95b4119d167c853800511cbec885af1ec755eb9b
[exim.git] / doc / doc-txt / NewStuff
1 New Features in Exim
2 --------------------
3
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.
8
9 Version 4.83
10 ------------
11
12 1. If built with the EXPERIMENTAL_PROXY feature enabled, Exim can be
13 configured to expect an initial header from a proxy that will make the
14 actual external source IP:host be used in exim instead of the IP of the
15 proxy that is connecting to it.
16
17 2. New verify option header_names_ascii, which will check to make sure
18 there are no non-ASCII characters in header names. Exim itself handles
19 those non-ASCII characters, but downstream apps may not, so Exim can
20 detect and reject if those characters are present.
21
22 3. New expansion operator ${utf8clean:string} to replace malformed UTF8
23 codepoints with valid ones.
24
25 4. New malware type "sock". Talks over a Unix or TCP socket, sending one
26 command line and matching a regex against the return data for trigger
27 and a second regex to extract malware_name. The mail spoofile name can
28 be included in the command line.
29
30 5. When built with OpenSSL the smtp transport now supports options
31 "tls_verify_hosts" and "tls_try_verify_hosts". If either is set the
32 certificate verification is split from the encryption operation. The
33 default remains that a failed verification cancels the encryption.
34
35
36 Version 4.82
37 ------------
38
39 1. New command-line option -bI:sieve will list all supported sieve extensions
40 of this Exim build on standard output, one per line.
41 ManageSieve (RFC 5804) providers managing scripts for use by Exim should
42 query this to establish the correct list to include in the protocol's
43 SIEVE capability line.
44
45 2. If the -n option is combined with the -bP option, then the name of an
46 emitted option is not output, only the value (if visible to you).
47 For instance, "exim -n -bP pid_file_path" should just emit a pathname
48 followed by a newline, and no other text.
49
50 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
51 has a "tls_dh_min_bits" option, to set the minimum acceptable number of
52 bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
53 acceptable for security. (Option accepted but ignored if using OpenSSL).
54 Defaults to 1024, the old value. May be lowered only to 512, or raised as
55 far as you like. Raising this may hinder TLS interoperability with other
56 sites and is not currently recommended. Lowering this will permit you to
57 establish a TLS session which is not as secure as you might like.
58
59 Unless you really know what you are doing, leave it alone.
60
61 4. If not built with DISABLE_DNSSEC, Exim now has the main option
62 dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
63 to send the DO flag to your recursive resolver. If you have a recursive
64 resolver, which can set the Authenticated Data (AD) flag in results, Exim
65 can now detect this. Exim does not perform validation itself, instead
66 relying upon a trusted path to the resolver.
67
68 Current status: work-in-progress; $sender_host_dnssec variable added.
69
70 5. DSCP support for outbound connections: on a transport using the smtp driver,
71 set "dscp = ef", for instance, to cause the connections to have the relevant
72 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
73
74 Similarly for inbound connections, there is a new control modifier, dscp,
75 so "warn control = dscp/ef" in the connect ACL, or after authentication.
76
77 Supported values depend upon system libraries. "exim -bI:dscp" to list the
78 ones Exim knows of. You can also set a raw number 0..0x3F.
79
80 6. The -G command-line flag is no longer ignored; it is now equivalent to an
81 ACL setting "control = suppress_local_fixups". The -L command-line flag
82 is now accepted and forces use of syslog, with the provided tag as the
83 process name. A few other flags used by Sendmail are now accepted and
84 ignored.
85
86 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
87 ACL modifier; works for single-recipient mails which are recieved on and
88 deliverable via SMTP. Using the connection made for a recipient verify,
89 if requested before the verify, or a new one made for the purpose while
90 the inbound connection is still active. The bulk of the mail item is copied
91 direct from the inbound socket to the outbound (as well as the spool file).
92 When the source notifies the end of data, the data acceptance by the destination
93 is negociated before the acceptance is sent to the source. If the destination
94 does not accept the mail item, for example due to content-scanning, the item
95 is not accepted from the source and therefore there is no need to generate
96 a bounce mail. This is of benefit when providing a secondary-MX service.
97 The downside is that delays are under the control of the ultimate destination
98 system not your own.
