.cindex "distribution" "signing details"
.cindex "distribution" "public key"
.cindex "public key for signed distribution"
-The distributions are currently signed with Nigel Metheringham's GPG key. The
-corresponding public key is available from a number of keyservers, and there is
-also a copy in the file &_nigel-pubkey.asc_&. The signatures for the tar bundles are
-in:
+.new
+The distributions will be PGP signed by an individual key of the Release
+Coordinator. This key will have a uid containing an email address in the
+&'exim.org'& domain and will have signatures from other people, including
+other Exim maintainers. We expect that the key will be in the "strong set" of
+PGP keys. There should be a trust path to that key from Nigel Metheringham's
+PGP key, a version of which can be found in the release directory in the file
+&_nigel-pubkey.asc_&. All keys used will be available in public keyserver pools,
+such as &'pool.sks-keyservers.net'&.
+
+At time of last update, releases were being made by Phil Pennock and signed with
+key &'0x403043153903637F'&, although that key is expected to be replaced in 2013.
+A trust path from Nigel's key to Phil's can be observed at
+&url(https://www.security.spodhuis.org/exim-trustpath).
+.wen
+
+The signatures for the tar bundles are in:
.display
&_exim-n.nn.tar.gz.asc_&
&_exim-n.nn.tar.bz2.asc_&
&%verify_recipient%&, which independently control the use of the router for
sender and recipient verification. You can set these options directly if
you want a router to be used for only one type of verification.
+Note that cutthrough delivery is classed as a recipient verification
+for this purpose.
.next
If the &%address_test%& option is set false, the router is skipped when Exim is
run with the &%-bt%& option to test an address routing. This can be helpful
.next
Routers can be designated for use only when verifying an address, as
opposed to routing it for delivery. The &%verify_only%& option controls this.
+Again, cutthrough delibery counts as a verification.
.next
Individual routers can be explicitly skipped when running the routers to
check an address given in the SMTP EXPN command (see the &%expn%& option).
The authorization code can be &"Y"& for yes, &"N"& for no, &"X"& for explicit
authorization required but absent, or &"?"& for unknown.
+.cindex "A+" "in &(dnsdb)& lookup"
+The pseudo-type A+ performs an A6 lookup (if configured) followed by an AAAA
+and then an A lookup. All results are returned; defer processing
+(see below) is handled separately for each lookup. Example:
+.code
+${lookup dnsdb {>; a+=$sender_helo_name}}
+.endd
+
.section "Multiple dnsdb lookups" "SECID67"
In the previous sections, &(dnsdb)& lookups for a single domain are described.
There are several types of pattern that require Exim to know the name of the
remote host. These are either wildcard patterns or lookups by name. (If a
complete hostname is given without any wildcarding, it is used to find an IP
-address to match against, as described in the section &<<SECThoslispatip>>&
+address to match against, as described in section &<<SECThoslispatip>>&
above.)
If the remote host name is not already known when Exim encounters one of these
operator.
If the query contains a reference to &$sender_host_name$&, Exim automatically
-looks up the host name if has not already done so. (See section
+looks up the host name if it has not already done so. (See section
&<<SECThoslispatnam>>& for comments on finding host names.)
Historical note: prior to release 4.30, Exim would always attempt to find a
surrounding the colons is ignored. For example:
.code
aol.com: spammer1 : spammer2 : ^[0-9]+$ :
- spammer3 : spammer4
+ spammer3 : spammer4
.endd
As in all colon-separated lists in Exim, a colon can be included in an item by
doubling.
Any unused are made empty. The variable &$acl_narg$& is set to the number of
arguments. The named ACL (see chapter &<<CHAPACL>>&) is called
and may use the variables; if another acl expansion is used the values
-are overwritten. If the ACL sets
+are restored after it returns. If the ACL sets
a value using a "message =" modifier and returns accept or deny, the value becomes
the result of the expansion.
-If no message was set and the ACL returned accept or deny
-the value is an empty string.
-If the ACL returned defer the result is a forced-fail. Otherwise the expansion fails.
+If no message is set and the ACL returns accept or deny
+the expansion result is an empty string.
+If the ACL returns defer the result is a forced-fail. Otherwise the expansion fails.
.vitem "&*${dlfunc{*&<&'file'&>&*}{*&<&'function'&>&*}{*&<&'arg'&>&*}&&&
Any unused are made empty. The variable &$acl_narg$& is set to the number of
arguments. The named ACL (see chapter &<<CHAPACL>>&) is called
and may use the variables; if another acl expansion is used the values
-are overwritten. If the ACL sets
+are restored after it returns. If the ACL sets
a value using a "message =" modifier the variable $value becomes
the result of the expansion, otherwise it is empty.
If the ACL returns accept the condition is true; if deny, false.
be terminated by colon or white space, because it may contain a wide variety of
characters. Note also that braces must &'not'& be used.
+.vitem &$headers_added$&
+.vindex "&$headers_added$&"
+Within an ACL this variable contains the headers added so far by
+the ACL modifier add_header (section &<<SECTaddheadacl>>&).
+The headers are a newline-separated list.
+
.vitem &$home$&
.vindex "&$home$&"
When the &%check_local_user%& option is set for a router, the user's home
.option accept_8bitmime main boolean true
.cindex "8BITMIME"
.cindex "8-bit characters"
+.cindex "log" "selectors"
+.cindex "log" "8BITMIME"
This option causes Exim to send 8BITMIME in its response to an SMTP
EHLO command, and to accept the BODY= parameter on MAIL commands.
