Doc: add clarification for DKIM example

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 6302f5185581332356963b4e1a07dcc414fd9dbb..54775aecd01c1bffb586bcb42168ba6810f47e5d 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -2627,6 +2627,8 @@ users to set envelope senders.
 
 .cindex "&'From:'& header line"
 .cindex "&'Sender:'& header line"
 
 .cindex "&'From:'& header line"
 .cindex "&'Sender:'& header line"

+.cindex "header lines" "From:"
+.cindex "header lines" "Sender:"

 For a trusted user, there is never any check on the contents of the &'From:'&
 header line, and a &'Sender:'& line is never added. Furthermore, any existing
 &'Sender:'& line in incoming local (non-TCP/IP) messages is not removed.
 For a trusted user, there is never any check on the contents of the &'From:'&
 header line, and a &'Sender:'& line is never added. Furthermore, any existing
 &'Sender:'& line in incoming local (non-TCP/IP) messages is not removed.


@@ -5134,7 +5136,11 @@ with the characters &"0x"&, in which case the remainder is interpreted as a
 hexadecimal number.
 
 If an integer value is followed by the letter K, it is multiplied by 1024; if
 hexadecimal number.
 
 If an integer value is followed by the letter K, it is multiplied by 1024; if

-it is followed by the letter M, it is multiplied by 1024x1024. When the values
+it is followed by the letter M, it is multiplied by 1024x1024;
+.new
+if by the letter G, 1024x1024x1024.
+.wen
+When the values

 of integer option settings are output, values which are an exact multiple of
 1024 or 1024x1024 are sometimes, but not always, printed using the letters K
 and M. The printing style is independent of the actual input format that was
 of integer option settings are output, values which are an exact multiple of
 1024 or 1024x1024 are sometimes, but not always, printed using the letters K
 and M. The printing style is independent of the actual input format that was


@@ -6262,7 +6268,11 @@ Chapter &<<CHAPplaintext>>& covers both.
 Exim supports the use of regular expressions in many of its options. It
 uses the PCRE regular expression library; this provides regular expression
 matching that is compatible with Perl 5. The syntax and semantics of
 Exim supports the use of regular expressions in many of its options. It
 uses the PCRE regular expression library; this provides regular expression
 matching that is compatible with Perl 5. The syntax and semantics of

-regular expressions is discussed in many Perl reference books, and also in
+regular expressions is discussed in
+.new
+online Perl manpages, in
+.wen
+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/)).
 


@@ -10090,6 +10100,21 @@ Last:user@example.com
 user@example.com
 .endd
 
 user@example.com
 .endd
 

+.new
+.vitem &*${base32:*&<&'digits'&>&*}*&
+.cindex "&%base32%& expansion item"
+.cindex "expansion" "conversion to base 32"
+The string must consist entirely of decimal digits. The number is converted to
+base 32 and output as a (empty, for zero) string of characters.
+Only lowercase letters are used.
+
+.vitem &*${base32d:*&<&'base-32&~digits'&>&*}*&
+.cindex "&%base32d%& expansion item"
+.cindex "expansion" "conversion to base 32"
+The string must consist entirely of base-32 digits.
+The number is converted to decimal and output as a string.
+.wen
+

 .vitem &*${base62:*&<&'digits'&>&*}*&
 .cindex "&%base62%& expansion item"
 .cindex "expansion" "conversion to base 62"
 .vitem &*${base62:*&<&'digits'&>&*}*&
 .cindex "&%base62%& expansion item"
 .cindex "expansion" "conversion to base 62"


@@ -10141,6 +10166,15 @@ escape sequences starting with a backslash. Whether characters with the most
 significant bit set (so-called &"8-bit characters"&) count as printing or not
 is controlled by the &%print_topbitchars%& option.
 
 significant bit set (so-called &"8-bit characters"&) count as printing or not
 is controlled by the &%print_topbitchars%& option.
 