99
100 The Recieved-by: header on items delivered by cutthrough is generated
101 early in reception rather than at the end; this will affect any timestamp
102 included. The log line showing delivery is recorded before that showing
103 reception; it uses a new ">>" tag instead of "=>".
104
105 To support the feature, verify-callout connections can now use ESMTP and TLS.
106 The usual smtp transport options are honoured, plus a (new, default everything)
107 hosts_verify_avoid_tls.
108
109 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
110 for specific access to the information for each connection. The old names
111 are present for now but deprecated.
112
113 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING.
114
115 8. New expansion operators ${listnamed:name} to get the content of a named list
116 and ${listcount:string} to count the items in a list.
117
118 9. New global option "gnutls_allow_auto_pkcs11", defaults false. The GnuTLS
119 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
120 modules. For some situations this is desirable, but we expect admin in
121 those situations to know they want the feature. More commonly, it means
122 that GUI user modules get loaded and are broken by the setuid Exim being
123 unable to access files specified in environment variables and passed
124 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
125 unless this new option is set.
126
127 Some older OS's with earlier versions of GnuTLS might not have pkcs11 ability,
128 so have also added a build option which can be used to build Exim with GnuTLS
129 but without trying to use any kind of PKCS11 support. Uncomment this in the
130 Local/Makefile:
131
132 AVOID_GNUTLS_PKCS11=yes
133
134 10. The "acl = name" condition on an ACL now supports optional arguments.
135 New expansion item "${acl {name}{arg}...}" and expansion condition
136 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
137 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
138 Variable $acl_narg contains the number of arguments. If the ACL sets
139 a "message =" value this becomes the result of the expansion item,
140 or the value of $value for the expansion condition. If the ACL returns
141 accept the expansion condition is true; if reject, false. A defer
142 return results in a forced fail.
143
144 11. Routers and transports can now have multiple headers_add and headers_remove
145 option lines. The concatenated list is used.
146
147 12. New ACL modifier "remove_header" can remove headers before message gets
148 handled by routers/transports.
149
150 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
151 "aaaa" and "a" lookups is done and the full set of results returned.
152
153 14. New expansion variable $headers_added with content from ACL add_header
154 modifier (but not yet added to messsage).
155
156 15. New 8bitmime status logging option for received messages. Log field "M8S".
157
158 16. New authenticated_sender logging option, adding to log field "A".
159
160 17. New expansion variables $router_name and $transport_name. Useful
161 particularly for debug_print as -bt commandline option does not
162 require privilege whereas -d does.
163
164 18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
165 proposed extension to SMTP from Eric Hall.
166
167 19. The pipe transport has gained the force_command option, to allow
168 decorating commands from user .forward pipe aliases with prefix
169 wrappers, for instance.
170
171 20. Callout connections can now AUTH; the same controls as normal delivery
172 connections apply.
173
174 21. Support for DMARC, using opendmarc libs, can be enabled. It adds new
175 options: dmarc_forensic_sender, dmarc_history_file, and dmarc_tld_file.
176 It adds new expansion variables $dmarc_ar_header, $dmarc_status,
177 $dmarc_status_text, and $dmarc_used_domain. It adds a new acl modifier
178 dmarc_status. It adds new control flags dmarc_disable_verify and
179 dmarc_enable_forensic.
180
181 22. Add expansion variable $authenticated_fail_id, which is the username
182 provided to the authentication method which failed. It is available
183 for use in subsequent ACL processing (typically quit or notquit ACLs).
184
185 23. New ACL modifer "udpsend" can construct a UDP packet to send to a given
186 UDP host and port.
187
188 24. New ${hexquote:..string..} expansion operator converts non-printable
189 characters in the string to \xNN form.
190
191 25. Experimental TPDA (Transport Post Delivery Action) function added.
192 Patch provided by Axel Rau.
193
194 26. Experimental Redis lookup added. Patch provided by Warren Baker.
195
196
197 Version 4.80
198 ------------
199
200 1. New authenticator driver, "gsasl". Server-only (at present).
201 This is a SASL interface, licensed under GPL, which can be found at
202 http://www.gnu.org/software/gsasl/.
203 This system does not provide sources of data for authentication, so
204 careful use needs to be made of the conditions in Exim.
205
206 2. New authenticator driver, "heimdal_gssapi". Server-only.
