.cindex "dnsdb modifiers"
.cindex "modifiers" "dnsdb"
.cindex "options" "dnsdb"
-Modifiers for &(dnsdb)& lookups are givien by optional keywords,
+Modifiers for &(dnsdb)& lookups are given by optional keywords,
each followed by a comma,
that may appear before the record type.
.cindex "DNS" timeout
Timeout for the dnsdb lookup can be controlled by a retrans modifier.
The form is &"retrans_VAL"& where VAL is an Exim time specification
-(eg &"5s"&).
+(e.g. &"5s"&).
The default value is set by the main configuration option &%dns_retrans%&.
Retries for the dnsdb lookup can be controlled by a retry modifier.
.new
Note that other parts of Exim use a &'string list'& which does not
-support all the complexity availible in
+support all the complexity available in
domain, host, address and local part lists.
.wen
.cindex "&`+ignore_defer`&"
A temporary DNS lookup failure normally causes a defer action (except when
&%dns_again_means_nonexist%& converts it into a permanent error). However,
-host lists can include &`+ignore_defer`& and &`+include_defer`&, analagous to
+host lists can include &`+ignore_defer`& and &`+include_defer`&, analogous to
&`+ignore_unknown`& and &`+include_unknown`&, as described in the previous
section. These options should be used with care, probably only in non-critical
host lists such as whitelists.
.cindex "&%certextract%&" "certificate fields"
.cindex "certificate" "extracting fields"
The <&'certificate'&> must be a variable of type certificate.
-The field name is expanded and used to retrive the relevant field from
+The field name is expanded and used to retrieve the relevant field from
the certificate. Supported fields are:
.display
&`version `&
RDN elements of a single type may be selected by
a modifier of the type label; if so the expansion
result is a list (newline-separated by default).
-The separator may be changed by another modifer of
+The separator may be changed by another modifier of
a right angle-bracket followed immediately by the new separator.
Recognised RDN type labels include "CN", "O", "OU" and "DC".
prefix each list element with a type string and an equals sign.
Elements of only one type may be selected by a modifier
which is one of "dns", "uri" or "mail";
-if so the elenment tags are omitted.
+if so the element tags are omitted.
If not otherwise noted field values are presented in human-readable form.
To clarify "list of addresses in RFC 2822 format" mentioned above, Exim follows
a strict interpretation of header line formatting. Exim parses the bare,
unquoted portion of an email address and if it finds a comma, treats it as an
-email address seperator. For the example header line:
+email address separator. For the example header line:
.code
From: =?iso-8859-2?Q?Last=2C_First?= <user@example.com>
.endd
.vitem &*${reverse_ip:*&<&'ipaddr'&>&*}*&
.cindex "expansion" "IP address"
This operator reverses an IP address; for IPv4 addresses, the result is in
-dotted-quad decimal form, while for IPv6 addreses the result is in
+dotted-quad decimal form, while for IPv6 addresses the result is in
dotted-nibble hexadecimal form. In both cases, this is the "natural" form
for DNS. For example,
.code
&"no"& if the result was not labelled as authenticated data
and &"yes"& if it was.
.new
-Results that are labelled as authoritive answer that match
+Results that are labelled as authoritative answer that match
the &%dns_trust_aa%& configuration variable count also
as authenticated data.
.wen
.vindex "&$sender_helo_dnssec$&"
This boolean variable is true if a successful HELO verification was
.cindex "DNS" "DNSSEC"
-done using DNS information the resolver library stated was authenticatied data.
+done using DNS information the resolver library stated was authenticated data.
.wen
.vitem &$sender_helo_name$&
.endd
Exim does not perform DNSSEC validation itself, instead leaving that to a
-validating resolver (eg, unbound, or bind with suitable configuration).
+validating resolver (e.g. unbound, or bind with suitable configuration).
If you have changed &%host_lookup_order%& so that &`bydns`& is not the first
mechanism in the list, then this variable will be false.
This variable is set to &"1"& if a TLS certificate was verified when the
message was received, and &"0"& otherwise.
