/etc/exim4/exim4.conf

##########################################################################
SPAMASSASSIN = yes
SPAM_SCORE = 50
CLAMD =  yes
##########################################################################
 
domainlist local_domains = dsearch;/etc/exim4/domains/
domainlist relay_to_domains = dsearch;/etc/exim4/domains/
hostlist   relay_from_hosts = 127.0.0.1
hostlist   whitelist = net-iplsearch;/etc/exim4/white-blocks.conf
hostlist   spammers = net-iplsearch;/etc/exim4/spam-blocks.conf
no_local_from_check
untrusted_set_sender = *
acl_smtp_connect = acl_check_spammers
acl_smtp_mail = acl_check_mail
acl_smtp_rcpt = acl_check_rcpt
acl_smtp_data = acl_check_data
acl_smtp_mime = acl_check_mime
 
.ifdef SPAMASSASSIN
spamd_address = 127.0.0.1 783
.endif
 
.ifdef CLAMD
av_scanner = clamd: /var/run/clamav/clamd.ctl
.endif
 
tls_advertise_hosts = *
tls_certificate = /usr/local/ssl/certificate.crt
tls_privatekey = /usr/local/ssl/certificate.key
 
daemon_smtp_ports = 25 : 465 : 587 : 2525
tls_on_connect_ports = 465
never_users = root
host_lookup = *
rfc1413_hosts = *
rfc1413_query_timeout = 5s
ignore_bounce_errors_after = 2d
timeout_frozen_after = 7d
 
DKIM_DOMAIN = ${lc:${domain:$h_from:}}
DKIM_FILE = /etc/exim4/domains/${lc:${domain:$h_from:}}/dkim.pem
DKIM_PRIVATE_KEY = ${if exists{DKIM_FILE}{DKIM_FILE}{0}}
 
 
##########################################################################
begin acl
##########################################################################
acl_check_spammers:
  accept hosts = +whitelist
  drop    message       = Your host in blacklist on this server.
          log_message   = Host in blacklist
          hosts         = +spammers
  deny    message       = rejected because $sender_host_address is in a black list at $dnslist_domain\\n$dnslist_text
          dnslists      = ${readfile {/etc/exim4/dnsbl.conf}{:}}
  accept
 
acl_check_mail:
  deny
          condition     = ${if eq{$sender_helo_name}{}}
          message       = HELO required before MAIL
#  drop
#          condition     = ${if isip{$sender_helo_name}}
#          message       = Access denied - Invalid HELO name (See RFC2821 4.1.3)
  drop    message       = Helo name contains a ip address (HELO was $sender_helo_name) and not is valid
          condition     = ${if match{$sender_helo_name}{\N((\d{1,3}[.-]\d{1,3}[.-]\d{1,3}[.-]\d{1,3})|([0-9a-f]{8})|([0-9A-F]{8}))\N}{yes}{no}}
          condition     = ${if match {${lookup dnsdb{>: defer_never,ptr=$sender_host_address}}\}{$sender_helo_name}{no}{yes}}
          delay         = 45s
#  drop
#          condition     = ${if match{$sender_helo_name}{\N^\[\N}{no}{yes}}
#          condition     = ${if match{$sender_helo_name}{\N\.\N}{no}{yes}}
#          message       = Access denied - Invalid HELO name (See RFC2821 4.1.1.1)
  drop
          condition     = ${if isip{$sender_helo_name}}
          message       = Access denied - Invalid HELO name (See RFC2821 4.1.3)
#  drop
#          condition     = ${if match{$sender_helo_name}{\N\.$\N}}
#          message       = Access denied - Invalid HELO name (See RFC2821 4.1.1.1)
#  drop    message       = "REJECTED - Bad HELO - Host impersonating [$sender_helo_name]"
#          condition     = ${if match{$sender_helo_name}{$primary_hostname}}
  drop    condition     = ${if eq{[$interface_address]}{$sender_helo_name}}
          message       = $interface_address is _my_ address
  accept
 
 
acl_check_rcpt:
  accept  hosts         = :
 
