PROXY: fix v2 protocol decode. Bugs 2003, 1747

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index e30f17cc0939540131e3b81dbf1fde921ef3f718..4b1e5af3e3c49e61c95010c108df86875b800bb5 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -45,7 +45,7 @@
 . Update the Copyright year (only) when changing content.
 . /////////////////////////////////////////////////////////////////////////////
 
 . Update the Copyright year (only) when changing content.
 . /////////////////////////////////////////////////////////////////////////////
 

-.set previousversion "4.87"
+.set previousversion "4.88"

 .include ./local_params
 
 .set ACL "access control lists (ACLs)"
 .include ./local_params
 
 .set ACL "access control lists (ACLs)"


@@ -371,13 +371,11 @@ contributors.
 .section "Exim documentation" "SECID1"
 . Keep this example change bar when updating the documentation!
 
 .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.
 Substantive changes from the &previousversion; edition are marked in some
 renditions of the document; this paragraph is so marked if the rendition is
 capable of showing a change indicator.
 .cindex "documentation"
 This edition of the Exim specification applies to version &version() of Exim.
 Substantive changes from the &previousversion; edition are marked in some
 renditions of the document; this paragraph is so marked if the rendition is
 capable of showing a change indicator.

-.wen

 
 This document is very much a reference manual; it is not a tutorial. The reader
 is expected to have some familiarity with the SMTP mail transfer protocol and
 
 This document is very much a reference manual; it is not a tutorial. The reader
 is expected to have some familiarity with the SMTP mail transfer protocol and


@@ -436,6 +434,7 @@ directory are:
 .row &_filter.txt_&          "specification of the filter language"
 .row &_Exim3.upgrade_&       "upgrade notes from release 2 to release 3"
 .row &_Exim4.upgrade_&       "upgrade notes from release 3 to release 4"
 .row &_filter.txt_&          "specification of the filter language"
 .row &_Exim3.upgrade_&       "upgrade notes from release 2 to release 3"
 .row &_Exim4.upgrade_&       "upgrade notes from release 3 to release 4"

+.row &_openssl.txt_&         "installing a current OpenSSL release"

 .endtable
 
 The main specification and the specification of the filtering language are also
 .endtable
 
 The main specification and the specification of the filtering language are also


@@ -2627,6 +2626,8 @@ users to set envelope senders.
 
 .cindex "&'From:'& header line"
 .cindex "&'Sender:'& header line"
 
 .cindex "&'From:'& header line"
 .cindex "&'Sender:'& header line"

+.cindex "header lines" "From:"
+.cindex "header lines" "Sender:"

 For a trusted user, there is never any check on the contents of the &'From:'&
 header line, and a &'Sender:'& line is never added. Furthermore, any existing
 &'Sender:'& line in incoming local (non-TCP/IP) messages is not removed.
 For a trusted user, there is never any check on the contents of the &'From:'&
 header line, and a &'Sender:'& line is never added. Furthermore, any existing
 &'Sender:'& line in incoming local (non-TCP/IP) messages is not removed.


@@ -3049,7 +3050,8 @@ trusted user for the sender of a message to be set in this way.
 .oindex "&%-bmalware%&"
 .cindex "testing", "malware"
 .cindex "malware scan test"
 .oindex "&%-bmalware%&"
 .cindex "testing", "malware"
 .cindex "malware scan test"

-This debugging option causes Exim to scan the given file,
+This debugging option causes Exim to scan the given file or directory
+(depending on the used scanner interface),

 using the malware scanning framework.  The option of &%av_scanner%& influences
 this option, so if &%av_scanner%&'s value is dependent upon an expansion then
 the expansion should have defaults which apply to this invocation.  ACLs are
 using the malware scanning framework.  The option of &%av_scanner%& influences
 this option, so if &%av_scanner%&'s value is dependent upon an expansion then
 the expansion should have defaults which apply to this invocation.  ACLs are


@@ -3824,6 +3826,12 @@ This option is not intended for use by external callers. It is used internally
 by Exim in conjunction with the &%-MC%& option. It signifies that the
 remote host supports the ESMTP &_DSN_& extension.
 
 by Exim in conjunction with the &%-MC%& option. It signifies that the
 remote host supports the ESMTP &_DSN_& extension.
 

+.vitem &%-MCG%&
+.oindex "&%-MCG%&"
+This option is not intended for use by external callers. It is used internally
+by Exim in conjunction with the &%-MC%& option. It signifies that an
+alternate queue is used, named by the following option.
+

 .vitem &%-MCP%&
 .oindex "&%-MCP%&"
 This option is not intended for use by external callers. It is used internally
 .vitem &%-MCP%&
 .oindex "&%-MCP%&"
 This option is not intended for use by external callers. It is used internally


@@ -4370,7 +4378,8 @@ relax this restriction (and also the same requirement for the &%-M%&, &%-R%&,
 and &%-S%& options).
 
 .cindex "queue runner" "description of operation"
 and &%-S%& options).
 
 .cindex "queue runner" "description of operation"

-The &%-q%& option starts one queue runner process. This scans the queue of
+If other commandline options do not specify an action,
+the &%-q%& option starts one queue runner process. This scans the queue of

 waiting messages, and runs a delivery process for each one in turn. It waits
 for each delivery process to finish before starting the next one. A delivery
 process may not actually do any deliveries if the retry times for the addresses
 waiting messages, and runs a delivery process for each one in turn. It waits
 for each delivery process to finish before starting the next one. A delivery
 process may not actually do any deliveries if the retry times for the addresses


@@ -4455,8 +4464,27 @@ The &'l'& (the letter &"ell"&) flag specifies that only local deliveries are to
 be done. If a message requires any remote deliveries, it remains on the queue
 for later delivery.
 
 be done. If a message requires any remote deliveries, it remains on the queue
 for later delivery.
 

-.vitem &%-q%&<&'qflags'&>&~<&'start&~id'&>&~<&'end&~id'&>
+.vitem &%-q[q][i][f[f]][l][G<name>[/<time>]]]%&
+.oindex "&%-qG%&"
+.cindex queue named
+.cindex "named queues"

 .cindex "queue" "delivering specific messages"
 .cindex "queue" "delivering specific messages"

+If the &'G'& flag and a name is present, the queue runner operates on the
+queue with the given name rather than the default queue.
+The name should not contain a &'/'& character.
+For a periodic queue run (see below)
+append to the name a slash and a time value.
+
+If other commandline options specify an action, a &'-qG<name>'& option
+will specify a queue to operate on.
+For example:
+.code
+exim -bp -qGquarantine
+mailq -qGquarantime
+exim -qGoffpeak -Rf @special.domain.example
+.endd
+
+.vitem &%-q%&<&'qflags'&>&~<&'start&~id'&>&~<&'end&~id'&>

 When scanning the queue, Exim can be made to skip over messages whose ids are
 lexically less than a given value by following the &%-q%& option with a
 starting message id. For example:
 When scanning the queue, Exim can be made to skip over messages whose ids are
 lexically less than a given value by following the &%-q%& option with a
 starting message id. For example:


@@ -4891,8 +4919,12 @@ using this syntax:
 .endd
 on a line by itself. Double quotes round the file name are optional. If you use
 the first form, a configuration error occurs if the file does not exist; the
 .endd
 on a line by itself. Double quotes round the file name are optional. If you use
 the first form, a configuration error occurs if the file does not exist; the

-second form does nothing for non-existent files. In all cases, an absolute file
+second form does nothing for non-existent files.
+.new
+The first form allows a relative name. It is resolved relative to
+the directory of the including file. For the second form an absolute file

 name is required.
 name is required.

+.wen

 
 Includes may be nested to any depth, but remember that Exim reads its
 configuration file often, so it is a good idea to keep them to a minimum.
 
 Includes may be nested to any depth, but remember that Exim reads its
 configuration file often, so it is a good idea to keep them to a minimum.


@@ -4998,6 +5030,31 @@ address lists. In Exim 4 these are handled better by named lists &-- see
 section &<<SECTnamedlists>>&.
 
 
 section &<<SECTnamedlists>>&.
 
 

+.section "Builtin macros" "SECTbuiltinmacros"
+Exim defines some macros depending on facilities available, which may
+differ due to build-time definitions and from one release to another.
+All of these macros start with an underscore.
+They can be used to conditionally include parts of a configuration
+(see below).
+
+The following classes of macros are defined:
+.display
+&` _HAVE_*                    `&  build-time defines
+&` _DRIVER_ROUTER_*           `&  router drivers
+&` _DRIVER_TRANSPORT_*        `&  transport drivers
+&` _DRIVER_AUTHENTICATOR_*    `&  authenticator drivers
+&` _OPT_MAIN_*                `&  main config options
+&` _OPT_ROUTERS_*             `&  generic router options
+&` _OPT_TRANSPORTS_*          `&  generic transport options
+&` _OPT_AUTHENTICATORS_*      `&  generic authenticator options
+&` _OPT_ROUTER_*_*            `&  private router options
+&` _OPT_TRANSPORT_*_*         `&  private transport options
+&` _OPT_AUTHENTICATOR_*_*     `&  private authenticator options
+.endd
+
+Use an &"exim -bP macros"& command to get the list of macros.
+
+

 .section "Conditional skips in the configuration file" "SECID46"
 .cindex "configuration file" "conditional skips"
 .cindex "&`.ifdef`&"
 .section "Conditional skips in the configuration file" "SECID46"
 .cindex "configuration file" "conditional skips"
 .cindex "&`.ifdef`&"


@@ -5101,7 +5158,9 @@ with the characters &"0x"&, in which case the remainder is interpreted as a
 hexadecimal number.
 
 If an integer value is followed by the letter K, it is multiplied by 1024; if
 hexadecimal number.
 
 If an integer value is followed by the letter K, it is multiplied by 1024; if

-it is followed by the letter M, it is multiplied by 1024x1024. When the values
+it is followed by the letter M, it is multiplied by 1024x1024;
+if by the letter G, 1024x1024x1024.
+When the values

 of integer option settings are output, values which are an exact multiple of
 1024 or 1024x1024 are sometimes, but not always, printed using the letters K
 and M. The printing style is independent of the actual input format that was
 of integer option settings are output, values which are an exact multiple of
 1024 or 1024x1024 are sometimes, but not always, printed using the letters K
 and M. The printing style is independent of the actual input format that was


@@ -6147,7 +6206,8 @@ errors:
 This causes any temporarily failing address to be retried every 15 minutes for
 2 hours, then at intervals starting at one hour and increasing by a factor of
 1.5 until 16 hours have passed, then every 6 hours up to 4 days. If an address
 This causes any temporarily failing address to be retried every 15 minutes for
 2 hours, then at intervals starting at one hour and increasing by a factor of
 1.5 until 16 hours have passed, then every 6 hours up to 4 days. If an address

-is not delivered after 4 days of temporary failure, it is bounced.
+is not delivered after 4 days of temporary failure, it is bounced. The time is
+measured from first failure, not from the time the message was received.

