Added lib resolv to Darwin Makefile - hopefully not breaking older versions

[users/jgh/exim.git] / doc / doc-docbook / spec.xfpt

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 2b47f0512f26b257afc1f821b0bf15a7d1766066..6a671cd4211f2e7404875e63deb015912a437643 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -1,4 +1,4 @@
-. $Cambridge: exim/doc/doc-docbook/spec.xfpt,v 1.31 2008/01/29 17:08:54 fanf2 Exp $
+. $Cambridge: exim/doc/doc-docbook/spec.xfpt,v 1.66 2009/11/05 19:37:00 nm4 Exp $

 .
 . /////////////////////////////////////////////////////////////////////////////
 . This is the primary source of the Exim Manual. It is an xfpt document that is
 .
 . /////////////////////////////////////////////////////////////////////////////
 . This is the primary source of the Exim Manual. It is an xfpt document that is


@@ -172,17 +172,15 @@
 <bookinfo>
 <title>Specification of the Exim Mail Transfer Agent</title>
 <titleabbrev>The Exim MTA</titleabbrev>
 <bookinfo>
 <title>Specification of the Exim Mail Transfer Agent</title>
 <titleabbrev>The Exim MTA</titleabbrev>

-<date>23 August 2007</date>
-<author><firstname>Philip</firstname><surname>Hazel</surname></author>
-<authorinitials>PH</authorinitials>
-<affiliation><orgname>University of Cambridge Computing Service</orgname></affiliation>
-<address>New Museums Site, Pembroke Street, Cambridge CB2 3QH, England</address>
+<date>5 November 2009</date>
+<author><firstname>Exim</firstname><surname>Maintainers</surname></author>
+<authorinitials>EM</authorinitials>

 <revhistory><revision>
 <revhistory><revision>

-  <revnumber>4.68</revnumber>
-  <date>23 August 2007</date>
-  <authorinitials>PH</authorinitials>
+  <revnumber>4.70</revnumber>
+  <date>5 November 2009</date>
+  <authorinitials>EM</authorinitials>

 </revision></revhistory>
 </revision></revhistory>

-<copyright><year>2007</year><holder>University of Cambridge</holder></copyright>
+<copyright><year>2009</year><holder>University of Cambridge</holder></copyright>

 </bookinfo>
 .literal off
 
 </bookinfo>
 .literal off
 


@@ -367,6 +365,7 @@ contributors.
 
 
 .section "Exim documentation" "SECID1"
 
 
 .section "Exim documentation" "SECID1"

+. Keep this example change bar when updating the documentation!

 .new
 .cindex "documentation"
 This edition of the Exim specification applies to version &version; of Exim.
 .new
 .cindex "documentation"
 This edition of the Exim specification applies to version &version; of Exim.


@@ -430,8 +429,6 @@ directory are:
 .row &_exim.8_&              "a man page of Exim's command line options"
 .row &_experimental.txt_&    "documentation of experimental features"
 .row &_filter.txt_&          "specification of the filter language"
 .row &_exim.8_&              "a man page of Exim's command line options"
 .row &_experimental.txt_&    "documentation of experimental features"
 .row &_filter.txt_&          "specification of the filter language"

-.row &_pcrepattern.txt_&     "specification of PCRE regular expressions"
-.row &_pcretest.txt_&        "specification of the PCRE testing program"

 .row &_Exim3.upgrade_&       "upgrade notes from release 2 to release 3"
 .row &_Exim4.upgrade_&       "upgrade notes from release 3 to release 4"
 .endtable
 .row &_Exim3.upgrade_&       "upgrade notes from release 2 to release 3"
 .row &_Exim4.upgrade_&       "upgrade notes from release 3 to release 4"
 .endtable


@@ -456,12 +453,12 @@ Squared, formerly Planet Online Ltd, whose support I gratefully acknowledge.
 .cindex "FAQ"
 As well as Exim distribution tar files, the Exim web site contains a number of
 differently formatted versions of the documentation. A recent addition to the
 .cindex "FAQ"
 As well as Exim distribution tar files, the Exim web site contains a number of
 differently formatted versions of the documentation. A recent addition to the

-online information is the Exim wiki &new("(&url(http://wiki.exim.org))"),
+online information is the Exim wiki (&url(http://wiki.exim.org)),

 which contains what used to be a separate FAQ, as well as various other
 examples, tips, and know-how that have been contributed by Exim users.
 
 .cindex Bugzilla
 which contains what used to be a separate FAQ, as well as various other
 examples, tips, and know-how that have been contributed by Exim users.
 
 .cindex Bugzilla

-An Exim Bugzilla exists at &new("&url(http://bugs.exim.org)"). You can use
+An Exim Bugzilla exists at &url(http://bugs.exim.org). You can use

 this to report bugs, and also to add items to the wish list. Please search
 first to check that you are not duplicating a previous entry.
 
 this to report bugs, and also to add items to the wish list. Please search
 first to check that you are not duplicating a previous entry.
 


@@ -500,8 +497,8 @@ information will be posted at &url(http://www-tus.csx.cam.ac.uk/courses/exim/).
 .section "Bug reports" "SECID5"
 .cindex "bug reports"
 .cindex "reporting bugs"
 .section "Bug reports" "SECID5"
 .cindex "bug reports"
 .cindex "reporting bugs"

-Reports of obvious bugs &new("can be emailed to &'bugs@exim.org'& or reported
-via the Bugzilla (&url(http://bugs.exim.org)).") However, if you are unsure
+Reports of obvious bugs can be emailed to &'bugs@exim.org'& or reported
+via the Bugzilla (&url(http://bugs.exim.org)). However, if you are unsure

 whether some behaviour is a bug or not, the best thing to do is to post a
 message to the &'exim-dev'& mailing list and have it discussed.
 
 whether some behaviour is a bug or not, the best thing to do is to post a
 message to the &'exim-dev'& mailing list and have it discussed.
 


@@ -729,13 +726,14 @@ the Exim documentation, &"spool"& is always used in the first sense.
 A number of pieces of external code are included in the Exim distribution.
 
 .ilist
 A number of pieces of external code are included in the Exim distribution.
 
 .ilist

+.new

 Regular expressions are supported in the main Exim program and in the
 Exim monitor using the freely-distributable PCRE library, copyright
 Regular expressions are supported in the main Exim program and in the
 Exim monitor using the freely-distributable PCRE library, copyright

-&copy; University of Cambridge. The source to a cut down version of PCRE
-used to be distributed in the directory &_src/pcre_&. However, this is
-no longer the case and you will need to use a system PCRE library or
-obtain and install the full version of the library from
+&copy; University of Cambridge. The source to PCRE is no longer shipped with
+Exim, so you will need to use the version of PCRE shipped with your system,
+or obtain and install the full version of the library from

 &url(ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre).
 &url(ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre).

+.wen

 .next
 .cindex "cdb" "acknowledgment"
 Support for the cdb (Constant DataBase) lookup method is provided by code
 .next
 .cindex "cdb" "acknowledgment"
 Support for the cdb (Constant DataBase) lookup method is provided by code


@@ -1654,7 +1652,7 @@ architecture and operating system for itself, but the defaults can be
 overridden if necessary.
 
 
 overridden if necessary.
 
 

-.section "PCRE library" "SECTdb"
+.section "PCRE library" "SECTpcre"

 .cindex "PCRE library"
 Exim no longer has an embedded PCRE library as the vast majority of
 modern systems include PCRE as a system library, although you may need
 .cindex "PCRE library"
 Exim no longer has an embedded PCRE library as the vast majority of
 modern systems include PCRE as a system library, although you may need


@@ -2223,13 +2221,14 @@ configuration. (If a default alias file is created, its name &'is'& modified.)
 For backwards compatibility, ROOT is used if DESTDIR is not set,
 but this usage is deprecated.
 
 For backwards compatibility, ROOT is used if DESTDIR is not set,
 but this usage is deprecated.
 

+.new

 .cindex "installing Exim" "what is not installed"
 Running &'make install'& does not copy the Exim 4 conversion script
 .cindex "installing Exim" "what is not installed"
 Running &'make install'& does not copy the Exim 4 conversion script

-&'convert4r4'&, or the &'pcretest'& test program. You will probably run the
-first of these only once (if you are upgrading from Exim 3), and the second
-isn't really part of Exim. None of the documentation files in the &_doc_&
+&'convert4r4'&. You will probably run this only once if you are
+upgrading from Exim 3. None of the documentation files in the &_doc_&

 directory are copied, except for the info files when you have set
 INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.
 directory are copied, except for the info files when you have set
 INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.

