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.
12 1. New authenticator driver, "gsasl". Server-only (at present).
13 This is a SASL interface, licensed under GPL, which can be found at
14 http://www.gnu.org/software/gsasl/.
15 This system does not provide sources of data for authentication, so
16 careful use needs to be made of the conditions in Exim.
18 2. New authenticator driver, "heimdal_gssapi". Server-only.
19 A replacement for using cyrus_sasl with Heimdal, now that $KRB5_KTNAME
20 is no longer honoured for setuid programs by Heimdal. Use the
21 "server_keytab" option to point to the keytab.
23 3. The "pkg-config" system can now be used when building Exim to reference
24 cflags and library information for lookups and authenticators, rather
25 than having to update "CFLAGS", "AUTH_LIBS", "LOOKUP_INCLUDE" and
26 "LOOKUP_LIBS" directly. Similarly for handling the TLS library support
27 without adjusting "TLS_INCLUDE" and "TLS_LIBS".
29 4. New expansion variable $tls_bits.
31 5. New lookup type, "dbmjz". Key is an Exim list, the elements of which will
32 be joined together with ASCII NUL characters to construct the key to pass
33 into the DBM library. Can be used with gsasl to access sasldb2 files as
36 6. OpenSSL now supports TLS1.1 and TLS1.2 with OpenSSL 1.0.1.
38 Avoid release 1.0.1a if you can. Note that the default value of
39 "openssl_options" is no longer "+dont_insert_empty_fragments", as that
40 increased susceptibility to attack. This may still have interoperability
41 implications for very old clients (see version 4.31 change 37) but
42 administrators can choose to make the trade-off themselves and restore
43 compatibility at the cost of session security.
49 1. New options for the ratelimit ACL condition: /count= and /unique=.
50 The /noupdate option has been replaced by a /readonly option.
52 2. The SMTP transport's protocol option may now be set to "smtps", to
53 use SSL-on-connect outbound.
55 3. New variable $av_failed, set true if the AV scanner deferred; ie, when
56 there is a problem talking to the AV scanner, or the AV scanner running.
58 4. New expansion conditions, "inlist" and "inlisti", which take simple lists
59 and check if the search item is a member of the list. This does not
60 support named lists, but does subject the list part to string expansion.
62 5. Unless the new EXPAND_LISTMATCH_RHS build option is set when Exim was
63 built, Exim no longer performs string expansion on the second string of
64 the match_* expansion conditions: "match_address", "match_domain",
65 "match_ip" & "match_local_part". Named lists can still be used.
71 1. The global option "dns_use_edns0" may be set to coerce EDNS0 usage on
72 or off in the resolver library.
78 1. In addition to the existing LDAP and LDAP/SSL ("ldaps") support, there
79 is now LDAP/TLS support, given sufficiently modern OpenLDAP client
80 libraries. The following global options have been added in support of
81 this: ldap_ca_cert_dir, ldap_ca_cert_file, ldap_cert_file, ldap_cert_key,
82 ldap_cipher_suite, ldap_require_cert, ldap_start_tls.
84 2. The pipe transport now takes a boolean option, "freeze_signal", default
85 false. When true, if the external delivery command exits on a signal then
86 Exim will freeze the message in the queue, instead of generating a bounce.
88 3. Log filenames may now use %M as an escape, instead of %D (still available).
89 The %M pattern expands to yyyymm, providing month-level resolution.
91 4. The $message_linecount variable is now updated for the maildir_tag option,
92 in the same way as $message_size, to reflect the real number of lines,
93 including any header additions or removals from transport.
95 5. When contacting a pool of SpamAssassin servers configured in spamd_address,
96 Exim now selects entries randomly, to better scale in a cluster setup.
102 1. SECURITY FIX: privilege escalation flaw fixed. On Linux (and only Linux)
103 the flaw permitted the Exim run-time user to cause root to append to
104 arbitrary files of the attacker's choosing, with the content based
105 on content supplied by the attacker.
