4 This file contains descriptions of new features that have been added to Exim.
5 Before a formal release, there may be quite a lot of detail so that people can
6 test from the snapshots or the CVS before the documentation is updated. Once
7 the documentation is updated, this file is reduced to a short list.
12 1. Support for using the system standard CA bundle.
14 2. New expansion items $config_file, $config_dir, containing the file
15 and directory name of the main configuration file. Also $exim_version.
17 3. New "malware=" support for Avast.
19 4. New "spam=" variant option for Rspamd.
21 5. Assorted options on malware= and spam= scanners.
23 6. A commandline option to write a comment into the logfile.
25 7. If built with EXPERIMENTAL_SOCKS feature enabled, the smtp transport can
26 be configured to make connections via socks5 proxies.
28 8. If built with EXPERIMENTAL_INTERNATIONAL, support is included for
29 the transmission of UTF-8 envelope addresses.
31 9. If built with EXPERIMENTAL_INTERNATIONAL, an expansion item for a commonly
32 used encoding of Maildir folder names.
34 10. A logging option for slow DNS lookups.
36 11. New ${env {<variable>}} expansion.
38 12. A non-SMTP authenticator using information from TLS client certificates.
40 13. Main option "tls_eccurve" for selecting an Elliptic Curve for TLS.
41 Patch originally by Wolfgang Breyha.
43 14. Main option "dns_trust_aa" for trusting your local nameserver at the
50 1. If built with EXPERIMENTAL_DANE feature enabled, Exim will follow the
51 DANE smtp draft to assess a secure chain of trust of the certificate
52 used to establish the TLS connection based on a TLSA record in the
55 2. The EXPERIMENTAL_TPDA feature has been renamed to EXPERIMENTAL_EVENT
56 and several new events have been created. The reason is because it has
57 been expanded beyond just firing events during the transport phase. Any
58 existing TPDA transport options will have to be rewritten to use a new
59 $event_name expansion variable in a condition. Refer to the
60 experimental-spec.txt for details and examples.
62 3. The EXPERIMENTAL_CERTNAMES features is an enhancement to verify that
63 server certs used for TLS match the result of the MX lookup. It does
64 not use the same mechanism as DANE.
74 1. If built with the EXPERIMENTAL_PROXY feature enabled, Exim can be
75 configured to expect an initial header from a proxy that will make the
76 actual external source IP:host be used in exim instead of the IP of the
77 proxy that is connecting to it.
79 2. New verify option header_names_ascii, which will check to make sure
80 there are no non-ASCII characters in header names. Exim itself handles
81 those non-ASCII characters, but downstream apps may not, so Exim can
82 detect and reject if those characters are present.
84 3. New expansion operator ${utf8clean:string} to replace malformed UTF8
85 codepoints with valid ones.
87 4. New malware type "sock". Talks over a Unix or TCP socket, sending one
88 command line and matching a regex against the return data for trigger
89 and a second regex to extract malware_name. The mail spoolfile name can
90 be included in the command line.
92 5. The smtp transport now supports options "tls_verify_hosts" and
93 "tls_try_verify_hosts". If either is set the certificate verification
94 is split from the encryption operation. The default remains that a failed
95 verification cancels the encryption.
97 6. New SERVERS override of default ldap server list. In the ACLs, an ldap
98 lookup can now set a list of servers to use that is different from the
101 7. New command-line option -C for exiqgrep to specify alternate exim.conf
102 file when searching the queue.
104 8. OCSP now supports GnuTLS also, if you have version 3.1.3 or later of that.
106 9. Support for DNSSEC on outbound connections.
108 10. New variables "tls_(in,out)_(our,peer)cert" and expansion item
109 "certextract" to extract fields from them. Hash operators md5 and sha1
110 work over them for generating fingerprints, and a new sha256 operator
113 11. PRDR is now supported dy default.
115 12. OCSP stapling is now supported by default.
117 13. If built with the EXPERIMENTAL_DSN feature enabled, Exim will output
118 Delivery Status Notification messages in MIME format, and negociate
119 DSN features per RFC 3461.
125 1. New command-line option -bI:sieve will list all supported sieve extensions
126 of this Exim build on standard output, one per line.