+.wen

 
 For the utility programs, old versions are renamed by adding the suffix &_.O_&
 to their names. The Exim binary itself, however, is handled differently. It is
 
 For the utility programs, old versions are renamed by adding the suffix &_.O_&
 to their names. The Exim binary itself, however, is handled differently. It is


@@ -2978,6 +2977,7 @@ local part) and outputs what it finds.
 
 .cindex "options" "router &-- extracting"
 .cindex "options" "transport &-- extracting"
 
 .cindex "options" "router &-- extracting"
 .cindex "options" "transport &-- extracting"

+.cindex "options" "authenticator &-- extracting"

 If one of the words &%router%&, &%transport%&, or &%authenticator%& is given,
 followed by the name of an appropriate driver instance, the option settings for
 that driver are output. For example:
 If one of the words &%router%&, &%transport%&, or &%authenticator%& is given,
 followed by the name of an appropriate driver instance, the option settings for
 that driver are output. For example:


@@ -2991,6 +2991,13 @@ using one of the words &%router_list%&, &%transport_list%&, or
 settings can be obtained by using &%routers%&, &%transports%&, or
 &%authenticators%&.
 
 settings can be obtained by using &%routers%&, &%transports%&, or
 &%authenticators%&.
 

+.new
+.cindex "options" "macro &-- extracting"
+If invoked by an admin user, then &%macro%&, &%macro_list%& and &%macros%&
+are available, similarly to the drivers.  Because macros are sometimes used
+for storing passwords, this option is restricted.
+The output format is one item per line.
+.wen

 
 .vitem &%-bp%&
 .oindex "&%-bp%&"
 
 .vitem &%-bp%&
 .oindex "&%-bp%&"


@@ -4721,7 +4728,7 @@ up in a MySQL database. It helps to keep the file less cluttered if long
 strings such as SQL statements are defined separately as macros, for example:
 .code
 ALIAS_QUERY = select mailbox from user where \
 strings such as SQL statements are defined separately as macros, for example:
 .code
 ALIAS_QUERY = select mailbox from user where \

-              login=${quote_mysql:$local_part};
+              login='${quote_mysql:$local_part}';

 .endd
 This can then be used in a &(redirect)& router setting like this:
 .code
 .endd
 This can then be used in a &(redirect)& router setting like this:
 .code


@@ -5888,6 +5895,12 @@ password are correct. In the examples it just produces an error message.
 To make the authenticators work, you can use a string expansion
 expression like one of the examples in &<<CHAPplaintext>>&.
 
 To make the authenticators work, you can use a string expansion
 expression like one of the examples in &<<CHAPplaintext>>&.
 

+.new
+Beware that the sequence of the parameters to PLAIN and LOGIN differ; the
+usercode and password are in different positions.  &<<CHAPplaintext>>&
+covers both.
+.wen
+

 .ecindex IIDconfiwal
 
 
 .ecindex IIDconfiwal
 
 


@@ -5906,14 +5919,14 @@ regular expressions is discussed in many Perl reference books, and also in
 Jeffrey Friedl's &'Mastering Regular Expressions'&, which is published by
 O'Reilly (see &url(http://www.oreilly.com/catalog/regex2/)).
 
 Jeffrey Friedl's &'Mastering Regular Expressions'&, which is published by
 O'Reilly (see &url(http://www.oreilly.com/catalog/regex2/)).
 

+.new

 The documentation for the syntax and semantics of the regular expressions that
 The documentation for the syntax and semantics of the regular expressions that

-are supported by PCRE is included in plain text in the file
-&_doc/pcrepattern.txt_& in the Exim distribution, and also in the HTML
-tarbundle of Exim documentation. It describes in detail the features of the
-regular expressions that PCRE supports, so no further description is included
-here. The PCRE functions are called from Exim using the default option settings
-(that is, with no PCRE options set), except that the PCRE_CASELESS option is
-set when the matching is required to be case-insensitive.
+are supported by PCRE is included in the PCRE distribution, and no further
+description is included here. The PCRE functions are called from Exim using
+the default option settings (that is, with no PCRE options set), except that
+the PCRE_CASELESS option is set when the matching is required to be
+case-insensitive.
+.wen

 
 In most cases, when a regular expression is required in an Exim configuration,
 it has to start with a circumflex, in order to distinguish it from plain text
 
 In most cases, when a regular expression is required in an Exim configuration,
 it has to start with a circumflex, in order to distinguish it from plain text


@@ -5952,47 +5965,6 @@ $ is needed because string expansion also interprets dollar characters.
 
 
 
 
 
 

-.section "Testing regular expressions" "SECID59"
-.cindex "testing" "regular expressions"
-.cindex "regular expressions" "testing"
-.cindex "&'pcretest'&"
-A program called &'pcretest'& forms part of the PCRE distribution and is built
-with PCRE during the process of building Exim. It is primarily intended for
-testing PCRE itself, but it can also be used for experimenting with regular
-expressions. After building Exim, the binary can be found in the build
-directory (it is not installed anywhere automatically). There is documentation
-of various options in &_doc/pcretest.txt_&, but for simple testing, none are
-needed. This is the output of a sample run of &'pcretest'&:
-.display
-&`  re> `&&*&`/^([@]+)@.+\.(ac|edu)\.(?!kr)[a-z]{2}$/`&*&
-&`data> `&&*&`x@y.ac.uk`&*&
-&` 0: x@y.ac.uk`&
-&` 1: x`&
-&` 2: ac`&
-&`data> `&&*&`x@y.ac.kr`&*&
-&`No match`&
-&`data> `&&*&`x@y.edu.com`&*&
-&`No match`&
-&`data> `&&*&`x@y.edu.co`&*&
-&` 0: x@y.edu.co`&
-&` 1: x`&
-&` 2: edu`&
-.endd
-Input typed by the user is shown in bold face. After the &"re>"& prompt, a
-regular expression enclosed in delimiters is expected. If this compiles without
-error, &"data>"& prompts are given for strings against which the expression is
-matched. An empty data line causes a new regular expression to be read. If the
-match is successful, the captured substring values (that is, what would be in
-the variables &$0$&, &$1$&, &$2$&, etc.) are shown. The above example tests for
-an email address whose domain ends with either &"ac"& or &"edu"& followed by a
-two-character top-level domain that is not &"kr"&. The local part is captured
-in &$1$& and the &"ac"& or &"edu"& in &$2$&.
-
-
-
-
-
-

 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 


@@ -6174,7 +6146,7 @@ IPv6 addresses must be enclosed in quotes to prevent the first internal colon
 being interpreted as a key terminator. For example:
 .code
 1.2.3.4:           data for 1.2.3.4
 being interpreted as a key terminator. For example:
 .code
 1.2.3.4:           data for 1.2.3.4

-192.168.0.0/16     data for 192.168.0.0/16
+192.168.0.0/16:    data for 192.168.0.0/16

 "abcd::cdab":      data for abcd::cdab
 "abcd:abcd::/32"   data for abcd:abcd::/32
 .endd
 "abcd::cdab":      data for abcd::cdab
 "abcd:abcd::/32"   data for abcd:abcd::/32
 .endd


@@ -7156,9 +7128,9 @@ If any MySQL, PostgreSQL, Oracle, or InterBase lookups are used, the
 &%mysql_servers%&, &%pgsql_servers%&, &%oracle_servers%&, or &%ibase_servers%&
 option (as appropriate) must be set to a colon-separated list of server
 information.
 &%mysql_servers%&, &%pgsql_servers%&, &%oracle_servers%&, or &%ibase_servers%&
 option (as appropriate) must be set to a colon-separated list of server
 information.

-&new("(For MySQL and PostgreSQL only, the global option need not be set if all
+(For MySQL and PostgreSQL only, the global option need not be set if all

 queries contain their own server information &-- see section
 queries contain their own server information &-- see section

-&<<SECTspeserque>>&.)") Each item in the list is a slash-separated list of four
+&<<SECTspeserque>>&.) Each item in the list is a slash-separated list of four

 items: host name, database name, user name, and password. In the case of
 Oracle, the host name field is used for the &"service name"&, and the database
 name field is not used and should be empty. For example:
 items: host name, database name, user name, and password. In the case of
 Oracle, the host name field is used for the &"service name"&, and the database
 name field is not used and should be empty. For example:


@@ -7218,13 +7190,13 @@ mysql_servers = slave1/db/name/pw:\
 .endd
 In an updating lookup, you could then write:
 .code
 .endd
 In an updating lookup, you could then write:
 .code

-${lookup mysql{servers=master; UPDATE ...}
+${lookup mysql{servers=master; UPDATE ...} }

 .endd
 That query would then be sent only to the master server. If, on the other hand,
 the master is not to be used for reading, and so is not present in the global
 option, you can still update it by a query of this form:
 .code
 .endd
 That query would then be sent only to the master server. If, on the other hand,
 the master is not to be used for reading, and so is not present in the global
 option, you can still update it by a query of this form:
 .code

-${lookup pgsql{servers=master/db/name/pw; UPDATE ...}
+${lookup pgsql{servers=master/db/name/pw; UPDATE ...} }

 .endd
 
 
 .endd
 
 


@@ -9778,6 +9750,24 @@ lower case), signifying multiplication by 1024 or 1024*1024, respectively.
 As a special case, the numerical value of an empty string is taken as
 zero.
 
