1 $Cambridge: exim/doc/doc-txt/NewStuff,v 1.161 2009/11/16 19:06:35 nm4 Exp $
6 This file contains descriptions of new features that have been added to Exim.
7 Before a formal release, there may be quite a lot of detail so that people can
8 test from the snapshots or the CVS before the documentation is updated. Once
9 the documentation is updated, this file is reduced to a short list.
15 1. Native DKIM support without an external library.
17 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
19 3. There is now a bool{} expansion condition which maps certain strings to
20 true/false condition values (most likely of use in conjuction with the
21 and{} expansion operator).
23 4. The $spam_score, $spam_bar and $spam_report variables are now available
26 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
27 options, provided that Exim is invoked by an admin_user.
29 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
30 which increases compatibility with older clients at the cost of decreased
31 security. Don't set this unless you need to support such clients.
33 7. There is a new expansion operator, ${randint:...} which will produce a
34 "random" number less than the supplied integer. This randomness is
35 not guaranteed to be cryptographically strong, but depending upon how
36 Exim was built may be better than the most naive schemes.
38 8. Exim now explicitly ensures that SHA256 is available when linked against
41 9. The transport_filter_timeout option now applies to SMTP transports too.
47 1. The body_linecount and body_zerocount C variables are now exported in the
50 2. When a dnslists lookup succeeds, the key that was looked up is now placed
51 in $dnslist_matched. When the key is an IP address, it is not reversed in
52 this variable (though it is, of course, in the actual lookup). In simple
55 deny dnslists = spamhaus.example
57 the key is also available in another variable (in this case,
58 $sender_host_address). In more complicated cases, however, this is not
59 true. For example, using a data lookup might generate a dnslists lookup
62 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
64 If this condition succeeds, the value in $dnslist_matched might be
65 192.168.6.7 (for example).
67 3. Authenticators now have a client_condition option. When Exim is running as
68 a client, it skips an authenticator whose client_condition expansion yields
69 "0", "no", or "false". This can be used, for example, to skip plain text
70 authenticators when the connection is not encrypted by a setting such as:
72 client_condition = ${if !eq{$tls_cipher}{}}
74 Note that the 4.67 documentation states that $tls_cipher contains the
75 cipher used for incoming messages. In fact, during SMTP delivery, it
76 contains the cipher used for the delivery. The same is true for
79 4. There is now a -Mvc <message-id> option, which outputs a copy of the
80 message to the standard output, in RFC 2822 format. The option can be used
81 only by an admin user.
83 5. There is now a /noupdate option for the ratelimit ACL condition. It
84 computes the rate and checks the limit as normal, but it does not update
85 the saved data. This means that, in relevant ACLs, it is possible to lookup
86 the existence of a specified (or auto-generated) ratelimit key without
87 incrementing the ratelimit counter for that key.
89 In order for this to be useful, another ACL entry must set the rate
90 for the same key somewhere (otherwise it will always be zero).
95 # Read the rate; if it doesn't exist or is below the maximum
97 deny ratelimit = 100 / 5m / strict / noupdate
98 log_message = RATE: $sender_rate / $sender_rate_period \
99 (max $sender_rate_limit)
101 [... some other logic and tests...]
103 warn ratelimit = 100 / 5m / strict / per_cmd
104 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
105 (max $sender_rate_limit)
106 condition = ${if le{$sender_rate}{$sender_rate_limit}}
110 6. The variable $max_received_linelength contains the number of bytes in the
111 longest line that was received as part of the message, not counting the
112 line termination character(s).
114 7. Host lists can now include +ignore_defer and +include_defer, analagous to
115 +ignore_unknown and +include_unknown. These options should be used with
116 care, probably only in non-critical host lists such as whitelists.
118 8. There's a new option called queue_only_load_latch, which defaults true.
119 If set false when queue_only_load is greater than zero, Exim re-evaluates
120 the load for each incoming message in an SMTP session. Otherwise, once one
121 message is queued, the remainder are also.
123 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
124 cases when an SMTP session ends without sending QUIT. However, when Exim
125 itself is is bad trouble, such as being unable to write to its log files,
126 this ACL is not run, because it might try to do things (such as write to
127 log files) that make the situation even worse.
129 Like the QUIT ACL, this new ACL is provided to make it possible to gather
130 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
131 modifier is forbidden in this ACL.
