Filter xfpt needs new macro too

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index f902fe856b5d1c12a639a38a3c5b99e2ee1fb2d1..9ec45a4ebd3eb176ad0fdeb844c9f81e518d76ac 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -41,16 +41,19 @@
 .book
 
 . /////////////////////////////////////////////////////////////////////////////
 .book
 
 . /////////////////////////////////////////////////////////////////////////////

-. These definitions set some parameters and save some typing. Remember that
-. the <bookinfo> element must also be updated for each new edition.
+. These definitions set some parameters and save some typing.
+. Update the Copyright year (only) when changing content.

 . /////////////////////////////////////////////////////////////////////////////
 
 .set previousversion "4.80"
 . /////////////////////////////////////////////////////////////////////////////
 
 .set previousversion "4.80"

-.set version "4.80"
+.include ./local_params

 
 .set ACL "access control lists (ACLs)"
 .set I   "&nbsp;&nbsp;&nbsp;&nbsp;"
 
 
 .set ACL "access control lists (ACLs)"
 .set I   "&nbsp;&nbsp;&nbsp;&nbsp;"
 

+.macro copyyear
+2012
+.endmacro

 
 . /////////////////////////////////////////////////////////////////////////////
 . Additional xfpt markup used by this document, over and above the default
 
 . /////////////////////////////////////////////////////////////////////////////
 . Additional xfpt markup used by this document, over and above the default


@@ -170,15 +173,18 @@
 <bookinfo>
 <title>Specification of the Exim Mail Transfer Agent</title>
 <titleabbrev>The Exim MTA</titleabbrev>
 <bookinfo>
 <title>Specification of the Exim Mail Transfer Agent</title>
 <titleabbrev>The Exim MTA</titleabbrev>

-<date>17 May 2012</date>
+<date>
+.fulldate
+</date>

 <author><firstname>Exim</firstname><surname>Maintainers</surname></author>
 <authorinitials>EM</authorinitials>
 <revhistory><revision>
 <author><firstname>Exim</firstname><surname>Maintainers</surname></author>
 <authorinitials>EM</authorinitials>
 <revhistory><revision>

-  <revnumber>4.80</revnumber>
-  <date>17 May 2012</date>
+.versiondatexml

   <authorinitials>EM</authorinitials>
 </revision></revhistory>
   <authorinitials>EM</authorinitials>
 </revision></revhistory>

-<copyright><year>2012</year><holder>University of Cambridge</holder></copyright>
+<copyright><year>
+.copyyear
+           </year><holder>University of Cambridge</holder></copyright>

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


@@ -367,7 +373,7 @@ contributors.
 
 .new
 .cindex "documentation"
 
 .new
 .cindex "documentation"

-This edition of the Exim specification applies to version &version; of Exim.
+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.
 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.


@@ -533,10 +539,23 @@ The &_.bz2_& file is usually a lot smaller than the &_.gz_& file.
 .cindex "distribution" "signing details"
 .cindex "distribution" "public key"
 .cindex "public key for signed distribution"
 .cindex "distribution" "signing details"
 .cindex "distribution" "public key"
 .cindex "public key for signed distribution"

-The distributions are currently signed with Nigel Metheringham's GPG key. The
-corresponding public key is available from a number of keyservers, and there is
-also a copy in the file &_nigel-pubkey.asc_&. The signatures for the tar bundles are
-in:
+.new
+The distributions will be PGP signed by an individual key of the Release
+Coordinator.  This key will have a uid containing an email address in the
+&'exim.org'& domain and will have signatures from other people, including
+other Exim maintainers.  We expect that the key will be in the "strong set" of
+PGP keys.  There should be a trust path to that key from Nigel Metheringham's
+PGP key, a version of which can be found in the release directory in the file
+&_nigel-pubkey.asc_&.  All keys used will be available in public keyserver pools,
+such as &'pool.sks-keyservers.net'&.
+
+At time of last update, releases were being made by Phil Pennock and signed with
+key &'0x403043153903637F'&, although that key is expected to be replaced in 2013.
+A trust path from Nigel's key to Phil's can be observed at
+&url(https://www.security.spodhuis.org/exim-trustpath).
+.wen
+
+The signatures for the tar bundles are in:

 .display
 &_exim-n.nn.tar.gz.asc_&
 &_exim-n.nn.tar.bz2.asc_&
 .display
 &_exim-n.nn.tar.gz.asc_&
 &_exim-n.nn.tar.bz2.asc_&


@@ -722,6 +741,7 @@ the Exim documentation, &"spool"& is always used in the first sense.
 .cindex "incorporated code"
 .cindex "regular expressions" "library"
 .cindex "PCRE"
 .cindex "incorporated code"
 .cindex "regular expressions" "library"
 .cindex "PCRE"

+.cindex "OpenDMARC"

 A number of pieces of external code are included in the Exim distribution.
 
 .ilist
 A number of pieces of external code are included in the Exim distribution.
 
 .ilist


@@ -846,6 +866,14 @@ ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 SOFTWARE.
 .endblockquote
 
 SOFTWARE.
 .endblockquote
 

+.next
+.cindex "opendmarc" "acknowledgment"
+The DMARC implementation uses the OpenDMARC library which is Copyrighted by
+The Trusted Domain Project. Portions of Exim source which use OpenDMARC
+derived code are indicated in the respective source files. The full OpenDMARC
+license is provided in the LICENSE.opendmarc file contained in the distributed
+source code.
+

 .next
 Many people have contributed code fragments, some large, some small, that were
 not covered by any specific licence requirements. It is assumed that the
 .next
 Many people have contributed code fragments, some large, some small, that were
 not covered by any specific licence requirements. It is assumed that the


@@ -1348,6 +1376,8 @@ Setting the &%verify%& option actually sets two options, &%verify_sender%& and
 &%verify_recipient%&, which independently control the use of the router for
 sender and recipient verification. You can set these options directly if
 you want a router to be used for only one type of verification.
 &%verify_recipient%&, which independently control the use of the router for
 sender and recipient verification. You can set these options directly if
 you want a router to be used for only one type of verification.

+Note that cutthrough delivery is classed as a recipient verification
+for this purpose.

