feat(vesuvio): add maddy

secrets/secrets.nix

@@ -41,4 +41,6 @@ in
   "etna/vmauthEnv.age".publicKeys = main ++ [ etna ];
   "etna/upsdUserPass.age".publicKeys = main ++ [ etna ];
   "etna/cobaltTokens.age".publicKeys = main ++ [ etna ];
+
+  "vesuvio/maddyEnv.age".publicKeys = main ++ [ vesuvio ];
 }

secrets/vesuvio/maddyEnv.age

@@ -0,0 +1,14 @@
+-----BEGIN AGE ENCRYPTED FILE-----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+-----END AGE ENCRYPTED FILE-----

systems/etna/postgresql.nix

@@ -7,6 +7,14 @@
 
       settings.port = 5432;
       enableTCPIP = true;
+
+      ensureDatabases = [
+        "maddy"
+      ];
+
+      authentication = ''
+        host maddy maddy vesuvio.fossa-macaroni.ts.net scram-sha-256
+      '';
     };
 
     postgresqlBackup = {

systems/vesuvio/default.nix

@@ -4,6 +4,7 @@
     ./certificates.nix
     ./frp.nix
     ./hetzner.nix
+    ./mail
     ./nginx.nix
   ];
 

systems/vesuvio/mail/default.nix

@@ -0,0 +1,6 @@
+{
+  imports = [
+    ./maddy.nix
+    ./mta-sts.nix
+  ];
+}

systems/vesuvio/mail/maddy.nix

@@ -0,0 +1,203 @@
+{ config, _utils, ... }:
+let
+  hostname = "mx1.uku3lig.net";
+  certLocation = config.security.acme.certs.${hostname}.directory;
+
+  env = _utils.setupSingleSecret config "maddyEnv" { };
+in
+{
+  imports = [ env.generate ];
+
+  security.acme.certs.${hostname} = {
+    group = config.services.maddy.group;
+    extraLegoRenewFlags = [ "--reuse-key" ]; # soopyc said its more secure
+  };
+
+  services.maddy = {
+    enable = true;
+    inherit hostname;
+    primaryDomain = "uku3lig.net";
+    localDomains = [
+      "$(primary_domain)"
+      "uku.moe"
+    ];
+
+    tls = {
+      loader = "file";
+      certificates = [
+        {
+          certPath = "${certLocation}/fullchain.pem";
+          keyPath = "${certLocation}/key.pem";
+        }
+      ];
+    };
+
+    config = ''
+      ## common stuff
+
+      auth.pass_table local_authdb {
+        table sql_table {
+          driver postgres
+          dsn "host=etna password={env:POSTGRES_PASSWORD} dbname=maddy sslmode=disable"
+          table_name passwords
+        }
+      }
+
+      storage.imapsql local_mailboxes {
+        driver postgres
+        dsn "host=etna password={env:POSTGRES_PASSWORD} dbname=maddy sslmode=disable"
+        # TODO: imap_filter https://maddy.email/reference/storage/imap-filters/
+      }
+
+      # chain of steps applied to recipients
+      # each step is a lookup table
+      table.chain local_rewrites {
+        # this removes the +suffix part from the address
+        optional_step regexp "(.+)\+(.+)@(.+)" "$1@$3"
+        optional_step static {
+          entry postmaster postmaster@$(primary_domain)
+        }
+      }
+
+      ## message reception
+
+      msgpipeline local_routing {
+        # TODO: checks (rspamd)
+
+        modify {
+          replace_rcpt &local_rewrites
+        }
+
+        # catch-all setup inspired by https://github.com/foxcpp/maddy/issues/243#issuecomment-1406567636
+        # we don't have a destination_in clause because there is only one imap account
+        destination $(local_domains) {
+          modify {
+            replace_rcpt regexp ".*" "hi@uku.moe"
+          }
+
+          deliver_to &local_mailboxes
+        }
+
+        default_destination {
+          reject 550 5.1.1 "User doesn't exist"
+        }
+      }
+
+      smtp tcp://0.0.0.0:25 {
+        limits {
+          # Up to 20 msgs/sec across max. 10 SMTP connections.
+          all rate 20 1s
+          all concurrency 10
+        }
+
+        dmarc yes
+        check {
+          require_mx_record
+          dkim
+          spf
+        }
+
+        source $(local_domains) {
+          reject 501 5.1.8 "Use internal submission port for outgoing SMTP"
+        }
+
+        default_source {
+          destination postmaster $(local_domains) {
+            deliver_to &local_routing
+          }
+          default_destination {
+            reject 550 5.1.1 "User doesn't exist"
+          }
+        }
+      }
+
+      ## message sending
+
+      target.remote outbound_delivery {
+        limits {
+          # Up to 20 msgs/sec across max. 10 SMTP connections for each recipient domain.
+          destination rate 20 1s
+          destination concurrency 10
+        }
+
+        mx_auth {
+          dane
+          mtasts
+          local_policy {
+            min_tls_level encrypted
+            min_mx_level none
+          }
+        }
+      }
+
+      target.queue remote_queue {
+        target &outbound_delivery
+
+        # sender domain for DSNs (delivery status notifications)
+        autogenerated_msg_domain $(primary_domain)
+
+        # pipeline to know where to send DSNs
+        bounce {
+          destination postmaster $(local_domains) {
+            deliver_to &local_routing
+          }
+          default_destination {
+            reject 550 5.0.0 "Refusing to send DSNs to non-local addresses"
+          }
+        }
+      }
+
+      submission tls://0.0.0.0:465 tcp://0.0.0.0:587 {
+        limits {
+          # Up to 50 msgs/sec across any amount of SMTP connections.
+          all rate 50 1s
+        }
+
+        auth &local_authdb
+
+        source $(local_domains) {
+          # make sure the sender is allowed to send from this server
+          # local_rewrites allows us to use aliases as sender
+          check {
+            authorize_sender {
+              prepare_email &local_rewrites
+              user_to_email identity
+            }
+          }
+
+          # just loop back if we are sending an email to ourselves
+          destination postmaster $(local_domains) {
+            deliver_to &local_routing
+          }
+
+          default_destination {
+            modify {
+              dkim $(primary_domain) $(local_domains) default
+            }
+
+            deliver_to &remote_queue
+          }
+        }
+
+        default_source {
+          reject 501 5.1.8 "Non-local sender domain"
+        }
+      }
+
+      ## IMAP
+      imap tls://0.0.0.0:993 {
+        auth &local_authdb
+        storage &local_mailboxes
+      }
+    '';
+  };
+
+  systemd.services.maddy.serviceConfig.EnvironmentFile = env.path;
+
+  networking.firewall.allowedTCPPorts = [
+    25 # smtp
+    465 # submissions
+    587 # submission (starttls)
+    993 # imaps
+  ];
+}

systems/vesuvio/mail/mta-sts.nix

@@ -0,0 +1,18 @@
+{ _utils, ... }:
+{
+  services.nginx.virtualHosts."mta-sts.uku3lig.net" = {
+    forceSSL = true;
+    enableACME = true;
+    serverAliases = [ "mta-sts.uku.moe" ];
+
+    locations."/.well-known/" = _utils.mkNginxFile {
+      filename = "mta-sts.txt";
+      content = ''
+        version: STSv1
+        mode: enforce
+        mx: mx1.uku3lig.net
+        max_age: 604800
+      '';
+    };
+  };
+}