127 ManageSieve (RFC 5804) providers managing scripts for use by Exim should
128 query this to establish the correct list to include in the protocol's
129 SIEVE capability line.
131 2. If the -n option is combined with the -bP option, then the name of an
132 emitted option is not output, only the value (if visible to you).
133 For instance, "exim -n -bP pid_file_path" should just emit a pathname
134 followed by a newline, and no other text.
136 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
137 has a "tls_dh_min_bits" option, to set the minimum acceptable number of
138 bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
139 acceptable for security. (Option accepted but ignored if using OpenSSL).
140 Defaults to 1024, the old value. May be lowered only to 512, or raised as
141 far as you like. Raising this may hinder TLS interoperability with other
142 sites and is not currently recommended. Lowering this will permit you to
143 establish a TLS session which is not as secure as you might like.
145 Unless you really know what you are doing, leave it alone.
147 4. If not built with DISABLE_DNSSEC, Exim now has the main option
148 dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
149 to send the DO flag to your recursive resolver. If you have a recursive
150 resolver, which can set the Authenticated Data (AD) flag in results, Exim
151 can now detect this. Exim does not perform validation itself, instead
152 relying upon a trusted path to the resolver.
154 Current status: work-in-progress; $sender_host_dnssec variable added.
156 5. DSCP support for outbound connections: on a transport using the smtp driver,
157 set "dscp = ef", for instance, to cause the connections to have the relevant
158 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
160 Similarly for inbound connections, there is a new control modifier, dscp,
161 so "warn control = dscp/ef" in the connect ACL, or after authentication.
163 Supported values depend upon system libraries. "exim -bI:dscp" to list the
164 ones Exim knows of. You can also set a raw number 0..0x3F.
166 6. The -G command-line flag is no longer ignored; it is now equivalent to an
167 ACL setting "control = suppress_local_fixups". The -L command-line flag
168 is now accepted and forces use of syslog, with the provided tag as the
169 process name. A few other flags used by Sendmail are now accepted and
172 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
173 ACL modifier; works for single-recipient mails which are recieved on and
174 deliverable via SMTP. Using the connection made for a recipient verify,
175 if requested before the verify, or a new one made for the purpose while
176 the inbound connection is still active. The bulk of the mail item is copied
177 direct from the inbound socket to the outbound (as well as the spool file).
178 When the source notifies the end of data, the data acceptance by the destination
179 is negociated before the acceptance is sent to the source. If the destination
180 does not accept the mail item, for example due to content-scanning, the item
181 is not accepted from the source and therefore there is no need to generate
182 a bounce mail. This is of benefit when providing a secondary-MX service.
183 The downside is that delays are under the control of the ultimate destination
186 The Recieved-by: header on items delivered by cutthrough is generated
187 early in reception rather than at the end; this will affect any timestamp
188 included. The log line showing delivery is recorded before that showing
189 reception; it uses a new ">>" tag instead of "=>".
191 To support the feature, verify-callout connections can now use ESMTP and TLS.
192 The usual smtp transport options are honoured, plus a (new, default everything)
193 hosts_verify_avoid_tls.
195 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
196 for specific access to the information for each connection. The old names
197 are present for now but deprecated.
199 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING.
201 8. New expansion operators ${listnamed:name} to get the content of a named list
202 and ${listcount:string} to count the items in a list.
204 9. New global option "gnutls_allow_auto_pkcs11", defaults false. The GnuTLS
205 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
206 modules. For some situations this is desirable, but we expect admin in
207 those situations to know they want the feature. More commonly, it means
208 that GUI user modules get loaded and are broken by the setuid Exim being
209 unable to access files specified in environment variables and passed
210 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
211 unless this new option is set.
213 Some older OS's with earlier versions of GnuTLS might not have pkcs11 ability,
214 so have also added a build option which can be used to build Exim with GnuTLS
215 but without trying to use any kind of PKCS11 support. Uncomment this in the
218 AVOID_GNUTLS_PKCS11=yes
220 10. The "acl = name" condition on an ACL now supports optional arguments.
221 New expansion item "${acl {name}{arg}...}" and expansion condition
222 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
223 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
224 Variable $acl_narg contains the number of arguments. If the ACL sets
225 a "message =" value this becomes the result of the expansion item,
226 or the value of $value for the expansion condition. If the ACL returns
227 accept the expansion condition is true; if reject, false. A defer
228 return results in a forced fail.
