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. If built with EXPERIMENTAL_DANE feature enabled, Exim will follow the
13 DANE smtp draft to assess a secure chain of trust of the certificate
14 used to establish the TLS connection based on a TLSA record in the
17 2. The EXPERIMENTAL_TPDA feature has been renamed to EXPERIMENTAL_EVENT
18 and several new events have been created. The reason is because it has
19 been expanded beyond just firing events during the transport phase. Any
20 existing TPDA transport options will have to be rewritten to use a new
21 $event_name expansion variable in a condition. Refer to the
22 experimental-spec.txt for details and examples.
24 3. The EXPERIMENTAL_CERTNAMES features is an enhancement to verify that
25 server certs used for TLS match the result of the MX lookup. It does
26 not use the same mechanism as DANE.
28 4. New expansion items $config_file, $config_dir, containing the file
29 and directory name of the main configuration file.
39 1. If built with the EXPERIMENTAL_PROXY feature enabled, Exim can be
40 configured to expect an initial header from a proxy that will make the
41 actual external source IP:host be used in exim instead of the IP of the
42 proxy that is connecting to it.
44 2. New verify option header_names_ascii, which will check to make sure
45 there are no non-ASCII characters in header names. Exim itself handles
46 those non-ASCII characters, but downstream apps may not, so Exim can
47 detect and reject if those characters are present.
49 3. New expansion operator ${utf8clean:string} to replace malformed UTF8
50 codepoints with valid ones.
52 4. New malware type "sock". Talks over a Unix or TCP socket, sending one
53 command line and matching a regex against the return data for trigger
54 and a second regex to extract malware_name. The mail spoolfile name can
55 be included in the command line.
57 5. The smtp transport now supports options "tls_verify_hosts" and
58 "tls_try_verify_hosts". If either is set the certificate verification
59 is split from the encryption operation. The default remains that a failed
60 verification cancels the encryption.
62 6. New SERVERS override of default ldap server list. In the ACLs, an ldap
63 lookup can now set a list of servers to use that is different from the
66 7. New command-line option -C for exiqgrep to specify alternate exim.conf
67 file when searching the queue.
69 8. OCSP now supports GnuTLS also, if you have version 3.1.3 or later of that.
71 9. Support for DNSSEC on outbound connections.
73 10. New variables "tls_(in,out)_(our,peer)cert" and expansion item
74 "certextract" to extract fields from them. Hash operators md5 and sha1
75 work over them for generating fingerprints, and a new sha256 operator
78 11. PRDR is now supported dy default.
80 12. OCSP stapling is now supported by default.
82 13. If built with the EXPERIMENTAL_DSN feature enabled, Exim will output
83 Delivery Status Notification messages in MIME format, and negociate
84 DSN features per RFC 3461.
90 1. New command-line option -bI:sieve will list all supported sieve extensions
91 of this Exim build on standard output, one per line.
92 ManageSieve (RFC 5804) providers managing scripts for use by Exim should
93 query this to establish the correct list to include in the protocol's
94 SIEVE capability line.
96 2. If the -n option is combined with the -bP option, then the name of an
97 emitted option is not output, only the value (if visible to you).
98 For instance, "exim -n -bP pid_file_path" should just emit a pathname
99 followed by a newline, and no other text.
101 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
102 has a "tls_dh_min_bits" option, to set the minimum acceptable number of
103 bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
104 acceptable for security. (Option accepted but ignored if using OpenSSL).
105 Defaults to 1024, the old value. May be lowered only to 512, or raised as
106 far as you like. Raising this may hinder TLS interoperability with other
107 sites and is not currently recommended. Lowering this will permit you to
108 establish a TLS session which is not as secure as you might like.
110 Unless you really know what you are doing, leave it alone.
112 4. If not built with DISABLE_DNSSEC, Exim now has the main option
113 dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
114 to send the DO flag to your recursive resolver. If you have a recursive
115 resolver, which can set the Authenticated Data (AD) flag in results, Exim
116 can now detect this. Exim does not perform validation itself, instead
117 relying upon a trusted path to the resolver.
