Added DCC entry to Changelog as GF/01 (2nd attempt)
[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_use_dnssec; 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.
39
40 Current status: work-in-progress; $sender_host_dnssec variable added.
41
42 5. DSCP support for outbound connections: on a transport using the smtp driver,
43 set "dscp = ef", for instance, to cause the connections to have the relevant
44 DSCP (IPv4 TOS or IPv6 TCLASS) value in the header.
45
46 Similarly for inbound connections, there is a new control modifier, dscp,
47 so "warn control = dscp/ef" in the connect ACL, or after authentication.
48
49 Supported values depend upon system libraries. "exim -bI:dscp" to list the
50 ones Exim knows of. You can also set a raw number 0..0x3F.
51
52 6. The -G command-line flag is no longer ignored; it is now equivalent to an
53 ACL setting "control = suppress_local_fixups". The -L command-line flag
54 is now accepted and forces use of syslog, with the provided tag as the
55 process name. A few other flags used by Sendmail are now accepted and
56 ignored.
57
58 7. New cutthrough routing feature. Requested by a "control = cutthrough_delivery"
59 ACL modifier; works for single-recipient mails which are recieved on and
60 deliverable via SMTP. Using the connection made for a recipient verify,
61 if requested before the verify, or a new one made for the purpose while
62 the inbound connection is still active. The bulk of the mail item is copied
63 direct from the inbound socket to the outbound (as well as the spool file).
64 When the source notifies the end of data, the data acceptance by the destination
65 is negociated before the acceptance is sent to the source. If the destination
66 does not accept the mail item, for example due to content-scanning, the item
67 is not accepted from the source and therefore there is no need to generate
68 a bounce mail. This is of benefit when providing a secondary-MX service.
69 The downside is that delays are under the control of the ultimate destination
70 system not your own.
71
72 The Recieved-by: header on items delivered by cutthrough is generated
73 early in reception rather than at the end; this will affect any timestamp
74 included. The log line showing delivery is recorded before that showing
75 reception; it uses a new ">>" tag instead of "=>".
76
77 To support the feature, verify-callout connections can now use ESMTP and TLS.
78 The usual smtp transport options are honoured, plus a (new, default everything)
79 hosts_verify_avoid_tls.
80
81 New variable families named tls_in_cipher, tls_out_cipher etc. are introduced
82 for specific access to the information for each connection. The old names
83 are present for now but deprecated.
84
85 Not yet supported: IGNOREQUOTA, SIZE, PIPELINING, AUTH.
86
87 8. New expansion operators ${listnamed:name} to get the content of a named list
88 and ${listcount:string} to count the items in a list.
89
90 9. New global option "gnutls_enable_pkcs11", defaults false. The GnuTLS
91 rewrite in 4.80 combines with GnuTLS 2.12.0 or later, to autoload PKCS11
92 modules. For some situations this is desirable, but we expect admin in
93 those situations to know they want the feature. More commonly, it means
94 that GUI user modules get loaded and are broken by the setuid Exim being
95 unable to access files specified in environment variables and passed
96 through, thus breakage. So we explicitly inhibit the PKCS11 initialisation
97 unless this new option is set.
98
99 10. The "acl = name" condition on an ACL now supports optional arguments.
100 New expansion item "${acl {name}{arg}...}" and expansion condition
101 "acl {{name}{arg}...}" are added. In all cases up to nine arguments
102 can be used, appearing in $acl_arg1 to $acl_arg9 for the called ACL.
103 Variable $acl_narg contains the number of arguments. If the ACL sets
104 a "message =" value this becomes the result of the expansion item,
105 or the value of $value for the expansion condition. If the ACL returns
106 accept the expansion condition is true; if reject, false. A defer
107 return results in a forced fail.
108
109 11. Routers and transports can now have multiple headers_add and headers_remove
110 option lines. The concatenated list is used.
111
112 12. New ACL modifier "remove_header" can remove headers before message gets
113 handled by routers/transports.
