Add email - Dovecot, rspamd, exim4.

And appropriate configuration for various email domains.

pillar/secrets/dkim.sls.sample

@@ -0,0 +1,25 @@
+dkim:
+  dkim_bear-cave: |
+    -----BEGIN OPENSSH PRIVATE KEY-----
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
+    CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
+    DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
+    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE==
+    -----END OPENSSH PRIVATE KEY-----
+  dkim_cryhavoc: |
+    -----BEGIN OPENSSH PRIVATE KEY-----
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
+    CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
+    DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
+    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE==
+    -----END OPENSSH PRIVATE KEY-----
+  dkim_lunch: |
+    -----BEGIN OPENSSH PRIVATE KEY-----
+    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
+    BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
+    CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
+    DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
+    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE==
+    -----END OPENSSH PRIVATE KEY-----

pillar/top.sls

@@ -4,6 +4,7 @@ base:
     - secrets/mariadb
     - secrets/wordpress
   'scabbers.lunch.org.uk':
+    - secrets/dkim
     - secrets/dnsapi
     - secrets/gitea
     - secrets/webmail

states/debian/init.sls

@@ -1,3 +1,9 @@
+bullseye_backports:
+  pkgrepo.managed:
+    - name: deb http://deb.debian.org/debian bullseye-backports main
+    - dist: bullseye-backports
+    - file: /etc/apt/sources.list.d/bullseye-backports.list
+
 deploy_sshd_config:
   file.managed:
     - name: /etc/ssh/sshd_config

states/email/dovecot.sls

@@ -0,0 +1,29 @@
+dovecot:
+  pkg.installed:
+    - pkgs:
+      - dovecot-core
+      - dovecot-imapd
+      - dovecot-sieve
+      - dovecot-managesieved
+
+dovecot_certs_group:
+  group.present:
+    - name: ssl-cert
+    - system: true
+    - addusers:
+      - dovecot
+
+dovecot_conf:
+  file.managed:
+    - mode: 0644
+    - names:
+      - /etc/dovecot/local.conf:
+        - source: salt://email/dovecot_local.conf
+
+dovecot_service:
+  service.running:
+    - name: dovecot
+    - enable: true
+    - watch:
+      - pkg: dovecot
+      - file: /etc/dovecot/local.conf

states/email/dovecot_local.conf

@@ -0,0 +1,20 @@
+# We use Maildir.
+mail_location = maildir:~/Maildir
+
+# Require SSL for all auth.
+ssl = required
+
+# SSL certificate locations.
+ssl_cert = </var/local/certificates/mail.lunch.org.uk/fullchain.pem
+ssl_key = </var/local/certificates/mail.lunch.org.uk/privkey.pem
+
+# Plugins.
+protocol lda {
+  mail_plugins = acl sieve
+}
+
+# IMAP - increase number of connections per IP.
+protocol imap {
+  mail_max_userip_connections = 40
+}
+

states/email/exim4.sls

@@ -0,0 +1,57 @@
+exim4:
+  pkg.installed:
+    - name: exim4-daemon-heavy
+
+exim4_conf:
+  file.recurse:
+    - name: /etc/exim4
+    - dir_mode: '0755'
+    - file_mode: '0644'
+    - source: salt://email/exim4
+
+# To read system certificate details, you must be in ssl-cert.
+exim4_certs_group:
+  group.present:
+    - name: ssl-cert
+    - system: true
+    - addusers:
+      - Debian-exim
+
+# To deliver using the Dovecot LDA without getting a perms
+# error on /run/dovecot/stats-writer, the Exim user must be in
+# the dovecot group.
+exim4_dovecot_group:
+  group.present:
+    - name: dovecot
+    - system: true
+    - addusers:
+      - Debian-exim
+
+exim4_dkim_private_keys:
+  file.managed:
+    - mode: 0640
+    - group: Debian-exim
+    - names:
+      - /etc/exim4/dkim/bear-cave.org.uk-private.pem:
+        - contents_pillar: dkim:dkim_bear-cave
+      - /etc/exim4/dkim/cryhavoc.org.uk-private.pem:
+        - contents_pillar: dkim:dkim_cryhavoc
+      - /etc/exim4/dkim/lunch.org.uk-private.pem:
+        - contents_pillar: dkim:dkim_lunch
+
+exim4_update_conf:
+  cmd.run:
+    - name: update-exim4.conf
+    - onchanges:
+      - file: exim4_conf
+
+enable_exim4_service:
+  service.enabled:
+    - name: exim4
+
+exim4_service:
+  service.running:
+    - name: exim4
+    - reload: true
+    - watch:
+      - cmd: exim4_update_conf

