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.
36 1. If built with the EXPERIMENTAL_PROXY feature enabled, Exim can be
37 configured to expect an initial header from a proxy that will make the
38 actual external source IP:host be used in exim instead of the IP of the
39 proxy that is connecting to it.
41 2. New verify option header_names_ascii, which will check to make sure
42 there are no non-ASCII characters in header names. Exim itself handles
43 those non-ASCII characters, but downstream apps may not, so Exim can
44 detect and reject if those characters are present.
46 3. New expansion operator ${utf8clean:string} to replace malformed UTF8
47 codepoints with valid ones.
49 4. New malware type "sock". Talks over a Unix or TCP socket, sending one
50 command line and matching a regex against the return data for trigger
51 and a second regex to extract malware_name. The mail spoolfile name can
52 be included in the command line.
54 5. The smtp transport now supports options "tls_verify_hosts" and
55 "tls_try_verify_hosts". If either is set the certificate verification
56 is split from the encryption operation. The default remains that a failed
57 verification cancels the encryption.
59 6. New SERVERS override of default ldap server list. In the ACLs, an ldap
60 lookup can now set a list of servers to use that is different from the
63 7. New command-line option -C for exiqgrep to specify alternate exim.conf
64 file when searching the queue.
66 8. OCSP now supports GnuTLS also, if you have version 3.1.3 or later of that.
68 9. Support for DNSSEC on outbound connections.
70 10. New variables "tls_(in,out)_(our,peer)cert" and expansion item
71 "certextract" to extract fields from them. Hash operators md5 and sha1
72 work over them for generating fingerprints, and a new sha256 operator
75 11. PRDR is now supported dy default.
77 12. OCSP stapling is now supported by default.
79 13. If built with the EXPERIMENTAL_DSN feature enabled, Exim will output
80 Delivery Status Notification messages in MIME format, and negociate
81 DSN features per RFC 3461.
87 1. New command-line option -bI:sieve will list all supported sieve extensions
88 of this Exim build on standard output, one per line.
89 ManageSieve (RFC 5804) providers managing scripts for use by Exim should
90 query this to establish the correct list to include in the protocol's
91 SIEVE capability line.
93 2. If the -n option is combined with the -bP option, then the name of an
94 emitted option is not output, only the value (if visible to you).
95 For instance, "exim -n -bP pid_file_path" should just emit a pathname
96 followed by a newline, and no other text.
98 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
99 has a "tls_dh_min_bits" option, to set the minimum acceptable number of
100 bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
101 acceptable for security. (Option accepted but ignored if using OpenSSL).
102 Defaults to 1024, the old value. May be lowered only to 512, or raised as
103 far as you like. Raising this may hinder TLS interoperability with other
104 sites and is not currently recommended. Lowering this will permit you to
105 establish a TLS session which is not as secure as you might like.
107 Unless you really know what you are doing, leave it alone.
109 4. If not built with DISABLE_DNSSEC, Exim now has the main option
110 dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
111 to send the DO flag to your recursive resolver. If you have a recursive
112 resolver, which can set the Authenticated Data (AD) flag in results, Exim
113 can now detect this. Exim does not perform validation itself, instead
114 relying upon a trusted path to the resolver.
116 Current status: work-in-progress; $sender_host_dnssec variable added.
118 5. DSCP support for outbound connections: on a transport using the smtp driver,
119 set "dscp = ef", for instance, to cause the connections to have the relevant
120 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
122 Similarly for inbound connections, there is a new control modifier, dscp,
123 so "warn control = dscp/ef" in the connect ACL, or after authentication.
125 Supported values depend upon system libraries. "exim -bI:dscp" to list the
126 ones Exim knows of. You can also set a raw number 0..0x3F.