230 11. Routers and transports can now have multiple headers_add and headers_remove
231 option lines. The concatenated list is used.
233 12. New ACL modifier "remove_header" can remove headers before message gets
234 handled by routers/transports.
236 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
237 "aaaa" and "a" lookups is done and the full set of results returned.
239 14. New expansion variable $headers_added with content from ACL add_header
240 modifier (but not yet added to messsage).
242 15. New 8bitmime status logging option for received messages. Log field "M8S".
244 16. New authenticated_sender logging option, adding to log field "A".
246 17. New expansion variables $router_name and $transport_name. Useful
247 particularly for debug_print as -bt commandline option does not
248 require privilege whereas -d does.
250 18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
251 proposed extension to SMTP from Eric Hall.
253 19. The pipe transport has gained the force_command option, to allow
254 decorating commands from user .forward pipe aliases with prefix
255 wrappers, for instance.
257 20. Callout connections can now AUTH; the same controls as normal delivery
260 21. Support for DMARC, using opendmarc libs, can be enabled. It adds new
261 options: dmarc_forensic_sender, dmarc_history_file, and dmarc_tld_file.
262 It adds new expansion variables $dmarc_ar_header, $dmarc_status,
263 $dmarc_status_text, and $dmarc_used_domain. It adds a new acl modifier
264 dmarc_status. It adds new control flags dmarc_disable_verify and
265 dmarc_enable_forensic.
267 22. Add expansion variable $authenticated_fail_id, which is the username
268 provided to the authentication method which failed. It is available
269 for use in subsequent ACL processing (typically quit or notquit ACLs).
271 23. New ACL modifer "udpsend" can construct a UDP packet to send to a given
274 24. New ${hexquote:..string..} expansion operator converts non-printable
275 characters in the string to \xNN form.
277 25. Experimental TPDA (Transport Post Delivery Action) function added.
278 Patch provided by Axel Rau.
280 26. Experimental Redis lookup added. Patch provided by Warren Baker.
286 1. New authenticator driver, "gsasl". Server-only (at present).
287 This is a SASL interface, licensed under GPL, which can be found at
288 http://www.gnu.org/software/gsasl/.
289 This system does not provide sources of data for authentication, so
290 careful use needs to be made of the conditions in Exim.
292 2. New authenticator driver, "heimdal_gssapi". Server-only.
293 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
294 is no longer honoured for setuid programs by Heimdal. Use the
295 "server_keytab" option to point to the keytab.
297 3. The "pkg-config" system can now be used when building Exim to reference
298 cflags and library information for lookups and authenticators, rather
299 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
300 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
301 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
303 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
304 find the headers and libraries for PCRE.
306 4. New expansion variable $tls_bits.
308 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
309 be joined together with ASCII NUL characters to construct the key to pass
310 into the DBM library. Can be used with gsasl to access sasldb2 files as
313 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
315 Avoid release 1.0.1a if you can. Note that the default value of
316 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
317 increased susceptibility to attack. This may still have interoperability
318 implications for very old clients (see version 4.31 change 37) but
319 administrators can choose to make the trade-off themselves and restore
320 compatibility at the cost of session security.
322 7. Use of the new expansion variable $tls_sni in the main configuration option
323 tls_certificate will cause Exim to re-expand the option, if the client
324 sends the TLS Server Name Indication extension, to permit choosing a
325 different certificate; tls_privatekey will also be re-expanded. You must
326 still set these options to expand to valid files when $tls_sni is not set.
328 The SMTP Transport has gained the option tls_sni, which will set a hostname
329 for outbound TLS sessions, and set $tls_sni too.
331 A new log_selector, +tls_sni, has been added, to log received SNI values
332 for Exim as a server.
334 8. The existing "accept_8bitmime" option now defaults to true. This means
335 that Exim is deliberately not strictly RFC compliant. We're following
336 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
337 Those who disagree, or know that they are talking to mail servers that,
338 even today, are not 8-bit clean, need to turn off this option.
340 9. Exim can now be started with -bw (with an optional timeout, given as
341 -bw<timespec>). With this, stdin at startup is a socket that is
342 already listening for connections. This has a more modern name of
343 "socket activation", but forcing the activated socket to fd 0. We're
344 interested in adding more support for modern variants.