207 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
208 is no longer honoured for setuid programs by Heimdal. Use the
209 "server_keytab" option to point to the keytab.
210
211 3. The "pkg-config" system can now be used when building Exim to reference
212 cflags and library information for lookups and authenticators, rather
213 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
214 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
215 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
216
217 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
218 find the headers and libraries for PCRE.
219
220 4. New expansion variable $tls_bits.
221
222 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
223 be joined together with ASCII NUL characters to construct the key to pass
224 into the DBM library. Can be used with gsasl to access sasldb2 files as
225 used by Cyrus SASL.
226
227 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
228
229 Avoid release 1.0.1a if you can. Note that the default value of
230 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
231 increased susceptibility to attack. This may still have interoperability
232 implications for very old clients (see version 4.31 change 37) but
233 administrators can choose to make the trade-off themselves and restore
234 compatibility at the cost of session security.
235
236 7. Use of the new expansion variable $tls_sni in the main configuration option
237 tls_certificate will cause Exim to re-expand the option, if the client
238 sends the TLS Server Name Indication extension, to permit choosing a
239 different certificate; tls_privatekey will also be re-expanded. You must
240 still set these options to expand to valid files when $tls_sni is not set.
241
242 The SMTP Transport has gained the option tls_sni, which will set a hostname
243 for outbound TLS sessions, and set $tls_sni too.
244
245 A new log_selector, +tls_sni, has been added, to log received SNI values
246 for Exim as a server.
247
248 8. The existing "accept_8bitmime" option now defaults to true. This means
249 that Exim is deliberately not strictly RFC compliant. We're following
250 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
251 Those who disagree, or know that they are talking to mail servers that,
252 even today, are not 8-bit clean, need to turn off this option.
253
254 9. Exim can now be started with -bw (with an optional timeout, given as
255 -bw<timespec>). With this, stdin at startup is a socket that is
256 already listening for connections. This has a more modern name of
257 "socket activation", but forcing the activated socket to fd 0. We're
258 interested in adding more support for modern variants.
259
260 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
261 for numbers indicates multiplication by 1024^3.
262
263 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
264 gnutls_require_mac & gnutls_require_protocols are no longer supported.
265 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
266 string, documentation for which is at:
267 http://www.gnutls.org/manual/html_node/Priority-Strings.html
268
269 SNI support has been added to Exim's GnuTLS integration too.
270
271 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
272 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
273
274 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
275 is now available. If the contents of the file are valid, then Exim will
276 send that back in response to a TLS status request; this is OCSP Stapling.
277 Exim will not maintain the contents of the file in any way: administrators
278 are responsible for ensuring that it is up-to-date.
279
280 See "experimental-spec.txt" for more details.
281
282 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
283 identically to TXT record lookups.
284
285 14. New expansion variable $tod_epoch_l for higher-precision time.
286
287 15. New global option tls_dh_max_bits, defaulting to current value of NSS
288 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
289 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
290
291 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
292 Option can now be a path or an identifier for a standard prime.
293 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
294 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
295 primes.
296
297 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
298 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
299 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
300
301
302 Version 4.77
303 ------------
304
305 1. New options for the ratelimit ACL condition: /count= and /unique=.
306 The /noupdate option has been replaced by a /readonly option.
307
308 2. The SMTP transport's protocol option may now be set to "smtps", to
309 use SSL-on-connect outbound.
310
311 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
312 there is a problem talking to the AV scanner, or the AV scanner running.
313
314 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
315 and check if the search item is a member of the list. This does not
316 support named lists, but does subject the list part to string expansion.
317
318 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
319 built, Exim no longer performs string expansion on the second string of
320 the match_* expansion conditions: "match_address", "match_domain",
321 "match_ip" & "match_local_part". Named lists can still be used.
322
323
324 Version 4.76
325 ------------
326
327 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
328 or off in the resolver library.
329
330
331 Version 4.75
332 ------------
333
334 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
335 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
336 libraries. The following global options have been added in support of
337 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
338 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
339
340 2. The pipe transport now takes a boolean option, "freeze_signal", default
341 false. When true, if the external delivery command exits on a signal then
342 Exim will freeze the message in the queue, instead of generating a bounce.
343
344 3. Log filenames may now use %M as an escape, instead of %D (still available).
