Cita:
Iniciado por jcgalle 
Hola cres que pudieras compartir con nosotros el codigo: clsSeguridad.DecodeEncryptedPrivateKeyInfo
Imports System
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography
Imports System.Security.Cryptography.X509Certificates
Imports System.Runtime.InteropServices
Imports System.Security
Imports System.Diagnostics
Imports System.ComponentModel
Public Class clsSeguridad_2
Shared verbose As Boolean = False
Private Sub SAT()
Dim aa As String = ""
End Sub
Public Shared Function CodificarMD5(ByVal input As String) As String
Dim CadenaUTF8 As Byte()
Dim tmpHash As Byte()
'convierte en UTF8
CadenaUTF8 = Encoding.UTF8.GetBytes(input)
'crea el hash
tmpHash = New MD5CryptoServiceProvider().ComputeHash(CadenaUTF8)
Dim i As Integer
Dim sOutput As StringBuilder = New StringBuilder(tmpHash.Length)
For i = 0 To tmpHash.Length - 1 Step 1
sOutput.Append(tmpHash(i).ToString("x2"))
Next
Return sOutput.ToString()
End Function
Public Shared Function DecodeEncryptedPrivateKeyInfo(ByVal encpkcs8 As Byte(), ByVal lSecStr As SecureString) As RSACryptoServiceProvider
Dim OIDpkcs5PBES2 As Byte() = {&H6, &H9, &H2A, &H86, &H48, &H86, &HF7, &HD, &H1, &H5, &HD}
Dim OIDpkcs5PBKDF2 As Byte() = {&H6, &H9, &H2A, &H86, &H48, &H86, &HF7, &HD, &H1, &H5, &HC}
Dim OIDdesEDE3CBC As Byte() = {&H6, &H8, &H2A, &H86, &H48, &H86, &HF7, &HD, &H3, &H7}
Dim seqdes As Byte() = New Byte(10) {}
Dim seq As Byte() = New Byte(10) {}
Dim salt As Byte()
Dim IV As Byte()
Dim encryptedpkcs8 As Byte()
Dim pkcs8 As Byte()
Dim saltsize, ivsize, encblobsize As Integer
Dim iterations As Integer
' '' --------- Set up stream to read the asn.1 encoded SubjectPublicKeyInfo blob ------
Dim mem As MemoryStream = New MemoryStream(encpkcs8)
Dim lenstream As Integer = Int(mem.Length)
Dim binr As BinaryReader = New BinaryReader(mem) 'wrap Memory Stream with BinaryReader for easy reading
Dim bt As Byte = 0
Dim twobytes As UShort = 0
Try
twobytes = binr.ReadUInt16()
If (twobytes = &H8130) Then 'data read as little endian order (actual data order for Sequence is 30 81)
binr.ReadByte() 'advance 1 byte
ElseIf (twobytes = &H8230) Then
binr.ReadInt16() 'advance 2 bytes
Else
Return Nothing
End If
twobytes = binr.ReadUInt16() 'inner sequence
If (twobytes = &H8130) Then
binr.ReadByte()
ElseIf (twobytes = &H8230) Then
binr.ReadInt16()
End If
seq = binr.ReadBytes(11) 'read the Sequence OID
If (Not CompareBytearrays(seq, OIDpkcs5PBES2)) Then 'is it a OIDpkcs5PBES2 ?
Return Nothing
End If
twobytes = binr.ReadUInt16() 'inner sequence for pswd salt
If (twobytes = &H8130) Then
binr.ReadByte()
ElseIf (twobytes = &H8230) Then
binr.ReadInt16()
End If
twobytes = binr.ReadUInt16() 'inner sequence for pswd salt
If (twobytes = &H8130) Then
binr.ReadByte()
ElseIf (twobytes = &H8230) Then
binr.ReadInt16()
End If
seq = binr.ReadBytes(11) 'read the Sequence OID
If (Not CompareBytearrays(seq, OIDpkcs5PBES2)) Then 'is it a OIDpkcs5PBES2 ?
Return Nothing
End If
twobytes = binr.ReadUInt16() 'inner sequence for pswd salt
If (twobytes = &H8130) Then
binr.ReadByte()
ElseIf (twobytes = &H8230) Then
binr.ReadInt16()
End If
bt = binr.ReadByte()
If (bt <> &H4) Then
Return Nothing
End If
saltsize = binr.ReadByte()
salt = binr.ReadBytes(saltsize)
If (verbose) Then
'showBytes("Salt for pbkd", salt)
End If
bt = binr.ReadByte()
If (bt <> &H2) Then 'expect an integer for PBKF2 interation count
Return Nothing
End If
Dim itbytes As Integer = binr.ReadByte() 'PBKD2 iterations should fit in 2 bytes.
If (itbytes = 1) Then
iterations = 256 * binr.ReadByte() + binr.ReadByte()
Else
Return Nothing
End If
If (verbose) Then
Console.WriteLine("PBKD2 iterations {0}", iterations)
End If
twobytes = binr.ReadUInt16()
If (twobytes = &H8130) Then
binr.ReadByte()
ElseIf (twobytes = &H8230) Then
binr.ReadInt16()
End If
seqdes = binr.ReadBytes(10) 'read the Sequence OID
If (Not CompareBytearrays(seqdes, OIDdesEDE3CBC)) Then 'is it a OIDdes-EDE3-CBC ?
Return Nothing
End If
bt = binr.ReadByte()
If (bt <> &H4) Then 'expect octet string for IV
Return Nothing
End If
ivsize = binr.ReadByte() 'IV byte size should fit in one byte (24 expected for 3DES)
IV = binr.ReadBytes(ivsize)
If (verbose) Then
'showBytes("IV for des-EDE3-CBC", IV)
End If
bt = binr.ReadByte()
If (bt <> &H4) Then 'expect octet string for encrypted PKCS8 data
Return Nothing
End If
bt = binr.ReadByte()
'bt = binr.ReadByte();
If (bt = &H81) Then
encblobsize = binr.ReadByte() ' data size in next byte
ElseIf (bt = &H82) Then
encblobsize = 256 * binr.ReadByte() + binr.ReadByte()
Else
encblobsize = bt ' we already have the data size
End If
encryptedpkcs8 = binr.ReadBytes(encblobsize)
Dim secpswd As SecureString = lSecStr 'GetSecPswd(lSecStr.ToString());
pkcs8 = DecryptPBDK2(encryptedpkcs8, salt, IV, secpswd, iterations)
If (pkcs8 Is Nothing) Then ' probably a bad pswd entered.
Return Nothing
End If
' ----- With a decrypted pkcs #8 PrivateKeyInfo blob, decode it to an RSA ---
Dim rsa As RSACryptoServiceProvider = DecodePrivateKeyInfo(pkcs8)
Return rsa
Catch ex As Exception
Return Nothing
Finally
binr.Close()
End Try
End Function
Private Shared Function CompareBytearrays(ByVal a As Byte(), ByVal b As Byte()) As Boolean
If (a.Length <> b.Length) Then
Return False
End If
Dim i As Integer = 0
For Each c As Byte In a
If (c <> b(i)) Then
Return False
i += 1
End If
Next
Return True
End Function