-# $Cambridge: exim/src/src/configure.default,v 1.1 2004/10/07 10:39:01 ph10 Exp $
-
######################################################################
# Runtime configuration file for Exim #
######################################################################
######################################################################
# MAIN CONFIGURATION SETTINGS #
######################################################################
+#
# Specify your host's canonical name here. This should normally be the fully
# qualified "official" name of your host. If this option is not set, the
domainlist local_domains = @
domainlist relay_to_domains =
-hostlist relay_from_hosts = 127.0.0.1
+hostlist relay_from_hosts = localhost
+# (We rely upon hostname resolution working for localhost, because the default
+# uncommented configuration needs to work in IPv4-only environments.)
# Most straightforward access control requirements can be obtained by
-# appropriate settings of the above options. In more complicated situations, you
-# may need to modify the Access Control List (ACL) which appears later in this
-# file.
+# appropriate settings of the above options. In more complicated situations,
+# you may need to modify the Access Control Lists (ACLs) which appear later in
+# this file.
# The first setting specifies your local domains, for example:
#
# to any other host on the Internet. Such a setting commonly refers to a
# complete local network as well as the localhost. For example:
#
-# hostlist relay_from_hosts = 127.0.0.1 : 192.168.0.0/16
+# hostlist relay_from_hosts = <; 127.0.0.1 ; ::1 ; 192.168.0.0/16
#
# The "/16" is a bit mask (CIDR notation), not a number of hosts. Note that you
# have to include 127.0.0.1 if you want to allow processes on your host to send
# SMTP mail by using the loopback address. A number of MUAs use this method of
-# sending mail.
-
+# sending mail. Often, connections are made to "localhost", which might be ::1
+# on IPv6-enabled hosts. Do not forget CIDR for your IPv6 networks.
# All three of these lists may contain many different kinds of item, including
# wildcarded names, regular expressions, and file lookups. See the reference
-# manual for details. The lists above are used in the access control list for
-# incoming messages. The name of this ACL is defined here:
+# manual for details. The lists above are used in the access control lists for
+# checking incoming messages. The names of these ACLs are defined here:
acl_smtp_rcpt = acl_check_rcpt
+acl_smtp_data = acl_check_data
+
+# You should not change those settings until you understand how ACLs work.
+
+
+# If you are running a version of Exim that was compiled with the content-
+# scanning extension, you can cause incoming messages to be automatically
+# scanned for viruses. You have to modify the configuration in two places to
+# set this up. The first of them is here, where you define the interface to
+# your scanner. This example is typical for ClamAV; see the manual for details
+# of what to set for other virus scanners. The second modification is in the
+# acl_check_data access control list (see below).
+
+# av_scanner = clamd:/tmp/clamd
+
+
+# For spam scanning, there is a similar option that defines the interface to
+# SpamAssassin. You do not need to set this if you are using the default, which
+# is shown in this commented example. As for virus scanning, you must also
+# modify the acl_check_data access control list to enable spam scanning.
+
+# spamd_address = 127.0.0.1 783
-# You should not change that setting until you understand how ACLs work.
+
+# If Exim is compiled with support for TLS, you may want to enable the
+# following options so that Exim allows clients to make encrypted
+# connections. In the authenticators section below, there are template
+# configurations for plaintext username/password authentication. This kind
+# of authentication is only safe when used within a TLS connection, so the
+# authenticators will only work if the following TLS settings are turned on
+# as well.
+
+# Allow any client to use TLS.
+
+# tls_advertise_hosts = *
+
+# Specify the location of the Exim server's TLS certificate and private key.
+# The private key must not be encrypted (password protected). You can put
+# the certificate and private key in the same file, in which case you only
+# need the first setting, or in separate files, in which case you need both
+# options.
+
+# tls_certificate = /etc/ssl/exim.crt
+# tls_privatekey = /etc/ssl/exim.pem
+
+# For OpenSSL, prefer EC- over RSA-authenticated ciphers
+# tls_require_ciphers = ECDSA:RSA:!COMPLEMENTOFDEFAULT
+
+# In order to support roaming users who wish to send email from anywhere,
+# you may want to make Exim listen on other ports as well as port 25, in
+# case these users need to send email from a network that blocks port 25.