+.new
+.vitem &*${escape8bit:*&<&'string'&>&*}*&
+.cindex "expansion" "escaping 8-bit characters"
+.cindex "&%escape8bit%& expansion item"
+If the string contains and characters with the most significant bit set,
+they are converted to escape sequences starting with a backslash.
+Backslashes and DEL characters are also converted.
+.wen
+

 
 .vitem &*${eval:*&<&'string'&>&*}*&&~and&~&*${eval10:*&<&'string'&>&*}*&
 .cindex "expansion" "expression evaluation"
 
 .vitem &*${eval:*&<&'string'&>&*}*&&~and&~&*${eval10:*&<&'string'&>&*}*&
 .cindex "expansion" "expression evaluation"


@@ -12973,8 +13007,7 @@ or external command, as described above. It is also used during a
 
 .vitem &$verify_mode$&
 .vindex "&$verify_mode$&"
 
 .vitem &$verify_mode$&
 .vindex "&$verify_mode$&"

-While a router or transport is being run in verify mode
-or for cutthrough delivery,
+While a router or transport is being run in verify mode or for cutthrough delivery,

 contains "S" for sender-verification or "R" for recipient-verification.
 Otherwise, empty.
 
 contains "S" for sender-verification or "R" for recipient-verification.
 Otherwise, empty.
 


@@ -19883,12 +19916,17 @@ list1:   :include:/opt/lists/list1
 .endd
 .next
 .cindex "address redirection" "to black hole"
 .endd
 .next
 .cindex "address redirection" "to black hole"

-Sometimes you want to throw away mail to a particular local part. Making the
-&%data%& option expand to an empty string does not work, because that causes
-the router to decline. Instead, the alias item
+.cindex "delivery" "discard"
+.cindex "delivery" "blackhole"

 .cindex "black hole"
 .cindex "abandoning mail"
 .cindex "black hole"
 .cindex "abandoning mail"

-&':blackhole:'& can be used. It does what its name implies. No delivery is
+Sometimes you want to throw away mail to a particular local part.  Making the
+&%data%& option expand to an empty string does not work, because that causes
+the router to decline. Instead, the alias item
+.code
+:blackhole:
+.endd
+can be used. It does what its name implies. No delivery is

 done, and no error message is generated. This has the same effect as specifying
 &_/dev/null_& as a destination, but it can be independently disabled.
 
 done, and no error message is generated. This has the same effect as specifying
 &_/dev/null_& as a destination, but it can be independently disabled.
 


@@ -28093,7 +28131,7 @@ provides a means of specifying an &"and"& conjunction between conditions. For
 example:
 .code
 deny  dnslists = list1.example
 example:
 .code
 deny  dnslists = list1.example

-dnslists = list2.example
+      dnslists = list2.example

 .endd
 If there are no conditions, the verb is always obeyed. Exim stops evaluating
 the conditions and modifiers when it reaches a condition that fails. What
 .endd
 If there are no conditions, the verb is always obeyed. Exim stops evaluating
 the conditions and modifiers when it reaches a condition that fails. What


@@ -28115,8 +28153,8 @@ after &%endpass%&, the ACL returns &"deny"&. Consider this statement, used to
 check a RCPT command:
 .code
 accept domains = +local_domains
 check a RCPT command:
 .code
 accept domains = +local_domains

-endpass
-verify = recipient
+       endpass
+       verify = recipient

 .endd
 If the recipient domain does not match the &%domains%& condition, control
 passes to the next statement. If it does match, the recipient is verified, and
 .endd
 If the recipient domain does not match the &%domains%& condition, control
 passes to the next statement. If it does match, the recipient is verified, and


@@ -28767,7 +28805,7 @@ Notice that we put back the lower cased version afterwards, assuming that
 is what is wanted for subsequent tests.
 
 
 is what is wanted for subsequent tests.
 
 

-.vitem &*control&~=&~cutthrough_delivery*&
+.vitem &*control&~=&~cutthrough_delivery/*&<&'options'&>

 .cindex "&ACL;" "cutthrough routing"
 .cindex "cutthrough" "requesting"
 This option requests delivery be attempted while the item is being received.
 .cindex "&ACL;" "cutthrough routing"
 .cindex "cutthrough" "requesting"
 This option requests delivery be attempted while the item is being received.


@@ -28807,11 +28845,20 @@ It is not supported for messages received with the SMTP PRDR option in use.
 
 Should the ultimate destination system positively accept or reject the mail,
 a corresponding indication is given to the source system and nothing is queued.
 
 Should the ultimate destination system positively accept or reject the mail,
 a corresponding indication is given to the source system and nothing is queued.

