Rename dns_use_dnssec to dns_dnssec_ok.
[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 4.82
10 ------------
11
12 1. New command-line option -bI:sieve will list all supported sieve extensions
13 of this Exim build on standard output, one per line.
14 ManageSieve (RFC 5804) providers managing scripts for use by Exim should
15 query this to establish the correct list to include in the protocol's
16 SIEVE capability line.
17
18 2. If the -n option is combined with the -bP option, then the name of an
19 emitted option is not output, only the value (if visible to you).
20 For instance, "exim -n -bP pid_file_path" should just emit a pathname
21 followed by a newline, and no other text.
22
23 3. When built with SUPPORT_TLS and USE_GNUTLS, the SMTP transport driver now
24 has a "tls_dh_min_bits" option, to set the minimum acceptable number of
25 bits in the Diffie-Hellman prime offered by a server (in DH ciphersuites)
26 acceptable for security. (Option accepted but ignored if using OpenSSL).
27 Defaults to 1024, the old value. May be lowered only to 512, or raised as
28 far as you like. Raising this may hinder TLS interoperability with other
29 sites and is not currently recommended. Lowering this will permit you to
30 establish a TLS session which is not as secure as you might like.
31
32 Unless you really know what you are doing, leave it alone.
33
34 4. If not built with DISABLE_DNSSEC, Exim now has the main option
35 dns_dnssec_ok; if set to 1 then Exim will initialise the resolver library
36 to send the DO flag to your recursive resolver. If you have a recursive
37 resolver, which can set the Authenticated Data (AD) flag in results, Exim
38 can now detect this. Exim does not perform validation itself, instead
39 relying upon a trusted path to the resolver.
40
41 Current status: work-in-progress; $sender_host_dnssec variable added.
42
43 5. DSCP support for outbound connections: on a transport using the smtp driver,
44 set "dscp = ef", for instance, to cause the connections to have the relevant
45 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
46
47 Similarly for inbound connections, there is a new control modifier, dscp,
48 so "warn control = dscp/ef" in the connect ACL, or after authentication.
49
50 Supported values depend upon system libraries. "exim -bI:dscp" to list the
51 ones Exim knows of. You can also set a raw number 0..0x3F.
52
53 6. The -G command-line flag is no longer ignored; it is now equivalent to an
54 ACL setting "control = suppress_local_fixups". The -L command-line flag
55 is now accepted and forces use of syslog, with the provided tag as the
56 process name. A few other flags used by Sendmail are now accepted and
57 ignored.
58
59 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
60 ACL modifier; works for single-recipient mails which are recieved on and
61 deliverable via SMTP. Using the connection made for a recipient verify,
62 if requested before the verify, or a new one made for the purpose while
63 the inbound connection is still active. The bulk of the mail item is copied
64 direct from the inbound socket to the outbound (as well as the spool file).
65 When the source notifies the end of data, the data acceptance by the destination
66 is negociated before the acceptance is sent to the source. If the destination
67 does not accept the mail item, for example due to content-scanning, the item
68 is not accepted from the source and therefore there is no need to generate
69 a bounce mail. This is of benefit when providing a secondary-MX service.
70 The downside is that delays are under the control of the ultimate destination
71 system not your own.
72
73 The Recieved-by: header on items delivered by cutthrough is generated
74 early in reception rather than at the end; this will affect any timestamp
75 included. The log line showing delivery is recorded before that showing
76 reception; it uses a new ">>" tag instead of "=>".
77
78 To support the feature, verify-callout connections can now use ESMTP and TLS.
79 The usual smtp transport options are honoured, plus a (new, default everything)
80 hosts_verify_avoid_tls.
81
82 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
83 for specific access to the information for each connection. The old names
84 are present for now but deprecated.
85
86 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING, AUTH.
87
88 8. New expansion operators ${listnamed:name} to get the content of a named list
89 and ${listcount:string} to count the items in a list.
