TFO: change the default for hosts_try_fastopen, enabling use by default

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index f0bfd0eb8f431de99e4b7b9557379653ab98bcdb..bfacdef81e69f5e311acdc2249bc12d05c3aba0d 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -2766,6 +2766,8 @@ used to specify a path on the command line if a pid file is required.
 The SIGHUP signal
 .cindex "SIGHUP"
 .cindex "daemon" "restarting"
 The SIGHUP signal
 .cindex "SIGHUP"
 .cindex "daemon" "restarting"

+.cindex signal "to reload configuration"
+.cindex daemon "reload configuration"

 can be used to cause the daemon to re-execute itself. This should be done
 whenever Exim's configuration file, or any file that is incorporated into it by
 means of the &%.include%& facility, is changed, and also whenever a new version
 can be used to cause the daemon to re-execute itself. This should be done
 whenever Exim's configuration file, or any file that is incorporated into it by
 means of the &%.include%& facility, is changed, and also whenever a new version


@@ -9198,6 +9200,7 @@ Many strings in Exim's runtime configuration are expanded before use. Some of
 them are expanded every time they are used; others are expanded only once.
 
 When a string is being expanded it is copied verbatim from left to right except
 them are expanded every time they are used; others are expanded only once.
 
 When a string is being expanded it is copied verbatim from left to right except

+.cindex expansion "string concatenation"

 when a dollar or backslash character is encountered. A dollar specifies the
 start of a portion of the string that is interpreted and replaced as described
 below in section &<<SECTexpansionitems>>& onwards. Backslash is used as an
 when a dollar or backslash character is encountered. A dollar specifies the
 start of a portion of the string that is interpreted and replaced as described
 below in section &<<SECTexpansionitems>>& onwards. Backslash is used as an


@@ -10954,11 +10957,15 @@ 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 &*${sha256:*&<&'string'&>&*}*&
+.vitem &*${sha256:*&<&'string'&>&*}*& &&&
+       &*${sha2:*&<&'string'&>&*}*& &&&
+       &*${sha2_<n>:*&<&'string'&>&*}*&

 .cindex "SHA-256 hash"
 .cindex "SHA-256 hash"

+.cindex "SHA-2 hash"

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

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

 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.
 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.


@@ -10966,6 +10973,15 @@ it as a 64-digit hexadecimal number, in which any letters are in upper case.
 If the string is a single variable of type certificate,
 returns the SHA-256 hash fingerprint of the certificate.
 
 If the string is a single variable of type certificate,
 returns the SHA-256 hash fingerprint of the certificate.
 

+.new
+The operator can also be spelled &%sha2%& and does the same as &%sha256%&
+(except for certificates, which are not supported).
+Finally, if an underbar
+and a number is appended it specifies the output length, selecting a
+member of the SHA-2 family of hash functions.
+Values of 256, 384 and 512 are accepted, with 256 being the default.
+.wen
+

 
 .vitem &*${sha3:*&<&'string'&>&*}*& &&&
        &*${sha3_<n>:*&<&'string'&>&*}*&
 
 .vitem &*${sha3:*&<&'string'&>&*}*& &&&
        &*${sha3_<n>:*&<&'string'&>&*}*&


@@ -12180,6 +12196,7 @@ This variable contains the version string of the Exim build.
 The first character is a major version number, currently 4.
 Then after a dot, the next group of digits is a minor version number.
 There may be other characters following the minor version.
 The first character is a major version number, currently 4.
 Then after a dot, the next group of digits is a minor version number.
 There may be other characters following the minor version.

+This value may be overridden by the &%exim_version%& main config option.

 
 .vitem &$header_$&<&'name'&>
 This is not strictly an expansion variable. It is expansion syntax for
 
 .vitem &$header_$&<&'name'&>
 This is not strictly an expansion variable. It is expansion syntax for


@@ -13511,7 +13528,8 @@ Otherwise, empty.
 