  deny    message       = Restricted characters in address
          domains       = +local_domains
          local_parts   = ^[.] : ^.*[@%!/|]
 
  deny    message       = Restricted characters in address
          domains       = !+local_domains
          local_parts   = ^[./|] : ^.*[@%!] : ^.*/\\.\\./
 
  require verify        = sender
 
  accept  hosts         = +relay_from_hosts
          control       = submission
 
  accept  authenticated = *
          control       = submission/domain=
 
  require message       = relay not permitted
          domains       = +local_domains : +relay_to_domains
 
  deny    message       = smtp auth requried
         sender_domains = +local_domains
         !authenticated = *
 
  require verify        = recipient
 
.ifdef CLAMD
  warn    set acl_m0    = no
  warn    condition     = ${if exists {/etc/exim4/domains/$domain/antivirus}{yes}{no}}
          set acl_m0    = yes
.endif
.ifdef SPAMASSASSIN
  warn    set acl_m1    = no
  warn    condition     = ${if exists {/etc/exim4/domains/$domain/antispam}{yes}{no}}
          set acl_m1    = yes
.endif
  accept
 
 
acl_check_data:
.ifdef CLAMD
         deny message   = Message contains a virus ($malware_name) and has been rejected
         malware        = *
         condition      = ${if eq{$acl_m0}{yes}{yes}{no}}
.endif
 
.ifdef SPAMASSASSIN
  warn
         !authenticated = *
         hosts          = !+relay_from_hosts
         condition      = ${if < {$message_size}{100K}}
         condition      = ${if eq{$acl_m1}{yes}{yes}{no}}
         spam           = spamd:true/defer_ok
         add_header     = X-Spam-Score: $spam_score_int
         add_header     = X-Spam-Bar: $spam_bar
         add_header     = X-Spam-Report: $spam_report
         set acl_m2     = $spam_score_int
  warn
         condition      = ${if !eq{$acl_m2}{} {yes}{no}}
         condition      = ${if >{$acl_m2}{SPAM_SCORE} {yes}{no}}
         add_header     = X-Spam-Status: Yes
         message        = SpamAssassin detected spam (from $sender_address to $recipients).
.endif
  accept
 
 
acl_check_mime:
  deny   message       = Blacklisted file extension detected
         condition     = ${if match {${lc:$mime_filename}}{\N(\.ade|\.adp|\.bat|\.chm|\.cmd|\.com|\.cpl|\.exe|\.hta|\.ins|\.isp|\.jse|\.lib|\.lnk|\.mde|\.msc|\.msp|\.mst|\.pif|\.scr|\.sct|\.shb|\.sys|\.vb|\.vbe|\.vbs|\.vxd|\.wsc|\.wsf|\.wsh)$\N}{1}{0}}
  accept
 
##########################################################################
begin authenticators
##########################################################################
dovecot_plain:
  driver = dovecot
  public_name = PLAIN
  server_socket = /var/run/dovecot/auth-client
  server_set_id = $auth1
 
dovecot_login:
  driver = dovecot
  public_name = LOGIN
  server_socket = /var/run/dovecot/auth-client
  server_set_id = $auth1
 
##########################################################################
begin routers
##########################################################################
 
# This is optional.
# It is strictly significant that this router is placed before the dnslookup and all the magic has been done before message could be sent to the outer space. 
# It uses the acl_m2 variable, which was set above is spam was detected to hold the spam_score_int.
# This router checks the acl_m2 variable and recipient's address and if they both are "bad" - simply drops the message to the blackhole.
# The a@domain.com part is just a placeholder for the real email address you want to redirect clean messages to.
# This solution works ONLY with explicitly defined email address while all others are stay intact and be processed as usual.
nospam:
        driver          = accept
        condition       = ${if eq{$local_part@$domain}{a@domain.com}}
        condition       = ${if >{$acl_m2}{SPAM_SCORE}}
        transport       = devnull
 
