From 530a9a0c698d03dc6862e5a7f0b3f9196860ed40 Mon Sep 17 00:00:00 2001
From: Michal Kolodziej <softcushiontorture@gmail.com>
Date: Wed, 24 Apr 2013 10:46:43 +0200
Subject: [PATCH] Changed mpi interface to a more sane variant - openpgp
 methods MUST return openpgp_type_mpi, using BigIntegers is prohibited as
 otherwise the wrapper has no point.

---
 resources/openpgp.js                          | 380 +++++++++---------
 resources/openpgp.min.js                      |  18 +-
 src/ciphers/openpgp.crypto.js                 |  97 +++--
 .../public_key_encrypted_session_key.js       |  39 +-
 src/type/{openpgp.type.mpi.js => mpi.js}      | 106 ++---
 src/type/openpgp.type.keyid.js                |   4 +
 test/general/packet.js                        |  20 +-
 7 files changed, 315 insertions(+), 349 deletions(-)
 rename src/type/{openpgp.type.mpi.js => mpi.js} (61%)

diff --git a/resources/openpgp.js b/resources/openpgp.js
index cc7c5046..92261658 100644
--- a/resources/openpgp.js
+++ b/resources/openpgp.js
@@ -3670,25 +3670,33 @@ function normal_cfb_decrypt(blockcipherencryptfn, block_size, key, ciphertext, i
  * if elgamal encryption an array of two openpgp_type_mpi is returned; otherwise null
  */
 function openpgp_crypto_asymetricEncrypt(algo, publicMPIs, data) {
-	switch(algo) {
-	case 1: // RSA (Encrypt or Sign) [HAC]
-	case 2: // RSA Encrypt-Only [HAC]
-	case 3: // RSA Sign-Only [HAC]
-		var rsa = new RSA();
-		var n = publicMPIs[0].toBigInteger();
-		var e = publicMPIs[1].toBigInteger();
-		var m = data.toBigInteger();
-		return [rsa.encrypt(m,e,n)];
-	case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
-		var elgamal = new Elgamal();
-		var p = publicMPIs[0].toBigInteger();
-		var g = publicMPIs[1].toBigInteger();
-		var y = publicMPIs[2].toBigInteger();
-		var m = data.toBigInteger();
-		return elgamal.encrypt(m,g,p,y);
-	default:
-		return null;
-	}
+	var result = (function() {
+		switch(algo) {
+		case 1: // RSA (Encrypt or Sign) [HAC]
+		case 2: // RSA Encrypt-Only [HAC]
+		case 3: // RSA Sign-Only [HAC]
+			var rsa = new RSA();
+			var n = publicMPIs[0].toBigInteger();
+			var e = publicMPIs[1].toBigInteger();
+			var m = data.toBigInteger();
+			return [rsa.encrypt(m,e,n)];
+		case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
+			var elgamal = new Elgamal();
+			var p = publicMPIs[0].toBigInteger();
+			var g = publicMPIs[1].toBigInteger();
+			var y = publicMPIs[2].toBigInteger();
+			var m = data.toBigInteger();
+			return elgamal.encrypt(m,g,p,y);
+		default:
+			return [];
+		}
+	})();
+
+	return result.map(function(bn) {
+		var mpi = new openpgp_type_mpi();
+		mpi.fromBigInteger(bn);
+		return mpi;
+	});
 }
 
 /**
@@ -3700,32 +3708,37 @@ function openpgp_crypto_asymetricEncrypt(algo, publicMPIs, data) {
  * @param {openpgp_type_mpi[]} secretMPIs Algorithm dependent multiprecision integers 
  * of the private key used
  * @param {openpgp_type_mpi} data Data to be encrypted as MPI
- * @return {BigInteger} returns a big integer containing the decrypted data; otherwise null
+ * @return {openpgp_type_mpi} returns a big integer containing the decrypted data; otherwise null
  */
 
 function openpgp_crypto_asymetricDecrypt(algo, publicMPIs, secretMPIs, dataMPIs) {
-	switch(algo) {
-	case 1: // RSA (Encrypt or Sign) [HAC]  
-	case 2: // RSA Encrypt-Only [HAC]
-	case 3: // RSA Sign-Only [HAC]
-		var rsa = new RSA();
-		var d = secretMPIs[0].toBigInteger();
-		var p = secretMPIs[1].toBigInteger();
-		var q = secretMPIs[2].toBigInteger();
-		var u = secretMPIs[3].toBigInteger();
-		var m = dataMPIs[0].toBigInteger();
-		return rsa.decrypt(m, d, p, q, u);
-	case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
-		var elgamal = new Elgamal();
-		var x = secretMPIs[0].toBigInteger();
-		var c1 = dataMPIs[0].toBigInteger();
-		var c2 = dataMPIs[1].toBigInteger();
-		var p = publicMPIs[0].toBigInteger();
-		return elgamal.decrypt(c1,c2,p,x);
-	default:
-		return null;
-	}
-	
+	var bn = (function() {
+		switch(algo) {
+		case 1: // RSA (Encrypt or Sign) [HAC]  
+		case 2: // RSA Encrypt-Only [HAC]
+		case 3: // RSA Sign-Only [HAC]
+			var rsa = new RSA();
+			var d = secretMPIs[0].toBigInteger();
+			var p = secretMPIs[1].toBigInteger();
+			var q = secretMPIs[2].toBigInteger();
+			var u = secretMPIs[3].toBigInteger();
+			var m = dataMPIs[0].toBigInteger();
+			return rsa.decrypt(m, d, p, q, u);
+		case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
+			var elgamal = new Elgamal();
+			var x = secretMPIs[0].toBigInteger();
+			var c1 = dataMPIs[0].toBigInteger();
+			var c2 = dataMPIs[1].toBigInteger();
+			var p = publicMPIs[0].toBigInteger();
+			return elgamal.decrypt(c1,c2,p,x);
+		default:
+			return null;
+		}
+	})();
+
+	var result = new openpgp_type_mpi();
+	result.fromBigInteger(bn);
+	return result;
 }
 