+# The standard port for this purpose is port 587, the "message submission"
+# port. See RFC 4409 for details. Microsoft MUAs cannot be configured to
+# talk the message submission protocol correctly, so if you need to support
+# them you should also allow TLS-on-connect on the traditional but
+# non-standard port 465.
+
+# daemon_smtp_ports = 25 : 465 : 587
+# tls_on_connect_ports = 465
# Specify the domain you want to be added to all unqualified addresses
# allow_domain_literals
-# No deliveries will ever be run under the uids of these users (a colon-
-# separated list). An attempt to do so causes a panic error to be logged, and
-# the delivery to be deferred. This is a paranoic safety catch. There is an
-# even stronger safety catch in the form of the FIXED_NEVER_USERS setting
-# in the configuration for building Exim. The list of users that it specifies
-# is built into the binary, and cannot be changed. The option below just adds
-# additional users to the list. The default for FIXED_NEVER_USERS is "root",
-# but just to be absolutely sure, the default here is also "root".
+# No deliveries will ever be run under the uids of users specified by
+# never_users (a colon-separated list). An attempt to do so causes a panic
+# error to be logged, and the delivery to be deferred. This is a paranoic
+# safety catch. There is an even stronger safety catch in the form of the
+# FIXED_NEVER_USERS setting in the configuration for building Exim. The list of
+# users that it specifies is built into the binary, and cannot be changed. The
+# option below just adds additional users to the list. The default for
+# FIXED_NEVER_USERS is "root", but just to be absolutely sure, the default here
+# is also "root".
# Note that the default setting means you cannot deliver mail addressed to root
# as if it were a normal user. This isn't usually a problem, as most sites have
host_lookup = *
-# The settings below, which are actually the same as the defaults in the
-# code, cause Exim to make RFC 1413 (ident) callbacks for all incoming SMTP
-# calls. You can limit the hosts to which these calls are made, and/or change
-# the timeout that is used. If you set the timeout to zero, all RFC 1413 calls
-# are disabled. RFC 1413 calls are cheap and can provide useful information
-# for tracing problem messages, but some hosts and firewalls have problems
-# with them. This can result in a timeout instead of an immediate refused
-# connection, leading to delays on starting up an SMTP session.
+# The settings below cause Exim to make RFC 1413 (ident) callbacks
+# for all incoming SMTP calls. You can limit the hosts to which these
+# calls are made, and/or change the timeout that is used. If you set
+# the timeout to zero, all RFC 1413 calls are disabled. RFC 1413 calls
+# are cheap and can provide useful information for tracing problem
+# messages, but some hosts and firewalls have problems with them.
+# This can result in a timeout instead of an immediate refused
+# connection, leading to delays on starting up SMTP sessions.
+# (The default was reduced from 30s to 5s for release 4.61. and to
+# disabled for release 4.86)
+#
+#rfc1413_hosts = *
+#rfc1413_query_timeout = 5s
+
-rfc1413_hosts = *
-rfc1413_query_timeout = 30s
+# Enable an efficiency feature. We advertise the feature; clients
+# may request to use it. For multi-recipient mails we then can
+# reject or accept per-user after the message is received.
+#
+prdr_enable = true
# By default, Exim expects all envelope addresses to be fully qualified, that
# and/or qualify_recipient (see above).
+# Unless you run a high-volume site you probably want more logging
+# detail than the default. Adjust to suit.
+
+log_selector = +smtp_protocol_error +smtp_syntax_error \
+ +tls_certificate_verified
+
+
# If you want Exim to support the "percent hack" for certain domains,
# uncomment the following line and provide a list of domains. The "percent
# hack" is the feature by which mail addressed to x%y@z (where z is one of
timeout_frozen_after = 7d
+# By default, messages that are waiting on Exim's queue are all held in a
+# single directory called "input" which it itself within Exim's spool
+# directory. (The default spool directory is specified when Exim is built, and
+# is often /var/spool/exim/.) Exim works best when its queue is kept short, but
+# there are circumstances where this is not always possible. If you uncomment
+# the setting below, messages on the queue are held in 62 subdirectories of
+# "input" instead of all in the same directory. The subdirectories are called
+# 0, 1, ... A, B, ... a, b, ... z. This has two benefits: (1) If your file
+# system degrades with many files in one directory, this is less likely to
+# happen; (2) Exim can process the queue one subdirectory at a time instead of
+# all at once, which can give better performance with large queues.
