTP protocol,
70 provided that the server has advertised support for IGNOREQUOTA in its
71 response to the LHLO command.
73 PH/05 Previously, if "verify = helo" was set in an ACL, the condition was true
74 only if the host matched helo_try_verify_hosts, which caused the
75 verification to occur when the EHLO/HELO command was issued. The ACL just
76 tested the remembered result. Now, if a previous verification attempt has
77 not happened, "verify = helo" does it there and then.
79 PH/06 It is now possible to specify a port number along with a host name or
80 IP address in the list of hosts defined in the manualroute or
81 queryprogram routers, fallback_hosts, or the "hosts" option of the smtp
82 transport. These all override any port specification on the transport.
83 The relatively standard syntax of using a colon separator has been
84 adopted, but there are some gotchas that need attention:
86 * In all these lists of hosts, colon is the default separator, so either
87 the colon that specifies a port must be doubled, or the separator must
88 be changed. The following two examples have the same effect:
90 fallback_hosts = host1.tld::1225 : host2.tld::1226
91 fallback_hosts = <; host1.tld:1225 ; host2.tld:1226
93 * When IPv6 addresses are involved, it gets worse, because they contain
94 colons of their own. To make this case easier, it is permitted to
95 enclose an IP address (either v4 or v6) in square brackets if a port
96 number follows. Here's an example from a manualroute router:
98 route_list = * "</ [10.1.1.1]:1225 / [::1]:1226"
100 If the "/MX" feature is to be used as well as a port specifier, the port
101 must come last. For example:
103 route_list = * dom1.tld/mx::1225
105 PH/07 $smtp_command_argument is now set for all SMTP commands, not just the
106 non-message ones. This makes it possible to inspect the complete command
107 for RCPT commands, for example.
109 PH/08 The ${eval expansion now supports % as a "remainder" operator.
111 PH/09 There is a new ACL condition "verify = not_blind". It checks that there
112 are no blind (bcc) recipients in the message. Every envelope recipient
113 must appear either in a To: header line or in a Cc: header line for this
114 condition to be true. Local parts are checked case-sensitively; domains
115 are checked case-insensitively. If Resent-To: or Resent-Cc: header lines
116 exist, they are also checked. This condition can be used only in a DATA
119 There are, of course, many legitimate messages that make use of blind
120 (bcc) recipients. This check should not be used on its own for blocking
127 TF/01 Support for checking Client SMTP Authorization has been added. CSA is a
128 system which allows a site to advertise which machines are and are not
129 permitted to send email. This is done by placing special SRV records in
130 the DNS, which are looked up using the client's HELO domain. At this
131 time CSA is still an Internet-Draft.
133 Client SMTP Authorization checks are performed by the ACL condition
134 verify=csa. This will fail if the client is not authorized. If there is
135 a DNS problem, or if no valid CSA SRV record is found, or if the client
136 is authorized, the condition succeeds. These three cases can be
137 distinguished using the expansion variable $csa_status, which can take
138 one of the values "fail", "defer", "unknown", or "ok". The condition
139 does not itself defer because that would be likely to cause problems
140 for legitimate email.
142 The error messages produced by the CSA code include slightly more
143 detail. If $csa_status is "defer" this may be because of problems
144 looking up the CSA SRV record, or problems looking up the CSA target
145 address record. There are four reasons for $csa_status being "fail":
146 the client's host name is explicitly not authorized; the client's IP
147 address does not match any of the CSA target IP addresses; the client's
148 host name is authorized but it has no valid target IP addresses (e.g.
149 the target's addresses are IPv6 and the client is using IPv4); or the
150 client's host name has no CSA SRV record but a parent domain has
151 asserted that all subdomains must be explicitly authorized.
153 The verify=csa condition can take an argument which is the domain to
154 use for the DNS query. The default is verify=csa/$sender_helo_name.
156 This implementation includes an extension to CSA. If the query domain
157 is an address literal such as [192.0.2.95], or if it is a bare IP
158 address, Exim will search for CSA SRV records in the reverse DNS as if
159 the HELO domain was e.g. 95.2.0.192.in-addr.arpa. Therefore it is
160 meaningful to say, for example, verify=csa/$sender_host_address - in
161 fact, this is the check that Exim performs if the client does not say
162 HELO. This extension can be turned off by setting the main
163 configuration option dns_csa_use_reverse = false.