128 6. The -G command-line flag is no longer ignored; it is now equivalent to an
129 ACL setting "control = suppress_local_fixups". The -L command-line flag
130 is now accepted and forces use of syslog, with the provided tag as the
131 process name. A few other flags used by Sendmail are now accepted and
134 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
135 ACL modifier; works for single-recipient mails which are recieved on and
136 deliverable via SMTP. Using the connection made for a recipient verify,
137 if requested before the verify, or a new one made for the purpose while
138 the inbound connection is still active. The bulk of the mail item is copied
139 direct from the inbound socket to the outbound (as well as the spool file).
140 When the source notifies the end of data, the data acceptance by the destination
141 is negociated before the acceptance is sent to the source. If the destination
142 does not accept the mail item, for example due to content-scanning, the item
143 is not accepted from the source and therefore there is no need to generate
144 a bounce mail. This is of benefit when providing a secondary-MX service.
145 The downside is that delays are under the control of the ultimate destination
148 The Recieved-by: header on items delivered by cutthrough is generated
149 early in reception rather than at the end; this will affect any timestamp
150 included. The log line showing delivery is recorded before that showing
151 reception; it uses a new ">>" tag instead of "=>".
153 To support the feature, verify-callout connections can now use ESMTP and TLS.
154 The usual smtp transport options are honoured, plus a (new, default everything)
155 hosts_verify_avoid_tls.
157 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
158 for specific access to the information for each connection. The old names
159 are present for now but deprecated.
161 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING.
163 8. New expansion operators ${listnamed:name} to get the content of a named list
164 and ${listcount:string} to count the items in a list.
166 9. New global option "gnutls_allow_auto_pkcs11", defaults false. The GnuTLS
167 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
168 modules. For some situations this is desirable, but we expect admin in
169 those situations to know they want the feature. More commonly, it means
170 that GUI user modules get loaded and are broken by the setuid Exim being
171 unable to access files specified in environment variables and passed
172 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
173 unless this new option is set.
175 Some older OS's with earlier versions of GnuTLS might not have pkcs11 ability,
176 so have also added a build option which can be used to build Exim with GnuTLS
177 but without trying to use any kind of PKCS11 support. Uncomment this in the
180 AVOID_GNUTLS_PKCS11=yes
182 10. The "acl = name" condition on an ACL now supports optional arguments.
183 New expansion item "${acl {name}{arg}...}" and expansion condition
184 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
185 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
186 Variable $acl_narg contains the number of arguments. If the ACL sets
187 a "message =" value this becomes the result of the expansion item,
188 or the value of $value for the expansion condition. If the ACL returns
189 accept the expansion condition is true; if reject, false. A defer
190 return results in a forced fail.
192 11. Routers and transports can now have multiple headers_add and headers_remove
193 option lines. The concatenated list is used.
195 12. New ACL modifier "remove_header" can remove headers before message gets
196 handled by routers/transports.
198 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
199 "aaaa" and "a" lookups is done and the full set of results returned.
201 14. New expansion variable $headers_added with content from ACL add_header
202 modifier (but not yet added to messsage).
204 15. New 8bitmime status logging option for received messages. Log field "M8S".
206 16. New authenticated_sender logging option, adding to log field "A".
208 17. New expansion variables $router_name and $transport_name. Useful
209 particularly for debug_print as -bt commandline option does not
210 require privilege whereas -d does.
212 18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
213 proposed extension to SMTP from Eric Hall.
215 19. The pipe transport has gained the force_command option, to allow
216 decorating commands from user .forward pipe aliases with prefix
217 wrappers, for instance.
219 20. Callout connections can now AUTH; the same controls as normal delivery
222 21. Support for DMARC, using opendmarc libs, can be enabled. It adds new
223 options: dmarc_forensic_sender, dmarc_history_file, and dmarc_tld_file.
224 It adds new expansion variables $dmarc_ar_header, $dmarc_status,
225 $dmarc_status_text, and $dmarc_used_domain. It adds a new acl modifier
226 dmarc_status. It adds new control flags dmarc_disable_verify and
227 dmarc_enable_forensic.
229 22. Add expansion variable $authenticated_fail_id, which is the username
230 provided to the authentication method which failed. It is available
231 for use in subsequent ACL processing (typically quit or notquit ACLs).