119 Current status: work-in-progress; $sender_host_dnssec variable added.
121 5. DSCP support for outbound connections: on a transport using the smtp driver,
122 set "dscp = ef", for instance, to cause the connections to have the relevant
123 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
125 Similarly for inbound connections, there is a new control modifier, dscp,
126 so "warn control = dscp/ef" in the connect ACL, or after authentication.
128 Supported values depend upon system libraries. "exim -bI:dscp" to list the
129 ones Exim knows of. You can also set a raw number 0..0x3F.
131 6. The -G command-line flag is no longer ignored; it is now equivalent to an
132 ACL setting "control = suppress_local_fixups". The -L command-line flag
133 is now accepted and forces use of syslog, with the provided tag as the
134 process name. A few other flags used by Sendmail are now accepted and
137 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
138 ACL modifier; works for single-recipient mails which are recieved on and
139 deliverable via SMTP. Using the connection made for a recipient verify,
140 if requested before the verify, or a new one made for the purpose while
141 the inbound connection is still active. The bulk of the mail item is copied
142 direct from the inbound socket to the outbound (as well as the spool file).
143 When the source notifies the end of data, the data acceptance by the destination
144 is negociated before the acceptance is sent to the source. If the destination
145 does not accept the mail item, for example due to content-scanning, the item
146 is not accepted from the source and therefore there is no need to generate
147 a bounce mail. This is of benefit when providing a secondary-MX service.
148 The downside is that delays are under the control of the ultimate destination
151 The Recieved-by: header on items delivered by cutthrough is generated
152 early in reception rather than at the end; this will affect any timestamp
153 included. The log line showing delivery is recorded before that showing
154 reception; it uses a new ">>" tag instead of "=>".
156 To support the feature, verify-callout connections can now use ESMTP and TLS.
157 The usual smtp transport options are honoured, plus a (new, default everything)
158 hosts_verify_avoid_tls.
160 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
161 for specific access to the information for each connection. The old names
162 are present for now but deprecated.
164 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING.
166 8. New expansion operators ${listnamed:name} to get the content of a named list
167 and ${listcount:string} to count the items in a list.
169 9. New global option "gnutls_allow_auto_pkcs11", defaults false. The GnuTLS
170 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
171 modules. For some situations this is desirable, but we expect admin in
172 those situations to know they want the feature. More commonly, it means
173 that GUI user modules get loaded and are broken by the setuid Exim being
174 unable to access files specified in environment variables and passed
175 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
176 unless this new option is set.
178 Some older OS's with earlier versions of GnuTLS might not have pkcs11 ability,
179 so have also added a build option which can be used to build Exim with GnuTLS
180 but without trying to use any kind of PKCS11 support. Uncomment this in the
183 AVOID_GNUTLS_PKCS11=yes
185 10. The "acl = name" condition on an ACL now supports optional arguments.
186 New expansion item "${acl {name}{arg}...}" and expansion condition
187 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
188 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
189 Variable $acl_narg contains the number of arguments. If the ACL sets
190 a "message =" value this becomes the result of the expansion item,
191 or the value of $value for the expansion condition. If the ACL returns
192 accept the expansion condition is true; if reject, false. A defer
193 return results in a forced fail.
195 11. Routers and transports can now have multiple headers_add and headers_remove
196 option lines. The concatenated list is used.
198 12. New ACL modifier "remove_header" can remove headers before message gets
199 handled by routers/transports.
201 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
202 "aaaa" and "a" lookups is done and the full set of results returned.
204 14. New expansion variable $headers_added with content from ACL add_header
205 modifier (but not yet added to messsage).
207 15. New 8bitmime status logging option for received messages. Log field "M8S".
209 16. New authenticated_sender logging option, adding to log field "A".
211 17. New expansion variables $router_name and $transport_name. Useful
212 particularly for debug_print as -bt commandline option does not
213 require privilege whereas -d does.
215 18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
216 proposed extension to SMTP from Eric Hall.
218 19. The pipe transport has gained the force_command option, to allow
219 decorating commands from user .forward pipe aliases with prefix
220 wrappers, for instance.