107 2. Exim now supports loading some lookup types at run-time, using your
108 platform's dlopen() functionality. This has limited platform support
109 and the intention is not to support every variant, it's limited to
110 dlopen(). This permits the main Exim binary to not be linked against
111 all the libraries needed for all the lookup types.
117 NOTE: this version is not guaranteed backwards-compatible, please read the
118 items below carefully
120 1. A new main configuration option, "openssl_options", is available if Exim
121 is built with SSL support provided by OpenSSL. The option allows
122 administrators to specify OpenSSL options to be used on connections;
123 typically this is to set bug compatibility features which the OpenSSL
124 developers have not enabled by default. There may be security
125 consequences for certain options, so these should not be changed
128 2. A new pipe transport option, "permit_coredumps", may help with problem
129 diagnosis in some scenarios. Note that Exim is typically installed as
130 a setuid binary, which on most OSes will inhibit coredumps by default,
131 so that safety mechanism would have to be overridden for this option to
132 be able to take effect.
134 3. ClamAV 0.95 is now required for ClamAV support in Exim, unless
135 Local/Makefile sets: WITH_OLD_CLAMAV_STREAM=yes
136 Note that this switches Exim to use a new API ("INSTREAM") and a future
137 release of ClamAV will remove support for the old API ("STREAM").
139 The av_scanner option, when set to "clamd", now takes an optional third
140 part, "local", which causes Exim to pass a filename to ClamAV instead of
141 the file content. This is the same behaviour as when clamd is pointed at
142 a Unix-domain socket. For example:
144 av_scanner = clamd:192.0.2.3 1234:local
146 ClamAV's ExtendedDetectionInfo response format is now handled.
148 4. There is now a -bmalware option, restricted to admin users. This option
149 takes one parameter, a filename, and scans that file with Exim's
150 malware-scanning framework. This is intended purely as a debugging aid
151 to ensure that Exim's scanning is working, not to replace other tools.
152 Note that the ACL framework is not invoked, so if av_scanner references
153 ACL variables without a fallback then this will fail.
155 5. There is a new expansion operator, "reverse_ip", which will reverse IP
156 addresses; IPv4 into dotted quad, IPv6 into dotted nibble. Examples:
158 ${reverse_ip:192.0.2.4}
160 ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
161 -> 3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
163 6. There is a new ACL control called "debug", to enable debug logging.
164 This allows selective logging of certain incoming transactions within
165 production environments, with some care. It takes two options, "tag"
166 and "opts"; "tag" is included in the filename of the log and "opts"
167 is used as per the -d<options> command-line option. Examples, which
168 don't all make sense in all contexts:
171 control = debug/tag=.$sender_host_address
172 control = debug/opts=+expand+acl
173 control = debug/tag=.$message_exim_id/opts=+expand
175 7. It has always been implicit in the design and the documentation that
176 "the Exim user" is not root. src/EDITME said that using root was
177 "very strongly discouraged". This is not enough to keep people from
178 shooting themselves in the foot in days when many don't configure Exim
179 themselves but via package build managers. The security consequences of
180 running various bits of network code are severe if there should be bugs in
181 them. As such, the Exim user may no longer be root. If configured
182 statically, Exim will refuse to build. If configured as ref:user then Exim
183 will exit shortly after start-up. If you must shoot yourself in the foot,
184 then henceforth you will have to maintain your own local patches to strip
187 8. There is a new expansion operator, bool_lax{}. Where bool{} uses the ACL
188 condition logic to determine truth/failure and will fail to expand many
189 strings, bool_lax{} uses the router condition logic, where most strings
191 Note: bool{00} is false, bool_lax{00} is true.
193 9. Routers now support multiple "condition" tests,
195 10. There is now a runtime configuration option "tcp_wrappers_daemon_name".
196 Setting this allows an admin to define which entry in the tcpwrappers
197 config file will be used to control access to the daemon. This option
198 is only available when Exim is built with USE_TCP_WRAPPERS. The
199 default value is set at build time using the TCP_WRAPPERS_DAEMON_NAME
202 11. [POSSIBLE CONFIG BREAKAGE] The default value for system_filter_user is now
203 the Exim run-time user, instead of root.
