Expansions: Reduce memory use of ${listcount }

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index d981f623019a4c2fa7f7610ca392232a810365e1..2938de5761645f7fc7fcf229e43d9f98683405c2 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -1394,9 +1394,22 @@ Again, cutthrough delivery counts as a verification.
 .next
 Individual routers can be explicitly skipped when running the routers to
 check an address given in the SMTP EXPN command (see the &%expn%& option).
 .next
 Individual routers can be explicitly skipped when running the routers to
 check an address given in the SMTP EXPN command (see the &%expn%& option).

+

 .next
 If the &%domains%& option is set, the domain of the address must be in the set
 of domains that it defines.
 .next
 If the &%domains%& option is set, the domain of the address must be in the set
 of domains that it defines.

+.new
+.cindex "tainted data" "de-tainting"
+A match verifies the variable &$domain$& (which carries tainted data)
+and assigns an untainted value to the &$domain_data$& variable.
+Such an untainted value is often needed in the transport.
+For specifics of the matching operation and the resulting untainted value,
+refer to section &<<SECTdomainlist>>&.
+
+When an untainted value is wanted, use this option
+rather than the generic &%condition%& option.
+.wen
+

 .next
 .vindex "&$local_part_prefix$&"
 .vindex "&$local_part_prefix_v$&"
 .next
 .vindex "&$local_part_prefix$&"
 .vindex "&$local_part_prefix_v$&"


@@ -1405,13 +1418,26 @@ of domains that it defines.
 .vindex "&$local_part_suffix_v$&"
 .cindex affix "router precondition"
 If the &%local_parts%& option is set, the local part of the address must be in
 .vindex "&$local_part_suffix_v$&"
 .cindex affix "router precondition"
 If the &%local_parts%& option is set, the local part of the address must be in

-the set of local parts that it defines. If &%local_part_prefix%& or
+the set of local parts that it defines.
+.new
+A match verifies the variable &$local_part$& (which carries tainted data)
+and assigns an untainted value to the &$local_part_data$& variable.
+Such an untainted value is often needed in the transport.
+For specifics of the matching operation and the resulting untainted value,
+refer to section &<<SECTlocparlis>>&.
+
+When an untainted value is wanted, use this option
+rather than the generic &%condition%& option.
+.wen
+
+If &%local_part_prefix%& or

 &%local_part_suffix%& is in use, the prefix or suffix is removed from the local
 part before this check. If you want to do precondition tests on local parts
 that include affixes, you can do so by using a &%condition%& option (see below)
 that uses the variables &$local_part$&, &$local_part_prefix$&,
 &$local_part_prefix_v$&, &$local_part_suffix$&
 and &$local_part_suffix_v$& as necessary.
 &%local_part_suffix%& is in use, the prefix or suffix is removed from the local
 part before this check. If you want to do precondition tests on local parts
 that include affixes, you can do so by using a &%condition%& option (see below)
 that uses the variables &$local_part$&, &$local_part_prefix$&,
 &$local_part_prefix_v$&, &$local_part_suffix$&
 and &$local_part_suffix_v$& as necessary.

+

 .next
 .vindex "&$local_user_uid$&"
 .vindex "&$local_user_gid$&"
 .next
 .vindex "&$local_user_uid$&"
 .vindex "&$local_user_gid$&"


@@ -1421,23 +1447,37 @@ an account on the local host. If this check succeeds, the uid and gid of the
 local user are placed in &$local_user_uid$& and &$local_user_gid$& and the
 user's home directory is placed in &$home$&; these values can be used in the
 remaining preconditions.
 local user are placed in &$local_user_uid$& and &$local_user_gid$& and the
 user's home directory is placed in &$home$&; these values can be used in the
 remaining preconditions.

+

 .next
 If the &%router_home_directory%& option is set, it is expanded at this point,
 because it overrides the value of &$home$&. If this expansion were left till
 later, the value of &$home$& as set by &%check_local_user%& would be used in
 subsequent tests. Having two different values of &$home$& in the same router
 could lead to confusion.
 .next
 If the &%router_home_directory%& option is set, it is expanded at this point,
 because it overrides the value of &$home$&. If this expansion were left till
 later, the value of &$home$& as set by &%check_local_user%& would be used in
 subsequent tests. Having two different values of &$home$& in the same router
 could lead to confusion.

+

 .next
 If the &%senders%& option is set, the envelope sender address must be in the
 set of addresses that it defines.
 .next
 If the &%senders%& option is set, the envelope sender address must be in the
 set of addresses that it defines.

+

 .next
 If the &%require_files%& option is set, the existence or non-existence of
 specified files is tested.
 .next
 If the &%require_files%& option is set, the existence or non-existence of
 specified files is tested.

+

 .next
 .cindex "customizing" "precondition"
 If the &%condition%& option is set, it is evaluated and tested. This option
 uses an expanded string to allow you to set up your own custom preconditions.
 Expanded strings are described in chapter &<<CHAPexpand>>&.
 .next
 .cindex "customizing" "precondition"
 If the &%condition%& option is set, it is evaluated and tested. This option
 uses an expanded string to allow you to set up your own custom preconditions.
 Expanded strings are described in chapter &<<CHAPexpand>>&.

+
+.new
+Note that while using
+this option for address matching technically works,
+it does not set any de-tainted values.
+Such values are often needed, either for router-specific options or
+for transport options.
+Using the &%domains%& and &%local_parts%& options is usually the most
+convenient way to obtain them.
+.wen

 .endlist
 
 
 .endlist
 
 


@@ -3845,7 +3885,9 @@ id, and the remaining ones must be email addresses. However, if the message is
 active (in the middle of a delivery attempt), it is not altered. This option
 can be used only by an admin user.
 
 active (in the middle of a delivery attempt), it is not altered. This option
 can be used only by an admin user.
 