90
91 9. New global option "gnutls_enable_pkcs11", defaults false. The GnuTLS
92 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
93 modules. For some situations this is desirable, but we expect admin in
94 those situations to know they want the feature. More commonly, it means
95 that GUI user modules get loaded and are broken by the setuid Exim being
96 unable to access files specified in environment variables and passed
97 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
98 unless this new option is set.
99
100 10. The "acl = name" condition on an ACL now supports optional arguments.
101 New expansion item "${acl {name}{arg}...}" and expansion condition
102 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
103 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
104 Variable $acl_narg contains the number of arguments. If the ACL sets
105 a "message =" value this becomes the result of the expansion item,
106 or the value of $value for the expansion condition. If the ACL returns
107 accept the expansion condition is true; if reject, false. A defer
108 return results in a forced fail.
109
110 11. Routers and transports can now have multiple headers_add and headers_remove
111 option lines. The concatenated list is used.
112
113 12. New ACL modifier "remove_header" can remove headers before message gets
114 handled by routers/transports.
115
116 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
117 "aaaa" and "a" lookups is done and the full set of results returned.
118
119 14. New expansion variable $headers_added with content from ACL add_header
120 modifier (but not yet added to messsage).
121
122 15. New 8bitmime status logging option for received messages. Log field "M8S".
123
124 16. New authenticated_sender logging option, adding to log field "A".
125
126 17. New expansion variables $router_name and $transport_name. Useful
127 particularly for debug_print as -bt commandline option does not
128 require privilege whereas -d does.
129
130 18. If built with EXPERIMENTAL_PRDR, per-recipient data responses per a
131 proposed extension to SMTP from Eric Hall.
132
133
134 Version 4.80
135 ------------
136
137 1. New authenticator driver, "gsasl". Server-only (at present).
138 This is a SASL interface, licensed under GPL, which can be found at
139 http://www.gnu.org/software/gsasl/.
140 This system does not provide sources of data for authentication, so
141 careful use needs to be made of the conditions in Exim.
142
143 2. New authenticator driver, "heimdal_gssapi". Server-only.
144 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
145 is no longer honoured for setuid programs by Heimdal. Use the
146 "server_keytab" option to point to the keytab.
147
148 3. The "pkg-config" system can now be used when building Exim to reference
149 cflags and library information for lookups and authenticators, rather
150 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
151 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
152 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
153
154 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
155 find the headers and libraries for PCRE.
156
157 4. New expansion variable $tls_bits.
158
159 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
160 be joined together with ASCII NUL characters to construct the key to pass
161 into the DBM library. Can be used with gsasl to access sasldb2 files as
162 used by Cyrus SASL.
163
164 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
165
166 Avoid release 1.0.1a if you can. Note that the default value of
167 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
168 increased susceptibility to attack. This may still have interoperability
169 implications for very old clients (see version 4.31 change 37) but
170 administrators can choose to make the trade-off themselves and restore
171 compatibility at the cost of session security.
172
173 7. Use of the new expansion variable $tls_sni in the main configuration option
174 tls_certificate will cause Exim to re-expand the option, if the client
175 sends the TLS Server Name Indication extension, to permit choosing a
176 different certificate; tls_privatekey will also be re-expanded. You must
177 still set these options to expand to valid files when $tls_sni is not set.
178
179 The SMTP Transport has gained the option tls_sni, which will set a hostname
180 for outbound TLS sessions, and set $tls_sni too.
181
182 A new log_selector, +tls_sni, has been added, to log received SNI values
183 for Exim as a server.
184
185 8. The existing "accept_8bitmime" option now defaults to true. This means
186 that Exim is deliberately not strictly RFC compliant. We're following
187 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
188 Those who disagree, or know that they are talking to mail servers that,
189 even today, are not 8-bit clean, need to turn off this option.
190
191 9. Exim can now be started with -bw (with an optional timeout, given as
192 -bw<timespec>). With this, stdin at startup is a socket that is
193 already listening for connections. This has a more modern name of
194 "socket activation", but forcing the activated socket to fd 0. We're
195 interested in adding more support for modern variants.