+
+# split_spool_directory = true
+
+
+# If you're in a part of the world where ASCII is not sufficient for most
+# text, then you're probably familiar with RFC2047 message header extensions.
+# By default, Exim adheres to the specification, including a limit of 76
+# characters to a line, with encoded words fitting within a line.
+# If you wish to use decoded headers in message filters in such a way
+# that successful decoding of malformed messages matters, you may wish to
+# configure Exim to be more lenient.
+#
+# check_rfc2047_length = false
+#
+# In particular, the Exim maintainers have had multiple reports of problems
+# from Russian administrators of issues until they disable this check,
+# because of some popular, yet buggy, mail composition software.
+
+
+# If you wish to be strictly RFC compliant, or if you know you'll be
+# exchanging email with systems that are not 8-bit clean, then you may
+# wish to disable advertising 8BITMIME. Uncomment this option to do so.
+
+# accept_8bitmime = false
+
+
+# Exim does not make use of environment variables itself. However,
+# libraries that Exim uses (e.g. LDAP) depend on specific environment settings.
+# There are two lists: keep_environment for the variables we trust, and
+# add_environment for variables we want to set to a specific value.
+# Note that TZ is handled separately by the timezone runtime option
+# and TIMEZONE_DEFAULT buildtime option.
+
+# keep_environment = ^LDAP
+# add_environment = PATH=/usr/bin::/bin
+
+
######################################################################
# ACL CONFIGURATION #
# testing for an empty sending host field.
accept hosts = :
+ control = dkim_disable_verify
#############################################################################
# The following section of the ACL is concerned with local parts that contain
#
# Two different rules are used. The first one is stricter, and is applied to
# messages that are addressed to one of the local domains handled by this
- # host. It blocks local parts that begin with a dot or contain @ % ! / or |.
- # If you have local accounts that include these characters, you will have to
- # modify this rule.
+ # host. The line "domains = +local_domains" restricts it to domains that are
+ # defined by the "domainlist local_domains" setting above. The rule blocks
+ # local parts that begin with a dot or contain @ % ! / or |. If you have
+ # local accounts that include these characters, you will have to modify this
+ # rule.
deny message = Restricted characters in address
domains = +local_domains
local_parts = ^[.] : ^.*[@%!/|]
- # The second rule applies to all other domains, and is less strict. This
- # allows your own users to send outgoing messages to sites that use slashes
- # and vertical bars in their local parts. It blocks local parts that begin
- # with a dot, slash, or vertical bar, but allows these characters within the
- # local part. However, the sequence /../ is barred. The use of @ % and ! is
- # blocked, as before. The motivation here is to prevent your users (or
- # your users' viruses) from mounting certain kinds of attack on remote sites.
+ # The second rule applies to all other domains, and is less strict. The line
+ # "domains = !+local_domains" restricts it to domains that are NOT defined by
+ # the "domainlist local_domains" setting above. The exclamation mark is a
+ # negating operator. This rule allows your own users to send outgoing
+ # messages to sites that use slashes and vertical bars in their local parts.
+ # It blocks local parts that begin with a dot, slash, or vertical bar, but
+ # allows these characters within the local part. However, the sequence /../
+ # is barred. The use of @ % and ! is blocked, as before. The motivation here
+ # is to prevent your users (or your users' viruses) from mounting certain
+ # kinds of attack on remote sites.
deny message = Restricted characters in address
domains = !+local_domains
require verify = sender
+ # Accept if the message comes from one of the hosts for which we are an
+ # outgoing relay. It is assumed that such hosts are most likely to be MUAs,
+ # so we set control=submission to make Exim treat the message as a
+ # submission. It will fix up various errors in the message, for example, the
+ # lack of a Date: header line. If you are actually relaying out out from
+ # MTAs, you may want to disable this. If you are handling both relaying from
+ # MTAs and submissions from MUAs you should probably split them into two
+ # lists, and handle them differently.
