Copyright updates:

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index f9bdbd8ec93cb9f8074b8dc7661d1a78a433beae..73624a7bc59eba10c3ac1e8df8004daf71ea8914 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -52,7 +52,7 @@
 .set I   "    "
 
 .macro copyyear
 .set I   "    "
 
 .macro copyyear

-2019
+2020

 .endmacro
 
 . /////////////////////////////////////////////////////////////////////////////
 .endmacro
 
 . /////////////////////////////////////////////////////////////////////////////


@@ -3871,6 +3871,14 @@ This option is not intended for use by external callers. It is used internally
 by Exim in conjunction with the &%-MC%& option. It signifies that the
 remote host supports the ESMTP &_DSN_& extension.
 
 by Exim in conjunction with the &%-MC%& option. It signifies that the
 remote host supports the ESMTP &_DSN_& extension.
 

+.new
+.vitem &%-MCd%&
+.oindex "&%-MCd%&"
+This option is not intended for use by external callers. It is used internally
+by Exim in conjunction with the &%-d%& option
+to pass on an information string on the purpose of the process.
+.wen
+

 .vitem &%-MCG%&&~<&'queue&~name'&>
 .oindex "&%-MCG%&"
 This option is not intended for use by external callers. It is used internally
 .vitem &%-MCG%&&~<&'queue&~name'&>
 .oindex "&%-MCG%&"
 This option is not intended for use by external callers. It is used internally


@@ -6667,6 +6675,10 @@ Two different types of data lookup are implemented:
 The &'single-key'& type requires the specification of a file in which to look,
 and a single key to search for. The key must be a non-empty string for the
 lookup to succeed. The lookup type determines how the file is searched.
 The &'single-key'& type requires the specification of a file in which to look,
 and a single key to search for. The key must be a non-empty string for the
 lookup to succeed. The lookup type determines how the file is searched.

+.new
+.cindex "tainted data" "single-key lookups"
+The file string may not be tainted
+.wen

 .next
 .cindex "query-style lookup" "definition of"
 The &'query-style'& type accepts a generalized database query. No particular
 .next
 .cindex "query-style lookup" "definition of"
 The &'query-style'& type accepts a generalized database query. No particular


@@ -6758,11 +6770,42 @@ by default, but has an option to omit them (see section &<<SECTdbmbuild>>&).
 .next
 .cindex "lookup" "dsearch"
 .cindex "dsearch lookup type"
 .next
 .cindex "lookup" "dsearch"
 .cindex "dsearch lookup type"

-&(dsearch)&: The given file must be a directory; this is searched for an entry
-whose name is the key by calling the &[lstat()]& function. The key may not
-contain any forward slash characters. If &[lstat()]& succeeds, the result of
-the lookup is the name of the entry, which may be a file, directory,
-symbolic link, or any other kind of directory entry. An example of how this
+&(dsearch)&: The given file must be an
+.new
+absolute
+.wen
+directory path; this is searched for an entry
+whose name is the key by calling the &[lstat()]& function.
+The key may not
+contain any forward slash characters.
+If &[lstat()]& succeeds then so does the lookup.
+.new
+.cindex "tainted data" "dsearch result"
+The result is regarded as untainted.
+
+Options for the lookup can be given by appending them after the word "dsearch",
+separated by a comma.  Options, if present, are a comma-separated list having
+each element starting with a tag name and an equals.
+
+Two options are supported, for the return value and for filtering match
+candidates.
+The "ret" option requests an alternate result value of
+the entire path for the entry. Example:
+.code
+${lookup {passwd} dsearch,ret=full {/etc}}
+.endd
+The default result is just the requested entry.
+The "filter" option requests that only directory entries of a given type
+are matched. The match value is one of "file", "dir" or "subdir" (the latter
+not matching "." or ".."). Example:
+.code
+${lookup {passwd} dsearch,filter=file {/etc}}
+.endd
+The default matching is for any entry type, including directories
+and symlinks.
+.wen
+
+An example of how this

 lookup can be used to support virtual domains is given in section
 &<<SECTvirtualdomains>>&.
 .next
 lookup can be used to support virtual domains is given in section
 &<<SECTvirtualdomains>>&.
 .next


@@ -7007,7 +7050,11 @@ passed to a Redis database. See section &<<SECTsql>>&.
 .next
 .cindex "sqlite lookup type"
 .cindex "lookup" "sqlite"
 .next
 .cindex "sqlite lookup type"
 .cindex "lookup" "sqlite"

-&(sqlite)&: The format of the query is a filename followed by an SQL statement
+&(sqlite)&: The format of the query is
+new
+an optional filename
+.wen
+followed by an SQL statement

 that is passed to an SQLite database. See section &<<SECTsqlite>>&.
 