196
197 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
198 for numbers indicates multiplication by 1024^3.
199
200 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
201 gnutls_require_mac & gnutls_require_protocols are no longer supported.
202 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
203 string, documentation for which is at:
204 http://www.gnu.org/software/gnutls/manual/html_node/Priority-Strings.html
205
206 SNI support has been added to Exim's GnuTLS integration too.
207
208 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
209 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
210
211 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
212 is now available. If the contents of the file are valid, then Exim will
213 send that back in response to a TLS status request; this is OCSP Stapling.
214 Exim will not maintain the contents of the file in any way: administrators
215 are responsible for ensuring that it is up-to-date.
216
217 See "experimental-spec.txt" for more details.
218
219 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
220 identically to TXT record lookups.
221
222 14. New expansion variable $tod_epoch_l for higher-precision time.
223
224 15. New global option tls_dh_max_bits, defaulting to current value of NSS
225 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
226 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
227
228 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
229 Option can now be a path or an identifier for a standard prime.
230 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
231 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
232 primes.
233
234 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
235 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
236 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
237
238
239 Version 4.77
240 ------------
241
242 1. New options for the ratelimit ACL condition: /count= and /unique=.
243 The /noupdate option has been replaced by a /readonly option.
244
245 2. The SMTP transport's protocol option may now be set to "smtps", to
246 use SSL-on-connect outbound.
247
248 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
249 there is a problem talking to the AV scanner, or the AV scanner running.
250
251 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
252 and check if the search item is a member of the list. This does not
253 support named lists, but does subject the list part to string expansion.
254
255 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
256 built, Exim no longer performs string expansion on the second string of
257 the match_* expansion conditions: "match_address", "match_domain",
258 "match_ip" & "match_local_part". Named lists can still be used.
259
260
261 Version 4.76
262 ------------
263
264 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
265 or off in the resolver library.
266
267
268 Version 4.75
269 ------------
270
271 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
272 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
273 libraries. The following global options have been added in support of
274 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
275 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
276
277 2. The pipe transport now takes a boolean option, "freeze_signal", default
278 false. When true, if the external delivery command exits on a signal then
279 Exim will freeze the message in the queue, instead of generating a bounce.
280
281 3. Log filenames may now use %M as an escape, instead of %D (still available).
282 The %M pattern expands to yyyymm, providing month-level resolution.
283
284 4. The $message_linecount variable is now updated for the maildir_tag option,
285 in the same way as $message_size, to reflect the real number of lines,
286 including any header additions or removals from transport.
287
288 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
289 Exim now selects entries randomly, to better scale in a cluster setup.
290
291
292 Version 4.74
293 ------------
294
295 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
296 the flaw permitted the Exim run-time user to cause root to append to
297 arbitrary files of the attacker's choosing, with the content based
298 on content supplied by the attacker.
299
300 2. Exim now supports loading some lookup types at run-time, using your
301 platform's dlopen() functionality. This has limited platform support
302 and the intention is not to support every variant, it's limited to
303 dlopen(). This permits the main Exim binary to not be linked against
304 all the libraries needed for all the lookup types.
305
306
307 Version 4.73
308 ------------
309
310 NOTE: this version is not guaranteed backwards-compatible, please read the
311 items below carefully
312
313 1. A new main configuration option, "openssl_options", is available if Exim
314 is built with SSL support provided by OpenSSL. The option allows
315 administrators to specify OpenSSL options to be used on connections;
316 typically this is to set bug compatibility features which the OpenSSL
317 developers have not enabled by default. There may be security
318 consequences for certain options, so these should not be changed
319 frivolously.
320
321 2. A new pipe transport option, "permit_coredumps", may help with problem
322 diagnosis in some scenarios. Note that Exim is typically installed as
323 a setuid binary, which on most OSes will inhibit coredumps by default,
324 so that safety mechanism would have to be overridden for this option to
325 be able to take effect.