 .next
 If the &%address_test%& option is set false, the router is skipped when Exim is
 run with the &%-bt%& option to test an address routing. This can be helpful
 .next
 If the &%address_test%& option is set false, the router is skipped when Exim is
 run with the &%-bt%& option to test an address routing. This can be helpful


@@ -1357,6 +1387,7 @@ having to simulate the effect of the scanner.
 .next
 Routers can be designated for use only when verifying an address, as
 opposed to routing it for delivery. The &%verify_only%& option controls this.
 .next
 Routers can be designated for use only when verifying an address, as
 opposed to routing it for delivery. The &%verify_only%& option controls this.

+Again, cutthrough delibery 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).


@@ -1602,7 +1633,7 @@ for only a short time (see &%timeout_frozen_after%& and
 .section "Unpacking" "SECID23"
 Exim is distributed as a gzipped or bzipped tar file which, when unpacked,
 creates a directory with the name of the current release (for example,
 .section "Unpacking" "SECID23"
 Exim is distributed as a gzipped or bzipped tar file which, when unpacked,
 creates a directory with the name of the current release (for example,

-&_exim-&version;_&) into which the following files are placed:
+&_exim-&version()_&) into which the following files are placed:

 
 .table2 140pt
 .irow &_ACKNOWLEDGMENTS_& "contains some acknowledgments"
 
 .table2 140pt
 .irow &_ACKNOWLEDGMENTS_& "contains some acknowledgments"


@@ -2298,7 +2329,7 @@ INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.
 For the utility programs, old versions are renamed by adding the suffix &_.O_&
 to their names. The Exim binary itself, however, is handled differently. It is
 installed under a name that includes the version number and the compile number,
 For the utility programs, old versions are renamed by adding the suffix &_.O_&
 to their names. The Exim binary itself, however, is handled differently. It is
 installed under a name that includes the version number and the compile number,

-for example &_exim-&version;-1_&. The script then arranges for a symbolic link
+for example &_exim-&version()-1_&. The script then arranges for a symbolic link

 called &_exim_& to point to the binary. If you are updating a previous version
 of Exim, the script takes care to ensure that the name &_exim_& is never absent
 from the directory (as seen by other processes).
 called &_exim_& to point to the binary. If you are updating a previous version
 of Exim, the script takes care to ensure that the name &_exim_& is never absent
 from the directory (as seen by other processes).


@@ -4308,7 +4339,7 @@ For compatibility with Sendmail, this option is equivalent to
 It sets the incoming protocol and host name (for trusted callers). The
 host name and its colon can be omitted when only the protocol is to be set.
 Note the Exim already has two private options, &%-pd%& and &%-ps%&, that refer
 It sets the incoming protocol and host name (for trusted callers). The
 host name and its colon can be omitted when only the protocol is to be set.
 Note the Exim already has two private options, &%-pd%& and &%-ps%&, that refer

-to embedded Perl. It is therefore impossible to set a protocol value of &`p`&
+to embedded Perl. It is therefore impossible to set a protocol value of &`d`&

 or &`s`& using this option (but that does not seem a real limitation).
 
 .vitem &%-q%&
 or &`s`& using this option (but that does not seem a real limitation).
 
 .vitem &%-q%&


@@ -8775,12 +8806,12 @@ arguments are assigned to the variables &$acl_arg1$& to &$acl_arg9$& in order.
 Any unused are made empty.  The variable &$acl_narg$& is set to the number of
 arguments.  The named ACL (see chapter &<<CHAPACL>>&) is called
 and may use the variables; if another acl expansion is used the values
 Any unused are made empty.  The variable &$acl_narg$& is set to the number of
 arguments.  The named ACL (see chapter &<<CHAPACL>>&) is called
 and may use the variables; if another acl expansion is used the values

-are overwritten.  If the ACL sets
+are restored after it returns.  If the ACL sets

 a value using a "message =" modifier and returns accept or deny, the value becomes
 the result of the expansion.
 a value using a "message =" modifier and returns accept or deny, the value becomes
 the result of the expansion.

-If no message was set and the ACL returned accept or deny
-the value is an empty string.
-If the ACL returned defer the result is a forced-fail.  Otherwise the expansion fails.
+If no message is set and the ACL returns accept or deny
+the expansion result is an empty string.
+If the ACL returns defer the result is a forced-fail.  Otherwise the expansion fails.

 
 
 .vitem "&*${dlfunc{*&<&'file'&>&*}{*&<&'function'&>&*}{*&<&'arg'&>&*}&&&
 
 
 .vitem "&*${dlfunc{*&<&'file'&>&*}{*&<&'function'&>&*}{*&<&'arg'&>&*}&&&


@@ -9741,6 +9772,16 @@ This operator converts a hex string into one that is base64 encoded. This can
 be useful for processing the output of the MD5 and SHA-1 hashing functions.
 
 
 be useful for processing the output of the MD5 and SHA-1 hashing functions.
 
 

+
+.vitem &*${hexquote:*&<&'string'&>&*}*&
+.cindex "quoting" "hex-encoded unprintable characters"
+.cindex "&%hexquote%& expansion item"
+This operator converts non-printable characters in a string into a hex
+escape form. Byte values between 33 (!) and 126 (~) inclusive are left
+as is, and other byte values are converted to &`\xNN`&, for example a
+byt value 127 is converted to &`\x7f`&.
+
+

 .vitem &*${lc:*&<&'string'&>&*}*&
 .cindex "case forcing in strings"
 .cindex "string" "case forcing"
 .vitem &*${lc:*&<&'string'&>&*}*&
 .cindex "case forcing in strings"
 .cindex "string" "case forcing"


@@ -9907,12 +9948,12 @@ dotted-nibble hexadecimal form.  In both cases, this is the "natural" form
 for DNS.  For example,
 .code
 ${reverse_ip:192.0.2.4}
 for DNS.  For example,
 .code
 ${reverse_ip:192.0.2.4}

-${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
+${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.127}

 .endd
 returns
 .code
 4.2.0.192
 .endd
 returns
 .code
 4.2.0.192

-3.0.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2
+f.7.2.0.0.0.0.c.d.c.b.a.1.0.0.0.9.0.0.0.2.4.c.0.8.b.d.0.1.0.0.2

 .endd
 
 
 .endd
 
 


@@ -10091,7 +10132,7 @@ arguments are assigned to the variables &$acl_arg1$& to &$acl_arg9$& in order.
 Any unused are made empty.  The variable &$acl_narg$& is set to the number of
 arguments.  The named ACL (see chapter &<<CHAPACL>>&) is called
 and may use the variables; if another acl expansion is used the values
 Any unused are made empty.  The variable &$acl_narg$& is set to the number of
 arguments.  The named ACL (see chapter &<<CHAPACL>>&) is called
 and may use the variables; if another acl expansion is used the values

-are overwritten.  If the ACL sets
+are restored after it returns.  If the ACL sets

 a value using a "message =" modifier the variable $value becomes
 the result of the expansion, otherwise it is empty.
 If the ACL returns accept the condition is true; if deny, false.
 a value using a "message =" modifier the variable $value becomes
 the result of the expansion, otherwise it is empty.
 If the ACL returns accept the condition is true; if deny, false.