345 The %M pattern expands to yyyymm, providing month-level resolution.
346
347 4. The $message_linecount variable is now updated for the maildir_tag option,
348 in the same way as $message_size, to reflect the real number of lines,
349 including any header additions or removals from transport.
350
351 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
352 Exim now selects entries randomly, to better scale in a cluster setup.
353
354
355 Version 4.74
356 ------------
357
358 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
359 the flaw permitted the Exim run-time user to cause root to append to
360 arbitrary files of the attacker's choosing, with the content based
361 on content supplied by the attacker.
362
363 2. Exim now supports loading some lookup types at run-time, using your
364 platform's dlopen() functionality. This has limited platform support
365 and the intention is not to support every variant, it's limited to
366 dlopen(). This permits the main Exim binary to not be linked against
367 all the libraries needed for all the lookup types.
368
369
370 Version 4.73
371 ------------
372
373 NOTE: this version is not guaranteed backwards-compatible, please read the
374 items below carefully
375
376 1. A new main configuration option, "openssl_options", is available if Exim
377 is built with SSL support provided by OpenSSL. The option allows
378 administrators to specify OpenSSL options to be used on connections;
379 typically this is to set bug compatibility features which the OpenSSL
380 developers have not enabled by default. There may be security
381 consequences for certain options, so these should not be changed
382 frivolously.
383
384 2. A new pipe transport option, "permit_coredumps", may help with problem
385 diagnosis in some scenarios. Note that Exim is typically installed as
386 a setuid binary, which on most OSes will inhibit coredumps by default,
387 so that safety mechanism would have to be overridden for this option to
388 be able to take effect.
389
390 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
391 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
392 Note that this switches Exim to use a new API ("INSTREAM") and a future
393 release of ClamAV will remove support for the old API ("STREAM").
394
395 The av_scanner option, when set to "clamd", now takes an optional third
396 part, "local", which causes Exim to pass a filename to ClamAV instead of
397 the file content. This is the same behaviour as when clamd is pointed at
398 a Unix-domain socket. For example:
399
400 av_scanner = clamd:192.0.2.3 1234:local
401
402 ClamAV's ExtendedDetectionInfo response format is now handled.
403
404 4. There is now a -bmalware option, restricted to admin users. This option
405 takes one parameter, a filename, and scans that file with Exim's
406 malware-scanning framework. This is intended purely as a debugging aid
407 to ensure that Exim's scanning is working, not to replace other tools.
408 Note that the ACL framework is not invoked, so if av_scanner references
409 ACL variables without a fallback then this will fail.
410
411 5. There is a new expansion operator, "reverse_ip", which will reverse IP
412 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
413
414 ${reverse_ip:192.0.2.4}
415 -> 4.2.0.192
416 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
417 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
418
419 6. There is a new ACL control called "debug", to enable debug logging.
420 This allows selective logging of certain incoming transactions within
421 production environments, with some care. It takes two options, "tag"
422 and "opts"; "tag" is included in the filename of the log and "opts"
423 is used as per the -d<options> command-line option. Examples, which
424 don't all make sense in all contexts:
425
426 control = debug
427 control = debug/tag=.$sender_host_address
428 control = debug/opts=+expand+acl
429 control = debug/tag=.$message_exim_id/opts=+expand
430
431 7. It has always been implicit in the design and the documentation that
432 "the Exim user" is not root. src/EDITME said that using root was
433 "very strongly discouraged". This is not enough to keep people from
434 shooting themselves in the foot in days when many don't configure Exim
435 themselves but via package build managers. The security consequences of
436 running various bits of network code are severe if there should be bugs in
437 them. As such, the Exim user may no longer be root. If configured
438 statically, Exim will refuse to build. If configured as ref:user then Exim
439 will exit shortly after start-up. If you must shoot yourself in the foot,
440 then henceforth you will have to maintain your own local patches to strip
441 the safeties off.
442
443 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
444 condition logic to determine truth/failure and will fail to expand many
445 strings, bool_lax{} uses the router condition logic, where most strings
446 do evaluate true.
447 Note: bool{00} is false, bool_lax{00} is true.
448
449 9. Routers now support multiple "condition" tests.
450
451 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
452 Setting this allows an admin to define which entry in the tcpwrappers
453 config file will be used to control access to the daemon. This option
454 is only available when Exim is built with USE_TCP_WRAPPERS. The
455 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
456 build option.