 /**
@@ -12509,9 +12522,7 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		}
 
 		this.version = bytes[0].charCodeAt();
-
 		this.public_key_id.read_packet(bytes, 1);
-
 		this.public_key_algorithm = bytes[9].charCodeAt();
 
 		var i = 10;
@@ -12522,16 +12533,15 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		case openpgp.publickey.rsa_encrypt_sign:
 			this.encrypted = [];
 			this.encrypted[0] = new openpgp_type_mpi();
-			this.encrypted[0].read(bytes, i, bytes.length - i);
+			this.encrypted[0].read(bytes.substr(i));
 			break;
 
 		case openpgp.publickey.elgamal:
 			this.encrypted = [];
 			this.encrypted[0] = new openpgp_type_mpi();
-			this.encrypted[0].read(bytes, i, bytes.length - i);
-			i += this.encrypted[0].packetLength;
+			i += this.encrypted[0].read(bytes.substr(i));
 			this.encrypted[1] = new openpgp_type_mpi();
-			this.encrypted[1].read(bytes, i, bytes.length - i);
+			this.encrypted[1].read(bytes.substr(i));
 			break;
 
 		default:
@@ -12567,7 +12577,7 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		result += String.fromCharCode(this.public_key_algorithm);
 
 		for ( var i = 0; i < this.encrypted.length; i++) {
-			result += this.encrypted[i].toBin();
+			result += this.encrypted[i].write()
 		}
 
 		return result;
@@ -12582,20 +12592,14 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		data += String.fromCharCode((checksum) & 0xFF);
 
 		var mpi = new openpgp_type_mpi();
+		mpi.fromBytes(openpgp_encoding_eme_pkcs1_encode(
+			data,
+			public_key_mpi[0].byteLength()));
 
-		var encrypted = openpgp_crypto_asymetricEncrypt(
+		this.encrypted = openpgp_crypto_asymetricEncrypt(
 			this.public_key_algorithm, 
 			public_key_mpi,
-			mpi.create(openpgp_encoding_eme_pkcs1_encode(data,
-					public_key_mpi[0].mpiByteLength)));
-
-		// TODO: fix this - make openpgp_crypto_ interfaces uniform
-		this.encrypted = encrypted.map(function(k) {
-				var mpi = new openpgp_type_mpi;
-				var b = k.toMPI();
-				mpi.read(b, 0, b.length);
-				return mpi;
-			});
+			mpi);
 	}
 
 	/**
@@ -12613,16 +12617,16 @@ function openpgp_packet_public_key_encrypted_session_key() {
 				this.public_key_algorithm,
 				public_key_mpi,
 				private_key_mpi,
-				this.encrypted).toMPI();
+				this.encrypted).toBytes();
 
-		var checksum = ((result.charCodeAt(result.length - 2) << 8) + result
-				.charCodeAt(result.length - 1));
+		var checksum = ((result.charCodeAt(result.length - 2) << 8) 
+			+ result.charCodeAt(result.length - 1));
 
 		var decoded = openpgp_encoding_eme_pkcs1_decode(
-			result.substring(2, result.length - 2), 
-			public_key_mpi[0].getByteLength());
+			result,
+			public_key_mpi[0].byteLength());
 
-		var key = decoded.substring(1);
+		var key = decoded.substring(1, decoded.length - 2);
 