133 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
134 to a string that indicates the reason for the termination of the SMTP
135 connection. The possible values are:
137 acl-drop Another ACL issued a "drop" command
138 bad-commands Too many unknown or non-mail commands
139 command-timeout Timeout while reading SMTP commands
140 connection-lost The SMTP connection has been lost
141 data-timeout Timeout while reading message data
142 local-scan-error The local_scan() function crashed
143 local-scan-timeout The local_scan() function timed out
144 signal-exit SIGTERM or SIGINT
145 synchronization-error SMTP synchronization error
146 tls-failed TLS failed to start
148 In most cases when an SMTP connection is closed without having received
149 QUIT, Exim sends an SMTP response message before actually closing the
150 connection. With the exception of acl-drop, the default message can be
151 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
152 "drop" verb in another ACL, it is the message from the other ACL that is
155 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
156 servers with individual queries. This is done by starting the query with
157 "servers=x:y:z;", where each item in the list may take one of two forms:
159 (1) If it is just a host name, the appropriate global option (mysql_servers
160 or pgsql_servers) is searched for a host of the same name, and the
161 remaining parameters (database, user, password) are taken from there.
163 (2) If it contains any slashes, it is taken as a complete parameter set.
165 The list of servers is used in exactly the same was as the global list.
166 Once a connection to a server has happened and a query has been
167 successfully executed, processing of the lookup ceases.
169 This feature is intended for use in master/slave situations where updates
170 are occurring, and one wants to update a master rather than a slave. If the
171 masters are in the list for reading, you might have:
173 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
175 In an updating lookup, you could then write
177 ${lookup mysql{servers=master; UPDATE ...}
179 If, on the other hand, the master is not to be used for reading lookups:
181 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
183 you can still update the master by
185 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
187 11. The message_body_newlines option (default FALSE, for backwards
188 compatibility) can be used to control whether newlines are present in
189 $message_body and $message_body_end. If it is FALSE, they are replaced by
196 1. There is a new log selector called smtp_no_mail, which is not included in
197 the default setting. When it is set, a line is written to the main log
198 whenever an accepted SMTP connection terminates without having issued a
201 2. When an item in a dnslists list is followed by = and & and a list of IP
202 addresses, the behaviour was not clear when the lookup returned more than
203 one IP address. This has been solved by the addition of == and =& for "all"
204 rather than the default "any" matching.
206 3. Up till now, the only control over which cipher suites GnuTLS uses has been
207 for the cipher algorithms. New options have been added to allow some of the
208 other parameters to be varied.
210 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
211 set, Exim compiles a runtime option called disable_fsync.
213 5. There is a new variable called $smtp_count_at_connection_start.
215 6. There's a new control called no_pipelining.
217 7. There are two new variables called $sending_ip_address and $sending_port.
218 These are set whenever an SMTP connection to another host has been set up.
220 8. The expansion of the helo_data option in the smtp transport now happens
221 after the connection to the server has been made.
223 9. There is a new expansion operator ${rfc2047d: that decodes strings that
224 are encoded as per RFC 2047.
226 10. There is a new log selector called "pid", which causes the current process
227 id to be added to every log line, in square brackets, immediately after the
230 11. Exim has been modified so that it flushes SMTP output before implementing
231 a delay in an ACL. It also flushes the output before performing a callout,
232 as this can take a substantial time. These behaviours can be disabled by
233 obeying control = no_delay_flush or control = no_callout_flush,
234 respectively, at some earlier stage of the connection.
236 12. There are two new expansion conditions that iterate over a list. They are
237 called forany and forall.
239 13. There's a new global option called dsn_from that can be used to vary the
240 contents of From: lines in bounces and other automatically generated
241 messages ("delivery status notifications" - hence the name of the option).
243 14. The smtp transport has a new option called hosts_avoid_pipelining.
245 15. By default, exigrep does case-insensitive matches. There is now a -I option
246 that makes it case-sensitive.
248 16. A number of new features ("addresses", "map", "filter", and "reduce") have
249 been added to string expansions to make it easier to process lists of
250 items, typically addresses.
252 17. There's a new ACL modifier called "continue". It does nothing of itself,
253 and processing of the ACL always continues with the next condition or
254 modifier. It is provided so that the side effects of expanding its argument
257 18. It is now possible to use newline and other control characters (those with
258 values less than 32, plus DEL) as separators in lists.
260 19. The exigrep utility now has a -v option, which inverts the matching
263 20. The host_find_failed option in the manualroute router can now be set to
270 No new features were added to 4.66.
276 No new features were added to 4.65.
282 1. ACL variables can now be given arbitrary names, as long as they start with
283 "acl_c" or "acl_m" (for connection variables and message variables), are at
284 least six characters long, with the sixth character being either a digit or
287 2. There is a new ACL modifier called log_reject_target. It makes it possible
288 to specify which logs are used for messages about ACL rejections.