 .next
 that is passed to an SQLite database. See section &<<SECTsqlite>>&.
 
 .next


@@ -7914,6 +7961,11 @@ If any MySQL, PostgreSQL, Oracle, InterBase or Redis lookups are used, the
 or &%redis_servers%&
 option (as appropriate) must be set to a colon-separated list of server
 information.
 or &%redis_servers%&
 option (as appropriate) must be set to a colon-separated list of server
 information.

+.oindex &%mysql_servers%&
+.oindex &%pgsql_servers%&
+.oindex &%oracle_servers%&
+.oindex &%ibase_servers%&
+.oindex &%redis_servers%&

 (For MySQL and PostgreSQL, the global option need not be set if all
 queries contain their own server information &-- see section
 &<<SECTspeserque>>&.)
 (For MySQL and PostgreSQL, the global option need not be set if all
 queries contain their own server information &-- see section
 &<<SECTspeserque>>&.)


@@ -7964,12 +8016,14 @@ The &%quote_redis%& expansion operator
 escapes whitespace and backslash characters with a backslash.
 
 .section "Specifying the server in the query" "SECTspeserque"
 escapes whitespace and backslash characters with a backslash.
 
 .section "Specifying the server in the query" "SECTspeserque"

+.new

 For MySQL, PostgreSQL and Redis lookups (but not currently for Oracle and InterBase),
 it is possible to specify a list of servers with an individual query. This is
 For MySQL, PostgreSQL and Redis lookups (but not currently for Oracle and InterBase),
 it is possible to specify a list of servers with an individual query. This is

-done by starting the query with
+done by appending a comma-separated option to the query type:

 .display
 .display

-&`servers=`&&'server1:server2:server3:...'&&`;`&

 .endd
 .endd

+&`,servers=`&&'server1:server2:server3:...'&
+.wen

 Each item in the list may take one of two forms:
 .olist
 If it contains no slashes it is assumed to be just a host name. The appropriate
 Each item in the list may take one of two forms:
 .olist
 If it contains no slashes it is assumed to be just a host name. The appropriate


@@ -7994,14 +8048,25 @@ mysql_servers = slave1/db/name/pw:\
 .endd
 In an updating lookup, you could then write:
 .code
 .endd
 In an updating lookup, you could then write:
 .code

-${lookup mysql{servers=master; UPDATE ...} }
+${lookup mysql,servers=master {UPDATE ...} }

 .endd
 That query would then be sent only to the master server. If, on the other hand,
 the master is not to be used for reading, and so is not present in the global
 option, you can still update it by a query of this form:
 .code
 .endd
 That query would then be sent only to the master server. If, on the other hand,
 the master is not to be used for reading, and so is not present in the global
 option, you can still update it by a query of this form:
 .code

-${lookup pgsql{servers=master/db/name/pw; UPDATE ...} }
+${lookup pgsql,servers=master/db/name/pw {UPDATE ...} }
+.endd
+
+.new
+An older syntax places the servers speciification before the qury,
+semicolon separated:
+.code
+${lookup mysql{servers=master; UPDATE ...} }

 .endd
 .endd

+The new version avoids potential issues with tainted
+arguments in the query, for explicit expansion.
+&*Note*&: server specifications in list-style lookups are still problematic.
+.wen

 
 
 .section "Special MySQL features" "SECID73"
 
 
 .section "Special MySQL features" "SECID73"


@@ -8051,19 +8116,35 @@ affected.
 .cindex "sqlite lookup type"
 SQLite is different to the other SQL lookups because a filename is required in
 addition to the SQL query. An SQLite database is a single file, and there is no
 .cindex "sqlite lookup type"
 SQLite is different to the other SQL lookups because a filename is required in
 addition to the SQL query. An SQLite database is a single file, and there is no