 		if(checksum != util.calc_checksum(key)) {
 			util.print_error("Checksum mismatch");
@@ -13005,6 +13009,111 @@ function openpgp_packet_symmetrically_encrypted() {
 // License along with this library; if not, write to the Free Software
 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
+// Hint: We hold our MPIs as an array of octets in big endian format preceeding a two
+// octet scalar: MPI: [a,b,c,d,e,f]
+// - MPI size: (a << 8) | b 
+// - MPI = c | d << 8 | e << ((MPI.length -2)*8) | f ((MPI.length -2)*8)
+
+/**
+ * @class
+ * @classdescImplementation of type MPI (RFC4880 3.2)
+ * Multiprecision integers (also called MPIs) are unsigned integers used
+ * to hold large integers such as the ones used in cryptographic
+ * calculations.
+ * An MPI consists of two pieces: a two-octet scalar that is the length
+ * of the MPI in bits followed by a string of octets that contain the
+ * actual integer.
+ */
+function openpgp_type_mpi() {
+	/** An implementation dependent integer */
+	this.data = null;
+
+	/**
+	 * Parsing function for a mpi (RFC 4880 3.2).
+	 * @param {String} input Payload of mpi data
+	 * @param {Integer} position Position to start reading from the input 
+	 * string
+	 * @param {Integer} len Length of the packet or the remaining length of 
+	 * input at position
+	 * @return {openpgp_type_mpi} Object representation
+	 */
+	this.read = function(bytes) {
+		var bits = (bytes[0].charCodeAt() << 8) | bytes[1].charCodeAt();
+		
+		// Additional rules:
+		//
+		//    The size of an MPI is ((MPI.length + 7) / 8) + 2 octets.
+		//
+		//    The length field of an MPI describes the length starting from its
+		//	  most significant non-zero bit.  Thus, the MPI [00 02 01] is not
+		//    formed correctly.  It should be [00 01 01].
+
+		// TODO: Verification of this size method! This size calculation as
+		// 		 specified above is not applicable in JavaScript
+		var bytelen = Math.ceil(bits / 8);
+		
+		var raw = bytes.substr(2, bytelen);
+		this.fromBytes(raw);
+
+		return 2 + bytelen;
+	}
+
+	this.fromBytes = function(bytes) {
+		this.data = new BigInteger(util.hexstrdump(bytes), 16); 
+	}
+
+	this.toBytes = function() {
+		return this.write().substr(2);
+	}
+
+	this.byteLength = function() {
+		return this.toBytes().length;
+	}
+
+	/**
+	 * Converts the mpi object to a string as specified in RFC4880 3.2
+	 * @return {String} mpi Byte representation
+	 */
+	this.write = function() {
+		return this.data.toMPI();
+	}
+
+	this.toBigInteger = function() {
+		return this.data.clone();
+	}
+
+	this.fromBigInteger = function(bn) {
+		this.data = bn.clone();
+	}
+
+	/**
+	 * Generates debug output (pretty print)
+	 * @return {String} String which gives some information about the mpi
+	 */
+	this.toString = function() {
+		var r = "    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x";
+		r+=util.hexstrdump(this.MPI);
+		return r+'\n';
+	}
+}
+
+// GPG4Browsers - An OpenPGP implementation in javascript
+// Copyright (C) 2011 Recurity Labs GmbH
+// 
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// 
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+// 
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
 /**
  * @class
  * @classdesc Implementation of type key id (RFC4880 3.3)
@@ -13014,6 +13123,10 @@ function openpgp_packet_symmetrically_encrypted() {
    formed.
  */
 function openpgp_type_keyid() {
+	var bytes = '';
+
+	for(var i = 0; i < 8; i++)
+		bytes += String.fromCharCode(0);
 	/**
 	 * Parsing method for a key id
 	 * @param {String} input Input to read the key id from 
@@ -13054,141 +13167,6 @@ function openpgp_type_keyid() {
 // License along with this library; if not, write to the Free Software
 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 
-// Hint: We hold our MPIs as an array of octets in big endian format preceeding a two
-// octet scalar: MPI: [a,b,c,d,e,f]
-// - MPI size: (a << 8) | b 
-// - MPI = c | d << 8 | e << ((MPI.length -2)*8) | f ((MPI.length -2)*8)
-
-/**
- * @class
- * @classdescImplementation of type MPI (RFC4880 3.2)
- * Multiprecision integers (also called MPIs) are unsigned integers used
- * to hold large integers such as the ones used in cryptographic
- * calculations.
- * An MPI consists of two pieces: a two-octet scalar that is the length
- * of the MPI in bits followed by a string of octets that contain the
- * actual integer.
- */
-function openpgp_type_mpi() {
-	this.MPI = null;
-	this.mpiBitLength = null;
-	this.mpiByteLength = null;
-	this.data = null;
-	/**
-	 * Parsing function for a mpi (RFC 4880 3.2).
-	 * @param {String} input Payload of mpi data
-	 * @param {Integer} position Position to start reading from the input 
-	 * string
-	 * @param {Integer} len Length of the packet or the remaining length of 
-	 * input at position
-	 * @return {openpgp_type_mpi} Object representation
-	 */
-	function read(input, position, len) {
-		var mypos = position;
-		
-		this.mpiBitLength = (input[mypos++].charCodeAt() << 8) | input[mypos++].charCodeAt();
-		
-		// Additional rules:
-		//
-		//    The size of an MPI is ((MPI.length + 7) / 8) + 2 octets.
-		//
-		//    The length field of an MPI describes the length starting from its
-		//	  most significant non-zero bit.  Thus, the MPI [00 02 01] is not
-		//    formed correctly.  It should be [00 01 01].
-
-		// TODO: Verification of this size method! This size calculation as
-		// 		 specified above is not applicable in JavaScript
-		this.mpiByteLength = (this.mpiBitLength - (this.mpiBitLength % 8)) / 8;
-		if (this.mpiBitLength % 8 != 0)
-			this.mpiByteLength++;
-		
-		this.MPI = input.substring(mypos,mypos+this.mpiByteLength);
-		this.data = input.substring(position, position+2+this.mpiByteLength);
-		this.packetLength = this.mpiByteLength +2;
-		return this;
-	}
-	
-	/**
-	 * Generates debug output (pretty print)
-	 * @return {String} String which gives some information about the mpi
-	 */
-	function toString() {
-		var r = "    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x";
-		r+=util.hexstrdump(this.MPI);
-		return r+'\n';
-	}
-	
-	/**
-	 * Converts the mpi to an BigInteger object
-	 * @return {BigInteger}
-	 */
-	function getBigInteger() {
-		return new BigInteger(util.hexstrdump(this.MPI),16); 
-	}
-
-	
-	function getBits(num) {
-		for (var i = 0; i < 9; i++)
-		if (num >> i == 0)
-		return i;
-	}
-	
-	/**
-	 * Gets the length of the mpi in bytes
-	 * @return {Integer} Mpi byte length
-	 */
-	function getByteLength() {
-		return this.mpiByteLength;
-	}
-	
-	/**
-	 * Creates an mpi from the specified string
-	 * @param {String} data Data to read the mpi from
-	 * @return {openpgp_type_mpi} 
-	 */
-	function create(data) {
-		this.MPI = data;
-		this.mpiBitLength = (data.length -1) *8 + getBits(data.charCodeAt(0));
-		this.mpiByteLength = data.length;
-		return this;
-	}
-	
-	/**
-	 * Converts the mpi object to a string as specified in RFC4880 3.2
-	 * @return {String} mpi Byte representation
-	 */
-	function toBin() {
-		var result = String.fromCharCode((this.mpiBitLength >> 8) & 0xFF);
-		result += String.fromCharCode(this.mpiBitLength & 0xFF);
-		result += this.MPI;
-		return result;
-	}
-	
-	this.read = read;
-	this.toBigInteger = getBigInteger;
-	this.toString = toString;
-	this.create = create;
-	this.toBin = toBin;
-	this.getByteLength = getByteLength;
-}
-
-// GPG4Browsers - An OpenPGP implementation in javascript
-// Copyright (C) 2011 Recurity Labs GmbH
-// 
-// This library is free software; you can redistribute it and/or
-// modify it under the terms of the GNU Lesser General Public
-// License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// 
-// This library is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public
-// License along with this library; if not, write to the Free Software
-// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
-
 /**
  * @class
  * @classdesc Implementation of the String-to-key specifier (RFC4880 3.7)
diff --git a/resources/openpgp.min.js b/resources/openpgp.min.js
index 34b9e4d4..778c952c 100644
--- a/resources/openpgp.min.js
+++ b/resources/openpgp.min.js
@@ -107,8 +107,8 @@ function openpgp_cfb_decrypt(b,a,c,d,e){util.print_debug("resync:"+e);var f=Arra
 k.join("");if(e){for(h=0;h<a;h++)f[h]=d.charCodeAt(h+2);j=a+2}else{for(h=0;h<a;h++)f[h]=d.charCodeAt(h);j=a}for(;j<d.length;j+=a){g=b(f,c);for(h=0;h<a&&h+j<d.length;h++)f[h]=d.charCodeAt(j+h),k.push(String.fromCharCode(g[h]^f[h]))}return k.join("")}