233 23. New ACL modifer "udpsend" can construct a UDP packet to send to a given
236 24. New ${hexquote:..string..} expansion operator converts non-printable
237 characters in the string to \xNN form.
239 25. Experimental TPDA (Transport Post Delivery Action) function added.
240 Patch provided by Axel Rau.
242 26. Experimental Redis lookup added. Patch provided by Warren Baker.
248 1. New authenticator driver, "gsasl". Server-only (at present).
249 This is a SASL interface, licensed under GPL, which can be found at
250 http://www.gnu.org/software/gsasl/.
251 This system does not provide sources of data for authentication, so
252 careful use needs to be made of the conditions in Exim.
254 2. New authenticator driver, "heimdal_gssapi". Server-only.
255 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
256 is no longer honoured for setuid programs by Heimdal. Use the
257 "server_keytab" option to point to the keytab.
259 3. The "pkg-config" system can now be used when building Exim to reference
260 cflags and library information for lookups and authenticators, rather
261 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
262 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
263 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
265 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
266 find the headers and libraries for PCRE.
268 4. New expansion variable $tls_bits.
270 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
271 be joined together with ASCII NUL characters to construct the key to pass
272 into the DBM library. Can be used with gsasl to access sasldb2 files as
275 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
277 Avoid release 1.0.1a if you can. Note that the default value of
278 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
279 increased susceptibility to attack. This may still have interoperability
280 implications for very old clients (see version 4.31 change 37) but
281 administrators can choose to make the trade-off themselves and restore
282 compatibility at the cost of session security.
284 7. Use of the new expansion variable $tls_sni in the main configuration option
285 tls_certificate will cause Exim to re-expand the option, if the client
286 sends the TLS Server Name Indication extension, to permit choosing a
287 different certificate; tls_privatekey will also be re-expanded. You must
288 still set these options to expand to valid files when $tls_sni is not set.
290 The SMTP Transport has gained the option tls_sni, which will set a hostname
291 for outbound TLS sessions, and set $tls_sni too.
293 A new log_selector, +tls_sni, has been added, to log received SNI values
294 for Exim as a server.
296 8. The existing "accept_8bitmime" option now defaults to true. This means
297 that Exim is deliberately not strictly RFC compliant. We're following
298 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
299 Those who disagree, or know that they are talking to mail servers that,
300 even today, are not 8-bit clean, need to turn off this option.
302 9. Exim can now be started with -bw (with an optional timeout, given as
303 -bw<timespec>). With this, stdin at startup is a socket that is
304 already listening for connections. This has a more modern name of
305 "socket activation", but forcing the activated socket to fd 0. We're
306 interested in adding more support for modern variants.
308 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
309 for numbers indicates multiplication by 1024^3.
311 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
312 gnutls_require_mac & gnutls_require_protocols are no longer supported.
313 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
314 string, documentation for which is at:
315 http://www.gnutls.org/manual/html_node/Priority-Strings.html
317 SNI support has been added to Exim's GnuTLS integration too.
319 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
320 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
322 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
323 is now available. If the contents of the file are valid, then Exim will
324 send that back in response to a TLS status request; this is OCSP Stapling.
325 Exim will not maintain the contents of the file in any way: administrators
326 are responsible for ensuring that it is up-to-date.
328 See "experimental-spec.txt" for more details.
330 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
331 identically to TXT record lookups.
333 14. New expansion variable $tod_epoch_l for higher-precision time.
335 15. New global option tls_dh_max_bits, defaulting to current value of NSS
336 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
337 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
339 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
340 Option can now be a path or an identifier for a standard prime.
341 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
342 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
345 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
346 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
347 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
353 1. New options for the ratelimit ACL condition: /count= and /unique=.
354 The /noupdate option has been replaced by a /readonly option.
356 2. The SMTP transport's protocol option may now be set to "smtps", to
357 use SSL-on-connect outbound.
359 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
360 there is a problem talking to the AV scanner, or the AV scanner running.
