| public C_DecryptUpdate ( uint session, byte encryptedPart, uint encryptedPartLen, byte part, uint &partLen ) : CKR | ||
| session | uint | The session's handle |
| encryptedPart | byte | Encrypted data part |
| encryptedPartLen | uint | Length of the encrypted data part |
| part | byte | /// If set to null then the length of decrypted data part is returned in "partLen" parameter, without actually returning decrypted data part. /// If not set to null then "partLen" parameter must contain the lenght of part array and decrypted data part is returned in "part" parameter. /// |
| partLen | uint | Location that holds the length of the decrypted data part |
| return | CKR | |
public void _02_EncryptAndDecryptMultiPartTest()
{
if (Platform.UnmanagedLongSize != 4 || Platform.StructPackingSize != 0)
Assert.Inconclusive("Test cannot be executed on this platform");
CKR rv = CKR.CKR_OK;
using (Pkcs11 pkcs11 = new Pkcs11(Settings.Pkcs11LibraryPath))
{
rv = pkcs11.C_Initialize(Settings.InitArgs40);
if ((rv != CKR.CKR_OK) && (rv != CKR.CKR_CRYPTOKI_ALREADY_INITIALIZED))
Assert.Fail(rv.ToString());
// Find first slot with token present
uint slotId = Helpers.GetUsableSlot(pkcs11);
uint session = CK.CK_INVALID_HANDLE;
rv = pkcs11.C_OpenSession(slotId, (CKF.CKF_SERIAL_SESSION | CKF.CKF_RW_SESSION), IntPtr.Zero, IntPtr.Zero, ref session);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Login as normal user
rv = pkcs11.C_Login(session, CKU.CKU_USER, Settings.NormalUserPinArray, Convert.ToUInt32(Settings.NormalUserPinArray.Length));
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Generate symetric key
uint keyId = CK.CK_INVALID_HANDLE;
rv = Helpers.GenerateKey(pkcs11, session, ref keyId);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Generate random initialization vector
byte[] iv = new byte[8];
rv = pkcs11.C_GenerateRandom(session, iv, Convert.ToUInt32(iv.Length));
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Specify encryption mechanism with initialization vector as parameter.
// Note that CkmUtils.CreateMechanism() automaticaly copies iv into newly allocated unmanaged memory.
CK_MECHANISM mechanism = CkmUtils.CreateMechanism(CKM.CKM_DES3_CBC, iv);
byte[] sourceData = ConvertUtils.Utf8StringToBytes("Our new password");
byte[] encryptedData = null;
byte[] decryptedData = null;
// Multipart encryption functions C_EncryptUpdate and C_EncryptFinal can be used i.e. for encryption of streamed data
using (MemoryStream inputStream = new MemoryStream(sourceData), outputStream = new MemoryStream())
{
// Initialize encryption operation
rv = pkcs11.C_EncryptInit(session, ref mechanism, keyId);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Prepare buffer for source data part
// Note that in real world application we would rather use bigger buffer i.e. 4096 bytes long
byte[] part = new byte[8];
// Prepare buffer for encrypted data part
// Note that in real world application we would rather use bigger buffer i.e. 4096 bytes long
byte[] encryptedPart = new byte[8];
uint encryptedPartLen = Convert.ToUInt32(encryptedPart.Length);
// Read input stream with source data
int bytesRead = 0;
while ((bytesRead = inputStream.Read(part, 0, part.Length)) > 0)
{
// Encrypt each individual source data part
encryptedPartLen = Convert.ToUInt32(encryptedPart.Length);
rv = pkcs11.C_EncryptUpdate(session, part, Convert.ToUInt32(bytesRead), encryptedPart, ref encryptedPartLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Append encrypted data part to the output stream
outputStream.Write(encryptedPart, 0, Convert.ToInt32(encryptedPartLen));
}
// Get the length of last encrypted data part in first call
byte[] lastEncryptedPart = null;
uint lastEncryptedPartLen = 0;
rv = pkcs11.C_EncryptFinal(session, null, ref lastEncryptedPartLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Allocate array for the last encrypted data part
lastEncryptedPart = new byte[lastEncryptedPartLen];
// Get the last encrypted data part in second call
rv = pkcs11.C_EncryptFinal(session, lastEncryptedPart, ref lastEncryptedPartLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Append the last encrypted data part to the output stream
outputStream.Write(lastEncryptedPart, 0, Convert.ToInt32(lastEncryptedPartLen));
// Read whole output stream to the byte array so we can compare results more easily
encryptedData = outputStream.ToArray();
}
// Do something interesting with encrypted data
// Multipart decryption functions C_DecryptUpdate and C_DecryptFinal can be used i.e. for decryption of streamed data
using (MemoryStream inputStream = new MemoryStream(encryptedData), outputStream = new MemoryStream())
{
// Initialize decryption operation
rv = pkcs11.C_DecryptInit(session, ref mechanism, keyId);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Prepare buffer for encrypted data part
// Note that in real world application we would rather use bigger buffer i.e. 4096 bytes long
byte[] encryptedPart = new byte[8];
// Prepare buffer for decrypted data part
// Note that in real world application we would rather use bigger buffer i.e. 4096 bytes long
byte[] part = new byte[8];
uint partLen = Convert.ToUInt32(part.Length);
// Read input stream with encrypted data
int bytesRead = 0;
while ((bytesRead = inputStream.Read(encryptedPart, 0, encryptedPart.Length)) > 0)
{
// Decrypt each individual encrypted data part
partLen = Convert.ToUInt32(part.Length);
rv = pkcs11.C_DecryptUpdate(session, encryptedPart, Convert.ToUInt32(bytesRead), part, ref partLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Append decrypted data part to the output stream
outputStream.Write(part, 0, Convert.ToInt32(partLen));
}
// Get the length of last decrypted data part in first call
byte[] lastPart = null;
uint lastPartLen = 0;
rv = pkcs11.C_DecryptFinal(session, null, ref lastPartLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Allocate array for the last decrypted data part
lastPart = new byte[lastPartLen];
// Get the last decrypted data part in second call
rv = pkcs11.C_DecryptFinal(session, lastPart, ref lastPartLen);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
// Append the last decrypted data part to the output stream
outputStream.Write(lastPart, 0, Convert.ToInt32(lastPartLen));
// Read whole output stream to the byte array so we can compare results more easily
decryptedData = outputStream.ToArray();
}
// Do something interesting with decrypted data
Assert.IsTrue(Convert.ToBase64String(sourceData) == Convert.ToBase64String(decryptedData));
// In LowLevelAPI we have to free unmanaged memory taken by mechanism parameter (iv in this case)
UnmanagedMemory.Free(ref mechanism.Parameter);
mechanism.ParameterLen = 0;
rv = pkcs11.C_DestroyObject(session, keyId);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
rv = pkcs11.C_Logout(session);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
rv = pkcs11.C_CloseSession(session);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
rv = pkcs11.C_Finalize(IntPtr.Zero);
if (rv != CKR.CKR_OK)
Assert.Fail(rv.ToString());
}
}