326
327 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
328 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
329 Note that this switches Exim to use a new API ("INSTREAM") and a future
330 release of ClamAV will remove support for the old API ("STREAM").
331
332 The av_scanner option, when set to "clamd", now takes an optional third
333 part, "local", which causes Exim to pass a filename to ClamAV instead of
334 the file content. This is the same behaviour as when clamd is pointed at
335 a Unix-domain socket. For example:
336
337 av_scanner = clamd:192.0.2.3 1234:local
338
339 ClamAV's ExtendedDetectionInfo response format is now handled.
340
341 4. There is now a -bmalware option, restricted to admin users. This option
342 takes one parameter, a filename, and scans that file with Exim's
343 malware-scanning framework. This is intended purely as a debugging aid
344 to ensure that Exim's scanning is working, not to replace other tools.
345 Note that the ACL framework is not invoked, so if av_scanner references
346 ACL variables without a fallback then this will fail.
347
348 5. There is a new expansion operator, "reverse_ip", which will reverse IP
349 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
350
351 ${reverse_ip:192.0.2.4}
352 -> 4.2.0.192
353 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
354 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
355
356 6. There is a new ACL control called "debug", to enable debug logging.
357 This allows selective logging of certain incoming transactions within
358 production environments, with some care. It takes two options, "tag"
359 and "opts"; "tag" is included in the filename of the log and "opts"
360 is used as per the -d<options> command-line option. Examples, which
361 don't all make sense in all contexts:
362
363 control = debug
364 control = debug/tag=.$sender_host_address
365 control = debug/opts=+expand+acl
366 control = debug/tag=.$message_exim_id/opts=+expand
367
368 7. It has always been implicit in the design and the documentation that
369 "the Exim user" is not root. src/EDITME said that using root was
370 "very strongly discouraged". This is not enough to keep people from
371 shooting themselves in the foot in days when many don't configure Exim
372 themselves but via package build managers. The security consequences of
373 running various bits of network code are severe if there should be bugs in
374 them. As such, the Exim user may no longer be root. If configured
375 statically, Exim will refuse to build. If configured as ref:user then Exim
376 will exit shortly after start-up. If you must shoot yourself in the foot,
377 then henceforth you will have to maintain your own local patches to strip
378 the safeties off.
379
380 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
381 condition logic to determine truth/failure and will fail to expand many
382 strings, bool_lax{} uses the router condition logic, where most strings
383 do evaluate true.
384 Note: bool{00} is false, bool_lax{00} is true.
385
386 9. Routers now support multiple "condition" tests.
387
388 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
389 Setting this allows an admin to define which entry in the tcpwrappers
390 config file will be used to control access to the daemon. This option
391 is only available when Exim is built with USE_TCP_WRAPPERS. The
392 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
393 build option.
394
395 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
396 the Exim run-time user, instead of root.
397
398 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
399 is forced on. This is mitigated by the new build option
400 TRUSTED_CONFIG_LIST which defines a list of configuration files which
401 are trusted; one per line. If a config file is owned by root and matches
402 a pathname in the list, then it may be invoked by the Exim build-time
403 user without Exim relinquishing root privileges.
404
405 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
406 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
407 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
408 include the main config. As a transition mechanism, we are temporarily
409 providing a work-around: the new build option WHITELIST_D_MACROS provides
410 a colon-separated list of macro names which may be overridden by the Exim
411 run-time user. The values of these macros are constrained to the regex
412 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
413
414
415 Version 4.72
416 ------------
417
418 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
419 writable, the other to locking of MBX folders (not mbox).
420
421 2. MySQL stored procedures are now supported.
422
423 3. The dkim_domain transport option is now a list, not a single string, and
424 messages will be signed for each element in the list (discarding
425 duplicates).
