Refactored how SSL certs are configured for nginx

Made a separate ACME module to handle requesting certs from multiple
machines. Right now, the module only supports exactly one wildcard cert.
It might make sense to have cache.kilonull.com use a cert specific to
its subdomain rather than also requesting a wildcard cert (or maybe the
nginx on its host shouldn't care about TLS and it should be node's
responsibility).

modules/nix/default.nix

@@ -7,7 +7,7 @@
 }:
 with lib; let
   cfg = config.aa.nix;
-  selfHostedCacheHost = "http://192.168.113.69/";
+  selfHostedCacheHost = "https://cache.kilonull.com/";
 in {
   options.aa.nix = with types; {
     enable = mkEnableOption "manage nix configuration.";

modules/security/acme/default.nix

@@ -0,0 +1,56 @@
+{
+  options,
+  config,
+  lib,
+  pkgs,
+  format,
+  ...
+}:
+with lib; let
+  cfg = config.aa.security.acme;
+in {
+  options.aa.security.acme = with types; {
+    enable = mkEnableOption "Automatic Certificate Management Environment (ACME)";
+    useStaging = mkOption {
+      type = bool;
+      description = ''
+        Use the staging environment (use when configuring for the first time to
+        avoid being locked out).
+      '';
+      default = false;
+    };
+    domainName = mkOption {
+      type = str;
+      description = "The domain to request a wildcard cert for.";
+    };
+    dnsCredentialsFile = mkOption {
+      type = path;
+      description = "The path to the credentials file for the DNS provider.";
+    };
+  };
+
+  # Only supports exactly one wildcard cert using Cloudflare (only use case I have)
+  config = mkIf cfg.enable {
+    security.acme = {
+      acceptTerms = true;
+      defaults = {
+        email = config.aa.user.email;
+        group = "nginx";
+        server = mkIf cfg.useStaging "https://acme-staging-v02.api.letsencrypt.org/directory";
+      };
+
+      # Wildcard cert
+      certs."${cfg.domainName}" = {
+        group = "nginx";
+        dnsProvider = "cloudflare";
+        # Private network resolves *.kilonull.com to private servers but `lego`
+        # (acme client under the hood) needs to find the cloudflare nameservers
+        # to determine the correct zone to apply changes in. Use cloudflare's
+        # own DNS to make `lego` happy (will resolve names to a public IP).
+        dnsResolver = "1.1.1.1:53";
+        credentialsFile = cfg.dnsCredentialsFile;
+        extraDomainNames = [("*." + cfg.domainName)];
+      };
+    };
+  };
+}

modules/services/adguardhome/default.nix

@@ -11,6 +11,14 @@ with lib; let
 in {
   options.aa.services.adguardhome = with types; {
     enable = mkEnableOption "adguardhome";
+    acmeCertName = mkOption {
+      type = str;
+      default = "";
+      description = ''
+        If set to a non-empty string, forces SSL with the supplied acme
+        certificate.
+      '';
+    };
   };
 
   config = mkIf cfg.enable {
@@ -26,36 +34,15 @@ in {
     services.nginx = {
       enable = true;
       recommendedProxySettings = true;
-      virtualHosts."adguardhome.kilonull.com" = {
-        forceSSL = true;
-        useACMEHost = "kilonull.com";
+      virtualHosts."adguardhome.kilonull.com" =
+        {
           locations."/" = {
             proxyPass = "http://127.0.0.1:3000";
           };
-      };
-    };
-
-    # So that nginx has access to the ACME certs
-    users.users.nginx.extraGroups = ["acme"];
-
-    age.secrets.cf_dns_kilonull.file = ../../../secrets/cf_dns_kilonull.age;
-
-    security.acme = {
-      # NOTE: Uncomment line below when testing changes
-      # defaults.server = "https://acme-staging-v02.api.letsencrypt.org/directory";
-      acceptTerms = true;
-      defaults.email = "iam@alejandr0angul0.dev";
-
-      # Wildcard cert
-      certs."kilonull.com" = {
-        dnsProvider = "cloudflare";
-        # Private network resolves *.kilonull.com to private servers but `lego`
-        # (acme client under the hood) needs to find the cloudflare nameservers
-        # to determine the correct zone to apply changes in. Use cloudflare's
-        # own DNS to make `lego` happy (will resolve names to a public IP).
-        dnsResolver = "1.1.1.1:53";
-        credentialsFile = config.age.secrets.cf_dns_kilonull.path;
-        extraDomainNames = ["*.kilonull.com"];
+        }
+        // lib.optionalAttrs (cfg.acmeCertName != "") {
+          forceSSL = true;
+          useACMEHost = cfg.acmeCertName;
         };
     };
 

modules/services/nextcloud/default.nix

@@ -11,6 +11,14 @@ with lib; let
 in {
   options.aa.services.nextcloud = with types; {
     enable = mkEnableOption "nextcloud";
+    acmeCertName = mkOption {
+      type = str;
+      default = "";
+      description = ''
+        If set to a non-empty string, forces SSL with the supplied acme
+        certificate.
+      '';
+    };
   };
 
   config = mkIf cfg.enable {
@@ -47,9 +55,9 @@ in {
     };
 