165 If a CSA SRV record is not found for the domain itself, then a search
166 is performed through its parent domains for a record which might be
167 making assertions about subdomains. The maximum depth of this search is
168 limited using the main configuration option dns_csa_search_limit, which
169 takes the value 5 by default. Exim does not look for CSA SRV records in
170 a top level domain, so the default settings handle HELO domains as long
171 as seven (hostname.five.four.three.two.one.com) which encompasses the
172 vast majority of legitimate HELO domains.
174 The dnsdb lookup also has support for CSA. Although dnsdb already
175 supports SRV lookups, this is not sufficient because of the extra
176 parent domain search behaviour of CSA, and (as with PTR lookups)
177 dnsdb also turns IP addresses into lookups in the reverse DNS space.
178 The result of ${lookup dnsdb {csa=$sender_helo_name} } has two
179 space-separated fields: an authorization code and a target host name.
180 The authorization code can be "Y" for yes, "N" for no, "X" for explicit
181 authorization required but absent, or "?" for unknown.
183 PH/01 The amount of output produced by the "make" process has been reduced,
184 because the compile lines are often rather long, making it all pretty
185 unreadable. The new style is along the lines of the 2.6 Linux kernel:
186 just a short line for each module that is being compiled or linked.
187 However, it is still possible to get the full output, by calling "make"
192 The value of FULLECHO defaults to "@", the flag character that suppresses
193 command reflection in "make". When you ask for the full output, it is
194 given in addition to the the short output.
196 TF/02 There have been two changes concerned with submission mode:
198 Until now submission mode always left the return path alone, whereas
199 locally-submitted messages from untrusted users have the return path
200 fixed to the user's email address. Submission mode now fixes the return
201 path to the same address as is used to create the Sender: header. If
202 /sender_retain is specified then both the Sender: header and the return
205 Note that the changes caused by submission mode take effect after the
206 predata ACL. This means that any sender checks performed before the
207 fix-ups will use the untrusted sender address specified by the user, not
208 the trusted sender address specified by submission mode. Although this
209 might be slightly unexpected, it does mean that you can configure ACL
210 checks to spot that a user is trying to spoof another's address, for
213 There is also a new /name= option for submission mode which allows you
214 to specify the user's full name to be included in the Sender: header.
217 accept authenticated = *
218 control = submission/name=${lookup {$authenticated_id} \
219 lsearch {/etc/exim/namelist} }
221 The namelist file contains entries like
225 And the resulting Sender: header looks like
227 Sender: Tony Finch <fanf@exim.org>
229 TF/03 The control = fakereject ACL modifier now has a fakedefer counterpart,
230 which works in exactly the same way except it causes a fake SMTP 450
231 response after the message data instead of a fake SMTP 550 response.
232 You must take care when using fakedefer because it will cause messages
233 to be duplicated when the sender retries. Therefore you should not use
234 fakedefer if the message will be delivered normally.
236 TF/04 There is a new ratelimit ACL condition which can be used to measure
237 and control the rate at which clients can send email. This is more
238 powerful than the existing smtp_ratelimit_* options, because those
239 options only control the rate of commands in a single SMTP session,
240 whereas the new ratelimit condition works across all connections
241 (concurrent and sequential) to the same host.
243 The syntax of the ratelimit condition is:
245 ratelimit = <m> / <p> / <options> / <key>
247 If the average client sending rate is less than m messages per time
248 period p then the condition is false, otherwise it is true.
250 The parameter p is the smoothing time constant, in the form of an Exim
251 time interval e.g. 8h for eight hours. A larger time constant means it
252 takes Exim longer to forget a client's past behaviour. The parameter m is
253 the maximum number of messages that a client can send in a fast burst. By
254 increasing both m and p but keeping m/p constant, you can allow a client
255 to send more messages in a burst without changing its overall sending
256 rate limit. Conversely, if m and p are both small then messages must be
257 sent at an even rate.
259 The key is used to look up the data used to calcluate the client's
260 average sending rate. This data is stored in a database maintained by
261 Exim in its spool directory alongside the retry database etc. For
262 example, you can limit the sending rate of each authenticated user,
263 independent of the computer they are sending from, by setting the key
264 to $authenticated_id. The default key is $sender_host_address.
