-$Cambridge: exim/doc/doc-txt/NewStuff,v 1.39 2005/05/03 14:20:00 ph10 Exp $
+$Cambridge: exim/doc/doc-txt/NewStuff,v 1.162 2010/01/04 19:35:50 nm4 Exp $
New Features in Exim
--------------------
-This file contains descriptions of new features that have been added to Exim,
-but have not yet made it into the main manual (which is most conveniently
-updated when there is a relatively large batch of changes). The doc/ChangeLog
-file contains a listing of all changes, including bug fixes.
+This file contains descriptions of new features that have been added to Exim.
+Before a formal release, there may be quite a lot of detail so that people can
+test from the snapshots or the CVS before the documentation is updated. Once
+the documentation is updated, this file is reduced to a short list.
-Version 4.51
+Version 4.72
------------
-PH/01 The format in which GnuTLS parameters are written to the gnutls-param
- file in the spool directory has been changed. This change has been made
- to alleviate problems that some people had with the generation of the
- parameters by Exim when /dev/random was exhausted. In this situation,
- Exim would hang until /dev/random acquired some more entropy.
- The new code exports and imports the DH and RSA parameters in PEM
- format. This means that the parameters can be generated externally using
- the certtool command that is part of GnuTLS.
+Version 4.70 / 4.71
+-------------------
- To replace the parameters with new ones, instead of deleting the file
- and letting Exim re-create it, you can generate new parameters using
- certtool and, when this has been done, replace Exim's cache file by
- renaming. The relevant commands are something like this:
+ 1. Native DKIM support without an external library.
- # rm -f new.params
- # touch new.params
- # chown exim:exim new.params
- # chmod 0400 new.params
- # certtool --generate-privkey --bits 512 >new.params
- # echo "" >>new.params
- # certtool --generate-dh-params --bits 1024 >> new.params
- # mv new.params params
+ 2. Experimental DCC support via dccifd (contributed by Wolfgang Breyha).
- If Exim never has to generate the parameters itself, the possibility of
- stalling is removed.
+ 3. There is now a bool{} expansion condition which maps certain strings to
+ true/false condition values (most likely of use in conjuction with the
+ and{} expansion operator).
-PH/02 A new expansion item for dynamically loading and calling a locally-
- written C function is now provided, if Exim is compiled with
+ 4. The $spam_score, $spam_bar and $spam_report variables are now available
+ at delivery time.
- EXPAND_DLFUNC=yes
+ 5. exim -bP now supports "macros", "macro_list" or "macro MACRO_NAME" as
+ options, provided that Exim is invoked by an admin_user.
- set in Local/Makefile. The facility is not included by default (a
- suitable error is given if you try to use it when it is not there.)
+ 6. There is a new option gnutls_compat_mode, when linked against GnuTLS,
+ which increases compatibility with older clients at the cost of decreased
+ security. Don't set this unless you need to support such clients.
- If you enable EXPAND_DLFUNC, you should also be aware of the new redirect
- router option forbid_filter_dlfunc. If you have unprivileged users on
- your system who are permitted to create filter files, you might want to
- set forbid_filter_dlfunc=true in the appropriate router, to stop them
- using ${dlfunc to run code within Exim.
+ 7. There is a new expansion operator, ${randint:...} which will produce a
+ "random" number less than the supplied integer. This randomness is
+ not guaranteed to be cryptographically strong, but depending upon how
+ Exim was built may be better than the most naive schemes.
- You load and call an external function like this:
-
- ${dlfunc{/some/file}{function}{arg1}{arg2}...}
-
- Once loaded, Exim remembers the dynamically loaded object so that it
- doesn't reload the same object file in the same Exim process (but of
- course Exim does start new processes frequently).
-
- There may be from zero to eight arguments to the function. When compiling
- a local function that is to be called in this way, local_scan.h should be
- included. The Exim variables and functions that are defined by that API
- are also available for dynamically loaded functions. The function itself
- must have the following type:
-
- int dlfunction(uschar **yield, int argc, uschar *argv[])
-
- Where "uschar" is a typedef for "unsigned char" in local_scan.h. The
- function should return one of the following values:
-
- OK Success. The string that is placed in "yield" is put into
- the expanded string that is being built.