-.vitem "&%-MC%&&~<&'transport'&>&~<&'hostname'&>&~<&'sequence&~number'&>&&&
+.vitem "&%-MC%&&~<&'transport'&>&~<&'hostname'&>&&&
+       &~<&'host&~IP'&>&&&
+       &~<&'sequence&~number'&>&&&

         &~<&'message&~id'&>"
 .oindex "&%-MC%&"
 .cindex "SMTP" "passed connection"
         &~<&'message&~id'&>"
 .oindex "&%-MC%&"
 .cindex "SMTP" "passed connection"


@@ -3922,6 +3964,18 @@ This option is not intended for use by external callers. It is used internally
 by Exim in conjunction with the &%-MC%& option, and passes on the fact that the
 host to which Exim is connected supports TLS encryption.
 
 by Exim in conjunction with the &%-MC%& option, and passes on the fact that the
 host to which Exim is connected supports TLS encryption.
 

+.new
+.vitem &%-MCr%&&~<&'SNI'&> &&&
+       &%-MCs%&&~<&'SNI'&>
+.oindex "&%-MCs%&"
+.oindex "&%-MCr%&"
+These options are not intended for use by external callers. It is used internally
+by Exim in conjunction with the &%-MCt%& option, and passes on the fact that
+a TLS Server Name Indication was sent as part of the channel establishment.
+The argument gives the SNI string.
+The "r" variant indicates a DANE-verified connection.
+.wen
+

 .vitem &%-MCt%&&~<&'IP&~address'&>&~<&'port'&>&~<&'cipher'&>
 .oindex "&%-MCt%&"
 This option is not intended for use by external callers. It is used internally
 .vitem &%-MCt%&&~<&'IP&~address'&>&~<&'port'&>&~<&'cipher'&>
 .oindex "&%-MCt%&"
 This option is not intended for use by external callers. It is used internally


@@ -6692,11 +6746,11 @@ causes a second lookup to occur.
 The lookup type may optionally be followed by a comma
 and a comma-separated list of options.
 Each option is a &"name=value"& pair.
 The lookup type may optionally be followed by a comma
 and a comma-separated list of options.
 Each option is a &"name=value"& pair.

-Whether an option is meaningful depands on the lookup type.
+Whether an option is meaningful depends on the lookup type.

 
 All lookups support the option &"cache=no_rd"&.
 If this is given then the cache that Exim manages for lookup results
 
 All lookups support the option &"cache=no_rd"&.
 If this is given then the cache that Exim manages for lookup results

-is not checked before diong the lookup.
+is not checked before doing the lookup.

 The result of the lookup is still written to the cache.
 .wen
 
 The result of the lookup is still written to the cache.
 .wen
 


@@ -8416,7 +8470,10 @@ will store a result in the &$host_data$& variable.
 A &%local_parts%& router option or &%local_parts%& ACL condition
 will store a result in the &$local_part_data$& variable.
 .vitem domains
 A &%local_parts%& router option or &%local_parts%& ACL condition
 will store a result in the &$local_part_data$& variable.
 .vitem domains

+.new

 A &%domains%& router option or &%domains%& ACL condition
 A &%domains%& router option or &%domains%& ACL condition

+will store a result in the &$domain_data$& variable
+.wen

 .vitem senders
 A &%senders%& router option or &%senders%& ACL condition
 will store a result in the &$sender_data$& variable.
 .vitem senders
 A &%senders%& router option or &%senders%& ACL condition
 will store a result in the &$sender_data$& variable.


@@ -9451,6 +9508,9 @@ become case-sensitive after &"+caseful"& has been seen.
 .section "Local part lists" "SECTlocparlis"
 .cindex "list" "local part list"
 .cindex "local part" "list"
 .section "Local part lists" "SECTlocparlis"
 .cindex "list" "local part list"
 .cindex "local part" "list"

+These behave in the same way as domain and host lists, with the following
+changes:
+

 Case-sensitivity in local part lists is handled in the same way as for address
 lists, as just described. The &"+caseful"& item can be used if required. In a
 setting of the &%local_parts%& option in a router with &%caseful_local_part%&
 Case-sensitivity in local part lists is handled in the same way as for address
 lists, as just described. The &"+caseful"& item can be used if required. In a
 setting of the &%local_parts%& option in a router with &%caseful_local_part%&


@@ -9498,7 +9558,9 @@ reasons,
 .cindex "tainted data" definition
 .cindex expansion "tainted data"
 and expansion of data deriving from the sender (&"tainted data"&)
 .cindex "tainted data" definition
 .cindex expansion "tainted data"
 and expansion of data deriving from the sender (&"tainted data"&)

-is not permitted.
+.new
+is not permitted (including acessing a file using a tainted name).
+.wen

 
 .new
 Common ways of obtaining untainted equivalents of variables with
 
 .new
 Common ways of obtaining untainted equivalents of variables with


@@ -10087,7 +10149,7 @@ newline at the very end. For the &%header%& and &%bheader%& expansion, for
 those headers that contain lists of addresses, a comma is also inserted at the
 junctions between headers. This does not happen for the &%rheader%& expansion.
 
 those headers that contain lists of addresses, a comma is also inserted at the
 junctions between headers. This does not happen for the &%rheader%& expansion.
 

-.cindex "tainted data"
+.cindex "tainted data" "message headers"

 When the headers are from an incoming message,
 the result of expanding any of these variables is tainted.
 
 When the headers are from an incoming message,
 the result of expanding any of these variables is tainted.
 


@@ -13643,7 +13705,11 @@ filter file to set values that can be tested in users' filter files. For
 example, a system filter could set a value indicating how likely it is that a
 message is junk mail.
 
 example, a system filter could set a value indicating how likely it is that a
 message is junk mail.
 

