tls_client_hello: JavaScript parsing library

KS implementation details

License: MIT

References

This page hosts a formal specification of tls_client_hello using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for JavaScript generated by Kaitai Struct depends on the JavaScript runtime library. You have to install it before you can parse data.

The JavaScript runtime library is available at npm:

npm install kaitai-struct

Code

See the usage examples in the JavaScript notes.

Parse structure from an ArrayBuffer:

var arrayBuffer = ...;
var data = new TlsClientHello(new KaitaiStream(arrayBuffer));

After that, one can get various attributes from the structure by accessing fields or properties like:

data.version // => get version

JavaScript source code to parse tls_client_hello

TlsClientHello.js

// This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

(function (root, factory) {
  if (typeof define === 'function' && define.amd) {
    define(['kaitai-struct/KaitaiStream'], factory);
  } else if (typeof module === 'object' && module.exports) {
    module.exports = factory(require('kaitai-struct/KaitaiStream'));
  } else {
    root.TlsClientHello = factory(root.KaitaiStream);
  }
}(this, function (KaitaiStream) {
var TlsClientHello = (function() {
  function TlsClientHello(_io, _parent, _root) {
    this._io = _io;
    this._parent = _parent;
    this._root = _root || this;

    this._read();
  }
  TlsClientHello.prototype._read = function() {
    this.version = new Version(this._io, this, this._root);
    this.random = new Random(this._io, this, this._root);
    this.sessionId = new SessionId(this._io, this, this._root);
    this.cipherSuites = new CipherSuites(this._io, this, this._root);
    this.compressionMethods = new CompressionMethods(this._io, this, this._root);
    if (this._io.isEof() == false) {
      this.extensions = new Extensions(this._io, this, this._root);
    }
  }

  var ServerName = TlsClientHello.ServerName = (function() {
    function ServerName(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    ServerName.prototype._read = function() {
      this.nameType = this._io.readU1();
      this.length = this._io.readU2be();
      this.hostName = this._io.readBytes(this.length);
    }

    return ServerName;
  })();

  var Random = TlsClientHello.Random = (function() {
    function Random(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Random.prototype._read = function() {
      this.gmtUnixTime = this._io.readU4be();
      this.random = this._io.readBytes(28);
    }

    return Random;
  })();

  var SessionId = TlsClientHello.SessionId = (function() {
    function SessionId(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    SessionId.prototype._read = function() {
      this.len = this._io.readU1();
      this.sid = this._io.readBytes(this.len);
    }

    return SessionId;
  })();

  var Sni = TlsClientHello.Sni = (function() {
    function Sni(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Sni.prototype._read = function() {
      this.listLength = this._io.readU2be();
      this.serverNames = [];
      var i = 0;
      while (!this._io.isEof()) {
        this.serverNames.push(new ServerName(this._io, this, this._root));
        i++;
      }
    }

    return Sni;
  })();

  var CipherSuites = TlsClientHello.CipherSuites = (function() {
    function CipherSuites(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    CipherSuites.prototype._read = function() {
      this.len = this._io.readU2be();
      this.cipherSuites = new Array(Math.floor(this.len / 2));
      for (var i = 0; i < Math.floor(this.len / 2); i++) {
        this.cipherSuites[i] = this._io.readU2be();
      }
    }

    return CipherSuites;
  })();

  var CompressionMethods = TlsClientHello.CompressionMethods = (function() {
    function CompressionMethods(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    CompressionMethods.prototype._read = function() {
      this.len = this._io.readU1();
      this.compressionMethods = this._io.readBytes(this.len);
    }

    return CompressionMethods;
  })();

  var Alpn = TlsClientHello.Alpn = (function() {
    function Alpn(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Alpn.prototype._read = function() {
      this.extLen = this._io.readU2be();
      this.alpnProtocols = [];
      var i = 0;
      while (!this._io.isEof()) {
        this.alpnProtocols.push(new Protocol(this._io, this, this._root));
        i++;
      }
    }

    return Alpn;
  })();

  var Extensions = TlsClientHello.Extensions = (function() {
    function Extensions(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Extensions.prototype._read = function() {
      this.len = this._io.readU2be();
      this.extensions = [];
      var i = 0;
      while (!this._io.isEof()) {
        this.extensions.push(new Extension(this._io, this, this._root));
        i++;
      }
    }

    return Extensions;
  })();

  var Version = TlsClientHello.Version = (function() {
    function Version(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Version.prototype._read = function() {
      this.major = this._io.readU1();
      this.minor = this._io.readU1();
    }

    return Version;
  })();

  var Protocol = TlsClientHello.Protocol = (function() {
    function Protocol(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Protocol.prototype._read = function() {
      this.strlen = this._io.readU1();
      this.name = this._io.readBytes(this.strlen);
    }

    return Protocol;
  })();

  var Extension = TlsClientHello.Extension = (function() {
    function Extension(_io, _parent, _root) {
      this._io = _io;
      this._parent = _parent;
      this._root = _root || this;

      this._read();
    }
    Extension.prototype._read = function() {
      this.type = this._io.readU2be();
      this.len = this._io.readU2be();
      switch (this.type) {
      case 0:
        this._raw_body = this._io.readBytes(this.len);
        var _io__raw_body = new KaitaiStream(this._raw_body);
        this.body = new Sni(_io__raw_body, this, this._root);
        break;
      case 16:
        this._raw_body = this._io.readBytes(this.len);
        var _io__raw_body = new KaitaiStream(this._raw_body);
        this.body = new Alpn(_io__raw_body, this, this._root);
        break;
      default:
        this.body = this._io.readBytes(this.len);
        break;
      }
    }

    return Extension;
  })();

  return TlsClientHello;
})();
return TlsClientHello;
}));