states/email/exim4/conf.d/acl/10_auth_check

@@ -0,0 +1,7 @@
+# AUTH acl check.
+check_auth:
+  accept  hosts = *
+          endpass
+          message = STARTTLS required before AUTH
+          encrypted = *
+

states/email/exim4/conf.d/auth/30_dovecot_auth

@@ -0,0 +1,18 @@
+# Authenticate via dovecot.
+#
+# For plain and login the connection must be ciphered.
+
+dovecot_plain:
+  driver = dovecot
+  public_name = PLAIN
+  server_socket = /var/run/dovecot/auth-client
+  #server_set_id = $auth2
+  server_mail_auth_condition = false
+
+
+#dovecot_login:
+#  driver = dovecot
+#  public_name = LOGIN
+#  server_socket = /var/run/dovecot/auth-client
+#  #server_set_id = $auth2
+#  server_mail_auth_condition = false

states/email/exim4/conf.d/main/00_localmacros

@@ -0,0 +1,33 @@
+# Trusted users and groups
+MAIN_TRUSTED_USERS=mail:www-data
+
+# User account UID range
+FIRST_USER_ACCOUNT_UID=1000
+
+# TLS configuration
+MAIN_TLS_ENABLE=true
+MAIN_TLS_CERTIFICATE=/var/local/certificates/mail.lunch.org.uk/fullchain.pem
+MAIN_TLS_PRIVATEKEY=/var/local/certificates/mail.lunch.org.uk/privkey.pem
+
+# Local settings
+# CHECK_RCPT_LOCAL_ACL_FILE=/etc/exim4/local_check_rcpt
+CHECK_DATA_LOCAL_ACL_FILE=/etc/exim4/local_check_data
+
+# DKIM keys and handling.
+DKIM_CANON = relaxed
+DKIM_SELECTOR = 20160621
+
+# Get the domain from the outgoing mail.
+DKIM_DOMAIN = ${lc:${domain:$h_from:}}
+
+# The private key file.
+DKIM_FILE = ${lookup {DKIM_DOMAIN-private.pem} dsearch,ret=full,filter=file {/etc/exim4/dkim}}
+
+# If key exists then use it, if not don't.
+DKIM_PRIVATE_KEY = ${if exists{DKIM_FILE} {DKIM_FILE} {0}}
+
+# Log more TLS info than default.
+MAIN_LOG_SELECTOR = +tls_peerdn +tls_sni
+
+# SRS
+SRS_SECRET = sxN7DlwZMWHar1J;L!wlKwbzc9ECB[F>!LEYm9[LF0

states/email/exim4/conf.d/main/20_localconfig

@@ -0,0 +1,13 @@
+# Use rspamd as spam scanner.
+spamd_address = 127.0.0.1 11333 variant=rspamd
+
+# Timeout for virus and spam scans
+local_scan_timeout = 4m
+
+# Allow all users to see mail queue
+no_queue_list_requires_admin
+
+# Listen in ports 25, 465 and 587.
+daemon_smtp_ports = smtp : submission : submissions
+tls_on_connect_ports = submissions
+