205 12. [POSSIBLE CONFIG BREAKAGE] ALT_CONFIG_ROOT_ONLY is no longer optional and
206 is forced on. This is mitigated by the new build option
207 TRUSTED_CONFIG_LIST which defines a list of configuration files which
208 are trusted; one per line. If a config file is owned by root and matches
209 a pathname in the list, then it may be invoked by the Exim build-time
210 user without Exim relinquishing root privileges.
212 13. [POSSIBLE CONFIG BREAKAGE] The Exim user is no longer automatically
213 trusted to supply -D<Macro[=Value]> overrides on the command-line. Going
214 forward, we recommend using TRUSTED_CONFIG_LIST with shim configs that
215 include the main config. As a transition mechanism, we are temporarily
216 providing a work-around: the new build option WHITELIST_D_MACROS provides
217 a colon-separated list of macro names which may be overridden by the Exim
218 run-time user. The values of these macros are constrained to the regex
219 ^[A-Za-z0-9_/.-]*$ (which explicitly does allow for empty values).
225 1. TWO SECURITY FIXES: one relating to mail-spools which are globally
226 writable, the other to locking of MBX folders (not mbox).
228 2. MySQL stored procedures are now supported.
230 3. The dkim_domain transport option is now a list, not a single string, and
231 messages will be signed for each element in the list (discarding
234 4. The 4.70 release unexpectedly changed the behaviour of dnsdb TXT lookups
235 in the presence of multiple character strings within the RR. Prior to 4.70,
236 only the first string would be returned. The dnsdb lookup now, by default,
237 preserves the pre-4.70 semantics, but also now takes an extended output
238 separator specification. The separator can be followed by a semicolon, to
239 concatenate the individual text strings together with no join character,
240 or by a comma and a second separator character, in which case the text
241 strings within a TXT record are joined on that second character.
242 Administrators are reminded that DNS provides no ordering guarantees
243 between multiple records in an RRset. For example:
245 foo.example. IN TXT "a" "b" "c"
246 foo.example. IN TXT "d" "e" "f"
248 ${lookup dnsdb{>/ txt=foo.example}} -> "a/d"
249 ${lookup dnsdb{>/; txt=foo.example}} -> "def/abc"
250 ${lookup dnsdb{>/,+ txt=foo.example}} -> "a+b+c/d+e+f"
256 1. Native DKIM support without an external library.
257 (Note that if no action to prevent it is taken, a straight upgrade will
258 result in DKIM verification of all signed incoming emails. See spec
259 for details on conditionally disabling)
261 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
263 3. There is now a bool{} expansion condition which maps certain strings to
264 true/false condition values (most likely of use in conjunction with the
265 and{} expansion operator).
267 4. The $spam_score, $spam_bar and $spam_report variables are now available
270 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
271 options, provided that Exim is invoked by an admin_user.
273 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
274 which increases compatibility with older clients at the cost of decreased
275 security. Don't set this unless you need to support such clients.
277 7. There is a new expansion operator, ${randint:...} which will produce a
278 "random" number less than the supplied integer. This randomness is
279 not guaranteed to be cryptographically strong, but depending upon how
280 Exim was built may be better than the most naive schemes.
282 8. Exim now explicitly ensures that SHA256 is available when linked against
285 9. The transport_filter_timeout option now applies to SMTP transports too.
291 1. Preliminary DKIM support in Experimental.
297 1. The body_linecount and body_zerocount C variables are now exported in the
300 2. When a dnslists lookup succeeds, the key that was looked up is now placed
301 in $dnslist_matched. When the key is an IP address, it is not reversed in
302 this variable (though it is, of course, in the actual lookup). In simple
305 deny dnslists = spamhaus.example
307 the key is also available in another variable (in this case,
308 $sender_host_address). In more complicated cases, however, this is not
309 true. For example, using a data lookup might generate a dnslists lookup
312 deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
314 If this condition succeeds, the value in $dnslist_matched might be
315 192.168.6.7 (for example).