 .vitem &$version_number$&
 .vindex "&$version_number$&"
 
 .vitem &$version_number$&
 .vindex "&$version_number$&"

-The version number of Exim.
+The version number of Exim. Same as &$exim_version$&, may be overridden
+by the &%exim_version%& main config option.

 
 .vitem &$warn_message_delay$&
 .vindex "&$warn_message_delay$&"
 
 .vitem &$warn_message_delay$&
 .vindex "&$warn_message_delay$&"


@@ -15342,6 +15360,14 @@ not also supplied, the gid is taken from the result of &[getpwnam()]& if it is
 used. See chapter &<<CHAPsecurity>>& for a discussion of security issues.
 
 
 used. See chapter &<<CHAPsecurity>>& for a discussion of security issues.
 
 

+.option exim_version main string "current version"
+.cindex "Exim version"
+.cindex customizing "version number"
+.cindex "version number of Exim" override
+This option allows to override the &$version_number$&/&$exim_version$& Exim reports in
+various places.  Use with care, this may fool stupid security scanners.
+
+

 .option extra_local_interfaces main "string list" unset
 This option defines network interfaces that are to be considered local when
 routing, but which are not used for listening by the daemon. See section
 .option extra_local_interfaces main "string list" unset
 This option defines network interfaces that are to be considered local when
 routing, but which are not used for listening by the daemon. See section


@@ -16167,7 +16193,7 @@ harm. This option overrides the &%pipe_as_creator%& option of the &(pipe)&
 transport driver.
 
 
 transport driver.
 
 

-.option openssl_options main "string list" "+no_sslv2 +single_dh_use +no_ticket"
+.option openssl_options main "string list" "+no_sslv2 +no_sslv3 +single_dh_use +no_ticket"

 .cindex "OpenSSL "compatibility options"
 This option allows an administrator to adjust the SSL options applied
 by OpenSSL to connections.  It is given as a space-separated list of items,
 .cindex "OpenSSL "compatibility options"
 This option allows an administrator to adjust the SSL options applied
 by OpenSSL to connections.  It is given as a space-separated list of items,


@@ -17563,7 +17589,7 @@ use when sending messages as a client, you must set the &%tls_certificate%&
 option in the relevant &(smtp)& transport.
 
 &*Note*&: If you use filenames based on IP addresses, change the list
 option in the relevant &(smtp)& transport.
 
 &*Note*&: If you use filenames based on IP addresses, change the list

-separator in the usual way (&<<SECTlistsepchange>>&) >to avoid confusion under IPv6.
+separator in the usual way (&<<SECTlistsepchange>>&) to avoid confusion under IPv6.

 
 &*Note*&: Under versions of OpenSSL preceding 1.1.1,
 when a list of more than one
 
 &*Note*&: Under versions of OpenSSL preceding 1.1.1,
 when a list of more than one


@@ -24566,13 +24592,15 @@ been started will not be passed to a new delivery process for sending another
 message on the same connection. See section &<<SECTmulmessam>>& for an
 explanation of when this might be needed.
 
 message on the same connection. See section &<<SECTmulmessam>>& for an
 explanation of when this might be needed.
 

-.option hosts_noproxy_tls smtp "host list&!!" *
+.new
+.option hosts_noproxy_tls smtp "host list&!!" unset

 .cindex "TLS" "passing connection"
 .cindex "multiple SMTP deliveries"
 .cindex "TLS" "multiple message deliveries"
 For any host that matches this list, a TLS session which has
 been started will not be passed to a new delivery process for sending another
 message on the same session.
 .cindex "TLS" "passing connection"
 .cindex "multiple SMTP deliveries"
 .cindex "TLS" "multiple message deliveries"
 For any host that matches this list, a TLS session which has
 been started will not be passed to a new delivery process for sending another
 message on the same session.