-.vitem &$spam_$&&'xxx'&
+.vitem &$spam_score$& &&&
+       &$spam_score_int$& &&&
+       &$spam_bar$& &&&
+       &$spam_report$& &&&
+       &$spam_action$&

 A number of variables whose names start with &$spam$& are available when Exim
 is compiled with the content-scanning extension. For details, see section
 &<<SECTscanspamass>>&.
 A number of variables whose names start with &$spam$& are available when Exim
 is compiled with the content-scanning extension. For details, see section
 &<<SECTscanspamass>>&.


@@ -14033,6 +14099,10 @@ 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.
 
 option to a true value. To avoid breaking existing installations, it
 defaults to false.
 

+.new
+&*Note*&: This is entirely separate from Exim's tainted-data tracking.
+.wen
+

 
 .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


@@ -14665,6 +14735,7 @@ listed in more than one group.
 .row &%local_scan_timeout%&          "timeout for &[local_scan()]&"
 .row &%message_size_limit%&          "for all messages"
 .row &%percent_hack_domains%&        "recognize %-hack for these domains"
 .row &%local_scan_timeout%&          "timeout for &[local_scan()]&"
 .row &%message_size_limit%&          "for all messages"
 .row &%percent_hack_domains%&        "recognize %-hack for these domains"

+.row &%proxy_protocol_timeout%&      "timeout for proxy protocol negotiation"

 .row &%spamd_address%&               "set interface to SpamAssassin"
 .row &%strict_acl_vars%&             "object to unset ACL variables"
 .row &%spf_smtp_comment_template%&   "template for &$spf_smtp_comment$&"
 .row &%spamd_address%&               "set interface to SpamAssassin"
 .row &%strict_acl_vars%&             "object to unset ACL variables"
 .row &%spf_smtp_comment_template%&   "template for &$spf_smtp_comment$&"


@@ -16912,7 +16983,7 @@ not count as protocol errors (see &%smtp_max_synprot_errors%&).
 .option pipelining_connect_advertise_hosts main "host list&!!" *
 .cindex "pipelining" "early connection"
 .cindex "pipelining" PIPE_CONNECT
 .option pipelining_connect_advertise_hosts main "host list&!!" *
 .cindex "pipelining" "early connection"
 .cindex "pipelining" PIPE_CONNECT

-.cindex "ESMTP extensions" X_PIPE_CONNECT
+.cindex "ESMTP extensions" PIPE_CONNECT

 If Exim is built with the SUPPORT_PIPE_CONNECT build option
 this option controls which hosts the facility is advertised to
 and from which pipeline early-connection (before MAIL) SMTP
 If Exim is built with the SUPPORT_PIPE_CONNECT build option
 this option controls which hosts the facility is advertised to
 and from which pipeline early-connection (before MAIL) SMTP


@@ -16921,7 +16992,9 @@ When used, the pipelining saves on roundtrip times.
 
 See also the &%hosts_pipe_connect%& smtp transport option.
 
 
 See also the &%hosts_pipe_connect%& smtp transport option.
 

-Currently the option name &"X_PIPE_CONNECT"& is used.
+.new
+The SMTP service extension keyword advertised is &"PIPE_CONNECT"&.
+.wen

 
 
 .option prdr_enable main boolean false
 
 
 .option prdr_enable main boolean false


@@ -17002,6 +17075,14 @@ admin user unless &%prod_requires_admin%& is set false. See also
 &%queue_list_requires_admin%& and &%commandline_checks_require_admin%&.
 
 
 &%queue_list_requires_admin%& and &%commandline_checks_require_admin%&.
 
 

+.new
+.option proxy_protocol_timeout main time 3s
+.cindex proxy "proxy protocol"
+This option sets the timeout for proxy protocol negotiation.
+For details see section &<<SECTproxyInbound>>&.
+.wen
+
+

 .option qualify_domain main string "see below"
 .cindex "domain" "for qualifying addresses"
 .cindex "address" "qualification"
 .option qualify_domain main string "see below"
 .cindex "domain" "for qualifying addresses"
 .cindex "address" "qualification"


@@ -17304,6 +17385,9 @@ manager, there is no way of controlling the total number of simultaneous
 deliveries if the configuration allows a delivery attempt as soon as a message
 is received.
 
 deliveries if the configuration allows a delivery attempt as soon as a message
 is received.
 

+See also the &%max_parallel%& generic transport option,
+and the &%serialize_hosts%& smtp transport option.
+

 .cindex "number of deliveries"
 .cindex "delivery" "maximum number of"
 If you want to control the total number of deliveries on the system, you
 .cindex "number of deliveries"
 .cindex "delivery" "maximum number of"
 If you want to control the total number of deliveries on the system, you


@@ -18462,7 +18546,9 @@ than the public cert of individual clients.  With both OpenSSL and GnuTLS, if
 the value is a file then the certificates are sent by Exim as a server to
 connecting clients, defining the list of accepted certificate authorities.
 Thus the values defined should be considered public data.  To avoid this,
 the value is a file then the certificates are sent by Exim as a server to
 connecting clients, defining the list of accepted certificate authorities.
 Thus the values defined should be considered public data.  To avoid this,

-use the explicit directory version.
+use the explicit directory version. (If your peer is Exim up to 4.85,
+using GnuTLS, you may need to send the CAs (thus using the file
+variant). Otherwise the peer doesn't send its certificate.)

 
 See &<<SECTtlssni>>& for discussion of when this option might be re-expanded.
 
 
 See &<<SECTtlssni>>& for discussion of when this option might be re-expanded.
 