317 3. Authenticators now have a client_condition option. When Exim is running as
318 a client, it skips an authenticator whose client_condition expansion yields
319 "0", "no", or "false". This can be used, for example, to skip plain text
320 authenticators when the connection is not encrypted by a setting such as:
322 client_condition = ${if !eq{$tls_cipher}{}}
324 Note that the 4.67 documentation states that $tls_cipher contains the
325 cipher used for incoming messages. In fact, during SMTP delivery, it
326 contains the cipher used for the delivery. The same is true for
329 4. There is now a -Mvc <message-id> option, which outputs a copy of the
330 message to the standard output, in RFC 2822 format. The option can be used
331 only by an admin user.
333 5. There is now a /noupdate option for the ratelimit ACL condition. It
334 computes the rate and checks the limit as normal, but it does not update
335 the saved data. This means that, in relevant ACLs, it is possible to lookup
336 the existence of a specified (or auto-generated) ratelimit key without
337 incrementing the ratelimit counter for that key.
339 In order for this to be useful, another ACL entry must set the rate
340 for the same key somewhere (otherwise it will always be zero).
345 # Read the rate; if it doesn't exist or is below the maximum
347 deny ratelimit = 100 / 5m / strict / noupdate
348 log_message = RATE: $sender_rate / $sender_rate_period \
349 (max $sender_rate_limit)
351 [... some other logic and tests...]
353 warn ratelimit = 100 / 5m / strict / per_cmd
354 log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
355 (max $sender_rate_limit)
356 condition = ${if le{$sender_rate}{$sender_rate_limit}}
360 6. The variable $max_received_linelength contains the number of bytes in the
361 longest line that was received as part of the message, not counting the
362 line termination character(s).
364 7. Host lists can now include +ignore_defer and +include_defer, analagous to
365 +ignore_unknown and +include_unknown. These options should be used with
366 care, probably only in non-critical host lists such as whitelists.
368 8. There's a new option called queue_only_load_latch, which defaults true.
369 If set false when queue_only_load is greater than zero, Exim re-evaluates
370 the load for each incoming message in an SMTP session. Otherwise, once one
371 message is queued, the remainder are also.
373 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
374 cases when an SMTP session ends without sending QUIT. However, when Exim
375 itself is is bad trouble, such as being unable to write to its log files,
376 this ACL is not run, because it might try to do things (such as write to
377 log files) that make the situation even worse.
379 Like the QUIT ACL, this new ACL is provided to make it possible to gather
380 statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
381 modifier is forbidden in this ACL.
383 When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
384 to a string that indicates the reason for the termination of the SMTP
385 connection. The possible values are:
387 acl-drop Another ACL issued a "drop" command
388 bad-commands Too many unknown or non-mail commands
389 command-timeout Timeout while reading SMTP commands
390 connection-lost The SMTP connection has been lost
391 data-timeout Timeout while reading message data
392 local-scan-error The local_scan() function crashed
393 local-scan-timeout The local_scan() function timed out
394 signal-exit SIGTERM or SIGINT
395 synchronization-error SMTP synchronization error
396 tls-failed TLS failed to start
398 In most cases when an SMTP connection is closed without having received
399 QUIT, Exim sends an SMTP response message before actually closing the
400 connection. With the exception of acl-drop, the default message can be
401 overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
402 "drop" verb in another ACL, it is the message from the other ACL that is
405 10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
406 servers with individual queries. This is done by starting the query with
407 "servers=x:y:z;", where each item in the list may take one of two forms:
409 (1) If it is just a host name, the appropriate global option (mysql_servers
410 or pgsql_servers) is searched for a host of the same name, and the
411 remaining parameters (database, user, password) are taken from there.
413 (2) If it contains any slashes, it is taken as a complete parameter set.
415 The list of servers is used in exactly the same was as the global list.
416 Once a connection to a server has happened and a query has been
417 successfully executed, processing of the lookup ceases.