-daemon as in the other SQL databases. The interface to Exim requires the name
-of the file, as an absolute path, to be given at the start of the query. It is
-separated from the query by white space. This means that the path name cannot
-contain white space. Here is a lookup expansion example:
+daemon as in the other SQL databases.
+
+.new
+.oindex &%sqlite_dbfile%&
+The preferred way of specifying the file is by using the
+&%sqlite_dbfile%& option, set to
+an absolute path.
+.wen
+A deprecated method is available, prefixing the query with the filename
+separated by white space.
+This means that the path name cannot contain white space.
+.cindex "tainted data" "sqlite file"
+It also means that the query cannot use any tainted values, as that taints
+the entire query including the filename - resulting in a refusal to open
+the file.
+
+.new
+Here is a lookup expansion example:

 .code
 .code

-${lookup sqlite {/some/thing/sqlitedb \
-  select name from aliases where id='userx';}}
+sqlite_dbfile = /some/thing/sqlitedb
+...
+${lookup sqlite {select name from aliases where id='userx';}}

 .endd
 In a list, the syntax is similar. For example:
 .code
 .endd
 In a list, the syntax is similar. For example:
 .code

-domainlist relay_to_domains = sqlite;/some/thing/sqlitedb \
+domainlist relay_to_domains = sqlite;\

    select * from relays where ip='$sender_host_address';
 .endd
    select * from relays where ip='$sender_host_address';
 .endd

+.wen

 The only character affected by the &%quote_sqlite%& operator is a single
 quote, which it doubles.
 
 The only character affected by the &%quote_sqlite%& operator is a single
 quote, which it doubles.
 


@@ -8551,6 +8632,14 @@ whether or not the query succeeds. However, when a lookup is used for the
 &%domains%& option on a router, the data is preserved in the &$domain_data$&
 variable and can be referred to in other options.
 .next
 &%domains%& option on a router, the data is preserved in the &$domain_data$&
 variable and can be referred to in other options.
 .next

+.new
+If the pattern starts with the name of a lookup type
+of either kind (single-key or query-style) it may be
+followed by a command and options,
+The options are lookup-type specific and consist of a comma-separated list.
+Each item starts with a tag and and equals "=".
+.wen
+.next

 .cindex "domain list" "matching literal domain name"
 If none of the above cases apply, a caseless textual comparison is made
 between the pattern and the domain.
 .cindex "domain list" "matching literal domain name"
 If none of the above cases apply, a caseless textual comparison is made
 between the pattern and the domain.


@@ -10196,21 +10285,37 @@ ${readsocket{/socket/name}{request string}{3s}}
 .endd
 
 The third argument is a list of options, of which the first element is the timeout
 .endd
 
 The third argument is a list of options, of which the first element is the timeout

-and must be present if the argument is given.
+and must be present if any options are given.

 Further elements are options of form &'name=value'&.
 Further elements are options of form &'name=value'&.

-Two option types is currently recognised: shutdown and tls.
-The first defines whether (the default)
-or not a shutdown is done on the connection after sending the request.
-Example, to not do so (preferred, eg. by some webservers):
+Example:

 .code
 ${readsocket{/socket/name}{request string}{3s:shutdown=no}}
 .endd
 .code
 ${readsocket{/socket/name}{request string}{3s:shutdown=no}}
 .endd

-The second, tls, controls the use of TLS on the connection.  Example:
-.code
-${readsocket{/socket/name}{request string}{3s:tls=yes}}
-.endd
-The default is to not use TLS.
+
+.new
+The following option names are recognised:
+.ilist
+&*cache*&
+Defines if the result data can be cached for use by a later identical
+request in the same process.
+Values are &"yes"& or &"no"& (the default).
+If not, all cached results for this connection specification
+will be invalidated.
+
+.next
+&*shutdown*&
+Defines whether or not a write-shutdown is done on the connection after
+sending the request. Values are &"yes"& (the default) or &"no"&
+(preferred, eg. by some webservers).
+
+.next
+&*tls*&
+Controls the use of TLS on the connection.
+Values are &"yes"& or &"no"& (the default).

 If it is enabled, a shutdown as descripbed above is never done.
 If it is enabled, a shutdown as descripbed above is never done.