290 3. There is a new authenticator called "dovecot". This is an interface to the
291 authentication facility of the Dovecot POP/IMAP server, which can support a
292 number of authentication methods.
294 4. The variable $message_headers_raw provides a concatenation of all the
295 messages's headers without any decoding. This is in contrast to
296 $message_headers, which does RFC2047 decoding on the header contents.
298 5. In a DNS black list, if two domain names, comma-separated, are given, the
299 second is used first to do an initial check, making use of any IP value
300 restrictions that are set. If there is a match, the first domain is used,
301 without any IP value restrictions, to get the TXT record.
303 6. All authenticators now have a server_condition option.
305 7. There is a new command-line option called -Mset. It is useful only in
306 conjunction with -be (that is, when testing string expansions). It must be
307 followed by a message id; Exim loads the given message from its spool
308 before doing the expansions.
310 8. Another similar new command-line option is called -bem. It operates like
311 -be except that it must be followed by the name of a file that contains a
314 9. When an address is delayed because of a 4xx response to a RCPT command, it
315 is now the combination of sender and recipient that is delayed in
316 subsequent queue runs until its retry time is reached.
318 10. Unary negation and the bitwise logical operators and, or, xor, not, and
319 shift, have been added to the eval: and eval10: expansion items.
321 11. The variables $interface_address and $interface_port have been renamed
322 as $received_ip_address and $received_port, to make it clear that they
323 relate to message reception rather than delivery. (The old names remain
324 available for compatibility.)
326 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
327 to vary the message that is sent when an SMTP command is accepted.
333 1. There is a new Boolean option called filter_prepend_home for the redirect
336 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
337 start of receiving a non-SMTP message, before any of the message has been
340 3. When an SMTP error message is specified in a "message" modifier in an ACL,
341 or in a :fail: or :defer: message in a redirect router, Exim now checks the
342 start of the message for an SMTP error code.
344 4. There is a new parameter for LDAP lookups called "referrals", which takes
345 one of the settings "follow" (the default) or "nofollow".
347 5. Version 20070721.2 of exipick now included, offering these new options:
349 After all other sorting options have bee processed, reverse order
350 before displaying messages (-R is synonym).
352 Randomize order of matching messages before displaying.
354 Instead of displaying the matching messages, display the sum
356 --sort <variable>[,<variable>...]
357 Before displaying matching messages, sort the messages according to
358 each messages value for each variable.
360 Negate the value for every test (returns inverse output from the
361 same criteria without --not).
367 1. The ${readsocket expansion item now supports Internet domain sockets as well
368 as Unix domain sockets. If the first argument begins "inet:", it must be of
369 the form "inet:host:port". The port is mandatory; it may be a number or the
370 name of a TCP port in /etc/services. The host may be a name, or it may be an
371 IP address. An ip address may optionally be enclosed in square brackets.
372 This is best for IPv6 addresses. For example:
374 ${readsocket{inet:[::1]:1234}{<request data>}...
376 Only a single host name may be given, but if looking it up yield more than
377 one IP address, they are each tried in turn until a connection is made. Once
378 a connection has been made, the behaviour is as for ${readsocket with a Unix
381 2. If a redirect router sets up file or pipe deliveries for more than one
382 incoming address, and the relevant transport has batch_max set greater than
383 one, a batch delivery now occurs.
385 3. The appendfile transport has a new option called maildirfolder_create_regex.
386 Its value is a regular expression. For a maildir delivery, this is matched
387 against the maildir directory; if it matches, Exim ensures that a
388 maildirfolder file is created alongside the new, cur, and tmp directories.
394 The documentation is up-to-date for the 4.61 release. Major new features since
395 the 4.60 release are:
397 . An option called disable_ipv6, to disable the use of IPv6 completely.
399 . An increase in the number of ACL variables to 20 of each type.
401 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
402 $2, $3, (though those are still set) because the numeric variables get used
403 for other things in complicated expansions.
405 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
407 . It is possible to use setclassresources() on some BSD OS to control the
408 resources used in pipe deliveries.
410 . A new ACL modifier called add_header, which can be used with any verb.
412 . More errors are detectable in retry rules.
414 There are a number of other additions too.
420 The documentation is up-to-date for the 4.60 release. Major new features since
421 the 4.50 release are:
423 . Support for SQLite.
425 . Support for IGNOREQUOTA in LMTP.
427 . Extensions to the "submission mode" features.
429 . Support for Client SMTP Authorization (CSA).
431 . Support for ratelimiting hosts and users.
433 . New expansion items to help with the BATV "prvs" scheme.
435 . A "match_ip" condition, that matches an IP address against a list.
437 There are many more minor changes.