I google it from web, find many samples to generate a new x509Certificate2 from a file in .net, but there is no one sample to show how to generate a completely new x509Certificate2 from the beginning in .net.
Is there any one that can tell me how to do it in .net?
Thank you very much.
Here is an example of the complete x509Certificate2 to both create and read.
Imports System Imports System.Security.Cryptography Imports System.Security.Cryptography.X509Certificates Imports System.IO Imports System.Text
' To run this sample use the Certificate Creation Tool (Makecert.exe) to generate a test X.509 certificate and ' place it in the local user store. ' To generate an exchange key and make the key exportable run the following command from a Visual Studio command prompt: 'makecert -r -pe -n "CN=CERT_SIGN_TEST_CERT" -b 01/01/2010 -e 01/01/2012 -sky exchange -ss my
Class Program
' Path variables for source, encryption, and
' decryption folders. Must end with a backslash.
Private Shared encrFolder As String = "C:\Encrypt\"
Private Shared decrFolder As String = "C:\Decrypt\"
Private Shared originalFile As String = "TestData.txt"
Private Shared encryptedFile As String = "TestData.enc"
Shared Sub Main(ByVal args() As String)
' Create an input file with test data.
Dim sw As StreamWriter = File.CreateText(originalFile)
sw.WriteLine("Test data to be encrypted")
sw.Close()
' Get the certifcate to use to encrypt the key.
Dim cert As X509Certificate2 = GetCertificateFromStore("CN=CERT_SIGN_TEST_CERT")
If cert Is Nothing Then
Console.WriteLine("Certificatge 'CN=CERT_SIGN_TEST_CERT' not found.")
Console.ReadLine()
End If
' Encrypt the file using the public key from the certificate.
EncryptFile(originalFile, CType(cert.PublicKey.Key, RSACryptoServiceProvider))
' Decrypt the file using the private key from the certificate.
DecryptFile(encryptedFile, CType(cert.PrivateKey, RSACryptoServiceProvider))
'Display the original data and the decrypted data.
Console.WriteLine("Original: {0}", File.ReadAllText(originalFile))
Console.WriteLine("Round Trip: {0}", File.ReadAllText(decrFolder + originalFile))
Console.WriteLine("Press the Enter key to exit.")
Console.ReadLine()
End Sub 'Main
Private Shared Function GetCertificateFromStore(ByVal certName As String) As X509Certificate2
' Get the certificate store for the current user.
Dim store As New X509Store(StoreLocation.CurrentUser)
Try
store.Open(OpenFlags.ReadOnly)
' Place all certificates in an X509Certificate2Collection object.
Dim certCollection As X509Certificate2Collection = store.Certificates
' If using a certificate with a trusted root you do not need to FindByTimeValid, instead use:
' currentCerts.Find(X509FindType.FindBySubjectDistinguishedName, certName, true);
Dim currentCerts As X509Certificate2Collection = certCollection.Find(X509FindType.FindByTimeValid, DateTime.Now, False)
Dim signingCert As X509Certificate2Collection = currentCerts.Find(X509FindType.FindBySubjectDistinguishedName, certName, False)
If signingCert.Count = 0 Then
Return Nothing
End If ' Return the first certificate in the collection, has the right name and is current.
Return signingCert(0)
Finally
store.Close()
End Try
End Function 'GetCertificateFromStore
' Encrypt a file using a public key.
Private Shared Sub EncryptFile(ByVal inFile As String, ByVal rsaPublicKey As RSACryptoServiceProvider)
Dim aesManaged As New AesManaged()
Try
' Create instance of AesManaged for
' symetric encryption of the data.
aesManaged.KeySize = 256
aesManaged.BlockSize = 128
aesManaged.Mode = CipherMode.CBC
Dim transform As ICryptoTransform = aesManaged.CreateEncryptor()
Try
Dim keyFormatter As New RSAPKCS1KeyExchangeFormatter(rsaPublicKey)
Dim keyEncrypted As Byte() = keyFormatter.CreateKeyExchange(aesManaged.Key, aesManaged.GetType())
' Create byte arrays to contain
' the length values of the key and IV.
Dim LenK(3) As Byte
Dim LenIV(3) As Byte
Dim lKey As Integer = keyEncrypted.Length
LenK = BitConverter.GetBytes(lKey)
Dim lIV As Integer = aesManaged.IV.Length
LenIV = BitConverter.GetBytes(lIV)
' Write the following to the FileStream
' for the encrypted file (outFs):
' - length of the key
' - length of the IV
' - ecrypted key
' - the IV
' - the encrypted cipher content
Dim startFileName As Integer = inFile.LastIndexOf("\") + 1
' Change the file's extension to ".enc"
Dim outFile As String = encrFolder + inFile.Substring(startFileName, inFile.LastIndexOf(".") - startFileName) + ".enc"
Directory.CreateDirectory(encrFolder)
Dim outFs As New FileStream(outFile, FileMode.Create)
Try
outFs.Write(LenK, 0, 4)
outFs.Write(LenIV, 0, 4)
outFs.Write(keyEncrypted, 0, lKey)
outFs.Write(aesManaged.IV, 0, lIV)
' Now write the cipher text using
' a CryptoStream for encrypting.