 
 If the retry section is removed from the configuration, or is empty (that is,
 if no retry rules are defined), Exim will not retry deliveries. This turns
 
 If the retry section is removed from the configuration, or is empty (that is,
 if no retry rules are defined), Exim will not retry deliveries. This turns


@@ -6228,7 +6288,9 @@ Chapter &<<CHAPplaintext>>& covers both.
 Exim supports the use of regular expressions in many of its options. It
 uses the PCRE regular expression library; this provides regular expression
 matching that is compatible with Perl 5. The syntax and semantics of
 Exim supports the use of regular expressions in many of its options. It
 uses the PCRE regular expression library; this provides regular expression
 matching that is compatible with Perl 5. The syntax and semantics of

-regular expressions is discussed in many Perl reference books, and also in
+regular expressions is discussed in
+online Perl manpages, 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/)).
 


@@ -6609,7 +6671,7 @@ lookup types support only literal keys.
 .endlist ilist
 
 
 .endlist ilist
 
 

-.section "Query-style lookup types" "SECID62"
+.section "Query-style lookup types" "SECTquerystylelookups"

 .cindex "lookup" "query-style types"
 .cindex "query-style lookup" "list of types"
 The supported query-style lookup types are listed below. Further details about
 .cindex "lookup" "query-style types"
 .cindex "query-style lookup" "list of types"
 The supported query-style lookup types are listed below. Further details about


@@ -7773,7 +7835,12 @@ domain, host, address and local part lists.
 
 .section "Expansion of lists" "SECTlistexpand"
 .cindex "expansion" "of lists"
 
 .section "Expansion of lists" "SECTlistexpand"
 .cindex "expansion" "of lists"

-Each list is expanded as a single string before it is used. The result of
+Each list is expanded as a single string before it is used.
+
+&'Exception: the router headers_remove option, where list-item
+splitting is done before string-expansion.'&
+
+The result of

 expansion must be a list, possibly containing empty items, which is split up
 into separate items for matching. By default, colon is the separator character,
 but this can be varied if necessary. See sections &<<SECTlistconstruct>>& and
 expansion must be a list, possibly containing empty items, which is split up
 into separate items for matching. By default, colon is the separator character,
 but this can be varied if necessary. See sections &<<SECTlistconstruct>>& and


@@ -9172,8 +9239,8 @@ The environment is adjusted by the &%keep_environment%& and
 .cindex "&%extract%&" "substrings by key"
 The key and <&'string1'&> are first expanded separately. Leading and trailing
 white space is removed from the key (but not from any of the strings). The key
 .cindex "&%extract%&" "substrings by key"
 The key and <&'string1'&> are first expanded separately. Leading and trailing
 white space is removed from the key (but not from any of the strings). The key

-must not consist entirely of digits. The expanded <&'string1'&> must be of the
-form:
+must not be empty and must not consist entirely of digits.
+The expanded <&'string1'&> must be of the form:

 .display
 <&'key1'&> = <&'value1'&>  <&'key2'&> = <&'value2'&> ...
 .endd
 .display
 <&'key1'&> = <&'value1'&>  <&'key2'&> = <&'value2'&> ...
 .endd


@@ -9355,12 +9422,19 @@ message, and any that are added by an ACL statement or by a system
 filter. Header lines that are added to a particular copy of a message by a
 router or transport are not accessible.
 
 filter. Header lines that are added to a particular copy of a message by a
 router or transport are not accessible.
 

-For incoming SMTP messages, no header lines are visible in ACLs that are obeyed
-before the DATA ACL, because the header structure is not set up until the
-message is received. Header lines that are added in a RCPT ACL (for example)
+For incoming SMTP messages, no header lines are visible in
+.new
+ACLs that are obeyed before the data phase completes,
+.wen
+because the header structure is not set up until the message is received.
+They are visible in DKIM, PRDR and DATA ACLs.
+Header lines that are added in a RCPT ACL (for example)

 are saved until the message's incoming header lines are available, at which
 are saved until the message's incoming header lines are available, at which

-point they are added. When a DATA ACL is running, however, header lines added
-by earlier ACLs are visible.
+point they are added.
+.new
+When any of the above ACLs ar
+.wen
+running, however, header lines added by earlier ACLs are visible.

 
 Upper case and lower case letters are synonymous in header names. If the
 following character is white space, the terminating colon may be omitted, but
 
 Upper case and lower case letters are synonymous in header names. If the
 following character is white space, the terminating colon may be omitted, but


@@ -10049,6 +10123,19 @@ Last:user@example.com
 user@example.com
 .endd
 
 user@example.com
 .endd
 

+.vitem &*${base32:*&<&'digits'&>&*}*&
+.cindex "&%base32%& expansion item"
+.cindex "expansion" "conversion to base 32"
+The string must consist entirely of decimal digits. The number is converted to
+base 32 and output as a (empty, for zero) string of characters.
+Only lowercase letters are used.
+
+.vitem &*${base32d:*&<&'base-32&~digits'&>&*}*&
+.cindex "&%base32d%& expansion item"
+.cindex "expansion" "conversion to base 32"
+The string must consist entirely of base-32 digits.
+The number is converted to decimal and output as a string.
+

 .vitem &*${base62:*&<&'digits'&>&*}*&
 .cindex "&%base62%& expansion item"
 .cindex "expansion" "conversion to base 62"
 .vitem &*${base62:*&<&'digits'&>&*}*&
 .cindex "&%base62%& expansion item"
 .cindex "expansion" "conversion to base 62"


@@ -10100,6 +10187,13 @@ escape sequences starting with a backslash. Whether characters with the most
 significant bit set (so-called &"8-bit characters"&) count as printing or not
 is controlled by the &%print_topbitchars%& option.
 
 significant bit set (so-called &"8-bit characters"&) count as printing or not
 is controlled by the &%print_topbitchars%& option.
 

+.vitem &*${escape8bit:*&<&'string'&>&*}*&
+.cindex "expansion" "escaping 8-bit characters"
+.cindex "&%escape8bit%& expansion item"
+If the string contains and characters with the most significant bit set,
+they are converted to escape sequences starting with a backslash.
+Backslashes and DEL characters are also converted.
+

 
 .vitem &*${eval:*&<&'string'&>&*}*&&~and&~&*${eval10:*&<&'string'&>&*}*&
 .cindex "expansion" "expression evaluation"
 
 .vitem &*${eval:*&<&'string'&>&*}*&&~and&~&*${eval10:*&<&'string'&>&*}*&
 .cindex "expansion" "expression evaluation"


@@ -10473,7 +10567,7 @@ variables or headers inside regular expressions.
 .cindex "SHA-1 hash"
 .cindex "expansion" "SHA-1 hashing"
 .cindex certificate fingerprint
 .cindex "SHA-1 hash"
 .cindex "expansion" "SHA-1 hashing"
 .cindex certificate fingerprint

-.cindex "&%sha2%& expansion item"
+.cindex "&%sha1%& expansion item"

 The &%sha1%& operator computes the SHA-1 hash value of the string, and returns
 it as a 40-digit hexadecimal number, in which any letters are in upper case.
 
 The &%sha1%& operator computes the SHA-1 hash value of the string, and returns
 it as a 40-digit hexadecimal number, in which any letters are in upper case.
 


@@ -10481,16 +10575,34 @@ If the string is a single variable of type certificate,
 returns the SHA-1 hash fingerprint of the certificate.
 
 
 returns the SHA-1 hash fingerprint of the certificate.
 
 

-.vitem &*${sha256:*&<&'certificate'&>&*}*&
+.vitem &*${sha256:*&<&'string'&>&*}*&

 .cindex "SHA-256 hash"
 .cindex certificate fingerprint
 .cindex "expansion" "SHA-256 hashing"
 .cindex "&%sha256%& expansion item"
 .cindex "SHA-256 hash"
 .cindex certificate fingerprint
 .cindex "expansion" "SHA-256 hashing"
 .cindex "&%sha256%& expansion item"

-The &%sha256%& operator computes the SHA-256 hash fingerprint of the
-certificate,
+The &%sha256%& operator computes the SHA-256 hash value of the string

 and returns
 it as a 64-digit hexadecimal number, in which any letters are in upper case.
 and returns
 it as a 64-digit hexadecimal number, in which any letters are in upper case.

-Only arguments which are a single variable of certificate type are supported.
+
+If the string is a single variable of type certificate,
+returns the SHA-256 hash fingerprint of the certificate.
+
+
+.vitem &*${sha3:*&<&'string'&>&*}*& &&&
+       &*${sha3_<n>:*&<&'string'&>&*}*&
+.cindex "SHA3 hash"
+.cindex "expansion" "SHA3 hashing"
+.cindex "&%sha3%& expansion item"
+The &%sha3%& operator computes the SHA3-256 hash value of the string
+and returns
+it as a 64-digit hexadecimal number, in which any letters are in upper case.
+
+If a number is appended, separated by an underbar, it specifies
+the output length.  Values of 224, 256, 384 and 512 are accepted;
+with 256 being the default.
+
+The &%sha3%& expansion item is only supported if Exim has been
+compiled with GnuTLS 3.5.0 or later.

 
 
 .vitem &*${stat:*&<&'string'&>&*}*&
 
 
 .vitem &*${stat:*&<&'string'&>&*}*&


@@ -12139,10 +12251,10 @@ a single-component name, Exim calls &[gethostbyname()]& (or
 qualified host name. See also &$smtp_active_hostname$&.
 
 
 qualified host name. See also &$smtp_active_hostname$&.
 
 

-.vitem &$proxy_host_address$& &&&
-       &$proxy_host_port$& &&&
-       &$proxy_target_address$& &&&
-       &$proxy_target_port$& &&&
+.vitem &$proxy_external_address$& &&&
+       &$proxy_external_port$& &&&
+       &$proxy_local_address$& &&&
+       &$proxy_local_port$& &&&

        &$proxy_session$&
 These variables are only available when built with Proxy Protocol
 or Socks5 support
        &$proxy_session$&
 These variables are only available when built with Proxy Protocol
 or Socks5 support


@@ -12177,6 +12289,12 @@ The value set for the &%qualify_domain%& option in the configuration file.
 The value set for the &%qualify_recipient%& option in the configuration file,
 or if not set, the value of &$qualify_domain$&.
 
 The value set for the &%qualify_recipient%& option in the configuration file,
 or if not set, the value of &$qualify_domain$&.
 