-The deprecated &$tls_certificate_verfied$& variable refers to the inbound side
+The deprecated &$tls_certificate_verified$& variable refers to the inbound side
except when used in the context of an outbound SMTP delivery, when it refers to
the outbound.
It appears that more and more DNS zone administrators are breaking the rules
and putting domain names that look like IP addresses on the right hand side of
MX records. Exim follows the rules and rejects this, giving an error message
-that explains the mis-configuration. However, some other MTAs support this
+that explains the misconfiguration. However, some other MTAs support this
practice, so to avoid &"Why can't Exim do this?"& complaints,
&%allow_mx_to_ip%& exists, in order to enable this heinous activity. It is not
recommended, except when you have no other choice.
match with this expanded domain list.
Use this option only if you talk directly to a resolver that is
-authoritive for some zones and does not set the AD (Authentic Data)
+authoritative for some zones and does not set the AD (Authentic Data)
bit in the answer. Some DNS servers may have an configuration option to
mark the answers from their own zones as verified (they set the AD bit).
Others do not have this option. It is considered as poor practice using
-a resolver that is an authoritive server for some zones.
+a resolver that is an authoritative server for some zones.
Use this option only if you really have to (e.g. if you want
to use DANE for remote delivery to a server that is listed in the DNS
-zones that your resolver is authoritive for).
+zones that your resolver is authoritative for).
If the DNS answer packet has the AA bit set and contains resource record
in the answer section, the name of the first NS record appearing in the
authority section is compared against the list. If the answer packet is
-authoritive but the answer section is empty, the name of the first SOA
-record in the authoritive section is used instead.
+authoritative but the answer section is empty, the name of the first SOA
+record in the authoritative section is used instead.
.wen
.cindex "DNS" "resolver options"
Exim's transports have an option for adding an &'Envelope-to:'& header to a
message when it is delivered, in exactly the same way as &'Return-path:'& is
handled. &'Envelope-to:'& records the original recipient address from the
-messages's envelope that caused the delivery to happen. Such headers should not
+message's envelope that caused the delivery to happen. Such headers should not
be present in incoming messages, and this option causes them to be removed at
the time the message is received, to avoid any problems that might occur when a
delivered message is subsequently sent on to some other recipient.
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
+probably safest to just set it to a little larger than this value. E.g., with a
default Exim message size of 50M and a default ClamAV StreamMaxLength of 10M,
some problems may result.
If the option is set, PRDR is advertised by Exim when operating as a server.
If the client requests PRDR, and more than one recipient, for a message
an additional ACL is called for each recipient after the message content
-is recieved. See section &<<SECTPRDRACL>>&.
+is received. See section &<<SECTPRDRACL>>&.
.option preserve_message_logs main boolean false
.cindex "message logs" "preserving"
and will be taken as empty; an explicit location
must be specified.
-The use of a directory for the option value is not avilable for GnuTLS versions
+The use of a directory for the option value is not available for GnuTLS versions
preceding 3.3.6 and a single file must be used.
With OpenSSL the certificates specified
.section "Problems with DNS lookups" "SECTprowitdnsloo"
There have been problems with DNS servers when SRV records are looked up.
-Some mis-behaving servers return a DNS error or timeout when a non-existent
+Some misbehaving servers return a DNS error or timeout when a non-existent
SRV record is sought. Similar problems have in the past been reported for
MX records. The global &%dns_again_means_nonexist%& option can help with this
problem, but it is heavy-handed because it is a global option.
.cindex "black hole"
.cindex "abandoning mail"
&':blackhole:'& 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 specifing
+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.
&*Warning*&: If &':blackhole:'& appears anywhere in a redirection list, no
.cindex "DNS" "DNSSEC"
DNS lookups for domains matching &%dnssec_request_domains%& will be done with
the dnssec request bit set. Any returns not having the Authenticated Data bit
-(AD bit) set wil be ignored and logged as a host-lookup failure.
+(AD bit) set will be ignored and logged as a host-lookup failure.