+.endlist
+.wen
+

 
 A fourth argument allows you to change any newlines that are in the data
 that is read, in the same way as for &%readfile%& (see above). This example
 
 A fourth argument allows you to change any newlines that are in the data
 that is read, in the same way as for &%readfile%& (see above). This example


@@ -13201,6 +13306,18 @@ library, by setting:
 dns_dnssec_ok = 1
 .endd
 
 dns_dnssec_ok = 1
 .endd
 

+.new
+In addition, on Linux with glibc 2.31 or newer the resolver library will
+default to stripping out a successful validation status.
+This will break a previously working Exim installation.
+Provided that you do trust the resolver (ie, is on localhost) you can tell
+glibc to pass through any successful validation with a new option in
+&_/etc/resolv.conf_&:
+.code
+options trust-ad
+.endd
+.wen
+

 Exim does not perform DNSSEC validation itself, instead leaving that to a
 validating resolver (e.g. unbound, or bind with suitable configuration).
 
 Exim does not perform DNSSEC validation itself, instead leaving that to a
 validating resolver (e.g. unbound, or bind with suitable configuration).
 


@@ -14309,6 +14426,7 @@ listed in more than one group.
 .row &%daemon_startup_sleep%&        "time to sleep between tries"
 .row &%extra_local_interfaces%&      "not necessarily listened on"
 .row &%local_interfaces%&            "on which to listen, with optional ports"
 .row &%daemon_startup_sleep%&        "time to sleep between tries"
 .row &%extra_local_interfaces%&      "not necessarily listened on"
 .row &%local_interfaces%&            "on which to listen, with optional ports"

+.row &%notifier_socket%&             "override compiled-in value"

 .row &%pid_file_path%&               "override compiled-in value"
 .row &%queue_run_max%&               "maximum simultaneous queue runners"
 .endtable
 .row &%pid_file_path%&               "override compiled-in value"
 .row &%queue_run_max%&               "maximum simultaneous queue runners"
 .endtable


@@ -14472,6 +14590,7 @@ See also the &'Policy controls'& section above.
 .table2
 .row &%dkim_verify_hashes%&          "DKIM hash methods accepted for signatures"
 .row &%dkim_verify_keytypes%&        "DKIM key types accepted for signatures"
 .table2
 .row &%dkim_verify_hashes%&          "DKIM hash methods accepted for signatures"
 .row &%dkim_verify_keytypes%&        "DKIM key types accepted for signatures"

+.row &%dkim_verify_min_keysizes%&    "DKIM key sizes accepted for signatures"

 .row &%dkim_verify_signers%&         "DKIM domains for which DKIM ACL is run"
 .row &%host_lookup%&                 "host name looked up for these hosts"
 .row &%host_lookup_order%&           "order of DNS and local name lookups"
 .row &%dkim_verify_signers%&         "DKIM domains for which DKIM ACL is run"
 .row &%host_lookup%&                 "host name looked up for these hosts"
 .row &%host_lookup_order%&           "order of DNS and local name lookups"


@@ -15246,6 +15365,16 @@ This option gives a list of key types which are acceptable in signatures,
 and an order of processing.
 Signatures with algorithms not in the list will be ignored.
 
 and an order of processing.
 Signatures with algorithms not in the list will be ignored.
 

+
+.new
+.option dkim_verify_min_keysizes main "string list" "rsa=1024 ed25519=250"
+This option gives a list of key sizes which are acceptable in signatures.
+The list is keyed by the algorithm type for the key; the values are in bits.
+Signatures with keys smaller than given by this option will fail verification.
+
+The default enforces the RFC 8301 minimum key size for RSA signatures.
+.wen
+

 .option dkim_verify_minimal main boolean false
 If set to true, verification of signatures will terminate after the
 first success.
 .option dkim_verify_minimal main boolean false
 If set to true, verification of signatures will terminate after the
 first success.


@@ -15328,6 +15457,18 @@ default. A value of 0 coerces DNSSEC off, a value of 1 coerces DNSSEC on.
 
 If the resolver library does not support DNSSEC then this option has no effect.
 
 
 If the resolver library does not support DNSSEC then this option has no effect.
 