states/email/exim4/conf.d/router/180_srs

@@ -0,0 +1,24 @@
+  outbound:
+    driver =    dnslookup
+    # if outbound, and forwarding has been done, use an alternate transport
+    domains =   ! +local_domains
+    transport = ${if eq {$local_part@$domain} \
+                        {$original_local_part@$original_domain} \
+                     {remote_smtp} {remote_forwarded_smtp}}
+
+  inbound_srs:
+    driver =    redirect
+    senders =   :
+    domains =   +local_domains
+    # detect inbound bounces which are SRS'd, and decode them
+    condition = ${if inbound_srs {$local_part} {SRS_SECRET}}
+    data =      $srs_recipient
+
+  inbound_srs_failure:
+    driver =    redirect
+    senders =   :
+    domains =   +local_domains
+    # detect inbound bounces which look SRS'd but are invalid
+    condition = ${if inbound_srs {$local_part} {}}
+    allow_fail
+    data =      :fail: Invalid SRS recipient address

states/email/exim4/conf.d/router/390_throwaway_local_part

@@ -0,0 +1,12 @@
+# Allow a throwaway suffix to the local part. Might help spot who sells
+# email addresses.
+suffix_rewrite:
+  driver = redirect
+  allow_defer
+  allow_fail
+  data = ${local_part}@${domain}
+  local_part_suffix = "_*"
+  local_part_suffix_optional
+  qualify_preserve_domain
+  retry_use_local_part
+

states/email/exim4/conf.d/router/980_local_domain_aliases

@@ -0,0 +1,35 @@
+
+# cryhavoc.org.uk has its own aliases. These are separate to the system
+# ones - see system_aliases.
+cryhavoc_aliases: 
+  driver = redirect
+  allow_defer
+  allow_fail
+  data = ${lookup{$local_part}lsearch{/etc/aliases.cryhavoc.org.uk}}
+  domains = cryhavoc.org.uk
+  qualify_preserve_domain
+  pipe_transport = address_pipe
+  no_more
+
+# cowboybuilder.org.uk has its own aliases. These are separate to the system
+# ones - see system_aliases.
+cowboybuilder_aliases: 
+  driver = redirect
+  allow_defer
+  allow_fail
+  data = ${lookup{$local_part}lsearch{/etc/aliases.cowboybuilder.org.uk}}
+  domains = cowboybuilder.org.uk
+  qualify_preserve_domain
+  pipe_transport = address_pipe
+  no_more
+
+# lunch.org.uk has its own aliases. These are separate to the system
+# ones - see system_aliases.
+lunch_aliases:
+  driver = redirect
+  allow_defer
+  allow_fail
+  data = ${lookup{$local_part}lsearch{/etc/aliases.lunch.org.uk}}
+  domains = lunch.org.uk
+  qualify_preserve_domain
+  retry_use_local_part

states/email/exim4/conf.d/transport/30_dovecot_home

@@ -0,0 +1,16 @@
+
+# Use this to deliver to system users.
+# Exim runs this as the user from the local_user router.
+dovecot_home:
+  debug_print = "T: dovecot_home for $local_part@$domain"
+  driver = pipe
+  #command = sh -c "/usr/bin/bogofilter -e -u -p | /usr/lib/dovecot/deliver"
+  command = /usr/lib/dovecot/deliver
+  message_prefix =
+  message_suffix =
+  log_output
+  delivery_date_add
+  envelope_to_add
+  return_path_add
+  temp_errors = 64 : 69 : 70: 71 : 72 : 73 : 74 : 75 : 78
+

states/email/exim4/conf.d/transport/32_srs

@@ -0,0 +1,7 @@
+  # transport; should look like the non-forward outbound
+  # one, plus the max_rcpt and return_path options
+  remote_forwarded_smtp:
+    driver =              smtp
+    # modify the envelope from, for mails that we forward
+    max_rcpt =            1
+    return_path =         ${srs_encode {SRS_SECRET} {$return_path} {$original_domain}}

states/email/exim4/dkim/20160621.bear-cave.org.uk.pem.txt

@@ -0,0 +1 @@
+k=rsa;p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC97rpW4HWK3q4TIjQnWO6WQZxa1EPPRCJJp3yYcjej8ierPPA420RWm3hyUbfPvwN9ynUXPVfrYYj7FJWMR8W3/dGJGOEjaBvL4pITwSg5WZt/7fDpGYkro4P//TnMMcF3iRAOm+XQywatNISuBYKQvOdy16Lw0XQyhV37pt0ixwIDAQAB

