'Copyright (c) 2000 Oren Novotny (osn@po.cwru.edu)
'Permission is granted to use this code for anything.
'Derived from the RSA Data Security, Inc. MD4 Message-Digest Algorithm.
'http://www.rsasecurity.com">RSA Data Security, Inc.</a> requires
'attribution for any work that is derived from the MD4 Message-Digest
'Algorithm; for details see <a href="http://www.roxen.com/rfc/rfc1320.html">
'RFC 1320</a>.
'This code is ported from Norbert Hranitzky's
'(norbert.hranitzky@mchp.siemens.de)
'Java version.
'Copyright (c) 2008 Luca Mauri (http://www.lucamauri.com)
'The orginal version found at http://www.derkeiler.com/Newsgroups/microsoft.public.dotnet.security/2004-08/0004.html
'was not working. I corrected and modified it so the current version is
'now calculating proper MD4 checksum.
Imports System
Imports System.Text
Namespace MD4Hash
'Implements the MD4 message digest algorithm in VB.Net
' Ronald L. Rivest,
' http://www.roxen.com/rfc/rfc1320.html
' The MD4 Message-Digest Algorithm
' IETF RFC-1320 (informational).
Public Class MD4
#Region "MD4 specific object variables"
' The size in bytes of the input block to the transformation algorithm
Private Const BLOCK_LENGTH As Integer = 64 ' = 512 / 8
' 4 32-bit words (interim result)
Private context(4 - 1) As UInt32
' Number of bytes procesed so far mod. 2 power of 64.
Private count As Long
' 512-bit input buffer = 16 x 32-bit words holds until it reaches 512 bits
Private buffer(BLOCK_LENGTH - 1) As Byte
' 512-bit work buffer = 16 x 32-bit words
Private X(16 - 1) As UInt32
#End Region
#Region "Constructors"
Public Sub New()
engineReset()
End Sub
' This constructor is here to implement the clonability of this class
Private Sub New(ByVal md As MD4)
context = CType(md.context.Clone(), UInt32())
buffer = CType(md.buffer.Clone(), Byte())
count = md.count
End Sub
#End Region
#Region "Clonable method implementation"
Public Function Clone() As Object
Return New MD4(Me)
End Function
#End Region
#Region "JCE methods"
' Resets this object disregarding any temporary data present at the
' time of the invocation of this call.
Private Sub engineReset()
' initial values of MD4 i.e. A, B, C, D
' as per rfc-1320; they are low-order byte first
context(0) = 1732584193
context(1) = 4023233417
context(2) = 2562383102
context(3) = 271733878
count = 0
Dim i As Integer = 0
Do While i < BLOCK_LENGTH
buffer(i) = 0
i += 1
Loop
End Sub
' Continues an MD4 message digest using the input byte
' byte to input
Private Sub engineUpdate(ByVal b As Byte)
' compute number of bytes still unhashed; ie. present in buffer
Dim i As Integer = CType(count Mod BLOCK_LENGTH, Integer)
count += 1 ' update number of bytes
buffer(i) = b
If i = (BLOCK_LENGTH - 1) Then
transform(buffer, 0)
End If
End Sub
' MD4 block update operation
' Continues an MD4 message digest operation by filling the buffer,
' transform(ing) data in 512-bit message block(s), updating the variables
' context and count, and leaving (buffering) the remaining bytes in buffer
' for the next update or finish.
' input = input block
' offset = start of meaningful bytes in input
' len = count of bytes in input blcok to consider
Private Sub engineUpdate(ByVal input() As Byte, ByVal offset As Integer, ByVal len As Integer)
' make sure we don't exceed input's allocated size/length
If (offset < 0 Or len < 0 Or CType(offset, Integer) + len > input.Length) Then
Throw New ArgumentOutOfRangeException()
End If
' compute number of bytes still unhashed; ie. present in buffer
Dim bufferNdx As Integer = CType(count Mod BLOCK_LENGTH, Integer)
count += len ' update number of bytes
Dim partLen As Integer = BLOCK_LENGTH - bufferNdx
Dim i As Integer = 0
If len >= partLen Then
Array.Copy(input, offset + i, buffer, bufferNdx, partLen)
transform(buffer, 0)
i = partLen
Do While (i + BLOCK_LENGTH - 1) < len
Console.WriteLine("Sono qui")
transform(input, offset + i)
i += BLOCK_LENGTH
Loop
bufferNdx = 0
End If
' buffer remaining input
If i < len Then
Array.Copy(input, offset + i, buffer, bufferNdx, len - i)
End If
End Sub
' Completes the hash computation by performing final operations such
' as padding. At the return of this engineDigest, the MD engine is
' reset.
' returns the array of bytes for the resulting hash value.