362 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
363 and check if the search item is a member of the list. This does not
364 support named lists, but does subject the list part to string expansion.
366 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
367 built, Exim no longer performs string expansion on the second string of
368 the match_* expansion conditions: "match_address", "match_domain",
369 "match_ip" & "match_local_part". Named lists can still be used.
375 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
376 or off in the resolver library.
382 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
383 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
384 libraries. The following global options have been added in support of
385 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
386 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
388 2. The pipe transport now takes a boolean option, "freeze_signal", default
389 false. When true, if the external delivery command exits on a signal then
390 Exim will freeze the message in the queue, instead of generating a bounce.
392 3. Log filenames may now use %M as an escape, instead of %D (still available).
393 The %M pattern expands to yyyymm, providing month-level resolution.
395 4. The $message_linecount variable is now updated for the maildir_tag option,
396 in the same way as $message_size, to reflect the real number of lines,
397 including any header additions or removals from transport.
399 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
400 Exim now selects entries randomly, to better scale in a cluster setup.
406 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
407 the flaw permitted the Exim run-time user to cause root to append to
408 arbitrary files of the attacker's choosing, with the content based
409 on content supplied by the attacker.
411 2. Exim now supports loading some lookup types at run-time, using your
412 platform's dlopen() functionality. This has limited platform support
413 and the intention is not to support every variant, it's limited to
414 dlopen(). This permits the main Exim binary to not be linked against
415 all the libraries needed for all the lookup types.
421 NOTE: this version is not guaranteed backwards-compatible, please read the
422 items below carefully
424 1. A new main configuration option, "openssl_options", is available if Exim
425 is built with SSL support provided by OpenSSL. The option allows
426 administrators to specify OpenSSL options to be used on connections;
427 typically this is to set bug compatibility features which the OpenSSL
428 developers have not enabled by default. There may be security
429 consequences for certain options, so these should not be changed
432 2. A new pipe transport option, "permit_coredumps", may help with problem
433 diagnosis in some scenarios. Note that Exim is typically installed as
434 a setuid binary, which on most OSes will inhibit coredumps by default,
435 so that safety mechanism would have to be overridden for this option to
436 be able to take effect.
438 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
439 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
440 Note that this switches Exim to use a new API ("INSTREAM") and a future
441 release of ClamAV will remove support for the old API ("STREAM").
443 The av_scanner option, when set to "clamd", now takes an optional third
444 part, "local", which causes Exim to pass a filename to ClamAV instead of
445 the file content. This is the same behaviour as when clamd is pointed at
446 a Unix-domain socket. For example:
448 av_scanner = clamd:192.0.2.3 1234:local
450 ClamAV's ExtendedDetectionInfo response format is now handled.
452 4. There is now a -bmalware option, restricted to admin users. This option
453 takes one parameter, a filename, and scans that file with Exim's
454 malware-scanning framework. This is intended purely as a debugging aid
455 to ensure that Exim's scanning is working, not to replace other tools.
456 Note that the ACL framework is not invoked, so if av_scanner references
457 ACL variables without a fallback then this will fail.
459 5. There is a new expansion operator, "reverse_ip", which will reverse IP
460 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
462 ${reverse_ip:192.0.2.4}
464 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
465 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
467 6. There is a new ACL control called "debug", to enable debug logging.
468 This allows selective logging of certain incoming transactions within
469 production environments, with some care. It takes two options, "tag"
470 and "opts"; "tag" is included in the filename of the log and "opts"
471 is used as per the -d<options> command-line option. Examples, which
472 don't all make sense in all contexts:
475 control = debug/tag=.$sender_host_address
476 control = debug/opts=+expand+acl
477 control = debug/tag=.$message_exim_id/opts=+expand
479 7. It has always been implicit in the design and the documentation that
480 "the Exim user" is not root. src/EDITME said that using root was
481 "very strongly discouraged". This is not enough to keep people from
482 shooting themselves in the foot in days when many don't configure Exim
483 themselves but via package build managers. The security consequences of
484 running various bits of network code are severe if there should be bugs in
485 them. As such, the Exim user may no longer be root. If configured
486 statically, Exim will refuse to build. If configured as ref:user then Exim
487 will exit shortly after start-up. If you must shoot yourself in the foot,
488 then henceforth you will have to maintain your own local patches to strip
491 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
492 condition logic to determine truth/failure and will fail to expand many
493 strings, bool_lax{} uses the router condition logic, where most strings
495 Note: bool{00} is false, bool_lax{00} is true.
497 9. Routers now support multiple "condition" tests.