114
115 13. New dnsdb lookup pseudo-type "a+". A sequence of "a6" (if configured),
116 "aaaa" and "a" lookups is done and the full set of results returned.
117
118 14. New expansion variable $headers_added with content from ACL add_header
119 modifier (but not yet added to messsage).
120
121 15. New 8bitmime status logging option for received messages. Log field "M8S".
122
123 16. New authenticated_sender logging option, adding to log field "A".
124
125
126 Version 4.80
127 ------------
128
129 1. New authenticator driver, "gsasl". Server-only (at present).
130 This is a SASL interface, licensed under GPL, which can be found at
131 http://www.gnu.org/software/gsasl/.
132 This system does not provide sources of data for authentication, so
133 careful use needs to be made of the conditions in Exim.
134
135 2. New authenticator driver, "heimdal_gssapi". Server-only.
136 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
137 is no longer honoured for setuid programs by Heimdal. Use the
138 "server_keytab" option to point to the keytab.
139
140 3. The "pkg-config" system can now be used when building Exim to reference
141 cflags and library information for lookups and authenticators, rather
142 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
143 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
144 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
145
146 In addition, setting PCRE_CONFIG=yes will query the pcre-config tool to
147 find the headers and libraries for PCRE.
148
149 4. New expansion variable $tls_bits.
150
151 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
152 be joined together with ASCII NUL characters to construct the key to pass
153 into the DBM library. Can be used with gsasl to access sasldb2 files as
154 used by Cyrus SASL.
155
156 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
157
158 Avoid release 1.0.1a if you can. Note that the default value of
159 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
160 increased susceptibility to attack. This may still have interoperability
161 implications for very old clients (see version 4.31 change 37) but
162 administrators can choose to make the trade-off themselves and restore
163 compatibility at the cost of session security.
164
165 7. Use of the new expansion variable $tls_sni in the main configuration option
166 tls_certificate will cause Exim to re-expand the option, if the client
167 sends the TLS Server Name Indication extension, to permit choosing a
168 different certificate; tls_privatekey will also be re-expanded. You must
169 still set these options to expand to valid files when $tls_sni is not set.
170
171 The SMTP Transport has gained the option tls_sni, which will set a hostname
172 for outbound TLS sessions, and set $tls_sni too.
173
174 A new log_selector, +tls_sni, has been added, to log received SNI values
175 for Exim as a server.
176
177 8. The existing "accept_8bitmime" option now defaults to true. This means
178 that Exim is deliberately not strictly RFC compliant. We're following
179 Dan Bernstein's advice in http://cr.yp.to/smtp/8bitmime.html by default.
180 Those who disagree, or know that they are talking to mail servers that,
181 even today, are not 8-bit clean, need to turn off this option.
182
183 9. Exim can now be started with -bw (with an optional timeout, given as
184 -bw<timespec>). With this, stdin at startup is a socket that is
185 already listening for connections. This has a more modern name of
186 "socket activation", but forcing the activated socket to fd 0. We're
187 interested in adding more support for modern variants.
188
189 10. ${eval } now uses 64-bit values on supporting platforms. A new "G" suffix
190 for numbers indicates multiplication by 1024^3.
191
192 11. The GnuTLS support has been revamped; the three options gnutls_require_kx,
193 gnutls_require_mac & gnutls_require_protocols are no longer supported.
194 tls_require_ciphers is now parsed by gnutls_priority_init(3) as a priority
195 string, documentation for which is at:
196 http://www.gnu.org/software/gnutls/manual/html_node/Priority-Strings.html
197
198 SNI support has been added to Exim's GnuTLS integration too.
199
200 For sufficiently recent GnuTLS libraries, ${randint:..} will now use
201 gnutls_rnd(), asking for GNUTLS_RND_NONCE level randomness.
202
203 12. With OpenSSL, if built with EXPERIMENTAL_OCSP, a new option tls_ocsp_file
204 is now available. If the contents of the file are valid, then Exim will
205 send that back in response to a TLS status request; this is OCSP Stapling.