-
- FAIL A non-forced expansion failure occurs, with the error
- message taken from "yield", if it is set.
-
- FAIL_FORCED A forced expansion failure occurs, with the error message
- taken from "yield" if it is set.
-
- ERROR Same as FAIL, except that a panic log entry is written.
-
- When compiling a function that is to be used in this way with gcc,
- you need to add -shared to the gcc command. Also, in the Exim build-time
- configuration, you must add -export-dynamic to EXTRALIBS.
-
-TF/01 $received_time is a new expansion variable containing the time and date
- as a number of seconds since the start of the Unix epoch when the
- current message was received.
-
-PH/03 There is a new value for RADIUS_LIB_TYPE that can be set in
- Local/Makefile. It is RADIUSCLIENTNEW, and it requests that the new API,
- in use from radiusclient 0.4.0 onwards, be used. It does not appear to be
- possible to detect the different versions automatically.
-
-PH/04 There is a new option called acl_not_smtp_mime that allows you to scan
- MIME parts in non-SMTP messages. It operates in exactly the same way as
- acl_smtp_mime
-
-PH/05 It is now possible to redefine a macro within the configuration file.
- The macro must have been previously defined within the configuration (or
- an included file). A definition on the command line using the -D option
- causes all definitions and redefinitions within the file to be ignored.
- In other words, -D overrides any values that are set in the file.
- Redefinition is specified by using '==' instead of '='. For example:
-
- MAC1 = initial value
- ...
- MAC1 == updated value
-
- Redefinition does not alter the order in which the macros are applied to
- the subsequent lines of the configuration file. It is still the same
- order in which the macros were originally defined. All that changes is
- the macro's value. Redefinition makes it possible to accumulate values.
- For example:
-
- MAC1 = initial value
- ...
- MAC1 == MAC1 and something added
-
- This can be helpful in situations where the configuration file is built
- from a number of other files.
-
-PH/06 Macros may now be defined or redefined between router, transport,
- authenticator, or ACL definitions, as well as in the main part of the
- configuration. They may not, however, be changed within an individual
- driver or ACL, or in the local_scan, retry, or rewrite sections of the
- configuration.
-
-PH/07 $acl_verify_message is now set immediately after the failure of a
- verification in an ACL, and so is available in subsequent modifiers. In
- particular, the message can be preserved by coding like this:
+ 8. Exim now explicitly ensures that SHA256 is available when linked against
+ OpenSSL.
- warn !verify = sender
- set acl_m0 = $acl_verify_message
+ 9. The transport_filter_timeout option now applies to SMTP transports too.
- Previously, $acl_verify_message was set only while expanding "message"
- and "log_message" when a very denied access.
-
-PH/08 The redirect router has two new options, sieve_useraddress and
- sieve_subaddress. These are passed to a Sieve filter to specify the :user
- and :subaddress parts of an address. Both options are unset by default.
- However, when a Sieve filter is run, if sieve_useraddress is unset, the
- entire original local part (including any prefix or suffix) is used for
- :user. An unset subaddress is treated as an empty subaddress.
-
-PH/09 Quota values can be followed by G as well as K and M.
-
-PH/10 $message_linecount is a new variable that contains the total number of
- lines in the header and body of the message. Compare $body_linecount,
- which is the count for the body only. During the DATA and
- content-scanning ACLs, $message_linecount contains the number of lines
- received. Before delivery happens (that is, before filters, routers, and
- transports run) the count is increased to include the Received: header
- line that Exim standardly adds, and also any other header lines that are
- added by ACLs. The blank line that separates the message header from the
- body is not counted. Here is an example of the use of this variable in a
- DATA ACL:
-
- deny message = Too many lines in message header
- condition = \
- ${if <{250}{${eval: $message_linecount - $body_linecount}}}
-
- In the MAIL and RCPT ACLs, the value is zero because at that stage the
- message has not yet been received.