+
+ # Recipient verification is omitted here, because in many cases the clients
+ # are dumb MUAs that don't cope well with SMTP error responses. If you are
+ # actually relaying out from MTAs, you should probably add recipient
+ # verification here.
+
+ # Note that, by putting this test before any DNS black list checks, you will
+ # always accept from these hosts, even if they end up on a black list. The
+ # assumption is that they are your friends, and if they get onto a black
+ # list, it is a mistake.
+
+ accept hosts = +relay_from_hosts
+ control = submission
+ control = dkim_disable_verify
+
+ # Accept if the message arrived over an authenticated connection, from
+ # any host. Again, these messages are usually from MUAs, so recipient
+ # verification is omitted, and submission mode is set. And again, we do this
+ # check before any black list tests.
+
+ accept authenticated = *
+ control = submission
+ control = dkim_disable_verify
+
+ # Insist that a HELO/EHLO was accepted.
+
+ require message = nice hosts say HELO first
+ condition = ${if def:sender_helo_name}
+
+ # Insist that any other recipient address that we accept is either in one of
+ # our local domains, or is in a domain for which we explicitly allow
+ # relaying. Any other domain is rejected as being unacceptable for relaying.
+
+ require message = relay not permitted
+ domains = +local_domains : +relay_to_domains
+
+ # We also require all accepted addresses to be verifiable. This check will
+ # do local part verification for local domains, but only check the domain
+ # for remote domains. The only way to check local parts for the remote
+ # relay domains is to use a callout (add /callout), but please read the
+ # documentation about callouts before doing this.
+
+ require verify = recipient
+
#############################################################################
- # There are no checks on DNS "black" lists because the domains that contain
- # these lists are changing all the time. However, here are two examples of
- # how you could get Exim to perform a DNS black list lookup at this point.
- # The first one denies, while the second just warns.
+ # There are no default checks on DNS black lists because the domains that
+ # contain these lists are changing all the time. However, here are two
+ # examples of how you can get Exim to perform a DNS black list lookup at this
+ # point. The first one denies, whereas the second just warns.
#
# deny message = rejected because $sender_host_address is in a black list at $dnslist_domain\n$dnslist_text
# dnslists = black.list.example
#
- # warn message = X-Warning: $sender_host_address is in a black list at $dnslist_domain
+ # warn dnslists = black.list.example
+ # add_header = X-Warning: $sender_host_address is in a black list at $dnslist_domain
# log_message = found in $dnslist_domain
- # dnslists = black.list.example
#############################################################################
- # Accept if the address is in a local domain, but only if the recipient can
- # be verified. Otherwise deny. The "endpass" line is the border between
- # passing on to the next ACL statement (if tests above it fail) or denying
- # access (if tests below it fail).
+ #############################################################################
+ # This check is commented out because it is recognized that not every
+ # sysadmin will want to do it. If you enable it, the check performs
+ # Client SMTP Authorization (csa) checks on the sending host. These checks
+ # do DNS lookups for SRV records. The CSA proposal is currently (May 2005)
+ # an Internet draft. You can, of course, add additional conditions to this
+ # ACL statement to restrict the CSA checks to certain hosts only.
+ #
+ # require verify = csa
+ #############################################################################
- accept domains = +local_domains
- endpass
- verify = recipient
+ # At this point, the address has passed all the checks that have been
+ # configured, so we accept it unconditionally.
- # Accept if the address is in a domain for which we are relaying, but again,
- # only if the recipient can be verified.
+ accept
- accept domains = +relay_to_domains
- endpass
- verify = recipient
- # If control reaches this point, the domain is neither in +local_domains
- # nor in +relay_to_domains.
+# This ACL is used after the contents of a message have been received. This
+# is the ACL in which you can test a message's headers or body, and in
+# particular, this is where you can invoke external virus or spam scanners.
+# Some suggested ways of configuring these tests are shown below, commented
+# out. Without any tests, this ACL accepts all messages. If you want to use
+# such tests, you must ensure that Exim is compiled with the content-scanning
+# extension (WITH_CONTENT_SCAN=yes in Local/Makefile).