426
427 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
428 in the presence of multiple character strings within the RR. Prior to 4.70,
429 only the first string would be returned. The dnsdb lookup now, by default,
430 preserves the pre-4.70 semantics, but also now takes an extended output
431 separator specification. The separator can be followed by a semicolon, to
432 concatenate the individual text strings together with no join character,
433 or by a comma and a second separator character, in which case the text
434 strings within a TXT record are joined on that second character.
435 Administrators are reminded that DNS provides no ordering guarantees
436 between multiple records in an RRset. For example:
437
438 foo.example. IN TXT "a" "b" "c"
439 foo.example. IN TXT "d" "e" "f"
440
441 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
442 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
443 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
444
445
446 Version 4.70 / 4.71
447 -------------------
448
449 1. Native DKIM support without an external library.
450 (Note that if no action to prevent it is taken, a straight upgrade will
451 result in DKIM verification of all signed incoming emails. See spec
452 for details on conditionally disabling)
453
454 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
455
456 3. There is now a bool{} expansion condition which maps certain strings to
457 true/false condition values (most likely of use in conjunction with the
458 and{} expansion operator).
459
460 4. The $spam_score, $spam_bar and $spam_report variables are now available
461 at delivery time.
462
463 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
464 options, provided that Exim is invoked by an admin_user.
465
466 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
467 which increases compatibility with older clients at the cost of decreased
468 security. Don't set this unless you need to support such clients.
469
470 7. There is a new expansion operator, ${randint:...} which will produce a
471 "random" number less than the supplied integer. This randomness is
472 not guaranteed to be cryptographically strong, but depending upon how
473 Exim was built may be better than the most naive schemes.
474
475 8. Exim now explicitly ensures that SHA256 is available when linked against
476 OpenSSL.
477
478 9. The transport_filter_timeout option now applies to SMTP transports too.
479
480
481 Version 4.69
482 ------------
483
484 1. Preliminary DKIM support in Experimental.
485
486
487 Version 4.68
488 ------------
489
490 1. The body_linecount and body_zerocount C variables are now exported in the
491 local_scan API.
492
493 2. When a dnslists lookup succeeds, the key that was looked up is now placed
494 in $dnslist_matched. When the key is an IP address, it is not reversed in
495 this variable (though it is, of course, in the actual lookup). In simple
496 cases, for example:
497
498 deny dnslists = spamhaus.example
499
500 the key is also available in another variable (in this case,
501 $sender_host_address). In more complicated cases, however, this is not
502 true. For example, using a data lookup might generate a dnslists lookup
503 like this:
504
505 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
506
507 If this condition succeeds, the value in $dnslist_matched might be
508 192.168.6.7 (for example).
509
510 3. Authenticators now have a client_condition option. When Exim is running as
511 a client, it skips an authenticator whose client_condition expansion yields
512 "0", "no", or "false". This can be used, for example, to skip plain text
513 authenticators when the connection is not encrypted by a setting such as:
514
515 client_condition = ${if !eq{$tls_cipher}{}}
516
517 Note that the 4.67 documentation states that $tls_cipher contains the
518 cipher used for incoming messages. In fact, during SMTP delivery, it
519 contains the cipher used for the delivery. The same is true for
520 $tls_peerdn.
521
522 4. There is now a -Mvc <message-id> option, which outputs a copy of the
523 message to the standard output, in RFC 2822 format. The option can be used
524 only by an admin user.
525
526 5. There is now a /noupdate option for the ratelimit ACL condition. It
527 computes the rate and checks the limit as normal, but it does not update
528 the saved data. This means that, in relevant ACLs, it is possible to lookup
529 the existence of a specified (or auto-generated) ratelimit key without
530 incrementing the ratelimit counter for that key.
531
532 In order for this to be useful, another ACL entry must set the rate
533 for the same key somewhere (otherwise it will always be zero).
534
535 Example:
536
537 acl_check_connect:
538 # Read the rate; if it doesn't exist or is below the maximum
539 # we update it below
540 deny ratelimit = 100 / 5m / strict / noupdate
541 log_message = RATE: $sender_rate / $sender_rate_period \
542 (max $sender_rate_limit)
543
544 [... some other logic and tests...]