-
-PH/11 In a ${run expansion, the variable $value (which contains the standard
- output) is now also usable in the "else" string.
-
-PH/12 In a pipe transport, although a timeout while waiting for the pipe
- process to complete was treated as a delivery failure, a timeout while
- writing the message to the pipe was logged, but erroneously treated as a
- successful delivery. Such timeouts include transport filter timeouts. For
- consistency with the overall process timeout, these timeouts are now
- treated as errors, giving rise to delivery failures by default. However,
- there is now a new Boolean option for the pipe transport called
- timeout_defer, which, if set TRUE, converts the failures into defers for
- both kinds of timeout. A transport filter timeout is now identified in
- the log output.
-
-
-Version 4.50
+
+Version 4.68
+------------
+
+ 1. The body_linecount and body_zerocount C variables are now exported in the
+ local_scan API.
+
+ 2. When a dnslists lookup succeeds, the key that was looked up is now placed
+ in $dnslist_matched. When the key is an IP address, it is not reversed in
+ this variable (though it is, of course, in the actual lookup). In simple
+ cases, for example:
+
+ deny dnslists = spamhaus.example
+
+ the key is also available in another variable (in this case,
+ $sender_host_address). In more complicated cases, however, this is not
+ true. For example, using a data lookup might generate a dnslists lookup
+ like this:
+
+ deny dnslists = spamhaus.example/<|192.168.1.2|192.168.6.7|...
+
+ If this condition succeeds, the value in $dnslist_matched might be
+ 192.168.6.7 (for example).
+
+ 3. Authenticators now have a client_condition option. When Exim is running as
+ a client, it skips an authenticator whose client_condition expansion yields
+ "0", "no", or "false". This can be used, for example, to skip plain text
+ authenticators when the connection is not encrypted by a setting such as:
+
+ client_condition = ${if !eq{$tls_cipher}{}}
+
+ Note that the 4.67 documentation states that $tls_cipher contains the
+ cipher used for incoming messages. In fact, during SMTP delivery, it
+ contains the cipher used for the delivery. The same is true for
+ $tls_peerdn.
+
+ 4. There is now a -Mvc <message-id> option, which outputs a copy of the
+ message to the standard output, in RFC 2822 format. The option can be used
+ only by an admin user.
+
+ 5. There is now a /noupdate option for the ratelimit ACL condition. It
+ computes the rate and checks the limit as normal, but it does not update
+ the saved data. This means that, in relevant ACLs, it is possible to lookup
+ the existence of a specified (or auto-generated) ratelimit key without
+ incrementing the ratelimit counter for that key.
+
+ In order for this to be useful, another ACL entry must set the rate
+ for the same key somewhere (otherwise it will always be zero).
+
+ Example:
+
+ acl_check_connect:
+ # Read the rate; if it doesn't exist or is below the maximum
+ # we update it below
+ deny ratelimit = 100 / 5m / strict / noupdate
+ log_message = RATE: $sender_rate / $sender_rate_period \
+ (max $sender_rate_limit)
+
+ [... some other logic and tests...]
+
+ warn ratelimit = 100 / 5m / strict / per_cmd
+ log_message = RATE UPDATE: $sender_rate / $sender_rate_period \
+ (max $sender_rate_limit)
+ condition = ${if le{$sender_rate}{$sender_rate_limit}}
+
+ accept
+
+ 6. The variable $max_received_linelength contains the number of bytes in the
+ longest line that was received as part of the message, not counting the
+ line termination character(s).
+
+ 7. Host lists can now include +ignore_defer and +include_defer, analagous to
+ +ignore_unknown and +include_unknown. These options should be used with
+ care, probably only in non-critical host lists such as whitelists.
+
+ 8. There's a new option called queue_only_load_latch, which defaults true.
+ If set false when queue_only_load is greater than zero, Exim re-evaluates
+ the load for each incoming message in an SMTP session. Otherwise, once one
+ message is queued, the remainder are also.