457
458 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
459 the Exim run-time user, instead of root.
460
461 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
462 is forced on. This is mitigated by the new build option
463 TRUSTED_CONFIG_LIST which defines a list of configuration files which
464 are trusted; one per line. If a config file is owned by root and matches
465 a pathname in the list, then it may be invoked by the Exim build-time
466 user without Exim relinquishing root privileges.
467
468 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
469 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
470 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
471 include the main config. As a transition mechanism, we are temporarily
472 providing a work-around: the new build option WHITELIST_D_MACROS provides
473 a colon-separated list of macro names which may be overridden by the Exim
474 run-time user. The values of these macros are constrained to the regex
475 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
476
477
478 Version 4.72
479 ------------
480
481 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
482 writable, the other to locking of MBX folders (not mbox).
483
484 2. MySQL stored procedures are now supported.
485
486 3. The dkim_domain transport option is now a list, not a single string, and
487 messages will be signed for each element in the list (discarding
488 duplicates).
489
490 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
491 in the presence of multiple character strings within the RR. Prior to 4.70,
492 only the first string would be returned. The dnsdb lookup now, by default,
493 preserves the pre-4.70 semantics, but also now takes an extended output
494 separator specification. The separator can be followed by a semicolon, to
495 concatenate the individual text strings together with no join character,
496 or by a comma and a second separator character, in which case the text
497 strings within a TXT record are joined on that second character.
498 Administrators are reminded that DNS provides no ordering guarantees
499 between multiple records in an RRset. For example:
500
501 foo.example. IN TXT "a" "b" "c"
502 foo.example. IN TXT "d" "e" "f"
503
504 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
505 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
506 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
507
508
509 Version 4.70 / 4.71
510 -------------------
511
512 1. Native DKIM support without an external library.
513 (Note that if no action to prevent it is taken, a straight upgrade will
514 result in DKIM verification of all signed incoming emails. See spec
515 for details on conditionally disabling)
516
517 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
518
519 3. There is now a bool{} expansion condition which maps certain strings to
520 true/false condition values (most likely of use in conjunction with the
521 and{} expansion operator).
522
523 4. The $spam_score, $spam_bar and $spam_report variables are now available
524 at delivery time.
525
526 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
527 options, provided that Exim is invoked by an admin_user.
528
529 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
530 which increases compatibility with older clients at the cost of decreased
531 security. Don't set this unless you need to support such clients.
532
533 7. There is a new expansion operator, ${randint:...} which will produce a
534 "random" number less than the supplied integer. This randomness is
535 not guaranteed to be cryptographically strong, but depending upon how
536 Exim was built may be better than the most naive schemes.
537
538 8. Exim now explicitly ensures that SHA256 is available when linked against
539 OpenSSL.
540
541 9. The transport_filter_timeout option now applies to SMTP transports too.
542
543
544 Version 4.69
545 ------------
546
547 1. Preliminary DKIM support in Experimental.
548
549
550 Version 4.68
551 ------------
552
553 1. The body_linecount and body_zerocount C variables are now exported in the
554 local_scan API.
555
556 2. When a dnslists lookup succeeds, the key that was looked up is now placed
557 in $dnslist_matched. When the key is an IP address, it is not reversed in
558 this variable (though it is, of course, in the actual lookup). In simple
559 cases, for example:
560
561 deny dnslists = spamhaus.example
562
563 the key is also available in another variable (in this case,
564 $sender_host_address). In more complicated cases, however, this is not
565 true. For example, using a data lookup might generate a dnslists lookup
566 like this:
567
568 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
569
570 If this condition succeeds, the value in $dnslist_matched might be
571 192.168.6.7 (for example).
572
573 3. Authenticators now have a client_condition option. When Exim is running as
574 a client, it skips an authenticator whose client_condition expansion yields
575 "0", "no", or "false". This can be used, for example, to skip plain text
576 authenticators when the connection is not encrypted by a setting such as:
577
578 client_condition = ${if !eq{$tls_cipher}{}}
579
580 Note that the 4.67 documentation states that $tls_cipher contains the
581 cipher used for incoming messages. In fact, during SMTP delivery, it
582 contains the cipher used for the delivery. The same is true for
583 $tls_peerdn.