 As a special case, the numerical value of an empty string is taken as
 zero.
 

+.new
+.vitem &*bool&~{*&<&'string'&>&*}*&
+.cindex "expansion" "boolean parsing"
+.cindex "&%bool%& expansion condition"
+This condition turns a string holding a true or false representation into
+a boolean state.  It parses &"true"&, &"false"&, &"yes"& and &"no"&
+(case-insensitively); also positive integer numbers map to true if non-zero,
+false if zero.  Leading whitespace is ignored.
+All other string values will result in expansion failure.
+
+When combined with ACL variables, this expansion condition will let you
+make decisions in one place and act on those decisions in another place.
+For example,
+.code
+${if bool{$acl_m_privileged_sender} ...
+.endd
+.wen
+

 .vitem &*crypteq&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*&
 .cindex "expansion" "encrypted comparison"
 .cindex "encrypted strings, comparing"
 .vitem &*crypteq&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*&
 .cindex "expansion" "encrypted comparison"
 .cindex "encrypted strings, comparing"


@@ -10229,6 +10219,12 @@ configuration, you might have this:
 .code
 server_condition = ${if pwcheck{$auth1:$auth2}}
 .endd
 .code
 server_condition = ${if pwcheck{$auth1:$auth2}}
 .endd

+.new
+Again, for a PLAIN authenticator configuration, this would be:
+.code
+server_condition = ${if pwcheck{$auth2:$auth3}}
+.endd
+.wen

 .vitem &*queue_running*&
 .cindex "queue runner" "detecting when delivering from"
 .cindex "expansion" "queue runner test"
 .vitem &*queue_running*&
 .cindex "queue runner" "detecting when delivering from"
 .cindex "expansion" "queue runner test"


@@ -10762,7 +10758,7 @@ This is an obsolete name for &$received_port$&.
 .vitem &$item$&
 .vindex "&$item$&"
 This variable is used during the expansion of &*forall*& and &*forany*&
 .vitem &$item$&
 .vindex "&$item$&"
 This variable is used during the expansion of &*forall*& and &*forany*&

-conditions (see section &<<SECTexpcond>>&), and &*filter*&, &*man*&, and
+conditions (see section &<<SECTexpcond>>&), and &*filter*&, &*map*&, and

 &*reduce*& items (see section &<<SECTexpcond>>&). In other circumstances, it is
 empty.
 
 &*reduce*& items (see section &<<SECTexpcond>>&). In other circumstances, it is
 empty.
 


@@ -11015,10 +11011,12 @@ doing a delivery in maildir format, the value of &$message_size$& is the
 precise size of the file that has been written. See also
 &$message_body_size$&, &$body_linecount$&, and &$body_zerocount$&.
 
 precise size of the file that has been written. See also
 &$message_body_size$&, &$body_linecount$&, and &$body_zerocount$&.
 

+.new

 .cindex "RCPT" "value of &$message_size$&"
 .cindex "RCPT" "value of &$message_size$&"

-While running an ACL at the time of an SMTP RCPT command, &$message_size$&
+While running a per message ACL (mail/rcpt/predata), &$message_size$&

 contains the size supplied on the MAIL command, or -1 if no size was given. The
 value may not, of course, be truthful.
 contains the size supplied on the MAIL command, or -1 if no size was given. The
 value may not, of course, be truthful.

+.wen

 
 .vitem &$mime_$&&'xxx'&
 A number of variables whose names start with &$mime$& are
 
 .vitem &$mime_$&&'xxx'&
 A number of variables whose names start with &$mime$& are


@@ -11641,9 +11639,9 @@ details of the &(smtp)& transport.
 When a message is received from a remote host over an encrypted SMTP
 connection, and Exim is configured to request a certificate from the client,
 the value of the Distinguished Name of the certificate is made available in the
 When a message is received from a remote host over an encrypted SMTP
 connection, and Exim is configured to request a certificate from the client,
 the value of the Distinguished Name of the certificate is made available in the

-&$tls_peerdn$& during subsequent processing. &new("Like &$tls_cipher$&, the
+&$tls_peerdn$& during subsequent processing. Like &$tls_cipher$&, the

 value is retained during message delivery, except during outbound SMTP
 value is retained during message delivery, except during outbound SMTP

-deliveries.")
+deliveries.

 
 .vitem &$tod_bsdinbox$&
 .vindex "&$tod_bsdinbox$&"
 
 .vitem &$tod_bsdinbox$&
 .vindex "&$tod_bsdinbox$&"


@@ -12186,7 +12184,7 @@ listed in more than one group.
 .row &%disable_ipv6%&                "do no IPv6 processing"
 .row &%keep_malformed%&              "for broken files &-- should not happen"
 .row &%localhost_number%&            "for unique message ids in clusters"
 .row &%disable_ipv6%&                "do no IPv6 processing"
 .row &%keep_malformed%&              "for broken files &-- should not happen"
 .row &%localhost_number%&            "for unique message ids in clusters"

-.row &new(&%message_body_newlines%&) "retain newlines in &$message_body$&"
+.row &%message_body_newlines%&       "retain newlines in &$message_body$&"

 .row &%message_body_visible%&        "how much to show in &$message_body$&"
 .row &%mua_wrapper%&                 "run in &""MUA wrapper""& mode"
 .row &%print_topbitchars%&           "top-bit characters are printing"
 .row &%message_body_visible%&        "how much to show in &$message_body$&"
 .row &%mua_wrapper%&                 "run in &""MUA wrapper""& mode"
 .row &%print_topbitchars%&           "top-bit characters are printing"


@@ -12253,13 +12251,13 @@ listed in more than one group.
 
 .section "Data lookups" "SECID101"
 .table2
 
 .section "Data lookups" "SECID101"
 .table2

-.row &new(&%ibase_servers%&)         "InterBase servers"
+.row &%ibase_servers%&               "InterBase servers"

 .row &%ldap_default_servers%&        "used if no server in query"
 .row &%ldap_version%&                "set protocol version"
 .row &%lookup_open_max%&             "lookup files held open"
 .row &%ldap_default_servers%&        "used if no server in query"
 .row &%ldap_version%&                "set protocol version"
 .row &%lookup_open_max%&             "lookup files held open"

-.row &new(&%mysql_servers%&)               "default MySQL servers"
-.row &new(&%oracle_servers%&)              "Oracle servers"
-.row &new(&%pgsql_servers%&)               "default PostgreSQL servers"
+.row &%mysql_servers%&               "default MySQL servers"
+.row &%oracle_servers%&              "Oracle servers"
+.row &%pgsql_servers%&               "default PostgreSQL servers"

 .row &%sqlite_lock_timeout%&         "as it says"
 .endtable
 
 .row &%sqlite_lock_timeout%&         "as it says"
 .endtable
 


@@ -12302,7 +12300,7 @@ listed in more than one group.
 .row &%check_spool_space%&           "before accepting a message"
 .row &%deliver_queue_load_max%&      "no queue deliveries if load high"
 .row &%queue_only_load%&             "queue incoming if load high"
 .row &%check_spool_space%&           "before accepting a message"
 .row &%deliver_queue_load_max%&      "no queue deliveries if load high"
 .row &%queue_only_load%&             "queue incoming if load high"

-.row &new(&%queue_only_load_latch%&) "don't re-evaluate load for each message"
+.row &%queue_only_load_latch%&       "don't re-evaluate load for each message"

 .row &%queue_run_max%&               "maximum simultaneous queue runners"
 .row &%remote_max_parallel%&         "parallel SMTP delivery per message"
 .row &%smtp_accept_max%&             "simultaneous incoming connections"
 .row &%queue_run_max%&               "maximum simultaneous queue runners"
 .row &%remote_max_parallel%&         "parallel SMTP delivery per message"
 .row &%smtp_accept_max%&             "simultaneous incoming connections"