 function normal_cfb_encrypt(b,a,c,d,e){for(var f="",f="",g=0,h=[],j=[],f=e.substring(0,a);d.length>a*g;){for(var e=b(f,c),f=d.substring(g*a,g*a+a),k=0;k<f.length;k++)j.push(String.fromCharCode(f.charCodeAt(k)^e[k]));f=j.join("");j=[];h.push(f);g++}return h.join("")}
 function normal_cfb_decrypt(b,a,c,d,e){var f="",g=0,h=[];if(null==e)for(e=0;e<a;e++)f+=String.fromCharCode(0);else f=e.substring(0,a);for(;d.length>a*g;){for(var j=b(f,c),f=d.substring(g*a+0,g*a+a+0),e=0;e<f.length;e++)h.push(String.fromCharCode(f.charCodeAt(e)^j[e]));g++}return h.join("")}
-function openpgp_crypto_asymetricEncrypt(b,a,c){switch(b){case 1:case 2:case 3:var b=new RSA,d=a[0].toBigInteger(),a=a[1].toBigInteger(),c=c.toBigInteger();return[b.encrypt(c,a,d)];case 16:var b=new Elgamal,d=a[0].toBigInteger(),e=a[1].toBigInteger(),a=a[2].toBigInteger(),c=c.toBigInteger();return b.encrypt(c,e,d,a);default:return null}}
-function openpgp_crypto_asymetricDecrypt(b,a,c,d){switch(b){case 1:case 2:case 3:var b=new RSA,e=c[0].toBigInteger(),a=c[1].toBigInteger(),f=c[2].toBigInteger(),c=c[3].toBigInteger(),d=d[0].toBigInteger();return b.decrypt(d,e,a,f,c);case 16:return b=new Elgamal,c=c[0].toBigInteger(),e=d[0].toBigInteger(),d=d[1].toBigInteger(),a=a[0].toBigInteger(),b.decrypt(e,d,a,c);default:return null}}
+function openpgp_crypto_asymetricEncrypt(b,a,c){return function(){switch(b){case 1:case 2:case 3:var d=new RSA,e=a[0].toBigInteger(),f=a[1].toBigInteger(),g=c.toBigInteger();return[d.encrypt(g,f,e)];case 16:var d=new Elgamal,e=a[0].toBigInteger(),f=a[1].toBigInteger(),h=a[2].toBigInteger(),g=c.toBigInteger();return d.encrypt(g,f,e,h);default:return[]}}().map(function(a){var b=new openpgp_type_mpi;b.fromBigInteger(a);return b})}
+function openpgp_crypto_asymetricDecrypt(b,a,c,d){var e=function(){switch(b){case 1:case 2:case 3:var e=new RSA,f=c[0].toBigInteger(),j=c[1].toBigInteger(),k=c[2].toBigInteger(),l=c[3].toBigInteger(),m=d[0].toBigInteger();return e.decrypt(m,f,j,k,l);case 16:return e=new Elgamal,f=c[0].toBigInteger(),k=d[0].toBigInteger(),l=d[1].toBigInteger(),j=a[0].toBigInteger(),e.decrypt(k,l,j,f);default:return null}}(),f=new openpgp_type_mpi;f.fromBigInteger(e);return f}
 function openpgp_crypto_getPrefixRandom(b){switch(b){case 2:case 3:case 4:return openpgp_crypto_getRandomBytes(8);case 7:case 8:case 9:case 10:return openpgp_crypto_getRandomBytes(16);default:return null}}
 function openpgp_crypto_MDCSystemBytes(b,a,c){util.print_debug_hexstr_dump("openpgp_crypto_symmetricDecrypt:\nencrypteddata:",c);switch(b){case 0:return c;case 2:return openpgp_cfb_mdc(desede,8,a,c,openpgp_cfb);case 3:return openpgp_cfb_mdc(cast5_encrypt,8,a,c);case 4:return openpgp_cfb_mdc(BFencrypt,8,a,c);case 7:case 8:case 9:return openpgp_cfb_mdc(AESencrypt,16,keyExpansion(a),c);case 10:return openpgp_cfb_mdc(TFencrypt,16,a,c);case 1:util.print_error(""+(1==b?"IDEA Algorithm not implemented":
 "Twofish Algorithm not implemented"))}return null}function openpgp_crypto_generateSessionKey(b){return openpgp_crypto_getRandomBytes(openpgp_crypto_getKeyLength(b))}function openpgp_crypto_getKeyLength(b){switch(b){case 2:case 8:return 24;case 3:case 4:case 7:return 16;case 9:case 10:return 32}return null}
@@ -444,10 +444,10 @@ g+j);d+=j;g+=j;break}j=g}else b++,d=a[b++].charCodeAt()<<24|a[b++].charCodeAt()<
 return{packet:k,offset:b+d}};this.type={reserved:0,public_key_encrypted_session_key:1,signature:2,sym_encrypted_session_key:3,one_pass_signature:4,secret_key:5,public_key:6,secret_subkey:7,compressed:8,symmetrically_encrypted:9,marker:10,literal:11,trust:12,userid:13,public_subkey:14,user_attribute:17,sym_encrypted_integrity_protected:18,modification_detection_code:19}}var openpgp_packet=new _openpgp_packet;
 function openpgp_packetlist(){this.length=0;this.read=function(b){this.packets=[];for(var a=0;a<b.length;){var c=openpgp_packet.read_packet(b,a,b.length-a),a=c.offset;this.push(c.packet)}};this.write=function(){for(var b="",a=0;a<this.length;a++)var c=this[a].write(),b=b+openpgp_packet.write_packet_header(this[a].tag,c.length),b=b+c;return b};this.push=function(b){this[this.length]=b;this.length++}}
 function openpgp_packet_public_key_encrypted_session_key(){this.tag=1;this.version=3;this.public_key_id=new openpgp_type_keyid;this.public_key_algorithm=openpgp.publickey.rsa_encrypt_sign;this.symmetric_key=null;this.symmetric_algorithm=openpgp.symmetric.plaintext;this.encrypted=[];this.read=function(b){if(10>b.length)return util.print_error("openpgp.packet.encryptedsessionkey.js\ninvalid length"),null;this.version=b[0].charCodeAt();this.public_key_id.read_packet(b,1);this.public_key_algorithm=b[9].charCodeAt();
-var a=10;switch(this.public_key_algorithm){case openpgp.publickey.rsa_encrypt:case openpgp.publickey.rsa_encrypt_sign:this.encrypted=[];this.encrypted[0]=new openpgp_type_mpi;this.encrypted[0].read(b,a,b.length-a);break;case openpgp.publickey.elgamal:this.encrypted=[];this.encrypted[0]=new openpgp_type_mpi;this.encrypted[0].read(b,a,b.length-a);a+=this.encrypted[0].packetLength;this.encrypted[1]=new openpgp_type_mpi;this.encrypted[1].read(b,a,b.length-a);break;default:util.print_error("openpgp.packet.encryptedsessionkey.js\nunknown public key packet algorithm type "+
-this.public_key_algorithm)}};this.write=function(){for(var b=String.fromCharCode(this.version),b=b+this.public_key_id.bytes,b=b+String.fromCharCode(this.public_key_algorithm),a=0;a<this.encrypted.length;a++)b+=this.encrypted[a].toBin();return b};this.encrypt=function(b){var a=String.fromCharCode(this.symmetric_algorithm),a=a+this.symmetric_key,c=util.calc_checksum(this.symmetric_key),a=a+String.fromCharCode(c>>8&255),a=a+String.fromCharCode(c&255),c=new openpgp_type_mpi;this.encrypted=openpgp_crypto_asymetricEncrypt(this.public_key_algorithm,
-b,c.create(openpgp_encoding_eme_pkcs1_encode(a,b[0].mpiByteLength))).map(function(a){var b=new openpgp_type_mpi,a=a.toMPI();b.read(a,0,a.length);return b})};this.decrypt=function(b,a){var c=openpgp_crypto_asymetricDecrypt(this.public_key_algorithm,b,a,this.encrypted).toMPI(),d=(c.charCodeAt(c.length-2)<<8)+c.charCodeAt(c.length-1),c=openpgp_encoding_eme_pkcs1_decode(c.substring(2,c.length-2),b[0].getByteLength()),e=c.substring(1);d!=util.calc_checksum(e)?util.print_error("Checksum mismatch"):(this.symmetric_key=
-e,this.symmetric_algorithm=c.charCodeAt(0))};this.toString=function(){for(var b="5.1.  Public-Key Encrypted Session Key Packets (Tag 1)\n    KeyId:  "+this.keyId.toString()+"\n    length: "+this.packetLength+"\n    version:"+this.version+"\n    pubAlgUs:"+this.publicKeyAlgorithmUsed+"\n",a=0;a<this.encrypted.length;a++)b+=this.encrypted[a].toString();return b}}
+var a=10;switch(this.public_key_algorithm){case openpgp.publickey.rsa_encrypt:case openpgp.publickey.rsa_encrypt_sign:this.encrypted=[];this.encrypted[0]=new openpgp_type_mpi;this.encrypted[0].read(b.substr(a));break;case openpgp.publickey.elgamal:this.encrypted=[];this.encrypted[0]=new openpgp_type_mpi;a+=this.encrypted[0].read(b.substr(a));this.encrypted[1]=new openpgp_type_mpi;this.encrypted[1].read(b.substr(a));break;default:util.print_error("openpgp.packet.encryptedsessionkey.js\nunknown public key packet algorithm type "+
+this.public_key_algorithm)}};this.write=function(){for(var b=String.fromCharCode(this.version),b=b+this.public_key_id.bytes,b=b+String.fromCharCode(this.public_key_algorithm),a=0;a<this.encrypted.length;a++)b+=this.encrypted[a].write();return b};this.encrypt=function(b){var a=String.fromCharCode(this.symmetric_algorithm),a=a+this.symmetric_key,c=util.calc_checksum(this.symmetric_key),a=a+String.fromCharCode(c>>8&255),a=a+String.fromCharCode(c&255),c=new openpgp_type_mpi;c.fromBytes(openpgp_encoding_eme_pkcs1_encode(a,
+b[0].byteLength()));this.encrypted=openpgp_crypto_asymetricEncrypt(this.public_key_algorithm,b,c)};this.decrypt=function(b,a){var c=openpgp_crypto_asymetricDecrypt(this.public_key_algorithm,b,a,this.encrypted).toBytes(),d=(c.charCodeAt(c.length-2)<<8)+c.charCodeAt(c.length-1),c=openpgp_encoding_eme_pkcs1_decode(c,b[0].byteLength()),e=c.substring(1,c.length-2);d!=util.calc_checksum(e)?util.print_error("Checksum mismatch"):(this.symmetric_key=e,this.symmetric_algorithm=c.charCodeAt(0))};this.toString=
+function(){for(var b="5.1.  Public-Key Encrypted Session Key Packets (Tag 1)\n    KeyId:  "+this.keyId.toString()+"\n    length: "+this.packetLength+"\n    version:"+this.version+"\n    pubAlgUs:"+this.publicKeyAlgorithmUsed+"\n",a=0;a<this.encrypted.length;a++)b+=this.encrypted[a].toString();return b}}
