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