@@ -18781,7 +18867,10 @@ address (with affixes removed if relevant) is the name of an account on the
 local system. The check is done by calling the &[getpwnam()]& function rather
 than trying to read &_/etc/passwd_& directly. This means that other methods of
 holding password data (such as NIS) are supported. If the local part is a local
 local system. The check is done by calling the &[getpwnam()]& function rather
 than trying to read &_/etc/passwd_& directly. This means that other methods of
 holding password data (such as NIS) are supported. If the local part is a local

-user, &$home$& is set from the password data, and can be tested in other
+user,
+.cindex "tainted data" "de-tainting"
+&$local_part_data$& is set to an untainted version of the local part and
+&$home$& is set from the password data. The latter can be tested in other

 preconditions that are evaluated after this one (the order of evaluation is
 given in section &<<SECTrouprecon>>&). However, the value of &$home$& can be
 overridden by &%router_home_directory%&. If the local part is not a local user,
 preconditions that are evaluated after this one (the order of evaluation is
 given in section &<<SECTrouprecon>>&). However, the value of &$home$& can be
 overridden by &%router_home_directory%&. If the local part is not a local user,


@@ -18928,7 +19017,8 @@ This applies to all of the SRV, MX, AAAA, A lookup sequence.
 If this option is set, the router is skipped unless the current domain matches
 the list. If the match is achieved by means of a file lookup, the data that the
 lookup returned for the domain is placed in &$domain_data$& for use in string
 If this option is set, the router is skipped unless the current domain matches
 the list. If the match is achieved by means of a file lookup, the data that the
 lookup returned for the domain is placed in &$domain_data$& for use in string

-expansions of the driver's private options. See section &<<SECTrouprecon>>& for
+expansions of the driver's private options and in the transport.
+See section &<<SECTrouprecon>>& for

 a list of the order in which preconditions are evaluated.
 
 
 a list of the order in which preconditions are evaluated.
 
 


@@ -19291,12 +19381,13 @@ section &<<SECTlocparlis>>& for a discussion of local part lists. Because the
 string is expanded, it is possible to make it depend on the domain, for
 example:
 .code
 string is expanded, it is possible to make it depend on the domain, for
 example:
 .code

-local_parts = dbm;/usr/local/specials/$domain
+local_parts = dbm;/usr/local/specials/$domain_data

 .endd
 .vindex "&$local_part_data$&"
 If the match is achieved by a lookup, the data that the lookup returned
 for the local part is placed in the variable &$local_part_data$& for use in
 .endd
 .vindex "&$local_part_data$&"
 If the match is achieved by a lookup, the data that the lookup returned
 for the local part is placed in the variable &$local_part_data$& for use in

-expansions of the router's private options. You might use this option, for
+expansions of the router's private options or in the transport.
+You might use this option, for

 example, if you have a large number of local virtual domains, and you want to
 send all postmaster mail to the same place without having to set up an alias in
 each virtual domain:
 example, if you have a large number of local virtual domains, and you want to
 send all postmaster mail to the same place without having to set up an alias in
 each virtual domain:


@@ -19641,6 +19732,10 @@ Values containing a list-separator should have them doubled.
 When a router runs, the strings are evaluated in order,
 to create variables which are added to the set associated with
 the address.
 When a router runs, the strings are evaluated in order,
 to create variables which are added to the set associated with
 the address.

+.new
+This is done immediately after all the preconditions, before the
+evaluation of the &%address_data%& option.
+.wen

 The variable is set with the expansion of the value.
 The variables can be used by the router options
 (not including any preconditions)
 The variable is set with the expansion of the value.
 The variables can be used by the router options
 (not including any preconditions)


@@ -25016,12 +25111,14 @@ authenticated as a client.
 
 
 .option command_timeout smtp time 5m
 
 
 .option command_timeout smtp time 5m

+.cindex timeout "smtp transport command"

 This sets a timeout for receiving a response to an SMTP command that has been
 sent out. It is also used when waiting for the initial banner line from the
 remote host. Its value must not be zero.
 
 
 .option connect_timeout smtp time 5m
 This sets a timeout for receiving a response to an SMTP command that has been
 sent out. It is also used when waiting for the initial banner line from the
 remote host. Its value must not be zero.
 
 
 .option connect_timeout smtp time 5m

+.cindex timeout "smtp transport connect"

 This sets a timeout for the &[connect()]& function, which sets up a TCP/IP call
 to a remote host. A setting of zero allows the system timeout (typically
 several minutes) to act. To have any effect, the value of this option must be
 This sets a timeout for the &[connect()]& function, which sets up a TCP/IP call
 to a remote host. A setting of zero allows the system timeout (typically
 several minutes) to act. To have any effect, the value of this option must be


@@ -25057,6 +25154,7 @@ be treated as unset and &%tls_require_ciphers%& will be used instead.
 
 
 .option data_timeout smtp time 5m
 
 
 .option data_timeout smtp time 5m

+.cindex timeout "for transmitted SMTP data blocks"

 This sets a timeout for the transmission of each block in the data portion of
 the message. As a result, the overall timeout for a message depends on the size
 of the message. Its value must not be zero. See also &%final_timeout%&.
 This sets a timeout for the transmission of each block in the data portion of
 the message. As a result, the overall timeout for a message depends on the size
 of the message. Its value must not be zero. See also &%final_timeout%&.


@@ -25195,6 +25293,7 @@ fails"& facility.
 
 
 .option final_timeout smtp time 10m
 
 
 .option final_timeout smtp time 10m

+.cindex timeout "for transmitted SMTP data accept"

 This is the timeout that applies while waiting for the response to the final
 line containing just &"."& that terminates a message. Its value must not be
 zero.
 This is the timeout that applies while waiting for the response to the final
 line containing just &"."& that terminates a message. Its value must not be
 zero.