+.vitem &$queue_name$&
+.vindex &$queue_name$&
+.cindex "named queues"
+.cindex queues named
+The name of the spool queue in use; empty for the default queue.
+

 .vitem &$rcpt_count$&
 .vindex "&$rcpt_count$&"
 When a message is being received by SMTP, this variable contains the number of
 .vitem &$rcpt_count$&
 .vindex "&$rcpt_count$&"
 When a message is being received by SMTP, this variable contains the number of


@@ -12765,7 +12883,7 @@ When a message is received from a remote host over an encrypted SMTP
 connection, this variable is set to the cipher suite that was negotiated, for
 example DES-CBC3-SHA. In other circumstances, in particular, for message
 received over unencrypted connections, the variable is empty. Testing
 connection, this variable is set to the cipher suite that was negotiated, for
 example DES-CBC3-SHA. In other circumstances, in particular, for message
 received over unencrypted connections, the variable is empty. Testing

-&$tls_cipher$& for emptiness is one way of distinguishing between encrypted and
+&$tls_in_cipher$& for emptiness is one way of distinguishing between encrypted and

 non-encrypted connections during ACL processing.
 
 The deprecated &$tls_cipher$& variable is the same as &$tls_in_cipher$& during message reception,
 non-encrypted connections during ACL processing.
 
 The deprecated &$tls_cipher$& variable is the same as &$tls_in_cipher$& during message reception,


@@ -12900,8 +13018,7 @@ or external command, as described above. It is also used during a
 
 .vitem &$verify_mode$&
 .vindex "&$verify_mode$&"
 
 .vitem &$verify_mode$&
 .vindex "&$verify_mode$&"

-While a router or transport is being run in verify mode
-or for cutthrough delivery,
+While a router or transport is being run in verify mode or for cutthrough delivery,

 contains "S" for sender-verification or "R" for recipient-verification.
 Otherwise, empty.
 
 contains "S" for sender-verification or "R" for recipient-verification.
 Otherwise, empty.
 


@@ -12977,6 +13094,15 @@ overriding the setting of &%perl_at_start%&.
 There is also a command line option &%-pd%& (for delay) which suppresses the
 initial startup, even if &%perl_at_start%& is set.
 
 There is also a command line option &%-pd%& (for delay) which suppresses the
 initial startup, even if &%perl_at_start%& is set.
 

+.ilist
+.oindex "&%perl_taintmode%&"
+.cindex "Perl" "taintmode"
+To provide more security executing Perl code via the embedded Perl
+interpeter, the &%perl_taintmode%& option can be set. This enables the
+taint mode of the Perl interpreter. You are encouraged to set this
+option to a true value. To avoid breaking existing installations, it
+defaults to false.
+

 
 .section "Calling Perl subroutines" "SECID86"
 When the configuration file includes a &%perl_startup%& option you can make use
 
 .section "Calling Perl subroutines" "SECID86"
 When the configuration file includes a &%perl_startup%& option you can make use


@@ -13455,6 +13581,7 @@ listed in more than one group.
 .row &%slow_lookup_log%&             "control logging of slow DNS lookups"
 .row &%syslog_duplication%&          "controls duplicate log lines on syslog"
 .row &%syslog_facility%&             "set syslog &""facility""& field"
 .row &%slow_lookup_log%&             "control logging of slow DNS lookups"
 .row &%syslog_duplication%&          "controls duplicate log lines on syslog"
 .row &%syslog_facility%&             "set syslog &""facility""& field"

+.row &%syslog_pid%&                  "pid in syslog lines"

 .row &%syslog_processname%&          "set syslog &""ident""& field"
 .row &%syslog_timestamp%&            "timestamp syslog lines"
 .row &%write_rejectlog%&             "control use of message log"
 .row &%syslog_processname%&          "set syslog &""ident""& field"
 .row &%syslog_timestamp%&            "timestamp syslog lines"
 .row &%write_rejectlog%&             "control use of message log"


@@ -13505,6 +13632,7 @@ listed in more than one group.
 .table2
 .row &%perl_at_start%&               "always start the interpreter"
 .row &%perl_startup%&                "code to obey when starting Perl"
 .table2
 .row &%perl_at_start%&               "always start the interpreter"
 .row &%perl_startup%&                "code to obey when starting Perl"

+.row &%perl_taintmode%&                     "enable taint mode in Perl"

 .endtable
 
 
 .endtable
 
 


@@ -13716,6 +13844,7 @@ See also the &'Policy controls'& section above.
 .table2
 .row &%accept_8bitmime%&             "advertise 8BITMIME"
 .row &%auth_advertise_hosts%&        "advertise AUTH to these hosts"
 .table2
 .row &%accept_8bitmime%&             "advertise 8BITMIME"
 .row &%auth_advertise_hosts%&        "advertise AUTH to these hosts"

+.row &%chunking_advertise_hosts%&    "advertise CHUNKING to these hosts"

 .row &%dsn_advertise_hosts%&         "advertise DSN extensions to these hosts"
 .row &%ignore_fromline_hosts%&       "allow &""From ""& from these hosts"
 .row &%ignore_fromline_local%&       "allow &""From ""& from local SMTP"
 .row &%dsn_advertise_hosts%&         "advertise DSN extensions to these hosts"
 .row &%ignore_fromline_hosts%&       "allow &""From ""& from these hosts"
 .row &%ignore_fromline_local%&       "allow &""From ""& from local SMTP"


@@ -14205,11 +14334,11 @@ $primary_hostname-$tod_epoch-testing
 See section &<<CALLaddparcall>>& for details of how this value is used.
 
 
 See section &<<CALLaddparcall>>& for details of how this value is used.
 
 

-.option check_log_inodes main integer 0
+.option check_log_inodes main integer 100

 See &%check_spool_space%& below.
 
 
 See &%check_spool_space%& below.
 
 

-.option check_log_space main integer 0
+.option check_log_space main integer 10M

 See &%check_spool_space%& below.
 
 .oindex "&%check_rfc2047_length%&"
 See &%check_spool_space%& below.
 
 .oindex "&%check_rfc2047_length%&"


@@ -14224,11 +14353,11 @@ of the RFC, generates overlong encoded words. If &%check_rfc2047_length%& is
 set false, Exim recognizes encoded words of any length.
 
 
 set false, Exim recognizes encoded words of any length.
 
 

-.option check_spool_inodes main integer 0
+.option check_spool_inodes main integer 100

 See &%check_spool_space%& below.
 
 
 See &%check_spool_space%& below.
 
 

-.option check_spool_space main integer 0
+.option check_spool_space main integer 10M

 .cindex "checking disk space"
 .cindex "disk space, checking"
 .cindex "spool directory" "checking space"
 .cindex "checking disk space"
 .cindex "disk space, checking"
 .cindex "spool directory" "checking space"


@@ -14239,7 +14368,7 @@ message is accepted.
 .vindex "&$log_space$&"
 .vindex "&$spool_inodes$&"
 .vindex "&$spool_space$&"
 .vindex "&$log_space$&"
 .vindex "&$spool_inodes$&"
 .vindex "&$spool_space$&"

-When any of these options are set, they apply to all incoming messages. If you
+When any of these options are nonzero, they apply to all incoming messages. If you

 want to apply different checks to different kinds of message, you can do so by
 testing the variables &$log_inodes$&, &$log_space$&, &$spool_inodes$&, and
 &$spool_space$& in an ACL with appropriate additional conditions.
 want to apply different checks to different kinds of message, you can do so by
 testing the variables &$log_inodes$&, &$log_space$&, &$spool_inodes$&, and
 &$spool_space$& in an ACL with appropriate additional conditions.


@@ -14248,7 +14377,7 @@ testing the variables &$log_inodes$&, &$log_space$&, &$spool_inodes$&, and
 &%check_spool_space%& and &%check_spool_inodes%& check the spool partition if
 either value is greater than zero, for example:
 .code
 &%check_spool_space%& and &%check_spool_inodes%& check the spool partition if
 either value is greater than zero, for example:
 .code

-check_spool_space = 10M
+check_spool_space = 100M

 check_spool_inodes = 100
 .endd
 The spool partition is the one that contains the directory defined by
 check_spool_inodes = 100
 .endd
 The spool partition is the one that contains the directory defined by


@@ -14267,12 +14396,25 @@ SIZE parameter on the MAIL command, its value is added to the
 &%check_spool_space%& is zero, unless &%no_smtp_check_spool_space%& is set.
 
 The values for &%check_spool_space%& and &%check_log_space%& are held as a
 &%check_spool_space%& is zero, unless &%no_smtp_check_spool_space%& is set.
 
 The values for &%check_spool_space%& and &%check_log_space%& are held as a

-number of kilobytes. If a non-multiple of 1024 is specified, it is rounded up.
+number of kilobytes (though specified in bytes).
+If a non-multiple of 1024 is specified, it is rounded up.

 
 For non-SMTP input and for batched SMTP input, the test is done at start-up; on
 failure a message is written to stderr and Exim exits with a non-zero code, as
 it obviously cannot send an error message of any kind.
 
 
 For non-SMTP input and for batched SMTP input, the test is done at start-up; on
 failure a message is written to stderr and Exim exits with a non-zero code, as
 it obviously cannot send an error message of any kind.
 

+There is a slight performance penalty for these checks.
+Versions of Exim preceding 4.88 had these disabled by default;
+high-rate intallations confident they will never run out of resources
+may wish to deliberately disable them.
+
+.option chunking_advertise_hosts main "host list&!!" *
+.cindex CHUNKING advertisement
+.cindex "RFC 3030" "CHUNKING"
+The CHUNKING extension (RFC3030) will be advertised in the EHLO message to
+these hosts.
+Hosts may use the BDAT command as an alternate to DATA.
+

 .option daemon_smtp_ports main string &`smtp`&
 .cindex "port" "for daemon"
 .cindex "TCP/IP" "setting listening ports"
 .option daemon_smtp_ports main string &`smtp`&
 .cindex "port" "for daemon"
 .cindex "TCP/IP" "setting listening ports"


@@ -14294,6 +14436,7 @@ See &%daemon_startup_retries%&.
 .option delay_warning main "time list" 24h
 .cindex "warning of delay"
 .cindex "delay warning, specifying"
 .option delay_warning main "time list" 24h
 .cindex "warning of delay"
 .cindex "delay warning, specifying"

+.cindex "queue" "delay warning"

 When a message is delayed, Exim sends a warning message to the sender at
 intervals specified by this option. The data is a colon-separated list of times
 after which to send warning messages. If the value of the option is an empty
 When a message is delayed, Exim sends a warning message to the sender at
 intervals specified by this option. The data is a colon-separated list of times
 after which to send warning messages. If the value of the option is an empty


@@ -14626,7 +14769,7 @@ not used.
 .option event_action main string&!! unset
 .cindex events
 This option declares a string to be expanded for Exim's events mechanism.
 .option event_action main string&!! unset
 .cindex events
 This option declares a string to be expanded for Exim's events mechanism.

-For details see &<<CHAPevents>>&.
+For details see chapter &<<CHAPevents>>&.