-If there is a temporary error the item is queued for later delivery in the
-usual fashion. If the item is successfully delivered in cutthrough mode
+If the item is successfully delivered in cutthrough mode

 the delivery log lines are tagged with ">>" rather than "=>" and appear
 before the acceptance "<=" line.
 
 the delivery log lines are tagged with ">>" rather than "=>" and appear
 before the acceptance "<=" line.
 

+.new
+If there is a temporary error the item is queued for later delivery in the
+usual fashion.
+This behaviour can be adjusted by appending the option &*defer=*&<&'value'&>
+to the control; the default value is &"spool"& and the alternate value
+&"pass"& copies an SMTP defer response from the target back to the initiator
+and does not queue the message.
+Note that this is independent of any receipient verify conditions in the ACL.
+.wen
+

 Delivery in this mode avoids the generation of a bounce mail to a
 (possibly faked)
 sender when the destination system is doing content-scan based rejection.
 Delivery in this mode avoids the generation of a bounce mail to a
 (possibly faked)
 sender when the destination system is doing content-scan based rejection.


@@ -31555,7 +31602,7 @@ condition defers.
 
 Unix and TCP socket specifications may be mixed in any order.
 Each element of the list is a list itself, space-separated by default
 
 Unix and TCP socket specifications may be mixed in any order.
 Each element of the list is a list itself, space-separated by default

-and changeable in the usual way.
+and changeable in the usual way; take care to not double the separator.

 
 For TCP socket specifications a host name or IP (v4 or v6, but
 subject to list-separator quoting rules) address can be used,
 
 For TCP socket specifications a host name or IP (v4 or v6, but
 subject to list-separator quoting rules) address can be used,


@@ -31682,6 +31729,11 @@ spam bar is 50 characters.
 A multiline text table, containing the full SpamAssassin report for the
 message. Useful for inclusion in headers or reject messages.
 This variable is only usable in a DATA-time ACL.
 A multiline text table, containing the full SpamAssassin report for the
 message. Useful for inclusion in headers or reject messages.
 This variable is only usable in a DATA-time ACL.

+.new
+Beware that SpamAssassin may return non-ASCII characters, especially
+when running in country-specific locales, which are not legal
+unencoded in headers.
+.wen

 
 .vitem &$spam_action$&
 For SpamAssassin either 'reject' or 'no action' depending on the
 
 .vitem &$spam_action$&
 For SpamAssassin either 'reject' or 'no action' depending on the


@@ -33267,6 +33319,7 @@ incoming SMTP message from a source that is not permitted to send them.
 
 .section "Resent- header lines" "SECID220"
 .cindex "&%Resent-%& header lines"
 
 .section "Resent- header lines" "SECID220"
 .cindex "&%Resent-%& header lines"

+.cindex "header lines" "Resent-"

 RFC 2822 makes provision for sets of header lines starting with the string
 &`Resent-`& to be added to a message when it is resent by the original
 recipient to somebody else. These headers are &'Resent-Date:'&,
 RFC 2822 makes provision for sets of header lines starting with the string
 &`Resent-`& to be added to a message when it is resent by the original
 recipient to somebody else. These headers are &'Resent-Date:'&,


@@ -33323,6 +33376,7 @@ existing &'Bcc:'& is not removed.
 
 .section "The Date: header line" "SECID223"
 .cindex "&'Date:'& header line"
 
 .section "The Date: header line" "SECID223"
 .cindex "&'Date:'& header line"

+.cindex "header lines" "Date:"

 If a locally-generated or submission-mode message has no &'Date:'& header line,
 Exim adds one, using the current date and time, unless the
 &%suppress_local_fixups%& control has been specified.
 If a locally-generated or submission-mode message has no &'Date:'& header line,
 Exim adds one, using the current date and time, unless the
 &%suppress_local_fixups%& control has been specified.


@@ -33340,6 +33394,7 @@ messages.
 
 .section "The Envelope-to: header line" "SECID225"
 .cindex "&'Envelope-to:'& header line"
 
 .section "The Envelope-to: header line" "SECID225"
 .cindex "&'Envelope-to:'& header line"

+.cindex "header lines" "Envelope-to:"

 .oindex "&%envelope_to_remove%&"
 &'Envelope-to:'& header lines are not part of the standard RFC 2822 header set.
 Exim can be configured to add them to the final delivery of messages. (See the
 .oindex "&%envelope_to_remove%&"
 &'Envelope-to:'& header lines are not part of the standard RFC 2822 header set.
 Exim can be configured to add them to the final delivery of messages. (See the


@@ -33351,6 +33406,7 @@ messages.
 