206 Exim will not maintain the contents of the file in any way: administrators
207 are responsible for ensuring that it is up-to-date.
208
209 See "experimental-spec.txt" for more details.
210
211 13. ${lookup dnsdb{ }} supports now SPF record types. They are handled
212 identically to TXT record lookups.
213
214 14. New expansion variable $tod_epoch_l for higher-precision time.
215
216 15. New global option tls_dh_max_bits, defaulting to current value of NSS
217 hard-coded limit of DH ephemeral bits, to fix interop problems caused by
218 GnuTLS 2.12 library recommending a bit count higher than NSS supports.
219
220 16. tls_dhparam now used by both OpenSSL and GnuTLS, can be path or identifier.
221 Option can now be a path or an identifier for a standard prime.
222 If unset, we use the DH prime from section 2.2 of RFC 5114, "ike23".
223 Set to "historic" to get the old GnuTLS behaviour of auto-generated DH
224 primes.
225
226 17. SSLv2 now disabled by default in OpenSSL. (Never supported by GnuTLS).
227 Use "openssl_options -no_sslv2" to re-enable support, if your OpenSSL
228 install was not built with OPENSSL_NO_SSL2 ("no-ssl2").
229
230
231 Version 4.77
232 ------------
233
234 1. New options for the ratelimit ACL condition: /count= and /unique=.
235 The /noupdate option has been replaced by a /readonly option.
236
237 2. The SMTP transport's protocol option may now be set to "smtps", to
238 use SSL-on-connect outbound.
239
240 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
241 there is a problem talking to the AV scanner, or the AV scanner running.
242
243 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
244 and check if the search item is a member of the list. This does not
245 support named lists, but does subject the list part to string expansion.
246
247 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
248 built, Exim no longer performs string expansion on the second string of
249 the match_* expansion conditions: "match_address", "match_domain",
250 "match_ip" & "match_local_part". Named lists can still be used.
251
252
253 Version 4.76
254 ------------
255
256 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
257 or off in the resolver library.
258
259
260 Version 4.75
261 ------------
262
263 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
264 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
265 libraries. The following global options have been added in support of
266 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
267 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
268
269 2. The pipe transport now takes a boolean option, "freeze_signal", default
270 false. When true, if the external delivery command exits on a signal then
271 Exim will freeze the message in the queue, instead of generating a bounce.
272
273 3. Log filenames may now use %M as an escape, instead of %D (still available).
274 The %M pattern expands to yyyymm, providing month-level resolution.
275
276 4. The $message_linecount variable is now updated for the maildir_tag option,
277 in the same way as $message_size, to reflect the real number of lines,
278 including any header additions or removals from transport.
279
280 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
281 Exim now selects entries randomly, to better scale in a cluster setup.
282
283
284 Version 4.74
285 ------------
286
287 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
288 the flaw permitted the Exim run-time user to cause root to append to
289 arbitrary files of the attacker's choosing, with the content based
290 on content supplied by the attacker.
291
292 2. Exim now supports loading some lookup types at run-time, using your
293 platform's dlopen() functionality. This has limited platform support
294 and the intention is not to support every variant, it's limited to
295 dlopen(). This permits the main Exim binary to not be linked against
296 all the libraries needed for all the lookup types.
297
298
299 Version 4.73
300 ------------
301
302 NOTE: this version is not guaranteed backwards-compatible, please read the
303 items below carefully
304
305 1. A new main configuration option, "openssl_options", is available if Exim
306 is built with SSL support provided by OpenSSL. The option allows
307 administrators to specify OpenSSL options to be used on connections;
308 typically this is to set bug compatibility features which the OpenSSL
309 developers have not enabled by default. There may be security
310 consequences for certain options, so these should not be changed
311 frivolously.
312
313 2. A new pipe transport option, "permit_coredumps", may help with problem
314 diagnosis in some scenarios. Note that Exim is typically installed as
315 a setuid binary, which on most OSes will inhibit coredumps by default,
316 so that safety mechanism would have to be overridden for this option to
317 be able to take effect.