 
 
 .option exim_group main string "compile-time configured"
 
 
 .option exim_group main string "compile-time configured"


@@ -14977,7 +15120,7 @@ If the &%smtp_connection%& log selector is not set, this option has no effect.
 .option hosts_proxy main "host list&!!" unset
 .cindex proxy "proxy protocol"
 This option enables use of Proxy Protocol proxies for incoming
 .option hosts_proxy main "host list&!!" unset
 .cindex proxy "proxy protocol"
 This option enables use of Proxy Protocol proxies for incoming

-connections.  For details see &<<SECTproxyInbound>>&.
+connections.  For details see section &<<SECTproxyInbound>>&.

 
 
 .option hosts_treat_as_local main "domain list&!!" unset
 
 
 .option hosts_treat_as_local main "domain list&!!" unset


@@ -15151,6 +15294,9 @@ connecting on a regular LDAP port.  This is the LDAP equivalent of SMTP's
 of SSL-on-connect.
 In the event of failure to negotiate TLS, the action taken is controlled
 by &%ldap_require_cert%&.
 of SSL-on-connect.
 In the event of failure to negotiate TLS, the action taken is controlled
 by &%ldap_require_cert%&.

+.new
+This option is ignored for &`ldapi`& connections.
+.wen

 
 
 .option ldap_version main integer unset
 
 
 .option ldap_version main integer unset


@@ -15622,14 +15768,20 @@ local parts. Exim's default configuration does this.
 
 
 .option perl_at_start main boolean false
 
 
 .option perl_at_start main boolean false

+.cindex "Perl"

 This option is available only when Exim is built with an embedded Perl
 interpreter. See chapter &<<CHAPperl>>& for details of its use.
 
 
 .option perl_startup main string unset
 This option is available only when Exim is built with an embedded Perl
 interpreter. See chapter &<<CHAPperl>>& for details of its use.
 
 
 .option perl_startup main string unset

+.cindex "Perl"

 This option is available only when Exim is built with an embedded Perl
 interpreter. See chapter &<<CHAPperl>>& for details of its use.
 
 This option is available only when Exim is built with an embedded Perl
 interpreter. See chapter &<<CHAPperl>>& for details of its use.
 

+.option perl_startup main boolean false
+.cindex "Perl"
+This Option enables the taint mode of the embedded Perl interpreter.
+

 
 .option pgsql_servers main "string list" unset
 .cindex "PostgreSQL lookup type" "server list"
 
 .option pgsql_servers main "string list" unset
 .cindex "PostgreSQL lookup type" "server list"


@@ -15869,7 +16021,7 @@ large list. In most situations, &%queue_run_in_order%& should not be set.
 
 
 
 
 
 

-.option queue_run_max main integer 5
+.option queue_run_max main integer&!! 5

 .cindex "queue runner" "maximum number of"
 This controls the maximum number of queue runner processes that an Exim daemon
 can run simultaneously. This does not mean that it starts them all at once,
 .cindex "queue runner" "maximum number of"
 This controls the maximum number of queue runner processes that an Exim daemon
 can run simultaneously. This does not mean that it starts them all at once,


@@ -15884,6 +16036,11 @@ the limit, allowing any number of simultaneous queue runner processes to be
 run. If you do not want queue runs to occur, omit the &%-q%&&'xx'& setting on
 the daemon's command line.
 
 run. If you do not want queue runs to occur, omit the &%-q%&&'xx'& setting on
 the daemon's command line.
 

+.cindex queues named
+.cindex "named queues"
+To set limits for different named queues use
+an expansion depending on the &$queue_name$& variable.
+

 .option queue_smtp_domains main "domain list&!!" unset
 .cindex "queueing incoming messages"
 .cindex "message" "queueing remote deliveries"
 .option queue_smtp_domains main "domain list&!!" unset
 .cindex "queueing incoming messages"
 .cindex "message" "queueing remote deliveries"


@@ -16677,6 +16834,15 @@ If this option is unset, &"mail"& is used. See chapter &<<CHAPlog>>& for
 details of Exim's logging.
 
 
 details of Exim's logging.
 
 

+.option syslog_pid main boolean true
+.cindex "syslog" "pid"
+If &%syslog_pid%& is set false, the PID on Exim's log lines are
+omitted when these lines are sent to syslog. (Syslog normally prefixes
+the log lines with the PID of the logging process automatically.) You need
+to enable the &`+pid`& log selector item, if you want Exim to write it's PID
+into the logs.) See chapter &<<CHAPlog>>& for details of Exim's logging.
+
+

 
 .option syslog_processname main string &`exim`&
 .cindex "syslog" "process name; setting"
 
 .option syslog_processname main string &`exim`&
 .cindex "syslog" "process name; setting"


@@ -16814,8 +16980,8 @@ of the STARTTLS command to set up an encrypted session is advertised in
 response to EHLO only to those client hosts that match this option. See
 chapter &<<CHAPTLS>>& for details of Exim's support for TLS.
 Note that the default value requires that a certificate be supplied
 response to EHLO only to those client hosts that match this option. See
 chapter &<<CHAPTLS>>& for details of Exim's support for TLS.
 Note that the default value requires that a certificate be supplied

-using the &%tls_certificate%& option.  If no certificate is available then
-the &%tls_advertise_hosts%& option should be set empty.
+using the &%tls_certificate%& option.  If TLS support for incoming connections
+is not required the &%tls_advertise_hosts%& option should be set empty.

 
 
 .option tls_certificate main string&!! unset
 
 
 .option tls_certificate main string&!! unset


@@ -16836,6 +17002,9 @@ if the OpenSSL build supports TLS extensions and the TLS client sends the
 Server Name Indication extension, then this option and others documented in
 &<<SECTtlssni>>& will be re-expanded.
 
 Server Name Indication extension, then this option and others documented in
 &<<SECTtlssni>>& will be re-expanded.
 

+If this option is unset or empty a fresh self-signed certificate will be
+generated for every connection.
+

 .option tls_crl main string&!! unset
 .cindex "TLS" "server certificate revocation list"
 .cindex "certificate" "revocation list for server"
 .option tls_crl main string&!! unset
 .cindex "TLS" "server certificate revocation list"
 .cindex "certificate" "revocation list for server"


@@ -16871,7 +17040,13 @@ larger prime than requested.
 The value of this option is expanded and indicates the source of DH parameters
 to be used by Exim.
 
 The value of this option is expanded and indicates the source of DH parameters
 to be used by Exim.
 

-If it is a filename starting with a &`/`&, then it names a file from which DH
+&*Note: The Exim Maintainers strongly recommend using a filename with site-generated
+local DH parameters*&, which has been supported across all versions of Exim.  The
+other specific constants available are a fallback so that even when
+"unconfigured", Exim can offer Perfect Forward Secrecy in older ciphersuites in TLS.
+
+If &%tls_dhparam%& is a filename starting with a &`/`&,
+then it names a file from which DH

 parameters should be loaded.  If the file exists, it should hold a PEM-encoded
 PKCS#3 representation of the DH prime.  If the file does not exist, for
 OpenSSL it is an error.  For GnuTLS, Exim will attempt to create the file and
 parameters should be loaded.  If the file exists, it should hold a PEM-encoded
 PKCS#3 representation of the DH prime.  If the file does not exist, for
 OpenSSL it is an error.  For GnuTLS, Exim will attempt to create the file and


@@ -16888,22 +17063,36 @@ does not exist, Exim will attempt to create it.
 See section &<<SECTgnutlsparam>>& for further details.
 
 If Exim is using OpenSSL and this option is empty or unset, then Exim will load
 See section &<<SECTgnutlsparam>>& for further details.
 
 If Exim is using OpenSSL and this option is empty or unset, then Exim will load

-a default DH prime; the default is the 2048 bit prime described in section
+a default DH prime; the default is Exim-specific but lacks verifiable provenance.
+
+In older versions of Exim the default was the 2048 bit prime described in section

 2.2 of RFC 5114, "2048-bit MODP Group with 224-bit Prime Order Subgroup", which
 in IKE is assigned number 23.
 
 Otherwise, the option must expand to the name used by Exim for any of a number
 2.2 of RFC 5114, "2048-bit MODP Group with 224-bit Prime Order Subgroup", which
 in IKE is assigned number 23.
 
 Otherwise, the option must expand to the name used by Exim for any of a number

-of DH primes specified in RFC 2409, RFC 3526 and RFC 5114.  As names, Exim uses
-"ike" followed by the number used by IKE, of "default" which corresponds to
-"ike23".
+of DH primes specified in RFC 2409, RFC 3526, RFC 5114, RFC 7919, or from other
+sources.  As names, Exim uses a standard specified name, else "ike" followed by
+the number used by IKE, or "default" which corresponds to
+&`exim.dev.20160529.3`&.

 
 

-The available primes are:
+The available standard primes are:
+&`ffdhe2048`&, &`ffdhe3072`&, &`ffdhe4096`&, &`ffdhe6144`&, &`ffdhe8192`&,

 &`ike1`&, &`ike2`&, &`ike5`&,
 &`ike14`&, &`ike15`&, &`ike16`&, &`ike17`&, &`ike18`&,
 &`ike1`&, &`ike2`&, &`ike5`&,
 &`ike14`&, &`ike15`&, &`ike16`&, &`ike17`&, &`ike18`&,

-&`ike22`&, &`ike23`& (aka &`default`&) and &`ike24`&.
+&`ike22`&, &`ike23`& and &`ike24`&.
+
+The available additional primes are:
+&`exim.dev.20160529.1`&, &`exim.dev.20160529.2`& and &`exim.dev.20160529.3`&.

 
 Some of these will be too small to be accepted by clients.
 Some may be too large to be accepted by clients.
 
 Some of these will be too small to be accepted by clients.
 Some may be too large to be accepted by clients.

+The open cryptographic community has suspicions about the integrity of some
+of the later IKE values, which led into RFC7919 providing new fixed constants
+(the "ffdhe" identifiers).
+
+At this point, all of the "ike" values should be considered obsolete;
+they're still in Exim to avoid breaking unusual configurations, but are
+candidates for removal the next time we have backwards-incompatible changes.

 
 The TLS protocol does not negotiate an acceptable size for this; clients tend
 to hard-drop connections if what is offered by the server is unacceptable,
 
 The TLS protocol does not negotiate an acceptable size for this; clients tend
 to hard-drop connections if what is offered by the server is unacceptable,


@@ -16921,17 +17110,19 @@ prior to the 4.80 release, as Debian used to patch Exim to raise the minimum
 acceptable bound from 1024 to 2048.
 
 
 acceptable bound from 1024 to 2048.
 