+.new
+On Linux with glibc 2.31 or newer this is insufficient, the resolver library
+will default to stripping out a successful validation status.
+This will break a previously working Exim installation.
+Provided that you do trust the resolver (ie, is on localhost) you can tell
+glibc to pass through any successful validation with a new option in
+&_/etc/resolv.conf_&:
+.code
+options trust-ad
+.endd
+.wen
+

 
 .option dns_ipv4_lookup main "domain list&!!" unset
 .cindex "IPv6" "DNS lookup for AAAA records"
 
 .option dns_ipv4_lookup main "domain list&!!" unset
 .cindex "IPv6" "DNS lookup for AAAA records"


@@ -16382,6 +16523,24 @@ harm. This option overrides the &%pipe_as_creator%& option of the &(pipe)&
 transport driver.
 
 
 transport driver.
 
 

+.new
+.option notifier_socket main string "$spool_directory/exim_daemon_notify"
+This option gives the name for a unix-domain socket on which the daemon
+listens for work and information-requests.
+Only installations running multiple daemons sharing a spool directory
+should need to modify the default.
+
+The option is expanded before use.
+If the platform supports Linux-style abstract socket names, the result
+is used with a nul byte prefixed.
+Otherwise, it should be a full path name and use a directory accessible
+to Exim.
+
+If the Exim command line uses a &%-oX%& option and does not use &%-oP%&
+then a notifier socket is not created.
+.wen
+
+

 .option openssl_options main "string list" "+no_sslv2 +no_sslv3 +single_dh_use +no_ticket +no_renegotiation"
 .cindex "OpenSSL "compatibility options"
 This option allows an administrator to adjust the SSL options applied
 .option openssl_options main "string list" "+no_sslv2 +no_sslv3 +single_dh_use +no_ticket +no_renegotiation"
 .cindex "OpenSSL "compatibility options"
 This option allows an administrator to adjust the SSL options applied


@@ -16847,7 +17006,7 @@ received_header_text = Received: \
         ${if def:sender_helo_name {(helo=$sender_helo_name)\n\t}}}}\
   by $primary_hostname \
   ${if def:received_protocol {with $received_protocol }}\
         ${if def:sender_helo_name {(helo=$sender_helo_name)\n\t}}}}\
   by $primary_hostname \
   ${if def:received_protocol {with $received_protocol }}\

-  ${if def:tls_ver           { ($tls_ver)}}\
+  ${if def:tls_in_ver        { ($tls_in_ver)}}\

   ${if def:tls_in_cipher_std { tls $tls_in_cipher_std\n\t}}\
   (Exim $version_number)\n\t\
   ${if def:sender_address \
   ${if def:tls_in_cipher_std { tls $tls_in_cipher_std\n\t}}\
   (Exim $version_number)\n\t\
   ${if def:sender_address \


@@ -16856,7 +17015,8 @@ received_header_text = Received: \
   ${if def:received_for {\n\tfor $received_for}}
 .endd
 
   ${if def:received_for {\n\tfor $received_for}}
 .endd
 

-The reference to the TLS cipher is omitted when Exim is built without TLS
+The references to the TLS version and cipher are
+omitted when Exim is built without TLS

 support. The use of conditional expansions ensures that this works for both
 locally generated messages and messages received from remote hosts, giving
 header lines such as the following:
 support. The use of conditional expansions ensures that this works for both
 locally generated messages and messages received from remote hosts, giving
 header lines such as the following:


@@ -20155,8 +20315,10 @@ semicolon is the default route list separator.
 
 
 .section "Format of one host item" "SECTformatonehostitem"
 
 
 .section "Format of one host item" "SECTformatonehostitem"

-Each item in the list of hosts is either a host name or an IP address,
-optionally with an attached port number. When no port is given, an IP address
+Each item in the list of hosts can be either a host name or an IP address,
+optionally with an attached port number, or it can be a single "+"
+(see &%hosts_randomize%&).
+When no port is given, an IP address

 is not enclosed in brackets. When a port is specified, it overrides the port
 specification on the transport. The port is separated from the name or address
 by a colon. This leads to some complications:
 is not enclosed in brackets. When a port is specified, it overrides the port
 specification on the transport. The port is separated from the name or address
 by a colon. This leads to some complications:


@@ -33704,13 +33866,22 @@ The following list describes all expansion variables that are
 available in the MIME ACL:
 