- # Accept if the message comes from one of the hosts for which we are an
- # outgoing relay. Recipient verification is omitted here, because in many
- # cases the clients are dumb MUAs that don't cope well with SMTP error
- # responses. If you are actually relaying out from MTAs, you should probably
- # add recipient verification here.
+acl_check_data:
- accept hosts = +relay_from_hosts
+ # Deny if the message contains an overlong line. Per the standards
+ # we should never receive one such via SMTP.
+ #
+ deny message = maximum allowed line length is 998 octets, \
+ got $max_received_linelength
+ condition = ${if > {$max_received_linelength}{998}}
- # Accept if the message arrived over an authenticated connection, from
- # any host. Again, these messages are usually from MUAs, so recipient
- # verification is omitted.
+ # Deny if the headers contain badly-formed addresses.
+ #
+ deny !verify = header_syntax
+ message = header syntax
+ log_message = header syntax ($acl_verify_message)
- accept authenticated = *
+ # Deny if the message contains a virus. Before enabling this check, you
+ # must install a virus scanner and set the av_scanner option above.
+ #
+ # deny malware = *
+ # message = This message contains a virus ($malware_name).
+
+ # Add headers to a message if it is judged to be spam. Before enabling this,
+ # you must install SpamAssassin. You may also need to set the spamd_address
+ # option above.
+ #
+ # warn spam = nobody
+ # add_header = X-Spam_score: $spam_score\n\
+ # X-Spam_score_int: $spam_score_int\n\
+ # X-Spam_bar: $spam_bar\n\
+ # X-Spam_report: $spam_report
- # Reaching the end of the ACL causes a "deny", but we might as well give
- # an explicit message.
+ # Accept the message.
- deny message = relay not permitted
+ accept
# This router routes addresses that are not in local domains by doing a DNS
-# lookup on the domain name. Any domain that resolves to 0.0.0.0 or to a
-# loopback interface address (127.0.0.0/8) is treated as if it had no DNS
-# entry. Note that 0.0.0.0 is the same as 0.0.0.0/32, which is commonly treated
-# as the local host inside the network stack. It is not 0.0.0.0/0, the default
-# route. If the DNS lookup fails, no further routers are tried because of
-# the no_more setting, and consequently the address is unrouteable.
+# lookup on the domain name. The exclamation mark that appears in "domains = !
+# +local_domains" is a negating operator, that is, it can be read as "not". The
+# recipient's domain must not be one of those defined by "domainlist
+# local_domains" above for this router to be used.
+#
+# If the router is used, any domain that resolves to 0.0.0.0 or to a loopback
+# interface address (127.0.0.0/8) is treated as if it had no DNS entry. Note
+# that 0.0.0.0 is the same as 0.0.0.0/32, which is commonly treated as the
+# local host inside the network stack. It is not 0.0.0.0/0, the default route.
+# If the DNS lookup fails, no further routers are tried because of the no_more
+# setting, and consequently the address is unrouteable.
dnslookup:
driver = dnslookup
domains = ! +local_domains
transport = remote_smtp
ignore_target_hosts = 0.0.0.0 : 127.0.0.0/8
+# if ipv6-enabled then instead use:
+# ignore_target_hosts = <; 0.0.0.0 ; 127.0.0.0/8 ; ::1
no_more
-# The remaining routers handle addresses in the local domain(s).
+# This alternative router can be used when you want to send all mail to a
+# server which handles DNS lookups for you; an ISP will typically run such
+# a server for their customers. If you uncomment "smarthost" then you
+# should comment out "dnslookup" above. Setting a real hostname in route_data
+# wouldn't hurt either.
+
+# smarthost:
+# driver = manualroute
+# domains = ! +local_domains
+# transport = remote_smtp
+# route_data = MAIL.HOSTNAME.FOR.CENTRAL.SERVER.EXAMPLE
+# ignore_target_hosts = <; 0.0.0.0 ; 127.0.0.0/8 ; ::1
+# no_more
+
+
+# The remaining routers handle addresses in the local domain(s), that is those
+# domains that are defined by "domainlist local_domains" above.