265 Internally, Exim includes the smoothing constant p and the options in
266 the lookup key because they alter the meaning of the stored data.
267 This is not true for the limit m, so you can alter the configured
268 maximum rate and Exim will still remember clients' past behaviour,
269 but if you alter the other ratelimit parameters Exim will effectively
270 forget their past behaviour.
272 Each ratelimit condition can have up to two options. The first option
273 specifies what Exim measures the rate of, and the second specifies how
274 Exim handles excessively fast clients.
276 The per_mail option means that it measures the client's rate of sending
277 messages. This is the default if none of the per_* options is specified.
279 The per_conn option means that it measures the client's connection rate.
281 The per_byte option limits the sender's email bandwidth. Note that it
282 is best to use this option in the DATA ACL; if it is used in an earlier
283 ACL it relies on the SIZE parameter on the MAIL command, which may be
284 inaccurate or completely missing. You can follow the limit m in the
285 configuration with K, M, or G to specify limits in kilobytes,
286 megabytes, or gigabytes respectively.
288 The per_cmd option means that Exim recomputes the rate every time the
289 condition is processed, which can be used to limit the SMTP command rate.
290 The alias per_rcpt is provided for use in the RCPT ACL instead of per_cmd
291 to make it clear that the effect is to limit the rate at which recipients
292 are accepted. Note that in this case the rate limiting engine will see a
293 message with many recipients as a large high-speed burst.
295 If a client's average rate is greater than the maximum, the rate
296 limiting engine can react in two possible ways, depending on the
297 presence of the strict or leaky options. This is independent of the
298 other counter-measures (e.g. rejecting the message) that may be
299 specified by the rest of the ACL. The default mode is leaky, which
300 avoids a sender's over-aggressive retry rate preventing it from getting
303 The strict option means that the client's recorded rate is always
304 updated. The effect of this is that Exim measures the client's average
305 rate of attempts to send email, which can be much higher than the
306 maximum. If the client is over the limit it will be subjected to
307 counter-measures until it slows down below the maximum rate.
309 The leaky option means that the client's recorded rate is not updated
310 if it is above the limit. The effect of this is that Exim measures the
311 client's average rate of successfully sent email, which cannot be
312 greater than the maximum. If the client is over the limit it will
313 suffer some counter-measures, but it will still be able to send email
314 at the configured maximum rate, whatever the rate of its attempts.
316 As a side-effect, the ratelimit condition will set the expansion
317 variables $sender_rate containing the client's computed rate,
318 $sender_rate_limit containing the configured value of m, and
319 $sender_rate_period containing the configured value of p.
321 Exim's other ACL facilities are used to define what counter-measures
322 are taken when the rate limit is exceeded. This might be anything from
323 logging a warning (e.g. while measuring existing sending rates in order
324 to define our policy), through time delays to slow down fast senders,
325 up to rejecting the message. For example,
327 # Log all senders' rates
329 ratelimit = 0 / 1h / strict
331 Sender rate $sender_rate > $sender_rate_limit / $sender_rate_period
333 # Slow down fast senders
335 ratelimit = 100 / 1h / per_rcpt / strict
336 delay = ${eval: 10 * ($sender_rate - $sender_rate_limit) }
338 # Keep authenticated users under control
340 ratelimit = 100 / 1d / strict / $authenticated_id
342 # System-wide rate limit
344 message = Sorry, too busy. Try again later.
345 ratelimit = 10 / 1s / $primary_hostname
347 # Restrict incoming rate from each host, with a default rate limit
348 # set using a macro and special cases looked up in a table.
350 message = Sender rate $sender_rate exceeds \
351 $sender_rate_limit messages per $sender_rate_period
352 ratelimit = ${lookup {$sender_host_address} \
353 cdb {DB/ratelimits.cdb} \
354 {$value} {RATELIMIT} }
356 Warning: if you have a busy server with a lot of ratelimit tests,
357 especially with the per_rcpt option, you may suffer from a performance
358 bottleneck caused by locking on the ratelimit hints database. Apart from
359 making your ACLs less complicated, you can reduce the problem by using a
360 RAM disk for Exim's hints directory, /var/spool/exim/db/. However this
361 means that Exim will lose its hints data after a reboot (including retry
362 hints, the callout cache, and ratelimit data).