# This is optional.
# It is strictly significant that this router is placed before the dnslookup and all the magic has been done before message could be sent to 
the outer space. 
# This router will redirect message to gmail instead of original destination.
# The unseen verb is added, to allow the original message to also be processed and delivered to the original destination - i.e. to the local maildir where it will be accessible via roundcube.
# The a@domain.com part is just a placeholder for the real email address you want to redirect clean messages to.
# The @gmail.com part  is just placeholder for the real email you want to redirect clean messages to.
#  This solution works ONLY with explicitly defined email address while all others are stay intact and be processed as usual.
go2gmail:
        driver          = redirect
        condition       = ${if eq{$local_part@$domain}{a@domain.com}}
        data            = a@gmail.com   
        pipe_transport  = address_pipe
        unseen
 
dnslookup:
  driver = dnslookup
  domains = !+local_domains
  transport = remote_smtp
  no_more
 
userforward:
  errors_to =
  driver = redirect
  check_local_user
  file = $home/.forward
  allow_filter
  no_verify
  no_expn
  check_ancestor
  file_transport = address_file
  pipe_transport = address_pipe
  reply_transport = address_reply
 
procmail:
  driver = accept
  check_local_user
  require_files = ${local_part}:+${home}/.procmailrc:/usr/bin/procmail
  transport = procmail
  no_verify
 
autoreplay:
  driver = accept
  require_files = /etc/exim4/domains/$domain/autoreply.${local_part}.msg
  condition = ${if exists{/etc/exim4/domains/$domain/autoreply.${local_part}.msg}}{yes}{no}}
  retry_use_local_part
  transport = userautoreply
  unseen
 
aliases:
  errors_to =
  driver = redirect
  headers_add = X-redirected: yes
  data = ${extract{1}{:}{${lookup{$local_part@$domain}lsearch{/etc/exim4/domains/$domain/aliases}}}}
  require_files = /etc/exim4/domains/$domain/aliases
  redirect_router = dnslookup
  pipe_transport = address_pipe
  unseen
 
localuser_fwd_only:
  driver = accept
  transport = devnull
  condition = ${if exists{/etc/exim/domains/$domain/fwd_only}{${lookup{$local_part}lsearch{/etc/exim/domains/$domain/fwd_only}{true}{false}}}}
 
localuser_spam:
  driver = accept
  transport = local_spam_delivery
  condition = ${if eq {${if match{$h_X-Spam-Status:}{\N^Yes\N}{yes}{no}}} {${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}{yes}{no_such_user}}}}
 
localuser:
  driver = accept
  transport = local_delivery
  condition = ${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}{true}{false}}
 
catchall:
  driver = redirect
  headers_add = X-redirected: yes
  require_files = /etc/exim4/domains/$domain/aliases
  data = ${extract{1}{:}{${lookup{*@$domain}lsearch{/etc/exim4/domains/$domain/aliases}}}}
  file_transport = local_delivery
  redirect_router = dnslookup
 
terminate_alias:
  driver = accept
  transport = devnull
  condition = ${lookup{$local_part@$domain}lsearch{/etc/exim4/domains/$domain/aliases}{true}{false}}
 
 
##########################################################################
begin transports
##########################################################################
remote_smtp:
  driver = smtp
  #helo_data = $sender_address_domain
  dkim_domain = DKIM_DOMAIN
  dkim_selector = mail
  dkim_private_key = DKIM_PRIVATE_KEY
  dkim_canon = relaxed
  dkim_strict = 0
 
 
procmail:
  driver = pipe
  command = "/usr/bin/procmail -d $local_part"
  return_path_add
  delivery_date_add
  envelope_to_add
  user = $local_part
  initgroups
  return_output
 
local_delivery:
  driver = appendfile
  maildir_format
  maildir_use_size_file
  user = ${extract{2}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}
  group = mail
  create_directory
  directory_mode = 770
  mode = 660
  use_lockfile = no
  delivery_date_add
  envelope_to_add
  return_path_add
  directory = "${extract{5}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}/mail/$domain/$local_part"
  quota = ${extract{6}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}M
  quota_warn_threshold = 75%
 