545
546 warn ratelimit = 100 / 5m / strict / per_cmd
547 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
548 (max $sender_rate_limit)
549 condition = ${if le{$sender_rate}{$sender_rate_limit}}
550
551 accept
552
553 6. The variable $max_received_linelength contains the number of bytes in the
554 longest line that was received as part of the message, not counting the
555 line termination character(s).
556
557 7. Host lists can now include +ignore_defer and +include_defer, analagous to
558 +ignore_unknown and +include_unknown. These options should be used with
559 care, probably only in non-critical host lists such as whitelists.
560
561 8. There's a new option called queue_only_load_latch, which defaults true.
562 If set false when queue_only_load is greater than zero, Exim re-evaluates
563 the load for each incoming message in an SMTP session. Otherwise, once one
564 message is queued, the remainder are also.
565
566 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
567 cases when an SMTP session ends without sending QUIT. However, when Exim
568 itself is is bad trouble, such as being unable to write to its log files,
569 this ACL is not run, because it might try to do things (such as write to
570 log files) that make the situation even worse.
571
572 Like the QUIT ACL, this new ACL is provided to make it possible to gather
573 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
574 modifier is forbidden in this ACL.
575
576 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
577 to a string that indicates the reason for the termination of the SMTP
578 connection. The possible values are:
579
580 acl-drop Another ACL issued a "drop" command
581 bad-commands Too many unknown or non-mail commands
582 command-timeout Timeout while reading SMTP commands
583 connection-lost The SMTP connection has been lost
584 data-timeout Timeout while reading message data
585 local-scan-error The local_scan() function crashed
586 local-scan-timeout The local_scan() function timed out
587 signal-exit SIGTERM or SIGINT
588 synchronization-error SMTP synchronization error
589 tls-failed TLS failed to start
590
591 In most cases when an SMTP connection is closed without having received
592 QUIT, Exim sends an SMTP response message before actually closing the
593 connection. With the exception of acl-drop, the default message can be
594 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
595 "drop" verb in another ACL, it is the message from the other ACL that is
596 used.
597
598 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
599 servers with individual queries. This is done by starting the query with
600 "servers=x:y:z;", where each item in the list may take one of two forms:
601
602 (1) If it is just a host name, the appropriate global option (mysql_servers
603 or pgsql_servers) is searched for a host of the same name, and the
604 remaining parameters (database, user, password) are taken from there.
605
606 (2) If it contains any slashes, it is taken as a complete parameter set.
607
608 The list of servers is used in exactly the same was as the global list.
609 Once a connection to a server has happened and a query has been
610 successfully executed, processing of the lookup ceases.
611
612 This feature is intended for use in master/slave situations where updates
613 are occurring, and one wants to update a master rather than a slave. If the
614 masters are in the list for reading, you might have:
615
616 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
617
618 In an updating lookup, you could then write
619
620 ${lookup mysql{servers=master; UPDATE ...}
621
622 If, on the other hand, the master is not to be used for reading lookups:
623
624 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
625
626 you can still update the master by
627
628 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
629
630 11. The message_body_newlines option (default FALSE, for backwards
631 compatibility) can be used to control whether newlines are present in
632 $message_body and $message_body_end. If it is FALSE, they are replaced by
633 spaces.
634
635
636 Version 4.67
637 ------------
638
639 1. There is a new log selector called smtp_no_mail, which is not included in
640 the default setting. When it is set, a line is written to the main log
641 whenever an accepted SMTP connection terminates without having issued a
642 MAIL command.
643
644 2. When an item in a dnslists list is followed by = and & and a list of IP
645 addresses, the behaviour was not clear when the lookup returned more than
646 one IP address. This has been solved by the addition of == and =& for "all"
647 rather than the default "any" matching.
648
649 3. Up till now, the only control over which cipher suites GnuTLS uses has been
650 for the cipher algorithms. New options have been added to allow some of the
651 other parameters to be varied.