364 TK/01 Added an 'spf' lookup type that will return an SPF result for a given
365 email address (the key) and an IP address (the database):
367 ${lookup {tom@duncanthrax.net} spf{217.115.139.137}}
369 The lookup will return the same result strings as they can appear in
370 $spf_result (pass,fail,softfail,neutral,none,err_perm,err_temp). The
371 lookup is armored in EXPERIMENTAL_SPF. Currently, only IPv4 addresses
374 Patch submitted by Chris Webb <chris@arachsys.com>.
376 PH/02 There's a new verify callout option, "fullpostmaster", which first acts
377 as "postmaster" and checks the recipient <postmaster@domain>. If that
378 fails, it tries just <postmaster>, without a domain, in accordance with
379 the specification in RFC 2821.
381 PH/03 The action of the auto_thaw option has been changed. It no longer applies
382 to frozen bounce messages.
384 TK/02 There are two new expansion items to help with the implementation of
385 the BATV "prvs" scheme in an Exim configuration:
388 ${prvs {<ADDRESS>}{<KEY>}{[KEYNUM]}}
390 The "prvs" expansion item takes three arguments: A qualified RFC2821
391 email address, a key and an (optional) key number. All arguments are
392 expanded before being used, so it is easily possible to lookup a key
393 and key number using the address as the lookup key. The key number is
394 optional and defaults to "0". The item will expand to a "prvs"-signed
395 email address, to be typically used with the "return_path" option on
396 a smtp transport. The decision if BATV should be used with a given
397 sender/recipient pair should be done on router level, to avoid having
398 to set "max_rcpt = 1" on the transport.
401 ${prvscheck {<ADDRESS>}{<SECRET>}{<RETURN_STRING>}}
403 The "prvscheck" expansion item takes three arguments. Argument 1 is
404 expanded first. When the expansion does not yield a SYNTACTICALLY
405 valid "prvs"-scheme address, the whole "prvscheck" item expands to
406 the empty string. If <ADDRESS> is a "prvs"-encoded address after
407 expansion, two expansion variables are set up:
409 $prvscheck_address Contains the "prvs"-decoded version of
410 the address from argument 1.
412 $prvscheck_keynum Contains the key number extracted from
413 the "prvs"-address in argument 1.
415 These two variables can be used in the expansion code of argument 2
416 to retrieve the <SECRET>. The VALIDITY of the "prvs"-signed address
417 is then checked. The result is stored in yet another expansion
420 $prvscheck_result Contains the result of a "prvscheck"
421 expansion: Unset (the empty string) for
422 failure, "1" for success.
424 The "prvscheck" expansion expands to the empty string if <ADDRESS>
425 is not a SYNTACTICALLY valid "prvs"-scheme address. Otherwise,
426 argument 3 defines what "prvscheck" expands to: If argument 3
427 is the empty string, "prvscheck" expands to the decoded version
428 of the address (no matter if it is CRYPTOGRAPHICALLY valid or not).
429 If argument 3 expands to a non-empty string, "prvscheck" expands
438 PRVSCHECK_SQL = ${lookup mysql{SELECT secret FROM batv_prvs WHERE \
439 sender='${quote_mysql:$prvscheck_address}'}{$value}}
443 # Bounces: drop unsigned addresses for BATV senders
444 deny message = This address does not send an unsigned reverse path.
446 recipients = +batv_recipients
448 # Bounces: In case of prvs-signed address, check signature.
449 deny message = Invalid reverse path signature.
451 condition = ${prvscheck {$local_part@$domain}{PRVSCHECK_SQL}{1}}
452 !condition = $prvscheck_result
458 data = ${prvscheck {$local_part@$domain}{PRVSCHECK_SQL}{}}
460 Transport (referenced by router that makes decision if
465 return_path = ${prvs {$return_path} \
466 {${lookup mysql{SELECT \
467 secret FROM batv_prvs WHERE \
468 sender='${quote_mysql:$sender_address}'} \
471 PH/04 There are two new options that control the retrying done by the daemon
472 at startup when it cannot immediately bind a socket (typically because
473 the socket is already in use). The default values reproduce what were
474 built-in constants previously: daemon_startup_retries defines the number
475 of retries after the first failure (default 9); daemon_startup_sleep
476 defines the length of time to wait between retries (default 30s).