 function openpgp_packet_sym_encrypted_integrity_protected(){this.tag=18;this.version=1;this.encrypted=null;this.modification=!1;this.packets=new openpgp_packetlist;this.read=function(b){this.version=b[0].charCodeAt();if(1!=this.version)return util.print_error("openpgp.packet.encryptedintegrityprotecteddata.js\nunknown encrypted integrity protected data packet version: "+this.version+"hex:"+util.hexstrdump(b)),null;this.encrypted=b.substr(1)};this.write=function(){return String.fromCharCode(this.version)+
 this.encrypted};this.encrypt=function(b,a){var c=this.packets.write(),d=openpgp_crypto_getPrefixRandom(b),e=d+d.charAt(d.length-2)+d.charAt(d.length-1),c=c+String.fromCharCode(211),c=c+String.fromCharCode(20);util.print_debug_hexstr_dump("data to be hashed:",e+c);c+=str_sha1(e+c);util.print_debug_hexstr_dump("hash:",c.substring(c.length-20,c.length));this.encrypted=openpgp_crypto_symmetricEncrypt(d,b,a,c,!1).substring(0,e.length+c.length)};this.decrypt=function(b,a){var c=openpgp_crypto_symmetricDecrypt(b,
 a,this.encrypted,!1);this.hash=str_sha1(openpgp_crypto_MDCSystemBytes(b,a,this.encrypted)+c.substring(0,c.length-20));util.print_debug_hexstr_dump("calc hash = ",this.hash);this.packets.read(c.substr(0,c.length-22));if(this.hash!=c.substr(c.length-20,20))this.packets=null,util.print_error("Decryption stopped: discovered a modification of encrypted data.")};this.toString=function(){var b="";openpgp.config.debug&&(b="    data: Bytes ["+util.hexstrdump(this.encrypted)+"]");return"5.13.  Sym. Encrypted Integrity Protected Data Packet (Tag 18)\n\n    version: "+
@@ -455,9 +455,9 @@ this.version+"\n"+b}}
 function openpgp_packet_sym_encrypted_session_key(){this.tag=3;this.algorithm=this.private_algorithm=openpgp.symmetric.plaintext;this.encrypted=null;this.s2k=new openpgp_type_s2k;this.read=function(b){this.version=b[0].charCodeAt();this.private_algorithm=b[1].charCodeAt();this.s2k.read(b,2);var a=this.s2k.length+2;if(a<b.length)this.encrypted=b.substr(a)};this.decrypt=function(b){var a=openpgp_crypto_getKeyLength(this.private_algorithm),b=this.s2k.produce_key(b,a);null==this.encrypted?(this.key=b,
 this.algorithm=this.private_algorithm):(b=openpgp_crypto_symmetricDecrypt(this.private_algorithm,b,this.encrypted,!0),this.algorithm=b[0].keyCodeAt(),this.key=b.substr(1))};this.toString=function(){return"5.3 Symmetric-Key Encrypted Session Key Packets (Tag 3)\n    KeyId:  "+this.keyId.toString()+"\n    length: "+this.packetLength+"\n    version:"+this.version+"\n    symKeyA:"+this.symmetricKeyAlgorithmUsed+"\n    s2k:    "+this.s2k+"\n"}}
 function openpgp_packet_symmetrically_encrypted(){this.tag=9;this.encrypted=null;this.packets=new openpgp_packetlist;this.read=function(b){this.encrypted=b};this.write=function(){return this.encrypted};this.decrypt=function(b,a){this.packets.read(openpgp_crypto_symmetricDecrypt(b,a,this.encrypted,!0))};this.encrypt=function(b,a){var c=this.packets.write();this.encrypted=openpgp_crypto_symmetricEncrypt(openpgp_crypto_getPrefixRandom(b),b,a,c,!0)};this.toString=function(){return"5.7.  Symmetrically Encrypted Data Packet (Tag 9)\n    Used symmetric algorithm: "+
-this.algorithmType+"\n    encrypted data: Bytes ["+util.hexstrdump(this.encryptedData)+"]\n"}}function openpgp_type_keyid(){this.read_packet=function(b,a){this.bytes=b.substring(a,a+8);return this};this.toString=function(){return util.hexstrdump(this.bytes)}}
-function openpgp_type_mpi(){this.data=this.mpiByteLength=this.mpiBitLength=this.MPI=null;this.read=function(b,a){var c=a;this.mpiBitLength=b[c++].charCodeAt()<<8|b[c++].charCodeAt();this.mpiByteLength=(this.mpiBitLength-this.mpiBitLength%8)/8;0!=this.mpiBitLength%8&&this.mpiByteLength++;this.MPI=b.substring(c,c+this.mpiByteLength);this.data=b.substring(a,a+2+this.mpiByteLength);this.packetLength=this.mpiByteLength+2;return this};this.toBigInteger=function(){return new BigInteger(util.hexstrdump(this.MPI),
-16)};this.toString=function(){var b="    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x",b=b+util.hexstrdump(this.MPI);return b+"\n"};this.create=function(b){this.MPI=b;var a=8*(b.length-1),c;a:for(var d=b.charCodeAt(0),e=0;9>e;e++)if(0==d>>e){c=e;break a}this.mpiBitLength=a+c;this.mpiByteLength=b.length;return this};this.toBin=function(){var b=String.fromCharCode(this.mpiBitLength>>8&255),b=b+String.fromCharCode(this.mpiBitLength&255);return b+=this.MPI};this.getByteLength=function(){return this.mpiByteLength}}
+this.algorithmType+"\n    encrypted data: Bytes ["+util.hexstrdump(this.encryptedData)+"]\n"}}
+function openpgp_type_mpi(){this.data=null;this.read=function(b){var a=b[0].charCodeAt()<<8|b[1].charCodeAt(),a=Math.ceil(a/8);this.fromBytes(b.substr(2,a));return 2+a};this.fromBytes=function(b){this.data=new BigInteger(util.hexstrdump(b),16)};this.toBytes=function(){return this.write().substr(2)};this.byteLength=function(){return this.toBytes().length};this.write=function(){return this.data.toMPI()};this.toBigInteger=function(){return this.data.clone()};this.fromBigInteger=function(b){this.data=
+b.clone()};this.toString=function(){var b="    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x",b=b+util.hexstrdump(this.MPI);return b+"\n"}}function openpgp_type_keyid(){for(var b="",a=0;8>a;a++)b+=String.fromCharCode(0);this.read_packet=function(a,b){this.bytes=a.substring(b,b+8);return this};this.toString=function(){return util.hexstrdump(this.bytes)}}
 function openpgp_type_s2k(){this.read=function(b,a){var c=a;this.type=b[c++].charCodeAt();switch(this.type){case 0:this.hashAlgorithm=b[c++].charCodeAt();this.s2kLength=1;break;case 1:this.hashAlgorithm=b[c++].charCodeAt();this.saltValue=b.substring(c,c+8);c+=8;this.s2kLength=9;break;case 3:this.hashAlgorithm=b[c++].charCodeAt();this.saltValue=b.substring(c,c+8);c+=8;this.EXPBIAS=6;var d=b[c++].charCodeAt();this.count=16+(d&15)<<(d>>4)+this.EXPBIAS;this.s2kLength=10;break;case 101:"GNU"==b.substring(c+
 1,c+4)?(this.hashAlgorithm=b[c++].charCodeAt(),c+=3,d=1E3+b[c++].charCodeAt(),1001==d?(this.type=d,this.s2kLength=5):util.print_error("unknown s2k gnu protection mode! "+this.type)):util.print_error("unknown s2k type! "+this.type);break;default:util.print_error("unknown s2k type! "+this.type)}this.packetLength=c-a;return this};this.write=function(b,a,c,d,e){this.type=b;if(3==this.type)this.saltValue=d,this.hashAlgorithm=a,this.count=16+(e&15)<<(e>>4)+6,this.s2kLength=10;return this.produce_key(c)};
 this.produce_key=function(b,a){var b=util.encode_utf8(b),c;if(0==this.type)c=openpgp_crypto_hashData(this.hashAlgorithm,b);else if(1==this.type)c=openpgp_crypto_hashData(this.hashAlgorithm,this.saltValue+b);else if(3==this.type){c=[];for(c[0]=this.saltValue+b;c.length*(this.saltValue+b).length<this.count;)c.push(this.saltValue+b);c=c.join("");c.length>this.count&&(c=c.substr(0,this.count));c=a&&(24==a||32==a)?openpgp_crypto_hashData(this.hashAlgorithm,c)+openpgp_crypto_hashData(this.hashAlgorithm,
diff --git a/src/ciphers/openpgp.crypto.js b/src/ciphers/openpgp.crypto.js
index ad1deb3b..656ec4c9 100644
--- a/src/ciphers/openpgp.crypto.js
+++ b/src/ciphers/openpgp.crypto.js
@@ -27,25 +27,33 @@
  * if elgamal encryption an array of two openpgp_type_mpi is returned; otherwise null
  */
 function openpgp_crypto_asymetricEncrypt(algo, publicMPIs, data) {
-	switch(algo) {
-	case 1: // RSA (Encrypt or Sign) [HAC]
-	case 2: // RSA Encrypt-Only [HAC]
-	case 3: // RSA Sign-Only [HAC]
-		var rsa = new RSA();
-		var n = publicMPIs[0].toBigInteger();
-		var e = publicMPIs[1].toBigInteger();
-		var m = data.toBigInteger();
-		return [rsa.encrypt(m,e,n)];
-	case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
-		var elgamal = new Elgamal();
-		var p = publicMPIs[0].toBigInteger();
-		var g = publicMPIs[1].toBigInteger();
-		var y = publicMPIs[2].toBigInteger();
-		var m = data.toBigInteger();
-		return elgamal.encrypt(m,g,p,y);
-	default:
-		return null;
-	}
+	var result = (function() {
+		switch(algo) {
+		case 1: // RSA (Encrypt or Sign) [HAC]
+		case 2: // RSA Encrypt-Only [HAC]
+		case 3: // RSA Sign-Only [HAC]
+			var rsa = new RSA();
+			var n = publicMPIs[0].toBigInteger();
+			var e = publicMPIs[1].toBigInteger();
+			var m = data.toBigInteger();
+			return [rsa.encrypt(m,e,n)];
+		case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
+			var elgamal = new Elgamal();
+			var p = publicMPIs[0].toBigInteger();
+			var g = publicMPIs[1].toBigInteger();
+			var y = publicMPIs[2].toBigInteger();
+			var m = data.toBigInteger();
+			return elgamal.encrypt(m,g,p,y);
+		default:
+			return [];
+		}
+	})();
+
+	return result.map(function(bn) {
+		var mpi = new openpgp_type_mpi();
+		mpi.fromBigInteger(bn);
+		return mpi;
+	});
 }
 