346 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
347 for numbers indicates multiplication by 1024^3.
349 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
350 gnutls_require_mac & gnutls_require_protocols are no longer supported.
351 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
352 string, documentation for which is at:
353 http://www.gnutls.org/manual/html_node/Priority-Strings.html
355 SNI support has been added to Exim's GnuTLS integration too.
357 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
358 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
360 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
361 is now available. If the contents of the file are valid, then Exim will
362 send that back in response to a TLS status request; this is OCSP Stapling.
363 Exim will not maintain the contents of the file in any way: administrators
364 are responsible for ensuring that it is up-to-date.
366 See "experimental-spec.txt" for more details.
368 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
369 identically to TXT record lookups.
371 14. New expansion variable $tod_epoch_l for higher-precision time.
373 15. New global option tls_dh_max_bits, defaulting to current value of NSS
374 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
375 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
377 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
378 Option can now be a path or an identifier for a standard prime.
379 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
380 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
383 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
384 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
385 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
391 1. New options for the ratelimit ACL condition: /count= and /unique=.
392 The /noupdate option has been replaced by a /readonly option.
394 2. The SMTP transport's protocol option may now be set to "smtps", to
395 use SSL-on-connect outbound.
397 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
398 there is a problem talking to the AV scanner, or the AV scanner running.
400 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
401 and check if the search item is a member of the list. This does not
402 support named lists, but does subject the list part to string expansion.
404 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
405 built, Exim no longer performs string expansion on the second string of
406 the match_* expansion conditions: "match_address", "match_domain",
407 "match_ip" & "match_local_part". Named lists can still be used.
413 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
414 or off in the resolver library.
420 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
421 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
422 libraries. The following global options have been added in support of
423 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
424 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
426 2. The pipe transport now takes a boolean option, "freeze_signal", default
427 false. When true, if the external delivery command exits on a signal then
428 Exim will freeze the message in the queue, instead of generating a bounce.
430 3. Log filenames may now use %M as an escape, instead of %D (still available).
431 The %M pattern expands to yyyymm, providing month-level resolution.
433 4. The $message_linecount variable is now updated for the maildir_tag option,
434 in the same way as $message_size, to reflect the real number of lines,
435 including any header additions or removals from transport.
437 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
438 Exim now selects entries randomly, to better scale in a cluster setup.
444 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
445 the flaw permitted the Exim run-time user to cause root to append to
446 arbitrary files of the attacker's choosing, with the content based
447 on content supplied by the attacker.
449 2. Exim now supports loading some lookup types at run-time, using your
450 platform's dlopen() functionality. This has limited platform support
451 and the intention is not to support every variant, it's limited to
452 dlopen(). This permits the main Exim binary to not be linked against
453 all the libraries needed for all the lookup types.
459 NOTE: this version is not guaranteed backwards-compatible, please read the
460 items below carefully
462 1. A new main configuration option, "openssl_options", is available if Exim
463 is built with SSL support provided by OpenSSL. The option allows
464 administrators to specify OpenSSL options to be used on connections;
465 typically this is to set bug compatibility features which the OpenSSL
466 developers have not enabled by default. There may be security
467 consequences for certain options, so these should not be changed
470 2. A new pipe transport option, "permit_coredumps", may help with problem
471 diagnosis in some scenarios. Note that Exim is typically installed as
472 a setuid binary, which on most OSes will inhibit coredumps by default,
473 so that safety mechanism would have to be overridden for this option to
474 be able to take effect.
476 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
477 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
478 Note that this switches Exim to use a new API ("INSTREAM") and a future
479 release of ClamAV will remove support for the old API ("STREAM").
481 The av_scanner option, when set to "clamd", now takes an optional third
482 part, "local", which causes Exim to pass a filename to ClamAV instead of
483 the file content. This is the same behaviour as when clamd is pointed at
484 a Unix-domain socket. For example:
486 av_scanner = clamd:192.0.2.3 1234:local
488 ClamAV's ExtendedDetectionInfo response format is now handled.
490 4. There is now a -bmalware option, restricted to admin users. This option
491 takes one parameter, a filename, and scans that file with Exim's
492 malware-scanning framework. This is intended purely as a debugging aid
493 to ensure that Exim's scanning is working, not to replace other tools.