478 PH/05 There is now a new ${if condition called "match_ip". It is similar to
479 match_domain, etc. It must be followed by two argument strings. The first
480 (after expansion) must be an IP address or an empty string. The second
481 (after expansion) is a restricted host list that can match only an IP
482 address, not a host name. For example:
484 ${if match_ip{$sender_host_address}{1.2.3.4:5.6.7.8}{...}{...}}
486 The specific types of host list item that are permitted in the list are
487 shown below. Consult the manual section on host lists for further
490 . An IP address, optionally with a CIDR mask.
492 . A single asterisk matches any IP address.
494 . An empty item matches only if the IP address is empty. This could be
495 useful for testing for a locally submitted message or one from specific
496 hosts in a single test such as
498 ${if match_ip{$sender_host_address}{:4.3.2.1:...}{...}{...}}
500 where the first item in the list is the empty string.
502 . The item @[] matches any of the local host's interface addresses.
504 . Lookups are assumed to be "net-" style lookups, even if "net-" is not
505 specified. Thus, the following are equivalent:
507 ${if match_ip{$sender_host_address}{lsearch;/some/file}...
508 ${if match_ip{$sender_host_address}{net-lsearch;/some/file}...
510 You do need to specify the "net-" prefix if you want to specify a
511 specific address mask, for example, by using "net24-".
513 PH/06 The "+all" debug selector used to set the flags for all possible output;
514 it is something that people tend to use semi-automatically when
515 generating debug output for me or for the list. However, by including
516 "+memory", an awful lot of output that is very rarely of interest was
517 generated. I have changed this so that "+all" no longer includes
518 "+memory". However, "-all" still turns everything off.
524 PH/01 The format in which GnuTLS parameters are written to the gnutls-param
525 file in the spool directory has been changed. This change has been made
526 to alleviate problems that some people had with the generation of the
527 parameters by Exim when /dev/random was exhausted. In this situation,
528 Exim would hang until /dev/random acquired some more entropy.
530 The new code exports and imports the DH and RSA parameters in PEM
531 format. This means that the parameters can be generated externally using
532 the certtool command that is part of GnuTLS.
534 To replace the parameters with new ones, instead of deleting the file
535 and letting Exim re-create it, you can generate new parameters using
536 certtool and, when this has been done, replace Exim's cache file by
537 renaming. The relevant commands are something like this:
541 # chown exim:exim new.params
542 # chmod 0400 new.params
543 # certtool --generate-privkey --bits 512 >new.params
544 # echo "" >>new.params
545 # certtool --generate-dh-params --bits 1024 >> new.params
546 # mv new.params params
548 If Exim never has to generate the parameters itself, the possibility of
551 PH/02 A new expansion item for dynamically loading and calling a locally-
552 written C function is now provided, if Exim is compiled with
556 set in Local/Makefile. The facility is not included by default (a
557 suitable error is given if you try to use it when it is not there.)
559 If you enable EXPAND_DLFUNC, you should also be aware of the new redirect
560 router option forbid_filter_dlfunc. If you have unprivileged users on
561 your system who are permitted to create filter files, you might want to
562 set forbid_filter_dlfunc=true in the appropriate router, to stop them
563 using ${dlfunc to run code within Exim.
565 You load and call an external function like this:
567 ${dlfunc{/some/file}{function}{arg1}{arg2}...}
569 Once loaded, Exim remembers the dynamically loaded object so that it
570 doesn't reload the same object file in the same Exim process (but of
571 course Exim does start new processes frequently).
573 There may be from zero to eight arguments to the function. When compiling
574 a local function that is to be called in this way, local_scan.h should be
575 included. The Exim variables and functions that are defined by that API
576 are also available for dynamically loaded functions. The function itself
577 must have the following type:
579 int dlfunction(uschar **yield, int argc, uschar *argv[])
581 Where "uschar" is a typedef for "unsigned char" in local_scan.h. The
582 function should return one of the following values:
584 OK Success. The string that is placed in "yield" is put into
585 the expanded string that is being built.
587 FAIL A non-forced expansion failure occurs, with the error
588 message taken from "yield", if it is set.