@@ -10291,6 +10332,8 @@ ${if forany{<, $recipients}{match{$item}{^user3@}}{yes}{no}}
 The value of &$item$& is saved and restored while &*forany*& or &*forall*& is
 being processed, to enable these expansion items to be nested.
 
 The value of &$item$& is saved and restored while &*forany*& or &*forall*& is
 being processed, to enable these expansion items to be nested.
 

+To scan a named list, expand it with the &*listnamed*& operator.
+

 
 .vitem &*ge&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*& &&&
        &*gei&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*&
 
 .vitem &*ge&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*& &&&
        &*gei&~{*&<&'string1'&>&*}{*&<&'string2'&>&*}*&


@@ -10834,6 +10877,16 @@ the value of &$authenticated_id$& is normally the login name of the calling
 process. However, a trusted user can override this by means of the &%-oMai%&
 command line option.
 
 process. However, a trusted user can override this by means of the &%-oMai%&
 command line option.
 

+.vitem &$authenticated_fail_id$&
+.cindex "authentication" "fail" "id"
+.vindex "&$authenticated_fail_id$&"
+When an authentication attempt fails, the variable &$authenticated_fail_id$&
+will contain the failed authentication id. If more than one authentication
+id is attempted, it will contain only the last one. The variable is
+available for processing in the ACL's, generally the quit or notquit ACL.
+A message to a local recipient could still be accepted without requiring
+authentication, which means this variable could also be visible in all of
+the ACL's as well.

 
 
 
 
 
 


@@ -11047,6 +11100,12 @@ inserting the message header line with the given name. Note that the name must
 be terminated by colon or white space, because it may contain a wide variety of
 characters. Note also that braces must &'not'& be used.
 
 be terminated by colon or white space, because it may contain a wide variety of
 characters. Note also that braces must &'not'& be used.
 

+.vitem &$headers_added$&
+.vindex "&$headers_added$&"
+Within an ACL this variable contains the headers added so far by
+the ACL modifier add_header (section &<<SECTaddheadacl>>&).
+The headers are a newline-separated list.
+

 .vitem &$home$&
 .vindex "&$home$&"
 When the &%check_local_user%& option is set for a router, the user's home
 .vitem &$home$&
 .vindex "&$home$&"
 When the &%check_local_user%& option is set for a router, the user's home


@@ -11717,6 +11776,12 @@ envelope sender.
 .vindex "&$return_size_limit$&"
 This is an obsolete name for &$bounce_return_size_limit$&.
 
 .vindex "&$return_size_limit$&"
 This is an obsolete name for &$bounce_return_size_limit$&.
 

+.vitem &$router_name$&
+.cindex "router" "name"
+.cindex "name" "of router"
+.vindex "&$router_name$&"
+During the running of a router this variable contains its name.
+

 .vitem &$runrc$&
 .cindex "return code" "from &%run%& expansion"
 .vindex "&$runrc$&"
 .vitem &$runrc$&
 .cindex "return code" "from &%run%& expansion"
 .vindex "&$runrc$&"


@@ -12171,6 +12236,12 @@ This variable contains the numerical value of the local timezone, for example:
 This variable contains the UTC date and time in &"Zulu"& format, as specified
 by ISO 8601, for example: 20030221154023Z.
 
 This variable contains the UTC date and time in &"Zulu"& format, as specified
 by ISO 8601, for example: 20030221154023Z.
 

+.vitem &$transport_name$&
+.cindex "transport" "name"
+.cindex "name" "of transport"
+.vindex "&$transport_name$&"
+During the running of a transport, this variable contains its name.
+

 .vitem &$value$&
 .vindex "&$value$&"
 This variable contains the result of an expansion lookup, extraction operation,
 .vitem &$value$&
 .vindex "&$value$&"
 This variable contains the result of an expansion lookup, extraction operation,


@@ -13077,6 +13148,8 @@ Those options that undergo string expansion before use are marked with
 .option accept_8bitmime main boolean true
 .cindex "8BITMIME"
 .cindex "8-bit characters"
 .option accept_8bitmime main boolean true
 .cindex "8BITMIME"
 .cindex "8-bit characters"

+.cindex "log" "selectors"
+.cindex "log" "8BITMIME"

 This option causes Exim to send 8BITMIME in its response to an SMTP
 EHLO command, and to accept the BODY= parameter on MAIL commands.
 However, though Exim is 8-bit clean, it is not a protocol converter, and it
 This option causes Exim to send 8BITMIME in its response to an SMTP
 EHLO command, and to accept the BODY= parameter on MAIL commands.
 However, though Exim is 8-bit clean, it is not a protocol converter, and it


@@ -13090,6 +13163,11 @@ A more detailed analysis of the issues is provided by Dan Bernstein:
 &url(http://cr.yp.to/smtp/8bitmime.html)
 .endd
 
 &url(http://cr.yp.to/smtp/8bitmime.html)
 .endd
 

+To log received 8BITMIME status use
+.code
+log_selector = +8bitmime
+.endd
+

 .option acl_not_smtp main string&!! unset
 .cindex "&ACL;" "for non-SMTP messages"
 .cindex "non-SMTP messages" "ACLs for"
 .option acl_not_smtp main string&!! unset
 .cindex "&ACL;" "for non-SMTP messages"
 .cindex "non-SMTP messages" "ACLs for"


@@ -13913,7 +13991,7 @@ This option will let GnuTLS (2.12.0 or later) autoload PKCS11 modules with
 the p11-kit configuration files in &_/etc/pkcs11/modules/_&.
 
 See
 the p11-kit configuration files in &_/etc/pkcs11/modules/_&.
 
