bitcoind: add netns

- Adds bitcoind to netns-isolation.services
- Adds rpcbind and rpcallowip options to allow using bitcoind with
  network namespaces
- Adds bind option (defaults to localhost), used as target of hidden service
- Makes bitcoind-import-banlist run in netns

modules/bitcoind.nix

@@ -18,6 +18,7 @@ let
     ${optionalString (cfg.assumevalid != null) "assumevalid=${cfg.assumevalid}"}
 
     # Connection options
+    ${optionalString cfg.listen "bind=${cfg.bind}"}
     ${optionalString (cfg.port != null) "port=${toString cfg.port}"}
     ${optionalString (cfg.proxy != null) "proxy=${cfg.proxy}"}
     listen=${if cfg.listen then "1" else "0"}
@@ -30,6 +31,8 @@ let
       (rpcUser: "rpcauth=${rpcUser.name}:${rpcUser.passwordHMAC}")
       (attrValues cfg.rpc.users)
     }
+    ${lib.concatMapStrings (rpcbind: "rpcbind=${rpcbind}\n") cfg.rpcbind}
+    ${lib.concatMapStrings (rpcallowip: "rpcallowip=${rpcallowip}\n") cfg.rpcallowip}
     ${optionalString (cfg.rpcuser != null) "rpcuser=${cfg.rpcuser}"}
     ${optionalString (cfg.rpcpassword != null) "rpcpassword=${cfg.rpcpassword}"}
 
@@ -68,6 +71,13 @@ in {
         default = "/var/lib/bitcoind";
         description = "The data directory for bitcoind.";
       };
+      bind = mkOption {
+        type = types.str;
+        default = "127.0.0.1";
+        description = ''
+          Bind to given address and always listen on it.
+        '';
+      };
       user = mkOption {
         type = types.str;
         default = "bitcoin";
@@ -117,6 +127,20 @@ in {
           '';
         };
       };
+      rpcbind = mkOption {
+        type = types.listOf types.str;
+        default = [ "127.0.0.1" ];
+        description = ''
+          Bind to given address to listen for JSON-RPC connections.
+        '';
+      };
+      rpcallowip = mkOption {
+        type = types.listOf types.str;
+        default = [ "127.0.0.1" ];
+        description = ''
+          Allow JSON-RPC connections from specified source.
+        '';
+      };
       rpcuser = mkOption {
           type = types.nullOr types.str;
           default = "bitcoinrpc";