222 20. Callout connections can now AUTH; the same controls as normal delivery
225 21. Support for DMARC, using opendmarc libs, can be enabled. It adds new
226 options: dmarc_forensic_sender, dmarc_history_file, and dmarc_tld_file.
227 It adds new expansion variables $dmarc_ar_header, $dmarc_status,
228 $dmarc_status_text, and $dmarc_used_domain. It adds a new acl modifier
229 dmarc_status. It adds new control flags dmarc_disable_verify and
230 dmarc_enable_forensic.
232 22. Add expansion variable $authenticated_fail_id, which is the username
233 provided to the authentication method which failed. It is available
234 for use in subsequent ACL processing (typically quit or notquit ACLs).
236 23. New ACL modifer "udpsend" can construct a UDP packet to send to a given
239 24. New ${hexquote:..string..} expansion operator converts non-printable
240 characters in the string to \xNN form.
242 25. Experimental TPDA (Transport Post Delivery Action) function added.
243 Patch provided by Axel Rau.
245 26. Experimental Redis lookup added. Patch provided by Warren Baker.
251 1. New authenticator driver, "gsasl". Server-only (at present).
252 This is a SASL interface, licensed under GPL, which can be found at
253 http://www.gnu.org/software/gsasl/.
254 This system does not provide sources of data for authentication, so
255 careful use needs to be made of the conditions in Exim.
257 2. New authenticator driver, "heimdal_gssapi". Server-only.
258 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
259 is no longer honoured for setuid programs by Heimdal. Use the
260 "server_keytab" option to point to the keytab.
262 3. The "pkg-config" system can now be used when building Exim to reference
263 cflags and library information for lookups and authenticators, rather
264 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
265 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
266 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
268 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
269 find the headers and libraries for PCRE.
271 4. New expansion variable $tls_bits.
273 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
274 be joined together with ASCII NUL characters to construct the key to pass
275 into the DBM library. Can be used with gsasl to access sasldb2 files as
278 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
280 Avoid release 1.0.1a if you can. Note that the default value of
281 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
282 increased susceptibility to attack. This may still have interoperability
283 implications for very old clients (see version 4.31 change 37) but
284 administrators can choose to make the trade-off themselves and restore
285 compatibility at the cost of session security.
287 7. Use of the new expansion variable $tls_sni in the main configuration option
288 tls_certificate will cause Exim to re-expand the option, if the client
289 sends the TLS Server Name Indication extension, to permit choosing a
290 different certificate; tls_privatekey will also be re-expanded. You must
291 still set these options to expand to valid files when $tls_sni is not set.
293 The SMTP Transport has gained the option tls_sni, which will set a hostname
294 for outbound TLS sessions, and set $tls_sni too.
296 A new log_selector, +tls_sni, has been added, to log received SNI values
297 for Exim as a server.
299 8. The existing "accept_8bitmime" option now defaults to true. This means
300 that Exim is deliberately not strictly RFC compliant. We're following
301 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
302 Those who disagree, or know that they are talking to mail servers that,
303 even today, are not 8-bit clean, need to turn off this option.
305 9. Exim can now be started with -bw (with an optional timeout, given as
306 -bw<timespec>). With this, stdin at startup is a socket that is
307 already listening for connections. This has a more modern name of
308 "socket activation", but forcing the activated socket to fd 0. We're
309 interested in adding more support for modern variants.
311 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
312 for numbers indicates multiplication by 1024^3.
314 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
315 gnutls_require_mac & gnutls_require_protocols are no longer supported.
316 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
317 string, documentation for which is at:
318 http://www.gnutls.org/manual/html_node/Priority-Strings.html
320 SNI support has been added to Exim's GnuTLS integration too.
322 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
323 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
325 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
326 is now available. If the contents of the file are valid, then Exim will
327 send that back in response to a TLS status request; this is OCSP Stapling.
328 Exim will not maintain the contents of the file in any way: administrators
329 are responsible for ensuring that it is up-to-date.
331 See "experimental-spec.txt" for more details.
333 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
334 identically to TXT record lookups.
336 14. New expansion variable $tod_epoch_l for higher-precision time.
