Implement messages.version

README.md

@@ -36,7 +36,7 @@ API documentation is available [here](https://bitchan.github.io/bitmessage/docs/
   - [x] service features
   - [x] pubkey features
 - [ ] Message types
-  - [ ] version
+  - [x] version
   - [ ] verack
   - [ ] addr
   - [ ] inv

lib/index.js

@@ -5,6 +5,9 @@
 
 "use strict";
 
+/** Current protocol version. */
+exports.PROTOCOL_VERSION = 3;
+
 /** [Common structures.]{@link module:bitmessage/structs} */
 exports.structs = require("./structs");
 /** [Messages.]{@link module:bitmessage/messages} */

lib/messages.js

@@ -3,3 +3,97 @@
  * @see {@link https://bitmessage.org/wiki/Protocol_specification#Message_types}
  * @module bitmessage/messages
  */
+
+"use strict";
+
+var assert = require("./util").assert;
+var structs = require("./structs");
+var UserAgent = require("./user-agent");
+var util = require("./util");
+
+/**
+ * Version message.
+ * @see {@link https://bitmessage.org/wiki/Protocol_specification#version}
+ * @namespace
+ */
+exports.version = {
+  /** Random nonce used to detect connections to self. */
+  NONCE: new Buffer("20bde0a3355dad78", "hex"),
+
+  /**
+   * Decode version payload.
+   * NOTE: `nonce` is copied.
+   * @param {Buffer} buf - Buffer that starts with encoded version
+   * payload
+   * @return {Object} Decoded version structure.
+   */
+  decode: function(payload) {
+    // 4 + 8 + 8 + 26 + 26 + 8 + (1+) + (1+)
+    assert(payload.length >= 82, "Message payload is too small");
+    var protoVersion = payload.readUInt32BE(0, true);
+    var services = structs.serviceFeatures.decode(payload.slice(4, 12));
+    var time = util.readTime64BE(payload, 12);
+    var short = {short: true};
+    var addrRecv = structs.net_addr.decode(payload.slice(20, 46), short);
+    var addrFrom = structs.net_addr.decode(payload.slice(46, 72), short);
+    var nonce = new Buffer(8);
+    payload.copy(nonce, 0, 72, 80);
+    var decodedUa = UserAgent.decode(payload.slice(80));
+    var decodedStreamNumbers = structs.var_int_list.decode(decodedUa.rest);
+    return {
+      version: protoVersion,
+      services: services,
+      time: time,
+      remoteHost: addrRecv.host,
+      remotePort: addrRecv.port,
+      port: addrFrom.port,
+      nonce: nonce,
+      software: decodedUa.software,
+      streamNumbers: decodedStreamNumbers.list,
+      // NOTE(Kagami): Real data length. It may be some gap between end
+      // of stream numbers list and end of payload:
+      //     [payload..............[stream numbers]xxxx]
+      // We are currently ignoring that.
+      length: 80 + decodedUa.length + decodedStreamNumbers.length,
+    };
+  },
+
+  /**
+   * Encode version payload.
+   * @param {Object} opts - Version options
+   * @return {Buffer} Encoded version payload.
+   */
+  encode: function(opts) {
+    // Deal with default options.
+    var services = opts.services || [structs.serviceFeatures.NODE_NETWORK];
+    var time = opts.time || new Date();
+    var nonce = opts.nonce || exports.version.NONCE;
+    var software = opts.software || UserAgent.SELF;
+    var streamNumbers = opts.streamNumbers || [1];
+    // Start encoding.
+    var protoVersion = new Buffer(4);
+    protoVersion.writeUInt32BE(require("./").PROTOCOL_VERSION, 0);
+    var addrRecv = structs.net_addr.encode({
+      services: services,
+      host: opts.remoteHost,
+      port: opts.remotePort,
+      short: true,
+    });
+    var addrFrom = structs.net_addr.encode({
+      services: services,
+      host: "127.0.0.1",
+      port: opts.port,
+      short: true,
+    });
+    return Buffer.concat([
+      protoVersion,
+      structs.serviceFeatures.encode(services),
+      util.writeTime64BE(null, time),
+      addrRecv,
+      addrFrom,
+      nonce,
+      UserAgent.encode(software),
+      structs.var_int_list.encode(streamNumbers),
+    ]);
+  },
+};

