&*$h_*&<&'header&~name'&>&*:*&" &&&
"&*$bheader_*&<&'header&~name'&>&*:*&&~or&~&&&
&*$bh_*&<&'header&~name'&>&*:*&" &&&
+ "&*$lheader_*&<&'header&~name'&>&*:*&&~or&~&&&
+ &*$lh_*&<&'header&~name'&>&*:*&"
"&*$rheader_*&<&'header&~name'&>&*:*&&~or&~&&&
&*$rh_*&<&'header&~name'&>&*:*&"
.cindex "expansion" "header insertion"
.vindex "&$header_$&"
.vindex "&$bheader_$&"
+.vindex "&$lheader_$&"
.vindex "&$rheader_$&"
.cindex "header lines" "in expansion strings"
.cindex "header lines" "character sets"
internal newlines (caused by splitting the header line over several physical
lines) may be present.
-The difference between &%rheader%&, &%bheader%&, and &%header%& is in the way
+The difference between the four pairs of expansions is in the way
the data in the header line is interpreted.
.ilist
&%rheader%& gives the original &"raw"& content of the header line, with no
processing at all, and without the removal of leading and trailing white space.
+.next
+.cindex "list" "of header lines"
+&%lheader%& gives a colon-separated list, one element per header when there
+are multiple headers with a given name.
+Any embedded colon characters within an element are doubled, so normal Exim
+list-processing facilities can be used.
+The terminating newline of each element is removed; in other respects
+the content is &"raw"&.
+
.next
.cindex "base64 encoding" "in header lines"
&%bheader%& removes leading and trailing white space, and then decodes base64
implementations of TLS.
-option gnutls_allow_auto_pkcs11 main boolean unset
+.option gnutls_allow_auto_pkcs11 main boolean unset
This option will let GnuTLS (2.12.0 or later) autoload PKCS11 modules with
the p11-kit configuration files in &_/etc/pkcs11/modules/_&.
.cindex SSMTP
.cindex SMTPS
This option specifies a list of incoming SSMTP (aka SMTPS) ports that should
-operate the obsolete SSMTP (SMTPS) protocol, where a TLS session is immediately
+operate the SSMTP (SMTPS) protocol, where a TLS session is immediately
set up without waiting for the client to issue a STARTTLS command. For
further details, see section &<<SECTsupobssmt>>&.
a check that the IP being tested is indeed on the first list. The first
domain is the one that is put in &$dnslist_domain$&. For example:
.code
-reject message = \
+deny message = \
rejected because $sender_host_address is blacklisted \
at $dnslist_domain\n$dnslist_text
dnslists = \
given several times, but because the results of the DNS lookups are cached,
the DNS calls themselves are not repeated. For example:
.code
-reject dnslists = \
+deny dnslists = \
http.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.2 : \
socks.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.3 : \
misc.dnsbl.sorbs.net,dnsbl.sorbs.net=127.0.0.4 : \
The &%leaky%& (default) option means that the client's recorded rate is not
updated if it is above the limit. The effect of this is that Exim measures the
-client's average rate of successfully sent email, which cannot be greater than
-the maximum allowed. If the client is over the limit it may suffer some
-counter-measures (as specified in the ACL), but it will still be able to send
-email at the configured maximum rate, whatever the rate of its attempts. This
+client's average rate of successfully sent email,
+.new
+up to the given limit.
+This is appropriate if the countermeasure when the condition is true
+consists of refusing the message, and
is generally the better choice if you have clients that retry automatically.
-For example, it does not prevent a sender with an over-aggressive retry rate
-from getting any email through.
+If the action when true is anything more complex then this option is
+likely not what is wanted.
+.wen
The &%strict%& option means that the client's recorded rate is always
updated. The effect of this is that Exim measures the client's average rate
.section "Building Exim to use a local scan function" "SECID207"
.cindex "&[local_scan()]& function" "building Exim to use"
To make use of the local scan function feature, you must tell Exim where your
-function is before building Exim, by setting LOCAL_SCAN_SOURCE in your
+function is before building Exim, by setting
+.new
+both HAVE_LOCAL_SCAN and
+.wen
+LOCAL_SCAN_SOURCE in your
&_Local/Makefile_&. A recommended place to put it is in the &_Local_&
directory, so you might set
.code
+HAVE_LOCAL_SCAN=yes
LOCAL_SCAN_SOURCE=Local/local_scan.c
.endd
for example. The function must be called &[local_scan()]&. It is called by
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.
+only supports signing with the same canonicalization method for both headers and body.
.option dkim_strict smtp string&!! unset
This option defines how Exim behaves when signing a message that
.section "Verifying DKIM signatures in incoming mail" "SECDKIMVFY"
.cindex "DKIM" "verification"
-Verification of DKIM signatures in SMTP incoming email is implemented via the
-&%acl_smtp_dkim%& ACL. By default, this ACL is called once for each
+.new
+Verification of DKIM signatures in SMTP incoming email is done for all
+messages for which an ACL control &%dkim_disable_verify%& has not been set.
+.cindex authentication "expansion item"
+Performing verification sets up information used by the
+&$authresults$& expansion item.
+.wen
+
+.new The results of that verification are then made available to the
+&%acl_smtp_dkim%& ACL, &new(which can examine and modify them).
+By default, this ACL is called once for each
syntactically(!) correct signature in the incoming message.
A missing ACL definition defaults to accept.
If any ACL call does not accept, the message is not accepted.
If a cutthrough delivery was in progress for the message, that is
summarily dropped (having wasted the transmission effort).
-To evaluate the signature in the ACL a large number of expansion variables
+To evaluate the &new(verification result) in the ACL
+a large number of expansion variables
containing the signature status and its details are set up during the
runtime of the ACL.
-.cindex authentication "expansion item"
-Performing verification sets up information used by the
-&$authresults$& expansion item.
-
Calling the ACL only for existing signatures is not sufficient to build
more advanced policies. For that reason, the global option
&%dkim_verify_signers%&, and a global expansion variable