338 15. New global option tls_dh_max_bits, defaulting to current value of NSS
339 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
340 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
342 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
343 Option can now be a path or an identifier for a standard prime.
344 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
345 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
348 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
349 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
350 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
356 1. New options for the ratelimit ACL condition: /count= and /unique=.
357 The /noupdate option has been replaced by a /readonly option.
359 2. The SMTP transport's protocol option may now be set to "smtps", to
360 use SSL-on-connect outbound.
362 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
363 there is a problem talking to the AV scanner, or the AV scanner running.
365 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
366 and check if the search item is a member of the list. This does not
367 support named lists, but does subject the list part to string expansion.
369 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
370 built, Exim no longer performs string expansion on the second string of
371 the match_* expansion conditions: "match_address", "match_domain",
372 "match_ip" & "match_local_part". Named lists can still be used.
378 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
379 or off in the resolver library.
385 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
386 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
387 libraries. The following global options have been added in support of
388 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
389 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
391 2. The pipe transport now takes a boolean option, "freeze_signal", default
392 false. When true, if the external delivery command exits on a signal then
393 Exim will freeze the message in the queue, instead of generating a bounce.
395 3. Log filenames may now use %M as an escape, instead of %D (still available).
396 The %M pattern expands to yyyymm, providing month-level resolution.
398 4. The $message_linecount variable is now updated for the maildir_tag option,
399 in the same way as $message_size, to reflect the real number of lines,
400 including any header additions or removals from transport.
402 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
403 Exim now selects entries randomly, to better scale in a cluster setup.
409 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
410 the flaw permitted the Exim run-time user to cause root to append to
411 arbitrary files of the attacker's choosing, with the content based
412 on content supplied by the attacker.
414 2. Exim now supports loading some lookup types at run-time, using your
415 platform's dlopen() functionality. This has limited platform support
416 and the intention is not to support every variant, it's limited to
417 dlopen(). This permits the main Exim binary to not be linked against
418 all the libraries needed for all the lookup types.
424 NOTE: this version is not guaranteed backwards-compatible, please read the
425 items below carefully
427 1. A new main configuration option, "openssl_options", is available if Exim
428 is built with SSL support provided by OpenSSL. The option allows
429 administrators to specify OpenSSL options to be used on connections;
430 typically this is to set bug compatibility features which the OpenSSL
431 developers have not enabled by default. There may be security
432 consequences for certain options, so these should not be changed
435 2. A new pipe transport option, "permit_coredumps", may help with problem
436 diagnosis in some scenarios. Note that Exim is typically installed as
437 a setuid binary, which on most OSes will inhibit coredumps by default,
438 so that safety mechanism would have to be overridden for this option to
439 be able to take effect.
441 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
442 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
443 Note that this switches Exim to use a new API ("INSTREAM") and a future
444 release of ClamAV will remove support for the old API ("STREAM").
446 The av_scanner option, when set to "clamd", now takes an optional third
447 part, "local", which causes Exim to pass a filename to ClamAV instead of
448 the file content. This is the same behaviour as when clamd is pointed at
449 a Unix-domain socket. For example:
451 av_scanner = clamd:192.0.2.3 1234:local
453 ClamAV's ExtendedDetectionInfo response format is now handled.
455 4. There is now a -bmalware option, restricted to admin users. This option
456 takes one parameter, a filename, and scans that file with Exim's
457 malware-scanning framework. This is intended purely as a debugging aid
458 to ensure that Exim's scanning is working, not to replace other tools.
459 Note that the ACL framework is not invoked, so if av_scanner references
460 ACL variables without a fallback then this will fail.
462 5. There is a new expansion operator, "reverse_ip", which will reverse IP
463 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
465 ${reverse_ip:192.0.2.4}
467 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
468 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
470 6. There is a new ACL control called "debug", to enable debug logging.