 See

-&url(http://www.gnu.org/software/gnutls/manual/gnutls.html#Smart-cards-and-HSMs)
+&url(http://www.gnutls.org/manual/gnutls.html#Smart-cards-and-HSMs)

 for documentation.
 .wen
 
 for documentation.
 .wen
 


@@ -14669,6 +14747,8 @@ Possible options may include:
 .next
 &`no_tlsv1_2`&
 .next
 .next
 &`no_tlsv1_2`&
 .next

+&`safari_ecdhe_ecdsa_bug`&
+.next

 &`single_dh_use`&
 .next
 &`single_ecdh_use`&
 &`single_dh_use`&
 .next
 &`single_ecdh_use`&


@@ -14684,6 +14764,15 @@ Possible options may include:
 &`tls_rollback_bug`&
 .endlist
 
 &`tls_rollback_bug`&
 .endlist
 

+.new
+As an aside, the &`safari_ecdhe_ecdsa_bug`& item is a misnomer and affects
+all clients connecting using the MacOS SecureTransport TLS facility prior
+to MacOS 10.8.4, including email clients.  If you see old MacOS clients failing
+to negotiate TLS then this option value might help, provided that your OpenSSL
+release is new enough to contain this work-around.  This may be a situation
+where you have to upgrade OpenSSL to get buggy clients working.
+.wen
+

 
 .option oracle_servers main "string list" unset
 .cindex "Oracle" "server list"
 
 .option oracle_servers main "string list" unset
 .cindex "Oracle" "server list"


@@ -15947,6 +16036,21 @@ The available primes are:
 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 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,
+whether too large or too small, and there's no provision for the client to
+tell the server what these constraints are.  Thus, as a server operator, you
+need to make an educated guess as to what is most likely to work for your
+userbase.
+
+Some known size constraints suggest that a bit-size in the range 2048 to 2236
+is most likely to maximise interoperability.  The upper bound comes from
+applications using the Mozilla Network Security Services (NSS) library, which
+used to set its &`DH_MAX_P_BITS`& upper-bound to 2236.  This affects many
+mail user agents (MUAs). The lower bound comes from Debian installs of Exim4
+prior to the 4.80 release, as Debian used to patch Exim to raise the minimum
+acceptable bound from 1024 to 2048.
+

 
 .option tls_on_connect_ports main "string list" unset
 This option specifies a list of incoming SSMTP (aka SMTPS) ports that should
 
 .option tls_on_connect_ports main "string list" unset
 This option specifies a list of incoming SSMTP (aka SMTPS) ports that should


@@ -16014,6 +16118,9 @@ use OpenSSL with a directory.
 
 See &<<SECTtlssni>>& for discussion of when this option might be re-expanded.
 
 
 See &<<SECTtlssni>>& for discussion of when this option might be re-expanded.
 

+A forced expansion failure or setting to an empty string is equivalent to
+being unset.
+

 
 .option tls_verify_hosts main "host list&!!" unset
 .cindex "TLS" "client certificate verification"
 
 .option tls_verify_hosts main "host list&!!" unset
 .cindex "TLS" "client certificate verification"


@@ -16380,7 +16487,8 @@ be specified using &%condition%&.
 .option debug_print routers string&!! unset
 .cindex "testing" "variables in drivers"
 If this option is set and debugging is enabled (see the &%-d%& command line
 .option debug_print routers string&!! unset
 .cindex "testing" "variables in drivers"
 If this option is set and debugging is enabled (see the &%-d%& command line

-option), the string is expanded and included in the debugging output.
+option) or in address-testing mode (see the &%-bt%& command line option),
+the string is expanded and included in the debugging output.

 If expansion of the string fails, the error message is written to the debugging
 output, and Exim carries on processing.
 This option is provided to help with checking out the values of variables and
 If expansion of the string fails, the error message is written to the debugging
 output, and Exim carries on processing.
 This option is provided to help with checking out the values of variables and


@@ -16389,6 +16497,7 @@ option appears not to be working, &%debug_print%& can be used to output the
 variables it references. The output happens after checks for &%domains%&,
 &%local_parts%&, and &%check_local_user%& but before any other preconditions
 are tested. A newline is added to the text if it does not end with one.
 variables it references. The output happens after checks for &%domains%&,
 &%local_parts%&, and &%check_local_user%& but before any other preconditions
 are tested. A newline is added to the text if it does not end with one.

+The variable &$router_name$& contains the name of the router.

 
 
 
 
 
 


@@ -17225,7 +17334,8 @@ Setting this option has the effect of setting &%verify_sender%& and
 .cindex "EXPN" "with &%verify_only%&"
 .oindex "&%-bv%&"
 .cindex "router" "used only when verifying"
 .cindex "EXPN" "with &%verify_only%&"
 .oindex "&%-bv%&"
 .cindex "router" "used only when verifying"

-If this option is set, the router is used only when verifying an address or
+If this option is set, the router is used only when verifying an address,
+delivering in cutthrough mode or

 testing with the &%-bv%& option, not when actually doing a delivery, testing
 with the &%-bt%& option, or running the SMTP EXPN command. It can be further
 restricted to verifying only senders or recipients by means of
 testing with the &%-bv%& option, not when actually doing a delivery, testing
 with the &%-bt%& option, or running the SMTP EXPN command. It can be further
 restricted to verifying only senders or recipients by means of


@@ -17239,7 +17349,8 @@ user or group.
 
 .option verify_recipient routers&!? boolean true
 If this option is false, the router is skipped when verifying recipient
 
 .option verify_recipient routers&!? boolean true
 If this option is false, the router is skipped when verifying recipient

-addresses
+addresses,
+delivering in cutthrough mode

 or testing recipient verification using &%-bv%&.
 See section &<<SECTrouprecon>>& for a list of the order in which preconditions
 are evaluated.
 or testing recipient verification using &%-bv%&.
 See section &<<SECTrouprecon>>& for a list of the order in which preconditions
 are evaluated.


@@ -19547,6 +19658,8 @@ so on when debugging driver configurations. For example, if a &%headers_add%&
 option is not working properly, &%debug_print%& could be used to output the
 variables it references. A newline is added to the text if it does not end with
 one.
 option is not working properly, &%debug_print%& could be used to output the
 variables it references. A newline is added to the text if it does not end with
 one.

+The variables &$transport_name$& and &$router_name$& contain the name of the
+transport and the router that called it.