419 This feature is intended for use in master/slave situations where updates
420 are occurring, and one wants to update a master rather than a slave. If the
421 masters are in the list for reading, you might have:
423 mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
425 In an updating lookup, you could then write
427 ${lookup mysql{servers=master; UPDATE ...}
429 If, on the other hand, the master is not to be used for reading lookups:
431 pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
433 you can still update the master by
435 ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
437 11. The message_body_newlines option (default FALSE, for backwards
438 compatibility) can be used to control whether newlines are present in
439 $message_body and $message_body_end. If it is FALSE, they are replaced by
446 1. There is a new log selector called smtp_no_mail, which is not included in
447 the default setting. When it is set, a line is written to the main log
448 whenever an accepted SMTP connection terminates without having issued a
451 2. When an item in a dnslists list is followed by = and & and a list of IP
452 addresses, the behaviour was not clear when the lookup returned more than
453 one IP address. This has been solved by the addition of == and =& for "all"
454 rather than the default "any" matching.
456 3. Up till now, the only control over which cipher suites GnuTLS uses has been
457 for the cipher algorithms. New options have been added to allow some of the
458 other parameters to be varied.
460 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
461 set, Exim compiles a runtime option called disable_fsync.
463 5. There is a new variable called $smtp_count_at_connection_start.
465 6. There's a new control called no_pipelining.
467 7. There are two new variables called $sending_ip_address and $sending_port.
468 These are set whenever an SMTP connection to another host has been set up.
470 8. The expansion of the helo_data option in the smtp transport now happens
471 after the connection to the server has been made.
473 9. There is a new expansion operator ${rfc2047d: that decodes strings that
474 are encoded as per RFC 2047.
476 10. There is a new log selector called "pid", which causes the current process
477 id to be added to every log line, in square brackets, immediately after the
480 11. Exim has been modified so that it flushes SMTP output before implementing
481 a delay in an ACL. It also flushes the output before performing a callout,
482 as this can take a substantial time. These behaviours can be disabled by
483 obeying control = no_delay_flush or control = no_callout_flush,
484 respectively, at some earlier stage of the connection.
486 12. There are two new expansion conditions that iterate over a list. They are
487 called forany and forall.
489 13. There's a new global option called dsn_from that can be used to vary the
490 contents of From: lines in bounces and other automatically generated
491 messages ("delivery status notifications" - hence the name of the option).
493 14. The smtp transport has a new option called hosts_avoid_pipelining.
495 15. By default, exigrep does case-insensitive matches. There is now a -I option
496 that makes it case-sensitive.
498 16. A number of new features ("addresses", "map", "filter", and "reduce") have
499 been added to string expansions to make it easier to process lists of
500 items, typically addresses.
502 17. There's a new ACL modifier called "continue". It does nothing of itself,
503 and processing of the ACL always continues with the next condition or
504 modifier. It is provided so that the side effects of expanding its argument
507 18. It is now possible to use newline and other control characters (those with
508 values less than 32, plus DEL) as separators in lists.
510 19. The exigrep utility now has a -v option, which inverts the matching
513 20. The host_find_failed option in the manualroute router can now be set to
520 No new features were added to 4.66.
526 No new features were added to 4.65.
532 1. ACL variables can now be given arbitrary names, as long as they start with
533 "acl_c" or "acl_m" (for connection variables and message variables), are at
534 least six characters long, with the sixth character being either a digit or
537 2. There is a new ACL modifier called log_reject_target. It makes it possible
538 to specify which logs are used for messages about ACL rejections.
540 3. There is a new authenticator called "dovecot". This is an interface to the
541 authentication facility of the Dovecot POP/IMAP server, which can support a
542 number of authentication methods.
544 4. The variable $message_headers_raw provides a concatenation of all the
545 messages's headers without any decoding. This is in contrast to
546 $message_headers, which does RFC2047 decoding on the header contents.
548 5. In a DNS black list, if two domain names, comma-separated, are given, the
549 second is used first to do an initial check, making use of any IP value
550 restrictions that are set. If there is a match, the first domain is used,
551 without any IP value restrictions, to get the TXT record.
553 6. All authenticators now have a server_condition option.
555 7. There is a new command-line option called -Mset. It is useful only in
556 conjunction with -be (that is, when testing string expansions). It must be
557 followed by a message id; Exim loads the given message from its spool
558 before doing the expansions.