 .section "The From: header line" "SECTthefrohea"
 .cindex "&'From:'& header line"
 
 .section "The From: header line" "SECTthefrohea"
 .cindex "&'From:'& header line"

+.cindex "header lines" "From:"

 .cindex "Sendmail compatibility" "&""From""& line"
 .cindex "message" "submission"
 .cindex "submission mode"
 .cindex "Sendmail compatibility" "&""From""& line"
 .cindex "message" "submission"
 .cindex "submission mode"


@@ -33394,6 +33450,7 @@ name as described in section &<<SECTconstr>>&.
 
 .section "The Message-ID: header line" "SECID226"
 .cindex "&'Message-ID:'& header line"
 
 .section "The Message-ID: header line" "SECID226"
 .cindex "&'Message-ID:'& header line"

+.cindex "header lines" "Message-ID:"

 .cindex "message" "submission"
 .oindex "&%message_id_header_text%&"
 If a locally-generated or submission-mode incoming message does not contain a
 .cindex "message" "submission"
 .oindex "&%message_id_header_text%&"
 If a locally-generated or submission-mode incoming message does not contain a


@@ -33409,6 +33466,7 @@ in this header line by setting the &%message_id_header_text%& and/or
 
 .section "The Received: header line" "SECID227"
 .cindex "&'Received:'& header line"
 
 .section "The Received: header line" "SECID227"
 .cindex "&'Received:'& header line"

+.cindex "header lines" "Received:"

 A &'Received:'& header line is added at the start of every message. The
 contents are defined by the &%received_header_text%& configuration option, and
 Exim automatically adds a semicolon and a timestamp to the configured string.
 A &'Received:'& header line is added at the start of every message. The
 contents are defined by the &%received_header_text%& configuration option, and
 Exim automatically adds a semicolon and a timestamp to the configured string.


@@ -33425,6 +33483,7 @@ changed to the time of acceptance, which is (apart from a small delay while the
 
 .section "The References: header line" "SECID228"
 .cindex "&'References:'& header line"
 
 .section "The References: header line" "SECID228"
 .cindex "&'References:'& header line"

+.cindex "header lines" "References:"

 Messages created by the &(autoreply)& transport include a &'References:'&
 header line. This is constructed according to the rules that are described in
 section 3.64 of RFC 2822 (which states that replies should contain such a
 Messages created by the &(autoreply)& transport include a &'References:'&
 header line. This is constructed according to the rules that are described in
 section 3.64 of RFC 2822 (which states that replies should contain such a


@@ -33439,6 +33498,7 @@ incoming message. If there are more than 12, the first one and then the final
 
 .section "The Return-path: header line" "SECID229"
 .cindex "&'Return-path:'& header line"
 
 .section "The Return-path: header line" "SECID229"
 .cindex "&'Return-path:'& header line"

+.cindex "header lines" "Return-path:"

 .oindex "&%return_path_remove%&"
 &'Return-path:'& header lines are defined as something an MTA may insert when
 it does the final delivery of messages. (See the generic &%return_path_add%&
 .oindex "&%return_path_remove%&"
 &'Return-path:'& header lines are defined as something an MTA may insert when
 it does the final delivery of messages. (See the generic &%return_path_add%&


@@ -33451,6 +33511,7 @@ default), Exim removes &'Return-path:'& header lines from incoming messages.
 .section "The Sender: header line" "SECTthesenhea"
 .cindex "&'Sender:'& header line"
 .cindex "message" "submission"
 .section "The Sender: header line" "SECTthesenhea"
 .cindex "&'Sender:'& header line"
 .cindex "message" "submission"

+.cindex "header lines" "Sender:"

 For a locally-originated message from an untrusted user, Exim may remove an
 existing &'Sender:'& header line, and it may add a new one. You can modify
 these actions by setting the &%local_sender_retain%& option true, the
 For a locally-originated message from an untrusted user, Exim may remove an
 existing &'Sender:'& header line, and it may add a new one. You can modify
 these actions by setting the &%local_sender_retain%& option true, the