494 Note that the ACL framework is not invoked, so if av_scanner references
495 ACL variables without a fallback then this will fail.
497 5. There is a new expansion operator, "reverse_ip", which will reverse IP
498 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
500 ${reverse_ip:192.0.2.4}
502 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
503 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
505 6. There is a new ACL control called "debug", to enable debug logging.
506 This allows selective logging of certain incoming transactions within
507 production environments, with some care. It takes two options, "tag"
508 and "opts"; "tag" is included in the filename of the log and "opts"
509 is used as per the -d<options> command-line option. Examples, which
510 don't all make sense in all contexts:
513 control = debug/tag=.$sender_host_address
514 control = debug/opts=+expand+acl
515 control = debug/tag=.$message_exim_id/opts=+expand
517 7. It has always been implicit in the design and the documentation that
518 "the Exim user" is not root. src/EDITME said that using root was
519 "very strongly discouraged". This is not enough to keep people from
520 shooting themselves in the foot in days when many don't configure Exim
521 themselves but via package build managers. The security consequences of
522 running various bits of network code are severe if there should be bugs in
523 them. As such, the Exim user may no longer be root. If configured
524 statically, Exim will refuse to build. If configured as ref:user then Exim
525 will exit shortly after start-up. If you must shoot yourself in the foot,
526 then henceforth you will have to maintain your own local patches to strip
529 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
530 condition logic to determine truth/failure and will fail to expand many
531 strings, bool_lax{} uses the router condition logic, where most strings
533 Note: bool{00} is false, bool_lax{00} is true.
535 9. Routers now support multiple "condition" tests.
537 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
538 Setting this allows an admin to define which entry in the tcpwrappers
539 config file will be used to control access to the daemon. This option
540 is only available when Exim is built with USE_TCP_WRAPPERS. The
541 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
544 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
545 the Exim run-time user, instead of root.
547 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
548 is forced on. This is mitigated by the new build option
549 TRUSTED_CONFIG_LIST which defines a list of configuration files which
550 are trusted; one per line. If a config file is owned by root and matches
551 a pathname in the list, then it may be invoked by the Exim build-time
552 user without Exim relinquishing root privileges.
554 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
555 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
556 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
557 include the main config. As a transition mechanism, we are temporarily
558 providing a work-around: the new build option WHITELIST_D_MACROS provides
559 a colon-separated list of macro names which may be overridden by the Exim
560 run-time user. The values of these macros are constrained to the regex
561 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
567 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
568 writable, the other to locking of MBX folders (not mbox).
570 2. MySQL stored procedures are now supported.
572 3. The dkim_domain transport option is now a list, not a single string, and
573 messages will be signed for each element in the list (discarding
576 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
577 in the presence of multiple character strings within the RR. Prior to 4.70,
578 only the first string would be returned. The dnsdb lookup now, by default,
579 preserves the pre-4.70 semantics, but also now takes an extended output
580 separator specification. The separator can be followed by a semicolon, to
581 concatenate the individual text strings together with no join character,
582 or by a comma and a second separator character, in which case the text
583 strings within a TXT record are joined on that second character.
584 Administrators are reminded that DNS provides no ordering guarantees
585 between multiple records in an RRset. For example:
587 foo.example. IN TXT "a" "b" "c"
588 foo.example. IN TXT "d" "e" "f"
590 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
591 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
592 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
598 1. Native DKIM support without an external library.
599 (Note that if no action to prevent it is taken, a straight upgrade will
600 result in DKIM verification of all signed incoming emails. See spec
601 for details on conditionally disabling)
603 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
605 3. There is now a bool{} expansion condition which maps certain strings to
606 true/false condition values (most likely of use in conjunction with the
607 and{} expansion operator).
609 4. The $spam_score, $spam_bar and $spam_report variables are now available
612 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
613 options, provided that Exim is invoked by an admin_user.
615 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
616 which increases compatibility with older clients at the cost of decreased
617 security. Don't set this unless you need to support such clients.
619 7. There is a new expansion operator, ${randint:...} which will produce a
620 "random" number less than the supplied integer. This randomness is
621 not guaranteed to be cryptographically strong, but depending upon how
622 Exim was built may be better than the most naive schemes.
624 8. Exim now explicitly ensures that SHA256 is available when linked against
627 9. The transport_filter_timeout option now applies to SMTP transports too.