560 8. Another similar new command-line option is called -bem. It operates like
561 -be except that it must be followed by the name of a file that contains a
564 9. When an address is delayed because of a 4xx response to a RCPT command, it
565 is now the combination of sender and recipient that is delayed in
566 subsequent queue runs until its retry time is reached.
568 10. Unary negation and the bitwise logical operators and, or, xor, not, and
569 shift, have been added to the eval: and eval10: expansion items.
571 11. The variables $interface_address and $interface_port have been renamed
572 as $received_ip_address and $received_port, to make it clear that they
573 relate to message reception rather than delivery. (The old names remain
574 available for compatibility.)
576 12. The "message" modifier can now be used on "accept" and "discard" acl verbs
577 to vary the message that is sent when an SMTP command is accepted.
583 1. There is a new Boolean option called filter_prepend_home for the redirect
586 2. There is a new acl, set by acl_not_smtp_start, which is run right at the
587 start of receiving a non-SMTP message, before any of the message has been
590 3. When an SMTP error message is specified in a "message" modifier in an ACL,
591 or in a :fail: or :defer: message in a redirect router, Exim now checks the
592 start of the message for an SMTP error code.
594 4. There is a new parameter for LDAP lookups called "referrals", which takes
595 one of the settings "follow" (the default) or "nofollow".
597 5. Version 20070721.2 of exipick now included, offering these new options:
599 After all other sorting options have bee processed, reverse order
600 before displaying messages (-R is synonym).
602 Randomize order of matching messages before displaying.
604 Instead of displaying the matching messages, display the sum
606 --sort <variable>[,<variable>...]
607 Before displaying matching messages, sort the messages according to
608 each messages value for each variable.
610 Negate the value for every test (returns inverse output from the
611 same criteria without --not).
617 1. The ${readsocket expansion item now supports Internet domain sockets as well
618 as Unix domain sockets. If the first argument begins "inet:", it must be of
619 the form "inet:host:port". The port is mandatory; it may be a number or the
620 name of a TCP port in /etc/services. The host may be a name, or it may be an
621 IP address. An ip address may optionally be enclosed in square brackets.
622 This is best for IPv6 addresses. For example:
624 ${readsocket{inet:[::1]:1234}{<request data>}...
626 Only a single host name may be given, but if looking it up yield more than
627 one IP address, they are each tried in turn until a connection is made. Once
628 a connection has been made, the behaviour is as for ${readsocket with a Unix
631 2. If a redirect router sets up file or pipe deliveries for more than one
632 incoming address, and the relevant transport has batch_max set greater than
633 one, a batch delivery now occurs.
635 3. The appendfile transport has a new option called maildirfolder_create_regex.
636 Its value is a regular expression. For a maildir delivery, this is matched
637 against the maildir directory; if it matches, Exim ensures that a
638 maildirfolder file is created alongside the new, cur, and tmp directories.
644 The documentation is up-to-date for the 4.61 release. Major new features since
645 the 4.60 release are:
647 . An option called disable_ipv6, to disable the use of IPv6 completely.
649 . An increase in the number of ACL variables to 20 of each type.
651 . A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
652 $2, $3, (though those are still set) because the numeric variables get used
653 for other things in complicated expansions.
655 . The default for rfc1413_query_timeout has been changed from 30s to 5s.
657 . It is possible to use setclassresources() on some BSD OS to control the
658 resources used in pipe deliveries.
660 . A new ACL modifier called add_header, which can be used with any verb.
662 . More errors are detectable in retry rules.
664 There are a number of other additions too.
670 The documentation is up-to-date for the 4.60 release. Major new features since
671 the 4.50 release are:
673 . Support for SQLite.
675 . Support for IGNOREQUOTA in LMTP.
677 . Extensions to the "submission mode" features.
679 . Support for Client SMTP Authorization (CSA).
681 . Support for ratelimiting hosts and users.
683 . New expansion items to help with the BATV "prvs" scheme.
685 . A "match_ip" condition, that matches an IP address against a list.
687 There are many more minor changes.