 .vlist
 available in the MIME ACL:
 
 .vlist

+.vitem &$mime_anomaly_level$& &&&
+       &$mime_anomaly_text$&
+.vindex &$mime_anomaly_level$&
+.vindex &$mime_anomaly_text$&
+If there are problems decoding, these variables contain information on
+the detected issue.
+

 .vitem &$mime_boundary$&
 .vitem &$mime_boundary$&

-If the current part is a multipart (see &$mime_is_multipart$&) below, it should
+.vindex &$mime_boundary$&
+If the current part is a multipart (see &$mime_is_multipart$& below), it should

 have a boundary string, which is stored in this variable. If the current part
 has no boundary parameter in the &'Content-Type:'& header, this variable
 contains the empty string.
 
 .vitem &$mime_charset$&
 have a boundary string, which is stored in this variable. If the current part
 has no boundary parameter in the &'Content-Type:'& header, this variable
 contains the empty string.
 
 .vitem &$mime_charset$&

+.vindex &$mime_charset$&

 This variable contains the character set identifier, if one was found in the
 &'Content-Type:'& header. Examples for charset identifiers are:
 .code
 This variable contains the character set identifier, if one was found in the
 &'Content-Type:'& header. Examples for charset identifiers are:
 .code


@@ -33722,31 +33893,37 @@ Please note that this value is not normalized, so you should do matches
 case-insensitively.
 
 .vitem &$mime_content_description$&
 case-insensitively.
 
 .vitem &$mime_content_description$&

+.vindex &$mime_content_description$&

 This variable contains the normalized content of the &'Content-Description:'&
 header. It can contain a human-readable description of the parts content. Some
 implementations repeat the filename for attachments here, but they are usually
 only used for display purposes.
 
 .vitem &$mime_content_disposition$&
 This variable contains the normalized content of the &'Content-Description:'&
 header. It can contain a human-readable description of the parts content. Some
 implementations repeat the filename for attachments here, but they are usually
 only used for display purposes.
 
 .vitem &$mime_content_disposition$&

+.vindex &$mime_content_disposition$&

 This variable contains the normalized content of the &'Content-Disposition:'&
 header. You can expect strings like &"attachment"& or &"inline"& here.
 
 .vitem &$mime_content_id$&
 This variable contains the normalized content of the &'Content-Disposition:'&
 header. You can expect strings like &"attachment"& or &"inline"& here.
 
 .vitem &$mime_content_id$&

+.vindex &$mime_content_id$&

 This variable contains the normalized content of the &'Content-ID:'& header.
 This is a unique ID that can be used to reference a part from another part.
 
 .vitem &$mime_content_size$&
 This variable contains the normalized content of the &'Content-ID:'& header.
 This is a unique ID that can be used to reference a part from another part.
 
 .vitem &$mime_content_size$&

+.vindex &$mime_content_size$&

 This variable is set only after the &%decode%& modifier (see above) has been
 successfully run. It contains the size of the decoded part in kilobytes. The
 size is always rounded up to full kilobytes, so only a completely empty part
 has a &$mime_content_size$& of zero.
 
 .vitem &$mime_content_transfer_encoding$&
 This variable is set only after the &%decode%& modifier (see above) has been
 successfully run. It contains the size of the decoded part in kilobytes. The
 size is always rounded up to full kilobytes, so only a completely empty part
 has a &$mime_content_size$& of zero.
 
 .vitem &$mime_content_transfer_encoding$&

+.vindex &$mime_content_transfer_encoding$&

 This variable contains the normalized content of the
 &'Content-transfer-encoding:'& header. This is a symbolic name for an encoding
 type. Typical values are &"base64"& and &"quoted-printable"&.
 
 .vitem &$mime_content_type$&
 This variable contains the normalized content of the
 &'Content-transfer-encoding:'& header. This is a symbolic name for an encoding
 type. Typical values are &"base64"& and &"quoted-printable"&.
 
 .vitem &$mime_content_type$&

+.vindex &$mime_content_type$&

 If the MIME part has a &'Content-Type:'& header, this variable contains its
 value, lowercased, and without any options (like &"name"& or &"charset"&). Here
 are some examples of popular MIME types, as they may appear in this variable:
 If the MIME part has a &'Content-Type:'& header, this variable contains its
 value, lowercased, and without any options (like &"name"& or &"charset"&). Here
 are some examples of popular MIME types, as they may appear in this variable:


@@ -33761,6 +33938,7 @@ If the MIME part has no &'Content-Type:'& header, this variable contains the
 empty string.
 