This applies to all of the SRV, MX, AAAA, A lookup sequence.
deliveries into closed message stores. Exim also has support for running LMTP
over a pipe to a local process &-- see chapter &<<CHAPLMTP>>&.
-If this option is set to &"smtps"&, the default vaule for the &%port%& option
+If this option is set to &"smtps"&, the default value for the &%port%& option
changes to &"smtps"&, and the transport initiates TLS immediately after
connecting, as an outbound SSL-on-connect, instead of using STARTTLS to upgrade.
The Internet standards bodies strongly discourage use of this mode.
is taken as empty and an explicit location
must be specified.
-The use of a directory for the option value is not avilable for GnuTLS versions
+The use of a directory for the option value is not available for GnuTLS versions
preceding 3.3.6 and a single file must be used.
.wen
&$host_address$& are set to the name and address of the server during the
expansion of this option. See chapter &<<CHAPTLS>>& for details of TLS.
-For back-compatability,
+For back-compatibility,
if neither tls_verify_hosts nor tls_try_verify_hosts are set
(a single-colon empty list counts as being set)
and certificate verification fails the TLS connection is closed.
.option client_set_id authenticators string&!! unset
When client authentication succeeds, this condition is expanded; the
-result is used in the log lines for outbound messasges.
+result is used in the log lines for outbound messages.
Typically it will be the user name used for authentication.
.option server_service heimdal_gssapi string&!! "smtp"
This option specifies the service identifier used, in conjunction with
-&%server_hostname%&, for building the identifer for finding credentials
+&%server_hostname%&, for building the identifier for finding credentials
from the keytab.
If an authenticator of this type is configured it is
run before any SMTP-level communication is done,
and can authenticate the connection.
-If it does, SMTP suthentication is not offered.
+If it does, SMTP authentication is not offered.
A maximum of one authenticator of this type may be present.
These may be the system default set (depending on library version),
.wen
a file or,
-depnding on liibrary version, a directory,
+depending on library version, a directory,
must name a file or,
for OpenSSL only (not GnuTLS), a directory.
The client verifies the server's certificate
within and possibly choose to use different certificates and keys (and more)
for this session.
-This is analagous to HTTP's &"Host:"& header, and is the main mechanism by
+This is analogous to HTTP's &"Host:"& header, and is the main mechanism by
which HTTPS-enabled web-sites can be virtual-hosted, many sites to one IP
address.
The Exim developers are proceeding cautiously and so far no other TLS options
are re-expanded.
-When Exim is built againt OpenSSL, OpenSSL must have been built with support
+When Exim is built against OpenSSL, OpenSSL must have been built with support
for TLS Extensions. This holds true for OpenSSL 1.0.0+ and 0.9.8+ with
enable-tlsext in EXTRACONFIGURE. If you invoke &(openssl s_client -h)& and
see &`-servername`& in the output, then OpenSSL has support.
client and server for a message, and more than one recipient
has been accepted.
-The ACL test specfied by &%acl_smtp_data_prdr%& happens after a message
-has been recieved, and is executed once for each recipient of the message
+The ACL test specified by &%acl_smtp_data_prdr%& happens after a message
+has been received, and is executed once for each recipient of the message
with &$local_part$& and &$domain$& valid.
-The test may accept, defer or deny for inividual recipients.
+The test may accept, defer or deny for individual recipients.
The &%acl_smtp_data%& will still be called after this ACL and
can reject the message overall, even if this ACL has accepted it
for some or all recipients.
for this can be disabled when the MAIL-time $smtp_command included
"PRDR". Any required difference in behaviour of the main DATA-time
ACL should however depend on the PRDR-time ACL having run, as Exim
-will avoid doing so in some situations (eg. single-recipient mails).
+will avoid doing so in some situations (e.g. single-recipient mails).
See also the &%prdr_enable%& global option
and the &%hosts_try_prdr%& smtp transport option.
This option requests delivery be attempted while the item is being received.
The option is usable in the RCPT ACL.