@@ -25441,9 +25540,12 @@ incoming messages, use an appropriate ACL.
 .cindex "authentication" "optional in client"
 This option provides a list of servers to which, provided they announce
 authentication support, Exim will attempt to authenticate as a client when it
 .cindex "authentication" "optional in client"
 This option provides a list of servers to which, provided they announce
 authentication support, Exim will attempt to authenticate as a client when it

-connects. If authentication fails, Exim will try to transfer the message
-unauthenticated. See also &%hosts_require_auth%&, and chapter
-&<<CHAPSMTPAUTH>>& for details of authentication.
+connects. If authentication fails
+.new
+and &%hosts_require_auth%& permits,
+.wen
+Exim will try to transfer the message unauthenticated.
+See also chapter &<<CHAPSMTPAUTH>>& for details of authentication.

 
 .option hosts_try_chunking smtp "host list&!!" *
 .cindex CHUNKING "enabling, in client"
 
 .option hosts_try_chunking smtp "host list&!!" *
 .cindex CHUNKING "enabling, in client"


@@ -25576,6 +25678,12 @@ It is expanded per-address and can depend on any of
 &$address_data$&, &$domain_data$&, &$local_part_data$&,
 &$host$&, &$host_address$& and &$host_port$&.
 
 &$address_data$&, &$domain_data$&, &$local_part_data$&,
 &$host$&, &$host_address$& and &$host_port$&.
 

+.new
+If the connection is DANE-enabled then this option is ignored;
+only messages having the domain used for the DANE TLSA lookup are
+sent on the connection.
+.wen
+

 .option port smtp string&!! "see below"
 .cindex "port" "sending TCP/IP"
 .cindex "TCP/IP" "setting outgoing port"
 .option port smtp string&!! "see below"
 .cindex "port" "sending TCP/IP"
 .cindex "TCP/IP" "setting outgoing port"


@@ -25758,7 +25866,11 @@ See &<<SECTresumption>>& for details.
 .cindex "TLS" SNI
 .cindex SNI "setting in client"
 .vindex "&$tls_sni$&"
 .cindex "TLS" SNI
 .cindex SNI "setting in client"
 .vindex "&$tls_sni$&"

-If this option is set then it sets the $tls_out_sni variable and causes any
+If this option is set
+.new
+and the connection is not DANE-validated
+.wen
+then it sets the $tls_out_sni variable and causes any

 TLS session to pass this value as the Server Name Indication extension to
 the remote side, which can be used by the remote side to select an appropriate
 certificate and private key for the session.
 TLS session to pass this value as the Server Name Indication extension to
 the remote side, which can be used by the remote side to select an appropriate
 certificate and private key for the session.


@@ -27262,7 +27374,7 @@ conditions:
 .ilist
 The client host must match &%auth_advertise_hosts%& (default *).
 .next
 .ilist
 The client host must match &%auth_advertise_hosts%& (default *).
 .next

-It the &%server_advertise_condition%& option is set, its expansion must not
+If the &%server_advertise_condition%& option is set, its expansion must not

 yield the empty string, &"0"&, &"no"&, or &"false"&.
 .endlist
 
 yield the empty string, &"0"&, &"no"&, or &"false"&.
 .endlist
 


@@ -27370,7 +27482,7 @@ encode '\0user@domain.com\0pas$$word'
 .endd
 gives an incorrect answer because of the unescaped &"@"& and &"$"& characters.
 
 .endd
 gives an incorrect answer because of the unescaped &"@"& and &"$"& characters.
 

-If you have the &%mimencode%& command installed, another way to do produce
+If you have the &%mimencode%& command installed, another way to produce

 base64-encoded strings is to run the command
 .code
 echo -e -n `\0user\0password' | mimencode
 base64-encoded strings is to run the command
 .code
 echo -e -n `\0user\0password' | mimencode


@@ -28764,6 +28876,12 @@ Some other recently added features may only be available in one or the other.
 This should be documented with the feature.  If the documentation does not
 explicitly state that the feature is infeasible in the other TLS
 implementation, then patches are welcome.
 This should be documented with the feature.  If the documentation does not
 explicitly state that the feature is infeasible in the other TLS
 implementation, then patches are welcome.

+.new
+.next
+The output from "exim -bV" will show which (if any) support was included
+in the build.
+Also, the macro "_HAVE_OPENSSL" or "_HAVE_GNUTLS" will be defined.
+.wen

 .endlist
 
 
 .endlist
 
 


@@ -29237,6 +29355,61 @@ There is no current way to staple a proof for a client certificate.
 .endd
 
 
 .endd
 
 

+.new
+.section "Caching of static server configuration items" "SECTserverTLScache"
+.cindex certificate caching
+.cindex privatekey caching
+.cindex crl caching
+.cindex ocsp caching
+.cindex ciphers caching
+.cindex "CA bundle" caching
+.cindex "certificate authorities" caching
+.cindex tls_certificate caching
+.cindex tls_privatekey caching
+.cindex tls_crl caching
+.cindex tls_ocsp_file caching
+.cindex tls_require_ciphers caching
+.cindex tls_verify_certificate caching
+.cindex caching certificate
+.cindex caching privatekey
+.cindex caching crl
+.cindex caching ocsp
+.cindex caching ciphers
+.cindex caching "certificate authorities
+If any of the main configuration options &%tls_certificate%&, &%tls_privatekey%&,
+&%tls_crl%& and &%tls_ocsp_file%& have values with no
+expandable elements,
+then the associated information is loaded at daemon startup.
+It is made available
+to child processes forked for handling received SMTP connections.
+
+This caching is currently only supported under Linux and FreeBSD.
+
+If caching is not possible, for example if an item has to be dependent
+on the peer host so contains a &$sender_host_name$& expansion, the load
+of the associated information is done at the startup of the TLS connection.
+
+The cache is invalidated and reloaded after any changes to the directories
+containing files specified by these options.
+
+The information specified by the main option &%tls_verify_certificates%&
+is similarly cached so long as it specifies files explicitly
+or (under GnuTLS) is the string &"system,cache"&.
+The latter case is not automatically invalidated;
+it is the operator's responsibility to arrange for a daemon restart
+any time the system certificate authority bundle is updated.
+A HUP signal is sufficient for this.
+The value &"system"& results in no caching under GnuTLS.
+
+The macro _HAVE_TLS_CA_CACHE will be defined if the suffix for "system"
+is acceptable in configurations for the Exim executavble.
+
+Caching of the system Certificate Authorities bundle can
+save siginificant time and processing on every TLS connection
+accepted by Exim.
+.wen
+
+

 
 
 .section "Configuring an Exim client to use TLS" "SECTclientTLS"
 
 
 .section "Configuring an Exim client to use TLS" "SECTclientTLS"


@@ -29277,7 +29450,10 @@ unencrypted.
 