 
 
 .option delivery_date_add transports boolean false
 
 
 .option delivery_date_add transports boolean false


@@ -21540,10 +21653,10 @@ that are routed to the transport.
 .vindex "&$address_pipe$&"
 A router redirects an address directly to a pipe command (for example, from an
 alias or forward file). In this case, &$address_pipe$& contains the text of the
 .vindex "&$address_pipe$&"
 A router redirects an address directly to a pipe command (for example, from an
 alias or forward file). In this case, &$address_pipe$& contains the text of the

-pipe command, and the &%command%& option on the transport is ignored. If only
-one address is being transported (&%batch_max%& is not greater than one, or
-only one address was redirected to this pipe command), &$local_part$& contains
-the local part that was redirected.
+pipe command, and the &%command%& option on the transport is ignored unless
+&%force_command%& is set. If only one address is being transported
+(&%batch_max%& is not greater than one, or only one address was redirected to
+this pipe command), &$local_part$& contains the local part that was redirected.

 .endlist
 
 
 .endlist
 
 


@@ -21651,6 +21764,15 @@ inserted in the argument list at that point &'as a separate argument'&. This
 avoids any problems with spaces or shell metacharacters, and is of use when a
 &(pipe)& transport is handling groups of addresses in a batch.
 
 avoids any problems with spaces or shell metacharacters, and is of use when a
 &(pipe)& transport is handling groups of addresses in a batch.
 

+If &%force_command%& is enabled on the transport, Special handling takes place
+for an argument that consists of precisely the text &`$address_pipe`&.  It
+is handled similarly to &$pipe_addresses$& above.  It is expanded and each
+argument is inserted in the argument list at that point
+&'as a separate argument'&.  The &`$address_pipe`& item does not need to be
+the only item in the argument; in fact, if it were then &%force_command%&
+should behave as a no-op.  Rather, it should be used to adjust the command
+run while preserving the argument vector separation.
+

 After splitting up into arguments and expansion, the resulting command is run
 in a subprocess directly from the transport, &'not'& under a shell. The
 message that is being delivered is supplied on the standard input, and the
 After splitting up into arguments and expansion, the resulting command is run
 in a subprocess directly from the transport, &'not'& under a shell. The
 message that is being delivered is supplied on the standard input, and the


@@ -21803,6 +21925,23 @@ a bounce message is sent. If &%freeze_signal%& is set, the message will be
 frozen in Exim's queue instead.
 
 
 frozen in Exim's queue instead.
 
 

+.option force_command pipe boolean false
+.cindex "force command"
+.cindex "&(pipe)& transport", "force command"
+Normally when a router redirects an address directly to a pipe command
+the &%command%& option on the transport is ignored.  If &%force_command%&
+is set, the &%command%& option will used. This is especially
+useful for forcing a wrapper or additional argument to be added to the
+command. For example:
+.code
+command = /usr/bin/remote_exec myhost -- $address_pipe
+force_command
+.endd
+
+Note that &$address_pipe$& is handled specially in &%command%& when
+&%force_command%& is set, expanding out to the original argument vector as
+separate items, similarly to a Unix shell &`"$@"`& construct.
+

 .option ignore_status pipe boolean false
 If this option is true, the status returned by the subprocess that is set up to
 run the command is ignored, and Exim behaves as if zero had been returned.
 .option ignore_status pipe boolean false
 If this option is true, the status returned by the subprocess that is set up to
 run the command is ignored, and Exim behaves as if zero had been returned.


@@ -24041,6 +24180,12 @@ client_condition = ${if !eq{$tls_out_cipher}{}}
 .endd
 
 
 .endd
 
 

+.option client_set_id authenticators string&!! unset
+When client authentication succeeds, this condition is expanded; the
+result is used in the log lines for outbound messasges.
+Typically it will be the user name used for authentication.
+
+

 .option driver authenticators string unset
 This option must always be set. It specifies which of the available
 authenticators is to be used.
 .option driver authenticators string unset
 This option must always be set. It specifies which of the available
 authenticators is to be used.


@@ -24408,7 +24553,8 @@ to be returned. If the result of a successful expansion is an empty string,
 expansion is &"1"&, &"yes"&, or &"true"&, authentication succeeds and the
 generic &%server_set_id%& option is expanded and saved in &$authenticated_id$&.
 For any other result, a temporary error code is returned, with the expanded
 expansion is &"1"&, &"yes"&, or &"true"&, authentication succeeds and the
 generic &%server_set_id%& option is expanded and saved in &$authenticated_id$&.
 For any other result, a temporary error code is returned, with the expanded

-string as the error text.
+string as the error text, and the failed id saved in
+&$authenticated_fail_id$&.

 
 &*Warning*&: If you use a lookup in the expansion to find the user's
 password, be sure to make the authentication fail if the user is unknown.
 
 &*Warning*&: If you use a lookup in the expansion to find the user's
 password, be sure to make the authentication fail if the user is unknown.


@@ -25472,10 +25618,10 @@ aware of future feature enhancements of GnuTLS.
 
 Documentation of the strings accepted may be found in the GnuTLS manual, under
 "Priority strings".  This is online as
 
 Documentation of the strings accepted may be found in the GnuTLS manual, under
 "Priority strings".  This is online as

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

 on that site can be used to test a given string.
 
 Prior to Exim 4.80, an older API of GnuTLS was used, and Exim supported three
 on that site can be used to test a given string.
 
 Prior to Exim 4.80, an older API of GnuTLS was used, and Exim supported three


@@ -25561,7 +25707,7 @@ tls_dhparam = none
 This may also be set to a string identifying a standard prime to be used for
 DH; if it is set to &`default`& or, for OpenSSL, is unset, then the prime
 used is &`ike23`&.  There are a few standard primes available, see the
 This may also be set to a string identifying a standard prime to be used for
 DH; if it is set to &`default`& or, for OpenSSL, is unset, then the prime
 used is &`ike23`&.  There are a few standard primes available, see the

-documetnation for &%tls_dhparam%& for the complete list.
+documentation for &%tls_dhparam%& for the complete list.

 
 See the command
 .code
 
 See the command
 .code


@@ -26112,6 +26258,9 @@ before or after the data) correctly &-- they keep the message on their queues
 and try again later, but that is their problem, though it does waste some of
 your resources.
 
 and try again later, but that is their problem, though it does waste some of
 your resources.
 