+
+ 9. There is a new ACL, specified by acl_smtp_notquit, which is run in most
+ cases when an SMTP session ends without sending QUIT. However, when Exim
+ itself is is bad trouble, such as being unable to write to its log files,
+ this ACL is not run, because it might try to do things (such as write to
+ log files) that make the situation even worse.
+
+ Like the QUIT ACL, this new ACL is provided to make it possible to gather
+ statistics. Whatever it returns (accept or deny) is immaterial. The "delay"
+ modifier is forbidden in this ACL.
+
+ When the NOTQUIT ACL is running, the variable $smtp_notquit_reason is set
+ to a string that indicates the reason for the termination of the SMTP
+ connection. The possible values are:
+
+ acl-drop Another ACL issued a "drop" command
+ bad-commands Too many unknown or non-mail commands
+ command-timeout Timeout while reading SMTP commands
+ connection-lost The SMTP connection has been lost
+ data-timeout Timeout while reading message data
+ local-scan-error The local_scan() function crashed
+ local-scan-timeout The local_scan() function timed out
+ signal-exit SIGTERM or SIGINT
+ synchronization-error SMTP synchronization error
+ tls-failed TLS failed to start
+
+ In most cases when an SMTP connection is closed without having received
+ QUIT, Exim sends an SMTP response message before actually closing the
+ connection. With the exception of acl-drop, the default message can be
+ overridden by the "message" modifier in the NOTQUIT ACL. In the case of a
+ "drop" verb in another ACL, it is the message from the other ACL that is
+ used.
+
+10. For MySQL and PostgreSQL lookups, it is now possible to specify a list of
+ servers with individual queries. This is done by starting the query with
+ "servers=x:y:z;", where each item in the list may take one of two forms:
+
+ (1) If it is just a host name, the appropriate global option (mysql_servers
+ or pgsql_servers) is searched for a host of the same name, and the
+ remaining parameters (database, user, password) are taken from there.
+
+ (2) If it contains any slashes, it is taken as a complete parameter set.
+
+ The list of servers is used in exactly the same was as the global list.
+ Once a connection to a server has happened and a query has been
+ successfully executed, processing of the lookup ceases.
+
+ This feature is intended for use in master/slave situations where updates
+ are occurring, and one wants to update a master rather than a slave. If the
+ masters are in the list for reading, you might have:
+
+ mysql_servers = slave1/db/name/pw:slave2/db/name/pw:master/db/name/pw
+
+ In an updating lookup, you could then write
+
+ ${lookup mysql{servers=master; UPDATE ...}
+
+ If, on the other hand, the master is not to be used for reading lookups:
+
+ pgsql_servers = slave1/db/name/pw:slave2/db/name/pw
+
+ you can still update the master by
+
+ ${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
+
+11. The message_body_newlines option (default FALSE, for backwards
+ compatibility) can be used to control whether newlines are present in
+ $message_body and $message_body_end. If it is FALSE, they are replaced by
+ spaces.
+
+
+Version 4.67
+------------
+
+ 1. There is a new log selector called smtp_no_mail, which is not included in
+ the default setting. When it is set, a line is written to the main log
+ whenever an accepted SMTP connection terminates without having issued a
+ MAIL command.
+
+ 2. When an item in a dnslists list is followed by = and & and a list of IP
+ addresses, the behaviour was not clear when the lookup returned more than
+ one IP address. This has been solved by the addition of == and =& for "all"
+ rather than the default "any" matching.
+
+ 3. Up till now, the only control over which cipher suites GnuTLS uses has been
+ for the cipher algorithms. New options have been added to allow some of the
+ other parameters to be varied.
+
+ 4. There is a new compile-time option called ENABLE_DISABLE_FSYNC. When it is
+ set, Exim compiles a runtime option called disable_fsync.
+
+ 5. There is a new variable called $smtp_count_at_connection_start.
+
+ 6. There's a new control called no_pipelining.
