-# $Cambridge: exim/src/src/configure.default,v 1.5 2005/10/11 13:50:48 ph10 Exp $
-
######################################################################
# Runtime configuration file for Exim #
######################################################################
hostlist relay_from_hosts = 127.0.0.1
# 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:
#
# spamd_address = 127.0.0.1 783
+# 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
+
+# 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
# here. An unqualified address is one that does not contain an "@" character
# followed by a domain. For example, "caesar@rome.example" is a fully qualified
# 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
# 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.
+# connection, leading to delays on starting up SMTP sessions. (The default was
+# reduced from 30s to 5s for release 4.61.)
rfc1413_hosts = *
-rfc1413_query_timeout = 30s
+rfc1413_query_timeout = 5s
# By default, Exim expects all envelope addresses to be fully qualified, that
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.
+
######################################################################
# 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
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
accept authenticated = *
control = submission
+ control = dkim_disable_verify
+
+ # 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 default checks on DNS black lists because the domains that
# 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 $dnslist_domain
- # dnslists = black.list.example
#############################################################################
#############################################################################
# require verify = csa
#############################################################################
- # Accept if the address is in a local domain, but only if the recipient can
- # be verified. Otherwise deny. The "endpass" line is the border between
- # passing on to the next ACL statement (if tests above it fail) or denying
- # access (if tests below it fail).
-
- accept domains = +local_domains
- endpass
- verify = recipient
-
- # Accept if the address is in a domain for which we are an incoming relay,
- # but again, only if the recipient can be verified.
-
- accept domains = +relay_to_domains
- endpass
- verify = recipient
+ # At this point, the address has passed all the checks that have been
+ # configured, so we accept it unconditionally.
- # Reaching the end of the ACL causes a "deny", but we might as well give
- # an explicit message.
-
- deny message = relay not permitted
+ accept
# This ACL is used after the contents of a message have been received. This
# Deny if the message contains a virus. Before enabling this check, you
# must install a virus scanner and set the av_scanner option above.
#
- # deny malware = *
- # message = This message contains a virus ($malware_name).
+ # 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
- # message = 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
+ # 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
# Accept the message.
# 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
no_more
-# The remaining routers handle addresses in the local domain(s).
+# 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
# 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_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_cipher }
######################################################################