318
319 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
320 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
321 Note that this switches Exim to use a new API ("INSTREAM") and a future
322 release of ClamAV will remove support for the old API ("STREAM").
323
324 The av_scanner option, when set to "clamd", now takes an optional third
325 part, "local", which causes Exim to pass a filename to ClamAV instead of
326 the file content. This is the same behaviour as when clamd is pointed at
327 a Unix-domain socket. For example:
328
329 av_scanner = clamd:192.0.2.3 1234:local
330
331 ClamAV's ExtendedDetectionInfo response format is now handled.
332
333 4. There is now a -bmalware option, restricted to admin users. This option
334 takes one parameter, a filename, and scans that file with Exim's
335 malware-scanning framework. This is intended purely as a debugging aid
336 to ensure that Exim's scanning is working, not to replace other tools.
337 Note that the ACL framework is not invoked, so if av_scanner references
338 ACL variables without a fallback then this will fail.
339
340 5. There is a new expansion operator, "reverse_ip", which will reverse IP
341 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
342
343 ${reverse_ip:192.0.2.4}
344 -> 4.2.0.192
345 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
346 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
347
348 6. There is a new ACL control called "debug", to enable debug logging.
349 This allows selective logging of certain incoming transactions within
350 production environments, with some care. It takes two options, "tag"
351 and "opts"; "tag" is included in the filename of the log and "opts"
352 is used as per the -d<options> command-line option. Examples, which
353 don't all make sense in all contexts:
354
355 control = debug
356 control = debug/tag=.$sender_host_address
357 control = debug/opts=+expand+acl
358 control = debug/tag=.$message_exim_id/opts=+expand
359
360 7. It has always been implicit in the design and the documentation that
361 "the Exim user" is not root. src/EDITME said that using root was
362 "very strongly discouraged". This is not enough to keep people from
363 shooting themselves in the foot in days when many don't configure Exim
364 themselves but via package build managers. The security consequences of
365 running various bits of network code are severe if there should be bugs in
366 them. As such, the Exim user may no longer be root. If configured
367 statically, Exim will refuse to build. If configured as ref:user then Exim
368 will exit shortly after start-up. If you must shoot yourself in the foot,
369 then henceforth you will have to maintain your own local patches to strip
370 the safeties off.
371
372 8. There is a new expansion condition, bool_lax{}. Where bool{} uses the ACL
373 condition logic to determine truth/failure and will fail to expand many
374 strings, bool_lax{} uses the router condition logic, where most strings
375 do evaluate true.
376 Note: bool{00} is false, bool_lax{00} is true.
377
378 9. Routers now support multiple "condition" tests.
379
380 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
381 Setting this allows an admin to define which entry in the tcpwrappers
382 config file will be used to control access to the daemon. This option
383 is only available when Exim is built with USE_TCP_WRAPPERS. The
384 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
385 build option.
386
387 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
388 the Exim run-time user, instead of root.
389
390 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
391 is forced on. This is mitigated by the new build option
392 TRUSTED_CONFIG_LIST which defines a list of configuration files which
393 are trusted; one per line. If a config file is owned by root and matches
394 a pathname in the list, then it may be invoked by the Exim build-time
395 user without Exim relinquishing root privileges.
396
397 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
398 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
399 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
400 include the main config. As a transition mechanism, we are temporarily
401 providing a work-around: the new build option WHITELIST_D_MACROS provides
402 a colon-separated list of macro names which may be overridden by the Exim
403 run-time user. The values of these macros are constrained to the regex
404 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
405
406
407 Version 4.72
408 ------------
409
410 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
411 writable, the other to locking of MBX folders (not mbox).
412
413 2. MySQL stored procedures are now supported.
414
415 3. The dkim_domain transport option is now a list, not a single string, and
416 messages will be signed for each element in the list (discarding
417 duplicates).