471 This allows selective logging of certain incoming transactions within
472 production environments, with some care. It takes two options, "tag"
473 and "opts"; "tag" is included in the filename of the log and "opts"
474 is used as per the -d<options> command-line option. Examples, which
475 don't all make sense in all contexts:
478 control = debug/tag=.$sender_host_address
479 control = debug/opts=+expand+acl
480 control = debug/tag=.$message_exim_id/opts=+expand
482 7. It has always been implicit in the design and the documentation that
483 "the Exim user" is not root. src/EDITME said that using root was
484 "very strongly discouraged". This is not enough to keep people from
485 shooting themselves in the foot in days when many don't configure Exim
486 themselves but via package build managers. The security consequences of
487 running various bits of network code are severe if there should be bugs in
488 them. As such, the Exim user may no longer be root. If configured
489 statically, Exim will refuse to build. If configured as ref:user then Exim
490 will exit shortly after start-up. If you must shoot yourself in the foot,
491 then henceforth you will have to maintain your own local patches to strip
494 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
495 condition logic to determine truth/failure and will fail to expand many
496 strings, bool_lax{} uses the router condition logic, where most strings
498 Note: bool{00} is false, bool_lax{00} is true.
500 9. Routers now support multiple "condition" tests.
502 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
503 Setting this allows an admin to define which entry in the tcpwrappers
504 config file will be used to control access to the daemon. This option
505 is only available when Exim is built with USE_TCP_WRAPPERS. The
506 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
509 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
510 the Exim run-time user, instead of root.
512 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
513 is forced on. This is mitigated by the new build option
514 TRUSTED_CONFIG_LIST which defines a list of configuration files which
515 are trusted; one per line. If a config file is owned by root and matches
516 a pathname in the list, then it may be invoked by the Exim build-time
517 user without Exim relinquishing root privileges.
519 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
520 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
521 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
522 include the main config. As a transition mechanism, we are temporarily
523 providing a work-around: the new build option WHITELIST_D_MACROS provides
524 a colon-separated list of macro names which may be overridden by the Exim
525 run-time user. The values of these macros are constrained to the regex
526 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
532 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
533 writable, the other to locking of MBX folders (not mbox).
535 2. MySQL stored procedures are now supported.
537 3. The dkim_domain transport option is now a list, not a single string, and
538 messages will be signed for each element in the list (discarding
541 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
542 in the presence of multiple character strings within the RR. Prior to 4.70,
543 only the first string would be returned. The dnsdb lookup now, by default,
544 preserves the pre-4.70 semantics, but also now takes an extended output
545 separator specification. The separator can be followed by a semicolon, to
546 concatenate the individual text strings together with no join character,
547 or by a comma and a second separator character, in which case the text
548 strings within a TXT record are joined on that second character.
549 Administrators are reminded that DNS provides no ordering guarantees
550 between multiple records in an RRset. For example:
552 foo.example. IN TXT "a" "b" "c"
553 foo.example. IN TXT "d" "e" "f"
555 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
556 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
557 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
563 1. Native DKIM support without an external library.
564 (Note that if no action to prevent it is taken, a straight upgrade will
565 result in DKIM verification of all signed incoming emails. See spec
566 for details on conditionally disabling)
568 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
570 3. There is now a bool{} expansion condition which maps certain strings to
571 true/false condition values (most likely of use in conjunction with the
572 and{} expansion operator).
574 4. The $spam_score, $spam_bar and $spam_report variables are now available
577 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
578 options, provided that Exim is invoked by an admin_user.
580 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
581 which increases compatibility with older clients at the cost of decreased
582 security. Don't set this unless you need to support such clients.
584 7. There is a new expansion operator, ${randint:...} which will produce a
585 "random" number less than the supplied integer. This randomness is
586 not guaranteed to be cryptographically strong, but depending upon how
587 Exim was built may be better than the most naive schemes.
589 8. Exim now explicitly ensures that SHA256 is available when linked against
592 9. The transport_filter_timeout option now applies to SMTP transports too.
598 1. Preliminary DKIM support in Experimental.
604 1. The body_linecount and body_zerocount C variables are now exported in the
607 2. When a dnslists lookup succeeds, the key that was looked up is now placed
608 in $dnslist_matched. When the key is an IP address, it is not reversed in
609 this variable (though it is, of course, in the actual lookup). In simple
612 deny dnslists = spamhaus.example
614 the key is also available in another variable (in this case,
615 $sender_host_address). In more complicated cases, however, this is not
616 true. For example, using a data lookup might generate a dnslists lookup
619 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
621 If this condition succeeds, the value in $dnslist_matched might be
622 192.168.6.7 (for example).