@@ -12384,6 +12382,7 @@ listed in more than one group.
 .row &%gnutls_require_kx%&           "control GnuTLS key exchanges"
 .row &%gnutls_require_mac%&          "control GnuTLS MAC algorithms"
 .row &%gnutls_require_protocols%&    "control GnuTLS protocols"
 .row &%gnutls_require_kx%&           "control GnuTLS key exchanges"
 .row &%gnutls_require_mac%&          "control GnuTLS MAC algorithms"
 .row &%gnutls_require_protocols%&    "control GnuTLS protocols"

+.row &%gnutls_compat_mode%&          "use GnuTLS compatibility mode"

 .row &%tls_advertise_hosts%&         "advertise TLS to these hosts"
 .row &%tls_certificate%&             "location of server certificate"
 .row &%tls_crl%&                     "certificate revocation list"
 .row &%tls_advertise_hosts%&         "advertise TLS to these hosts"
 .row &%tls_certificate%&             "location of server certificate"
 .row &%tls_crl%&                     "certificate revocation list"


@@ -12537,7 +12536,7 @@ See also the &'Policy controls'& section above.
 .row &%queue_only%&                  "no immediate delivery at all"
 .row &%queue_only_file%&             "no immediate delivery if file exists"
 .row &%queue_only_load%&             "no immediate delivery if load is high"
 .row &%queue_only%&                  "no immediate delivery at all"
 .row &%queue_only_file%&             "no immediate delivery if file exists"
 .row &%queue_only_load%&             "no immediate delivery if load is high"

-.row &new(&%queue_only_load_latch%&) "don't re-evaluate load for each message"
+.row &%queue_only_load_latch%&       "don't re-evaluate load for each message"

 .row &%queue_only_override%&         "allow command line to override"
 .row &%queue_run_in_order%&          "order of arrival"
 .row &%queue_run_max%&               "of simultaneous queue runners"
 .row &%queue_only_override%&         "allow command line to override"
 .row &%queue_run_in_order%&          "order of arrival"
 .row &%queue_run_max%&               "of simultaneous queue runners"


@@ -13118,7 +13117,7 @@ dns_check_names_pattern = \
   (?i)^(?>(?(1)\.|())[^\W_](?>[a-z0-9/-]*[^\W_])?)+$
 .endd
 which permits only letters, digits, slashes, and hyphens in components, but
   (?i)^(?>(?(1)\.|())[^\W_](?>[a-z0-9/-]*[^\W_])?)+$
 .endd
 which permits only letters, digits, slashes, and hyphens in components, but

-they must start and end with a letter or digit. &new(Slashes) are not, in fact,
+they must start and end with a letter or digit. Slashes are not, in fact,

 permitted in host names, but they are found in certain NS records (which can be
 accessed in Exim by using a &%dnsdb%& lookup). If you set
 &%allow_utf8_domains%&, you must modify this pattern, or set the option to an
 permitted in host names, but they are found in certain NS records (which can be
 accessed in Exim by using a &%dnsdb%& lookup). If you set
 &%allow_utf8_domains%&, you must modify this pattern, or set the option to an


@@ -13383,6 +13382,12 @@ server. For details, see section &<<SECTreqciphgnu>>&.
 This option controls the protocols when GnuTLS is used in an Exim
 server. For details, see section &<<SECTreqciphgnu>>&.
 
 This option controls the protocols when GnuTLS is used in an Exim
 server. For details, see section &<<SECTreqciphgnu>>&.
 

+.new
+.option gnutls_compat_mode main boolean unset
+This option controls whether GnuTLS is used in compatibility mode in an Exim
+server. This reduces security slightly, but improves interworking with older
+implementations of TLS.
+.wen

 
 .option headers_charset main string "see below"
 This option sets a default character set for translating from encoded MIME
 
 .option headers_charset main string "see below"
 This option sets a default character set for translating from encoded MIME


@@ -13454,10 +13459,10 @@ do.
 By default, Exim just checks the syntax of HELO and EHLO commands (see
 &%helo_accept_junk_hosts%& and &%helo_allow_chars%&). However, some sites like
 to do more extensive checking of the data supplied by these commands. The ACL
 By default, Exim just checks the syntax of HELO and EHLO commands (see
 &%helo_accept_junk_hosts%& and &%helo_allow_chars%&). However, some sites like
 to do more extensive checking of the data supplied by these commands. The ACL

-condition &`verify`& &`=`& &`helo`& is provided to make this possible.
+condition &`verify = helo`& is provided to make this possible.

 Formerly, it was necessary also to set this option (&%helo_try_verify_hosts%&)
 to force the check to occur. From release 4.53 onwards, this is no longer
 Formerly, it was necessary also to set this option (&%helo_try_verify_hosts%&)
 to force the check to occur. From release 4.53 onwards, this is no longer

-necessary. If the check has not been done before &`verify`& &`=`& &`helo`& is
+necessary. If the check has not been done before &`verify = helo`& is

 encountered, it is done at that time. Consequently, this option is obsolete.
 Its specification is retained here for backwards compatibility.
 
 encountered, it is done at that time. Consequently, this option is obsolete.
 Its specification is retained here for backwards compatibility.
 


@@ -13479,7 +13484,7 @@ available) yields the calling host address.
 
 However, the EHLO or HELO command is not rejected if any of the checks
 fail. Processing continues, but the result of the check is remembered, and can
 
 However, the EHLO or HELO command is not rejected if any of the checks
 fail. Processing continues, but the result of the check is remembered, and can

-be detected later in an ACL by the &`verify`& &`=`& &`helo`& condition.
+be detected later in an ACL by the &`verify = helo`& condition.

 
 .option helo_verify_hosts main "host list&!!" unset
 .cindex "HELO verifying" "mandatory"
 
 .option helo_verify_hosts main "host list&!!" unset
 .cindex "HELO verifying" "mandatory"


@@ -13535,8 +13540,8 @@ this check fails, Exim behaves as if the name lookup failed.
 .vindex "&$sender_host_name$&"
 After any kind of failure, the host name (in &$sender_host_name$&) remains
 unset, and &$host_lookup_failed$& is set to the string &"1"&. See also
 .vindex "&$sender_host_name$&"
 After any kind of failure, the host name (in &$sender_host_name$&) remains
 unset, and &$host_lookup_failed$& is set to the string &"1"&. See also

-&%dns_again_means_nonexist%&, &%helo_lookup_domains%&, and &`verify`& &`=`&
-&`reverse_host_lookup`& in ACLs.
+&%dns_again_means_nonexist%&, &%helo_lookup_domains%&, and
+&`verify = reverse_host_lookup`& in ACLs.

 
 
 .option host_lookup_order main "string list" &`bydns:byaddr`&
 
 
 .option host_lookup_order main "string list" &`bydns:byaddr`&


@@ -17856,10 +17861,12 @@ redirection items of the form
 :defer:
 :fail:
 .endd
 :defer:
 :fail:
 .endd

-respectively. When a redirection list contains such an item, it applies to the
-entire redirection; any other items in the list are ignored (&':blackhole:'& is
-different). Any text following &':fail:'& or &':defer:'& is placed in the error
-text associated with the failure. For example, an alias file might contain:
+.new
+respectively. When a redirection list contains such an item, it applies
+to the entire redirection; any other items in the list are ignored. Any
+text following &':fail:'& or &':defer:'& is placed in the error text
+associated with the failure. For example, an alias file might contain:
+.wen

 .code
 X.Employee:  :fail: Gone away, no forwarding address
 .endd
 .code
 X.Employee:  :fail: Gone away, no forwarding address
 .endd


@@ -19003,12 +19010,12 @@ destination. The process that writes the message to the filter, the
 filter itself, and the original process that reads the result and delivers it
 are all run in parallel, like a shell pipeline.
 
 filter itself, and the original process that reads the result and delivers it
 are all run in parallel, like a shell pipeline.
 

+.new

 The filter can perform any transformations it likes, but of course should take
 The filter can perform any transformations it likes, but of course should take

-care not to break RFC 2822 syntax. A demonstration Perl script is provided in
-&_util/transport-filter.pl_&; this makes a few arbitrary modifications just to
-show the possibilities. Exim does not check the result, except to test for a
-final newline when SMTP is in use. All messages transmitted over SMTP must end
-with a newline, so Exim supplies one if it is missing.
+care not to break RFC 2822 syntax. Exim does not check the result, except to
+test for a final newline when SMTP is in use. All messages transmitted over
+SMTP must end with a newline, so Exim supplies one if it is missing.
+.wen

 
 .cindex "content scanning" "per user"
 A transport filter can be used to provide content-scanning on a per-user basis
 
 .cindex "content scanning" "per user"
 A transport filter can be used to provide content-scanning on a per-user basis


@@ -20651,8 +20658,8 @@ delivers the message to it using the LMTP protocol.
 