418
419 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
420 in the presence of multiple character strings within the RR. Prior to 4.70,
421 only the first string would be returned. The dnsdb lookup now, by default,
422 preserves the pre-4.70 semantics, but also now takes an extended output
423 separator specification. The separator can be followed by a semicolon, to
424 concatenate the individual text strings together with no join character,
425 or by a comma and a second separator character, in which case the text
426 strings within a TXT record are joined on that second character.
427 Administrators are reminded that DNS provides no ordering guarantees
428 between multiple records in an RRset. For example:
429
430 foo.example. IN TXT "a" "b" "c"
431 foo.example. IN TXT "d" "e" "f"
432
433 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
434 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
435 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
436
437
438 Version 4.70 / 4.71
439 -------------------
440
441 1. Native DKIM support without an external library.
442 (Note that if no action to prevent it is taken, a straight upgrade will
443 result in DKIM verification of all signed incoming emails. See spec
444 for details on conditionally disabling)
445
446 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
447
448 3. There is now a bool{} expansion condition which maps certain strings to
449 true/false condition values (most likely of use in conjunction with the
450 and{} expansion operator).
451
452 4. The $spam_score, $spam_bar and $spam_report variables are now available
453 at delivery time.
454
455 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
456 options, provided that Exim is invoked by an admin_user.
457
458 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
459 which increases compatibility with older clients at the cost of decreased
460 security. Don't set this unless you need to support such clients.
461
462 7. There is a new expansion operator, ${randint:...} which will produce a
463 "random" number less than the supplied integer. This randomness is
464 not guaranteed to be cryptographically strong, but depending upon how
465 Exim was built may be better than the most naive schemes.
466
467 8. Exim now explicitly ensures that SHA256 is available when linked against
468 OpenSSL.
469
470 9. The transport_filter_timeout option now applies to SMTP transports too.
471
472
473 Version 4.69
474 ------------
475
476 1. Preliminary DKIM support in Experimental.
477
478
479 Version 4.68
480 ------------
481
482 1. The body_linecount and body_zerocount C variables are now exported in the
483 local_scan API.
484
485 2. When a dnslists lookup succeeds, the key that was looked up is now placed
486 in $dnslist_matched. When the key is an IP address, it is not reversed in
487 this variable (though it is, of course, in the actual lookup). In simple
488 cases, for example:
489
490 deny dnslists = spamhaus.example
491
492 the key is also available in another variable (in this case,
493 $sender_host_address). In more complicated cases, however, this is not
494 true. For example, using a data lookup might generate a dnslists lookup
495 like this:
496
497 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
498
499 If this condition succeeds, the value in $dnslist_matched might be
500 192.168.6.7 (for example).
501
502 3. Authenticators now have a client_condition option. When Exim is running as
503 a client, it skips an authenticator whose client_condition expansion yields
504 "0", "no", or "false". This can be used, for example, to skip plain text
505 authenticators when the connection is not encrypted by a setting such as:
506
507 client_condition = ${if !eq{$tls_cipher}{}}
508
509 Note that the 4.67 documentation states that $tls_cipher contains the
510 cipher used for incoming messages. In fact, during SMTP delivery, it
511 contains the cipher used for the delivery. The same is true for
512 $tls_peerdn.
513
514 4. There is now a -Mvc <message-id> option, which outputs a copy of the
515 message to the standard output, in RFC 2822 format. The option can be used
516 only by an admin user.
517
518 5. There is now a /noupdate option for the ratelimit ACL condition. It
519 computes the rate and checks the limit as normal, but it does not update
520 the saved data. This means that, in relevant ACLs, it is possible to lookup
521 the existence of a specified (or auto-generated) ratelimit key without
522 incrementing the ratelimit counter for that key.
523
524 In order for this to be useful, another ACL entry must set the rate
525 for the same key somewhere (otherwise it will always be zero).
526
527 Example:
528
529 acl_check_connect:
530 # Read the rate; if it doesn't exist or is below the maximum
531 # we update it below
532 deny ratelimit = 100 / 5m / strict / noupdate
533 log_message = RATE: $sender_rate / $sender_rate_period \
534 (max $sender_rate_limit)
535
536 [... some other logic and tests...]