584
585 4. There is now a -Mvc <message-id> option, which outputs a copy of the
586 message to the standard output, in RFC 2822 format. The option can be used
587 only by an admin user.
588
589 5. There is now a /noupdate option for the ratelimit ACL condition. It
590 computes the rate and checks the limit as normal, but it does not update
591 the saved data. This means that, in relevant ACLs, it is possible to lookup
592 the existence of a specified (or auto-generated) ratelimit key without
593 incrementing the ratelimit counter for that key.
594
595 In order for this to be useful, another ACL entry must set the rate
596 for the same key somewhere (otherwise it will always be zero).
597
598 Example:
599
600 acl_check_connect:
601 # Read the rate; if it doesn't exist or is below the maximum
602 # we update it below
603 deny ratelimit = 100 / 5m / strict / noupdate
604 log_message = RATE: $sender_rate / $sender_rate_period \
605 (max $sender_rate_limit)
606
607 [... some other logic and tests...]
608
609 warn ratelimit = 100 / 5m / strict / per_cmd
610 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
611 (max $sender_rate_limit)
612 condition = ${if le{$sender_rate}{$sender_rate_limit}}
613
614 accept
615
616 6. The variable $max_received_linelength contains the number of bytes in the
617 longest line that was received as part of the message, not counting the
618 line termination character(s).
619
620 7. Host lists can now include +ignore_defer and +include_defer, analagous to
621 +ignore_unknown and +include_unknown. These options should be used with
622 care, probably only in non-critical host lists such as whitelists.
623
624 8. There's a new option called queue_only_load_latch, which defaults true.
625 If set false when queue_only_load is greater than zero, Exim re-evaluates
626 the load for each incoming message in an SMTP session. Otherwise, once one
627 message is queued, the remainder are also.
628
629 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
630 cases when an SMTP session ends without sending QUIT. However, when Exim
631 itself is is bad trouble, such as being unable to write to its log files,
632 this ACL is not run, because it might try to do things (such as write to
633 log files) that make the situation even worse.
634
635 Like the QUIT ACL, this new ACL is provided to make it possible to gather
636 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
637 modifier is forbidden in this ACL.
638
639 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
640 to a string that indicates the reason for the termination of the SMTP
641 connection. The possible values are:
642
643 acl-drop Another ACL issued a "drop" command
644 bad-commands Too many unknown or non-mail commands
645 command-timeout Timeout while reading SMTP commands
646 connection-lost The SMTP connection has been lost
647 data-timeout Timeout while reading message data
648 local-scan-error The local_scan() function crashed
649 local-scan-timeout The local_scan() function timed out
650 signal-exit SIGTERM or SIGINT
651 synchronization-error SMTP synchronization error
652 tls-failed TLS failed to start
653
654 In most cases when an SMTP connection is closed without having received
655 QUIT, Exim sends an SMTP response message before actually closing the
656 connection. With the exception of acl-drop, the default message can be
657 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
658 "drop" verb in another ACL, it is the message from the other ACL that is
659 used.
660
661 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
662 servers with individual queries. This is done by starting the query with
663 "servers=x:y:z;", where each item in the list may take one of two forms:
664
665 (1) If it is just a host name, the appropriate global option (mysql_servers
666 or pgsql_servers) is searched for a host of the same name, and the
667 remaining parameters (database, user, password) are taken from there.
668
669 (2) If it contains any slashes, it is taken as a complete parameter set.
670
671 The list of servers is used in exactly the same was as the global list.
672 Once a connection to a server has happened and a query has been
673 successfully executed, processing of the lookup ceases.
674
675 This feature is intended for use in master/slave situations where updates
676 are occurring, and one wants to update a master rather than a slave. If the
677 masters are in the list for reading, you might have:
678
679 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
680
681 In an updating lookup, you could then write
682
683 ${lookup mysql{servers=master; UPDATE ...}
684
685 If, on the other hand, the master is not to be used for reading lookups:
686
687 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
688
689 you can still update the master by
690
691 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
692
693 11. The message_body_newlines option (default FALSE, for backwards
694 compatibility) can be used to control whether newlines are present in
695 $message_body and $message_body_end. If it is FALSE, they are replaced by
696 spaces.