+
+ 7. There are two new variables called $sending_ip_address and $sending_port.
+ These are set whenever an SMTP connection to another host has been set up.
+
+ 8. The expansion of the helo_data option in the smtp transport now happens
+ after the connection to the server has been made.
+
+ 9. There is a new expansion operator ${rfc2047d: that decodes strings that
+ are encoded as per RFC 2047.
+
+10. There is a new log selector called "pid", which causes the current process
+ id to be added to every log line, in square brackets, immediately after the
+ time and date.
+
+11. Exim has been modified so that it flushes SMTP output before implementing
+ a delay in an ACL. It also flushes the output before performing a callout,
+ as this can take a substantial time. These behaviours can be disabled by
+ obeying control = no_delay_flush or control = no_callout_flush,
+ respectively, at some earlier stage of the connection.
+
+12. There are two new expansion conditions that iterate over a list. They are
+ called forany and forall.
+
+13. There's a new global option called dsn_from that can be used to vary the
+ contents of From: lines in bounces and other automatically generated
+ messages ("delivery status notifications" - hence the name of the option).
+
+14. The smtp transport has a new option called hosts_avoid_pipelining.
+
+15. By default, exigrep does case-insensitive matches. There is now a -I option
+ that makes it case-sensitive.
+
+16. A number of new features ("addresses", "map", "filter", and "reduce") have
+ been added to string expansions to make it easier to process lists of
+ items, typically addresses.
+
+17. There's a new ACL modifier called "continue". It does nothing of itself,
+ and processing of the ACL always continues with the next condition or
+ modifier. It is provided so that the side effects of expanding its argument
+ can be used.
+
+18. It is now possible to use newline and other control characters (those with
+ values less than 32, plus DEL) as separators in lists.
+
+19. The exigrep utility now has a -v option, which inverts the matching
+ condition.
+
+20. The host_find_failed option in the manualroute router can now be set to
+ "ignore".
+
+
+Version 4.66
+------------
+
+No new features were added to 4.66.
+
+
+Version 4.65
+------------
+
+No new features were added to 4.65.
+
+
+Version 4.64
+------------
+
+ 1. ACL variables can now be given arbitrary names, as long as they start with
+ "acl_c" or "acl_m" (for connection variables and message variables), are at
+ least six characters long, with the sixth character being either a digit or
+ an underscore.
+
+ 2. There is a new ACL modifier called log_reject_target. It makes it possible
+ to specify which logs are used for messages about ACL rejections.
+
+ 3. There is a new authenticator called "dovecot". This is an interface to the
+ authentication facility of the Dovecot POP/IMAP server, which can support a
+ number of authentication methods.
+
+ 4. The variable $message_headers_raw provides a concatenation of all the
+ messages's headers without any decoding. This is in contrast to
+ $message_headers, which does RFC2047 decoding on the header contents.
+
+ 5. In a DNS black list, if two domain names, comma-separated, are given, the
+ second is used first to do an initial check, making use of any IP value
+ restrictions that are set. If there is a match, the first domain is used,
+ without any IP value restrictions, to get the TXT record.
+
+ 6. All authenticators now have a server_condition option.
+
+ 7. There is a new command-line option called -Mset. It is useful only in
+ conjunction with -be (that is, when testing string expansions). It must be
+ followed by a message id; Exim loads the given message from its spool
+ before doing the expansions.
+
+ 8. Another similar new command-line option is called -bem. It operates like
+ -be except that it must be followed by the name of a file that contains a
+ message.
+
+ 9. When an address is delayed because of a 4xx response to a RCPT command, it
+ is now the combination of sender and recipient that is delayed in
+ subsequent queue runs until its retry time is reached.
+
+10. Unary negation and the bitwise logical operators and, or, xor, not, and
+ shift, have been added to the eval: and eval10: expansion items.
+
+11. The variables $interface_address and $interface_port have been renamed
+ as $received_ip_address and $received_port, to make it clear that they
+ relate to message reception rather than delivery. (The old names remain
+ available for compatibility.)