@@ -35419,6 +35480,7 @@ picked out by the distinctive two-character flags that immediately follow the
 timestamp. The flags are:
 .display
 &`<=`&     message arrival
 timestamp. The flags are:
 .display
 &`<=`&     message arrival

+&`(=`&     message fakereject

 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery
 &`>>`&     cutthrough message delivery
 &`=>`&     normal message delivery
 &`->`&     additional address in same delivery
 &`>>`&     cutthrough message delivery


@@ -38055,14 +38117,14 @@ DKIM is documented in RFC 4871.
 DKIM support is compiled into Exim by default if TLS support is present.
 It can be disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
 
 DKIM support is compiled into Exim by default if TLS support is present.
 It can be disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
 

-Exim's DKIM implementation allows to
+Exim's DKIM implementation allows for

 .olist
 .olist

-Sign outgoing messages: This function is implemented in the SMTP transport.
+Signing outgoing messages: This function is implemented in the SMTP transport.

 It can co-exist with all other Exim features
 (including transport filters)
 except cutthrough delivery.
 .next
 It can co-exist with all other Exim features
 (including transport filters)
 except cutthrough delivery.
 .next

-Verify signatures in incoming messages: This is implemented by an additional
+Verifying 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 contexts.
 .endlist
 ACL (acl_smtp_dkim), which can be called several times per message, with
 different signature contexts.
 .endlist


@@ -38091,7 +38153,7 @@ senders).
 .section "Signing outgoing messages" "SECDKIMSIGN"
 .cindex "DKIM" "signing"
 
 .section "Signing outgoing messages" "SECDKIMSIGN"
 .cindex "DKIM" "signing"
 

-Signing is implemented by setting private options on the SMTP transport.
+Signing is enabled 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


@@ -38201,6 +38263,7 @@ available (from most to least important):
 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).
 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 &%$dkim_verify_status%&
 A string describing the general status of the signature. One of
 .ilist
 .vitem &%$dkim_verify_status%&
 A string describing the general status of the signature. One of
 .ilist


@@ -38215,6 +38278,7 @@ available in &%$dkim_verify_reason%&.
 .next
 &%pass%&: The signature passed verification. It is valid.
 .endlist
 .next
 &%pass%&: The signature passed verification. It is valid.
 .endlist

+

 .vitem &%$dkim_verify_reason%&
 A string giving a little bit more detail when &%$dkim_verify_status%& is either
 "fail" or "invalid". One of
 .vitem &%$dkim_verify_reason%&
 A string giving a little bit more detail when &%$dkim_verify_status%& is either
 "fail" or "invalid". One of


@@ -38234,51 +38298,73 @@ could not be verified. This may mean that headers were modified,
 re-written or otherwise changed in a way which is incompatible with
 DKIM verification. It may of course also mean that the signature is forged.
 .endlist
 re-written or otherwise changed in a way which is incompatible with
 DKIM verification. It may of course also mean that the signature is forged.
 .endlist

+

 .vitem &%$dkim_domain%&
 The signing domain. IMPORTANT: This variable is only populated if there is
 an actual signature in the message for the current domain or identity (as
 reflected by &%$dkim_cur_signer%&).
 .vitem &%$dkim_domain%&
 The signing domain. IMPORTANT: This variable is only populated if there is
 an actual signature in the message for the current domain or identity (as
 reflected by &%$dkim_cur_signer%&).

+

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

+

 .vitem &%$dkim_selector%&
 The key record selector string.
 .vitem &%$dkim_selector%&
 The key record selector string.

+

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

+

 .vitem &%$dkim_canon_body%&
 The body canonicalization method. One of 'relaxed' or 'simple'.
 .vitem &%$dkim_canon_body%&
 The body canonicalization method. One of 'relaxed' or 'simple'.

+

 .vitem &%dkim_canon_headers%&
 The header canonicalization method. One of 'relaxed' or 'simple'.
 .vitem &%dkim_canon_headers%&
 The header canonicalization method. One of 'relaxed' or 'simple'.

+

 .vitem &%$dkim_copiedheaders%&
 A transcript of headers and their values which are included in the signature
 (copied from the 'z=' tag of the signature).
 .vitem &%$dkim_copiedheaders%&
 A transcript of headers and their values which are included in the signature
 (copied from the 'z=' tag of the signature).