states/email/exim4/dkim/20160621.cryhavoc.org.uk.pem.txt

@@ -0,0 +1 @@
+k=rsa;p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDoEgY4ekHBKJFey4JtZOO9K0bc25aYKGZiUMd+ESgwZfB3uP0JYxdII8CKLYpHFopmPs8mBW9pNs9L2Iyl6U4v4EE+LwHAhz7uZJfpLylmjQrfb9x72AQONGb4AiK7drc4jbcHr80gMorr27RE9RuYe00U4HdERGwjWcU7rJaRzQIDAQAB

states/email/exim4/dkim/20160621.lunch.org.uk.pem.txt

@@ -0,0 +1 @@
+k=rsa;p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDT6tLjGtCGeZz7MtLq2AazdP7CojC1Vk6CrY+qvM7/rdhIaL++y28+l6WYQhEO0+0kUYNtGewjhvUuq9nEVPvTEh370xOOSDlfAsMTZXZnJFmZGVDegF8mbOg+CQSWqmKRPCmDFsTy1ablh9JnxCIk6q/hiMLfsM1qEO51Wafw/wIDAQAB

states/email/exim4/dkim/bear-cave.org.uk.pem

@@ -0,0 +1,6 @@
+-----BEGIN PUBLIC KEY-----
+MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC97rpW4HWK3q4TIjQnWO6WQZxa
+1EPPRCJJp3yYcjej8ierPPA420RWm3hyUbfPvwN9ynUXPVfrYYj7FJWMR8W3/dGJ
+GOEjaBvL4pITwSg5WZt/7fDpGYkro4P//TnMMcF3iRAOm+XQywatNISuBYKQvOdy
+16Lw0XQyhV37pt0ixwIDAQAB
+-----END PUBLIC KEY-----

states/email/exim4/dkim/cryhavoc.org.uk.pem

@@ -0,0 +1,6 @@
+-----BEGIN PUBLIC KEY-----
+MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDoEgY4ekHBKJFey4JtZOO9K0bc
+25aYKGZiUMd+ESgwZfB3uP0JYxdII8CKLYpHFopmPs8mBW9pNs9L2Iyl6U4v4EE+
+LwHAhz7uZJfpLylmjQrfb9x72AQONGb4AiK7drc4jbcHr80gMorr27RE9RuYe00U
+4HdERGwjWcU7rJaRzQIDAQAB
+-----END PUBLIC KEY-----

states/email/exim4/dkim/lunch.org.uk.pem

@@ -0,0 +1,6 @@
+-----BEGIN PUBLIC KEY-----
+MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDT6tLjGtCGeZz7MtLq2AazdP7C
+ojC1Vk6CrY+qvM7/rdhIaL++y28+l6WYQhEO0+0kUYNtGewjhvUuq9nEVPvTEh37
+0xOOSDlfAsMTZXZnJFmZGVDegF8mbOg+CQSWqmKRPCmDFsTy1ablh9JnxCIk6q/h
+iMLfsM1qEO51Wafw/wIDAQAB
+-----END PUBLIC KEY-----

states/email/exim4/local_check_data

@@ -0,0 +1,41 @@
+  # From rspamd docs.
+
+  # skip scanning for authenticated users (if desired?)
+  accept authenticated = *
+
+  # scan the message with rspamd
+  warn spam = Debian-exim:true
+  # This will set variables as follows:
+  # $spam_action is the action recommended by rspamd
+  # $spam_score is the message score (we unlikely need it)
+  # $spam_score_int is spam score multiplied by 10
+  # $spam_report lists symbols matched & protocol messages
+  # $spam_bar is a visual indicator of spam/ham level
+
+  # use greylisting available in rspamd v1.3+
+  #defer message    = Please try again later
+  #      condition  = ${if eq{$spam_action}{soft reject}}
+
+  #deny  message    = Message discarded as high-probability spam
+  #      condition  = ${if eq{$spam_action}{reject}}
+
+  # Remove foreign headers
+  warn remove_header = x-spam-bar : x-spam-score : x-spam-report : x-spam-status
+
+  # add spam-score and spam-report header when "add header" action is recommended by rspamd
+  warn
+    condition  = ${if eq{$spam_action}{add header}}
+    add_header = X-Spam-Score: $spam_score ($spam_bar)
+    add_header = X-Spam-Report: $spam_report
+
+  # add x-spam-status header if message is not ham
+  warn
+    ! condition  = ${if match{$spam_action}{^no action\$|^greylist\$}}
+    add_header = X-Spam-Status: Yes
+
+  # add x-spam-bar header if score is positive
+  warn
+    condition = ${if >{$spam_score_int}{0}}
+    add_header = X-Spam-Bar: $spam_bar
+
+