Dim outStreamEncrypted As New CryptoStream(outFs, transform, CryptoStreamMode.Write)
Try
' By encrypting a chunk at
' a time, you can save memory
' and accommodate large files.
Dim count As Integer = 0
Dim offset As Integer = 0
' blockSizeBytes can be any arbitrary size.
Dim blockSizeBytes As Integer = aesManaged.BlockSize / 8
Dim data(blockSizeBytes) As Byte
Dim bytesRead As Integer = 0
Dim inFs As New FileStream(inFile, FileMode.Open)
Try
Do
count = inFs.Read(data, 0, blockSizeBytes)
offset += count
outStreamEncrypted.Write(data, 0, count)
bytesRead += blockSizeBytes
Loop While count > 0
inFs.Close()
Finally
inFs.Dispose()
End Try
outStreamEncrypted.FlushFinalBlock()
outStreamEncrypted.Close()
Finally
outStreamEncrypted.Dispose()
End Try
outFs.Close()
Finally
outFs.Dispose()
End Try
Finally
transform.Dispose()
End Try
Finally
aesManaged.Dispose()
End Try
End Sub 'EncryptFile
' Decrypt a file using a private key.
Private Shared Sub DecryptFile(ByVal inFile As String, ByVal rsaPrivateKey As RSACryptoServiceProvider)
' Create instance of AesManaged for
' symetric decryption of the data.
Dim aesManaged As New AesManaged()
Try
aesManaged.KeySize = 256
aesManaged.BlockSize = 128
aesManaged.Mode = CipherMode.CBC
' Create byte arrays to get the length of
' the encrypted key and IV.
' These values were stored as 4 bytes each
' at the beginning of the encrypted package.
Dim LenK() As Byte = New Byte(4 - 1) {}
Dim LenIV() As Byte = New Byte(4 - 1) {}
' Consruct the file name for the decrypted file.
Dim outFile As String = decrFolder + inFile.Substring(0, inFile.LastIndexOf(".")) + ".txt"
' Use FileStream objects to read the encrypted
' file (inFs) and save the decrypted file (outFs).
Dim inFs As New FileStream(encrFolder + inFile, FileMode.Open)
Try
inFs.Seek(0, SeekOrigin.Begin)
inFs.Seek(0, SeekOrigin.Begin)
inFs.Read(LenK, 0, 3)
inFs.Seek(4, SeekOrigin.Begin)
inFs.Read(LenIV, 0, 3)
' Convert the lengths to integer values.
Dim lengthK As Integer = BitConverter.ToInt32(LenK, 0)
Dim lengthIV As Integer = BitConverter.ToInt32(LenIV, 0)
' Determine the start postition of
' the ciphter text (startC)
' and its length(lenC).
Dim startC As Integer = lengthK + lengthIV + 8
Dim lenC As Integer = (CType(inFs.Length, Integer) - startC)
' Create the byte arrays for
' the encrypted Rijndael key,
' the IV, and the cipher text.
Dim KeyEncrypted() As Byte = New Byte(lengthK - 1) {}
Dim IV() As Byte = New Byte(lengthIV - 1) {}
' Extract the key and IV
' starting from index 8
' after the length values.
inFs.Seek(8, SeekOrigin.Begin)
inFs.Read(KeyEncrypted, 0, lengthK)
inFs.Seek(8 + lengthK, SeekOrigin.Begin)
inFs.Read(IV, 0, lengthIV)
Directory.CreateDirectory(decrFolder)
' Use RSACryptoServiceProvider
' to decrypt the Rijndael key.
Dim KeyDecrypted As Byte() = rsaPrivateKey.Decrypt(KeyEncrypted, False)
' Decrypt the key.
Dim transform As ICryptoTransform = aesManaged.CreateDecryptor(KeyDecrypted, IV)
' Decrypt the cipher text from
' from the FileSteam of the encrypted
' file (inFs) into the FileStream
' for the decrypted file (outFs).
Dim outFs As New FileStream(outFile, FileMode.Create)
Try
' Decrypt the cipher text from
' from the FileSteam of the encrypted
' file (inFs) into the FileStream
' for the decrypted file (outFs).
Dim count As Integer = 0
Dim offset As Integer = 0
Dim blockSizeBytes As Integer = aesManaged.BlockSize / 8
Dim data(blockSizeBytes) As Byte
' By decrypting a chunk a time,
' you can save memory and
' accommodate large files.
' Start at the beginning
' of the cipher text.
inFs.Seek(startC, SeekOrigin.Begin)
Dim outStreamDecrypted As New CryptoStream(outFs, transform, CryptoStreamMode.Write)
Try
Do
count = inFs.Read(data, 0, blockSizeBytes)
offset += count
outStreamDecrypted.Write(data, 0, count)
Loop While count > 0
outStreamDecrypted.FlushFinalBlock()
outStreamDecrypted.Close()
Finally
outStreamDecrypted.Dispose()
End Try
outFs.Close()
Finally
outFs.Dispose()
End Try
inFs.Close()
Finally
inFs.Dispose()
End Try
Finally
aesManaged.Dispose()
End Try
End Sub 'DecryptFile
End Class 'Program