X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/d5c0d8c9374623620844d539d4810da63e9abca1..f8597898434c2e2f73a66c4161c96db3a5f4137d:/src/src/configure.default diff --git a/src/src/configure.default b/src/src/configure.default index a294dc3e6..d23ca3c66 100644 --- a/src/src/configure.default +++ b/src/src/configure.default @@ -9,7 +9,7 @@ # configuration file. There are many more than are mentioned here. The # manual is in the file doc/spec.txt in the Exim distribution as a plain # ASCII file. Other formats (PostScript, Texinfo, HTML, PDF) are available -# from the Exim ftp sites. The manual is also online at the Exim web sites. +# from the Exim ftp sites. The manual is also online at the Exim website. # This file is divided into several parts, all but the first of which are @@ -37,6 +37,18 @@ +###################################################################### +# MACROS # +###################################################################### +# + +# If you want to use a smarthost instead of sending directly to recipient +# domains, uncomment this macro definition and set a real hostname. +# An appropriately privileged user can then redirect email on the command-line +# in emergencies, via -D. +# +# ROUTER_SMARTHOST=MAIL.HOSTNAME.FOR.CENTRAL.SERVER.EXAMPLE + ###################################################################### # MAIN CONFIGURATION SETTINGS # ###################################################################### @@ -107,8 +119,11 @@ hostlist relay_from_hosts = localhost # 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 +acl_smtp_rcpt = acl_check_rcpt +.ifdef _HAVE_PRDR +acl_smtp_data_prdr = acl_check_prdr +.endif +acl_smtp_data = acl_check_data # You should not change those settings until you understand how ACLs work. @@ -153,6 +168,9 @@ acl_smtp_data = acl_check_data # 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. @@ -222,6 +240,13 @@ never_users = root host_lookup = * +# The setting below causes Exim to try to initialize the system resolver +# library with DNSSEC support. It has no effect if your library lacks +# DNSSEC support. + +dns_dnssec_ok = 1 + + # 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 @@ -240,8 +265,15 @@ host_lookup = * # 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. +# This supports recipient-dependent content filtering; without it +# you have to temp-reject any recipients after the first that have +# incompatible filtering, and do the filtering in the data ACL. +# Even with this enabled, you must support the old style for peers +# not flagging support for PRDR (visible via $prdr_requested). # +.ifdef _HAVE_PRDR prdr_enable = true +.endif # By default, Exim expects all envelope addresses to be fully qualified, that @@ -261,7 +293,7 @@ prdr_enable = true # detail than the default. Adjust to suit. log_selector = +smtp_protocol_error +smtp_syntax_error \ - +tls_certificate_verified + +tls_certificate_verified # If you want Exim to support the "percent hack" for certain domains, @@ -451,8 +483,8 @@ acl_check_rcpt: # Insist that a HELO/EHLO was accepted. - require message = nice hosts say HELO first - condition = ${if def:sender_helo_name} + 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 @@ -494,12 +526,45 @@ acl_check_rcpt: # require verify = csa ############################################################################# + ############################################################################# + # If doing per-user content filtering then recipients with filters different + # to the first recipient must be deferred unless the sender talks PRDR. + # + # defer !condition = $prdr_requested + # condition = ${if > {0}{$receipients_count}} + # condition = ${if !eq {$acl_m_content_filter} \ + # {${lookup PER_RCPT_CONTENT_FILTER}}} + # warn !condition = $prdr_requested + # condition = ${if > {0}{$receipients_count}} + # set acl_m_content_filter = ${lookup PER_RCPT_CONTENT_FILTER} + ############################################################################# + # At this point, the address has passed all the checks that have been # configured, so we accept it unconditionally. accept +# This ACL is used once per recipient, for multi-recipient messages, if +# we advertised PRDR. It can be used to perform receipient-dependent +# header- and body- based filtering and rejections. +# We set a variable to record that PRDR was active used, so