+The &%acl_smtp_data%& ACL is run after both the &%acl_smtp_dkim%& and
+the &%acl_smtp_mime%& ACLs.
+

 
 .section "The SMTP DKIM ACL" "SECTDKIMACL"
 The &%acl_smtp_dkim%& ACL is available only when Exim is compiled with DKIM support
 
 .section "The SMTP DKIM ACL" "SECTDKIMACL"
 The &%acl_smtp_dkim%& ACL is available only when Exim is compiled with DKIM support


@@ -26121,13 +26270,17 @@ The ACL test specified by &%acl_smtp_dkim%& happens after a message has been
 received, and is executed for each DKIM signature found in a message.  If not
 otherwise specified, the default action is to accept.
 
 received, and is executed for each DKIM signature found in a message.  If not
 otherwise specified, the default action is to accept.
 

-For details on the operation of DKIM, see chapter &<<CHID12>>&.
+This ACL is evaluated before &%acl_smtp_mime%& and &%acl_smtp_data%&.
+
+For details on the operation of DKIM, see chapter &<<CHAPdkim>>&.

 
 
 .section "The SMTP MIME ACL" "SECID194"
 The &%acl_smtp_mime%& option is available only when Exim is compiled with the
 content-scanning extension. For details, see chapter &<<CHAPexiscan>>&.
 
 
 
 .section "The SMTP MIME ACL" "SECID194"
 The &%acl_smtp_mime%& option is available only when Exim is compiled with the
 content-scanning extension. For details, see chapter &<<CHAPexiscan>>&.
 

+This ACL is evaluated after &%acl_smtp_dkim%& but before &%acl_smtp_data%&.
+

 
 .section "The QUIT ACL" "SECTQUITACL"
 .cindex "QUIT, ACL for"
 
 .section "The QUIT ACL" "SECTQUITACL"
 .cindex "QUIT, ACL for"


@@ -26965,6 +27118,21 @@ the message is ultimately accepted. For details, see section &<<SECTremoveheadac
 .cindex "&%set%& ACL modifier"
 This modifier puts a value into one of the ACL variables (see section
 &<<SECTaclvariables>>&).
 .cindex "&%set%& ACL modifier"
 This modifier puts a value into one of the ACL variables (see section
 &<<SECTaclvariables>>&).

+
+
+.vitem &*udpsend*&&~=&~<&'parameters'&>
+This modifier sends a UDP packet, for purposes such as statistics
+collection or behaviour monitoring. The parameters are expanded, and
+the result of the expansion must be a colon-separated list consisting
+of a destination server, port number, and the packet contents. The
+server can be specified as a host name or IPv4 or IPv6 address. The
+separator can be changed with the usual angle bracket syntax. For
+example, you might want to collect information on which hosts connect
+when:
+.code
+udpsend = <; 2001:dB8::dead:beef ; 1234 ;\
+             $tod_zulu $sender_host_address
+.endd

 .endlist
 
 
 .endlist
 
 


@@ -27030,11 +27198,12 @@ is what is wanted for subsequent tests.
 .new
 .vitem &*control&~=&~cutthrough_delivery*&
 .cindex "&ACL;" "cutthrough routing"
 .new
 .vitem &*control&~=&~cutthrough_delivery*&
 .cindex "&ACL;" "cutthrough routing"

+.cindex "cutthrough" "requesting"

 This option requests delivery be attempted while the item is being received.
 It is usable in the RCPT ACL and valid only for single-recipient mails forwarded
 from one SMTP connection to another.  If a recipient-verify callout connection is
 requested in the same ACL it is held open and used for the data, otherwise one is made
 This option requests delivery be attempted while the item is being received.
 It is usable in the RCPT ACL and valid only for single-recipient mails forwarded
 from one SMTP connection to another.  If a recipient-verify callout connection is
 requested in the same ACL it is held open and used for the data, otherwise one is made

-after the ACL completes.
+after the ACL completes.  Note that routers are used in verify mode.

 
 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.


@@ -27073,7 +27242,7 @@ contexts):
 .cindex "disable DKIM verify"
 .cindex "DKIM" "disable verify"
 This control turns off DKIM verification processing entirely.  For details on
 .cindex "disable DKIM verify"
 .cindex "DKIM" "disable verify"
 This control turns off DKIM verification processing entirely.  For details on

-the operation and configuration of DKIM, see chapter &<<CHID12>>&.
+the operation and configuration of DKIM, see chapter &<<CHAPdkim>>&.

 .wen
 
 
 .wen
 
 


@@ -27301,7 +27470,9 @@ receiving a message). The message must ultimately be accepted for
 any ACL verb, including &%deny%& (though this is potentially useful only in a
 RCPT ACL).
 
 any ACL verb, including &%deny%& (though this is potentially useful only in a
 RCPT ACL).
 

-If the data for the &%add_header%& modifier contains one or more newlines that
+Leading and trailing newlines are removed from
+the data for the &%add_header%& modifier; if it then
+contains one or more newlines that

 are not followed by a space or a tab, it is assumed to contain multiple header
 lines. Each one is checked for valid syntax; &`X-ACL-Warn:`& is added to the
 front of any line that is not a valid header line.
 are not followed by a space or a tab, it is assumed to contain multiple header
 lines. Each one is checked for valid syntax; &`X-ACL-Warn:`& is added to the
 front of any line that is not a valid header line.


@@ -27319,7 +27490,9 @@ message is rejected after DATA or by the non-SMTP ACL, all added header lines
 are included in the entry that is written to the reject log.
 
 .cindex "header lines" "added; visibility of"
 are included in the entry that is written to the reject log.
 
 .cindex "header lines" "added; visibility of"

-Header lines are not visible in string expansions until they are added to the
+Header lines are not visible in string expansions
+of message headers
+until they are added to the

 message. It follows that header lines defined in the MAIL, RCPT, and predata
 ACLs are not visible until the DATA ACL and MIME ACLs are run. Similarly,
 header lines that are added by the DATA or MIME ACLs are not visible in those
 message. It follows that header lines defined in the MAIL, RCPT, and predata
 ACLs are not visible until the DATA ACL and MIME ACLs are run. Similarly,
 header lines that are added by the DATA or MIME ACLs are not visible in those


@@ -27328,6 +27501,8 @@ passing data between (for example) the MAIL and RCPT ACLs. If you want to do
 this, you can use ACL variables, as described in section
 &<<SECTaclvariables>>&.
 
 this, you can use ACL variables, as described in section
 &<<SECTaclvariables>>&.
 

+The list of headers yet to be added is given by the &%$headers_added%& variable.
+

 The &%add_header%& modifier acts immediately as it is encountered during the
 processing of an ACL. Notice the difference between these two cases:
 .display
 The &%add_header%& modifier acts immediately as it is encountered during the
 processing of an ACL. Notice the difference between these two cases:
 .display


@@ -27480,8 +27655,10 @@ condition false. This means that further processing of the &%warn%& verb
 ceases, but processing of the ACL continues.
 