499 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
500 Setting this allows an admin to define which entry in the tcpwrappers
501 config file will be used to control access to the daemon. This option
502 is only available when Exim is built with USE_TCP_WRAPPERS. The
503 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
506 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
507 the Exim run-time user, instead of root.
509 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
510 is forced on. This is mitigated by the new build option
511 TRUSTED_CONFIG_LIST which defines a list of configuration files which
512 are trusted; one per line. If a config file is owned by root and matches
513 a pathname in the list, then it may be invoked by the Exim build-time
514 user without Exim relinquishing root privileges.
516 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
517 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
518 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
519 include the main config. As a transition mechanism, we are temporarily
520 providing a work-around: the new build option WHITELIST_D_MACROS provides
521 a colon-separated list of macro names which may be overridden by the Exim
522 run-time user. The values of these macros are constrained to the regex
523 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
529 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
530 writable, the other to locking of MBX folders (not mbox).
532 2. MySQL stored procedures are now supported.
534 3. The dkim_domain transport option is now a list, not a single string, and
535 messages will be signed for each element in the list (discarding
538 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
539 in the presence of multiple character strings within the RR. Prior to 4.70,
540 only the first string would be returned. The dnsdb lookup now, by default,
541 preserves the pre-4.70 semantics, but also now takes an extended output
542 separator specification. The separator can be followed by a semicolon, to
543 concatenate the individual text strings together with no join character,
544 or by a comma and a second separator character, in which case the text
545 strings within a TXT record are joined on that second character.
546 Administrators are reminded that DNS provides no ordering guarantees
547 between multiple records in an RRset. For example:
549 foo.example. IN TXT "a" "b" "c"
550 foo.example. IN TXT "d" "e" "f"
552 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
553 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
554 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
560 1. Native DKIM support without an external library.
561 (Note that if no action to prevent it is taken, a straight upgrade will
562 result in DKIM verification of all signed incoming emails. See spec
563 for details on conditionally disabling)
565 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
567 3. There is now a bool{} expansion condition which maps certain strings to
568 true/false condition values (most likely of use in conjunction with the
569 and{} expansion operator).
571 4. The $spam_score, $spam_bar and $spam_report variables are now available
574 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
575 options, provided that Exim is invoked by an admin_user.
577 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
578 which increases compatibility with older clients at the cost of decreased
579 security. Don't set this unless you need to support such clients.
581 7. There is a new expansion operator, ${randint:...} which will produce a
582 "random" number less than the supplied integer. This randomness is
583 not guaranteed to be cryptographically strong, but depending upon how
584 Exim was built may be better than the most naive schemes.
586 8. Exim now explicitly ensures that SHA256 is available when linked against
589 9. The transport_filter_timeout option now applies to SMTP transports too.
595 1. Preliminary DKIM support in Experimental.
601 1. The body_linecount and body_zerocount C variables are now exported in the
604 2. When a dnslists lookup succeeds, the key that was looked up is now placed
605 in $dnslist_matched. When the key is an IP address, it is not reversed in
606 this variable (though it is, of course, in the actual lookup). In simple
609 deny dnslists = spamhaus.example
611 the key is also available in another variable (in this case,
612 $sender_host_address). In more complicated cases, however, this is not
613 true. For example, using a data lookup might generate a dnslists lookup
616 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
618 If this condition succeeds, the value in $dnslist_matched might be
619 192.168.6.7 (for example).