local_spam_delivery:
  driver = appendfile
  maildir_format
  maildir_use_size_file
  user = ${extract{2}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}
  group = mail
  create_directory
  directory_mode = 770
  mode = 660
  use_lockfile = no
  delivery_date_add
  envelope_to_add
  return_path_add
  directory = "${extract{5}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}/mail/$domain/$local_part/.Junk"
  quota = ${extract{6}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}M
  quota_directory = "${extract{5}{:}{${lookup{$local_part}lsearch{/etc/exim4/domains/$domain/passwd}}}}/mail/$domain/$local_part"
  quota_warn_threshold = 75%
 
address_pipe:
  driver = pipe
  return_output
 
address_file:
  driver = appendfile
  delivery_date_add
  envelope_to_add
  return_path_add
 
address_reply:
  driver = autoreply
 
userautoreply:
  driver = autoreply
  file = /etc/exim4/domains/$domain/autoreply.${local_part}.msg
  from = "${local_part}@${domain}"
  subject = "${if def:h_Subject: {Autoreply: ${quote:${escape:$h_Subject:}}} {Autoreply Message}}"
  to = "${sender_address}"
 
devnull:
  driver = appendfile
  file = /dev/null
 
##########################################################################
begin retry
*                      *           F,2h,15m; G,16h,1h,1.5; F,4d,6h
##########################################################################
begin rewrite

The spamassassin configuration is:

# This is the right place to customize your installation of SpamAssassin.
#
# See 'perldoc Mail::SpamAssassin::Conf' for details of what can be
# tweaked.
#
# Only a small subset of options are listed below
#
###########################################################################

#   Add *****SPAM***** to the Subject header of spam e-mails
#
# rewrite_header Subject *****SPAM*****


#   Save spam messages as a message/rfc822 MIME attachment instead of
#   modifying the original message (0: off, 2: use text/plain instead)
#
 report_safe 0
 clear_report_template
 report_contact abuse@domain.com 
 report host: _HOSTNAME_ | contact: _CONTACTADDRESS_ | scores: _TESTSSCORES(,)_ | autolearn=_AUTOLEARN_, score=_AUTOLEARNSCORE_

#   Set which networks or hosts are considered 'trusted' by your mail
#   server (i.e. not spammers)
#
# trusted_networks 212.17.35.


#   Set file-locking method (flock is not safe over NFS, but is faster)
#
# lock_method flock


#   Set the threshold at which a message is considered spam (default: 5.0)
#
 required_score 5.0


#   Use Bayesian classifier (default: 1)
#
 use_bayes 1


#   Bayesian classifier auto-learning (default: 1)
#
 bayes_auto_learn 1


#   Set headers which may provide inappropriate cues to the Bayesian
#   classifier
#
 bayes_ignore_header X-Bogosity
 bayes_ignore_header X-Spam-Flag
 bayes_ignore_header X-Spam-Status
 bayes_ignore_header X-Spam-Report

#   Some shortcircuiting, if the plugin is enabled
# 
ifplugin Mail::SpamAssassin::Plugin::Shortcircuit
#
#   default: strongly-whitelisted mails are *really* whitelisted now, if the
#   shortcircuiting plugin is active, causing early exit to save CPU load.
#   Uncomment to turn this on
#
# shortcircuit USER_IN_WHITELIST       on
# shortcircuit USER_IN_DEF_WHITELIST   on
# shortcircuit USER_IN_ALL_SPAM_TO     on
# shortcircuit SUBJECT_IN_WHITELIST    on

#   the opposite; blacklisted mails can also save CPU
#
# shortcircuit USER_IN_BLACKLIST       on
# shortcircuit USER_IN_BLACKLIST_TO    on
# shortcircuit SUBJECT_IN_BLACKLIST    on

#   if you have taken the time to correctly specify your "trusted_networks",
#   this is another good way to save CPU
#
# shortcircuit ALL_TRUSTED             on

#   and a well-trained bayes DB can save running rules, too
#
# shortcircuit BAYES_99                spam
# shortcircuit BAYES_00                ham

endif # Mail::SpamAssassin::Plugin::Shortcircuit