-If enabled for a message recieved via smtp and routed to an smtp transport,
+If enabled for a message received via smtp and routed to an smtp transport,
.new
and only one transport, interface, destination host and port combination
is used for all recipients of the message,
If a recipient-verify callout connection is subsequently
requested in the same ACL it is held open and used for
.new
-any subsequent receipients and the data,
+any subsequent recipients and the data,
.wen
otherwise one is made after the initial RCPT ACL completes.
of outgoing messages is done, because it sends data to the ultimate destination
before the entire message has been received from the source.
.new
-It is not supported for messages recieved with the SMTP PRDR option in use.
+It is not supported for messages received with the SMTP PRDR option in use.
.wen
Should the ultimate destination system positively accept or reject the mail,
.vitem &%avast%&
.cindex "virus scanners" "avast"
This is the scanner daemon of Avast. It has been tested with Avast Core
-Security (currenty at version 1.1.7).
+Security (currently at version 1.1.7).
You can get a trial version at &url(http://www.avast.com) or for Linux
at &url(http://www.avast.com/linux-server-antivirus).
This scanner type takes one option,
This is a general-purpose way of talking to simple scanner daemons
running on the local machine.
There are four options:
-an address (which may be an IP addres and port, or the path of a Unix socket),
+an address (which may be an IP address and port, or the path of a Unix socket),
a commandline to send (may include a single %s which will be replaced with
the path to the mail file to be scanned),
an RE to trigger on from the returned data,
The &`pri`& option specifies a priority for the server within the list,
higher values being tried first.
-The deafult priority is 1.
+The default priority is 1.
The &`weight`& option specifies a selection bias.
Within a priority set
characters, may be omitted and will be taken as zero.
Timeout specifications for the &`retry`& and &`tmo`& options
-are the usual Exim time interval standard, eg. &`20s`& or &`1m`&.
+are the usual Exim time interval standard, e.g. &`20s`& or &`1m`&.
The &`tmo`& option specifies an overall timeout for communication.
The default value is two minutes.
are not set.
.new
Careful enforcement of single-recipient messages
-(eg. by responding with defer in the recipient ACL for all recipients
+(e.g. by responding with defer in the recipient ACL for all recipients
after the first),
or the use of PRDR,
.cindex "PRDR" "use for per-user SpamAssassin profiles"
shows that the client issued QUIT straight after EHLO. If there were fewer
than 20 commands, they are all listed. If there were more than 20 commands,
the last 20 are listed, preceded by &"..."&. However, with the default
-setting of 10 for &%smtp_accep_max_nonmail%&, the connection will in any case
+setting of 10 for &%smtp_accept_max_nonmail%&, the connection will in any case
have been aborted before 20 non-mail commands are processed.
.next
&%smtp_mailauth%&: A third subfield with the authenticated sender,
exiqgrep -f '^<>$'
.endd
.vitem &*-r*&&~<&'regex'&>
-Match a recipient address using a case-insensitve search. The field that is
+Match a recipient address using a case-insensitive search. The field that is
tested is not enclosed in angle brackets.
.vitem &*-s*&&~<&'regex'&>
Administrators who use embedded Perl are advised to explore how Perl's
taint checking might apply to their usage.
.next
-Use of &%${expand...}%& is somewhat analagous to shell's eval builtin and
+Use of &%${expand...}%& is somewhat analogous to shell's eval builtin and
administrators are well advised to view its use with suspicion, in case (for
instance) it allows a local-part to contain embedded Exim directives.
.next
&%acl_smtp_dkim%& ACL. 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 acccept, the message is not accepted.
+If any ACL call does not accept, the message is not accepted.
If a cutthrough delivery was in progress for the message it is
summarily dropped (having wasted the transmission effort).
&%pass%&: The signature passed verification. It is valid.
.endlist
.vitem &%$dkim_verify_reason%&
-A string giving a litte bit more detail when &%$dkim_verify_status%& is either
+A string giving a little bit more detail when &%$dkim_verify_status%& is either
"fail" or "invalid". One of
.ilist
&%pubkey_unavailable%& (when &%$dkim_verify_status%&="invalid"): The public
git://git.exim.org / exim.git / commitdiff