624 3. Authenticators now have a client_condition option. When Exim is running as
625 a client, it skips an authenticator whose client_condition expansion yields
626 "0", "no", or "false". This can be used, for example, to skip plain text
627 authenticators when the connection is not encrypted by a setting such as:
629 client_condition = ${if !eq{$tls_cipher}{}}
631 Note that the 4.67 documentation states that $tls_cipher contains the
632 cipher used for incoming messages. In fact, during SMTP delivery, it
633 contains the cipher used for the delivery. The same is true for
636 4. There is now a -Mvc <message-id> option, which outputs a copy of the
637 message to the standard output, in RFC 2822 format. The option can be used
638 only by an admin user.
640 5. There is now a /noupdate option for the ratelimit ACL condition. It
641 computes the rate and checks the limit as normal, but it does not update
642 the saved data. This means that, in relevant ACLs, it is possible to lookup
643 the existence of a specified (or auto-generated) ratelimit key without
644 incrementing the ratelimit counter for that key.
646 In order for this to be useful, another ACL entry must set the rate
647 for the same key somewhere (otherwise it will always be zero).
652 # Read the rate; if it doesn't exist or is below the maximum
654 deny ratelimit = 100 / 5m / strict / noupdate
655 log_message = RATE: $sender_rate / $sender_rate_period \
656 (max $sender_rate_limit)
658 [... some other logic and tests...]
660 warn ratelimit = 100 / 5m / strict / per_cmd
661 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
662 (max $sender_rate_limit)
663 condition = ${if le{$sender_rate}{$sender_rate_limit}}
667 6. The variable $max_received_linelength contains the number of bytes in the
668 longest line that was received as part of the message, not counting the
669 line termination character(s).
671 7. Host lists can now include +ignore_defer and +include_defer, analagous to
672 +ignore_unknown and +include_unknown. These options should be used with
673 care, probably only in non-critical host lists such as whitelists.
675 8. There's a new option called queue_only_load_latch, which defaults true.
676 If set false when queue_only_load is greater than zero, Exim re-evaluates
677 the load for each incoming message in an SMTP session. Otherwise, once one
678 message is queued, the remainder are also.
680 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
681 cases when an SMTP session ends without sending QUIT. However, when Exim
682 itself is is bad trouble, such as being unable to write to its log files,
683 this ACL is not run, because it might try to do things (such as write to
684 log files) that make the situation even worse.
686 Like the QUIT ACL, this new ACL is provided to make it possible to gather
687 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
688 modifier is forbidden in this ACL.
690 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
691 to a string that indicates the reason for the termination of the SMTP
692 connection. The possible values are:
694 acl-drop Another ACL issued a "drop" command
695 bad-commands Too many unknown or non-mail commands
696 command-timeout Timeout while reading SMTP commands
697 connection-lost The SMTP connection has been lost
698 data-timeout Timeout while reading message data
699 local-scan-error The local_scan() function crashed
700 local-scan-timeout The local_scan() function timed out
701 signal-exit SIGTERM or SIGINT
702 synchronization-error SMTP synchronization error
703 tls-failed TLS failed to start
705 In most cases when an SMTP connection is closed without having received
706 QUIT, Exim sends an SMTP response message before actually closing the
707 connection. With the exception of acl-drop, the default message can be
708 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
709 "drop" verb in another ACL, it is the message from the other ACL that is
712 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
713 servers with individual queries. This is done by starting the query with
714 "servers=x:y:z;", where each item in the list may take one of two forms:
716 (1) If it is just a host name, the appropriate global option (mysql_servers
717 or pgsql_servers) is searched for a host of the same name, and the
718 remaining parameters (database, user, password) are taken from there.
720 (2) If it contains any slashes, it is taken as a complete parameter set.
722 The list of servers is used in exactly the same was as the global list.
723 Once a connection to a server has happened and a query has been
724 successfully executed, processing of the lookup ceases.