 The &%tls_certificate%& and &%tls_privatekey%& options of the &(smtp)&
 transport provide the client with a certificate, which is passed to the server
 
 The &%tls_certificate%& and &%tls_privatekey%& options of the &(smtp)&
 transport provide the client with a certificate, which is passed to the server

-if it requests it. If the server is Exim, it will request a certificate only if
+if it requests it.
+This is an optional thing for TLS connections, although either end
+may insist on it.
+If the server is Exim, it will request a certificate only if

 &%tls_verify_hosts%& or &%tls_try_verify_hosts%& matches the client.
 
 &*Note*&: Do not use a certificate which has the OCSP-must-staple extension,
 &%tls_verify_hosts%& or &%tls_try_verify_hosts%& matches the client.
 
 &*Note*&: Do not use a certificate which has the OCSP-must-staple extension,


@@ -29357,6 +29533,62 @@ outgoing connection.
 
 
 
 
 
 

+.new
+.section "Caching of static client configuration items" "SECTclientTLScache"
+.cindex certificate caching
+.cindex privatekey caching
+.cindex crl caching
+.cindex ciphers caching
+.cindex "CA bundle" caching
+.cindex "certificate authorities" caching
+.cindex tls_certificate caching
+.cindex tls_privatekey caching
+.cindex tls_crl caching
+.cindex tls_require_ciphers caching
+.cindex tls_verify_certificate caching
+.cindex caching certificate
+.cindex caching privatekey
+.cindex caching crl
+.cindex caching ciphers
+.cindex caching "certificate authorities
+If any of the transport configuration options &%tls_certificate%&, &%tls_privatekey%&
+and &%tls_crl%& have values with no
+expandable elements,
+then the associated information is loaded per smtp transport
+at daemon startup, at the start of a queue run, or on a
+command-line specified message delivery.
+It is made available
+to child processes forked for handling making SMTP connections.
+
+This caching is currently only supported under Linux.
+
+If caching is not possible, the load
+of the associated information is done at the startup of the TLS connection.
+
+The cache is invalidated in the daemon
+and reloaded after any changes to the directories
+containing files specified by these options.
+
+The information specified by the main option &%tls_verify_certificates%&
+is similarly cached so long as it specifies files explicitly
+or (under GnuTLS) is the string &"system,cache"&.
+The latter case is not automatically invaludated;
+it is the operator's responsibility to arrange for a daemon restart
+any time the system certificate authority bundle is updated.
+A HUP signal is sufficient for this.
+The value &"system"& results in no caching under GnuTLS.
+
+The macro _HAVE_TLS_CA_CACHE will be defined if the suffix for "system"
+is acceptable in configurations for the Exim executavble.
+
+Caching of the system Certificate Authorities bundle can
+save siginificant time and processing on every TLS connection
+initiated by Exim.
+.wen
+
+
+
+

 .section "Use of TLS Server Name Indication" "SECTtlssni"
 .cindex "TLS" "Server Name Indication"
 .cindex "TLS" SNI
 .section "Use of TLS Server Name Indication" "SECTtlssni"
 .cindex "TLS" "Server Name Indication"
 .cindex "TLS" SNI


@@ -29392,6 +29624,11 @@ nothing more to it.  Choosing a sensible value not derived insecurely is the
 only point of caution.  The &$tls_out_sni$& variable will be set to this string
 for the lifetime of the client connection (including during authentication).
 
 only point of caution.  The &$tls_out_sni$& variable will be set to this string
 for the lifetime of the client connection (including during authentication).
 

+.new
+If DANE validated the connection attempt then the value of the &%tls_sni%& option
+is forced to the domain part of the recipient address.
+.wen
+

 Except during SMTP client sessions, if &$tls_in_sni$& is set then it is a string
 received from a client.
 It can be logged with the &%log_selector%& item &`+tls_sni`&.
 Except during SMTP client sessions, if &$tls_in_sni$& is set then it is a string
 received from a client.
 It can be logged with the &%log_selector%& item &`+tls_sni`&.


@@ -29689,7 +29926,7 @@ by (a) is thought to be smaller than that of the set of root CAs.
 It also allows the server to declare (implicitly) that connections to it should use TLS.  An MITM could simply
 fail to pass on a server's STARTTLS.
 
 It also allows the server to declare (implicitly) that connections to it should use TLS.  An MITM could simply
 fail to pass on a server's STARTTLS.
 

-DANE scales better than having to maintain (and side-channel communicate) copies of server certificates
+DANE scales better than having to maintain (and communicate via side-channel) copies of server certificates

 for every possible target server.  It also scales (slightly) better than having to maintain on an SMTP
 client a copy of the standard CAs bundle.  It also means not having to pay a CA for certificates.
 
 for every possible target server.  It also scales (slightly) better than having to maintain on an SMTP
 client a copy of the standard CAs bundle.  It also means not having to pay a CA for certificates.
 


@@ -29834,6 +30071,7 @@ If DANE is requested and useable (see above) the following transport options are
   tls_verify_certificates
   tls_crl
   tls_verify_cert_hostnames
   tls_verify_certificates
   tls_crl
   tls_verify_cert_hostnames

+  tls_sni

 .endd
 
 If DANE is not usable, whether requested or not, and CA-anchored
 .endd
 
 If DANE is not usable, whether requested or not, and CA-anchored


@@ -32577,7 +32815,7 @@ in kilobytes, megabytes, or gigabytes, respectively.
 