 /**
@@ -57,32 +65,37 @@ function openpgp_crypto_asymetricEncrypt(algo, publicMPIs, data) {
  * @param {openpgp_type_mpi[]} secretMPIs Algorithm dependent multiprecision integers 
  * of the private key used
  * @param {openpgp_type_mpi} data Data to be encrypted as MPI
- * @return {BigInteger} returns a big integer containing the decrypted data; otherwise null
+ * @return {openpgp_type_mpi} returns a big integer containing the decrypted data; otherwise null
  */
 
 function openpgp_crypto_asymetricDecrypt(algo, publicMPIs, secretMPIs, dataMPIs) {
-	switch(algo) {
-	case 1: // RSA (Encrypt or Sign) [HAC]  
-	case 2: // RSA Encrypt-Only [HAC]
-	case 3: // RSA Sign-Only [HAC]
-		var rsa = new RSA();
-		var d = secretMPIs[0].toBigInteger();
-		var p = secretMPIs[1].toBigInteger();
-		var q = secretMPIs[2].toBigInteger();
-		var u = secretMPIs[3].toBigInteger();
-		var m = dataMPIs[0].toBigInteger();
-		return rsa.decrypt(m, d, p, q, u);
-	case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
-		var elgamal = new Elgamal();
-		var x = secretMPIs[0].toBigInteger();
-		var c1 = dataMPIs[0].toBigInteger();
-		var c2 = dataMPIs[1].toBigInteger();
-		var p = publicMPIs[0].toBigInteger();
-		return elgamal.decrypt(c1,c2,p,x);
-	default:
-		return null;
-	}
-	
+	var bn = (function() {
+		switch(algo) {
+		case 1: // RSA (Encrypt or Sign) [HAC]  
+		case 2: // RSA Encrypt-Only [HAC]
+		case 3: // RSA Sign-Only [HAC]
+			var rsa = new RSA();
+			var d = secretMPIs[0].toBigInteger();
+			var p = secretMPIs[1].toBigInteger();
+			var q = secretMPIs[2].toBigInteger();
+			var u = secretMPIs[3].toBigInteger();
+			var m = dataMPIs[0].toBigInteger();
+			return rsa.decrypt(m, d, p, q, u);
+		case 16: // Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
+			var elgamal = new Elgamal();
+			var x = secretMPIs[0].toBigInteger();
+			var c1 = dataMPIs[0].toBigInteger();
+			var c2 = dataMPIs[1].toBigInteger();
+			var p = publicMPIs[0].toBigInteger();
+			return elgamal.decrypt(c1,c2,p,x);
+		default:
+			return null;
+		}
+	})();
+
+	var result = new openpgp_type_mpi();
+	result.fromBigInteger(bn);
+	return result;
 }
 