lib/structs.js

@@ -59,13 +59,14 @@ var message = exports.message = {
     command = command.slice(0, firstNonNull).toString("ascii");
     var payloadLength = buf.readUInt32BE(16, true);
     assert(payloadLength <= 262144, "Payload is too big");
-    var checksum = buf.slice(20, 24);
     var length = 24 + payloadLength;
+    assert(buf.length >= length, "Truncated payload");
+    var checksum = buf.slice(20, 24);
     // NOTE(Kagami): We do copy instead of slice to protect against
     // possible source buffer modification by user.
     var payload = new Buffer(payloadLength);
     buf.copy(payload, 0, 24, length);
-    assert(bufferEqual(checksum, getmsgchecksum(payload)), "Bad checkum");
+    assert(bufferEqual(checksum, getmsgchecksum(payload)), "Bad checksum");
     var rest = buf.slice(length);
     return {command: command, payload: payload, length: length, rest: rest};
   },
@@ -393,7 +394,7 @@ exports.net_addr = {
   encode: function(opts) {
     // Be aware of `Buffer.slice` quirk in browserify:
     // <http://git.io/lNZF1A> (does not modify parent buffer's memory in
-    // old browsers).
+    // old browsers). So we use offset instead of `buf = buf.slice`.
     var buf, shift;
     if (opts.short) {
       buf = new Buffer(26);
@@ -404,7 +405,8 @@ exports.net_addr = {
       time = Math.floor(time.getTime() / 1000);
       buf.writeUInt32BE(Math.floor(time / 4294967296), 0, true);  // high32
       buf.writeUInt32BE(time % 4294967296, 4, true);  // low32
-      buf.writeUInt32BE(opts.stream, 8);
+      var stream = opts.stream || 1;
+      buf.writeUInt32BE(stream, 8);
       shift = 12;
     }
     var services = opts.services || [serviceFeatures.NODE_NETWORK];

lib/util.js

@@ -1,7 +1,58 @@
 "use strict";
 
-exports.assert = function(condition, message) {
+var assert = exports.assert = function(condition, message) {
   if (!condition) {
     throw new Error(message || "Assertion failed");
   }
 };
+
+// Missing methods to read/write 64 bits integers from/to buffers.
+// TODO(Kagami): Use this helpers in structs, pow, platform.
+
+var MAX_SAFE_INTEGER = exports.MAX_SAFE_INTEGER = 9007199254740991;
+
+exports.readUInt64BE = function(buf, offset, noAssert) {
+  offset = offset || 0;
+  var hi = buf.readUInt32BE(offset, noAssert);
+  var lo = buf.readUInt32BE(offset + 4, noAssert);
+  // Max safe number = 2^53 - 1 =
+  // 0b0000000000011111111111111111111111111111111111111111111111111111
+  // = 2097151*(2^32) + (2^32 - 1).
+  // So it's safe until hi <= 2097151. See
+  // <http://mdn.io/issafeinteger>, <https://stackoverflow.com/q/307179>
+  // for details.
+  assert(noAssert || hi <= 2097151, "Unsafe integer");
+  return hi * 4294967296 + lo;
+};
+
+var readTimestamp64BE = exports.readTimestamp64BE = function(buf, offset) {
+  offset = offset || 0;
+  var timeHi = buf.readUInt32BE(offset);
+  var timeLo = buf.readUInt32BE(offset + 4);
+  // JavaScript's Date object can't work with timestamps higher than
+  // 8640000000000 (~2^43, ~275760 year). Hope JavaScript will support
+  // 64-bit numbers up to this date.
+  assert(timeHi <= 2011, "Time is too high");
+  assert(timeHi !== 2011 || timeLo <= 2820767744, "Time is too high");
+  return timeHi * 4294967296 + timeLo;
+};
+
+exports.readTime64BE = function(buf, offset) {
+  var timestamp = readTimestamp64BE(buf, offset);
+  return new Date(timestamp * 1000);
+};
+
+exports.writeUInt64BE = function(buf, value, offset, noAssert) {
+  buf = buf || new Buffer(8);
+  offset = offset || 0;
+  assert(noAssert || value <= MAX_SAFE_INTEGER, "Unsafe integer");
+  buf.writeUInt32BE(Math.floor(value / 4294967296), offset, noAssert);
+  buf.writeUInt32BE(value % 4294967296, offset + 4, noAssert);
+  return buf;
+};
+var writeUInt64BE = exports.writeUInt64BE;
+
+exports.writeTime64BE = function(buf, time, offset, noAssert) {
+  var timestamp = Math.floor(time.getTime() / 1000);
+  return writeUInt64BE(buf, timestamp, offset, noAssert);
+};