633 1. Preliminary DKIM support in Experimental.
639 1. The body_linecount and body_zerocount C variables are now exported in the
642 2. When a dnslists lookup succeeds, the key that was looked up is now placed
643 in $dnslist_matched. When the key is an IP address, it is not reversed in
644 this variable (though it is, of course, in the actual lookup). In simple
647 deny dnslists = spamhaus.example
649 the key is also available in another variable (in this case,
650 $sender_host_address). In more complicated cases, however, this is not
651 true. For example, using a data lookup might generate a dnslists lookup
654 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
656 If this condition succeeds, the value in $dnslist_matched might be
657 192.168.6.7 (for example).
659 3. Authenticators now have a client_condition option. When Exim is running as
660 a client, it skips an authenticator whose client_condition expansion yields
661 "0", "no", or "false". This can be used, for example, to skip plain text
662 authenticators when the connection is not encrypted by a setting such as:
664 client_condition = ${if !eq{$tls_cipher}{}}
666 Note that the 4.67 documentation states that $tls_cipher contains the
667 cipher used for incoming messages. In fact, during SMTP delivery, it
668 contains the cipher used for the delivery. The same is true for
671 4. There is now a -Mvc <message-id> option, which outputs a copy of the
672 message to the standard output, in RFC 2822 format. The option can be used
673 only by an admin user.
675 5. There is now a /noupdate option for the ratelimit ACL condition. It
676 computes the rate and checks the limit as normal, but it does not update
677 the saved data. This means that, in relevant ACLs, it is possible to lookup
678 the existence of a specified (or auto-generated) ratelimit key without
679 incrementing the ratelimit counter for that key.
681 In order for this to be useful, another ACL entry must set the rate
682 for the same key somewhere (otherwise it will always be zero).
687 # Read the rate; if it doesn't exist or is below the maximum
689 deny ratelimit = 100 / 5m / strict / noupdate
690 log_message = RATE: $sender_rate / $sender_rate_period \
691 (max $sender_rate_limit)
693 [... some other logic and tests...]
695 warn ratelimit = 100 / 5m / strict / per_cmd
696 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
697 (max $sender_rate_limit)
698 condition = ${if le{$sender_rate}{$sender_rate_limit}}
702 6. The variable $max_received_linelength contains the number of bytes in the
703 longest line that was received as part of the message, not counting the
704 line termination character(s).
706 7. Host lists can now include +ignore_defer and +include_defer, analagous to
707 +ignore_unknown and +include_unknown. These options should be used with
708 care, probably only in non-critical host lists such as whitelists.
710 8. There's a new option called queue_only_load_latch, which defaults true.
711 If set false when queue_only_load is greater than zero, Exim re-evaluates
712 the load for each incoming message in an SMTP session. Otherwise, once one
713 message is queued, the remainder are also.
715 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
716 cases when an SMTP session ends without sending QUIT. However, when Exim
717 itself is is bad trouble, such as being unable to write to its log files,
718 this ACL is not run, because it might try to do things (such as write to
719 log files) that make the situation even worse.
721 Like the QUIT ACL, this new ACL is provided to make it possible to gather
722 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
723 modifier is forbidden in this ACL.
725 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
726 to a string that indicates the reason for the termination of the SMTP
727 connection. The possible values are:
729 acl-drop Another ACL issued a "drop" command
730 bad-commands Too many unknown or non-mail commands
731 command-timeout Timeout while reading SMTP commands
732 connection-lost The SMTP connection has been lost
733 data-timeout Timeout while reading message data
734 local-scan-error The local_scan() function crashed
735 local-scan-timeout The local_scan() function timed out
736 signal-exit SIGTERM or SIGINT
737 synchronization-error SMTP synchronization error
738 tls-failed TLS failed to start
740 In most cases when an SMTP connection is closed without having received
741 QUIT, Exim sends an SMTP response message before actually closing the
742 connection. With the exception of acl-drop, the default message can be
743 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
744 "drop" verb in another ACL, it is the message from the other ACL that is
747 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
748 servers with individual queries. This is done by starting the query with
749 "servers=x:y:z;", where each item in the list may take one of two forms:
751 (1) If it is just a host name, the appropriate global option (mysql_servers
752 or pgsql_servers) is searched for a host of the same name, and the
753 remaining parameters (database, user, password) are taken from there.