590 FAIL_FORCED A forced expansion failure occurs, with the error message
591 taken from "yield" if it is set.
593 ERROR Same as FAIL, except that a panic log entry is written.
595 When compiling a function that is to be used in this way with gcc,
596 you need to add -shared to the gcc command. Also, in the Exim build-time
597 configuration, you must add -export-dynamic to EXTRALIBS.
599 TF/01 $received_time is a new expansion variable containing the time and date
600 as a number of seconds since the start of the Unix epoch when the
601 current message was received.
603 PH/03 There is a new value for RADIUS_LIB_TYPE that can be set in
604 Local/Makefile. It is RADIUSCLIENTNEW, and it requests that the new API,
605 in use from radiusclient 0.4.0 onwards, be used. It does not appear to be
606 possible to detect the different versions automatically.
608 PH/04 There is a new option called acl_not_smtp_mime that allows you to scan
609 MIME parts in non-SMTP messages. It operates in exactly the same way as
612 PH/05 It is now possible to redefine a macro within the configuration file.
613 The macro must have been previously defined within the configuration (or
614 an included file). A definition on the command line using the -D option
615 causes all definitions and redefinitions within the file to be ignored.
616 In other words, -D overrides any values that are set in the file.
617 Redefinition is specified by using '==' instead of '='. For example:
621 MAC1 == updated value
623 Redefinition does not alter the order in which the macros are applied to
624 the subsequent lines of the configuration file. It is still the same
625 order in which the macros were originally defined. All that changes is
626 the macro's value. Redefinition makes it possible to accumulate values.
631 MAC1 == MAC1 and something added
633 This can be helpful in situations where the configuration file is built
634 from a number of other files.
636 PH/06 Macros may now be defined or redefined between router, transport,
637 authenticator, or ACL definitions, as well as in the main part of the
638 configuration. They may not, however, be changed within an individual
639 driver or ACL, or in the local_scan, retry, or rewrite sections of the
642 PH/07 $acl_verify_message is now set immediately after the failure of a
643 verification in an ACL, and so is available in subsequent modifiers. In
644 particular, the message can be preserved by coding like this:
646 warn !verify = sender
647 set acl_m0 = $acl_verify_message
649 Previously, $acl_verify_message was set only while expanding "message"
650 and "log_message" when a very denied access.
652 PH/08 The redirect router has two new options, sieve_useraddress and
653 sieve_subaddress. These are passed to a Sieve filter to specify the :user
654 and :subaddress parts of an address. Both options are unset by default.
655 However, when a Sieve filter is run, if sieve_useraddress is unset, the
656 entire original local part (including any prefix or suffix) is used for
657 :user. An unset subaddress is treated as an empty subaddress.
659 PH/09 Quota values can be followed by G as well as K and M.
661 PH/10 $message_linecount is a new variable that contains the total number of
662 lines in the header and body of the message. Compare $body_linecount,
663 which is the count for the body only. During the DATA and
664 content-scanning ACLs, $message_linecount contains the number of lines
665 received. Before delivery happens (that is, before filters, routers, and
666 transports run) the count is increased to include the Received: header
667 line that Exim standardly adds, and also any other header lines that are
668 added by ACLs. The blank line that separates the message header from the
669 body is not counted. Here is an example of the use of this variable in a
672 deny message = Too many lines in message header
674 ${if <{250}{${eval: $message_linecount - $body_linecount}}}
676 In the MAIL and RCPT ACLs, the value is zero because at that stage the
677 message has not yet been received.
679 PH/11 In a ${run expansion, the variable $value (which contains the standard
680 output) is now also usable in the "else" string.
682 PH/12 In a pipe transport, although a timeout while waiting for the pipe
683 process to complete was treated as a delivery failure, a timeout while
684 writing the message to the pipe was logged, but erroneously treated as a
685 successful delivery. Such timeouts include transport filter timeouts. For
686 consistency with the overall process timeout, these timeouts are now
687 treated as errors, giving rise to delivery failures by default. However,
688 there is now a new Boolean option for the pipe transport called
689 timeout_defer, which, if set TRUE, converts the failures into defers for
690 both kinds of timeout. A transport filter timeout is now identified in
697 The documentation is up-to-date for the 4.50 release.
projects / exim.git / blob