 The &%per_rcpt%& option causes Exim to limit the rate at which recipients are
 accepted. It can be used in the &%acl_smtp_rcpt%&, &%acl_smtp_predata%&,
 
 The &%per_rcpt%& option causes Exim to limit the rate at which recipients are
 accepted. It can be used in the &%acl_smtp_rcpt%&, &%acl_smtp_predata%&,

-&%acl_smtp_mime%&, &%acl_smtp_data%&, or &%acl_smtp_rcpt%& ACLs. In
+&%acl_smtp_mime%&, or &%acl_smtp_data%& ACLs. In

 &%acl_smtp_rcpt%& the rate is updated one recipient at a time; in the other
 ACLs the rate is updated with the total (accepted) recipient count in one go. Note that
 in either case the rate limiting engine will see a message with many
 &%acl_smtp_rcpt%& the rate is updated one recipient at a time; in the other
 ACLs the rate is updated with the total (accepted) recipient count in one go. Note that
 in either case the rate limiting engine will see a message with many


@@ -38059,7 +38297,8 @@ fields record the router and transport that were used to process the address.
 If SMTP AUTH was used for the delivery there is an additional item A=
 followed by the name of the authenticator that was used.
 If an authenticated identification was set up by the authenticator's &%client_set_id%&
 If SMTP AUTH was used for the delivery there is an additional item A=
 followed by the name of the authenticator that was used.
 If an authenticated identification was set up by the authenticator's &%client_set_id%&

-option, this is logged too, separated by a colon from the authenticator name.
+option, this is logged too, as a second colon-separated list item.
+Optionally (see the &%smtp_mailauth%& &%log_selector%&) there may be a third list item.

 
 If a shadow transport was run after a successful local delivery, the log line
 for the successful delivery has an item added on the end, of the form
 
 If a shadow transport was run after a successful local delivery, the log line
 for the successful delivery has an item added on the end, of the form


@@ -38441,6 +38680,7 @@ routing email addresses, but it does apply to &"byname"& lookups.
 client's ident port times out.
 .next
 .cindex "log" "incoming interface"
 client's ident port times out.
 .next
 .cindex "log" "incoming interface"

+.cindex "log" "outgoing interface"

 .cindex "log" "local interface"
 .cindex "log" "local address and port"
 .cindex "TCP/IP" "logging local address and port"
 .cindex "log" "local interface"
 .cindex "log" "local address and port"
 .cindex "TCP/IP" "logging local address and port"


@@ -38449,7 +38689,10 @@ client's ident port times out.
 to the &"<="& line as an IP address in square brackets, tagged by I= and
 followed by a colon and the port number. The local interface and port are also
 added to other SMTP log lines, for example, &"SMTP connection from"&, to
 to the &"<="& line as an IP address in square brackets, tagged by I= and
 followed by a colon and the port number. The local interface and port are also
 added to other SMTP log lines, for example, &"SMTP connection from"&, to

-rejection lines, and (despite the name) to outgoing &"=>"& and &"->"& lines.
+rejection lines, and (despite the name) to outgoing
+.new
+&"=>"&, &"->"&, &"=="& and &"**"& lines.
+.wen

 The latter can be disabled by turning off the &%outgoing_interface%& option.
 .next
 .cindex log "incoming proxy address"
 The latter can be disabled by turning off the &%outgoing_interface%& option.
 .next
 .cindex log "incoming proxy address"


@@ -38797,9 +39040,9 @@ the next chapter. The utilities described here are:
   "check address acceptance from given IP"
 .irow &<<SECTdbmbuild>>&      &'exim_dbmbuild'& "build a DBM file"
 .irow &<<SECTfinindret>>&     &'exinext'&       "extract retry information"
   "check address acceptance from given IP"
 .irow &<<SECTdbmbuild>>&      &'exim_dbmbuild'& "build a DBM file"
 .irow &<<SECTfinindret>>&     &'exinext'&       "extract retry information"

-.irow &<<SECThindatmai>>&     &'exim_dumpdb'&   "dump a hints database"
-.irow &<<SECThindatmai>>&     &'exim_tidydb'&   "clean up a hints database"
-.irow &<<SECThindatmai>>&     &'exim_fixdb'&    "patch a hints database"
+.irow &<<SECTdumpdb>>&        &'exim_dumpdb'&   "dump a hints database"
+.irow &<<SECTtidydb>>&        &'exim_tidydb'&   "clean up a hints database"
+.irow &<<SECTfixdb>>&         &'exim_fixdb'&    "patch a hints database"

 .irow &<<SECTmailboxmaint>>&  &'exim_lock'&     "lock a mailbox file"
 .endtable
 
 .irow &<<SECTmailboxmaint>>&  &'exim_lock'&     "lock a mailbox file"
 .endtable
 


@@ -39305,7 +39548,7 @@ in a transport)
 
 
 
 
 
 

-.section "exim_dumpdb" "SECID261"
+.section "exim_dumpdb" "SECTdumpdb"

 .cindex "&'exim_dumpdb'&"
 The entire contents of a database are written to the standard output by the
 &'exim_dumpdb'& program, which has no options or arguments other than the
 .cindex "&'exim_dumpdb'&"
 The entire contents of a database are written to the standard output by the
 &'exim_dumpdb'& program, which has no options or arguments other than the


@@ -39342,7 +39585,7 @@ cross-references.
 