+
+12. The "message" modifier can now be used on "accept" and "discard" acl verbs
+ to vary the message that is sent when an SMTP command is accepted.
+
+
+Version 4.63
------------
-The documentation is up-to-date for the 4.50 release.
+1. There is a new Boolean option called filter_prepend_home for the redirect
+ router.
+
+2. There is a new acl, set by acl_not_smtp_start, which is run right at the
+ start of receiving a non-SMTP message, before any of the message has been
+ read.
+
+3. When an SMTP error message is specified in a "message" modifier in an ACL,
+ or in a :fail: or :defer: message in a redirect router, Exim now checks the
+ start of the message for an SMTP error code.
+
+4. There is a new parameter for LDAP lookups called "referrals", which takes
+ one of the settings "follow" (the default) or "nofollow".
+
+5. Version 20070721.2 of exipick now included, offering these new options:
+ --reverse
+ After all other sorting options have bee processed, reverse order
+ before displaying messages (-R is synonym).
+ --random
+ Randomize order of matching messages before displaying.
+ --size
+ Instead of displaying the matching messages, display the sum
+ of their sizes.
+ --sort <variable>[,<variable>...]
+ Before displaying matching messages, sort the messages according to
+ each messages value for each variable.
+ --not
+ Negate the value for every test (returns inverse output from the
+ same criteria without --not).
+
+
+Version 4.62
+------------
+
+1. The ${readsocket expansion item now supports Internet domain sockets as well
+ as Unix domain sockets. If the first argument begins "inet:", it must be of
+ the form "inet:host:port". The port is mandatory; it may be a number or the
+ name of a TCP port in /etc/services. The host may be a name, or it may be an
+ IP address. An ip address may optionally be enclosed in square brackets.
+ This is best for IPv6 addresses. For example:
+
+ ${readsocket{inet:[::1]:1234}{<request data>}...
+
+ Only a single host name may be given, but if looking it up yield more than
+ one IP address, they are each tried in turn until a connection is made. Once
+ a connection has been made, the behaviour is as for ${readsocket with a Unix
+ domain socket.
+
+2. If a redirect router sets up file or pipe deliveries for more than one
+ incoming address, and the relevant transport has batch_max set greater than
+ one, a batch delivery now occurs.
+
+3. The appendfile transport has a new option called maildirfolder_create_regex.
+ Its value is a regular expression. For a maildir delivery, this is matched
+ against the maildir directory; if it matches, Exim ensures that a
+ maildirfolder file is created alongside the new, cur, and tmp directories.
+
+
+Version 4.61
+------------
+
+The documentation is up-to-date for the 4.61 release. Major new features since
+the 4.60 release are:
+
+. An option called disable_ipv6, to disable the use of IPv6 completely.
+
+. An increase in the number of ACL variables to 20 of each type.
+
+. A change to use $auth1, $auth2, and $auth3 in authenticators instead of $1,
+ $2, $3, (though those are still set) because the numeric variables get used
+ for other things in complicated expansions.
+
+. The default for rfc1413_query_timeout has been changed from 30s to 5s.
+
+. It is possible to use setclassresources() on some BSD OS to control the
+ resources used in pipe deliveries.
+
+. A new ACL modifier called add_header, which can be used with any verb.
+
+. More errors are detectable in retry rules.
+
+There are a number of other additions too.
+
+
+Version 4.60
+------------
+
+The documentation is up-to-date for the 4.60 release. Major new features since
+the 4.50 release are:
+
+. Support for SQLite.
+
+. Support for IGNOREQUOTA in LMTP.
+
+. Extensions to the "submission mode" features.
+
+. Support for Client SMTP Authorization (CSA).
+
+. Support for ratelimiting hosts and users.
+
+. New expansion items to help with the BATV "prvs" scheme.
+
+. A "match_ip" condition, that matches an IP address against a list.
+
+There are many more minor changes.
****
git://git.exim.org / users / heiko / exim.git / blobdiff