 

-.option tls_eccurve main string&!! prime256v1
+.option tls_eccurve main string&!! &`auto`&

 .cindex TLS "EC cryptography"
 .cindex TLS "EC cryptography"

-If built with a recent-enough version of OpenSSL,
-this option selects a EC curve for use by Exim.
+This option selects a EC curve for use by Exim.
+
+After expansion it must contain a valid EC curve parameter, such as
+&`prime256v1`&, &`secp384r1`&, or &`P-512`&. Consult your OpenSSL manual
+for valid selections.

 
 

-Curve names of the form &'prime256v1'& are accepted.
-For even more-recent library versions, names of the form &'P-512'&
-are also accepted, plus the special value &'auto'&
-which tells the library to choose.
+For OpenSSL versions before (and not including) 1.0.2, the string
+&`auto`& selects &`prime256v1`&. For more recent OpenSSL versions
+&`auto`& tells the library to choose.

 
 

-If the option is set to an empty string, no EC curves will be enabled.
+If the option expands to an empty string, no EC curves will be enabled.

 
 
 .option tls_ocsp_file main string&!! unset
 
 
 .option tls_ocsp_file main string&!! unset


@@ -17469,7 +17660,7 @@ This applies to all of the SRV, MX, AAAA, A lookup sequence.
 .cindex "DNSSEC" "MX lookup"
 .cindex "security" "MX lookup"
 .cindex "DNS" "DNSSEC"
 .cindex "DNSSEC" "MX lookup"
 .cindex "security" "MX lookup"
 .cindex "DNS" "DNSSEC"

-DNS lookups for domains matching &%dnssec_request_domains%& will be done with
+DNS lookups for domains matching &%dnssec_require_domains%& will be done with

 the dnssec request bit set.  Any returns not having the Authenticated Data bit
 (AD bit) set will be ignored and logged as a host-lookup failure.
 This applies to all of the SRV, MX, AAAA, A lookup sequence.
 the dnssec request bit set.  Any returns not having the Authenticated Data bit
 (AD bit) set will be ignored and logged as a host-lookup failure.
 This applies to all of the SRV, MX, AAAA, A lookup sequence.


@@ -19770,12 +19961,17 @@ list1:   :include:/opt/lists/list1
 .endd
 .next
 .cindex "address redirection" "to black hole"
 .endd
 .next
 .cindex "address redirection" "to black hole"

-Sometimes you want to throw away mail to a particular local part. Making the
-&%data%& option expand to an empty string does not work, because that causes
-the router to decline. Instead, the alias item
+.cindex "delivery" "discard"
+.cindex "delivery" "blackhole"

 .cindex "black hole"
 .cindex "abandoning mail"
 .cindex "black hole"
 .cindex "abandoning mail"

-&':blackhole:'& can be used. It does what its name implies. No delivery is
+Sometimes you want to throw away mail to a particular local part.  Making the
+&%data%& option expand to an empty string does not work, because that causes
+the router to decline. Instead, the alias item
+.code
+:blackhole:
+.endd
+can be used. It does what its name implies. No delivery is

 done, and no error message is generated. This has the same effect as specifying
 &_/dev/null_& as a destination, but it can be independently disabled.
 
 done, and no error message is generated. This has the same effect as specifying
 &_/dev/null_& as a destination, but it can be independently disabled.
 


@@ -20695,7 +20891,7 @@ resent to other recipients.
 .option event_action transports string&!! unset
 .cindex events
 This option declares a string to be expanded for Exim's events mechanism.
 .option event_action transports string&!! unset
 .cindex events
 This option declares a string to be expanded for Exim's events mechanism.

-For details see &<<CHAPevents>>&.
+For details see chapter &<<CHAPevents>>&.

 
 
 .option group transports string&!! "Exim group"
 
 
 .option group transports string&!! "Exim group"


@@ -20745,7 +20941,7 @@ is forced to fail, no action is taken. Other expansion failures are treated as
 errors and cause the delivery to be deferred.
 
 Unlike most options, &%headers_remove%& can be specified multiple times
 errors and cause the delivery to be deferred.
 
 Unlike most options, &%headers_remove%& can be specified multiple times

-for a router; all listed headers are removed.
+for a transport; all listed headers are removed.

 
 &*Warning*&: Because of the separate expansion of the list items,
 items that contain a list separator must have it doubled.
 
 &*Warning*&: Because of the separate expansion of the list items,
 items that contain a list separator must have it doubled.


@@ -23067,12 +23263,12 @@ message_suffix =
 &`\n`& to &`\r\n`& in &%message_suffix%&.
 
 
 &`\n`& to &`\r\n`& in &%message_suffix%&.
 
 

-.option path pipe string "see below"
-This option specifies the string that is set up in the PATH environment
-variable of the subprocess. The default is:
-.code
-/bin:/usr/bin
-.endd
+.option path pipe string&!! "/bin:/usr/bin"
+.new
+This option is expanded and
+.wen
+specifies the string that is set up in the PATH environment
+variable of the subprocess.

 If the &%command%& option does not yield an absolute path name, the command is
 sought in the PATH directories, in the usual way. &*Warning*&: This does not
 apply to a command specified as a transport filter.
 If the &%command%& option does not yield an absolute path name, the command is
 sought in the PATH directories, in the usual way. &*Warning*&: This does not
 apply to a command specified as a transport filter.


@@ -23457,7 +23653,7 @@ of the message. Its value must not be zero. See also &%final_timeout%&.
 .option dkim_canon smtp string&!! unset
 .option dkim_strict smtp string&!! unset
 .option dkim_sign_headers smtp string&!! unset
 .option dkim_canon smtp string&!! unset
 .option dkim_strict smtp string&!! unset
 .option dkim_sign_headers smtp string&!! unset

-DKIM signing options.  For details see &<<SECDKIMSIGN>>&.
+DKIM signing options.  For details see section &<<SECDKIMSIGN>>&.

 
 
 .option delay_after_cutoff smtp boolean true
 
 
 .option delay_after_cutoff smtp boolean true


@@ -23513,7 +23709,7 @@ This applies to all of the SRV, MX, AAAA, A lookup sequence.
 .cindex "DNSSEC" "MX lookup"
 .cindex "security" "MX lookup"
 .cindex "DNS" "DNSSEC"
 .cindex "DNSSEC" "MX lookup"
 .cindex "security" "MX lookup"
 .cindex "DNS" "DNSSEC"

-DNS lookups for domains matching &%dnssec_request_domains%& will be done with
+DNS lookups for domains matching &%dnssec_require_domains%& will be done with

 the dnssec request bit set.  Any returns not having the Authenticated Data bit
 (AD bit) set will be ignored and logged as a host-lookup failure.
 This applies to all of the SRV, MX, AAAA, A lookup sequence.
 the dnssec request bit set.  Any returns not having the Authenticated Data bit
 (AD bit) set will be ignored and logged as a host-lookup failure.
 This applies to all of the SRV, MX, AAAA, A lookup sequence.


@@ -23768,6 +23964,31 @@ connects. If authentication fails, Exim will try to transfer the message
 unauthenticated. See also &%hosts_require_auth%&, and chapter
 &<<CHAPSMTPAUTH>>& for details of authentication.
 
 unauthenticated. See also &%hosts_require_auth%&, and chapter
 &<<CHAPSMTPAUTH>>& for details of authentication.
 

+.option hosts_try_chunking smtp "host list&!!" *
+.cindex CHUNKING "enabling, in client"
+.cindex BDAT "SMTP command"
+.cindex "RFC 3030" "CHUNKING"
+This option provides a list of servers to which, provided they announce
+CHUNKING support, Exim will attempt to use BDAT commands rather than DATA.
+BDAT will not be used in conjuction with a transport filter.
+
+.option hosts_try_fastopen smtp "host list!!" unset
+.cindex "fast open, TCP" "enabling, in client"
+.cindex "TCP Fast Open" "enabling, in client"
+.cindex "RFC 7413" "TCP Fast Open"
+This option provides a list of servers to which, provided
+the facility is supported by this system, Exim will attempt to
+perform a TCP Fast Open.
+No data is sent on the SYN segment but, if the remote server also
+supports the facility, it can send its SMTP banner immediately after
+the SYN,ACK segment.  This can save up to one round-trip time.
+
+The facility is only active for previously-contacted servers,
+as the initiator must present a cookie in the SYN segment.
+
+On (at least some) current Linux distributions the facility must be enabled
+in the kernel by the sysadmin before the support is usable.
+

 .option hosts_try_prdr smtp "host list&!!" *
 .cindex "PRDR" "enabling, optional in client"
 This option provides a list of servers to which, provided they announce
 .option hosts_try_prdr smtp "host list&!!" *
 .cindex "PRDR" "enabling, optional in client"
 This option provides a list of servers to which, provided they announce


@@ -23938,7 +24159,7 @@ the use of the SIZE option altogether.
 .option socks_proxy smtp string&!! unset
 .cindex proxy SOCKS
 This option enables use of SOCKS proxies for connections made by the
 .option socks_proxy smtp string&!! unset
 .cindex proxy SOCKS
 This option enables use of SOCKS proxies for connections made by the

-transport.  For details see &<<SECTproxySOCKS>>&.
+transport.  For details see section &<<SECTproxySOCKS>>&.

 
 
 .option tls_certificate smtp string&!! unset
 
 
 .option tls_certificate smtp string&!! unset


@@ -26552,7 +26773,7 @@ tls:
 .endd
 This accepts a client certificate that is verifiable against any
 of your configured trust-anchors
 .endd
 This accepts a client certificate that is verifiable against any
 of your configured trust-anchors

-which usually means the full set of public CAs)
+(which usually means the full set of public CAs)

 and which has a SAN with a good account name.
 Note that the client cert is on the wire in-clear, including the SAN,
 whereas a plaintext SMTP AUTH done inside TLS is not.
 and which has a SAN with a good account name.
 Note that the client cert is on the wire in-clear, including the SAN,
 whereas a plaintext SMTP AUTH done inside TLS is not.


@@ -26883,7 +27104,8 @@ Documentation of the strings accepted may be found in the GnuTLS manual, under
 &url(http://www.gnutls.org/manual/html_node/Priority-Strings.html),
 but beware that this relates to GnuTLS 3, which may be newer than the version
 installed on your system.  If you are using GnuTLS 3,
 &url(http://www.gnutls.org/manual/html_node/Priority-Strings.html),
 but beware that this relates to GnuTLS 3, which may be newer than the version
 installed on your system.  If you are using GnuTLS 3,

-&url(http://www.gnutls.org/manual/gnutls.html#Listing-the-ciphersuites-in-a-priority-string, then the example code)
+then the example code
+&url(http://www.gnutls.org/manual/gnutls.html#Listing-the-ciphersuites-in-a-priority-string)

 on that site can be used to test a given string.
 
 For example:
 on that site can be used to test a given string.
 
 For example:


@@ -26928,10 +27150,15 @@ with the error
 If a STARTTLS command is issued within an existing TLS session, it is
 rejected with a 554 error code.
 