# This router handles aliasing using a linearly searched alias file with the
# file starts with the string "# Exim filter" or "# Sieve filter", uncomment
# the "allow_filter" option.
-# If you want this router to treat local parts with suffixes introduced by "-"
-# or "+" characters as if the suffixes did not exist, uncomment the two local_
-# part_suffix options. Then, for example, xxxx-foo@your.domain will be treated
-# in the same way as xxxx@your.domain by this router. You probably want to make
-# the same change to the localuser router.
-
# The no_verify setting means that this router is skipped when Exim is
# verifying addresses. Similarly, no_expn means that this router is skipped if
# Exim is processing an EXPN command.
+# If you want this router to treat local parts with suffixes introduced by "-"
+# or "+" characters as if the suffixes did not exist, uncomment the two local_
+# part_suffix options. Then, for example, xxxx-foo@your.domain will be treated
+# in the same way as xxxx@your.domain by this router. Because this router is
+# not used for verification, if you choose to uncomment those options, then you
+# will *need* to make the same change to the localuser router. (There are
+# other approaches, if this is undesirable, but they add complexity).
+
# The check_ancestor option means that if the forward file generates an
# address that is an ancestor of the current one, the current one gets
# passed on instead. This covers the case where A is aliased to B and B
# This transport is used for delivering messages over SMTP connections.
+# Refuse to send any message with over-long lines, which could have
+# been received other than via SMTP. The use of message_size_limit to
+# enforce this is a red herring.
remote_smtp:
driver = smtp
+ message_size_limit = ${if > {$max_received_linelength}{998} {1}{0}}
# This transport is used for local delivery to user mailboxes in traditional
# hours, then retries every 6 hours until 4 days have passed since the first
# failed delivery.
+# WARNING: If you do not have any retry rules at all (this section of the
+# configuration is non-existent or empty), Exim will not do any retries of
+# messages that fail to get delivered at the first attempt. The effect will
+# be to treat temporary errors as permanent. Therefore, DO NOT remove this
+# retry rule unless you really don't want any retries.
+
# Address or Domain Error Retries
# ----------------- ----- -------
# AUTHENTICATION CONFIGURATION #
######################################################################
-# There are no authenticator specifications in this default configuration file.
+# The following authenticators support plaintext username/password
+# authentication using the standard PLAIN mechanism and the traditional
+# but non-standard LOGIN mechanism, with Exim acting as the server.
+# PLAIN and LOGIN are enough to support most MUA software.
+#
+# These authenticators are not complete: you need to change the
+# server_condition settings to specify how passwords are verified.
+# They are set up to offer authentication to the client only if the
+# connection is encrypted with TLS, so you also need to add support
+# for TLS. See the global configuration options section at the start
+# of this file for more about TLS.
+#
+# The default RCPT ACL checks for successful authentication, and will accept
+# messages from authenticated users from anywhere on the Internet.
begin authenticators
+# PLAIN authentication has no server prompts. The client sends its
+# credentials in one lump, containing an authorization ID (which we do not
+# use), an authentication ID, and a password. The latter two appear as
+# $auth2 and $auth3 in the configuration and should be checked against a
+# valid username and password. In a real configuration you would typically
+# use $auth2 as a lookup key, and compare $auth3 against the result of the
+# lookup, perhaps using the crypteq{}{} condition.
+
+#PLAIN:
+# driver = plaintext
+# server_set_id = $auth2
+# server_prompts = :
+# server_condition = Authentication is not yet configured
+# server_advertise_condition = ${if def:tls_in_cipher }
+
+# LOGIN authentication has traditional prompts and responses. There is no
+# authorization ID in this mechanism, so unlike PLAIN the username and
+# password are $auth1 and $auth2. Apart from that you can use the same
+# server_condition setting for both authenticators.
+
+#LOGIN:
+# driver = plaintext
+# server_set_id = $auth1
+# server_prompts = <| Username: | Password:
+# server_condition = Authentication is not yet configured
+# server_advertise_condition = ${if def:tls_in_cipher }
######################################################################
git://git.exim.org / exim.git / blobdiff