+.new
+Note that RFC6376 requires that verification fail if the From: header is
+not included in the signature.  Exim does not enforce this; sites wishing
+strict enforcement should code the check explicitly.
+.wen
+

 .vitem &%$dkim_bodylength%&
 The number of signed body bytes. If zero ("0"), the body is unsigned. If no
 limit was set by the signer, "9999999999999" is returned. This makes sure
 that this variable always expands to an integer value.
 .vitem &%$dkim_bodylength%&
 The number of signed body bytes. If zero ("0"), the body is unsigned. If no
 limit was set by the signer, "9999999999999" is returned. This makes sure
 that this variable always expands to an integer value.

+

 .vitem &%$dkim_created%&
 UNIX timestamp reflecting the date and time when the signature was created.
 When this was not specified by the signer, "0" is returned.
 .vitem &%$dkim_created%&
 UNIX timestamp reflecting the date and time when the signature was created.
 When this was not specified by the signer, "0" is returned.

+

 .vitem &%$dkim_expires%&
 UNIX timestamp reflecting the date and time when the signer wants the
 signature to be treated as "expired". When this was not specified by the
 signer, "9999999999999" is returned. This makes it possible to do useful
 integer size comparisons against this value.
 .vitem &%$dkim_expires%&
 UNIX timestamp reflecting the date and time when the signer wants the
 signature to be treated as "expired". When this was not specified by the
 signer, "9999999999999" is returned. This makes it possible to do useful
 integer size comparisons against this value.

+

 .vitem &%$dkim_headernames%&
 A colon-separated list of names of headers included in the signature.
 .vitem &%$dkim_headernames%&
 A colon-separated list of names of headers included in the signature.

+

 .vitem &%$dkim_key_testing%&
 "1" if the key record has the "testing" flag set, "0" if not.
 .vitem &%$dkim_key_testing%&
 "1" if the key record has the "testing" flag set, "0" if not.

+

 .vitem &%$dkim_key_nosubdomains%&
 "1" if the key record forbids subdomaining, "0" otherwise.
 .vitem &%$dkim_key_nosubdomains%&
 "1" if the key record forbids subdomaining, "0" otherwise.

+

 .vitem &%$dkim_key_srvtype%&
 Service type (tag s=) from the key record. Defaults to "*" if not specified
 in the key record.
 .vitem &%$dkim_key_srvtype%&
 Service type (tag s=) from the key record. Defaults to "*" if not specified
 in the key record.

+

 .vitem &%$dkim_key_granularity%&
 Key granularity (tag g=) from the key record. Defaults to "*" if not specified
 in the key record.
 .vitem &%$dkim_key_granularity%&
 Key granularity (tag g=) from the key record. Defaults to "*" if not specified
 in the key record.

+

 .vitem &%$dkim_key_notes%&
 Notes from the key record (tag n=).
 .vitem &%$dkim_key_notes%&
 Notes from the key record (tag n=).

+

 .vitem &%$dkim_key_length%&
 Number of bits in the key.
 .endlist
 .vitem &%$dkim_key_length%&
 Number of bits in the key.
 .endlist


@@ -38293,13 +38379,18 @@ for a match against the domain or identity that the ACL is currently verifying
 verb to a group of domains or identities. For example:
 
 .code
 verb to a group of domains or identities. For example:
 
 .code

-# Warn when Mail purportedly from GMail has no signature at all
-warn log_message = GMail sender without DKIM signature
+# Warn when Mail purportedly from GMail has no gmail signature
+warn log_message = GMail sender without gmail.com DKIM signature

      sender_domains = gmail.com
      dkim_signers = gmail.com
      dkim_status = none
 .endd
 
      sender_domains = gmail.com
      dkim_signers = gmail.com
      dkim_status = none
 .endd
 

+.new
+Note that the above does not check for a total lack of DKIM signing;
+for that check for empty &$h_DKIM-Signature:$& in the data ACL.
+.wen
+

 .vitem &%dkim_status%&
 ACL condition that checks a colon-separated list of possible DKIM verification
 results against the actual result of verification. This is typically used
 .vitem &%dkim_status%&
 ACL condition that checks a colon-separated list of possible DKIM verification
 results against the actual result of verification. This is typically used