 /**
diff --git a/src/packet/public_key_encrypted_session_key.js b/src/packet/public_key_encrypted_session_key.js
index e90b982c..b3e0ba70 100644
--- a/src/packet/public_key_encrypted_session_key.js
+++ b/src/packet/public_key_encrypted_session_key.js
@@ -60,9 +60,7 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		}
 
 		this.version = bytes[0].charCodeAt();
-
 		this.public_key_id.read_packet(bytes, 1);
-
 		this.public_key_algorithm = bytes[9].charCodeAt();
 
 		var i = 10;
@@ -73,16 +71,15 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		case openpgp.publickey.rsa_encrypt_sign:
 			this.encrypted = [];
 			this.encrypted[0] = new openpgp_type_mpi();
-			this.encrypted[0].read(bytes, i, bytes.length - i);
+			this.encrypted[0].read(bytes.substr(i));
 			break;
 
 		case openpgp.publickey.elgamal:
 			this.encrypted = [];
 			this.encrypted[0] = new openpgp_type_mpi();
-			this.encrypted[0].read(bytes, i, bytes.length - i);
-			i += this.encrypted[0].packetLength;
+			i += this.encrypted[0].read(bytes.substr(i));
 			this.encrypted[1] = new openpgp_type_mpi();
-			this.encrypted[1].read(bytes, i, bytes.length - i);
+			this.encrypted[1].read(bytes.substr(i));
 			break;
 
 		default:
@@ -118,7 +115,7 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		result += String.fromCharCode(this.public_key_algorithm);
 
 		for ( var i = 0; i < this.encrypted.length; i++) {
-			result += this.encrypted[i].toBin();
+			result += this.encrypted[i].write()
 		}
 
 		return result;
@@ -133,20 +130,14 @@ function openpgp_packet_public_key_encrypted_session_key() {
 		data += String.fromCharCode((checksum) & 0xFF);
 
 		var mpi = new openpgp_type_mpi();
+		mpi.fromBytes(openpgp_encoding_eme_pkcs1_encode(
+			data,
+			public_key_mpi[0].byteLength()));
 
-		var encrypted = openpgp_crypto_asymetricEncrypt(
+		this.encrypted = openpgp_crypto_asymetricEncrypt(
 			this.public_key_algorithm, 
 			public_key_mpi,
-			mpi.create(openpgp_encoding_eme_pkcs1_encode(data,
-					public_key_mpi[0].mpiByteLength)));
-
-		// TODO: fix this - make openpgp_crypto_ interfaces uniform
-		this.encrypted = encrypted.map(function(k) {
-				var mpi = new openpgp_type_mpi;
-				var b = k.toMPI();
-				mpi.read(b, 0, b.length);
-				return mpi;
-			});
+			mpi);
 	}
 
 	/**
@@ -164,16 +155,16 @@ function openpgp_packet_public_key_encrypted_session_key() {
 				this.public_key_algorithm,
 				public_key_mpi,
 				private_key_mpi,
-				this.encrypted).toMPI();
+				this.encrypted).toBytes();
 
-		var checksum = ((result.charCodeAt(result.length - 2) << 8) + result
-				.charCodeAt(result.length - 1));
+		var checksum = ((result.charCodeAt(result.length - 2) << 8) 
+			+ result.charCodeAt(result.length - 1));
 
 		var decoded = openpgp_encoding_eme_pkcs1_decode(
-			result.substring(2, result.length - 2), 
-			public_key_mpi[0].getByteLength());
+			result,
+			public_key_mpi[0].byteLength());
 