755 (2) If it contains any slashes, it is taken as a complete parameter set.
757 The list of servers is used in exactly the same was as the global list.
758 Once a connection to a server has happened and a query has been
759 successfully executed, processing of the lookup ceases.
761 This feature is intended for use in master/slave situations where updates
762 are occurring, and one wants to update a master rather than a slave. If the
763 masters are in the list for reading, you might have:
765 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
767 In an updating lookup, you could then write
769 ${lookup mysql{servers=master; UPDATE ...}
771 If, on the other hand, the master is not to be used for reading lookups:
773 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
775 you can still update the master by
777 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
779 11. The message_body_newlines option (default FALSE, for backwards
780 compatibility) can be used to control whether newlines are present in
781 $message_body and $message_body_end. If it is FALSE, they are replaced by
788 1. There is a new log selector called smtp_no_mail, which is not included in
789 the default setting. When it is set, a line is written to the main log
790 whenever an accepted SMTP connection terminates without having issued a
793 2. When an item in a dnslists list is followed by = and & and a list of IP
794 addresses, the behaviour was not clear when the lookup returned more than
795 one IP address. This has been solved by the addition of == and =& for "all"
796 rather than the default "any" matching.
798 3. Up till now, the only control over which cipher suites GnuTLS uses has been
799 for the cipher algorithms. New options have been added to allow some of the
800 other parameters to be varied.
802 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
803 set, Exim compiles a runtime option called disable_fsync.
805 5. There is a new variable called $smtp_count_at_connection_start.
807 6. There's a new control called no_pipelining.
809 7. There are two new variables called $sending_ip_address and $sending_port.
810 These are set whenever an SMTP connection to another host has been set up.
812 8. The expansion of the helo_data option in the smtp transport now happens
813 after the connection to the server has been made.
815 9. There is a new expansion operator ${rfc2047d: that decodes strings that
816 are encoded as per RFC 2047.
818 10. There is a new log selector called "pid", which causes the current process
819 id to be added to every log line, in square brackets, immediately after the
822 11. Exim has been modified so that it flushes SMTP output before implementing
823 a delay in an ACL. It also flushes the output before performing a callout,
824 as this can take a substantial time. These behaviours can be disabled by
825 obeying control = no_delay_flush or control = no_callout_flush,
826 respectively, at some earlier stage of the connection.
828 12. There are two new expansion conditions that iterate over a list. They are
829 called forany and forall.
831 13. There's a new global option called dsn_from that can be used to vary the
832 contents of From: lines in bounces and other automatically generated
833 messages ("delivery status notifications" - hence the name of the option).
835 14. The smtp transport has a new option called hosts_avoid_pipelining.
837 15. By default, exigrep does case-insensitive matches. There is now a -I option
838 that makes it case-sensitive.
840 16. A number of new features ("addresses", "map", "filter", and "reduce") have
841 been added to string expansions to make it easier to process lists of
842 items, typically addresses.
844 17. There's a new ACL modifier called "continue". It does nothing of itself,
845 and processing of the ACL always continues with the next condition or
846 modifier. It is provided so that the side effects of expanding its argument
849 18. It is now possible to use newline and other control characters (those with
850 values less than 32, plus DEL) as separators in lists.
852 19. The exigrep utility now has a -v option, which inverts the matching
855 20. The host_find_failed option in the manualroute router can now be set to
862 No new features were added to 4.66.
868 No new features were added to 4.65.
874 1. ACL variables can now be given arbitrary names, as long as they start with
875 "acl_c" or "acl_m" (for connection variables and message variables), are at
876 least six characters long, with the sixth character being either a digit or
879 2. There is a new ACL modifier called log_reject_target. It makes it possible
880 to specify which logs are used for messages about ACL rejections.
882 3. There is a new authenticator called "dovecot". This is an interface to the
883 authentication facility of the Dovecot POP/IMAP server, which can support a
884 number of authentication methods.
886 4. The variable $message_headers_raw provides a concatenation of all the
887 messages's headers without any decoding. This is in contrast to
888 $message_headers, which does RFC2047 decoding on the header contents.