537
538 warn ratelimit = 100 / 5m / strict / per_cmd
539 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
540 (max $sender_rate_limit)
541 condition = ${if le{$sender_rate}{$sender_rate_limit}}
542
543 accept
544
545 6. The variable $max_received_linelength contains the number of bytes in the
546 longest line that was received as part of the message, not counting the
547 line termination character(s).
548
549 7. Host lists can now include +ignore_defer and +include_defer, analagous to
550 +ignore_unknown and +include_unknown. These options should be used with
551 care, probably only in non-critical host lists such as whitelists.
552
553 8. There's a new option called queue_only_load_latch, which defaults true.
554 If set false when queue_only_load is greater than zero, Exim re-evaluates
555 the load for each incoming message in an SMTP session. Otherwise, once one
556 message is queued, the remainder are also.
557
558 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
559 cases when an SMTP session ends without sending QUIT. However, when Exim
560 itself is is bad trouble, such as being unable to write to its log files,
561 this ACL is not run, because it might try to do things (such as write to
562 log files) that make the situation even worse.
563
564 Like the QUIT ACL, this new ACL is provided to make it possible to gather
565 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
566 modifier is forbidden in this ACL.
567
568 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
569 to a string that indicates the reason for the termination of the SMTP
570 connection. The possible values are:
571
572 acl-drop Another ACL issued a "drop" command
573 bad-commands Too many unknown or non-mail commands
574 command-timeout Timeout while reading SMTP commands
575 connection-lost The SMTP connection has been lost
576 data-timeout Timeout while reading message data
577 local-scan-error The local_scan() function crashed
578 local-scan-timeout The local_scan() function timed out
579 signal-exit SIGTERM or SIGINT
580 synchronization-error SMTP synchronization error
581 tls-failed TLS failed to start
582
583 In most cases when an SMTP connection is closed without having received
584 QUIT, Exim sends an SMTP response message before actually closing the
585 connection. With the exception of acl-drop, the default message can be
586 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
587 "drop" verb in another ACL, it is the message from the other ACL that is
588 used.
589
590 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
591 servers with individual queries. This is done by starting the query with
592 "servers=x:y:z;", where each item in the list may take one of two forms:
593
594 (1) If it is just a host name, the appropriate global option (mysql_servers
595 or pgsql_servers) is searched for a host of the same name, and the
596 remaining parameters (database, user, password) are taken from there.
597
598 (2) If it contains any slashes, it is taken as a complete parameter set.
599
600 The list of servers is used in exactly the same was as the global list.
601 Once a connection to a server has happened and a query has been
602 successfully executed, processing of the lookup ceases.
603
604 This feature is intended for use in master/slave situations where updates
605 are occurring, and one wants to update a master rather than a slave. If the
606 masters are in the list for reading, you might have:
607
608 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
609
610 In an updating lookup, you could then write
611
612 ${lookup mysql{servers=master; UPDATE ...}
613
614 If, on the other hand, the master is not to be used for reading lookups:
615
616 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
617
618 you can still update the master by
619
620 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
621
622 11. The message_body_newlines option (default FALSE, for backwards
623 compatibility) can be used to control whether newlines are present in
624 $message_body and $message_body_end. If it is FALSE, they are replaced by
625 spaces.
626
627
628 Version 4.67
629 ------------
630
631 1. There is a new log selector called smtp_no_mail, which is not included in
632 the default setting. When it is set, a line is written to the main log
633 whenever an accepted SMTP connection terminates without having issued a
634 MAIL command.
635
636 2. When an item in a dnslists list is followed by = and & and a list of IP
637 addresses, the behaviour was not clear when the lookup returned more than
638 one IP address. This has been solved by the addition of == and =& for "all"
639 rather than the default "any" matching.
640
641 3. Up till now, the only control over which cipher suites GnuTLS uses has been
642 for the cipher algorithms. New options have been added to allow some of the
643 other parameters to be varied.