src/pow.h

@@ -1,8 +1,8 @@
 #ifndef BITCHAN_BITMESSAGE_POW_H_
 #define BITCHAN_BITMESSAGE_POW_H_
 
-static const int MAX_POOL_SIZE = 1024;
-static const int HASH_SIZE = 64;
+static const size_t MAX_POOL_SIZE = 1024;
+static const size_t HASH_SIZE = 64;
 
 int pow(size_t pool_size,
         uint64_t target,

test.js

@@ -16,6 +16,8 @@ var encrypted = structs.encrypted;
 var messageEncodings = structs.messageEncodings;
 var serviceFeatures = structs.serviceFeatures;
 var pubkeyFeatures = structs.pubkeyFeatures;
+var messages = bitmessage.messages;
+var version = messages.version;
 var WIF = bitmessage.WIF;
 var POW = bitmessage.POW;
 var Address = bitmessage.Address;
@@ -72,6 +74,10 @@ describe("Common structures", function() {
       expect(res.command).to.equal("");
     });
 
+    it("should throw when decoding message with truncated payload", function() {
+      expect(message.decode.bind(null, Buffer("e9beb4d97465737400000000000000000000000770b33ce97061796c6f61", "hex"))).to.throw(Error);
+    });
+
     it("should encode", function() {
       expect(message.encode({command: "test", payload: Buffer("payload")}).toString("hex")).to.equal("e9beb4d97465737400000000000000000000000770b33ce97061796c6f6164");
     });
@@ -275,6 +281,28 @@ describe("Common structures", function() {
   });
 });
 
+describe("Message types", function() {
+  describe("version", function() {
+    it("should encode and decode", function() {
+      var res = version.decode(version.encode({
+        remoteHost: "1.2.3.4",
+        remotePort: 48444,
+        port: 8444,
+      }));
+      expect(res.version).to.equal(3);
+      expect(res.services).to.deep.equal([serviceFeatures.NODE_NETWORK]);
+      expect(res.time).to.be.instanceof(Date);
+      expect(res.remoteHost).to.equal("1.2.3.4");
+      expect(res.remotePort).to.equal(48444);
+      expect(res.port).to.equal(8444);
+      expect(bufferEqual(res.nonce, version.NONCE)).to.be.true;
+      expect(res.software).to.deep.equal(UserAgent.SELF);
+      expect(res.streamNumbers).to.deep.equal([1]);
+      expect(res.length).to.equal(101);
+    });
+  });
+});
+
 describe("WIF", function() {
   var wifSign = "5JgQ79vTBusc61xYPtUEHYQ38AXKdDZgQ5rFp7Cbb4ZjXUKFZEV";
   var wifEnc = "5K2aL8cnsEWHwHfHnUrPo8QdYyRfoYUBmhAnWY5GTpDLbeyusnE";