726 This feature is intended for use in master/slave situations where updates
727 are occurring, and one wants to update a master rather than a slave. If the
728 masters are in the list for reading, you might have:
730 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
732 In an updating lookup, you could then write
734 ${lookup mysql{servers=master; UPDATE ...}
736 If, on the other hand, the master is not to be used for reading lookups:
738 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
740 you can still update the master by
742 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
744 11. The message_body_newlines option (default FALSE, for backwards
745 compatibility) can be used to control whether newlines are present in
746 $message_body and $message_body_end. If it is FALSE, they are replaced by
753 1. There is a new log selector called smtp_no_mail, which is not included in
754 the default setting. When it is set, a line is written to the main log
755 whenever an accepted SMTP connection terminates without having issued a
758 2. When an item in a dnslists list is followed by = and & and a list of IP
759 addresses, the behaviour was not clear when the lookup returned more than
760 one IP address. This has been solved by the addition of == and =& for "all"
761 rather than the default "any" matching.
763 3. Up till now, the only control over which cipher suites GnuTLS uses has been
764 for the cipher algorithms. New options have been added to allow some of the
765 other parameters to be varied.
767 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
768 set, Exim compiles a runtime option called disable_fsync.
770 5. There is a new variable called $smtp_count_at_connection_start.
772 6. There's a new control called no_pipelining.
774 7. There are two new variables called $sending_ip_address and $sending_port.
775 These are set whenever an SMTP connection to another host has been set up.
777 8. The expansion of the helo_data option in the smtp transport now happens
778 after the connection to the server has been made.
780 9. There is a new expansion operator ${rfc2047d: that decodes strings that
781 are encoded as per RFC 2047.
783 10. There is a new log selector called "pid", which causes the current process
784 id to be added to every log line, in square brackets, immediately after the
787 11. Exim has been modified so that it flushes SMTP output before implementing
788 a delay in an ACL. It also flushes the output before performing a callout,
789 as this can take a substantial time. These behaviours can be disabled by
790 obeying control = no_delay_flush or control = no_callout_flush,
791 respectively, at some earlier stage of the connection.
793 12. There are two new expansion conditions that iterate over a list. They are
794 called forany and forall.
796 13. There's a new global option called dsn_from that can be used to vary the
797 contents of From: lines in bounces and other automatically generated
798 messages ("delivery status notifications" - hence the name of the option).
800 14. The smtp transport has a new option called hosts_avoid_pipelining.
802 15. By default, exigrep does case-insensitive matches. There is now a -I option
803 that makes it case-sensitive.
805 16. A number of new features ("addresses", "map", "filter", and "reduce") have
806 been added to string expansions to make it easier to process lists of
807 items, typically addresses.
809 17. There's a new ACL modifier called "continue". It does nothing of itself,
810 and processing of the ACL always continues with the next condition or
811 modifier. It is provided so that the side effects of expanding its argument
814 18. It is now possible to use newline and other control characters (those with
815 values less than 32, plus DEL) as separators in lists.
817 19. The exigrep utility now has a -v option, which inverts the matching
820 20. The host_find_failed option in the manualroute router can now be set to
827 No new features were added to 4.66.
833 No new features were added to 4.65.
839 1. ACL variables can now be given arbitrary names, as long as they start with
840 "acl_c" or "acl_m" (for connection variables and message variables), are at
841 least six characters long, with the sixth character being either a digit or
844 2. There is a new ACL modifier called log_reject_target. It makes it possible
845 to specify which logs are used for messages about ACL rejections.
847 3. There is a new authenticator called "dovecot". This is an interface to the
848 authentication facility of the Dovecot POP/IMAP server, which can support a
849 number of authentication methods.
851 4. The variable $message_headers_raw provides a concatenation of all the
852 messages's headers without any decoding. This is in contrast to
853 $message_headers, which does RFC2047 decoding on the header contents.
855 5. In a DNS black list, if two domain names, comma-separated, are given, the
856 second is used first to do an initial check, making use of any IP value
857 restrictions that are set. If there is a match, the first domain is used,
858 without any IP value restrictions, to get the TXT record.