 
 
 
 
 

-.section "exim_tidydb" "SECID262"
+.section "exim_tidydb" "SECTtidydb"

 .cindex "&'exim_tidydb'&"
 The &'exim_tidydb'& utility program is used to tidy up the contents of a hints
 database. If run with no options, it removes all records that are more than 30
 .cindex "&'exim_tidydb'&"
 The &'exim_tidydb'& utility program is used to tidy up the contents of a hints
 database. If run with no options, it removes all records that are more than 30


@@ -39391,7 +39634,7 @@ databases is likely to keep on increasing.
 
 
 
 
 
 

-.section "exim_fixdb" "SECID263"
+.section "exim_fixdb" "SECTfixdb"

 .cindex "&'exim_fixdb'&"
 The &'exim_fixdb'& program is a utility for interactively modifying databases.
 Its main use is for testing Exim, but it might also be occasionally useful for
 .cindex "&'exim_fixdb'&"
 The &'exim_fixdb'& program is a utility for interactively modifying databases.
 Its main use is for testing Exim, but it might also be occasionally useful for


@@ -40777,7 +41020,7 @@ but for EC keys it is the base64 of the pure key; no ASN.1 wrapping.
 Signing is enabled by setting private options on the SMTP transport.
 These options take (expandable) strings as arguments.
 
 Signing is enabled by setting private options on the SMTP transport.
 These options take (expandable) strings as arguments.
 

-.option dkim_domain smtp string list&!! unset
+.option dkim_domain smtp "string list&!!" unset

 The domain(s) you want to sign with.
 After expansion, this can be a list.
 Each element in turn,
 The domain(s) you want to sign with.
 After expansion, this can be a list.
 Each element in turn,


@@ -40787,7 +41030,7 @@ while expanding the remaining signing options.
 If it is empty after expansion, DKIM signing is not done,
 and no error will result even if &%dkim_strict%& is set.
 
 If it is empty after expansion, DKIM signing is not done,
 and no error will result even if &%dkim_strict%& is set.
 

-.option dkim_selector smtp string list&!! unset
+.option dkim_selector smtp "string list&!!" unset

 This sets the key selector string.
 After expansion, which can use &$dkim_domain$&, this can be a list.
 Each element in turn is put in the expansion
 This sets the key selector string.
 After expansion, which can use &$dkim_domain$&, this can be a list.
 Each element in turn is put in the expansion


@@ -41451,7 +41694,7 @@ Example usage:
 .code
   #macro
   SRS_SECRET = <pick something unique for your site for this. Use on all MXs.>
 .code
   #macro
   SRS_SECRET = <pick something unique for your site for this. Use on all MXs.>

-  
+

   #routers
 
   outbound:
   #routers
 
   outbound:


@@ -41461,7 +41704,7 @@ Example usage:
     transport = ${if eq {$local_part@$domain} \
                         {$original_local_part@$original_domain} \
                      {remote_smtp} {remote_forwarded_smtp}}
     transport = ${if eq {$local_part@$domain} \
                         {$original_local_part@$original_domain} \
                      {remote_smtp} {remote_forwarded_smtp}}

-  
+

   inbound_srs:
     driver =    redirect
     senders =   :
   inbound_srs:
     driver =    redirect
     senders =   :


@@ -41469,7 +41712,7 @@ Example usage:
     # detect inbound bounces which are SRS'd, and decode them
     condition = ${if inbound_srs {$local_part} {SRS_SECRET}}
     data =      $srs_recipient
     # detect inbound bounces which are SRS'd, and decode them
     condition = ${if inbound_srs {$local_part} {SRS_SECRET}}
     data =      $srs_recipient

-  
+

   inbound_srs_failure:
     driver =    redirect
     senders =   :
   inbound_srs_failure:
     driver =    redirect
     senders =   :


@@ -41481,7 +41724,7 @@ Example usage:
 
   #... further routers here
 
 
   #... further routers here
 

-  
+

   # transport; should look like the non-forward outbound
   # one, plus the max_rcpt and return_path options
   remote_forwarded_smtp:
   # transport; should look like the non-forward outbound
   # one, plus the max_rcpt and return_path options
   remote_forwarded_smtp:


@@ -41610,7 +41853,7 @@ mean, refer to the DMARC website above.  Valid strings are:
 &'reject      '& The DMARC check failed and the library recommends rejecting the email.
 &'quarantine  '& The DMARC check failed and the library recommends keeping it for further inspection.
 &'none        '& The DMARC check passed and the library recommends no specific action, neutral.
 &'reject      '& The DMARC check failed and the library recommends rejecting the email.
 &'quarantine  '& The DMARC check failed and the library recommends keeping it for further inspection.
 &'none        '& The DMARC check passed and the library recommends no specific action, neutral.

-&'norecord    '& No policy section in the DMARC record for this sender domain.
+&'norecord    '& No policy section in the DMARC record for this RFC5322.From field

 &'nofrom      '& Unable to determine the domain of the sender.
 &'temperror   '& Library error or dns error.
 &'off         '& The DMARC check was disabled for this email.
 &'nofrom      '& Unable to determine the domain of the sender.
 &'temperror   '& Library error or dns error.
 &'off         '& The DMARC check was disabled for this email.


@@ -41774,7 +42017,8 @@ automatically determines which version is in use.
 The Proxy Protocol header is the first data received on a TCP connection
 and is inserted before any TLS-on-connect handshake from the client; Exim
 negotiates TLS between Exim-as-server and the remote client, not between
 The Proxy Protocol header is the first data received on a TCP connection
 and is inserted before any TLS-on-connect handshake from the client; Exim
 negotiates TLS between Exim-as-server and the remote client, not between

-Exim and the proxy server.
+Exim and the proxy server. The Proxy Protocol header must be received
+within &%proxy_protocol_timeout%&, which defaults to 3s.

 
 The following expansion variables are usable
 (&"internal"& and &"external"& here refer to the interfaces
 
 The following expansion variables are usable
 (&"internal"& and &"external"& here refer to the interfaces