nixos/nginx: add kTLS option

2 files changed, 22 insertions, 0 deletions

diff --git a/nixos/modules/services/web-servers/nginx/default.nix b/nixos/modules/services/web-servers/nginx/default.nix
index 5717b86b3be..7f5c3841f1a 100644
--- a/nixos/modules/services/web-servers/nginx/default.nix
+++ b/nixos/modules/services/web-servers/nginx/default.nix
@@ -316,6 +316,9 @@ let
           ${optionalString vhost.rejectSSL ''
             ssl_reject_handshake on;
           ''}
+          ${optionalString (hasSSL && vhost.kTLS) ''
+            ssl_conf_command Options KTLS;
+          ''}
 
           ${mkBasicAuth vhostName vhost}
 
@@ -821,6 +824,14 @@ in
       }
 
       {
+        assertion = any (host: host.kTLS) (attrValues virtualHosts) -> versionAtLeast cfg.package.version "1.21.4";
+        message = ''
+          services.nginx.virtualHosts.<name>.kTLS requires nginx version
+          1.21.4 or above; see the documentation for services.nginx.package.
+        '';
+      }
+
+      {
         assertion = all (host: !(host.enableACME && host.useACMEHost != null)) (attrValues virtualHosts);
         message = ''
           Options services.nginx.service.virtualHosts.<name>.enableACME and
diff --git a/nixos/modules/services/web-servers/nginx/vhost-options.nix b/nixos/modules/services/web-servers/nginx/vhost-options.nix
index 7ee041d3721..7f49ce9586c 100644
--- a/nixos/modules/services/web-servers/nginx/vhost-options.nix
+++ b/nixos/modules/services/web-servers/nginx/vhost-options.nix
@@ -147,6 +147,17 @@ with lib;
       '';
     };
 
+    kTLS = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Whether to enable kTLS support.
+        Implementing TLS in the kernel (kTLS) improves performance by significantly
+        reducing the need for copying operations between user space and the kernel.
+        Required Nginx version 1.21.4 or later.
+      '';
+    };
+
     sslCertificate = mkOption {
       type = types.path;
       example = "/var/host.cert";