 .option timeout lmtp time 5m
 The transport is aborted if the created process or Unix domain socket does not
 
 .option timeout lmtp time 5m
 The transport is aborted if the created process or Unix domain socket does not

-respond to LMTP commands or message input within this timeout. &new("Delivery
-is deferred, and will be tried again later.") Here is an example of a typical
+respond to LMTP commands or message input within this timeout. Delivery
+is deferred, and will be tried again later. Here is an example of a typical

 LMTP transport:
 .code
 lmtp:
 LMTP transport:
 .code
 lmtp:


@@ -21485,6 +21492,13 @@ client. For details, see section &<<SECTreqciphgnu>>&.
 This option controls the protocols when GnuTLS is used in an Exim
 client. For details, see section &<<SECTreqciphgnu>>&.
 
 This option controls the protocols when GnuTLS is used in an Exim
 client. For details, see section &<<SECTreqciphgnu>>&.
 

+.new
+.option gnutls_compat_mode main boolean unset
+This option controls whether GnuTLS is used in compatibility mode in an Exim
+server. This reduces security slightly, but improves interworking with older
+implementations of TLS.
+.wen
+

 .option helo_data smtp string&!! "see below"
 .cindex "HELO" "argument, setting"
 .cindex "EHLO" "argument, setting"
 .option helo_data smtp string&!! "see below"
 .cindex "HELO" "argument, setting"
 .cindex "EHLO" "argument, setting"


@@ -21655,8 +21669,8 @@ unauthenticated. See also &%hosts_require_auth%&, and chapter
 .vindex "&$host$&"
 .vindex "&$host_address$&"
 This option specifies which interface to bind to when making an outgoing SMTP
 .vindex "&$host$&"
 .vindex "&$host_address$&"
 This option specifies which interface to bind to when making an outgoing SMTP

-call. &new("The value is an IP address, not an interface name such as
-&`eth0`&.") Do not confuse this with the interface address that was used when a
+call. The value is an IP address, not an interface name such as
+&`eth0`&. Do not confuse this with the interface address that was used when a

 message was received, which is in &$received_ip_address$&, formerly known as
 &$interface_address$&. The name was changed to minimize confusion with the
 outgoing interface address. There is no variable that contains an outgoing
 message was received, which is in &$received_ip_address$&, formerly known as
 &$interface_address$&. The name was changed to minimize confusion with the
 outgoing interface address. There is no variable that contains an outgoing


@@ -22282,11 +22296,9 @@ rewriting rule is skipped unless the relevant addresses are being processed.
 &`s`&       rewrite the &'Sender:'& header
 &`t`&       rewrite the &'To:'& header
 .endd
 &`s`&       rewrite the &'Sender:'& header
 &`t`&       rewrite the &'To:'& header
 .endd

-.new

 "All headers" means all of the headers listed above that can be selected
 individually, plus their &'Resent-'& versions. It does not include
 other headers such as &'Subject:'& etc.
 "All headers" means all of the headers listed above that can be selected
 individually, plus their &'Resent-'& versions. It does not include
 other headers such as &'Subject:'& etc.

-.wen

 
 You should be particularly careful about rewriting &'Sender:'& headers, and
 restrict this to special known cases in your own domains.
 
 You should be particularly careful about rewriting &'Sender:'& headers, and
 restrict this to special known cases in your own domains.


@@ -23572,18 +23584,22 @@ login:
   driver = plaintext
   public_name = LOGIN
   server_prompts = Username:: : Password::
   driver = plaintext
   public_name = LOGIN
   server_prompts = Username:: : Password::

-  server_condition = ${if ldapauth \
-    {user="cn=${quote_ldap_dn:$auth1},ou=people,o=example.org" \
-    pass=${quote:$auth2} \
-    ldap://ldap.example.org/}}
+  server_condition = ${if and{{
+    !eq{}{$auth1} }{ \
+    ldapauth{user="cn=${quote_ldap_dn:$auth1},ou=people,o=example.org" \
+             pass=${quote:$auth2} \
+             ldap://ldap.example.org/} }} }

   server_set_id = uid=$auth1,ou=people,o=example.org
 .endd
   server_set_id = uid=$auth1,ou=people,o=example.org
 .endd

-Note the use of the &%quote_ldap_dn%& operator to correctly quote the DN for
-authentication. However, the basic &%quote%& operator, rather than any of the
-LDAP quoting operators, is the correct one to use for the password, because
-quoting is needed only to make the password conform to the Exim syntax. At the
-LDAP level, the password is an uninterpreted string.
-
+.new
+We have to check that the username is not empty before using it, because LDAP
+does not permit empty DN components. We must also use the &%quote_ldap_dn%&
+operator to correctly quote the DN for authentication. However, the basic
+&%quote%& operator, rather than any of the LDAP quoting operators, is the
+correct one to use for the password, because quoting is needed only to make
+the password conform to the Exim syntax. At the LDAP level, the password is an
+uninterpreted string.
+.wen

 
 
 .section "Support for different kinds of authentication" "SECID174"
 
 
 .section "Support for different kinds of authentication" "SECID174"


@@ -23844,7 +23860,7 @@ sasl_cram_md5:
 sasl_plain:
   driver = cyrus_sasl
   public_name = PLAIN
 sasl_plain:
   driver = cyrus_sasl
   public_name = PLAIN

-  server_set_id = $auth1
+  server_set_id = $auth2

 .endd
 Cyrus SASL does implement the LOGIN authentication method, even though it is
 not a standard method. It is disabled by default in the source distribution,
 .endd
 Cyrus SASL does implement the LOGIN authentication method, even though it is
 not a standard method. It is disabled by default in the source distribution,


@@ -23877,7 +23893,7 @@ dovecot_plain:
   driver = dovecot
   public_name = PLAIN
   server_socket = /var/run/dovecot/auth-client
   driver = dovecot
   public_name = PLAIN
   server_socket = /var/run/dovecot/auth-client

-  server_set_id = $auth1
+  server_set_id = $auth2

 
 dovecot_ntlm:
   driver = dovecot
 
 dovecot_ntlm:
   driver = dovecot


@@ -24102,11 +24118,11 @@ sections &<<SECTreqciphssl>>& and &<<SECTreqciphgnu>>&.
 
 
 .section "GnuTLS parameter computation" "SECID181"
 
 
 .section "GnuTLS parameter computation" "SECID181"

-GnuTLS uses RSA and D-H parameters that may take a substantial amount of time
+GnuTLS uses D-H parameters that may take a substantial amount of time

 to compute. It is unreasonable to re-compute them for every TLS session.
 Therefore, Exim keeps this data in a file in its spool directory, called
 &_gnutls-params_&. The file is owned by the Exim user and is readable only by
 to compute. It is unreasonable to re-compute them for every TLS session.
 Therefore, Exim keeps this data in a file in its spool directory, called
 &_gnutls-params_&. The file is owned by the Exim user and is readable only by

-its owner. Every Exim process that start up GnuTLS reads the RSA and D-H
+its owner. Every Exim process that start up GnuTLS reads the D-H

 parameters from this file. If the file does not exist, the first Exim process
 that needs it computes the data and writes it to a temporary file which is
 renamed once it is complete. It does not matter if several Exim processes do
 parameters from this file. If the file does not exist, the first Exim process
 that needs it computes the data and writes it to a temporary file which is
 renamed once it is complete. It does not matter if several Exim processes do


@@ -24351,8 +24367,8 @@ incoming message (by default &-- you can, of course, change this), and it is
 also included in the log line that records a message's arrival, keyed by
 &"X="&, unless the &%tls_cipher%& log selector is turned off. The &%encrypted%&
 condition can be used to test for specific cipher suites in ACLs.
 also included in the log line that records a message's arrival, keyed by
 &"X="&, unless the &%tls_cipher%& log selector is turned off. The &%encrypted%&
 condition can be used to test for specific cipher suites in ACLs.

-&new("(For outgoing SMTP deliveries, &$tls_cipher$& is reset &-- see section
-&<<SECID185>>&.)")
+(For outgoing SMTP deliveries, &$tls_cipher$& is reset &-- see section
+&<<SECID185>>&.)