621 3. Authenticators now have a client_condition option. When Exim is running as
622 a client, it skips an authenticator whose client_condition expansion yields
623 "0", "no", or "false". This can be used, for example, to skip plain text
624 authenticators when the connection is not encrypted by a setting such as:
626 client_condition = ${if !eq{$tls_cipher}{}}
628 Note that the 4.67 documentation states that $tls_cipher contains the
629 cipher used for incoming messages. In fact, during SMTP delivery, it
630 contains the cipher used for the delivery. The same is true for
633 4. There is now a -Mvc <message-id> option, which outputs a copy of the
634 message to the standard output, in RFC 2822 format. The option can be used
635 only by an admin user.
637 5. There is now a /noupdate option for the ratelimit ACL condition. It
638 computes the rate and checks the limit as normal, but it does not update
639 the saved data. This means that, in relevant ACLs, it is possible to lookup
640 the existence of a specified (or auto-generated) ratelimit key without
641 incrementing the ratelimit counter for that key.
643 In order for this to be useful, another ACL entry must set the rate
644 for the same key somewhere (otherwise it will always be zero).
649 # Read the rate; if it doesn't exist or is below the maximum
651 deny ratelimit = 100 / 5m / strict / noupdate
652 log_message = RATE: $sender_rate / $sender_rate_period \
653 (max $sender_rate_limit)
655 [... some other logic and tests...]
657 warn ratelimit = 100 / 5m / strict / per_cmd
658 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
659 (max $sender_rate_limit)
660 condition = ${if le{$sender_rate}{$sender_rate_limit}}
664 6. The variable $max_received_linelength contains the number of bytes in the
665 longest line that was received as part of the message, not counting the
666 line termination character(s).
668 7. Host lists can now include +ignore_defer and +include_defer, analagous to
669 +ignore_unknown and +include_unknown. These options should be used with
670 care, probably only in non-critical host lists such as whitelists.
672 8. There's a new option called queue_only_load_latch, which defaults true.
673 If set false when queue_only_load is greater than zero, Exim re-evaluates
674 the load for each incoming message in an SMTP session. Otherwise, once one
675 message is queued, the remainder are also.
677 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
678 cases when an SMTP session ends without sending QUIT. However, when Exim
679 itself is is bad trouble, such as being unable to write to its log files,
680 this ACL is not run, because it might try to do things (such as write to
681 log files) that make the situation even worse.
683 Like the QUIT ACL, this new ACL is provided to make it possible to gather
684 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
685 modifier is forbidden in this ACL.
687 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
688 to a string that indicates the reason for the termination of the SMTP
689 connection. The possible values are:
691 acl-drop Another ACL issued a "drop" command
692 bad-commands Too many unknown or non-mail commands
693 command-timeout Timeout while reading SMTP commands
694 connection-lost The SMTP connection has been lost
695 data-timeout Timeout while reading message data
696 local-scan-error The local_scan() function crashed
697 local-scan-timeout The local_scan() function timed out
698 signal-exit SIGTERM or SIGINT
699 synchronization-error SMTP synchronization error
700 tls-failed TLS failed to start
702 In most cases when an SMTP connection is closed without having received
703 QUIT, Exim sends an SMTP response message before actually closing the
704 connection. With the exception of acl-drop, the default message can be
705 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
706 "drop" verb in another ACL, it is the message from the other ACL that is
709 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
710 servers with individual queries. This is done by starting the query with
711 "servers=x:y:z;", where each item in the list may take one of two forms:
713 (1) If it is just a host name, the appropriate global option (mysql_servers
714 or pgsql_servers) is searched for a host of the same name, and the
715 remaining parameters (database, user, password) are taken from there.
717 (2) If it contains any slashes, it is taken as a complete parameter set.
719 The list of servers is used in exactly the same was as the global list.
720 Once a connection to a server has happened and a query has been
721 successfully executed, processing of the lookup ceases.