652
653 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
654 set, Exim compiles a runtime option called disable_fsync.
655
656 5. There is a new variable called $smtp_count_at_connection_start.
657
658 6. There's a new control called no_pipelining.
659
660 7. There are two new variables called $sending_ip_address and $sending_port.
661 These are set whenever an SMTP connection to another host has been set up.
662
663 8. The expansion of the helo_data option in the smtp transport now happens
664 after the connection to the server has been made.
665
666 9. There is a new expansion operator ${rfc2047d: that decodes strings that
667 are encoded as per RFC 2047.
668
669 10. There is a new log selector called "pid", which causes the current process
670 id to be added to every log line, in square brackets, immediately after the
671 time and date.
672
673 11. Exim has been modified so that it flushes SMTP output before implementing
674 a delay in an ACL. It also flushes the output before performing a callout,
675 as this can take a substantial time. These behaviours can be disabled by
676 obeying control = no_delay_flush or control = no_callout_flush,
677 respectively, at some earlier stage of the connection.
678
679 12. There are two new expansion conditions that iterate over a list. They are
680 called forany and forall.
681
682 13. There's a new global option called dsn_from that can be used to vary the
683 contents of From: lines in bounces and other automatically generated
684 messages ("delivery status notifications" - hence the name of the option).
685
686 14. The smtp transport has a new option called hosts_avoid_pipelining.
687
688 15. By default, exigrep does case-insensitive matches. There is now a -I option
689 that makes it case-sensitive.
690
691 16. A number of new features ("addresses", "map", "filter", and "reduce") have
692 been added to string expansions to make it easier to process lists of
693 items, typically addresses.
694
695 17. There's a new ACL modifier called "continue". It does nothing of itself,
696 and processing of the ACL always continues with the next condition or
697 modifier. It is provided so that the side effects of expanding its argument
698 can be used.
699
700 18. It is now possible to use newline and other control characters (those with
701 values less than 32, plus DEL) as separators in lists.
702
703 19. The exigrep utility now has a -v option, which inverts the matching
704 condition.
705
706 20. The host_find_failed option in the manualroute router can now be set to
707 "ignore".
708
709
710 Version 4.66
711 ------------
712
713 No new features were added to 4.66.
714
715
716 Version 4.65
717 ------------
718
719 No new features were added to 4.65.
720
721
722 Version 4.64
723 ------------
724
725 1. ACL variables can now be given arbitrary names, as long as they start with
726 "acl_c" or "acl_m" (for connection variables and message variables), are at
727 least six characters long, with the sixth character being either a digit or
728 an underscore.
729
730 2. There is a new ACL modifier called log_reject_target. It makes it possible
731 to specify which logs are used for messages about ACL rejections.
732
733 3. There is a new authenticator called "dovecot". This is an interface to the
734 authentication facility of the Dovecot POP/IMAP server, which can support a
735 number of authentication methods.
736
737 4. The variable $message_headers_raw provides a concatenation of all the
738 messages's headers without any decoding. This is in contrast to
739 $message_headers, which does RFC2047 decoding on the header contents.
740
741 5. In a DNS black list, if two domain names, comma-separated, are given, the
742 second is used first to do an initial check, making use of any IP value
743 restrictions that are set. If there is a match, the first domain is used,
744 without any IP value restrictions, to get the TXT record.
745
746 6. All authenticators now have a server_condition option.
747
748 7. There is a new command-line option called -Mset. It is useful only in
749 conjunction with -be (that is, when testing string expansions). It must be
750 followed by a message id; Exim loads the given message from its spool
751 before doing the expansions.
752
753 8. Another similar new command-line option is called -bem. It operates like
754 -be except that it must be followed by the name of a file that contains a
755 message.
756
757 9. When an address is delayed because of a 4xx response to a RCPT command, it
758 is now the combination of sender and recipient that is delayed in
759 subsequent queue runs until its retry time is reached.