However, though Exim is 8-bit clean, it is not a protocol converter, and it
&url(http://cr.yp.to/smtp/8bitmime.html)
.endd
+To log received 8BITMIME status use
+.code
+log_selector = +8bitmime
+.endd
+
.option acl_not_smtp main string&!! unset
.cindex "&ACL;" "for non-SMTP messages"
.cindex "non-SMTP messages" "ACLs for"
.cindex "EXPN" "with &%verify_only%&"
.oindex "&%-bv%&"
.cindex "router" "used only when verifying"
-If this option is set, the router is used only when verifying an address or
+If this option is set, the router is used only when verifying an address,
+delivering in cutthrough mode or
testing with the &%-bv%& option, not when actually doing a delivery, testing
with the &%-bt%& option, or running the SMTP EXPN command. It can be further
restricted to verifying only senders or recipients by means of
.option verify_recipient routers&!? boolean true
If this option is false, the router is skipped when verifying recipient
-addresses
+addresses,
+delivering in cutthrough mode
or testing recipient verification using &%-bv%&.
See section &<<SECTrouprecon>>& for a list of the order in which preconditions
are evaluated.
.new
.vitem &*control&~=&~cutthrough_delivery*&
.cindex "&ACL;" "cutthrough routing"
+.cindex "cutthrough" "requesting"
This option requests delivery be attempted while the item is being received.
It is usable in the RCPT ACL and valid only for single-recipient mails forwarded
from one SMTP connection to another. If a recipient-verify callout connection is
requested in the same ACL it is held open and used for the data, otherwise one is made
-after the ACL completes.
+after the ACL completes. Note that routers are used in verify mode.
Should the ultimate destination system positively accept or reject the mail,
a corresponding indication is given to the source system and nothing is queued.
any ACL verb, including &%deny%& (though this is potentially useful only in a
RCPT ACL).
-If the data for the &%add_header%& modifier contains one or more newlines that
+Leading and trailing newlines are removed from
+the data for the &%add_header%& modifier; if it then
+contains one or more newlines that
are not followed by a space or a tab, it is assumed to contain multiple header
lines. Each one is checked for valid syntax; &`X-ACL-Warn:`& is added to the
front of any line that is not a valid header line.
are included in the entry that is written to the reject log.
.cindex "header lines" "added; visibility of"
-Header lines are not visible in string expansions until they are added to the
+Header lines are not visible in string expansions
+of message headers
+until they are added to the
message. It follows that header lines defined in the MAIL, RCPT, and predata
ACLs are not visible until the DATA ACL and MIME ACLs are run. Similarly,
header lines that are added by the DATA or MIME ACLs are not visible in those
this, you can use ACL variables, as described in section
&<<SECTaclvariables>>&.
+The list of headers yet to be added is given by the &%$headers_added%& variable.
+
The &%add_header%& modifier acts immediately as it is encountered during the
processing of an ACL. Notice the difference between these two cases:
.display
ceases, but processing of the ACL continues.
If the argument is a named ACL, up to nine space-separated optional values
-can be appended; they appear in $acl_arg1 to $acl_arg9, and $acl_narg is set
-to the count of values. The name and values are expanded separately.
+can be appended; they appear within the called ACL in $acl_arg1 to $acl_arg9,
+and $acl_narg is set to the count of values.
+Previous values of these variables are restored after the call returns.
+The name and values are expanded separately.
If the nested &%acl%& returns &"drop"& and the outer condition denies access,
the connection is dropped. If it returns &"discard"&, the verb must be
.endd
-.vitem &*hosts&~=&~*&<&'&~host&~list'&>
+.vitem &*hosts&~=&~*&<&'host&~list'&>
.cindex "&%hosts%& ACL condition"
.cindex "host" "ACL checking"
.cindex "&ACL;" "testing the client host"
&`<=`& message arrival
&`=>`& normal message delivery
&`->`& additional address in same delivery
+&`>>`& cutthrough message delivery
&`*>`& delivery suppressed by &%-N%&
&`**`& delivery failed; address bounced
&`==`& delivery deferred; temporary problem
down a single SMTP connection, an asterisk follows the IP address in the log
lines for the second and subsequent messages.
+.cindex "delivery" "cutthrough; logging"
+.cindex "cutthrough" "logging"
+When delivery is done in cutthrough mode it is flagged with &`>>`& and the log
+line precedes the reception line, since cutthrough waits for a possible
+rejection from the destination in case it can reject the sourced item.
+
The generation of a reply message by a filter file gets logged as a
&"delivery"& to the addressee, preceded by &">"&.
The list of optional log items is in the following table, with the default
selection marked by asterisks:
.display
+&` 8bitmime `& received 8BITMIME status
&`*acl_warn_skipped `& skipped &%warn%& statement in ACL
&` address_rewrite `& address rewriting
&` all_parents `& all parents in => lines
More details on each of these items follows:
.ilist
+.cindex "8BITMIME"
+.cindex "log" "8BITMIME"
+&%8bitmime%&: This causes Exim to log any 8BITMIME status of received messages,
+which may help in tracking down interoperability issues with ancient MTAs
+that are not 8bit clean. This is added to the &"<="& line, tagged with
+&`M8S=`& and a value of &`0`&, &`7`& or &`8`&, corresponding to "not given",
+&`7BIT`& and &`8BITMIME`& respectively.
+.next
.cindex "&%warn%& ACL verb" "log when skipping"
&%acl_warn_skipped%&: When an ACL &%warn%& statement is skipped because one of
its conditions cannot be evaluated, a log line to this effect is written if