Allow to pass services as buffer to net_addr

lib/structs.js

@@ -761,7 +761,7 @@ exports.net_addr = {
    * included in short mode (current time by default)
    * @param {number=} opts.stream - Stream number of the node, not
    * included in short mode (1 by default)
-   * @param {Object=} opts.services -
+   * @param {(Object|Buffer)=} opts.services -
    * [Services]{@link module:bitmessage/structs.ServicesBitfield}
    * provided by the node (`NODE_NETWORK` by default)
    * @param {string} opts.host - IPv4/IPv6 address of the node
@@ -788,7 +788,12 @@ exports.net_addr = {
     }
     var services = opts.services ||
                    ServicesBitfield().set(ServicesBitfield.NODE_NETWORK);
-    services.buffer.copy(buf, shift);
+    if (Buffer.isBuffer(services)) {
+      assert(services.length === 8, "Bad services buffer length");
+    } else {
+      services = services.buffer;
+    }
+    services.copy(buf, shift);
     inet_pton(opts.host).copy(buf, shift + 8);
     buf.writeUInt16BE(opts.port, shift + 24);
     return buf;

test.js

@@ -414,6 +414,16 @@ describe("Common structures", function() {
       var opts = {host: " 127.0.0.1", port: 1234};
       expect(net_addr.encode.bind(null, opts)).to.throw(/bad octet/i);
     });
+
+    it("should allow to pass services as Buffer", function() {
+      var services = Buffer(8);
+      var res = net_addr.decode(net_addr.encode({
+        host: "1.2.3.4",
+        port: 1234,
+        services: services,
+      }));
+      expect(bufferEqual(res.services.buffer, services)).to.be.true;
+    });
   });
 
   describe("inv_vect", function() {