Merge branch 'postfix-config' into 'master'

postfix: migrate more options to services.postfix.config

See merge request simple-nixos-mailserver/nixos-mailserver!418

mail-server/postfix.nix

@@ -248,8 +248,6 @@ in
 
     services.postfix = {
       enable = true;
-      hostname = "${cfg.sendingFqdn}";
-      networksStyle = "host";
       mapFiles."valias" = valiases_file;
       mapFiles."regex_valias" = regex_valiases_file;
       mapFiles."vaccounts" = vaccounts_file;
@@ -266,13 +264,8 @@ in
       ]);
 
       config = {
-        smtpd_tls_chain_files = [
-          "${keyPath}"
-          "${certificatePath}"
-        ];
-
-        # Extra Config
-        mydestination = "";
+        myhostname = cfg.sendingFqdn;
+        mydestination = ""; # disable local mail delivery
         recipient_delimiter = cfg.recipientDelimiter;
         smtpd_banner = "${cfg.fqdn} ESMTP NO UCE";
         disable_vrfy_command = true;
@@ -299,6 +292,7 @@ in
           ]
         );
         virtual_transport = "lmtp:unix:/run/dovecot2/dovecot-lmtp";
+
         # Avoid leakage of X-Original-To, X-Delivered-To headers between recipients
         lmtp_destination_recipient_limit = "1";
 
@@ -325,6 +319,12 @@ in
           "check_policy_service unix:/run/dovecot2/quota-status"
         ];
 
+        # The X509 private key followed by the corresponding certificate
+        smtpd_tls_chain_files = [
+          "${keyPath}"
+          "${certificatePath}"
+        ];
+
         # TLS for incoming mail is optional
         smtpd_tls_security_level = "may";