 If the argument is a named ACL, up to nine space-separated optional values
 ceases, but processing of the ACL continues.
 
 If the argument is a named ACL, up to nine space-separated optional values

-can be appended; they appear in $acl_arg1 to $acl_arg9, and $acl_narg is set
-to the count of values.  The name and values are expanded separately.
+can be appended; they appear within the called ACL in $acl_arg1 to $acl_arg9,
+and $acl_narg is set to the count of values.
+Previous values of these variables are restored after the call returns.
+The name and values are expanded separately.

 
 If the nested &%acl%& returns &"drop"& and the outer condition denies access,
 the connection is dropped. If it returns &"discard"&, the verb must be
 
 If the nested &%acl%& returns &"drop"& and the outer condition denies access,
 the connection is dropped. If it returns &"discard"&, the verb must be


@@ -28726,6 +28903,9 @@ following SMTP commands are sent:
 LHLO is used instead of HELO if the transport's &%protocol%& option is
 set to &"lmtp"&.
 
 LHLO is used instead of HELO if the transport's &%protocol%& option is
 set to &"lmtp"&.
 

+The callout may use EHLO, AUTH and/or STARTTLS given appropriate option
+settings.
+

 A recipient callout check is similar. By default, it also uses an empty address
 for the sender. This default is chosen because most hosts do not make use of
 the sender address when verifying a recipient. Using the same address means
 A recipient callout check is similar. By default, it also uses an empty address
 for the sender. This default is chosen because most hosts do not make use of
 the sender address when verifying a recipient. Using the same address means


@@ -33496,6 +33676,7 @@ timestamp. The flags are:
 &`<=`&     message arrival
 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery
 &`<=`&     message arrival
 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery

+&`>>`&     cutthrough message delivery

 &`*>`&     delivery suppressed by &%-N%&
 &`**`&     delivery failed; address bounced
 &`==`&     delivery deferred; temporary problem
 &`*>`&     delivery suppressed by &%-N%&
 &`**`&     delivery failed; address bounced
 &`==`&     delivery deferred; temporary problem


@@ -33595,6 +33776,11 @@ intermediate address(es) exist between the original and the final address, the
 last of these is given in parentheses after the final address. The R and T
 fields record the router and transport that were used to process the address.
 
 last of these is given in parentheses after the final address. The R and T
 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%&
+option, this is logged too, separated by a colon from the authenticator name.
+

 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
 .display
 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
 .display


@@ -33610,6 +33796,12 @@ flagged with &`->`& instead of &`=>`&. When two or more messages are delivered
 down a single SMTP connection, an asterisk follows the IP address in the log
 lines for the second and subsequent messages.
 
 down a single SMTP connection, an asterisk follows the IP address in the log
 lines for the second and subsequent messages.
 

+.cindex "delivery" "cutthrough; logging"
+.cindex "cutthrough" "logging"
+When delivery is done in cutthrough mode it is flagged with &`>>`& and the log
+line precedes the reception line, since cutthrough waits for a possible
+rejection from the destination in case it can reject the sourced item.
+

 The generation of a reply message by a filter file gets logged as a
 &"delivery"& to the addressee, preceded by &">"&.
 
 The generation of a reply message by a filter file gets logged as a
 &"delivery"& to the addressee, preceded by &">"&.
 


@@ -33702,7 +33894,7 @@ at the end of its processing.
 A summary of the field identifiers that are used in log lines is shown in
 the following table:
 .display
 A summary of the field identifiers that are used in log lines is shown in
 the following table:
 .display

-&`A   `&        authenticator name (and optional id)
+&`A   `&        authenticator name (and optional id and sender)

 &`C   `&        SMTP confirmation on delivery
 &`    `&        command list for &"no mail in SMTP session"&
 &`CV  `&        certificate verification status
 &`C   `&        SMTP confirmation on delivery
 &`    `&        command list for &"no mail in SMTP session"&
 &`CV  `&        certificate verification status


@@ -33786,6 +33978,7 @@ log_selector = +arguments -retry_defer
 The list of optional log items is in the following table, with the default
 selection marked by asterisks:
 .display
 The list of optional log items is in the following table, with the default
 selection marked by asterisks:
 .display

+&` 8bitmime                   `&  received 8BITMIME status

 &`*acl_warn_skipped           `&  skipped &%warn%& statement in ACL
 &` address_rewrite            `&  address rewriting
 &` all_parents                `&  all parents in => lines
 &`*acl_warn_skipped           `&  skipped &%warn%& statement in ACL
 &` address_rewrite            `&  address rewriting
 &` all_parents                `&  all parents in => lines


@@ -33818,6 +34011,7 @@ selection marked by asterisks:
 &`*smtp_confirmation          `&  SMTP confirmation on => lines
 &` smtp_connection            `&  SMTP connections
 &` smtp_incomplete_transaction`&  incomplete SMTP transactions
 &`*smtp_confirmation          `&  SMTP confirmation on => lines
 &` smtp_connection            `&  SMTP connections
 &` smtp_incomplete_transaction`&  incomplete SMTP transactions

+&` smtp_mailauth              `&  AUTH argument to MAIL commands

 &` smtp_no_mail               `&  session with no MAIL commands
 &` smtp_protocol_error        `&  SMTP protocol errors
 &` smtp_syntax_error          `&  SMTP syntax errors
 &` smtp_no_mail               `&  session with no MAIL commands
 &` smtp_protocol_error        `&  SMTP protocol errors
 &` smtp_syntax_error          `&  SMTP syntax errors


@@ -33833,6 +34027,14 @@ selection marked by asterisks:
 More details on each of these items follows:
 
 .ilist
 More details on each of these items follows:
 
 .ilist

+.cindex "8BITMIME"
+.cindex "log" "8BITMIME"
+&%8bitmime%&: This causes Exim to log any 8BITMIME status of received messages,
+which may help in tracking down interoperability issues with ancient MTAs
+that are not 8bit clean.  This is added to the &"<="& line, tagged with
+&`M8S=`& and a value of &`0`&, &`7`& or &`8`&, corresponding to "not given",
+&`7BIT`& and &`8BITMIME`& respectively.
+.next