760
761 10. Unary negation and the bitwise logical operators and, or, xor, not, and
762 shift, have been added to the eval: and eval10: expansion items.
763
764 11. The variables $interface_address and $interface_port have been renamed
765 as $received_ip_address and $received_port, to make it clear that they
766 relate to message reception rather than delivery. (The old names remain
767 available for compatibility.)
768
769 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
770 to vary the message that is sent when an SMTP command is accepted.
771
772
773 Version 4.63
774 ------------
775
776 1. There is a new Boolean option called filter_prepend_home for the redirect
777 router.
778
779 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
780 start of receiving a non-SMTP message, before any of the message has been
781 read.
782
783 3. When an SMTP error message is specified in a "message" modifier in an ACL,
784 or in a :fail: or :defer: message in a redirect router, Exim now checks the
785 start of the message for an SMTP error code.
786
787 4. There is a new parameter for LDAP lookups called "referrals", which takes
788 one of the settings "follow" (the default) or "nofollow".
789
790 5. Version 20070721.2 of exipick now included, offering these new options:
791 --reverse
792 After all other sorting options have bee processed, reverse order
793 before displaying messages (-R is synonym).
794 --random
795 Randomize order of matching messages before displaying.
796 --size
797 Instead of displaying the matching messages, display the sum
798 of their sizes.
799 --sort <variable>[,<variable>...]
800 Before displaying matching messages, sort the messages according to
801 each messages value for each variable.
802 --not
803 Negate the value for every test (returns inverse output from the
804 same criteria without --not).
805
806
807 Version 4.62
808 ------------
809
810 1. The ${readsocket expansion item now supports Internet domain sockets as well
811 as Unix domain sockets. If the first argument begins "inet:", it must be of
812 the form "inet:host:port". The port is mandatory; it may be a number or the
813 name of a TCP port in /etc/services. The host may be a name, or it may be an
814 IP address. An ip address may optionally be enclosed in square brackets.
815 This is best for IPv6 addresses. For example:
816
817 ${readsocket{inet:[::1]:1234}{<request data>}...
818
819 Only a single host name may be given, but if looking it up yield more than
820 one IP address, they are each tried in turn until a connection is made. Once
821 a connection has been made, the behaviour is as for ${readsocket with a Unix
822 domain socket.
823
824 2. If a redirect router sets up file or pipe deliveries for more than one
825 incoming address, and the relevant transport has batch_max set greater than
826 one, a batch delivery now occurs.
827
828 3. The appendfile transport has a new option called maildirfolder_create_regex.
829 Its value is a regular expression. For a maildir delivery, this is matched
830 against the maildir directory; if it matches, Exim ensures that a
831 maildirfolder file is created alongside the new, cur, and tmp directories.
832
833
834 Version 4.61
835 ------------
836
837 The documentation is up-to-date for the 4.61 release. Major new features since
838 the 4.60 release are:
839
840 . An option called disable_ipv6, to disable the use of IPv6 completely.
841
842 . An increase in the number of ACL variables to 20 of each type.
843
844 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
845 $2, $3, (though those are still set) because the numeric variables get used
846 for other things in complicated expansions.
847
848 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
849
850 . It is possible to use setclassresources() on some BSD OS to control the
851 resources used in pipe deliveries.
852
853 . A new ACL modifier called add_header, which can be used with any verb.
854
855 . More errors are detectable in retry rules.
856
857 There are a number of other additions too.
858
859
860 Version 4.60
861 ------------
862
863 The documentation is up-to-date for the 4.60 release. Major new features since
864 the 4.50 release are:
865
866 . Support for SQLite.
867
868 . Support for IGNOREQUOTA in LMTP.
869
870 . Extensions to the "submission mode" features.
871
872 . Support for Client SMTP Authorization (CSA).
873
874 . Support for ratelimiting hosts and users.
875
876 . New expansion items to help with the BATV "prvs" scheme.
877
878 . A "match_ip" condition, that matches an IP address against a list.
879
880 There are many more minor changes.
881
882 ****