that checking +# in the data ACL can be skipped. + +.ifdef _HAVE_PRDR +acl_check_prdr: + warn set acl_m_did_prdr = y +.endif + + ############################################################################# + # do lookup on filtering, with $local_part@$domain, deny on filter match + # + # deny set acl_m_content_filter = ${lookup PER_RCPT_CONTENT_FILTER} + # condition = ... + ############################################################################# + + accept + # 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. @@ -517,6 +582,12 @@ acl_check_data: got $max_received_linelength condition = ${if > {$max_received_linelength}{998}} + # Deny if the headers contain badly-formed addresses. + # + deny !verify = header_syntax + message = header syntax + log_message = header syntax ($acl_verify_message) + # Deny if the message contains a virus. Before enabling this check, you # must install a virus scanner and set the av_scanner option above. # @@ -533,6 +604,19 @@ acl_check_data: # X-Spam_bar: $spam_bar\n\ # X-Spam_report: $spam_report + ############################################################################# + # No more tests if PRDR was actively used. + # accept condition = ${if def:acl_m_did_prdr} + # + # To get here, all message recipients must have identical per-user + # content filtering (enforced by RCPT ACL). Do lookup for filter + # and deny on match. + # + # deny set acl_m_content_filter = ${lookup PER_RCPT_CONTENT_FILTER} + # condition = ... + ############################################################################# + + # Accept the message. accept @@ -564,6 +648,25 @@ begin routers # transport = remote_smtp +# This 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. The hostname in route_data comes from the +# macro defined at the top of the file. If not defined, then we'll use the +# dnslookup router below instead. +# Beware that the hostname is specified again in the Transport. + +.ifdef ROUTER_SMARTHOST + +smarthost: + driver = manualroute + domains = ! +local_domains + transport = smarthost_smtp + route_data = ROUTER_SMARTHOST + ignore_target_hosts = <; 0.0.0.0 ; 127.0.0.0/8 ; ::1 + no_more + +.else + # This router routes addresses that are not in local domains by doing a DNS # 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 @@ -586,20 +689,9 @@ dnslookup: # ignore_target_hosts = <; 0.0.0.0 ; 127.0.0.0/8 ; ::1 no_more - -# 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 +# This closes the ROUTER_SMARTHOST ifdef around the choice of routing for +# off-site mail. +.endif # The remaining routers handle addresses in the local domain(s), that is those @@ -716,6 +808,50 @@ begin transports remote_smtp: driver = smtp message_size_limit = ${if > {$max_received_linelength}{998} {1}{0}} +.ifdef _HAVE_PRDR + hosts_try_prdr = * +.endif + + +# This transport is used for delivering messages to a smarthost, if the +# smarthost router is enabled. This starts from the same basis as +# "remote_smtp" but then turns on various security options, because +# we assume that if you're told "use smarthost.example.org as the smarthost" +# then there will be TLS available, with a verifiable certificate for that +# hostname, using decent TLS. + +smarthost_smtp: + driver = smtp + message_size_limit = ${if > {$max_received_linelength}{998} {1}{0}} + multi_domain + # +.ifdef _HAVE_TLS + # Comment out any of these which you have to, then file a Support + # request with your smarthost provider to get things fixed: + hosts_require_tls = * + tls_verify_hosts = * + # As long as tls_verify_hosts is enabled, this won't matter, but if you + # have to comment it out then this will at least log whether you succeed + # or not: + tls_try_verify_hosts = * + # + # The SNI name should match the name which we'll expect to verify; + # many mail systems don't use SNI and this doesn't matter, but if it does, + # we need to send a name which the remote site will recognize. + # This _should_ be the name which the smarthost operators specified as + # the hostname for sending your mail to. + tls_sni = ROUTER_SMARTHOST + # +.ifdef _HAVE_OPENSSL + tls_require_ciphers = HIGH:!aNULL:@STRENGTH +.endif +.ifdef _HAVE_GNUTLS + tls_require_ciphers = SECURE192:-VERS-SSL3.0:-VERS-TLS1.0:-VERS-TLS1.1 +.endif +.endif +.ifdef _HAVE_PRDR + hosts_try_prdr = * +.endif # This transport is used for local delivery to user mailboxes in traditional