644
645 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
646 set, Exim compiles a runtime option called disable_fsync.
647
648 5. There is a new variable called $smtp_count_at_connection_start.
649
650 6. There's a new control called no_pipelining.
651
652 7. There are two new variables called $sending_ip_address and $sending_port.
653 These are set whenever an SMTP connection to another host has been set up.
654
655 8. The expansion of the helo_data option in the smtp transport now happens
656 after the connection to the server has been made.
657
658 9. There is a new expansion operator ${rfc2047d: that decodes strings that
659 are encoded as per RFC 2047.
660
661 10. There is a new log selector called "pid", which causes the current process
662 id to be added to every log line, in square brackets, immediately after the
663 time and date.
664
665 11. Exim has been modified so that it flushes SMTP output before implementing
666 a delay in an ACL. It also flushes the output before performing a callout,
667 as this can take a substantial time. These behaviours can be disabled by
668 obeying control = no_delay_flush or control = no_callout_flush,
669 respectively, at some earlier stage of the connection.
670
671 12. There are two new expansion conditions that iterate over a list. They are
672 called forany and forall.
673
674 13. There's a new global option called dsn_from that can be used to vary the
675 contents of From: lines in bounces and other automatically generated
676 messages ("delivery status notifications" - hence the name of the option).
677
678 14. The smtp transport has a new option called hosts_avoid_pipelining.
679
680 15. By default, exigrep does case-insensitive matches. There is now a -I option
681 that makes it case-sensitive.
682
683 16. A number of new features ("addresses", "map", "filter", and "reduce") have
684 been added to string expansions to make it easier to process lists of
685 items, typically addresses.
686
687 17. There's a new ACL modifier called "continue". It does nothing of itself,
688 and processing of the ACL always continues with the next condition or
689 modifier. It is provided so that the side effects of expanding its argument
690 can be used.
691
692 18. It is now possible to use newline and other control characters (those with
693 values less than 32, plus DEL) as separators in lists.
694
695 19. The exigrep utility now has a -v option, which inverts the matching
696 condition.
697
698 20. The host_find_failed option in the manualroute router can now be set to
699 "ignore".
700
701
702 Version 4.66
703 ------------
704
705 No new features were added to 4.66.
706
707
708 Version 4.65
709 ------------
710
711 No new features were added to 4.65.
712
713
714 Version 4.64
715 ------------
716
717 1. ACL variables can now be given arbitrary names, as long as they start with
718 "acl_c" or "acl_m" (for connection variables and message variables), are at
719 least six characters long, with the sixth character being either a digit or
720 an underscore.
721
722 2. There is a new ACL modifier called log_reject_target. It makes it possible
723 to specify which logs are used for messages about ACL rejections.
724
725 3. There is a new authenticator called "dovecot". This is an interface to the
726 authentication facility of the Dovecot POP/IMAP server, which can support a
727 number of authentication methods.
728
729 4. The variable $message_headers_raw provides a concatenation of all the
730 messages's headers without any decoding. This is in contrast to
731 $message_headers, which does RFC2047 decoding on the header contents.
732
733 5. In a DNS black list, if two domain names, comma-separated, are given, the
734 second is used first to do an initial check, making use of any IP value
735 restrictions that are set. If there is a match, the first domain is used,
736 without any IP value restrictions, to get the TXT record.
737
738 6. All authenticators now have a server_condition option.
739
740 7. There is a new command-line option called -Mset. It is useful only in
741 conjunction with -be (that is, when testing string expansions). It must be
742 followed by a message id; Exim loads the given message from its spool
743 before doing the expansions.
744
745 8. Another similar new command-line option is called -bem. It operates like
746 -be except that it must be followed by the name of a file that contains a
747 message.
748
749 9. When an address is delayed because of a 4xx response to a RCPT command, it
750 is now the combination of sender and recipient that is delayed in
751 subsequent queue runs until its retry time is reached.