     # nextcloud module configures nginx, just need to specify SSL stuffs here
-    services.nginx.virtualHosts.${config.services.nextcloud.hostName} = {
+    services.nginx.virtualHosts.${config.services.nextcloud.hostName} = mkIf (cfg.acmeCertName != "") {
       forceSSL = true;
-      useACMEHost = "kilonull.com";
+      useACMEHost = cfg.acmeCertName;
     };
 
     networking.firewall.allowedTCPPorts = [80 443];

modules/services/nix-serve/default.nix

@@ -19,6 +19,14 @@ in {
       type = str;
       description = "The subdomain to use.";
     };
+    acmeCertName = mkOption {
+      type = str;
+      default = "";
+      description = ''
+        If set to a non-empty string, forces SSL with the supplied acme
+        certificate.
+      '';
+    };
   };
 
   config = mkIf cfg.enable {
@@ -38,8 +46,8 @@ in {
 
       nginx = {
         enable = true;
-        virtualHosts = {
-          "${cfg.subdomain_name}.${cfg.domain_name}" = {
+        virtualHosts."${cfg.subdomain_name}.${cfg.domain_name}" =
+          {
             serverAliases = ["${cfg.subdomain_name}"];
             locations."/".extraConfig = ''
               proxy_pass http://localhost:${toString config.services.nix-serve.port};
@@ -47,13 +55,16 @@ in {
               proxy_set_header X-Real-IP $remote_addr;
               proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
             '';
-          };
+          }
+          // lib.optionalAttrs (cfg.acmeCertName != "") {
+            forceSSL = true;
+            useACMEHost = cfg.acmeCertName;
           };
       };
     };
 
     networking.firewall = {
-      allowedTCPPorts = [80];
+      allowedTCPPorts = [80 443];
     };
   };
 }

secrets/secrets.nix

@@ -2,8 +2,9 @@ let
   # Remember to pass '--identity identities/me.txt` when using this key
   users.me = "age1yubikey1qdwgvfqrcqmyw56ux7azuvqr6f8nanszu27nztvxmn4utmplgxctzt90g25";
 
+  machines.gospel = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIGDzjXVoQEfO9JIcFbp56EvQ0oBdr9Cmhxp4z0ih+ZEZ";
   machines.node = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIETLBnc8kJokmFiA28BaSYpeE7flY1W0SM5C1pWv/tOv";
 in {
-  "cf_dns_kilonull.age".publicKeys = [users.me machines.node];
+  "cf_dns_kilonull.age".publicKeys = [users.me machines.node machines.gospel];
   "nextcloud_admin.age".publicKeys = [users.me machines.node];
 }

systems/x86_64-linux/gospel/default.nix

@@ -8,6 +8,8 @@
     ./zfs.nix
   ];
 
+  age.secrets.cf_dns_kilonull.file = ../../../secrets/cf_dns_kilonull.age;
+
   aa = {
     nix.enable = true;
 
@@ -19,11 +21,19 @@
 
     apps.yubikey.enable = true;
 
+    security.acme = {
+      enable = true;
+      # useStaging = true;
+      domainName = "kilonull.com";
+      dnsCredentialsFile = config.age.secrets.cf_dns_kilonull.path;
+    };
+
     services.openssh.enable = true;
     services.nix-serve = {
       enable = true;
       domain_name = "kilonull.com";
-      subdomain_name = "gospel";
+      subdomain_name = "cache";
+      acmeCertName = "kilonull.com";
     };
     services.printing.enable = true;
     services.tailscale = {

systems/x86_64-linux/node/default.nix

@@ -8,6 +8,8 @@
     ./zfs.nix
   ];
 
+  age.secrets.cf_dns_kilonull.file = ../../../secrets/cf_dns_kilonull.age;
+
   aa = {
     nix.enable = true;
     nix.useSelfhostedCache = true;
@@ -18,8 +20,20 @@
       configureServerRouting = true;
     };
     services.openssh.enable = true;
-    services.adguardhome.enable = true;
-    services.nextcloud.enable = true;
+    services.adguardhome = {
+      enable = true;
+      acmeCertName = "kilonull.com";
+    };
+    services.nextcloud = {
+      enable = true;
+      acmeCertName = "kilonull.com";
+    };
+
+    security.acme = {
+      enable = true;
+      domainName = "kilonull.com";
+      dnsCredentialsFile = config.age.secrets.cf_dns_kilonull.path;
+    };
 
     system.zfs.enable = true;
     system.monitoring.enable = true;