Revert "nixos: Remove torify module"

tsocks is still useful because it's less strict

This reverts commit 1b26faeb69.

nixos/modules/module-list.nix

@@ -307,6 +307,7 @@
   ./services/security/fprot.nix
   ./services/security/frandom.nix
   ./services/security/haveged.nix
+  ./services/security/torify.nix
   ./services/security/tor.nix
   ./services/security/torsocks.nix
   ./services/system/cloud-init.nix

nixos/modules/services/security/torify.nix

@@ -0,0 +1,69 @@
+{ config, lib, pkgs, ... }:
+with lib;
+let
+
+  cfg = config.services.tor;
+
+  torify = pkgs.writeTextFile {
+    name = "torify";
+    text = ''
+        #!${pkgs.stdenv.shell}
+        TSOCKS_CONF_FILE=${pkgs.writeText "tsocks.conf" cfg.torify.config} LD_PRELOAD="${pkgs.tsocks}/lib/libtsocks.so $LD_PRELOAD" "$@"
+    '';
+    executable = true;
+    destination = "/bin/torify";
+  };
+
+in
+
+{
+
+  ###### interface
+  
+  options = {
+  
+    services.tor.torify = {
+
+      enable = mkOption {
+        default = cfg.client.enable;
+        description = ''
+          Whether to build torify scipt to relay application traffic via TOR.
+        '';
+      };
+
+      server = mkOption {
+        default = "localhost:9050";
+        example = "192.168.0.20";
+        description = ''
+          IP address of TOR client to use.
+        '';
+      };
+
+      config = mkOption {
+        default = "";
+        description = ''
+          Extra configuration. Contents will be added verbatim to TSocks
+          configuration file.
+        '';
+      };
+
+    };
+
+  };
+
+  ###### implementation
+
+  config = mkIf cfg.torify.enable {
+
+    environment.systemPackages = [ torify ];  # expose it to the users
+
+    services.tor.torify.config = ''
+      server = ${toString(head (splitString ":" cfg.torify.server))}
+      server_port = ${toString(tail (splitString ":" cfg.torify.server))}
+
+      local = 127.0.0.0/255.128.0.0
+      local = 127.128.0.0/255.192.0.0
+    '';
+  };
+
+}