Private Function engineDigest() As Byte()
' pad output to 56 mod 64; as RFC1320 puts it: congruent to 448 mod 512
Dim bufferNdx As Integer = CType(count Mod BLOCK_LENGTH, Integer)
Dim padLen As Integer
If bufferNdx < 56 Then
padLen = 56 - bufferNdx
Else
padLen = 120 - bufferNdx
End If
' padding is always binary 1 followed by binary 0's
Dim tail(padLen + 8 - 1) As Byte
tail(0) = CType(128, Byte)
' append length before final transform
' save number of bits, casting the long to an array of 8 bytes
' save low-order byte first.
Dim TempArray As Byte()
TempArray = BitConverter.GetBytes(count * 8)
TempArray.CopyTo(tail, padLen)
engineUpdate(tail, 0, tail.Length)
Dim result(16 - 1) As Byte
For i As Integer = 0 To 3
Dim TempStore(4 - 1) As Byte
TempStore = BitConverter.GetBytes(context(i))
TempStore.CopyTo(result, i * 4)
Next
' reset the engine
engineReset()
Return result
End Function
' Returns a byte hash from a string
' s = string to hash
' returns byte-array that contains the hash
Public Function GetByteHashFromString(ByVal s As String) As Byte()
Dim b() As Byte = Encoding.UTF8.GetBytes(s)
Dim _md4 As MD4 = New MD4()
_md4.engineUpdate(b, 0, b.Length)
Return _md4.engineDigest()
End Function
' Returns a binary hash from an input byte array
' b = byte-array to hash
' returns binary hash of input
Public Function GetByteHashFromBytes(ByVal b() As Byte) As Byte()
Dim _md4 As MD4 = New MD4()
_md4.engineUpdate(b, 0, b.Length)
Return _md4.engineDigest()
End Function
' Returns a string that contains the hexadecimal hash
' b = byte-array to input
' returns String that contains the hex of the hash
Public Function GetHexHashFromBytes(ByVal b() As Byte) As String
Dim e() As Byte = GetByteHashFromBytes(b)
Return bytesToHex(e, e.Length)
End Function
' Returns a byte hash from the input byte
' b = byte to hash
' returns binary hash of the input byte
Public Function GetByteHashFromByte(ByVal b As Byte) As Byte()
Dim _md4 As MD4 = New MD4()
_md4.engineUpdate(b)
Return _md4.engineDigest()
End Function
' Returns a string that contains the hexadecimal hash
' b = byte to hash
' returns String that contains the hex of the hash
Public Function GetHexHashFromByte(ByVal b As Byte) As String
Dim e() As Byte = GetByteHashFromByte(b)
Return bytesToHex(e, e.Length)
End Function
' Returns a string that contains the hexadecimal hash
' s = string to hash
' returns String that contains the hex of the hash
Public Function GetHexHashFromString(ByVal s As String) As String
Dim b() As Byte = GetByteHashFromString(s)
Return bytesToHex(b, b.Length)
End Function
Private Shared Function bytesToHex(ByVal a() As Byte, ByVal len As Integer) As String
Dim temp As String = BitConverter.ToString(a)
Dim i As Integer
' We need to remove the dashes that come from the BitConverter
Dim sb As StringBuilder = New StringBuilder(CType((len - 2) / 2, Integer)) ' This should be the final size
For i = 0 To temp.Length - 1 Step 1
If temp(i) <> "-" Then
sb.Append(temp(i))
End If
Next
Return sb.ToString()
End Function
#End Region
#Region "own methods"
' MD4 basic transformation
' Transforms context based on 512 bits from input block starting
' from the offset'th byte.
' block = input sub-array
' offset = starting position of sub-array
Private Sub transform(ByRef block() As Byte, ByVal offset As Integer)
' decodes 64 bytes from input block into an array of 16 32-bit
' entities. Use A as a temp var.