723 This feature is intended for use in master/slave situations where updates
724 are occurring, and one wants to update a master rather than a slave. If the
725 masters are in the list for reading, you might have:
727 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
729 In an updating lookup, you could then write
731 ${lookup mysql{servers=master; UPDATE ...}
733 If, on the other hand, the master is not to be used for reading lookups:
735 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
737 you can still update the master by
739 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
741 11. The message_body_newlines option (default FALSE, for backwards
742 compatibility) can be used to control whether newlines are present in
743 $message_body and $message_body_end. If it is FALSE, they are replaced by
750 1. There is a new log selector called smtp_no_mail, which is not included in
751 the default setting. When it is set, a line is written to the main log
752 whenever an accepted SMTP connection terminates without having issued a
755 2. When an item in a dnslists list is followed by = and & and a list of IP
756 addresses, the behaviour was not clear when the lookup returned more than
757 one IP address. This has been solved by the addition of == and =& for "all"
758 rather than the default "any" matching.
760 3. Up till now, the only control over which cipher suites GnuTLS uses has been
761 for the cipher algorithms. New options have been added to allow some of the
762 other parameters to be varied.
764 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
765 set, Exim compiles a runtime option called disable_fsync.
767 5. There is a new variable called $smtp_count_at_connection_start.
769 6. There's a new control called no_pipelining.
771 7. There are two new variables called $sending_ip_address and $sending_port.
772 These are set whenever an SMTP connection to another host has been set up.
774 8. The expansion of the helo_data option in the smtp transport now happens
775 after the connection to the server has been made.
777 9. There is a new expansion operator ${rfc2047d: that decodes strings that
778 are encoded as per RFC 2047.
780 10. There is a new log selector called "pid", which causes the current process
781 id to be added to every log line, in square brackets, immediately after the
784 11. Exim has been modified so that it flushes SMTP output before implementing
785 a delay in an ACL. It also flushes the output before performing a callout,
786 as this can take a substantial time. These behaviours can be disabled by
787 obeying control = no_delay_flush or control = no_callout_flush,
788 respectively, at some earlier stage of the connection.
790 12. There are two new expansion conditions that iterate over a list. They are
791 called forany and forall.
793 13. There's a new global option called dsn_from that can be used to vary the
794 contents of From: lines in bounces and other automatically generated
795 messages ("delivery status notifications" - hence the name of the option).
797 14. The smtp transport has a new option called hosts_avoid_pipelining.
799 15. By default, exigrep does case-insensitive matches. There is now a -I option
800 that makes it case-sensitive.
802 16. A number of new features ("addresses", "map", "filter", and "reduce") have
803 been added to string expansions to make it easier to process lists of
804 items, typically addresses.
806 17. There's a new ACL modifier called "continue". It does nothing of itself,
807 and processing of the ACL always continues with the next condition or
808 modifier. It is provided so that the side effects of expanding its argument
811 18. It is now possible to use newline and other control characters (those with
812 values less than 32, plus DEL) as separators in lists.
814 19. The exigrep utility now has a -v option, which inverts the matching
817 20. The host_find_failed option in the manualroute router can now be set to
824 No new features were added to 4.66.
830 No new features were added to 4.65.
836 1. ACL variables can now be given arbitrary names, as long as they start with
837 "acl_c" or "acl_m" (for connection variables and message variables), are at
838 least six characters long, with the sixth character being either a digit or
841 2. There is a new ACL modifier called log_reject_target. It makes it possible
842 to specify which logs are used for messages about ACL rejections.
844 3. There is a new authenticator called "dovecot". This is an interface to the
845 authentication facility of the Dovecot POP/IMAP server, which can support a
846 number of authentication methods.
848 4. The variable $message_headers_raw provides a concatenation of all the
849 messages's headers without any decoding. This is in contrast to
850 $message_headers, which does RFC2047 decoding on the header contents.
852 5. In a DNS black list, if two domain names, comma-separated, are given, the
853 second is used first to do an initial check, making use of any IP value
854 restrictions that are set. If there is a match, the first domain is used,
855 without any IP value restrictions, to get the TXT record.
857 6. All authenticators now have a server_condition option.