 .cindex "&%warn%& ACL verb" "log when skipping"
 &%acl_warn_skipped%&: When an ACL &%warn%& statement is skipped because one of
 its conditions cannot be evaluated, a log line to this effect is written if
 .cindex "&%warn%& ACL verb" "log when skipping"
 &%acl_warn_skipped%&: When an ACL &%warn%& statement is skipped because one of
 its conditions cannot be evaluated, a log line to this effect is written if


@@ -34078,6 +34280,11 @@ the last 20 are listed, preceded by &"..."&. However, with the default
 setting of 10 for &%smtp_accep_max_nonmail%&, the connection will in any case
 have been aborted before 20 non-mail commands are processed.
 .next
 setting of 10 for &%smtp_accep_max_nonmail%&, the connection will in any case
 have been aborted before 20 non-mail commands are processed.
 .next

+&%smtp_mailauth%&: A third subfield with the authenticated sender,
+colon-separated, is appended to the A= item for a message arrival or delivery
+log line, if an AUTH argument to the SMTP MAIL command (see &<<SECTauthparamail>>&)
+was accepted or used.
+.next

 .cindex "log" "SMTP protocol error"
 .cindex "SMTP" "logging protocol error"
 &%smtp_protocol_error%&: A log line is written for every SMTP protocol error
 .cindex "log" "SMTP protocol error"
 .cindex "SMTP" "logging protocol error"
 &%smtp_protocol_error%&: A log line is written for every SMTP protocol error


@@ -34249,14 +34456,14 @@ options are available:
 
 .vlist
 .vitem &*-f*&&~<&'regex'&>
 
 .vlist
 .vitem &*-f*&&~<&'regex'&>

-Match the sender address. The field that is tested is enclosed in angle
-brackets, so you can test for bounce messages with
+Match the sender address using a case-insensitive search. The field that is
+tested is enclosed in angle brackets, so you can test for bounce messages with

 .code
 exiqgrep -f '^<>$'
 .endd
 .vitem &*-r*&&~<&'regex'&>
 .code
 exiqgrep -f '^<>$'
 .endd
 .vitem &*-r*&&~<&'regex'&>

-Match a recipient address. The field that is tested is not enclosed in angle
-brackets.
+Match a recipient address using a case-insensitve search. The field that is
+tested is not enclosed in angle brackets.

 
 .vitem &*-s*&&~<&'regex'&>
 Match against the size field.
 
 .vitem &*-s*&&~<&'regex'&>
 Match against the size field.


@@ -35480,6 +35687,50 @@ are given in chapter &<<CHAPappendfile>>&.
 
 
 
 
 
 

+.section "Running local commands" "SECTsecconslocalcmds"
+There are a number of ways in which an administrator can configure Exim to run
+commands based upon received, untrustworthy, data. Further, in some
+configurations a user who can control a &_.forward_& file can also arrange to
+run commands. Configuration to check includes, but is not limited to:
+
+.ilist
+Use of &%use_shell%& in the pipe transport: various forms of shell command
+injection may be possible with this option present. It is dangerous and should
+be used only with considerable caution. Consider constraints which whitelist
+allowed characters in a variable which is to be used in a pipe transport that
+has &%use_shell%& enabled.
+.next
+A number of options such as &%forbid_filter_run%&, &%forbid_filter_perl%&,
+&%forbid_filter_dlfunc%& and so forth which restrict facilities available to
+&_.forward_& files in a redirect router. If Exim is running on a central mail
+hub to which ordinary users do not have shell access, but home directories are
+NFS mounted (for instance) then administrators should review the list of these
+forbid options available, and should bear in mind that the options that may
+need forbidding can change as new features are added between releases.
+.next
+The &%${run...}%& expansion item does not use a shell by default, but
+administrators can configure use of &_/bin/sh_& as part of the command.
+Such invocations should be viewed with prejudicial suspicion.
+.next
+Administrators who use embedded Perl are advised to explore how Perl's
+taint checking might apply to their usage.
+.next
+Use of &%${expand...}%& is somewhat analagous to shell's eval builtin and
+administrators are well advised to view its use with suspicion, in case (for
+instance) it allows a local-part to contain embedded Exim directives.
+.next
+Use of &%${match_local_part...}%& and friends becomes more dangerous if
+Exim was built with EXPAND_LISTMATCH_RHS defined: the second string in
+each can reference arbitrary lists and files, rather than just being a list
+of opaque strings.
+The EXPAND_LISTMATCH_RHS option was added and set false by default because of
+real-world security vulnerabilities caused by its use with untrustworthy data
+injected in, for SQL injection attacks.
+Consider the use of the &%inlisti%& expansion condition instead.
+.endlist
+
+
+

 .section "IPv4 source routing" "SECID272"
 .cindex "source routing" "in IP packets"
 .cindex "IP source routing"
 .section "IPv4 source routing" "SECID272"
 .cindex "source routing" "in IP packets"
 .cindex "IP source routing"


@@ -35937,7 +36188,7 @@ unqualified domain &'foundation'&.
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 

-.chapter "Support for DKIM (DomainKeys Identified Mail)" "CHID12" &&&
+.chapter "Support for DKIM (DomainKeys Identified Mail)" "CHAPdkim" &&&

          "DKIM Support"
 .cindex "DKIM"
 
          "DKIM Support"
 .cindex "DKIM"
 


@@ -36234,6 +36485,12 @@ Add to &_src/config.h.defaults_& the line:
 Edit &_src/drtables.c_&, adding conditional code to pull in the private header
 and create a table entry as is done for all the other drivers and lookup types.
 .next
 Edit &_src/drtables.c_&, adding conditional code to pull in the private header
 and create a table entry as is done for all the other drivers and lookup types.
 .next

+Edit &_scripts/lookups-Makefile_& if this is a new lookup; there is a for-loop
+near the bottom, ranging the &`name_mod`& variable over a list of all lookups.
+Add your &`NEWDRIVER`& to that list.
+As long as the dynamic module would be named &_newdriver.so_&, you can use the
+simple form that most lookups have.
+.next

 Edit &_Makefile_& in the appropriate sub-directory (&_src/routers_&,
 &_src/transports_&, &_src/auths_&, or &_src/lookups_&); add a line for the new
 driver or lookup type and add it to the definition of OBJ.
 Edit &_Makefile_& in the appropriate sub-directory (&_src/routers_&,
 &_src/transports_&, &_src/auths_&, or &_src/lookups_&); add a line for the new
 driver or lookup type and add it to the definition of OBJ.