 If a STARTTLS command is issued within an existing TLS session, it is
 rejected with a 554 error code.
 

-To enable TLS operations on a server, you must set &%tls_advertise_hosts%& to
-match some hosts. You can, of course, set it to * to match all hosts.
-However, this is not all you need to do. TLS sessions to a server won't work
-without some further configuration at the server end.
+To enable TLS operations on a server, the &%tls_advertise_hosts%& option
+must be set to match some hosts. The default is * which matches all hosts.
+
+If this is all you do, TLS encryption will be enabled but not authentication -
+meaning that the peer has no assurance it is actually you he is talking to.
+You gain protection from a passive sniffer listening on the wire but not
+from someone able to intercept the communication.
+
+Further protection requires some further configuration at the server end.

 
 It is rumoured that all existing clients that support TLS/SSL use RSA
 encryption. To make this work you need to set, in the server,
 
 It is rumoured that all existing clients that support TLS/SSL use RSA
 encryption. To make this work you need to set, in the server,


@@ -27306,8 +27533,11 @@ during TLS session handshake, to permit alternative values to be chosen:
 
 Great care should be taken to deal with matters of case, various injection
 attacks in the string (&`../`& or SQL), and ensuring that a valid filename
 
 Great care should be taken to deal with matters of case, various injection
 attacks in the string (&`../`& or SQL), and ensuring that a valid filename

-can always be referenced; it is important to remember that &$tls_sni$& is
+can always be referenced; it is important to remember that &$tls_in_sni$& is

 arbitrary unverified data provided prior to authentication.
 arbitrary unverified data provided prior to authentication.

+Further, the initial cerificate is loaded before SNI is arrived, so
+an expansion for &%tls_certificate%& must have a default which is used
+when &$tls_in_sni$& is empty.

 
 The Exim developers are proceeding cautiously and so far no other TLS options
 are re-expanded.
 
 The Exim developers are proceeding cautiously and so far no other TLS options
 are re-expanded.


@@ -27630,6 +27860,15 @@ received, before the final response to the DATA command is sent. This is
 the ACL specified by &%acl_smtp_data%&, which is the second ACL that is
 associated with the DATA command.
 
 the ACL specified by &%acl_smtp_data%&, which is the second ACL that is
 associated with the DATA command.
 

+.cindex CHUNKING "BDAT command"
+.cindex BDAT "SMTP command"
+.cindex "RFC 3030" CHUNKING
+If CHUNKING was advertised and a BDAT command sequence is received,
+the &%acl_smtp_predata%& ACL is not run.
+. XXX why not?  It should be possible, for the first BDAT.
+The &%acl_smtp_data%& is run after the last BDAT command and all of
+the data specified is received.
+

 For both of these ACLs, it is not possible to reject individual recipients. An
 error response rejects the entire message. Unfortunately, it is known that some
 MTAs do not treat hard (5&'xx'&) responses to the DATA command (either
 For both of these ACLs, it is not possible to reject individual recipients. An
 error response rejects the entire message. Unfortunately, it is known that some
 MTAs do not treat hard (5&'xx'&) responses to the DATA command (either


@@ -27951,7 +28190,7 @@ provides a means of specifying an &"and"& conjunction between conditions. For
 example:
 .code
 deny  dnslists = list1.example
 example:
 .code
 deny  dnslists = list1.example

-dnslists = list2.example
+      dnslists = list2.example

 .endd
 If there are no conditions, the verb is always obeyed. Exim stops evaluating
 the conditions and modifiers when it reaches a condition that fails. What
 .endd
 If there are no conditions, the verb is always obeyed. Exim stops evaluating
 the conditions and modifiers when it reaches a condition that fails. What


@@ -27973,8 +28212,8 @@ after &%endpass%&, the ACL returns &"deny"&. Consider this statement, used to
 check a RCPT command:
 .code
 accept domains = +local_domains
 check a RCPT command:
 .code
 accept domains = +local_domains

-endpass
-verify = recipient
+       endpass
+       verify = recipient

 .endd
 If the recipient domain does not match the &%domains%& condition, control
 passes to the next statement. If it does match, the recipient is verified, and
 .endd
 If the recipient domain does not match the &%domains%& condition, control
 passes to the next statement. If it does match, the recipient is verified, and


@@ -28526,6 +28765,17 @@ all the conditions are true, wherever it appears in an ACL command, whereas
 effect.
 
 
 effect.
 
 

+.vitem &*queue*&&~=&~<&'text'&>
+This modifier specifies the use of a named queue for spool files
+for the message.
+It can only be used before the message is received (i.e. not in
+the DATA ACL).
+This could be used, for example, for known high-volume burst sources
+of traffic, or for quarantine of messages.
+Separate queue-runner processes will be needed for named queues.
+If the text after expansion is empty, the default queue is used.
+
+

 .vitem &*remove_header*&&~=&~<&'text'&>
 This modifier specifies one or more header names in a colon-separated list
  that are to be removed from an incoming message, assuming, of course, that
 .vitem &*remove_header*&&~=&~<&'text'&>
 This modifier specifies one or more header names in a colon-separated list
  that are to be removed from an incoming message, assuming, of course, that


@@ -28612,7 +28862,7 @@ Notice that we put back the lower cased version afterwards, assuming that
 is what is wanted for subsequent tests.
 
 
 is what is wanted for subsequent tests.
 
 

-.vitem &*control&~=&~cutthrough_delivery*&
+.vitem &*control&~=&~cutthrough_delivery/*&<&'options'&>

 .cindex "&ACL;" "cutthrough routing"
 .cindex "cutthrough" "requesting"
 This option requests delivery be attempted while the item is being received.
 .cindex "&ACL;" "cutthrough routing"
 .cindex "cutthrough" "requesting"
 This option requests delivery be attempted while the item is being received.


@@ -28652,11 +28902,18 @@ It is not supported for messages received with the SMTP PRDR option in use.
 
 Should the ultimate destination system positively accept or reject the mail,
 a corresponding indication is given to the source system and nothing is queued.
 
 Should the ultimate destination system positively accept or reject the mail,
 a corresponding indication is given to the source system and nothing is queued.

-If there is a temporary error the item is queued for later delivery in the
-usual fashion. If the item is successfully delivered in cutthrough mode
+If the item is successfully delivered in cutthrough mode

 the delivery log lines are tagged with ">>" rather than "=>" and appear
 before the acceptance "<=" line.
 
 the delivery log lines are tagged with ">>" rather than "=>" and appear
 before the acceptance "<=" line.
 

+If there is a temporary error the item is queued for later delivery in the
+usual fashion.
+This behaviour can be adjusted by appending the option &*defer=*&<&'value'&>
+to the control; the default value is &"spool"& and the alternate value
+&"pass"& copies an SMTP defer response from the target back to the initiator
+and does not queue the message.
+Note that this is independent of any receipient verify conditions in the ACL.
+

 Delivery in this mode avoids the generation of a bounce mail to a
 (possibly faked)
 sender when the destination system is doing content-scan based rejection.
 Delivery in this mode avoids the generation of a bounce mail to a
 (possibly faked)
 sender when the destination system is doing content-scan based rejection.


@@ -28670,13 +28927,16 @@ with &`-d`&, with the output going to a new logfile, by default called
 &'debuglog'&.  The filename can be adjusted with the &'tag'& option, which
 may access any variables already defined.  The logging may be adjusted with
 the &'opts'& option, which takes the same values as the &`-d`& command-line
 &'debuglog'&.  The filename can be adjusted with the &'tag'& option, which
 may access any variables already defined.  The logging may be adjusted with
 the &'opts'& option, which takes the same values as the &`-d`& command-line

-option.  Some examples (which depend on variables that don't exist in all
+option.
+Logging may be stopped, and the file removed, with the &'kill'& option.
+Some examples (which depend on variables that don't exist in all

 contexts):
 .code
       control = debug
       control = debug/tag=.$sender_host_address
       control = debug/opts=+expand+acl
       control = debug/tag=.$message_exim_id/opts=+expand
 contexts):
 .code
       control = debug
       control = debug/tag=.$sender_host_address
       control = debug/opts=+expand+acl
       control = debug/tag=.$message_exim_id/opts=+expand

+      control = debug/kill

 .endd
 
 
 .endd
 
 


@@ -28876,7 +29136,7 @@ that are being submitted at the same time using &%-bs%& or &%-bS%&.
 .vitem &*control&~=&~utf8_downconvert*&
 This control enables conversion of UTF-8 in message addresses
 to a-label form.
 .vitem &*control&~=&~utf8_downconvert*&
 This control enables conversion of UTF-8 in message addresses
 to a-label form.

-For details see &<<SECTi18nMTA>>&.
+For details see section &<<SECTi18nMTA>>&.

 .endlist vlist
 
 
 .endlist vlist
 
 


@@ -28915,7 +29175,7 @@ any ACL verb, including &%deny%& (though this is potentially useful only in a
 RCPT ACL).
 
 Headers will not be added to the message if the modifier is used in
 RCPT ACL).
 
 Headers will not be added to the message if the modifier is used in

-DATA, MIME or DKIM ACLs for messages delivered by cutthrough routing.
+DATA, MIME or DKIM ACLs for a message delivered by cutthrough routing.

 
 Leading and trailing newlines are removed from
 the data for the &%add_header%& modifier; if it then
 
 Leading and trailing newlines are removed from
 the data for the &%add_header%& modifier; if it then


@@ -29016,8 +29276,8 @@ receiving a message). The message must ultimately be accepted for
 with any ACL verb, including &%deny%&, though this is really not useful for
 any verb that doesn't result in a delivered message.
 
 with any ACL verb, including &%deny%&, though this is really not useful for
 any verb that doesn't result in a delivered message.
 

-Headers will not be removed to the message if the modifier is used in
-DATA, MIME or DKIM ACLs for messages delivered by cutthrough routing.
+Headers will not be removed from the message if the modifier is used in
+DATA, MIME or DKIM ACLs for a message delivered by cutthrough routing.

 
 More than one header can be removed at the same time by using a colon separated
 list of header names. The header matching is case insensitive. Wildcards are
 
 More than one header can be removed at the same time by using a colon separated
 list of header names. The header matching is case insensitive. Wildcards are


@@ -31365,6 +31625,15 @@ configuration as follows (example):
 .code
 spamd_address = 192.168.99.45 387
 .endd
 .code
 spamd_address = 192.168.99.45 387
 .endd

+The SpamAssassin protocol relies on a TCP half-close from the client.
+If your SpamAssassin client side is running a Linux system with an
+iptables firewall, consider setting
+&%net.netfilter.nf_conntrack_tcp_timeout_close_wait%& to at least the
+timeout, Exim uses when waiting for a response from the SpamAssassin
+server (currently defaulting to 120s).  With a lower value the Linux
+connection tracking may consider your half-closed connection as dead too
+soon.
+

 
 To use Rspamd (which by default listens on all local addresses
 on TCP port 11333)
 
 To use Rspamd (which by default listens on all local addresses
 on TCP port 11333)


@@ -31395,7 +31664,7 @@ condition defers.
 