 
 Once TLS has been established, the ACLs that run for subsequent SMTP commands
 can check the name of the cipher suite and vary their actions accordingly. The
 
 Once TLS has been established, the ACLs that run for subsequent SMTP commands
 can check the name of the cipher suite and vary their actions accordingly. The


@@ -24460,13 +24476,10 @@ unencrypted.
 The &%tls_certificate%& and &%tls_privatekey%& options of the &(smtp)&
 transport provide the client with a certificate, which is passed to the server
 if it requests it. If the server is Exim, it will request a certificate only if
 The &%tls_certificate%& and &%tls_privatekey%& options of the &(smtp)&
 transport provide the client with a certificate, which is passed to the server
 if it requests it. If the server is Exim, it will request a certificate only if

-&%tls_verify_hosts%& or &%tls_try_verify_hosts%& matches the client. &*Note*&:
-These options must be set in the &(smtp)& transport for Exim to use TLS when it
-is operating as a client. Exim does not assume that a server certificate (set
-by the global options of the same name) should also be used when operating as a
-client.
+&%tls_verify_hosts%& or &%tls_try_verify_hosts%& matches the client.

 
 

-If &%tls_verify_certificates%& is set, it must name a file or,
+If the &%tls_verify_certificates%& option is set on the &(smtp)& transport, it
+must name a file or,

 for OpenSSL only (not GnuTLS), a directory, that contains a collection of
 expected server certificates. The client verifies the server's certificate
 against this collection, taking into account any revoked certificates that are
 for OpenSSL only (not GnuTLS), a directory, that contains a collection of
 expected server certificates. The client verifies the server's certificate
 against this collection, taking into account any revoked certificates that are


@@ -24478,6 +24491,14 @@ list of permitted cipher suites. If either of these checks fails, delivery to
 the current host is abandoned, and the &(smtp)& transport tries to deliver to
 alternative hosts, if any.
 
 the current host is abandoned, and the &(smtp)& transport tries to deliver to
 alternative hosts, if any.
 

+.new
+ &*Note*&:
+These options must be set in the &(smtp)& transport for Exim to use TLS when it
+is operating as a client. Exim does not assume that a server certificate (set
+by the global options of the same name) should also be used when operating as a
+client.
+.wen
+

 .vindex "&$host$&"
 .vindex "&$host_address$&"
 All the TLS options in the &(smtp)& transport are expanded before use, with
 .vindex "&$host$&"
 .vindex "&$host_address$&"
 All the TLS options in the &(smtp)& transport are expanded before use, with


@@ -24672,7 +24693,7 @@ options in the main part of the configuration. These options are:
 .irow &%acl_smtp_mail%&        "ACL for MAIL"
 .irow &%acl_smtp_mailauth%&    "ACL for the AUTH parameter of MAIL"
 .irow &%acl_smtp_mime%&        "ACL for content-scanning MIME parts"
 .irow &%acl_smtp_mail%&        "ACL for MAIL"
 .irow &%acl_smtp_mailauth%&    "ACL for the AUTH parameter of MAIL"
 .irow &%acl_smtp_mime%&        "ACL for content-scanning MIME parts"

-.irow &new(&%acl_smtp_notquit%&)  "ACL for non-QUIT terminations"
+.irow &%acl_smtp_notquit%&     "ACL for non-QUIT terminations"

 .irow &%acl_smtp_predata%&     "ACL at start of DATA command"
 .irow &%acl_smtp_quit%&        "ACL for QUIT"
 .irow &%acl_smtp_rcpt%&        "ACL for RCPT"
 .irow &%acl_smtp_predata%&     "ACL at start of DATA command"
 .irow &%acl_smtp_quit%&        "ACL for QUIT"
 .irow &%acl_smtp_rcpt%&        "ACL for RCPT"


@@ -24812,13 +24833,15 @@ client are given temporary error responses until QUIT is received or the
 connection is closed. In these special cases, the QUIT ACL does not run.
 
 
 connection is closed. In these special cases, the QUIT ACL does not run.
 
 

-
+.new

 .section "The not-QUIT ACL" "SECTNOTQUITACL"
 .section "The not-QUIT ACL" "SECTNOTQUITACL"

-The not-QUIT ACL, specified by &%smtp_notquit_acl%&, is run in most cases when
+.vindex &$acl_smtp_notquit$&
+The not-QUIT ACL, specified by &%acl_smtp_notquit%&, 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.
 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.

+.wen

 
 Like the QUIT ACL, this ACL is provided to make it possible to do customized
 logging or to gather statistics, and its outcome is ignored. The &%delay%&
 
 Like the QUIT ACL, this ACL is provided to make it possible to do customized
 logging or to gather statistics, and its outcome is ignored. The &%delay%&


@@ -25126,7 +25149,7 @@ the sending entity receives a &"success"& response. However, &%discard%& causes
 recipients to be discarded. If it is used in an ACL for RCPT, just the one
 recipient is discarded; if used for MAIL, DATA or in the non-SMTP ACL, all the
 message's recipients are discarded. Recipients that are discarded before DATA
 recipients to be discarded. If it is used in an ACL for RCPT, just the one
 recipient is discarded; if used for MAIL, DATA or in the non-SMTP ACL, all the
 message's recipients are discarded. Recipients that are discarded before DATA

-do not appear in the log line when the &%log_recipients%& log selector is set.
+do not appear in the log line when the &%received_recipients%& log selector is set.

 
 If the &%log_message%& modifier is set when &%discard%& operates,
 its contents are added to the line that is automatically written to the log.
 
 If the &%log_message%& modifier is set when &%discard%& operates,
 its contents are added to the line that is automatically written to the log.


@@ -25516,7 +25539,8 @@ ACL fragment writes no logging information when access is denied:
 &`     log_reject_target =`&
 .endd
 This modifier can be used in SMTP and non-SMTP ACLs. It applies to both
 &`     log_reject_target =`&
 .endd
 This modifier can be used in SMTP and non-SMTP ACLs. It applies to both

-permanent and temporary rejections.
+permanent and temporary rejections. Its effect lasts for the rest of the
+current ACL.

 
 
 .vitem &*logwrite*&&~=&~<&'text'&>
 
 
 .vitem &*logwrite*&&~=&~<&'text'&>


@@ -25811,7 +25835,7 @@ This control is permitted only for the MAIL, RCPT, and start of data ACLs (the
 latter is the one defined by &%acl_smtp_predata%&). Setting it tells Exim that
 the current message is a submission from a local MUA. In this case, Exim
 operates in &"submission mode"&, and applies certain fixups to the message if
 latter is the one defined by &%acl_smtp_predata%&). Setting it tells Exim that
 the current message is a submission from a local MUA. In this case, Exim
 operates in &"submission mode"&, and applies certain fixups to the message if

-necessary. For example, it add a &'Date:'& header line if one is not present.
+necessary. For example, it adds a &'Date:'& header line if one is not present.

 This control is not permitted in the &%acl_smtp_data%& ACL, because that is too
 late (the message has already been created).
 
 This control is not permitted in the &%acl_smtp_data%& ACL, because that is too
 late (the message has already been created).
 


@@ -25824,7 +25848,7 @@ that may be received in the same SMTP connection.
 .vitem &*control&~=&~suppress_local_fixups*&
 .cindex "submission fixups, suppressing"
 This control applies to locally submitted (non TCP/IP) messages, and is the
 .vitem &*control&~=&~suppress_local_fixups*&
 .cindex "submission fixups, suppressing"
 This control applies to locally submitted (non TCP/IP) messages, and is the

-complement of &`control`& &`=`& &`submission`&. It disables the fixups that are
+complement of &`control = submission`&. It disables the fixups that are

 normally applied to locally-submitted messages. Specifically:
 
 .ilist
 normally applied to locally-submitted messages. Specifically:
 
 .ilist


@@ -25853,12 +25877,12 @@ All four possibilities for message fixups can be specified:
 .ilist
 Locally submitted, fixups applied: the default.
 .next
 .ilist
 Locally submitted, fixups applied: the default.
 .next

-Locally submitted, no fixups applied: use &`control`& &`=`&
-&`suppress_local_fixups`&.
+Locally submitted, no fixups applied: use
+&`control = suppress_local_fixups`&.

 .next
 Remotely submitted, no fixups applied: the default.
 .next
 .next
 Remotely submitted, no fixups applied: the default.
 .next

-Remotely submitted, fixups applied: use &`control`& &`=`& &`submission`&.
+Remotely submitted, fixups applied: use &`control = submission`&.