+.wen

 
 The traditional implementation closes down TLS and re-starts it in the new
 process, on the same open TCP connection, for each successive message
 
 The traditional implementation closes down TLS and re-starts it in the new
 process, on the same open TCP connection, for each successive message


@@ -24668,7 +24696,7 @@ 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 conjunction with a transport filter.
 
 CHUNKING support, Exim will attempt to use BDAT commands rather than DATA.
 BDAT will not be used in conjunction with a transport filter.
 

-.option hosts_try_dane smtp "host list&!!" unset
+.option hosts_try_dane smtp "host list&!!" *

 .cindex DANE "transport options"
 .cindex DANE "attempting for certain servers"
 If built with DANE support, Exim  will lookup a
 .cindex DANE "transport options"
 .cindex DANE "attempting for certain servers"
 If built with DANE support, Exim  will lookup a


@@ -24678,7 +24706,7 @@ a DANE-verified TLS connection is made to that host;
 there will be no fallback to in-clear communication.
 See section &<<SECDANE>>&.
 
 there will be no fallback to in-clear communication.
 See section &<<SECDANE>>&.
 

-.option hosts_try_fastopen smtp "host list&!!" unset
+.option hosts_try_fastopen smtp "host list&!!" *

 .cindex "fast open, TCP" "enabling, in client"
 .cindex "TCP Fast Open" "enabling, in client"
 .cindex "RFC 7413" "TCP Fast Open"
 .cindex "fast open, TCP" "enabling, in client"
 .cindex "TCP Fast Open" "enabling, in client"
 .cindex "RFC 7413" "TCP Fast Open"


@@ -28317,7 +28345,7 @@ There is no current way to staple a proof for a client certificate.
 
 
 
 
 
 

-.section "Configuring an Exim client to use TLS" "SECID185"
+.section "Configuring an Exim client to use TLS" "SECTclientTLS"

 .cindex "cipher" "logging"
 .cindex "log" "TLS cipher"
 .cindex "log" "distinguished name"
 .cindex "cipher" "logging"
 .cindex "log" "TLS cipher"
 .cindex "log" "distinguished name"


@@ -30842,7 +30870,7 @@ For SMTP input that does not come over TCP/IP (the &%-bs%& command line
 option), this condition is always true.
 
 
 option), this condition is always true.
 
 

-.vitem &*verify&~=&~not_blind*&
+.vitem &*verify&~=&~not_blind/*&<&'options'&>

 .cindex "verifying" "not blind"
 .cindex "bcc recipients, verifying none"
 This condition checks that there are no blind (bcc) recipients in the message.
 .cindex "verifying" "not blind"
 .cindex "bcc recipients, verifying none"
 This condition checks that there are no blind (bcc) recipients in the message.


@@ -30852,6 +30880,11 @@ case-sensitively; domains are checked case-insensitively. If &'Resent-To:'& or
 &'Resent-Cc:'& header lines exist, they are also checked. This condition can be
 used only in a DATA or non-SMTP ACL.
 
 &'Resent-Cc:'& header lines exist, they are also checked. This condition can be
 used only in a DATA or non-SMTP ACL.
 

+.new
+There is one possible option, &`case_insensitive`&.  If this is present then
+local parts are checked case-insensitively.
+.wen
+

 There are, of course, many legitimate messages that make use of blind (bcc)
 recipients. This check should not be used on its own for blocking messages.
 
 There are, of course, many legitimate messages that make use of blind (bcc)
 recipients. This check should not be used on its own for blocking messages.
 


@@ -37702,6 +37735,11 @@ Match only frozen messages.
 
 .vitem &*-x*&
 Match only non-frozen messages.
 
 .vitem &*-x*&
 Match only non-frozen messages.

+
+.new
+.vitem &*-G*&&~<&'queuename'&>
+Match only messages in the given queue.  Without this, the default queue is searched.
+.wen

 .endlist
 
 The following options control the format of the output:
 .endlist
 
 The following options control the format of the output: