Reword BSMTP ACL documentation

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index b640daec638fb5f928523ca79ce4185298ec7da5..47402cb40ba940b015e064285ce86362b8c3858b 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -1,4 +1,4 @@
-. $Cambridge: exim/doc/doc-docbook/spec.xfpt,v 1.68 2009/11/16 19:10:45 nm4 Exp $
+. $Cambridge: exim/doc/doc-docbook/spec.xfpt,v 1.88 2010/06/14 18:51:09 pdp Exp $

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


@@ -47,8 +47,8 @@
 . the <bookinfo> element must also be updated for each new edition.
 . /////////////////////////////////////////////////////////////////////////////
 
 . the <bookinfo> element must also be updated for each new edition.
 . /////////////////////////////////////////////////////////////////////////////
 

-.set previousversion "4.69"
-.set version "4.71"
+.set previousversion "4.72"
+.set version "4.73"

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


@@ -172,12 +172,12 @@
 <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>5 November 2009</date>
+<date>29 May 2010</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>4.71</revnumber>
-  <date>5 November 2009</date>
+  <revnumber>4.73</revnumber>
+  <date>19 Nov 2010</date>

   <authorinitials>EM</authorinitials>
 </revision></revhistory>
 <copyright><year>2009</year><holder>University of Cambridge</holder></copyright>
   <authorinitials>EM</authorinitials>
 </revision></revhistory>
 <copyright><year>2009</year><holder>University of Cambridge</holder></copyright>


@@ -726,14 +726,12 @@ the Exim documentation, &"spool"& is always used in the first sense.
 A number of pieces of external code are included in the Exim distribution.
 
 .ilist
 A number of pieces of external code are included in the Exim distribution.
 
 .ilist

-.new

 Regular expressions are supported in the main Exim program and in the
 Exim monitor using the freely-distributable PCRE library, copyright
 &copy; University of Cambridge. The source to PCRE is no longer shipped with
 Exim, so you will need to use the version of PCRE shipped with your system,
 or obtain and install the full version of the library from
 &url(ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre).
 Regular expressions are supported in the main Exim program and in the
 Exim monitor using the freely-distributable PCRE library, copyright
 &copy; University of Cambridge. The source to PCRE is no longer shipped with
 Exim, so you will need to use the version of PCRE shipped with your system,
 or obtain and install the full version of the library from
 &url(ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre).

-.wen

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


@@ -1546,7 +1544,6 @@ If a host is unreachable for a period of time, a number of messages may be
 waiting for it by the time it recovers, and sending them in a single SMTP
 connection is clearly beneficial. Whenever a delivery to a remote host is
 deferred,
 waiting for it by the time it recovers, and sending them in a single SMTP
 connection is clearly beneficial. Whenever a delivery to a remote host is
 deferred,

-

 .cindex "hints database"
 Exim makes a note in its hints database, and whenever a successful
 SMTP delivery has happened, it looks to see if any other messages are waiting
 .cindex "hints database"
 Exim makes a note in its hints database, and whenever a successful
 SMTP delivery has happened, it looks to see if any other messages are waiting


@@ -1896,8 +1893,11 @@ given in chapter &<<CHAPTLS>>&.
 
 
 .section "Use of tcpwrappers" "SECID27"
 
 
 .section "Use of tcpwrappers" "SECID27"

+.new

 .cindex "tcpwrappers, building Exim to support"
 .cindex "USE_TCP_WRAPPERS"
 .cindex "tcpwrappers, building Exim to support"
 .cindex "USE_TCP_WRAPPERS"

+.cindex "TCP_WRAPPERS_DAEMON_NAME"
+.cindex "tcp_wrappers_daemon_name"

 Exim can be linked with the &'tcpwrappers'& library in order to check incoming
 SMTP calls using the &'tcpwrappers'& control files. This may be a convenient
 alternative to Exim's own checking facilities for installations that are
 Exim can be linked with the &'tcpwrappers'& library in order to check incoming
 SMTP calls using the &'tcpwrappers'& control files. This may be a convenient
 alternative to Exim's own checking facilities for installations that are


@@ -1912,16 +1912,19 @@ USE_TCP_WRAPPERS=yes
 CFLAGS=-O -I/usr/local/include
 EXTRALIBS_EXIM=-L/usr/local/lib -lwrap
 .endd
 CFLAGS=-O -I/usr/local/include
 EXTRALIBS_EXIM=-L/usr/local/lib -lwrap
 .endd

-in &_Local/Makefile_&. The name to use in the &'tcpwrappers'& control files is
-&"exim"&. For example, the line
+in &_Local/Makefile_&. The daemon name to use in the &'tcpwrappers'& control
+files is &"exim"&. For example, the line

 .code
 exim : LOCAL  192.168.1.  .friendly.domain.example
 .endd
 in your &_/etc/hosts.allow_& file allows connections from the local host, from
 the subnet 192.168.1.0/24, and from all hosts in &'friendly.domain.example'&.
 .code
 exim : LOCAL  192.168.1.  .friendly.domain.example
 .endd
 in your &_/etc/hosts.allow_& file allows connections from the local host, from
 the subnet 192.168.1.0/24, and from all hosts in &'friendly.domain.example'&.

-All other connections are denied. Consult the &'tcpwrappers'& documentation for
+All other connections are denied. The daemon name used by &'tcpwrappers'&
+can be changed at build time by setting TCP_WRAPPERS_DAEMON_NAME in
+in &_Local/Makefile_&, or by setting tcp_wrappers_daemon_name in the
+configure file. Consult the &'tcpwrappers'& documentation for

 further details.
 further details.

-
+.wen

 
 
 .section "Including support for IPv6" "SECID28"
 
 
 .section "Including support for IPv6" "SECID28"


@@ -2221,14 +2224,12 @@ configuration. (If a default alias file is created, its name &'is'& modified.)
 For backwards compatibility, ROOT is used if DESTDIR is not set,
 but this usage is deprecated.
 
 For backwards compatibility, ROOT is used if DESTDIR is not set,
 but this usage is deprecated.
 

-.new

 .cindex "installing Exim" "what is not installed"
 Running &'make install'& does not copy the Exim 4 conversion script
 &'convert4r4'&. You will probably run this only once if you are
 upgrading from Exim 3. None of the documentation files in the &_doc_&
 directory are copied, except for the info files when you have set
 INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.
 .cindex "installing Exim" "what is not installed"
 Running &'make install'& does not copy the Exim 4 conversion script
 &'convert4r4'&. You will probably run this only once if you are
 upgrading from Exim 3. None of the documentation files in the &_doc_&
 directory are copied, except for the info files when you have set
 INFO_DIRECTORY, as described in section &<<SECTinsinfdoc>>& below.

-.wen

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


@@ -2608,6 +2609,13 @@ This option causes Exim to output a few sentences stating what it is.
 The same output is generated if the Exim binary is called with no options and
 no arguments.
 
 The same output is generated if the Exim binary is called with no options and
 no arguments.
 

+.new
+.vitem &%--version%&
+.oindex "&%--version%&"
+This option is an alias for &%-bV%& and causes version information to be
+displayed.
+.wen
+

 .vitem &%-B%&<&'type'&>
 .oindex "&%-B%&"
 .cindex "8-bit characters"
 .vitem &%-B%&<&'type'&>
 .oindex "&%-B%&"
 .cindex "8-bit characters"


@@ -2991,13 +2999,11 @@ using one of the words &%router_list%&, &%transport_list%&, or
 settings can be obtained by using &%routers%&, &%transports%&, or
 &%authenticators%&.
 
 settings can be obtained by using &%routers%&, &%transports%&, or
 &%authenticators%&.
 

-.new

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

-.wen

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


@@ -3175,6 +3181,28 @@ above concerning senders and qualification do not apply. In this situation,
 Exim behaves in exactly the same way as it does when receiving a message via
 the listening daemon.
 
 Exim behaves in exactly the same way as it does when receiving a message via
 the listening daemon.
 

+.new
+.vitem &%-bmalware%&&~<&'filename'&>
+.oindex "&%-bmalware%&"
+.cindex "testing", "malware"
+.cindex "malware scan test"
+This debugging option causes Exim to scan the given file,
+using the malware scanning framework.  The option of &%av_scanner%& influences
+this option, so if &%av_scanner%&'s value is dependent upon an expansion then
+the expansion should have defaults which apply to this invocation.  ACLs are
+not invoked, so if &%av_scanner%& references an ACL variable then that variable
+will never be populated and &%-bmalware%& will fail.
+
+Exim will have changed working directory before resolving the filename, so
+using fully qualified pathnames is advisable.  Exim will be running as the Exim
+user when it tries to open the file, rather than as the invoking user.
+This option requires admin privileges.
+
+The &%-bmalware%& option will not be extended to be more generally useful,
+there are better tools for file-scanning.  This option exists to help
+administrators verify their Exim and AV scanner configuration.
+.wen
+

 .vitem &%-bt%&
 .oindex "&%-bt%&"
 .cindex "testing" "addresses"
 .vitem &%-bt%&
 .oindex "&%-bt%&"
 .cindex "testing" "addresses"


@@ -3226,7 +3254,7 @@ doing such tests.
 .cindex "version number of Exim"
 This option causes Exim to write the current version number, compilation
 number, and compilation date of the &'exim'& binary to the standard output.
 .cindex "version number of Exim"
 This option causes Exim to write the current version number, compilation
 number, and compilation date of the &'exim'& binary to the standard output.

-It also lists the DBM library this is being used, the optional modules (such as
+It also lists the DBM library that is being used, the optional modules (such as

 specific lookup types), the drivers that are included in the binary, and the
 name of the run time configuration file that is in use.
 
 specific lookup types), the drivers that are included in the binary, and the
 name of the run time configuration file that is in use.
 


@@ -3295,6 +3323,7 @@ This option acts like &%-bv%&, but verifies the address as a sender rather
 than a recipient address. This affects any rewriting and qualification that
 might happen.
 
 than a recipient address. This affects any rewriting and qualification that
 might happen.
 

+.new

 .vitem &%-C%&&~<&'filelist'&>
 .oindex "&%-C%&"
 .cindex "configuration file" "alternate"
 .vitem &%-C%&&~<&'filelist'&>
 .oindex "&%-C%&"
 .cindex "configuration file" "alternate"


@@ -3307,25 +3336,23 @@ name, but it can be a colon-separated list of names. In this case, the first
 file that exists is used. Failure to open an existing file stops Exim from
 proceeding any further along the list, and an error is generated.
 
 file that exists is used. Failure to open an existing file stops Exim from
 proceeding any further along the list, and an error is generated.
 

-When this option is used by a caller other than root or the Exim user, and the
-list is different from the compiled-in list, Exim gives up its root privilege
-immediately, and runs with the real and effective uid and gid set to those of
-the caller. However, if ALT_CONFIG_ROOT_ONLY is defined in
-&_Local/Makefile_&, root privilege is retained for &%-C%& only if the caller of
-Exim is root.
-
-That is, the Exim user is no longer privileged in this regard. This build-time
-option is not set by default in the Exim source distribution tarbundle.
-However, if you are using a &"packaged"& version of Exim (source or binary),
-the packagers might have enabled it.
-
-Setting ALT_CONFIG_ROOT_ONLY locks out the possibility of testing a
-configuration using &%-C%& right through message reception and delivery, even
-if the caller is root. The reception works, but by that time, Exim is running
-as the Exim user, so when it re-executes to regain privilege for the delivery,
-the use of &%-C%& causes privilege to be lost. However, root can test reception
-and delivery using two separate commands (one to put a message on the queue,
-using &%-odq%&, and another to do the delivery, using &%-M%&).
+When this option is used by a caller other than root, and the list is different
+from the compiled-in list, Exim gives up its root privilege immediately, and
+runs with the real and effective uid and gid set to those of the caller.
+However, if a TRUSTED_CONFIG_LIST file is defined in &_Local/Makefile_&, that
+file contains a list of full pathnames, one per line, for configuration files
+which are trusted. Root privilege is retained for any configuration file so
+listed, as long as the caller is the Exim user (or the user specified in the
+CONFIGURE_OWNER option, if any), and as long as the configuration file is
+not writeable by inappropriate users or groups.
+
+Leaving TRUSTED_CONFIG_LIST unset precludes the possibility of testing a
+configuration using &%-C%& right through message reception and delivery,
+even if the caller is root. The reception works, but by that time, Exim is
+running as the Exim user, so when it re-executes to regain privilege for the
+delivery, the use of &%-C%& causes privilege to be lost. However, root can
+test reception and delivery using two separate commands (one to put a message
+on the queue, using &%-odq%&, and another to do the delivery, using &%-M%&).

 
 If ALT_CONFIG_PREFIX is defined &_in Local/Makefile_&, it specifies a
 prefix string with which any file named in a &%-C%& command line option
 
 If ALT_CONFIG_PREFIX is defined &_in Local/Makefile_&, it specifies a
 prefix string with which any file named in a &%-C%& command line option


@@ -3345,7 +3372,9 @@ syntactically correct, but cannot be used for test deliveries, unless the
 caller is privileged, or unless it is an exotic configuration that does not
 require privilege. No check is made on the owner or group of the files
 specified by this option.
 caller is privileged, or unless it is an exotic configuration that does not
 require privilege. No check is made on the owner or group of the files
 specified by this option.

+.wen

 
 

+.new

 .vitem &%-D%&<&'macro'&>=<&'value'&>
 .oindex "&%-D%&"
 .cindex "macro" "setting on command line"
 .vitem &%-D%&<&'macro'&>=<&'value'&>
 .oindex "&%-D%&"
 .cindex "macro" "setting on command line"


@@ -3355,6 +3384,14 @@ unprivileged caller, it causes Exim to give up its root privilege.
 If DISABLE_D_OPTION is defined in &_Local/Makefile_&, the use of &%-D%& is
 completely disabled, and its use causes an immediate error exit.
 
 If DISABLE_D_OPTION is defined in &_Local/Makefile_&, the use of &%-D%& is
 completely disabled, and its use causes an immediate error exit.
 

+If WHITELIST_D_MACROS is defined in &_Local/Makefile_& then it should be a
+colon-separated list of macros which are considered safe and, if &%-D%& only
+supplies macros from this list, and the values are acceptable, then Exim will
+not give up root privilege if the caller is root, the Exim run-time user, or
+the CONFIGURE_OWNER, if set.  This is a transition mechanism and is expected
+to be removed in the future.  Acceptable values for the macros satisfy the
+regexp: &`^[A-Za-z0-9_/.-]*$`&
+

 The entire option (including equals sign if present) must all be within one
 command line item. &%-D%& can be used to set the value of a macro to the empty
 string, in which case the equals sign is optional. These two commands are
 The entire option (including equals sign if present) must all be within one
 command line item. &%-D%& can be used to set the value of a macro to the empty
 string, in which case the equals sign is optional. These two commands are


@@ -3370,6 +3407,7 @@ example:
 exim '-D ABC = something' ...
 .endd
 &%-D%& may be repeated up to 10 times on a command line.
 exim '-D ABC = something' ...
 .endd
 &%-D%& may be repeated up to 10 times on a command line.

+.wen

 
 .vitem &%-d%&<&'debug&~options'&>
 .oindex "&%-d%&"
 
 .vitem &%-d%&<&'debug&~options'&>
 .oindex "&%-d%&"


@@ -3751,7 +3789,7 @@ written to the standard output. This option can be used only by an admin user.
 .vitem &%-Mvc%&&~<&'message&~id'&>
 .oindex "&%-Mvc%&"
 .cindex "message" "listing in RFC 2822 format"
 .vitem &%-Mvc%&&~<&'message&~id'&>
 .oindex "&%-Mvc%&"
 .cindex "message" "listing in RFC 2822 format"

-.cindex "listing" "message in RFC 2922 format"
+.cindex "listing" "message in RFC 2822 format"

 This option causes a copy of the complete message (header lines plus body) to
 be written to the standard output in RFC 2822 format. This option can be used
 only by an admin user.
 This option causes a copy of the complete message (header lines plus body) to
 be written to the standard output in RFC 2822 format. This option can be used
 only by an admin user.


@@ -4470,6 +4508,7 @@ most configurations, this specifies a single file. However, it is permitted to
 give a colon-separated list of file names, in which case Exim uses the first
 existing file in the list.
 
 give a colon-separated list of file names, in which case Exim uses the first
 existing file in the list.
 

+.new

 .cindex "EXIM_USER"
 .cindex "EXIM_GROUP"
 .cindex "CONFIGURE_OWNER"
 .cindex "EXIM_USER"
 .cindex "EXIM_GROUP"
 .cindex "CONFIGURE_OWNER"


@@ -4477,17 +4516,21 @@ existing file in the list.
 .cindex "configuration file" "ownership"
 .cindex "ownership" "configuration file"
 The run time configuration file must be owned by root or by the user that is
 .cindex "configuration file" "ownership"
 .cindex "ownership" "configuration file"
 The run time configuration file must be owned by root or by the user that is

-specified at compile time by the EXIM_USER option, or by the user that is

 specified at compile time by the CONFIGURE_OWNER option (if set). The
 specified at compile time by the CONFIGURE_OWNER option (if set). The

-configuration file must not be world-writeable or group-writeable, unless its
-group is the one specified at compile time by the EXIM_GROUP option or by the
+configuration file must not be world-writeable, or group-writeable unless its
+group is the root group or the one specified at compile time by the

 CONFIGURE_GROUP option.
 
 &*Warning*&: In a conventional configuration, where the Exim binary is setuid
 to root, anybody who is able to edit the run time configuration file has an
 CONFIGURE_GROUP option.
 
 &*Warning*&: In a conventional configuration, where the Exim binary is setuid
 to root, anybody who is able to edit the run time configuration file has an

-easy way to run commands as root. If you make your mail administrators members
-of the Exim group, but do not trust them with root, make sure that the run time
-configuration is not group writeable.
+easy way to run commands as root. If you specify a user or group in the
+CONFIGURE_OWNER or CONFIGURE_GROUP options, then that user and/or any users
+who are members of that group will trivially be able to obtain root privileges.
+
+Up to Exim version 4.72, the run time configuration file was also permitted to
+be writeable by the Exim user and/or group. That has been changed in Exim 4.73
+since it offered a simple privilege escalation for any attacker who managed to
+compromise the Exim user account.

 
 A default configuration file, which will work correctly in simple situations,
 is provided in the file &_src/configure.default_&. If CONFIGURE_FILE
 
 A default configuration file, which will work correctly in simple situations,
 is provided in the file &_src/configure.default_&. If CONFIGURE_FILE


@@ -4496,28 +4539,31 @@ configuration to a new file of that name if it did not previously exist. If
 CONFIGURE_FILE is a list, no default is automatically installed. Chapter
 &<<CHAPdefconfil>>& is a &"walk-through"& discussion of the default
 configuration.
 CONFIGURE_FILE is a list, no default is automatically installed. Chapter
 &<<CHAPdefconfil>>& is a &"walk-through"& discussion of the default
 configuration.

-
+.wen

 
 
 .section "Using a different configuration file" "SECID40"
 .cindex "configuration file" "alternate"
 A one-off alternate configuration can be specified by the &%-C%& command line
 option, which may specify a single file or a list of files. However, when
 
 
 .section "Using a different configuration file" "SECID40"
 .cindex "configuration file" "alternate"
 A one-off alternate configuration can be specified by the &%-C%& command line
 option, which may specify a single file or a list of files. However, when

-&%-C%& is used, Exim gives up its root privilege, unless called by root or the
-Exim user (or unless the argument for &%-C%& is identical to the built-in value
-from CONFIGURE_FILE). &%-C%& is useful mainly for checking the syntax of
-configuration files before installing them. No owner or group checks are done
-on a configuration file specified by &%-C%&.
-
-The privileged use of &%-C%& by the Exim user can be locked out by setting
-ALT_CONFIG_ROOT_ONLY in &_Local/Makefile_& when building Exim. However,
-if you do this, you also lock out the possibility of testing a
-configuration using &%-C%& right through message reception and delivery, even
-if the caller is root. The reception works, but by that time, Exim is running
-as the Exim user, so when it re-execs to regain privilege for the delivery, the
-use of &%-C%& causes privilege to be lost. However, root can test reception and
-delivery using two separate commands (one to put a message on the queue, using
-&%-odq%&, and another to do the delivery, using &%-M%&).
+&%-C%& is used, Exim gives up its root privilege, unless called by root (or
+unless the argument for &%-C%& is identical to the built-in value from
+CONFIGURE_FILE), or is listed in the TRUSTED_CONFIG_LIST file and the caller
+is the Exim user or the user specified in the CONFIGURE_OWNER setting. &%-C%&
+is useful mainly for checking the syntax of configuration files before
+installing them. No owner or group checks are done on a configuration file
+specified by &%-C%&, if root privilege has been dropped.
+
+Even the Exim user is not trusted to specify an arbitrary configuration file
+with the &%-C%& option to be used with root privileges, unless that file is
+listed in the TRUSTED_CONFIG_LIST file. This locks out the possibility of
+testing a configuration using &%-C%& right through message reception and
+delivery, even if the caller is root. The reception works, but by that time,
+Exim is running as the Exim user, so when it re-execs to regain privilege for
+the delivery, the use of &%-C%& causes privilege to be lost. However, root
+can test reception and delivery using two separate commands (one to put a
+message on the queue, using &%-odq%&, and another to do the delivery, using
+&%-M%&).

 
 If ALT_CONFIG_PREFIX is defined &_in Local/Makefile_&, it specifies a
 prefix string with which any file named in a &%-C%& command line option must
 
 If ALT_CONFIG_PREFIX is defined &_in Local/Makefile_&, it specifies a
 prefix string with which any file named in a &%-C%& command line option must


@@ -4532,6 +4578,18 @@ non-privileged user causes Exim to discard its root privilege.
 If DISABLE_D_OPTION is defined in &_Local/Makefile_&, the use of &%-D%& is
 completely disabled, and its use causes an immediate error exit.
 
 If DISABLE_D_OPTION is defined in &_Local/Makefile_&, the use of &%-D%& is
 completely disabled, and its use causes an immediate error exit.
 

+.new
+The WHITELIST_D_MACROS option in &_Local/Makefile_& permits the binary builder
+to declare certain macro names trusted, such that root privilege will not
+necessarily be discarded.
+WHITELIST_D_MACROS defines a colon-separated list of macros which are
+considered safe and, if &%-D%& only supplies macros from this list, and the
+values are acceptable, then Exim will not give up root privilege if the caller
+is root, the Exim run-time user, or the CONFIGURE_OWNER, if set.  This is a
+transition mechanism and is expected to be removed in the future.  Acceptable
+values for the macros satisfy the regexp: &`^[A-Za-z0-9_/.-]*$`&
+.wen
+

 Some sites may wish to use the same Exim binary on different machines that
 share a file system, but to use different configuration files on each machine.
 If CONFIGURE_FILE_USE_NODE is defined in &_Local/Makefile_&, Exim first
 Some sites may wish to use the same Exim binary on different machines that
 share a file system, but to use different configuration files on each machine.
 If CONFIGURE_FILE_USE_NODE is defined in &_Local/Makefile_&, Exim first


@@ -5895,11 +5953,9 @@ password are correct. In the examples it just produces an error message.
 To make the authenticators work, you can use a string expansion
 expression like one of the examples in &<<CHAPplaintext>>&.
 
 To make the authenticators work, you can use a string expansion
 expression like one of the examples in &<<CHAPplaintext>>&.
 

-.new

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

-.wen

 
 .ecindex IIDconfiwal
 
 
 .ecindex IIDconfiwal
 


@@ -5919,14 +5975,12 @@ regular expressions is discussed in many Perl reference books, and also in
 Jeffrey Friedl's &'Mastering Regular Expressions'&, which is published by
 O'Reilly (see &url(http://www.oreilly.com/catalog/regex2/)).
 
 Jeffrey Friedl's &'Mastering Regular Expressions'&, which is published by
 O'Reilly (see &url(http://www.oreilly.com/catalog/regex2/)).
 

-.new

 The documentation for the syntax and semantics of the regular expressions that
 are supported by PCRE is included in the PCRE distribution, and no further
 description is included here. The PCRE functions are called from Exim using
 the default option settings (that is, with no PCRE options set), except that
 the PCRE_CASELESS option is set when the matching is required to be
 case-insensitive.
 The documentation for the syntax and semantics of the regular expressions that
 are supported by PCRE is included in the PCRE distribution, and no further
 description is included here. The PCRE functions are called from Exim using
 the default option settings (that is, with no PCRE options set), except that
 the PCRE_CASELESS option is set when the matching is required to be
 case-insensitive.

-.wen

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


@@ -6638,6 +6692,18 @@ ${lookup dnsdb{>: a=host1.example}}
 It is permitted to specify a space as the separator character. Further
 white space is ignored.
 
 It is permitted to specify a space as the separator character. Further
 white space is ignored.
 

+.cindex "TXT record" "in &(dnsdb)& lookup"
+For TXT records with multiple items of data, only the first item is returned,
+unless a separator for them is specified using a comma after the separator
+character followed immediately by the TXT record item separator. To concatenate
+items without a separator, use a semicolon instead.
+.code
+${lookup dnsdb{>\n,: txt=a.b.example}}
+${lookup dnsdb{>\n; txt=a.b.example}}
+.endd
+It is permitted to specify a space as the separator character. Further
+white space is ignored.
+

 .section "Pseudo dnsdb record types" "SECID66"
 .cindex "MX record" "in &(dnsdb)& lookup"
 By default, both the preference value and the host name are returned for
 .section "Pseudo dnsdb record types" "SECID66"
 .cindex "MX record" "in &(dnsdb)& lookup"
 By default, both the preference value and the host name are returned for


@@ -9589,6 +9655,34 @@ For single-key lookup types, no quoting is ever necessary and this operator
 yields an unchanged string.
 
 
 yields an unchanged string.
 
 

+.vitem &*${randint:*&<&'n'&>&*}*&
+.cindex "random number"
+This operator returns a somewhat random number which is less than the
+supplied number and is at least 0.  The quality of this randomness depends
+on how Exim was built; the values are not suitable for keying material.
+If Exim is linked against OpenSSL then RAND_pseudo_bytes() is used.
+Otherwise, the implementation may be arc4random(), random() seeded by
+srandomdev() or srandom(), or a custom implementation even weaker than
+random().
+
+
+.new
+.vitem &*${reverse_ip:*&<&'ipaddr'&>&*}*&
+.cindex "expansion" "IP address"
+This operator reverses an IP address; for IPv4 addresses, the result is in
+dotted-quad decimal form, while for IPv6 addreses the result is in
+dotted-nibble hexadecimal form.  In both cases, this is the "natural" form
+for DNS.  For example,
+.code
+${reverse_ip:192.0.2.4} and ${reverse_ip:2001:0db8:c42:9:1:abcd:192.0.2.3}
+.endd
+returns
+.code
+4.2.0.192 and 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
+.endd
+.wen
+
+

 .vitem &*${rfc2047:*&<&'string'&>&*}*&
 .cindex "expansion" "RFC 2047"
 .cindex "RFC 2047" "expansion operator"
 .vitem &*${rfc2047:*&<&'string'&>&*}*&
 .cindex "expansion" "RFC 2047"
 .cindex "RFC 2047" "expansion operator"


@@ -9750,6 +9844,7 @@ lower case), signifying multiplication by 1024 or 1024*1024, respectively.
 As a special case, the numerical value of an empty string is taken as
 zero.
 
 As a special case, the numerical value of an empty string is taken as
 zero.
 

+

 .new
 .vitem &*bool&~{*&<&'string'&>&*}*&
 .cindex "expansion" "boolean parsing"
 .new
 .vitem &*bool&~{*&<&'string'&>&*}*&
 .cindex "expansion" "boolean parsing"


@@ -9757,17 +9852,29 @@ zero.
 This condition turns a string holding a true or false representation into
 a boolean state.  It parses &"true"&, &"false"&, &"yes"& and &"no"&
 (case-insensitively); also positive integer numbers map to true if non-zero,
 This condition turns a string holding a true or false representation into
 a boolean state.  It parses &"true"&, &"false"&, &"yes"& and &"no"&
 (case-insensitively); also positive integer numbers map to true if non-zero,

-false if zero.  Leading whitespace is ignored.
+false if zero.  Leading and trailing whitespace is ignored.

 All other string values will result in expansion failure.
 
 When combined with ACL variables, this expansion condition will let you
 make decisions in one place and act on those decisions in another place.
 All other string values will result in expansion failure.
 
 When combined with ACL variables, this expansion condition will let you
 make decisions in one place and act on those decisions in another place.

-For example,
+For example:

 .code
 ${if bool{$acl_m_privileged_sender} ...
 .endd
 .wen
 
 .code
 ${if bool{$acl_m_privileged_sender} ...
 .endd
 .wen
 

+
+.vitem &*bool_lax&~{*&<&'string'&>&*}*&
+.cindex "expansion" "boolean parsing"
+.cindex "&%bool_lax%& expansion condition"
+Like &%bool%&, this condition turns a string into a boolean state.  But
+where &%bool%& accepts a strict set of strings, &%bool_lax%& uses the same
+loose definition that the Router &%condition%& option uses.  The empty string
+and the values &"false"&, &"no"& and &"0"& map to false, all others map to
+true.  Leading and trailing whitespace is ignored.
+
+Note that where &"bool{00}"& is false, &"bool_lax{00}"& is true.
+

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


@@ -10219,12 +10326,10 @@ configuration, you might have this:
 .code
 server_condition = ${if pwcheck{$auth1:$auth2}}
 .endd
 .code
 server_condition = ${if pwcheck{$auth1:$auth2}}
 .endd

-.new

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

-.wen

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


@@ -11011,12 +11116,10 @@ doing a delivery in maildir format, the value of &$message_size$& is the
 precise size of the file that has been written. See also
 &$message_body_size$&, &$body_linecount$&, and &$body_zerocount$&.
 
 precise size of the file that has been written. See also
 &$message_body_size$&, &$body_linecount$&, and &$body_zerocount$&.
 

-.new

 .cindex "RCPT" "value of &$message_size$&"
 While running a per message ACL (mail/rcpt/predata), &$message_size$&
 contains the size supplied on the MAIL command, or -1 if no size was given. The
 value may not, of course, be truthful.
 .cindex "RCPT" "value of &$message_size$&"
 While running a per message ACL (mail/rcpt/predata), &$message_size$&
 contains the size supplied on the MAIL command, or -1 if no size was given. The
 value may not, of course, be truthful.

-.wen

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


@@ -12328,6 +12431,7 @@ listed in more than one group.
 .row &%acl_smtp_auth%&               "ACL for AUTH"
 .row &%acl_smtp_connect%&            "ACL for connection"
 .row &%acl_smtp_data%&               "ACL for DATA"
 .row &%acl_smtp_auth%&               "ACL for AUTH"
 .row &%acl_smtp_connect%&            "ACL for connection"
 .row &%acl_smtp_data%&               "ACL for DATA"

+.row &%acl_smtp_dkim%&               "ACL for DKIM verification"

 .row &%acl_smtp_etrn%&               "ACL for ETRN"
 .row &%acl_smtp_expn%&               "ACL for EXPN"
 .row &%acl_smtp_helo%&               "ACL for EHLO or HELO"
 .row &%acl_smtp_etrn%&               "ACL for ETRN"
 .row &%acl_smtp_expn%&               "ACL for EXPN"
 .row &%acl_smtp_helo%&               "ACL for EHLO or HELO"


@@ -12383,6 +12487,7 @@ listed in more than one group.
 .row &%gnutls_require_mac%&          "control GnuTLS MAC algorithms"
 .row &%gnutls_require_protocols%&    "control GnuTLS protocols"
 .row &%gnutls_compat_mode%&          "use GnuTLS compatibility mode"
 .row &%gnutls_require_mac%&          "control GnuTLS MAC algorithms"
 .row &%gnutls_require_protocols%&    "control GnuTLS protocols"
 .row &%gnutls_compat_mode%&          "use GnuTLS compatibility mode"

+.row &%openssl_options%&             "adjust OpenSSL compatibility options"

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


@@ -12788,7 +12893,7 @@ It specifies which anti-virus scanner to use. The default value is:
 .code
 sophie:/var/run/sophie
 .endd
 .code
 sophie:/var/run/sophie
 .endd

-If the value of &%av_scanner%& starts with dollar character, it is expanded
+If the value of &%av_scanner%& starts with a dollar character, it is expanded

 before use. See section &<<SECTscanvirus>>& for further details.
 
 
 before use. See section &<<SECTscanvirus>>& for further details.
 
 


@@ -13382,12 +13487,10 @@ server. For details, see section &<<SECTreqciphgnu>>&.
 This option controls the protocols when GnuTLS is used in an Exim
 server. For details, see section &<<SECTreqciphgnu>>&.
 
 This option controls the protocols when GnuTLS is used in an Exim
 server. For details, see section &<<SECTreqciphgnu>>&.
 

-.new

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

-.wen

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


@@ -13944,6 +14047,16 @@ an oversized message is logged in both the main and the reject logs. See also
 the generic transport option &%message_size_limit%&, which limits the size of
 message that an individual transport can process.
 
 the generic transport option &%message_size_limit%&, which limits the size of
 message that an individual transport can process.
 

+.new
+If you use a virus-scanner and set this option to to a value larger than the
+maximum size that your virus-scanner is configured to support, you may get
+failures triggered by large mails.  The right size to configure for the
+virus-scanner depends upon what data is passed and the options in use but it's
+probably safest to just set it to a little larger than this value.  Eg, with a
+default Exim message size of 50M and a default ClamAV StreamMaxLength of 10M,
+some problems may result.
+.wen
+

 
 .option move_frozen_messages main boolean false
 .cindex "frozen messages" "moving"
 
 .option move_frozen_messages main boolean false
 .cindex "frozen messages" "moving"


@@ -13996,6 +14109,38 @@ harm. This option overrides the &%pipe_as_creator%& option of the &(pipe)&
 transport driver.
 
 
 transport driver.
 
 

+.new
+.option openssl_options main "string list" +dont_insert_empty_fragments
+.cindex "OpenSSL "compatibility options"
+This option allows an administrator to adjust the SSL options applied
+by OpenSSL to connections.  It is given as a space-separated list of items,
+each one to be +added or -subtracted from the current value.  The default
+value is one option which happens to have been set historically.  You can
+remove all options with:
+.code
+openssl_options = -all
+.endd
+This option is only available if Exim is built against OpenSSL.  The values
+available for this option vary according to the age of your OpenSSL install.
+The &"all"& value controls a subset of flags which are available, typically
+the bug workaround options.  The &'SSL_CTX_set_options'& man page will
+list the values known on your system and Exim should support all the
+&"bug workaround"& options and many of the &"modifying"& options.  The Exim
+names lose the leading &"SSL_OP_"& and are lower-cased.
+
+Note that adjusting the options can have severe impact upon the security of
+SSL as used by Exim.  It is possible to disable safety checks and shoot
+yourself in the foot in various unpleasant ways.  This option should not be
+adjusted lightly.  An unrecognised item will be detected at by invoking Exim
+with the &%-bV%& flag.
+
+An example:
+.code
+openssl_options = -all +microsoft_big_sslv3_buffer
+.endd
+.wen
+
+

 .option oracle_servers main "string list" unset
 .cindex "Oracle" "server list"
 This option provides a list of Oracle servers and associated connection data,
 .option oracle_servers main "string list" unset
 .cindex "Oracle" "server list"
 This option provides a list of Oracle servers and associated connection data,


@@ -15096,11 +15241,13 @@ contains the pipe command.
 This specifies the transport driver that is to be used when a &%mail%& command
 is used in a system filter.
 
 This specifies the transport driver that is to be used when a &%mail%& command
 is used in a system filter.
 

+.new

 .option system_filter_user main string unset
 .cindex "uid (user id)" "system filter"
 .option system_filter_user main string unset
 .cindex "uid (user id)" "system filter"

-If this option is not set, the system filter is run in the main Exim delivery
-process, as root. When the option is set, the system filter runs in a separate
-process, as the given user. Unless the string consists entirely of digits, it
+If this option is set to root, the system filter is run in the main Exim
+delivery process, as root.  Otherwise, the system filter runs in a separate
+process, as the given user, defaulting to the Exim run-time user.
+Unless the string consists entirely of digits, it

 is looked up in the password data. Failure to find the named user causes a
 configuration error. The gid is either taken from the password data, or
 specified by &%system_filter_group%&. When the uid is specified numerically,
 is looked up in the password data. Failure to find the named user causes a
 configuration error. The gid is either taken from the password data, or
 specified by &%system_filter_group%&. When the uid is specified numerically,


@@ -15108,8 +15255,8 @@ specified by &%system_filter_group%&. When the uid is specified numerically,
 
 If the system filter generates any pipe, file, or reply deliveries, the uid
 under which the filter is run is used when transporting them, unless a
 
 If the system filter generates any pipe, file, or reply deliveries, the uid
 under which the filter is run is used when transporting them, unless a

-transport option overrides. Normally you should set &%system_filter_user%& if
-your system filter generates these kinds of delivery.
+transport option overrides.
+.wen

 
 
 .option tcp_nodelay main boolean true
 
 
 .option tcp_nodelay main boolean true


@@ -15591,6 +15738,11 @@ router is skipped, and the address is offered to the next one.
 If the result is any other value, the router is run (as this is the last
 precondition to be evaluated, all the other preconditions must be true).
 
 If the result is any other value, the router is run (as this is the last
 precondition to be evaluated, all the other preconditions must be true).
 

+.new
+This option is unique in that multiple &%condition%& options may be present.
+All &%condition%& options must succeed.
+.wen
+

 The &%condition%& option provides a means of applying custom conditions to the
 running of routers. Note that in the case of a simple conditional expansion,
 the default expansion values are exactly what is wanted. For example:
 The &%condition%& option provides a means of applying custom conditions to the
 running of routers. Note that in the case of a simple conditional expansion,
 the default expansion values are exactly what is wanted. For example:


@@ -15601,6 +15753,14 @@ Because of the default behaviour of the string expansion, this is equivalent to
 .code
 condition = ${if >{$message_age}{600}{true}{}}
 .endd
 .code
 condition = ${if >{$message_age}{600}{true}{}}
 .endd

+.new
+A multiple condition example, which succeeds:
+.code
+condition = ${if >{$message_age}{600}}
+condition = ${if !eq{${lc:$local_part}}{postmaster}}
+condition = foobar
+.endd
+.wen

 If the expansion fails (other than forced failure) delivery is deferred. Some
 of the other precondition options are common special cases that could in fact
 be specified using &%condition%&.
 If the expansion fails (other than forced failure) delivery is deferred. Some
 of the other precondition options are common special cases that could in fact
 be specified using &%condition%&.


@@ -17861,12 +18021,10 @@ redirection items of the form
 :defer:
 :fail:
 .endd
 :defer:
 :fail:
 .endd

-.new

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

-.wen

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


@@ -19010,12 +19168,10 @@ destination. The process that writes the message to the filter, the
 filter itself, and the original process that reads the result and delivers it
 are all run in parallel, like a shell pipeline.
 
 filter itself, and the original process that reads the result and delivers it
 are all run in parallel, like a shell pipeline.
 

-.new

 The filter can perform any transformations it likes, but of course should take
 care not to break RFC 2822 syntax. Exim does not check the result, except to
 test for a final newline when SMTP is in use. All messages transmitted over
 SMTP must end with a newline, so Exim supplies one if it is missing.
 The filter can perform any transformations it likes, but of course should take
 care not to break RFC 2822 syntax. Exim does not check the result, except to
 test for a final newline when SMTP is in use. All messages transmitted over
 SMTP must end with a newline, so Exim supplies one if it is missing.

-.wen

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


@@ -21041,6 +21197,19 @@ sought in the PATH directories, in the usual way. &*Warning*&: This does not
 apply to a command specified as a transport filter.
 
 
 apply to a command specified as a transport filter.
 
 

+.new
+.option permit_coredump pipe boolean false
+Normally Exim inhibits core-dumps during delivery.  If you have a need to get
+a core-dump of a pipe command, enable this command.  This enables core-dumps
+during delivery and affects both the Exim binary and the pipe command run.
+It is recommended that this option remain off unless and until you have a need
+for it and that this only be enabled when needed, as the risk of excessive
+resource consumption can be quite high.  Note also that Exim is typically
+installed as a setuid binary and most operating systems will inhibit coredumps
+of these by default, so further OS-specific action may be required.
+.wen
+
+

 .option pipe_as_creator pipe boolean false
 .cindex "uid (user id)" "local delivery"
 If the generic &%user%& option is not set and this option is true, the delivery
 .option pipe_as_creator pipe boolean false
 .cindex "uid (user id)" "local delivery"
 If the generic &%user%& option is not set and this option is true, the delivery


@@ -21181,6 +21350,7 @@ procmail_pipe:
   envelope_to_add
   check_string = "From "
   escape_string = ">From "
   envelope_to_add
   check_string = "From "
   escape_string = ">From "

+  umask = 077

   user = $local_part
   group = mail
 
   user = $local_part
   group = mail
 


@@ -21492,12 +21662,10 @@ client. For details, see section &<<SECTreqciphgnu>>&.
 This option controls the protocols when GnuTLS is used in an Exim
 client. For details, see section &<<SECTreqciphgnu>>&.
 
 This option controls the protocols when GnuTLS is used in an Exim
 client. For details, see section &<<SECTreqciphgnu>>&.
 

-.new

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

-.wen

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


@@ -23591,7 +23759,6 @@ login:
              ldap://ldap.example.org/} }} }
   server_set_id = uid=$auth1,ou=people,o=example.org
 .endd
              ldap://ldap.example.org/} }} }
   server_set_id = uid=$auth1,ou=people,o=example.org
 .endd

-.new

 We have to check that the username is not empty before using it, because LDAP
 does not permit empty DN components. We must also use the &%quote_ldap_dn%&
 operator to correctly quote the DN for authentication. However, the basic
 We have to check that the username is not empty before using it, because LDAP
 does not permit empty DN components. We must also use the &%quote_ldap_dn%&
 operator to correctly quote the DN for authentication. However, the basic


@@ -23599,7 +23766,6 @@ operator to correctly quote the DN for authentication. However, the basic
 correct one to use for the password, because quoting is needed only to make
 the password conform to the Exim syntax. At the LDAP level, the password is an
 uninterpreted string.
 correct one to use for the password, because quoting is needed only to make
 the password conform to the Exim syntax. At the LDAP level, the password is an
 uninterpreted string.

-.wen

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


@@ -24491,13 +24657,11 @@ list of permitted cipher suites. If either of these checks fails, delivery to
 the current host is abandoned, and the &(smtp)& transport tries to deliver to
 alternative hosts, if any.
 
 the current host is abandoned, and the &(smtp)& transport tries to deliver to
 alternative hosts, if any.
 

-.new

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

-.wen

 
 .vindex "&$host$&"
 .vindex "&$host_address$&"
 
 .vindex "&$host$&"
 .vindex "&$host_address$&"


@@ -24833,7 +24997,6 @@ client are given temporary error responses until QUIT is received or the
 connection is closed. In these special cases, the QUIT ACL does not run.
 
 
 connection is closed. In these special cases, the QUIT ACL does not run.
 
 

-.new

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


@@ -24841,7 +25004,6 @@ an SMTP session ends without sending QUIT. However, when Exim itself is is bad
 trouble, such as being unable to write to its log files, this ACL is not run,
 because it might try to do things (such as write to log files) that make the
 situation even worse.
 trouble, such as being unable to write to its log files, this ACL is not run,
 because it might try to do things (such as write to log files) that make the
 situation even worse.

-.wen

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


@@ -25700,6 +25862,25 @@ warn  control = caseful_local_part
 Notice that we put back the lower cased version afterwards, assuming that
 is what is wanted for subsequent tests.
 
 Notice that we put back the lower cased version afterwards, assuming that
 is what is wanted for subsequent tests.
 

+.new
+.vitem &*control&~=&~debug/*&<&'options'&>
+.cindex "&ACL;" "enabling debug logging"
+.cindex "debugging" "enabling from an ACL"
+This control turns on debug logging, almost as though Exim had been invoked
+with &`-d`&, with the output going to a new logfile, by default called
+&'debuglog'&.  The filename can be adjusted with the &'tag'& option, which
+may access any variables already defined.  The logging may be adjusted with
+the &'opts'& option, which takes the same values as the &`-d`& command-line
+option.  Some examples (which depend on variables that don't exist in all
+contexts):
+.code
+      control = debug
+      control = debug/tag=.$sender_host_address
+      control = debug/opts=+expand+acl
+      control = debug/tag=.$message_exim_id/opts=+expand
+.endd
+.wen
+

 .vitem &*control&~=&~enforce_sync*& &&&
        &*control&~=&~no_enforce_sync*&
 .cindex "SMTP" "synchronization checking"
 .vitem &*control&~=&~enforce_sync*& &&&
        &*control&~=&~no_enforce_sync*&
 .cindex "SMTP" "synchronization checking"


@@ -27623,12 +27804,10 @@ the third string (in this case &"1"&), whether or not the cryptographic and
 timeout checks succeed. The &$prvscheck_result$& variable contains the result
 of the checks (empty for failure, &"1"& for success).
 
 timeout checks succeed. The &$prvscheck_result$& variable contains the result
 of the checks (empty for failure, &"1"& for success).
 

-.new

 There is one more issue you must consider when implementing prvs-signing:
 you have to ensure that the routers accept prvs-signed addresses and
 deliver them correctly. The easiest way to handle this is to use a &(redirect)&
 router to remove the signature with a configuration along these lines:
 There is one more issue you must consider when implementing prvs-signing:
 you have to ensure that the routers accept prvs-signed addresses and
 deliver them correctly. The easiest way to handle this is to use a &(redirect)&
 router to remove the signature with a configuration along these lines:

-.wen

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


@@ -27824,7 +28003,7 @@ If you do not set &%av_scanner%&, it defaults to
 .code
 av_scanner = sophie:/var/run/sophie
 .endd
 .code
 av_scanner = sophie:/var/run/sophie
 .endd

-If the value of &%av_scanner%& starts with dollar character, it is expanded
+If the value of &%av_scanner%& starts with a dollar character, it is expanded

 before use. The following scanner types are supported in this release:
 
 .vlist
 before use. The following scanner types are supported in this release:
 
 .vlist


@@ -27848,8 +28027,16 @@ required: either the path and name of a UNIX socket file, or a hostname or IP
 number, and a port, separated by space, as in the second of these examples:
 .code
 av_scanner = clamd:/opt/clamd/socket
 number, and a port, separated by space, as in the second of these examples:
 .code
 av_scanner = clamd:/opt/clamd/socket

-av_scanner = clamd:192.168.2.100 1234
-.endd
+av_scanner = clamd:192.0.2.3 1234
+av_scanner = clamd:192.0.2.3 1234:local
+.endd
+If the value of av_scanner points to a UNIX socket file or contains the local
+keyword, then the ClamAV interface will pass a filename containing the data
+to be scanned, which will should normally result in less I/O happening and be
+more efficient.  Normally in the TCP case, the data is streamed to ClamAV as
+Exim does not assume that there is a common filesystem with the remote host.
+There is an option WITH_OLD_CLAMAV_STREAM in &_src/EDITME_& available, should
+you be running a version of ClamAV prior to 0.95.

 If the option is unset, the default is &_/tmp/clamd_&. Thanks to David Saez for
 contributing the code for this scanner.
 
 If the option is unset, the default is &_/tmp/clamd_&. Thanks to David Saez for
 contributing the code for this scanner.
 


@@ -27989,6 +28176,11 @@ If your virus scanner cannot unpack MIME and TNEF containers itself, you should
 use the &%demime%& condition (see section &<<SECTdemimecond>>&) before the
 &%malware%& condition.
 
 use the &%demime%& condition (see section &<<SECTdemimecond>>&) before the
 &%malware%& condition.
 

+.new
+Beware the interaction of Exim's &%message_size_limit%& with any size limits
+imposed by your anti-virus scanner.
+.wen
+

 Here is a very simple scanning example:
 .code
 deny message = This message contains malware ($malware_name)
 Here is a very simple scanning example:
 .code
 deny message = This message contains malware ($malware_name)


@@ -28109,11 +28301,12 @@ SpamAssassin profile has been matched or exceeded. If you want to use the
 &%spam%& condition for its side effects (see the variables below), you can make
 it always return &"true"& by appending &`:true`& to the username.
 
 &%spam%& condition for its side effects (see the variables below), you can make
 it always return &"true"& by appending &`:true`& to the username.
 

+.new

 .cindex "spam scanning" "returned variables"
 When the &%spam%& condition is run, it sets up a number of expansion
 .cindex "spam scanning" "returned variables"
 When the &%spam%& condition is run, it sets up a number of expansion

-variables. With the exception of &$spam_score_int$&, these are usable only
-within ACLs; their values are not retained with the message and so cannot be
-used at delivery time.
+variables. These variables are saved with the received message, thus they are
+available for use at delivery time.
+.wen

 
 .vlist
 .vitem &$spam_score$&
 
 .vlist
 .vitem &$spam_score$&


@@ -28124,11 +28317,8 @@ for inclusion in log or reject messages.
 The spam score of the message, multiplied by ten, as an integer value. For
 example &"34"& or &"305"&. It may appear to disagree with &$spam_score$&
 because &$spam_score$& is rounded and &$spam_score_int$& is truncated.
 The spam score of the message, multiplied by ten, as an integer value. For
 example &"34"& or &"305"&. It may appear to disagree with &$spam_score$&
 because &$spam_score$& is rounded and &$spam_score_int$& is truncated.

-The integer value is useful for numeric comparisons in
-conditions. This variable is special; its value is saved with the message, and
-written to Exim's spool file. This means that it can be used during the whole
-life of the message on your Exim system, in particular, in routers or
-transports during the later delivery phase.
+The integer value is useful for numeric comparisons in conditions.
+

 
 .vitem &$spam_bar$&
 A string consisting of a number of &"+"& or &"-"& characters, representing the
 
 .vitem &$spam_bar$&
 A string consisting of a number of &"+"& or &"-"& characters, representing the


@@ -30328,8 +30518,8 @@ If a message contains a number of different addresses, all those with the same
 characteristics (for example, the same envelope sender) that resolve to the
 same set of hosts, in the same order, are sent in a single SMTP transaction,
 even if they are for different domains, unless there are more than the setting
 characteristics (for example, the same envelope sender) that resolve to the
 same set of hosts, in the same order, are sent in a single SMTP transaction,
 even if they are for different domains, unless there are more than the setting

-of the &%max_rcpts%& option in the &(smtp)& transport allows, in which case
-they are split into groups containing no more than &%max_rcpts%& addresses
+of the &%max_rcpt%&s option in the &(smtp)& transport allows, in which case
+they are split into groups containing no more than &%max_rcpt%&s addresses

 each. If &%remote_max_parallel%& is greater than one, such groups may be sent
 in parallel sessions. The order of hosts with identical MX values is not
 significant when checking whether addresses can be batched in this way.
 each. If &%remote_max_parallel%& is greater than one, such groups may be sent
 in parallel sessions. The order of hosts with identical MX values is not
 significant when checking whether addresses can be batched in this way.


@@ -30815,8 +31005,8 @@ rejected (there seems little point) but instead just get qualified. HELO
 and EHLO act as RSET; VRFY, EXPN, ETRN and  HELP, act
 as NOOP; QUIT quits.
 
 and EHLO act as RSET; VRFY, EXPN, ETRN and  HELP, act
 as NOOP; QUIT quits.
 

-No policy checking is done for BSMTP input. That is, no ACL is run at anytime.
-In this respect it is like non-SMTP local input.
+Minimal policy checking is done for BSMTP input. Only the non-SMTP
+ACL is run in the same way as for non-SMTP local input.

 
 If an error is detected while reading a message, including a missing &"."& at
 the end, Exim gives up immediately. It writes details of the error to the
 
 If an error is detected while reading a message, including a missing &"."& at
 the end, Exim gives up immediately. It writes details of the error to the


@@ -33667,15 +33857,26 @@ which only root has access, this guards against someone who has broken
 into the Exim account from running a privileged Exim with an arbitrary
 configuration file, and using it to break into other accounts.
 .next
 into the Exim account from running a privileged Exim with an arbitrary
 configuration file, and using it to break into other accounts.
 .next

-If ALT_CONFIG_ROOT_ONLY is defined, root privilege is retained for &%-C%&
-and &%-D%& only if the caller of Exim is root. Without it, the Exim user may
-also use &%-C%& and &%-D%& and retain privilege. Setting this option locks out
-the possibility of testing a configuration using &%-C%& right through message
-reception and delivery, even if the caller is root. The reception works, but by
-that time, Exim is running as the Exim user, so when it re-execs to regain
-privilege for the delivery, the use of &%-C%& causes privilege to be lost.
-However, root can test reception and delivery using two separate commands.
-ALT_CONFIG_ROOT_ONLY is not set by default.
+.new
+If a non-trusted configuration file (i.e. not the default configuration file
+or one which is trusted by virtue of being listed in the TRUSTED_CONFIG_LIST
+file) is specified with &%-C%&, or if macros are given with &%-D%& (but see
+the next item), then root privilege is retained only if the caller of Exim is
+root. This locks out the possibility of testing a configuration using &%-C%&
+right through message reception and delivery, even if the caller is root. The
+reception works, but by that time, Exim is running as the Exim user, so when
+it re-execs to regain privilege for the delivery, the use of &%-C%& causes
+privilege to be lost. However, root can test reception and delivery using two
+separate commands.
+.wen
+.next
+The WHITELIST_D_MACROS build option declares some macros to be safe to override
+with &%-D%& if the real uid is one of root, the Exim run-time user or the
+CONFIGURE_OWNER, if defined.  The potential impact of this option is limited by
+requiring the run-time value supplied to &%-D%& to match a regex that errs on
+the restrictive side.  Requiring build-time selection of safe macros is onerous
+but this option is intended solely as a transition mechanism to permit
+previously-working configurations to continue to work after release 4.73.

 .next
 If DISABLE_D_OPTION is defined, the use of the &%-D%& command line option
 is disabled.
 .next
 If DISABLE_D_OPTION is defined, the use of the &%-D%& command line option
 is disabled.


@@ -33731,11 +33932,13 @@ uid and gid in the following cases:
 .oindex "&%-D%&"
 If the &%-C%& option is used to specify an alternate configuration file, or if
 the &%-D%& option is used to define macro values for the configuration, and the
 .oindex "&%-D%&"
 If the &%-C%& option is used to specify an alternate configuration file, or if
 the &%-D%& option is used to define macro values for the configuration, and the

-calling process is not running as root or the Exim user, the uid and gid are
-changed to those of the calling process.
-However, if ALT_CONFIG_ROOT_ONLY is defined in &_Local/Makefile_&, only
-root callers may use &%-C%& and &%-D%& without losing privilege, and if
-DISABLE_D_OPTION is set, the &%-D%& option may not be used at all.
+calling process is not running as root, the uid and gid are changed to those of
+the calling process.
+However, if DISABLE_D_OPTION is defined in &_Local/Makefile_&, the &%-D%&
+option may not be used at all.
+If WHITELIST_D_MACROS is defined in &_Local/Makefile_&, then some macro values
+can be supplied if the calling process is running as root, the Exim run-time
+user or CONFIGURE_OWNER, if defined.

 .next
 .oindex "&%-be%&"
 .oindex "&%-bf%&"
 .next
 .oindex "&%-be%&"
 .oindex "&%-bf%&"


@@ -34341,7 +34544,6 @@ unqualified domain &'foundation'&.
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 
 . ////////////////////////////////////////////////////////////////////////////
 . ////////////////////////////////////////////////////////////////////////////
 

-.new

 .chapter "Support for DKIM (DomainKeys Identified Mail) - RFC4871" "CHID12" &&&
          "DKIM Support"
 .cindex "DKIM"
 .chapter "Support for DKIM (DomainKeys Identified Mail) - RFC4871" "CHID12" &&&
          "DKIM Support"
 .cindex "DKIM"


@@ -34356,7 +34558,7 @@ It can co-exist with all other Exim features, including transport filters.
 .next
 Verify signatures in incoming messages: This is implemented by an additional
 ACL (acl_smtp_dkim), which can be called several times per message, with
 .next
 Verify signatures in incoming messages: This is implemented by an additional
 ACL (acl_smtp_dkim), which can be called several times per message, with

-different signature context.
+different signature contexts.

 .endlist
 
 In typical Exim style, the verification implementation does not include any
 .endlist
 
 In typical Exim style, the verification implementation does not include any


@@ -34384,19 +34586,19 @@ Signing is implemented by setting private options on the SMTP transport.
 These options take (expandable) strings as arguments.
 
 .option dkim_domain smtp string&!! unset
 These options take (expandable) strings as arguments.
 
 .option dkim_domain smtp string&!! unset

-MANDATORY
+MANDATORY:

 The domain you want to sign with. The result of this expanded
 option is put into the &%$dkim_domain%& expansion variable.
 
 .option dkim_selector smtp string&!! unset
 The domain you want to sign with. The result of this expanded
 option is put into the &%$dkim_domain%& expansion variable.
 
 .option dkim_selector smtp string&!! unset

-MANDATORY
+MANDATORY:

 This sets the key selector string. You can use the &%$dkim_domain%& expansion
 variable to look up a matching selector. The result is put in the expansion
 variable &%$dkim_selector%& which should be used in the &%dkim_private_key%&
 option along with &%$dkim_domain%&.
 
 .option dkim_private_key smtp string&!! unset
 This sets the key selector string. You can use the &%$dkim_domain%& expansion
 variable to look up a matching selector. The result is put in the expansion
 variable &%$dkim_selector%& which should be used in the &%dkim_private_key%&
 option along with &%$dkim_domain%&.
 
 .option dkim_private_key smtp string&!! unset

-MANDATORY
+MANDATORY:

 This sets the private key to use. You can use the &%$dkim_domain%& and
 &%$dkim_selector%& expansion variables to determine the private key to use.
 The result can either
 This sets the private key to use. You can use the &%$dkim_domain%& and
 &%$dkim_selector%& expansion variables to determine the private key to use.
 The result can either


@@ -34412,14 +34614,14 @@ is set.
 .endlist
 
 .option dkim_canon smtp string&!! unset
 .endlist
 
 .option dkim_canon smtp string&!! unset

-OPTIONAL
+OPTIONAL:

 This option sets the canonicalization method used when signing a message.
 The DKIM RFC currently supports two methods: "simple" and "relaxed".
 The option defaults to "relaxed" when unset. Note: the current implementation
 only supports using the same canonicalization method for both headers and body.
 
 .option dkim_strict smtp string&!! unset
 This option sets the canonicalization method used when signing a message.
 The DKIM RFC currently supports two methods: "simple" and "relaxed".
 The option defaults to "relaxed" when unset. Note: the current implementation
 only supports using the same canonicalization method for both headers and body.
 
 .option dkim_strict smtp string&!! unset

-OPTIONAL
+OPTIONAL:

 This  option  defines  how  Exim  behaves  when  signing a message that
 should be signed fails for some reason.  When the expansion evaluates to
 either "1" or "true", Exim will defer. Otherwise Exim will send the message
 This  option  defines  how  Exim  behaves  when  signing a message that
 should be signed fails for some reason.  When the expansion evaluates to
 either "1" or "true", Exim will defer. Otherwise Exim will send the message


@@ -34427,7 +34629,7 @@ unsigned. You can use the &%$dkim_domain%& and &%$dkim_selector%& expansion
 variables here.
 
 .option dkim_sign_headers smtp string&!! unset
 variables here.
 
 .option dkim_sign_headers smtp string&!! unset

-OPTIONAL
+OPTIONAL:

 When set, this option must expand to (or be specified as) a colon-separated
 list of header names. Headers with these names will be included in the message
 signature. When unspecified, the header names recommended in RFC4871 will be
 When set, this option must expand to (or be specified as) a colon-separated
 list of header names. Headers with these names will be included in the message
 signature. When unspecified, the header names recommended in RFC4871 will be


@@ -34453,8 +34655,8 @@ more advanced policies. For that reason, the global option
 The global option &%dkim_verify_signers%& can be set to a colon-separated
 list of DKIM domains or identities for which the ACL &%acl_smtp_dkim%& is
 called. It is expanded when the message has been received. At this point,
 The global option &%dkim_verify_signers%& can be set to a colon-separated
 list of DKIM domains or identities for which the ACL &%acl_smtp_dkim%& is
 called. It is expanded when the message has been received. At this point,

-the expansion variable &%$dkim_signers%& already contains a colon-
-separated list of signer domains and identities for the message. When
+the expansion variable &%$dkim_signers%& already contains a colon-separated
+list of signer domains and identities for the message. When

 &%dkim_verify_signers%& is not specified in the main configuration,
 it defaults as:
 .code
 &%dkim_verify_signers%& is not specified in the main configuration,
 it defaults as:
 .code


@@ -34468,7 +34670,7 @@ dkim_verify_signers = paypal.com:ebay.com:$dkim_signers
 .endd
 This would result in &%acl_smtp_dkim%& always being called for "paypal.com"
 and "ebay.com", plus all domains and identities that have signatures in the message.
 .endd
 This would result in &%acl_smtp_dkim%& always being called for "paypal.com"
 and "ebay.com", plus all domains and identities that have signatures in the message.

-You can also be more creative in constructing your policy. Example:
+You can also be more creative in constructing your policy. For example:

 .code
 dkim_verify_signers = $sender_address_domain:$dkim_signers
 .endd
 .code
 dkim_verify_signers = $sender_address_domain:$dkim_signers
 .endd


@@ -34482,7 +34684,7 @@ available (from most to least important):
 
 .vlist
 .vitem &%$dkim_cur_signer%&
 
 .vlist
 .vitem &%$dkim_cur_signer%&

-The signer that is being evaluated in this ACL run. This can be domain or
+The signer that is being evaluated in this ACL run. This can be a domain or

 an identity. This is one of the list items from the expanded main option
 &%dkim_verify_signers%& (see above).
 .vitem &%$dkim_verify_status%&
 an identity. This is one of the list items from the expanded main option
 &%dkim_verify_signers%& (see above).
 .vitem &%$dkim_verify_status%&


@@ -34527,7 +34729,7 @@ The signing identity, if present. IMPORTANT: This variable is only populated
 if there is an actual signature in the message for the current domain or
 identity (as reflected by &%$dkim_cur_signer%&).
 .vitem &%$dkim_selector%&
 if there is an actual signature in the message for the current domain or
 identity (as reflected by &%$dkim_cur_signer%&).
 .vitem &%$dkim_selector%&

-The key record selector string
+The key record selector string.

 .vitem &%$dkim_algo%&
 The algorithm used. One of 'rsa-sha1' or 'rsa-sha256'.
 .vitem &%$dkim_canon_body%&
 .vitem &%$dkim_algo%&
 The algorithm used. One of 'rsa-sha1' or 'rsa-sha256'.
 .vitem &%$dkim_canon_body%&


@@ -34562,7 +34764,7 @@ in the key record.
 Key granularity (tag g=) from the key record. Defaults to "*" if not specified
 in the key record.
 .vitem &%$dkim_key_notes%&
 Key granularity (tag g=) from the key record. Defaults to "*" if not specified
 in the key record.
 .vitem &%$dkim_key_notes%&

-Notes from the key record (tag n=)
+Notes from the key record (tag n=).

 .endlist
 
 In addition, two ACL conditions are provided:
 .endlist
 
 In addition, two ACL conditions are provided:


@@ -34572,7 +34774,7 @@ In addition, two ACL conditions are provided:
 ACL condition that checks a colon-separated list of domains or identities
 for a match against the domain or identity that the ACL is currently verifying
 (reflected by &%$dkim_cur_signer%&). This is typically used to restrict an ACL
 ACL condition that checks a colon-separated list of domains or identities
 for a match against the domain or identity that the ACL is currently verifying
 (reflected by &%$dkim_cur_signer%&). This is typically used to restrict an ACL

-verb to a group of domains or identities, like:
+verb to a group of domains or identities. For example:

 
 .code
 # Warn when message apparently from GMail has no signature at all
 
 .code
 # Warn when message apparently from GMail has no signature at all


@@ -34598,7 +34800,6 @@ The possible status keywords are: 'none','invalid','fail' and 'pass'. Please
 see the documentation of the &%$dkim_verify_status%& expansion variable above
 for more information of what they mean.
 .endlist
 see the documentation of the &%$dkim_verify_status%& expansion variable above
 for more information of what they mean.
 .endlist

-.wen

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