 .vitem &$mime_decoded_filename$&
 empty string.
 
 .vitem &$mime_decoded_filename$&

+.vindex &$mime_decoded_filename$&

 This variable is set only after the &%decode%& modifier (see above) has been
 successfully run. It contains the full path and filename of the file
 containing the decoded data.
 This variable is set only after the &%decode%& modifier (see above) has been
 successfully run. It contains the full path and filename of the file
 containing the decoded data.


@@ -33769,6 +33947,7 @@ containing the decoded data.
 .cindex "RFC 2047"
 .vlist
 .vitem &$mime_filename$&
 .cindex "RFC 2047"
 .vlist
 .vitem &$mime_filename$&

+.vindex &$mime_filename$&

 This is perhaps the most important of the MIME variables. It contains a
 proposed filename for an attachment, if one was found in either the
 &'Content-Type:'& or &'Content-Disposition:'& headers. The filename will be
 This is perhaps the most important of the MIME variables. It contains a
 proposed filename for an attachment, if one was found in either the
 &'Content-Type:'& or &'Content-Disposition:'& headers. The filename will be


@@ -33779,6 +33958,7 @@ decoded, but no additional sanity checks are done.
 found, this variable contains the empty string.
 
 .vitem &$mime_is_coverletter$&
 found, this variable contains the empty string.
 
 .vitem &$mime_is_coverletter$&

+.vindex &$mime_is_coverletter$&

 This variable attempts to differentiate the &"cover letter"& of an e-mail from
 attached data. It can be used to clamp down on flashy or unnecessarily encoded
 content in the cover letter, while not restricting attachments at all.
 This variable attempts to differentiate the &"cover letter"& of an e-mail from
 attached data. It can be used to clamp down on flashy or unnecessarily encoded
 content in the cover letter, while not restricting attachments at all.


@@ -33811,18 +33991,22 @@ deny message = HTML mail is not accepted here
 condition = $mime_is_coverletter
 condition = ${if eq{$mime_content_type}{text/html}{1}{0}}
 .endd
 condition = $mime_is_coverletter
 condition = ${if eq{$mime_content_type}{text/html}{1}{0}}
 .endd

+

 .vitem &$mime_is_multipart$&
 .vitem &$mime_is_multipart$&

+.vindex &$mime_is_multipart$&

 This variable has the value 1 (true) when the current part has the main type
 &"multipart"&, for example, &"multipart/alternative"& or &"multipart/mixed"&.
 Since multipart entities only serve as containers for other parts, you may not
 want to carry out specific actions on them.
 
 .vitem &$mime_is_rfc822$&
 This variable has the value 1 (true) when the current part has the main type
 &"multipart"&, for example, &"multipart/alternative"& or &"multipart/mixed"&.
 Since multipart entities only serve as containers for other parts, you may not
 want to carry out specific actions on them.
 
 .vitem &$mime_is_rfc822$&

+.vindex &$mime_is_rfc822$&

 This variable has the value 1 (true) if the current part is not a part of the
 checked message itself, but part of an attached message. Attached message
 decoding is fully recursive.
 
 .vitem &$mime_part_count$&
 This variable has the value 1 (true) if the current part is not a part of the
 checked message itself, but part of an attached message. Attached message
 decoding is fully recursive.
 
 .vitem &$mime_part_count$&

+.vindex &$mime_part_count$&

 This variable is a counter that is raised for each processed MIME part. It
 starts at zero for the very first part (which is usually a multipart). The
 counter is per-message, so it is reset when processing RFC822 attachments (see
 This variable is a counter that is raised for each processed MIME part. It
 starts at zero for the very first part (which is usually a multipart). The
 counter is per-message, so it is reset when processing RFC822 attachments (see


@@ -36728,12 +36912,18 @@ to a router of this form:
 virtual:
   driver = redirect
   domains = dsearch;/etc/mail/virtual
 virtual:
   driver = redirect
   domains = dsearch;/etc/mail/virtual