-		var key = decoded.substring(1);
+		var key = decoded.substring(1, decoded.length - 2);
 
 		if(checksum != util.calc_checksum(key)) {
 			util.print_error("Checksum mismatch");
diff --git a/src/type/openpgp.type.mpi.js b/src/type/mpi.js
similarity index 61%
rename from src/type/openpgp.type.mpi.js
rename to src/type/mpi.js
index 82f56690..2b019a2b 100644
--- a/src/type/openpgp.type.mpi.js
+++ b/src/type/mpi.js
@@ -31,10 +31,9 @@
  * actual integer.
  */
 function openpgp_type_mpi() {
-	this.MPI = null;
-	this.mpiBitLength = null;
-	this.mpiByteLength = null;
+	/** An implementation dependent integer */
 	this.data = null;
+
 	/**
 	 * Parsing function for a mpi (RFC 4880 3.2).
 	 * @param {String} input Payload of mpi data
@@ -44,10 +43,8 @@ function openpgp_type_mpi() {
 	 * input at position
 	 * @return {openpgp_type_mpi} Object representation
 	 */
-	function read(input, position, len) {
-		var mypos = position;
-		
-		this.mpiBitLength = (input[mypos++].charCodeAt() << 8) | input[mypos++].charCodeAt();
+	this.read = function(bytes) {
+		var bits = (bytes[0].charCodeAt() << 8) | bytes[1].charCodeAt();
 		
 		// Additional rules:
 		//
@@ -59,77 +56,50 @@ function openpgp_type_mpi() {
 
 		// TODO: Verification of this size method! This size calculation as
 		// 		 specified above is not applicable in JavaScript
-		this.mpiByteLength = (this.mpiBitLength - (this.mpiBitLength % 8)) / 8;
-		if (this.mpiBitLength % 8 != 0)
-			this.mpiByteLength++;
+		var bytelen = Math.ceil(bits / 8);
 		
-		this.MPI = input.substring(mypos,mypos+this.mpiByteLength);
-		this.data = input.substring(position, position+2+this.mpiByteLength);
-		this.packetLength = this.mpiByteLength +2;
-		return this;
-	}
-	
-	/**
-	 * Generates debug output (pretty print)
-	 * @return {String} String which gives some information about the mpi
-	 */
-	function toString() {
-		var r = "    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x";
-		r+=util.hexstrdump(this.MPI);
-		return r+'\n';
-	}
-	
-	/**
-	 * Converts the mpi to an BigInteger object
-	 * @return {BigInteger}
-	 */
-	function getBigInteger() {
-		return new BigInteger(util.hexstrdump(this.MPI),16); 
+		var raw = bytes.substr(2, bytelen);
+		this.fromBytes(raw);
+
+		return 2 + bytelen;
 	}
 
-	
-	function getBits(num) {
-		for (var i = 0; i < 9; i++)
-		if (num >> i == 0)
-		return i;
+	this.fromBytes = function(bytes) {
+		this.data = new BigInteger(util.hexstrdump(bytes), 16); 
 	}
-	
-	/**
-	 * Gets the length of the mpi in bytes
-	 * @return {Integer} Mpi byte length
-	 */
-	function getByteLength() {
-		return this.mpiByteLength;
+
+	this.toBytes = function() {
+		return this.write().substr(2);
 	}
-	
-	/**
-	 * Creates an mpi from the specified string
-	 * @param {String} data Data to read the mpi from
-	 * @return {openpgp_type_mpi} 
-	 */
-	function create(data) {
-		this.MPI = data;
-		this.mpiBitLength = (data.length -1) *8 + getBits(data.charCodeAt(0));
-		this.mpiByteLength = data.length;
-		return this;
+
+	this.byteLength = function() {
+		return this.toBytes().length;
 	}
-	
+
 	/**
 	 * Converts the mpi object to a string as specified in RFC4880 3.2
 	 * @return {String} mpi Byte representation
 	 */
-	function toBin() {
-		var result = String.fromCharCode((this.mpiBitLength >> 8) & 0xFF);
-		result += String.fromCharCode(this.mpiBitLength & 0xFF);
-		result += this.MPI;
-		return result;
+	this.write = function() {
+		return this.data.toMPI();
+	}
+
+	this.toBigInteger = function() {
+		return this.data.clone();
+	}
+
+	this.fromBigInteger = function(bn) {
+		this.data = bn.clone();
+	}
+
+	/**
+	 * Generates debug output (pretty print)
+	 * @return {String} String which gives some information about the mpi
+	 */
+	this.toString = function() {
+		var r = "    MPI("+this.mpiBitLength+"b/"+this.mpiByteLength+"B) : 0x";
+		r+=util.hexstrdump(this.MPI);
+		return r+'\n';
 	}
-	
-	this.read = read;
-	this.toBigInteger = getBigInteger;
-	this.toString = toString;
-	this.create = create;
-	this.toBin = toBin;
-	this.getByteLength = getByteLength;
 }
 
diff --git a/src/type/openpgp.type.keyid.js b/src/type/openpgp.type.keyid.js
index d8c1ac7a..aa7a9833 100644
--- a/src/type/openpgp.type.keyid.js
+++ b/src/type/openpgp.type.keyid.js
@@ -24,6 +24,10 @@
    formed.
  */
 function openpgp_type_keyid() {
+	var bytes = '';
+
+	for(var i = 0; i < 8; i++)
+		bytes += String.fromCharCode(0);
 	/**
 	 * Parsing method for a key id
 	 * @param {String} input Input to read the key id from 
diff --git a/test/general/packet.js b/test/general/packet.js
index 682d1cbf..eb72c1f0 100644
--- a/test/general/packet.js
+++ b/test/general/packet.js
@@ -38,6 +38,8 @@ unittests.register("Packet testing", function() {
 		enc.packets.push(literal);
 		enc.encrypt(algo, key);
 		msg.push(enc);
+		
+
 
 		var msg2 = new openpgp_packetlist();
 		msg2.read(msg.write());
@@ -82,16 +84,22 @@ unittests.register("Packet testing", function() {
 			key = rsa.generate(512, "10001")
 
 
-		var key = [[key.d.toMPI(), key.p.toMPI(), key.q.toMPI(), key.u.toMPI()],
-			[key.n.toMPI(), key.ee.toMPI()]];
+		var key = [
+			[key.d, key.p, key.q, key.u],
+			[key.n, key.ee]];
 
 		key = key.map(function(k) {
-			return k.map(function(v) {
+			return k.map(function(bn) {
 				var mpi = new openpgp_type_mpi();
-				mpi.read(v, 0, v.length);
+				mpi.fromBigInteger(bn);
 				return mpi;
 				});
 		});
+
+		var mpi = new openpgp_type_mpi();
+		mpi.fromBigInteger(key[0][1].data);
+		mpi.read(mpi.write());
+
 		var enc = new openpgp_packet_public_key_encrypted_session_key(),
 			msg = new openpgp_packetlist(),
 			msg2 = new openpgp_packetlist();
@@ -113,6 +121,8 @@ unittests.register("Packet testing", function() {
 			msg2[0].symmetric_algorithm == enc.symmetric_algorithm);
 	}];
 
+	tests.reverse();
+
 	var results = [];
 
 	for(var i in tests) {
@@ -121,4 +131,4 @@ unittests.register("Packet testing", function() {
 	
 	
 	return results;
-})
+});