752
753 10. Unary negation and the bitwise logical operators and, or, xor, not, and
754 shift, have been added to the eval: and eval10: expansion items.
755
756 11. The variables $interface_address and $interface_port have been renamed
757 as $received_ip_address and $received_port, to make it clear that they
758 relate to message reception rather than delivery. (The old names remain
759 available for compatibility.)
760
761 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
762 to vary the message that is sent when an SMTP command is accepted.
763
764
765 Version 4.63
766 ------------
767
768 1. There is a new Boolean option called filter_prepend_home for the redirect
769 router.
770
771 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
772 start of receiving a non-SMTP message, before any of the message has been
773 read.
774
775 3. When an SMTP error message is specified in a "message" modifier in an ACL,
776 or in a :fail: or :defer: message in a redirect router, Exim now checks the
777 start of the message for an SMTP error code.
778
779 4. There is a new parameter for LDAP lookups called "referrals", which takes
780 one of the settings "follow" (the default) or "nofollow".
781
782 5. Version 20070721.2 of exipick now included, offering these new options:
783 --reverse
784 After all other sorting options have bee processed, reverse order
785 before displaying messages (-R is synonym).
786 --random
787 Randomize order of matching messages before displaying.
788 --size
789 Instead of displaying the matching messages, display the sum
790 of their sizes.
791 --sort <variable>[,<variable>...]
792 Before displaying matching messages, sort the messages according to
793 each messages value for each variable.
794 --not
795 Negate the value for every test (returns inverse output from the
796 same criteria without --not).
797
798
799 Version 4.62
800 ------------
801
802 1. The ${readsocket expansion item now supports Internet domain sockets as well
803 as Unix domain sockets. If the first argument begins "inet:", it must be of
804 the form "inet:host:port". The port is mandatory; it may be a number or the
805 name of a TCP port in /etc/services. The host may be a name, or it may be an
806 IP address. An ip address may optionally be enclosed in square brackets.
807 This is best for IPv6 addresses. For example:
808
809 ${readsocket{inet:[::1]:1234}{<request data>}...
810
811 Only a single host name may be given, but if looking it up yield more than
812 one IP address, they are each tried in turn until a connection is made. Once
813 a connection has been made, the behaviour is as for ${readsocket with a Unix
814 domain socket.
815
816 2. If a redirect router sets up file or pipe deliveries for more than one
817 incoming address, and the relevant transport has batch_max set greater than
818 one, a batch delivery now occurs.
819
820 3. The appendfile transport has a new option called maildirfolder_create_regex.
821 Its value is a regular expression. For a maildir delivery, this is matched
822 against the maildir directory; if it matches, Exim ensures that a
823 maildirfolder file is created alongside the new, cur, and tmp directories.
824
825
826 Version 4.61
827 ------------
828
829 The documentation is up-to-date for the 4.61 release. Major new features since
830 the 4.60 release are:
831
832 . An option called disable_ipv6, to disable the use of IPv6 completely.
833
834 . An increase in the number of ACL variables to 20 of each type.
835
836 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
837 $2, $3, (though those are still set) because the numeric variables get used
838 for other things in complicated expansions.
839
840 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
841
842 . It is possible to use setclassresources() on some BSD OS to control the
843 resources used in pipe deliveries.
844
845 . A new ACL modifier called add_header, which can be used with any verb.
846
847 . More errors are detectable in retry rules.
848
849 There are a number of other additions too.
850
851
852 Version 4.60
853 ------------
854
855 The documentation is up-to-date for the 4.60 release. Major new features since
856 the 4.50 release are:
857
858 . Support for SQLite.
859
860 . Support for IGNOREQUOTA in LMTP.
861
862 . Extensions to the "submission mode" features.
863
864 . Support for Client SMTP Authorization (CSA).
865
866 . Support for ratelimiting hosts and users.
867
868 . New expansion items to help with the BATV "prvs" scheme.
869
870 . A "match_ip" condition, that matches an IP address against a list.
871
872 There are many more minor changes.
873
874 ****