Dim i As Integer
For i = 0 To 15 Step 1
If offset >= block.Length Then
Exit For
End If
X(i) = (CType(block(offset + 0), UInt32) And 255) Or _
(CType(block(offset + 1), UInt32) And 255) << 8 Or _
(CType(block(offset + 2), UInt32) And 255) << 16 Or _
(CType(block(offset + 3), UInt32) And 255) << 24
offset += 4
Next
Dim A As UInt32 = context(0)
Dim B As UInt32 = context(1)
Dim C As UInt32 = context(2)
Dim D As UInt32 = context(3)
A = FF(A, B, C, D, X(0), 3)
D = FF(D, A, B, C, X(1), 7)
C = FF(C, D, A, B, X(2), 11)
B = FF(B, C, D, A, X(3), 19)
A = FF(A, B, C, D, X(4), 3)
D = FF(D, A, B, C, X(5), 7)
C = FF(C, D, A, B, X(6), 11)
B = FF(B, C, D, A, X(7), 19)
A = FF(A, B, C, D, X(8), 3)
D = FF(D, A, B, C, X(9), 7)
C = FF(C, D, A, B, X(10), 11)
B = FF(B, C, D, A, X(11), 19)
A = FF(A, B, C, D, X(12), 3)
D = FF(D, A, B, C, X(13), 7)
C = FF(C, D, A, B, X(14), 11)
B = FF(B, C, D, A, X(15), 19)
A = GG(A, B, C, D, X(0), 3)
D = GG(D, A, B, C, X(4), 5)
C = GG(C, D, A, B, X(8), 9)
B = GG(B, C, D, A, X(12), 13)
A = GG(A, B, C, D, X(1), 3)
D = GG(D, A, B, C, X(5), 5)
C = GG(C, D, A, B, X(9), 9)
B = GG(B, C, D, A, X(13), 13)
A = GG(A, B, C, D, X(2), 3)
D = GG(D, A, B, C, X(6), 5)
C = GG(C, D, A, B, X(10), 9)
B = GG(B, C, D, A, X(14), 13)
A = GG(A, B, C, D, X(3), 3)
D = GG(D, A, B, C, X(7), 5)
C = GG(C, D, A, B, X(11), 9)
B = GG(B, C, D, A, X(15), 13)
A = HH(A, B, C, D, X(0), 3)
D = HH(D, A, B, C, X(8), 9)
C = HH(C, D, A, B, X(4), 11)
B = HH(B, C, D, A, X(12), 15)
A = HH(A, B, C, D, X(2), 3)
D = HH(D, A, B, C, X(10), 9)
C = HH(C, D, A, B, X(6), 11)
B = HH(B, C, D, A, X(14), 15)
A = HH(A, B, C, D, X(1), 3)
D = HH(D, A, B, C, X(9), 9)
C = HH(C, D, A, B, X(5), 11)
B = HH(B, C, D, A, X(13), 15)
A = HH(A, B, C, D, X(3), 3)
D = HH(D, A, B, C, X(11), 9)
C = HH(C, D, A, B, X(7), 11)
B = HH(B, C, D, A, X(15), 15)
context(0) = TruncateHex(context(0) + Convert.ToInt64(A))
context(1) = TruncateHex(context(1) + Convert.ToInt64(B))
context(2) = TruncateHex(context(2) + Convert.ToInt64(C))
context(3) = TruncateHex(context(3) + Convert.ToInt64(D))
End Sub
#End Region
#Region "The basic MD4 atomic functions."
Private Function FF(ByVal a As UInt32, ByVal b As UInt32, ByVal c As UInt32, ByVal d As UInt32, ByVal x As UInt32, ByVal s As Integer) As UInt32
Dim t As UInt32
Try
t = TruncateHex(TruncateHex(Convert.ToInt64(a) + ((b And c) Or ((Not b) And d))) + Convert.ToInt64(x))
Return (t << s) Or (t >> (32 - s))
Catch ex As Exception
Return (t << s) Or (t >> (32 - s))
End Try
End Function
Private Function GG(ByVal a As UInt32, ByVal b As UInt32, ByVal c As UInt32, ByVal d As UInt32, ByVal x As UInt32, ByVal s As Integer) As UInt32
Dim t As UInt32
Try
t = TruncateHex(TruncateHex(Convert.ToInt64(a) + ((b And (c Or d)) Or (c And d))) + Convert.ToInt64(x) + 1518500249) '&H5A827999
Return t << s Or t >> (32 - s)
Catch
Return t << s Or t >> (32 - s)
End Try
End Function
Private Function HH(ByVal a As UInt32, ByVal b As UInt32, ByVal c As UInt32, ByVal d As UInt32, ByVal x As UInt32, ByVal s As Integer) As UInt32
Dim t As UInt32
Try
t = TruncateHex(TruncateHex(Convert.ToInt64(a) + (b Xor c Xor d)) + Convert.ToInt64(x) + 1859775393) '&H6ED9EBA1
Return t << s Or t >> (32 - s)
Catch
Return t << s Or t >> (32 - s)
End Try
End Function
#End Region
#Region "Support functions"
Private Function TruncateHex(ByVal Number64 As UInt64) As UInt32
Dim HexString As String
Dim HexStringLimited As String
HexString = Number64.ToString("x")
If HexString.Length < 8 Then
HexStringLimited = HexString.PadLeft(8, "0")
Else
HexStringLimited = HexString.Substring(HexString.Length - 8)
End If
Return UInt32.Parse(HexStringLimited, Globalization.NumberStyles.HexNumber)
End Function
#End Region
End Class
End Namespace
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