859 7. There is a new command-line option called -Mset. It is useful only in
860 conjunction with -be (that is, when testing string expansions). It must be
861 followed by a message id; Exim loads the given message from its spool
862 before doing the expansions.
864 8. Another similar new command-line option is called -bem. It operates like
865 -be except that it must be followed by the name of a file that contains a
868 9. When an address is delayed because of a 4xx response to a RCPT command, it
869 is now the combination of sender and recipient that is delayed in
870 subsequent queue runs until its retry time is reached.
872 10. Unary negation and the bitwise logical operators and, or, xor, not, and
873 shift, have been added to the eval: and eval10: expansion items.
875 11. The variables $interface_address and $interface_port have been renamed
876 as $received_ip_address and $received_port, to make it clear that they
877 relate to message reception rather than delivery. (The old names remain
878 available for compatibility.)
880 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
881 to vary the message that is sent when an SMTP command is accepted.
887 1. There is a new Boolean option called filter_prepend_home for the redirect
890 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
891 start of receiving a non-SMTP message, before any of the message has been
894 3. When an SMTP error message is specified in a "message" modifier in an ACL,
895 or in a :fail: or :defer: message in a redirect router, Exim now checks the
896 start of the message for an SMTP error code.
898 4. There is a new parameter for LDAP lookups called "referrals", which takes
899 one of the settings "follow" (the default) or "nofollow".
901 5. Version 20070721.2 of exipick now included, offering these new options:
903 After all other sorting options have bee processed, reverse order
904 before displaying messages (-R is synonym).
906 Randomize order of matching messages before displaying.
908 Instead of displaying the matching messages, display the sum
910 --sort <variable>[,<variable>...]
911 Before displaying matching messages, sort the messages according to
912 each messages value for each variable.
914 Negate the value for every test (returns inverse output from the
915 same criteria without --not).
921 1. The ${readsocket expansion item now supports Internet domain sockets as well
922 as Unix domain sockets. If the first argument begins "inet:", it must be of
923 the form "inet:host:port". The port is mandatory; it may be a number or the
924 name of a TCP port in /etc/services. The host may be a name, or it may be an
925 IP address. An ip address may optionally be enclosed in square brackets.
926 This is best for IPv6 addresses. For example:
928 ${readsocket{inet:[::1]:1234}{<request data>}...
930 Only a single host name may be given, but if looking it up yield more than
931 one IP address, they are each tried in turn until a connection is made. Once
932 a connection has been made, the behaviour is as for ${readsocket with a Unix
935 2. If a redirect router sets up file or pipe deliveries for more than one
936 incoming address, and the relevant transport has batch_max set greater than
937 one, a batch delivery now occurs.
939 3. The appendfile transport has a new option called maildirfolder_create_regex.
940 Its value is a regular expression. For a maildir delivery, this is matched
941 against the maildir directory; if it matches, Exim ensures that a
942 maildirfolder file is created alongside the new, cur, and tmp directories.
948 The documentation is up-to-date for the 4.61 release. Major new features since
949 the 4.60 release are:
951 . An option called disable_ipv6, to disable the use of IPv6 completely.
953 . An increase in the number of ACL variables to 20 of each type.
955 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
956 $2, $3, (though those are still set) because the numeric variables get used
957 for other things in complicated expansions.
959 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
961 . It is possible to use setclassresources() on some BSD OS to control the
962 resources used in pipe deliveries.
964 . A new ACL modifier called add_header, which can be used with any verb.
966 . More errors are detectable in retry rules.
968 There are a number of other additions too.
974 The documentation is up-to-date for the 4.60 release. Major new features since
975 the 4.50 release are:
977 . Support for SQLite.
979 . Support for IGNOREQUOTA in LMTP.
981 . Extensions to the "submission mode" features.
983 . Support for Client SMTP Authorization (CSA).
985 . Support for ratelimiting hosts and users.
987 . New expansion items to help with the BATV "prvs" scheme.
989 . A "match_ip" condition, that matches an IP address against a list.
991 There are many more minor changes.
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