697
698
699 Version 4.67
700 ------------
701
702 1. There is a new log selector called smtp_no_mail, which is not included in
703 the default setting. When it is set, a line is written to the main log
704 whenever an accepted SMTP connection terminates without having issued a
705 MAIL command.
706
707 2. When an item in a dnslists list is followed by = and & and a list of IP
708 addresses, the behaviour was not clear when the lookup returned more than
709 one IP address. This has been solved by the addition of == and =& for "all"
710 rather than the default "any" matching.
711
712 3. Up till now, the only control over which cipher suites GnuTLS uses has been
713 for the cipher algorithms. New options have been added to allow some of the
714 other parameters to be varied.
715
716 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
717 set, Exim compiles a runtime option called disable_fsync.
718
719 5. There is a new variable called $smtp_count_at_connection_start.
720
721 6. There's a new control called no_pipelining.
722
723 7. There are two new variables called $sending_ip_address and $sending_port.
724 These are set whenever an SMTP connection to another host has been set up.
725
726 8. The expansion of the helo_data option in the smtp transport now happens
727 after the connection to the server has been made.
728
729 9. There is a new expansion operator ${rfc2047d: that decodes strings that
730 are encoded as per RFC 2047.
731
732 10. There is a new log selector called "pid", which causes the current process
733 id to be added to every log line, in square brackets, immediately after the
734 time and date.
735
736 11. Exim has been modified so that it flushes SMTP output before implementing
737 a delay in an ACL. It also flushes the output before performing a callout,
738 as this can take a substantial time. These behaviours can be disabled by
739 obeying control = no_delay_flush or control = no_callout_flush,
740 respectively, at some earlier stage of the connection.
741
742 12. There are two new expansion conditions that iterate over a list. They are
743 called forany and forall.
744
745 13. There's a new global option called dsn_from that can be used to vary the
746 contents of From: lines in bounces and other automatically generated
747 messages ("delivery status notifications" - hence the name of the option).
748
749 14. The smtp transport has a new option called hosts_avoid_pipelining.
750
751 15. By default, exigrep does case-insensitive matches. There is now a -I option
752 that makes it case-sensitive.
753
754 16. A number of new features ("addresses", "map", "filter", and "reduce") have
755 been added to string expansions to make it easier to process lists of
756 items, typically addresses.
757
758 17. There's a new ACL modifier called "continue". It does nothing of itself,
759 and processing of the ACL always continues with the next condition or
760 modifier. It is provided so that the side effects of expanding its argument
761 can be used.
762
763 18. It is now possible to use newline and other control characters (those with
764 values less than 32, plus DEL) as separators in lists.
765
766 19. The exigrep utility now has a -v option, which inverts the matching
767 condition.
768
769 20. The host_find_failed option in the manualroute router can now be set to
770 "ignore".
771
772
773 Version 4.66
774 ------------
775
776 No new features were added to 4.66.
777
778
779 Version 4.65
780 ------------
781
782 No new features were added to 4.65.
783
784
785 Version 4.64
786 ------------
787
788 1. ACL variables can now be given arbitrary names, as long as they start with
789 "acl_c" or "acl_m" (for connection variables and message variables), are at
790 least six characters long, with the sixth character being either a digit or
791 an underscore.
792
793 2. There is a new ACL modifier called log_reject_target. It makes it possible
794 to specify which logs are used for messages about ACL rejections.
795
796 3. There is a new authenticator called "dovecot". This is an interface to the
797 authentication facility of the Dovecot POP/IMAP server, which can support a
798 number of authentication methods.
799
800 4. The variable $message_headers_raw provides a concatenation of all the
801 messages's headers without any decoding. This is in contrast to
802 $message_headers, which does RFC2047 decoding on the header contents.
803
804 5. In a DNS black list, if two domain names, comma-separated, are given, the
805 second is used first to do an initial check, making use of any IP value
806 restrictions that are set. If there is a match, the first domain is used,
807 without any IP value restrictions, to get the TXT record.
808
809 6. All authenticators now have a server_condition option.
810
811 7. There is a new command-line option called -Mset. It is useful only in
812 conjunction with -be (that is, when testing string expansions). It must be
813 followed by a message id; Exim loads the given message from its spool
814 before doing the expansions.