 Unix and TCP socket specifications may be mixed in any order.
 Each element of the list is a list itself, space-separated by default
 
 Unix and TCP socket specifications may be mixed in any order.
 Each element of the list is a list itself, space-separated by default

-and changeable in the usual way.
+and changeable in the usual way; take care to not double the separator.

 
 For TCP socket specifications a host name or IP (v4 or v6, but
 subject to list-separator quoting rules) address can be used,
 
 For TCP socket specifications a host name or IP (v4 or v6, but
 subject to list-separator quoting rules) address can be used,


@@ -31522,6 +31791,9 @@ spam bar is 50 characters.
 A multiline text table, containing the full SpamAssassin report for the
 message. Useful for inclusion in headers or reject messages.
 This variable is only usable in a DATA-time ACL.
 A multiline text table, containing the full SpamAssassin report for the
 message. Useful for inclusion in headers or reject messages.
 This variable is only usable in a DATA-time ACL.

+Beware that SpamAssassin may return non-ASCII characters, especially
+when running in country-specific locales, which are not legal
+unencoded in headers.

 
 .vitem &$spam_action$&
 For SpamAssassin either 'reject' or 'no action' depending on the
 
 .vitem &$spam_action$&
 For SpamAssassin either 'reject' or 'no action' depending on the


@@ -33107,6 +33379,7 @@ incoming SMTP message from a source that is not permitted to send them.
 
 .section "Resent- header lines" "SECID220"
 .cindex "&%Resent-%& header lines"
 
 .section "Resent- header lines" "SECID220"
 .cindex "&%Resent-%& header lines"

+.cindex "header lines" "Resent-"

 RFC 2822 makes provision for sets of header lines starting with the string
 &`Resent-`& to be added to a message when it is resent by the original
 recipient to somebody else. These headers are &'Resent-Date:'&,
 RFC 2822 makes provision for sets of header lines starting with the string
 &`Resent-`& to be added to a message when it is resent by the original
 recipient to somebody else. These headers are &'Resent-Date:'&,


@@ -33163,6 +33436,7 @@ existing &'Bcc:'& is not removed.
 
 .section "The Date: header line" "SECID223"
 .cindex "&'Date:'& header line"
 
 .section "The Date: header line" "SECID223"
 .cindex "&'Date:'& header line"

+.cindex "header lines" "Date:"

 If a locally-generated or submission-mode message has no &'Date:'& header line,
 Exim adds one, using the current date and time, unless the
 &%suppress_local_fixups%& control has been specified.
 If a locally-generated or submission-mode message has no &'Date:'& header line,
 Exim adds one, using the current date and time, unless the
 &%suppress_local_fixups%& control has been specified.


@@ -33180,6 +33454,7 @@ messages.
 
 .section "The Envelope-to: header line" "SECID225"
 .cindex "&'Envelope-to:'& header line"
 
 .section "The Envelope-to: header line" "SECID225"
 .cindex "&'Envelope-to:'& header line"

+.cindex "header lines" "Envelope-to:"

 .oindex "&%envelope_to_remove%&"
 &'Envelope-to:'& header lines are not part of the standard RFC 2822 header set.
 Exim can be configured to add them to the final delivery of messages. (See the
 .oindex "&%envelope_to_remove%&"
 &'Envelope-to:'& header lines are not part of the standard RFC 2822 header set.
 Exim can be configured to add them to the final delivery of messages. (See the


@@ -33191,6 +33466,7 @@ messages.
 
 .section "The From: header line" "SECTthefrohea"
 .cindex "&'From:'& header line"
 
 .section "The From: header line" "SECTthefrohea"
 .cindex "&'From:'& header line"

+.cindex "header lines" "From:"

 .cindex "Sendmail compatibility" "&""From""& line"
 .cindex "message" "submission"
 .cindex "submission mode"
 .cindex "Sendmail compatibility" "&""From""& line"
 .cindex "message" "submission"
 .cindex "submission mode"


@@ -33234,6 +33510,7 @@ name as described in section &<<SECTconstr>>&.
 
 .section "The Message-ID: header line" "SECID226"
 .cindex "&'Message-ID:'& header line"
 
 .section "The Message-ID: header line" "SECID226"
 .cindex "&'Message-ID:'& header line"

+.cindex "header lines" "Message-ID:"

 .cindex "message" "submission"
 .oindex "&%message_id_header_text%&"
 If a locally-generated or submission-mode incoming message does not contain a
 .cindex "message" "submission"
 .oindex "&%message_id_header_text%&"
 If a locally-generated or submission-mode incoming message does not contain a


@@ -33249,6 +33526,7 @@ in this header line by setting the &%message_id_header_text%& and/or
 
 .section "The Received: header line" "SECID227"
 .cindex "&'Received:'& header line"
 
 .section "The Received: header line" "SECID227"
 .cindex "&'Received:'& header line"

+.cindex "header lines" "Received:"

 A &'Received:'& header line is added at the start of every message. The
 contents are defined by the &%received_header_text%& configuration option, and
 Exim automatically adds a semicolon and a timestamp to the configured string.
 A &'Received:'& header line is added at the start of every message. The
 contents are defined by the &%received_header_text%& configuration option, and
 Exim automatically adds a semicolon and a timestamp to the configured string.


@@ -33265,6 +33543,7 @@ changed to the time of acceptance, which is (apart from a small delay while the
 
 .section "The References: header line" "SECID228"
 .cindex "&'References:'& header line"
 
 .section "The References: header line" "SECID228"
 .cindex "&'References:'& header line"

+.cindex "header lines" "References:"

 Messages created by the &(autoreply)& transport include a &'References:'&
 header line. This is constructed according to the rules that are described in
 section 3.64 of RFC 2822 (which states that replies should contain such a
 Messages created by the &(autoreply)& transport include a &'References:'&
 header line. This is constructed according to the rules that are described in
 section 3.64 of RFC 2822 (which states that replies should contain such a


@@ -33279,6 +33558,7 @@ incoming message. If there are more than 12, the first one and then the final
 
 .section "The Return-path: header line" "SECID229"
 .cindex "&'Return-path:'& header line"
 
 .section "The Return-path: header line" "SECID229"
 .cindex "&'Return-path:'& header line"

+.cindex "header lines" "Return-path:"

 .oindex "&%return_path_remove%&"
 &'Return-path:'& header lines are defined as something an MTA may insert when
 it does the final delivery of messages. (See the generic &%return_path_add%&
 .oindex "&%return_path_remove%&"
 &'Return-path:'& header lines are defined as something an MTA may insert when
 it does the final delivery of messages. (See the generic &%return_path_add%&


@@ -33291,6 +33571,7 @@ default), Exim removes &'Return-path:'& header lines from incoming messages.
 .section "The Sender: header line" "SECTthesenhea"
 .cindex "&'Sender:'& header line"
 .cindex "message" "submission"
 .section "The Sender: header line" "SECTthesenhea"
 .cindex "&'Sender:'& header line"
 .cindex "message" "submission"

+.cindex "header lines" "Sender:"

 For a locally-originated message from an untrusted user, Exim may remove an
 existing &'Sender:'& header line, and it may add a new one. You can modify
 these actions by setting the &%local_sender_retain%& option true, the
 For a locally-originated message from an untrusted user, Exim may remove an
 existing &'Sender:'& header line, and it may add a new one. You can modify
 these actions by setting the &%local_sender_retain%& option true, the


@@ -35259,6 +35540,7 @@ picked out by the distinctive two-character flags that immediately follow the
 timestamp. The flags are:
 .display
 &`<=`&     message arrival
 timestamp. The flags are:
 .display
 &`<=`&     message arrival

+&`(=`&     message fakereject

 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery
 &`>>`&     cutthrough message delivery
 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery
 &`>>`&     cutthrough message delivery


@@ -35486,14 +35768,18 @@ the following table:
 &`CV  `&        certificate verification status
 &`D   `&        duration of &"no mail in SMTP session"&
 &`DN  `&        distinguished name from peer certificate
 &`CV  `&        certificate verification status
 &`D   `&        duration of &"no mail in SMTP session"&
 &`DN  `&        distinguished name from peer certificate

+&`DS  `&        DNSSEC secured lookups

 &`DT  `&        on &`=>`& lines: time taken for a delivery
 &`F   `&        sender address (on delivery lines)
 &`H   `&        host name and IP address
 &`I   `&        local interface used
 &`DT  `&        on &`=>`& lines: time taken for a delivery
 &`F   `&        sender address (on delivery lines)
 &`H   `&        host name and IP address
 &`I   `&        local interface used

+&`K   `&        CHUNKING extension used

 &`id  `&        message id for incoming message
 &`P   `&        on &`<=`& lines: protocol used
 &`    `&        on &`=>`& and &`**`& lines: return path
 &`id  `&        message id for incoming message
 &`P   `&        on &`<=`& lines: protocol used
 &`    `&        on &`=>`& and &`**`& lines: return path

-&`PRX `&        on &'<='& and&`=>`& lines: proxy address
+&`PRDR`&        PRDR extension used
+&`PRX `&        on &`<=`& and &`=>`& lines: proxy address
+&`Q   `&        alternate queue name

 &`QT  `&        on &`=>`& lines: time spent on queue so far
 &`    `&        on &"Completed"& lines: time spent on queue
 &`R   `&        on &`<=`& lines: reference for local bounce
 &`QT  `&        on &`=>`& lines: time spent on queue so far
 &`    `&        on &"Completed"& lines: time spent on queue
 &`R   `&        on &`<=`& lines: reference for local bounce


@@ -35576,6 +35862,7 @@ selection marked by asterisks:
 &` deliver_time               `&  time taken to perform delivery
 &` delivery_size              `&  add &`S=`&&'nnn'& to => lines
 &`*dnslist_defer              `&  defers of DNS list (aka RBL) lookups
 &` deliver_time               `&  time taken to perform delivery
 &` delivery_size              `&  add &`S=`&&'nnn'& to => lines
 &`*dnslist_defer              `&  defers of DNS list (aka RBL) lookups

+&` dnssec                     `&  DNSSEC secured lookups

 &`*etrn                       `&  ETRN commands
 &`*host_lookup_failed         `&  as it says
 &` ident_timeout              `&  timeout for ident connection
 &`*etrn                       `&  ETRN commands
 &`*host_lookup_failed         `&  as it says
 &` ident_timeout              `&  timeout for ident connection


@@ -35683,6 +35970,14 @@ the &"=>"& line, tagged with S=.
 &%dnslist_defer%&: A log entry is written if an attempt to look up a host in a
 DNS black list suffers a temporary error.
 .next
 &%dnslist_defer%&: A log entry is written if an attempt to look up a host in a
 DNS black list suffers a temporary error.
 .next

+.cindex log dnssec
+.cindex dnssec logging
+&%dnssec%&: For message acceptance and (attempted) delivery log lines, when
+dns lookups gave secure results a tag of DS is added.
+For acceptance this covers the reverse and forward lookups for host name verification.
+It does not cover helo-name verification.
+For delivery this covers the SRV, MX, A and/or AAAA lookups.
+.next

 .cindex "log" "ETRN commands"
 .cindex "ETRN" "logging"
 &%etrn%&: Every valid ETRN command that is received is logged, before the ACL
 .cindex "log" "ETRN commands"
 .cindex "ETRN" "logging"
 &%etrn%&: Every valid ETRN command that is received is logged, before the ACL


@@ -37882,14 +38177,14 @@ DKIM is documented in RFC 4871.
 DKIM support is compiled into Exim by default if TLS support is present.
 It can be disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
 
 DKIM support is compiled into Exim by default if TLS support is present.
 It can be disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
 

-Exim's DKIM implementation allows to
+Exim's DKIM implementation allows for

 .olist
 .olist

-Sign outgoing messages: This function is implemented in the SMTP transport.
+Signing outgoing messages: This function is implemented in the SMTP transport.