 .endlist
 
 
 .endlist
 
 


@@ -26362,7 +26386,9 @@ verified as a sender.
 .cindex "&ACL;" "testing a DNS list"
 In its simplest form, the &%dnslists%& condition tests whether the calling host
 is on at least one of a number of DNS lists by looking up the inverted IP
 .cindex "&ACL;" "testing a DNS list"
 In its simplest form, the &%dnslists%& condition tests whether the calling host
 is on at least one of a number of DNS lists by looking up the inverted IP

-address in one or more DNS domains. For example, if the calling host's IP
+address in one or more DNS domains. (Note that DNS list domains are not mail
+domains, so the &`+`& syntax for named lists doesn't work - it is used for
+special options instead.) For example, if the calling host's IP

 address is 192.168.62.43, and the ACL statement is
 .code
 deny dnslists = blackholes.mail-abuse.org : \
 address is 192.168.62.43, and the ACL statement is
 .code
 deny dnslists = blackholes.mail-abuse.org : \


@@ -26904,7 +26930,6 @@ which may be inaccurate or completely missing. You can follow the limit &'m'&
 in the configuration with K, M, or G to specify limits in kilobytes,
 megabytes, or gigabytes, respectively.
 
 in the configuration with K, M, or G to specify limits in kilobytes,
 megabytes, or gigabytes, respectively.
 

-.new

 The &%per_rcpt%& option causes Exim to limit the rate at which
 recipients are accepted. To be effective, it would need to be used in
 either the &%acl_smtp_rcpt%& or the &%acl_not_smtp%& ACL. In the
 The &%per_rcpt%& option causes Exim to limit the rate at which
 recipients are accepted. To be effective, it would need to be used in
 either the &%acl_smtp_rcpt%& or the &%acl_not_smtp%& ACL. In the


@@ -26920,7 +26945,6 @@ condition is processed. This can be used to limit the SMTP command rate.
 This command is essentially an alias of &%per_rcpt%& to make it clear
 that the effect is to limit the rate at which individual commands,
 rather than recipients, are accepted.
 This command is essentially an alias of &%per_rcpt%& to make it clear
 that the effect is to limit the rate at which individual commands,
 rather than recipients, are accepted.

-.wen

 
 .section "Ratelimit options for handling fast clients" "ratophanfas"
 If a client's average rate is greater than the maximum, the rate limiting
 
 .section "Ratelimit options for handling fast clients" "ratophanfas"
 If a client's average rate is greater than the maximum, the rate limiting


@@ -26941,7 +26965,7 @@ value. You can work out the time (the number of smoothing periods) that a
 client is subjected to counter-measures after an over-limit burst with this
 formula:
 .code
 client is subjected to counter-measures after an over-limit burst with this
 formula:
 .code

-ln(peakrate/maxrate)
+        ln(peakrate/maxrate)

 .endd
 The &%leaky%& (default) option means that the client's recorded rate is not
 updated if it is above the limit. The effect of this is that Exim measures the
 .endd
 The &%leaky%& (default) option means that the client's recorded rate is not
 updated if it is above the limit. The effect of this is that Exim measures the


@@ -27004,7 +27028,7 @@ entry must set the rate for the same key (otherwise it will always be zero).
 For example:
 .code
 acl_check_connect:
 For example:
 .code
 acl_check_connect:

-  deny ratelimit = 100 / 5m / strict / noupdate
+  deny ratelimit = 100 / 5m / strict / per_cmd / noupdate

        log_message = RATE: $sender_rate/$sender_rate_period \
                      (max $sender_rate_limit)
 .endd
        log_message = RATE: $sender_rate/$sender_rate_period \
                      (max $sender_rate_limit)
 .endd


@@ -27599,21 +27623,12 @@ the third string (in this case &"1"&), whether or not the cryptographic and
 timeout checks succeed. The &$prvscheck_result$& variable contains the result
 of the checks (empty for failure, &"1"& for success).
 
 timeout checks succeed. The &$prvscheck_result$& variable contains the result
 of the checks (empty for failure, &"1"& for success).
 

-There are two more issues you must consider when implementing prvs-signing.
-Firstly, you need to ensure that prvs-signed addresses are not blocked by your
-ACLs. A prvs-signed address contains a slash character, but the default Exim
-configuration contains this statement in the RCPT ACL:
-.code
-deny    message       = Restricted characters in address
-        domains       = +local_domains
-        local_parts   = ^[.] : ^.*[@%!/|]
-.endd
-This is a conservative rule that blocks local parts that contain slashes. You
-should remove the slash in the last line.
-
-Secondly, you have to ensure that the routers accept prvs-signed addresses and
+.new
+There is one more issue you must consider when implementing prvs-signing:
+you have to ensure that the routers accept prvs-signed addresses and

 deliver them correctly. The easiest way to handle this is to use a &(redirect)&
 router to remove the signature with a configuration along these lines:
 deliver them correctly. The easiest way to handle this is to use a &(redirect)&
 router to remove the signature with a configuration along these lines:

+.wen

 .code
 batv_redirect:
   driver = redirect
 .code
 batv_redirect:
   driver = redirect


@@ -28177,7 +28192,7 @@ cases.
 These ACLs are called (possibly many times) just before the &%acl_smtp_data%&
 ACL in the case of an SMTP message, or just before the &%acl_not_smtp%& ACL in
 the case of a non-SMTP message. However, a MIME ACL is called only if the
 These ACLs are called (possibly many times) just before the &%acl_smtp_data%&
 ACL in the case of an SMTP message, or just before the &%acl_not_smtp%& ACL in
 the case of a non-SMTP message. However, a MIME ACL is called only if the

-message contains a &new(&'Content-Type:'&) header line. When a call to a MIME
+message contains a &'Content-Type:'& header line. When a call to a MIME

 ACL does not yield &"accept"&, ACL processing is aborted and the appropriate
 result code is sent to the client. In the case of an SMTP message, the
 &%acl_smtp_data%& ACL is not called when this happens.
 ACL does not yield &"accept"&, ACL processing is aborted and the appropriate
 result code is sent to the client. In the case of an SMTP message, the
 &%acl_smtp_data%& ACL is not called when this happens.


@@ -34323,13 +34338,272 @@ unqualified domain &'foundation'&.
 .ecindex IIDforspo2
 .ecindex IIDforspo3
 
 .ecindex IIDforspo2
 .ecindex IIDforspo3
 

+. ////////////////////////////////////////////////////////////////////////////
+. ////////////////////////////////////////////////////////////////////////////
+
+.new
+.chapter "Support for DKIM (DomainKeys Identified Mail) - RFC4871" "CHID12" &&&
+         "DKIM Support"
+.cindex "DKIM"
+
+Since version 4.70, DKIM support is compiled into Exim by default. It can be
+disabled by setting DISABLE_DKIM=yes in Local/Makefile.
+
+Exim's DKIM implementation allows to
+.olist
+Sign outgoing messages: This function is implemented in the SMTP transport.
+It can co-exist with all other Exim features, including transport filters.
+.next
+Verify signatures in incoming messages: This is implemented by an additional
+ACL (acl_smtp_dkim), which can be called several times per message, with
+different signature context.
+.endlist
+
+In typical Exim style, the verification implementation does not include any
+default "policy". Instead it enables you to build your own policy using
+Exim's standard controls.
+
+Please note that verification of DKIM signatures in incoming mail is turned
+on by default for logging purposes. For each signature in incoming email,
+exim will log a line displaying the most important signature details, and the
+signature status. Here is an example:
+.code
+2009-09-09 10:22:28 1MlIRf-0003LU-U3 DKIM: d=facebookmail.com s=q1-2009b c=relaxed/relaxed a=rsa-sha1 i=@facebookmail.com t=1252484542 [verification succeeded]
+.endd
+You might want to turn off DKIM verification processing entirely for internal
+or relay mail sources. To do that, set the &%dkim_disable_verify%& ACL
+control modifier. This should typically be done in the RCPT ACL, at points
+where you accept mail from relay sources (internal hosts or authenticated
+senders).
+
+
+.section "Signing outgoing messages" "SECID513"
+.cindex "DKIM" "signing"
+
+Signing is implemented by setting private options on the SMTP transport.
+These options take (expandable) strings as arguments.
+
+.option dkim_domain smtp string&!! unset
+MANDATORY
+The domain you want to sign with. The result of this expanded
+option is put into the &%$dkim_domain%& expansion variable.
+
+.option dkim_selector smtp string&!! unset
+MANDATORY
+This sets the key selector string. You can use the &%$dkim_domain%& expansion
+variable to look up a matching selector. The result is put in the expansion
+variable &%$dkim_selector%& which should be used in the &%dkim_private_key%&
+option along with &%$dkim_domain%&.
+
+.option dkim_private_key smtp string&!! unset
+MANDATORY
+This sets the private key to use. You can use the &%$dkim_domain%& and
+&%$dkim_selector%& expansion variables to determine the private key to use.
+The result can either
+.ilist
+be a valid RSA private key in ASCII armor, including line breaks.
+.next
+start with a slash, in which case it is treated as a file that contains
+the private key.
+.next
+be "0", "false" or the empty string, in which case the message will not
+be signed. This case will not result in an error, even if &%dkim_strict%&
+is set.
+.endlist
+
+.option dkim_canon smtp string&!! unset
+OPTIONAL
+This option sets the canonicalization method used when signing a message.
+The DKIM RFC currently supports two methods: "simple" and "relaxed".
+The option defaults to "relaxed" when unset. Note: the current implementation
+only supports using the same canonicalization method for both headers and body.
+
+.option dkim_strict smtp string&!! unset
+OPTIONAL
+This  option  defines  how  Exim  behaves  when  signing a message that
+should be signed fails for some reason.  When the expansion evaluates to
+either "1" or "true", Exim will defer. Otherwise Exim will send the message
+unsigned. You can use the &%$dkim_domain%& and &%$dkim_selector%& expansion
+variables here.
+
+.option dkim_sign_headers smtp string&!! unset
+OPTIONAL
+When set, this option must expand to (or be specified as) a colon-separated
+list of header names. Headers with these names will be included in the message
+signature. When unspecified, the header names recommended in RFC4871 will be
+used.
+
+
+.section "Verifying DKIM signatures in incoming mail" "SECID514"
+.cindex "DKIM" "verification"
+
+Verification of DKIM signatures in incoming email is implemented via the
+&%acl_smtp_dkim%& ACL. By default, this ACL is called once for each
+syntactically(!) correct signature in the incoming message.
+
+To evaluate the signature in the ACL a large number of expansion variables
+containing the signature status and its details are set up during the
+runtime of the ACL.
+
+Calling the ACL only for existing signatures is not sufficient to build
+more advanced policies. For that reason, the global option
+&%dkim_verify_signers%&, and a global expansion variable
+&%$dkim_signers%& exist.