-  data = ${lookup{$local_part}lsearch{/etc/mail/virtual/$domain}}
+  data = ${lookup{$local_part}lsearch{/etc/mail/virtual/$domain_data}}

   no_more
 .endd
   no_more
 .endd

+.new

 The &%domains%& option specifies that the router is to be skipped, unless there
 is a file in the &_/etc/mail/virtual_& directory whose name is the same as the
 The &%domains%& option specifies that the router is to be skipped, unless there
 is a file in the &_/etc/mail/virtual_& directory whose name is the same as the

-domain that is being processed. When the router runs, it looks up the local
+domain that is being processed.
+The &(dsearch)& lookup used results in an untainted version of &$domain$&
+being placed into the &$domain_data$& variable.
+.wen
+
+When the router runs, it looks up the local

 part in the file to find a new address (or list of addresses). The &%no_more%&
 setting ensures that if the lookup fails (leading to &%data%& being an empty
 string), Exim gives up on the address without trying any subsequent routers.
 part in the file to find a new address (or list of addresses). The &%no_more%&
 setting ensures that if the lookup fails (leading to &%data%& being an empty
 string), Exim gives up on the address without trying any subsequent routers.


@@ -40288,7 +40478,7 @@ only supports signing with the same canonicalization method for both headers and
 .option dkim_strict smtp string&!! unset
 This  option  defines  how  Exim  behaves  when  signing a message that
 should be signed fails for some reason.  When the expansion evaluates to
 .option dkim_strict smtp string&!! unset
 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
+either &"1"& or &"true"&, Exim will defer. Otherwise Exim will send the message

 unsigned. You can use the &%$dkim_domain%& and &%$dkim_selector%& expansion
 variables here.
 
 unsigned. You can use the &%$dkim_domain%& and &%$dkim_selector%& expansion
 variables here.
 


@@ -40300,16 +40490,19 @@ in the message signature.
 When unspecified, the header names listed in RFC4871 will be used,
 whether or not each header is present in the message.
 The default list is available for the expansion in the macro
 When unspecified, the header names listed in RFC4871 will be used,
 whether or not each header is present in the message.
 The default list is available for the expansion in the macro

-"_DKIM_SIGN_HEADERS".
+&"_DKIM_SIGN_HEADERS"&
+.new
+and an oversigning variant is in &"_DKIM_OVERSIGN_HEADERS"&.
+.wen

 
 If a name is repeated, multiple headers by that name (or the absence thereof)
 will be signed.  The textually later headers in the headers part of the
 message are signed first, if there are multiples.
 
 
 If a name is repeated, multiple headers by that name (or the absence thereof)
 will be signed.  The textually later headers in the headers part of the
 message are signed first, if there are multiples.
 

-A name can be prefixed with either an '=' or a '+' character.
-If an '=' prefix is used, all headers that are present with this name
+A name can be prefixed with either an &"="& or a &"+"& character.
+If an &"="& prefix is used, all headers that are present with this name

 will be signed.
 will be signed.

-If a '+' prefix if used, all headers that are present with this name
+If a &"+"& prefix if used, all headers that are present with this name

 will be signed, and one signature added for a missing header with the
 name will be appended.
 
 will be signed, and one signature added for a missing header with the
 name will be appended.
 


@@ -40551,6 +40744,10 @@ Notes from the key record (tag n=).
 
 .vitem &%$dkim_key_length%&
 Number of bits in the key.
 
 .vitem &%$dkim_key_length%&
 Number of bits in the key.

+.new
+Valid only once the key is loaded, which is at the time the header signature
+is verified, which is after the body hash is.
+.wen

 
 Note that RFC 8301 says:
 .code
 
 Note that RFC 8301 says:
 .code


@@ -40558,9 +40755,8 @@ Verifiers MUST NOT consider signatures using RSA keys of
 less than 1024 bits as valid signatures.
 .endd
 
 less than 1024 bits as valid signatures.
 .endd
 

-To enforce this you must have a DKIM ACL which checks this variable
-and overwrites the &$dkim_verify_status$& variable as discussed above.
-As EC keys are much smaller, the check should only do this for RSA keys.
+This is enforced by the default setting for the &%dkim_verify_min_keysizes%&
+option.

 
 .endlist
 
 
 .endlist