815
816 8. Another similar new command-line option is called -bem. It operates like
817 -be except that it must be followed by the name of a file that contains a
818 message.
819
820 9. When an address is delayed because of a 4xx response to a RCPT command, it
821 is now the combination of sender and recipient that is delayed in
822 subsequent queue runs until its retry time is reached.
823
824 10. Unary negation and the bitwise logical operators and, or, xor, not, and
825 shift, have been added to the eval: and eval10: expansion items.
826
827 11. The variables $interface_address and $interface_port have been renamed
828 as $received_ip_address and $received_port, to make it clear that they
829 relate to message reception rather than delivery. (The old names remain
830 available for compatibility.)
831
832 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
833 to vary the message that is sent when an SMTP command is accepted.
834
835
836 Version 4.63
837 ------------
838
839 1. There is a new Boolean option called filter_prepend_home for the redirect
840 router.
841
842 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
843 start of receiving a non-SMTP message, before any of the message has been
844 read.
845
846 3. When an SMTP error message is specified in a "message" modifier in an ACL,
847 or in a :fail: or :defer: message in a redirect router, Exim now checks the
848 start of the message for an SMTP error code.
849
850 4. There is a new parameter for LDAP lookups called "referrals", which takes
851 one of the settings "follow" (the default) or "nofollow".
852
853 5. Version 20070721.2 of exipick now included, offering these new options:
854 --reverse
855 After all other sorting options have bee processed, reverse order
856 before displaying messages (-R is synonym).
857 --random
858 Randomize order of matching messages before displaying.
859 --size
860 Instead of displaying the matching messages, display the sum
861 of their sizes.
862 --sort <variable>[,<variable>...]
863 Before displaying matching messages, sort the messages according to
864 each messages value for each variable.
865 --not
866 Negate the value for every test (returns inverse output from the
867 same criteria without --not).
868
869
870 Version 4.62
871 ------------
872
873 1. The ${readsocket expansion item now supports Internet domain sockets as well
874 as Unix domain sockets. If the first argument begins "inet:", it must be of
875 the form "inet:host:port". The port is mandatory; it may be a number or the
876 name of a TCP port in /etc/services. The host may be a name, or it may be an
877 IP address. An ip address may optionally be enclosed in square brackets.
878 This is best for IPv6 addresses. For example:
879
880 ${readsocket{inet:[::1]:1234}{<request data>}...
881
882 Only a single host name may be given, but if looking it up yield more than
883 one IP address, they are each tried in turn until a connection is made. Once
884 a connection has been made, the behaviour is as for ${readsocket with a Unix
885 domain socket.
886
887 2. If a redirect router sets up file or pipe deliveries for more than one
888 incoming address, and the relevant transport has batch_max set greater than
889 one, a batch delivery now occurs.
890
891 3. The appendfile transport has a new option called maildirfolder_create_regex.
892 Its value is a regular expression. For a maildir delivery, this is matched
893 against the maildir directory; if it matches, Exim ensures that a
894 maildirfolder file is created alongside the new, cur, and tmp directories.
895
896
897 Version 4.61
898 ------------
899
900 The documentation is up-to-date for the 4.61 release. Major new features since
901 the 4.60 release are:
902
903 . An option called disable_ipv6, to disable the use of IPv6 completely.
904
905 . An increase in the number of ACL variables to 20 of each type.
906
907 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
908 $2, $3, (though those are still set) because the numeric variables get used
909 for other things in complicated expansions.
910
911 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
912
913 . It is possible to use setclassresources() on some BSD OS to control the
914 resources used in pipe deliveries.
915
916 . A new ACL modifier called add_header, which can be used with any verb.
917
918 . More errors are detectable in retry rules.
919
920 There are a number of other additions too.
921
922
923 Version 4.60
924 ------------
925
926 The documentation is up-to-date for the 4.60 release. Major new features since
927 the 4.50 release are:
928
929 . Support for SQLite.
930
931 . Support for IGNOREQUOTA in LMTP.
932
933 . Extensions to the "submission mode" features.
934
935 . Support for Client SMTP Authorization (CSA).
936
937 . Support for ratelimiting hosts and users.
938
939 . New expansion items to help with the BATV "prvs" scheme.
940
941 . A "match_ip" condition, that matches an IP address against a list.
942
943 There are many more minor changes.
944
945 ****