860 6. All authenticators now have a server_condition option.
862 7. There is a new command-line option called -Mset. It is useful only in
863 conjunction with -be (that is, when testing string expansions). It must be
864 followed by a message id; Exim loads the given message from its spool
865 before doing the expansions.
867 8. Another similar new command-line option is called -bem. It operates like
868 -be except that it must be followed by the name of a file that contains a
871 9. When an address is delayed because of a 4xx response to a RCPT command, it
872 is now the combination of sender and recipient that is delayed in
873 subsequent queue runs until its retry time is reached.
875 10. Unary negation and the bitwise logical operators and, or, xor, not, and
876 shift, have been added to the eval: and eval10: expansion items.
878 11. The variables $interface_address and $interface_port have been renamed
879 as $received_ip_address and $received_port, to make it clear that they
880 relate to message reception rather than delivery. (The old names remain
881 available for compatibility.)
883 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
884 to vary the message that is sent when an SMTP command is accepted.
890 1. There is a new Boolean option called filter_prepend_home for the redirect
893 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
894 start of receiving a non-SMTP message, before any of the message has been
897 3. When an SMTP error message is specified in a "message" modifier in an ACL,
898 or in a :fail: or :defer: message in a redirect router, Exim now checks the
899 start of the message for an SMTP error code.
901 4. There is a new parameter for LDAP lookups called "referrals", which takes
902 one of the settings "follow" (the default) or "nofollow".
904 5. Version 20070721.2 of exipick now included, offering these new options:
906 After all other sorting options have bee processed, reverse order
907 before displaying messages (-R is synonym).
909 Randomize order of matching messages before displaying.
911 Instead of displaying the matching messages, display the sum
913 --sort <variable>[,<variable>...]
914 Before displaying matching messages, sort the messages according to
915 each messages value for each variable.
917 Negate the value for every test (returns inverse output from the
918 same criteria without --not).
924 1. The ${readsocket expansion item now supports Internet domain sockets as well
925 as Unix domain sockets. If the first argument begins "inet:", it must be of
926 the form "inet:host:port". The port is mandatory; it may be a number or the
927 name of a TCP port in /etc/services. The host may be a name, or it may be an
928 IP address. An ip address may optionally be enclosed in square brackets.
929 This is best for IPv6 addresses. For example:
931 ${readsocket{inet:[::1]:1234}{<request data>}...
933 Only a single host name may be given, but if looking it up yield more than
934 one IP address, they are each tried in turn until a connection is made. Once
935 a connection has been made, the behaviour is as for ${readsocket with a Unix
938 2. If a redirect router sets up file or pipe deliveries for more than one
939 incoming address, and the relevant transport has batch_max set greater than
940 one, a batch delivery now occurs.
942 3. The appendfile transport has a new option called maildirfolder_create_regex.
943 Its value is a regular expression. For a maildir delivery, this is matched
944 against the maildir directory; if it matches, Exim ensures that a
945 maildirfolder file is created alongside the new, cur, and tmp directories.
951 The documentation is up-to-date for the 4.61 release. Major new features since
952 the 4.60 release are:
954 . An option called disable_ipv6, to disable the use of IPv6 completely.
956 . An increase in the number of ACL variables to 20 of each type.
958 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
959 $2, $3, (though those are still set) because the numeric variables get used
960 for other things in complicated expansions.
962 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
964 . It is possible to use setclassresources() on some BSD OS to control the
965 resources used in pipe deliveries.
967 . A new ACL modifier called add_header, which can be used with any verb.
969 . More errors are detectable in retry rules.
971 There are a number of other additions too.
977 The documentation is up-to-date for the 4.60 release. Major new features since
978 the 4.50 release are:
980 . Support for SQLite.
982 . Support for IGNOREQUOTA in LMTP.
984 . Extensions to the "submission mode" features.
986 . Support for Client SMTP Authorization (CSA).
988 . Support for ratelimiting hosts and users.
990 . New expansion items to help with the BATV "prvs" scheme.
992 . A "match_ip" condition, that matches an IP address against a list.
994 There are many more minor changes.
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