nixos/podman: Add generic networkSocket interface

(cherry picked from commit 52844efcd67028a481a24103d8e93c7ef2bf4f08)

nixos/modules/virtualisation/podman-network-socket.nix

@@ -0,0 +1,91 @@
+{ config, lib, pkg, ... }:
+let
+  inherit (lib)
+    mkOption
+    types
+    ;
+
+  cfg = config.virtualisation.podman.networkSocket;
+
+in
+{
+  options.virtualisation.podman.networkSocket = {
+    enable = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Make the Podman and Docker compatibility API available over the network
+        with TLS client certificate authentication.
+
+        This allows Docker clients to connect with the equivalents of the Docker
+        CLI <code>-H</code> and <code>--tls*</code> family of options.
+
+        For certificate setup, see https://docs.docker.com/engine/security/protect-access/
+
+        This option is independent of <xref linkend="opt-virtualisation.podman.dockerSocket.enable"/>.
+      '';
+    };
+
+    server = mkOption {
+      type = types.enum [];
+      description = ''
+        Choice of TLS proxy server.
+      '';
+      example = "ghostunnel";
+    };
+
+    openFirewall = mkOption {
+      type = types.bool;
+      default = false;
+      description = ''
+        Whether to open the port in the firewall.
+      '';
+    };
+
+    tls.cacert = mkOption {
+      type = types.path;
+      description = ''
+        Path to CA certificate to use for client authentication.
+      '';
+    };
+
+    tls.cert = mkOption {
+      type = types.path;
+      description = ''
+        Path to certificate describing the server.
+      '';
+    };
+
+    tls.key = mkOption {
+      type = types.path;
+      description = ''
+        Path to the private key corresponding to the server certificate.
+
+        Use a string for this setting. Otherwise it will be copied to the Nix
+        store first, where it is readable by any system process.
+      '';
+    };
+
+    port = mkOption {
+      type = types.port;
+      default = 2376;
+      description = ''
+        TCP port number for receiving TLS connections.
+      '';
+    };
+    listenAddress = mkOption {
+      type = types.str;
+      default = "0.0.0.0";
+      description = ''
+        Interface address for receiving TLS connections.
+      '';
+    };
+  };
+
+  config = {
+    networking.firewall.allowedTCPPorts =
+      lib.optional (cfg.enable && cfg.openFirewall) cfg.port;
+  };
+
+  meta.maintainers = lib.teams.podman.members ++ [ lib.maintainers.roberth ];
+}

nixos/modules/virtualisation/podman.nix

@@ -25,6 +25,7 @@ let
 in
 {
   imports = [
+    ./podman-network-socket.nix
     (lib.mkRenamedOptionModule [ "virtualisation" "podman" "libpod" ] [ "virtualisation" "containers" "containersConf" ])
   ];