 It can co-exist with all other Exim features
 (including transport filters)
 except cutthrough delivery.
 .next
 It can co-exist with all other Exim features
 (including transport filters)
 except cutthrough delivery.
 .next

-Verify signatures in incoming messages: This is implemented by an additional
+Verifying 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 contexts.
 .endlist
 ACL (acl_smtp_dkim), which can be called several times per message, with
 different signature contexts.
 .endlist


@@ -37918,13 +38213,14 @@ senders).
 .section "Signing outgoing messages" "SECDKIMSIGN"
 .cindex "DKIM" "signing"
 
 .section "Signing outgoing messages" "SECDKIMSIGN"
 .cindex "DKIM" "signing"
 

-Signing is implemented by setting private options on the SMTP transport.
+Signing is enabled 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.
 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.

+If it is empty after expansion, DKIM signing is not done.

 
 .option dkim_selector smtp string&!! unset
 MANDATORY:
 
 .option dkim_selector smtp string&!! unset
 MANDATORY:


@@ -37975,7 +38271,7 @@ used.
 .section "Verifying DKIM signatures in incoming mail" "SECID514"
 .cindex "DKIM" "verification"
 
 .section "Verifying DKIM signatures in incoming mail" "SECID514"
 .cindex "DKIM" "verification"
 

-Verification of DKIM signatures in incoming email is implemented via the
+Verification of DKIM signatures in SMTP 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.
 A missing ACL definition defaults to accept.
 &%acl_smtp_dkim%& ACL. By default, this ACL is called once for each
 syntactically(!) correct signature in the incoming message.
 A missing ACL definition defaults to accept.


@@ -38028,6 +38324,7 @@ available (from most to least important):
 The signer that is being evaluated in this ACL run. This can be a domain or
 an identity. This is one of the list items from the expanded main option
 &%dkim_verify_signers%& (see above).
 The signer that is being evaluated in this ACL run. This can be a domain or
 an identity. This is one of the list items from the expanded main option
 &%dkim_verify_signers%& (see above).

+

 .vitem &%$dkim_verify_status%&
 A string describing the general status of the signature. One of
 .ilist
 .vitem &%$dkim_verify_status%&
 A string describing the general status of the signature. One of
 .ilist


@@ -38042,6 +38339,7 @@ available in &%$dkim_verify_reason%&.
 .next
 &%pass%&: The signature passed verification. It is valid.
 .endlist
 .next
 &%pass%&: The signature passed verification. It is valid.
 .endlist

+

 .vitem &%$dkim_verify_reason%&
 A string giving a little bit more detail when &%$dkim_verify_status%& is either
 "fail" or "invalid". One of
 .vitem &%$dkim_verify_reason%&
 A string giving a little bit more detail when &%$dkim_verify_status%& is either
 "fail" or "invalid". One of


@@ -38061,51 +38359,71 @@ 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
 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 &%$dkim_domain%&
 The signing domain. IMPORTANT: This variable is only populated if there is
 an actual signature in the message for the current domain or identity (as
 reflected by &%$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 &%$dkim_identity%&
 The signing identity, if present. IMPORTANT: This variable is only populated
 if there is an actual signature in the message for the current domain or
 identity (as reflected by &%$dkim_cur_signer%&).

+

 .vitem &%$dkim_selector%&
 The key record selector string.
 .vitem &%$dkim_selector%&
 The key record selector string.

+

 .vitem &%$dkim_algo%&
 The algorithm used. One of 'rsa-sha1' or 'rsa-sha256'.
 .vitem &%$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_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_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_copiedheaders%&
 A transcript of headers and their values which are included in the signature
 (copied from the 'z=' tag of the signature).

+Note that RFC6376 requires that verification fail if the From: header is
+not included in the signature.  Exim does not enforce this; sites wishing
+strict enforcement should code the check explicitly.
+

 .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_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_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_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_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_testing%&
 "1" if the key record has the "testing" flag set, "0" if not.

+

 .vitem &%$dkim_key_nosubdomains%&
 "1" if the key record forbids subdomaining, "0" otherwise.
 .vitem &%$dkim_key_nosubdomains%&
 "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_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_granularity%&
 Key granularity (tag g=) from the key record. Defaults to "*" if not specified
 in the key record.

+

 .vitem &%$dkim_key_notes%&
 Notes from the key record (tag n=).
 .vitem &%$dkim_key_notes%&
 Notes from the key record (tag n=).

+

 .vitem &%$dkim_key_length%&
 Number of bits in the key.
 .endlist
 .vitem &%$dkim_key_length%&
 Number of bits in the key.
 .endlist


@@ -38120,13 +38438,16 @@ for a match against the domain or identity that the ACL is currently verifying
 verb to a group of domains or identities. For example:
 
 .code
 verb to a group of domains or identities. For example:
 
 .code

-# Warn when Mail purportedly from GMail has no signature at all
-warn log_message = GMail sender without DKIM signature
+# Warn when Mail purportedly from GMail has no gmail signature
+warn log_message = GMail sender without gmail.com DKIM signature

      sender_domains = gmail.com
      dkim_signers = gmail.com
      dkim_status = none
 .endd
 
      sender_domains = gmail.com
      dkim_signers = gmail.com
      dkim_status = none
 .endd
 

+Note that the above does not check for a total lack of DKIM signing;
+for that check for empty &$h_DKIM-Signature:$& in the data ACL.
+

 .vitem &%dkim_status%&
 ACL condition that checks a colon-separated list of possible DKIM verification
 results against the actual result of verification. This is typically used
 .vitem &%dkim_status%&
 ACL condition that checks a colon-separated list of possible DKIM verification
 results against the actual result of verification. This is typically used


@@ -38168,9 +38489,9 @@ To include this support, include &"SUPPORT_PROXY=yes"&
 in Local/Makefile.
 
 It was built on specifications from:
 in Local/Makefile.
 
 It was built on specifications from:

-http://haproxy.1wt.eu/download/1.5/doc/proxy-protocol.txt
+(&url(http://haproxy.1wt.eu/download/1.5/doc/proxy-protocol.txt)).

 That URL was revised in May 2014 to version 2 spec:
 That URL was revised in May 2014 to version 2 spec:

-http://git.1wt.eu/web?p=haproxy.git;a=commitdiff;h=afb768340c9d7e50d8e
+(&url(http://git.1wt.eu/web?p=haproxy.git;a=commitdiff;h=afb768340c9d7e50d8e)).

 
 The purpose of this facility is so that an application load balancer,
 such as HAProxy, can sit in front of several Exim servers
 
 The purpose of this facility is so that an application load balancer,
 such as HAProxy, can sit in front of several Exim servers


@@ -38189,13 +38510,13 @@ The following expansion variables are usable
 (&"internal"& and &"external"& here refer to the interfaces
 of the proxy):
 .display
 (&"internal"& and &"external"& here refer to the interfaces
 of the proxy):
 .display

-&'proxy_host_address   '& internal IP address of the proxy
-&'proxy_host_port      '& internal TCP port of the proxy
-&'proxy_target_address '& external IP address of the proxy
-&'proxy_target_port    '& external TCP port of the proxy
+&'proxy_external_address   '& IP of host being proxied or IP of remote interface of proxy
+&'proxy_external_port      '& Port of host being proxied or Port on remote interface of proxy
+&'proxy_local_address '& IP of proxy server inbound or IP of local interface of proxy
+&'proxy_local_port    '& Port of proxy server inbound or Port on local interface of proxy

 &'proxy_session        '& boolean: SMTP connection via proxy
 .endd
 &'proxy_session        '& boolean: SMTP connection via proxy
 .endd

-If &$proxy_session$& is set but &$proxy_host_address$& is empty
+If &$proxy_session$& is set but &$proxy_external_address$& is empty

 there was a protocol error.
 
 Since the real connections are all coming from the proxy, and the
 there was a protocol error.
 
 Since the real connections are all coming from the proxy, and the


@@ -38335,7 +38656,7 @@ form of the name.
 Log lines and Received-by: header lines will acquire a "utf8"
 prefix on the protocol element, eg. utf8esmtp.
 
 Log lines and Received-by: header lines will acquire a "utf8"
 prefix on the protocol element, eg. utf8esmtp.
 

-The following expansion operator can be used:
+The following expansion operators can be used:

 .code
 ${utf8_domain_to_alabel:str}
 ${utf8_domain_from_alabel:str}
 .code
 ${utf8_domain_to_alabel:str}
 ${utf8_domain_from_alabel:str}


@@ -38417,7 +38738,7 @@ must be representable in UTF-16.
 .cindex events
 
 The events mechanism in Exim can be used to intercept processing at a number
 .cindex events
 
 The events mechanism in Exim can be used to intercept processing at a number

-of points.  It was originally invented to giave a way to do customised logging
+of points.  It was originally invented to give a way to do customised logging

 actions (for example, to a database) but can also be used to modify some
 processing actions.
 
 actions (for example, to a database) but can also be used to modify some
 processing actions.
 


@@ -38487,7 +38808,7 @@ with the event type:
 The :defer events populate one extra variable: &$event_defer_errno$&.
 
 For complex operations an ACL expansion can be used in &%event_action%&
 The :defer events populate one extra variable: &$event_defer_errno$&.
 
 For complex operations an ACL expansion can be used in &%event_action%&

-however due to the multiple contextx that Exim operates in during
+however due to the multiple contexts that Exim operates in during

 the course of its processing:
 .ilist
 variables set in transport events will not be visible outside that
 the course of its processing:
 .ilist
 variables set in transport events will not be visible outside that