 
 

+The global option &%dkim_verify_signers%& can be set to a colon-separated
+list of DKIM domains or identities for which the ACL &%acl_smtp_dkim%& is
+called. It is expanded when the message has been received. At this point,
+the expansion variable &%$dkim_signers%& already contains a colon-
+separated list of signer domains and identities for the message. When
+&%dkim_verify_signers%& is not specified in the main configuration,
+it defaults as:
+.code
+dkim_verify_signers = $dkim_signers
+.endd
+This leads to the default behaviour of calling &%acl_smtp_dkim%& for each
+DKIM signature in the message. Current DKIM verifiers may want to explicitly
+call the ACL for known domains or identities. This would be achieved as follows:
+.code
+dkim_verify_signers = paypal.com:ebay.com:$dkim_signers
+.endd
+This would result in &%acl_smtp_dkim%& always being called for "paypal.com"
+and "ebay.com", plus all domains and identities that have signatures in the message.
+You can also be more creative in constructing your policy. Example:
+.code
+dkim_verify_signers = $sender_address_domain:$dkim_signers
+.endd
+
+If a domain or identity is listed several times in the (expanded) value of
+&%dkim_verify_signers%&, the ACL is only called once for that domain or identity.
+
+
+Inside the &%acl_smtp_dkim%&, the following expansion variables are
+available (from most to least important):
+
+.vlist
+.vitem &%$dkim_cur_signer%&
+The signer that is being evaluated in this ACL run. This can be domain or
+an identity. This is one of the list items from the expanded main option
+&%dkim_verify_signers%& (see above).
+.vitem &%$dkim_verify_status%&
+A string describing the general status of the signature. One of
+.ilist
+&%none%&: There is no signature in the message for the current domain or
+identity (as reflected by &%$dkim_cur_signer%&).
+.next
+&%invalid%&: The signature could not be verified due to a processing error.
+More detail is available in &%$dkim_verify_reason%&.
+.next
+&%fail%&: Verification of the signature failed.  More detail is
+available in &%$dkim_verify_reason%&.
+.next
+&%pass%&: The signature passed verification. It is valid.
+.endlist
+.vitem &%$dkim_verify_reason%&
+A string giving a litte bit more detail when &%$dkim_verify_status%& is either
+"fail" or "invalid". One of
+.ilist
+&%pubkey_unavailable%& (when &%$dkim_verify_status%&="invalid"): The public
+key for the domain could not be retrieved. This may be a temporary problem.
+.next
+&%pubkey_syntax%& (when &%$dkim_verify_status%&="invalid"): The public key
+record for the domain is syntactically invalid.
+.next
+&%bodyhash_mismatch%& (when &%$dkim_verify_status%&="fail"): The calculated
+body hash does not match the one specified in the signature header. This
+means that the message body was modified in transit.
+.next
+&%signature_incorrect%& (when &%$dkim_verify_status%&="fail"): The signature
+could not be verified. This may mean that headers were modified,
+re-written or otherwise changed in a way which is incompatible with
+DKIM verification. It may of course also mean that the signature is forged.
+.endlist
+.vitem &%$dkim_domain%&
+The signing domain. IMPORTANT: This variable is only populated if there is
+an actual signature in the message for the current domain or identity (as
+reflected by &%$dkim_cur_signer%&).
+.vitem &%$dkim_identity%&
+The signing identity, if present. IMPORTANT: This variable is only populated
+if there is an actual signature in the message for the current domain or
+identity (as reflected by &%$dkim_cur_signer%&).
+.vitem &%$dkim_selector%&
+The key record selector string
+.vitem &%$dkim_algo%&
+The algorithm used. One of 'rsa-sha1' or 'rsa-sha256'.
+.vitem &%$dkim_canon_body%&
+The body canonicalization method. One of 'relaxed' or 'simple'.
+.vitem &%dkim_canon_headers%&
+The header canonicalization method. One of 'relaxed' or 'simple'.
+.vitem &%$dkim_copiedheaders%&
+A transcript of headers and their values which are included in the signature
+(copied from the 'z=' tag of the signature).
+.vitem &%$dkim_bodylength%&
+The number of signed body bytes. If zero ("0"), the body is unsigned. If no
+limit was set by the signer, "9999999999999" is returned. This makes sure
+that this variable always expands to an integer value.
+.vitem &%$dkim_created%&
+UNIX timestamp reflecting the date and time when the signature was created.
+When this was not specified by the signer, "0" is returned.
+.vitem &%$dkim_expires%&
+UNIX timestamp reflecting the date and time when the signer wants the
+signature to be treated as "expired". When this was not specified by the
+signer, "9999999999999" is returned. This makes it possible to do useful
+integer size comparisons against this value.
+.vitem &%$dkim_headernames%&
+A colon-separated list of names of headers included in the signature.
+.vitem &%$dkim_key_testing%&
+"1" if the key record has the "testing" flag set, "0" if not.
+.vitem &%$dkim_key_nosubdomaining%&
+"1" if the key record forbids subdomaining, "0" otherwise.
+.vitem &%$dkim_key_srvtype%&
+Service type (tag s=) from the key record. Defaults to "*" if not specified
+in the key record.
+.vitem &%$dkim_key_granularity%&
+Key granularity (tag g=) from the key record. Defaults to "*" if not specified
+in the key record.
+.vitem &%$dkim_key_notes%&
+Notes from the key record (tag n=)
+.endlist

 
 

+In addition, two ACL conditions are provided:
+
+.vlist
+.vitem &%dkim_signers%&
+ACL condition that checks a colon-separated list of domains or identities
+for a match against the domain or identity that the ACL is currently verifying
+(reflected by &%$dkim_cur_signer%&). This is typically used to restrict an ACL
+verb to a group of domains or identities, like:
+
+.code
+# Warn when message apparently from GMail has no signature at all
+warn log_message = GMail sender without DKIM signature
+     sender_domains = gmail.com
+     dkim_signers = gmail.com
+     dkim_status = none
+.endd
+
+.vitem &%dkim_status%&
+ACL condition that checks a colon-separated list of possible DKIM verification
+results agains the actual result of verification. This is typically used
+to restrict an ACL verb to a list of verification outcomes, like:
+
+.code
+deny message = Message from Paypal with invalid or missing signature
+     sender_domains = paypal.com:paypal.de
+     dkim_signers = paypal.com:paypal.de
+     dkim_status = none:invalid:fail
+.endd
+
+The possible status keywords are: 'none','invalid','fail' and 'pass'. Please
+see the documentation of the &%$dkim_verify_status%& expansion variable above
+for more information of what they mean.
+.endlist
+.wen

 
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 
 
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 

-.chapter "Adding new drivers or lookup types" "CHID12" &&&
+.chapter "Adding new drivers or lookup types" "CHID13" &&&

          "Adding drivers or lookups"
 .cindex "adding drivers"
 .cindex "new drivers, adding"
          "Adding drivers or lookups"
 .cindex "adding drivers"
 .cindex "new drivers, adding"