dovecot: Update config for 2.3

Signed-off-by: Florian Pritz <bluewind@xinu.at>

roles/dovecot/tasks/main.yml

@@ -3,6 +3,9 @@
 - name: install dovecot
   pacman: name=dovecot,pigeonhole state=present
 
+- name: create dhparam
+  shell: openssl dhparam -out /etc/dovecot/dh.pem 4096 creates=/etc/dovecot/dh.pem
+
 - name: install dovecot.conf
   template: src=dovecot.conf.j2 dest=/etc/dovecot/dovecot.conf owner=root group=root mode=0644
   notify:

roles/dovecot/templates/dovecot.conf.j2

@@ -86,7 +86,8 @@ login_log_format_elements = "user=<%u> method=%m rip=%r lip=%l mpid=%e %c %k"
 ssl_cert = </etc/letsencrypt/live/{{mail_domain}}/fullchain.pem
 ssl_key = </etc/letsencrypt/live/{{mail_domain}}/privkey.pem
 ssl_prefer_server_ciphers = yes
-ssl_protocols = !SSLv3
+ssl_protocol_min = TLSv1
+ssl_dh=</etc/dovecot/dh.pem
 ssl_options = no_compression
 
 ssl_cipher_list = EDH+CAMELLIA:EDH+aRSA:EECDH+aRSA+AESGCM:EECDH+aRSA+SHA384:EECDH+aRSA+SHA256:EECDH:+CAMELLIA256:+AES256+CAMELLIA128:+AES128:+SSLv3:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!DSS:!RC4:!SEED:!ECDSA:CAMELLIA256-SHA:AES256-SHA:CAMELLIA128-SHA:AES128-SHA