states/email/exim4/update-exim4.conf.conf

@@ -0,0 +1,31 @@
+# /etc/exim4/update-exim4.conf.conf
+#
+# Edit this file and /etc/mailname by hand and execute update-exim4.conf
+# yourself or use 'dpkg-reconfigure exim4-config'
+#
+# Please note that this is _not_ a dpkg-conffile and that automatic changes
+# to this file might happen. The code handling this will honor your local
+# changes, so this is usually fine, but will break local schemes that mess
+# around with multiple versions of the file.
+#
+# update-exim4.conf uses this file to determine variable values to replace
+# the DEBCONFsomethingDEBCONF strings in the configuration template files.
+#
+# Most settings found in here do have corresponding questions in the
+# Debconf configuration, but not all of them.
+#
+# This is a Debian specific file
+
+dc_eximconfig_configtype='smarthost'
+dc_other_hostnames='bear-cave.org.uk:*.bear-cave.org.uk:lunch.org.uk:*.lunch.org.uk:cryhavoc.org.uk:cowboybuilder.org.uk:oxfordbeginnersession.org.uk'
+dc_local_interfaces=''
+dc_readhost=''
+dc_relay_domains=''
+dc_minimaldns='false'
+dc_relay_nets=''
+dc_smarthost='smtpout.mythic-beasts.com'
+CFILEMODE='644'
+dc_use_split_config='true'
+dc_hide_mailname='false'
+dc_mailname_in_oh='true'
+dc_localdelivery='dovecot_home'

states/email/init.sls

@@ -0,0 +1,4 @@
+include:
+  - email/dovecot
+  - email/rspamd
+  - email/exim4

states/email/rspamd.sls

@@ -0,0 +1,20 @@
+# Stock bullseye rspamd doesn't start.
+rspamd:
+  pkg.installed:
+    - name: rspamd
+    - fromrepo: bullseye-backports
+
+rspamd_conf:
+  file.recurse:
+    - name: /etc/rspamd/local.d
+    - dir_mode: '0755'
+    - file_mode: '0644'
+    - source: salt://email/rspamd/local.d
+
+rspamd_service:
+  service.running:
+    - name: rspamd
+    - enable: true
+    - watch:
+      - pkg: rspamd
+      - file: /etc/rspamd/local.d

states/email/rspamd/local.d/ip_whitelist.map

@@ -0,0 +1 @@
+# 2a00:1098:8:d6::1/64

states/email/rspamd/local.d/multimap.conf

@@ -0,0 +1,6 @@
+IP_WHITELIST {
+    type = "ip";
+    prefilter = "true";
+    map = "/${LOCAL_CONFDIR}/local.d/ip_whitelist.map";
+    action = "accept";
+}

states/email/rspamd/local.d/redis.conf

@@ -0,0 +1,2 @@
+write_servers = "localhost";
+read_servers = "localhost";

states/firewalls/scabbers.sls

@@ -5,6 +5,12 @@ scabbers_public:
     - services:
       - dhcpv6-client
       - ssh
+      - imap
+      - imaps
+      - managesieve
+      - smtp
+      - smtps
+      - smtp-submission
     - prune_services: True
     - require:
       - firewalld

states/top.sls

@@ -22,6 +22,7 @@ base:
     - backup
     - backup/scabbers
     - dottes_website
+    - email
     - fail2ban
     - firewalls/scabbers
     - gitea