890 5. In a DNS black list, if two domain names, comma-separated, are given, the
891 second is used first to do an initial check, making use of any IP value
892 restrictions that are set. If there is a match, the first domain is used,
893 without any IP value restrictions, to get the TXT record.
895 6. All authenticators now have a server_condition option.
897 7. There is a new command-line option called -Mset. It is useful only in
898 conjunction with -be (that is, when testing string expansions). It must be
899 followed by a message id; Exim loads the given message from its spool
900 before doing the expansions.
902 8. Another similar new command-line option is called -bem. It operates like
903 -be except that it must be followed by the name of a file that contains a
906 9. When an address is delayed because of a 4xx response to a RCPT command, it
907 is now the combination of sender and recipient that is delayed in
908 subsequent queue runs until its retry time is reached.
910 10. Unary negation and the bitwise logical operators and, or, xor, not, and
911 shift, have been added to the eval: and eval10: expansion items.
913 11. The variables $interface_address and $interface_port have been renamed
914 as $received_ip_address and $received_port, to make it clear that they
915 relate to message reception rather than delivery. (The old names remain
916 available for compatibility.)
918 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
919 to vary the message that is sent when an SMTP command is accepted.
925 1. There is a new Boolean option called filter_prepend_home for the redirect
928 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
929 start of receiving a non-SMTP message, before any of the message has been
932 3. When an SMTP error message is specified in a "message" modifier in an ACL,
933 or in a :fail: or :defer: message in a redirect router, Exim now checks the
934 start of the message for an SMTP error code.
936 4. There is a new parameter for LDAP lookups called "referrals", which takes
937 one of the settings "follow" (the default) or "nofollow".
939 5. Version 20070721.2 of exipick now included, offering these new options:
941 After all other sorting options have bee processed, reverse order
942 before displaying messages (-R is synonym).
944 Randomize order of matching messages before displaying.
946 Instead of displaying the matching messages, display the sum
948 --sort <variable>[,<variable>...]
949 Before displaying matching messages, sort the messages according to
950 each messages value for each variable.
952 Negate the value for every test (returns inverse output from the
953 same criteria without --not).
959 1. The ${readsocket expansion item now supports Internet domain sockets as well
960 as Unix domain sockets. If the first argument begins "inet:", it must be of
961 the form "inet:host:port". The port is mandatory; it may be a number or the
962 name of a TCP port in /etc/services. The host may be a name, or it may be an
963 IP address. An ip address may optionally be enclosed in square brackets.
964 This is best for IPv6 addresses. For example:
966 ${readsocket{inet:[::1]:1234}{<request data>}...
968 Only a single host name may be given, but if looking it up yield more than
969 one IP address, they are each tried in turn until a connection is made. Once
970 a connection has been made, the behaviour is as for ${readsocket with a Unix
973 2. If a redirect router sets up file or pipe deliveries for more than one
974 incoming address, and the relevant transport has batch_max set greater than
975 one, a batch delivery now occurs.
977 3. The appendfile transport has a new option called maildirfolder_create_regex.
978 Its value is a regular expression. For a maildir delivery, this is matched
979 against the maildir directory; if it matches, Exim ensures that a
980 maildirfolder file is created alongside the new, cur, and tmp directories.
986 The documentation is up-to-date for the 4.61 release. Major new features since
987 the 4.60 release are:
989 . An option called disable_ipv6, to disable the use of IPv6 completely.
991 . An increase in the number of ACL variables to 20 of each type.
993 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
994 $2, $3, (though those are still set) because the numeric variables get used
995 for other things in complicated expansions.
997 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
999 . It is possible to use setclassresources() on some BSD OS to control the
1000 resources used in pipe deliveries.
1002 . A new ACL modifier called add_header, which can be used with any verb.
1004 . More errors are detectable in retry rules.
1006 There are a number of other additions too.
1012 The documentation is up-to-date for the 4.60 release. Major new features since
1013 the 4.50 release are:
1015 . Support for SQLite.
1017 . Support for IGNOREQUOTA in LMTP.
1019 . Extensions to the "submission mode" features.
1021 . Support for Client SMTP Authorization (CSA).
1023 . Support for ratelimiting hosts and users.
1025 . New expansion items to help with the BATV "prvs" scheme.
1027 . A "match_ip" condition, that matches an IP address against a list.
1029 There are many more minor changes.
git://git.exim.org / exim.git / blob