private unsafe void OpenCryptor(
Interop.AppleCrypto.PAL_SymmetricAlgorithm algorithm,
CipherMode cipherMode,
byte[] key)
{
int ret;
int ccStatus;
byte[]? iv = IV;
fixed(byte *pbKey = key)
fixed(byte *pbIv = iv)
{
ret = Interop.AppleCrypto.CryptorCreate(
_encrypting
? Interop.AppleCrypto.PAL_SymmetricOperation.Encrypt
: Interop.AppleCrypto.PAL_SymmetricOperation.Decrypt,
algorithm,
GetPalChainMode(cipherMode),
Interop.AppleCrypto.PAL_PaddingMode.None,
pbKey,
key.Length,
pbIv,
Interop.AppleCrypto.PAL_SymmetricOptions.None,
out _cryptor,
out ccStatus);
}
ProcessInteropError(ret, ccStatus);
}
private Interop.AppleCrypto.PAL_ChainingMode GetPalChainMode(Interop.AppleCrypto.PAL_SymmetricAlgorithm algorithm, CipherMode cipherMode, int feedbackSizeInBytes)
{
switch (cipherMode)
{
case CipherMode.CBC:
return(Interop.AppleCrypto.PAL_ChainingMode.CBC);
case CipherMode.ECB:
return(Interop.AppleCrypto.PAL_ChainingMode.ECB);
case CipherMode.CFB:
if (feedbackSizeInBytes == 1)
{
return(Interop.AppleCrypto.PAL_ChainingMode.CFB8);
}
Debug.Assert(
(algorithm == Interop.AppleCrypto.PAL_SymmetricAlgorithm.AES && feedbackSizeInBytes == 16) ||
(algorithm == Interop.AppleCrypto.PAL_SymmetricAlgorithm.TripleDES && feedbackSizeInBytes == 8));
return(Interop.AppleCrypto.PAL_ChainingMode.CFB);
default:
throw new PlatformNotSupportedException(SR.Format(SR.Cryptography_CipherModeNotSupported, cipherMode));
}
}
private PAL_ChainingMode GetPalChainMode(PAL_SymmetricAlgorithm algorithm, CipherMode cipherMode, int feedbackSizeInBytes)
{
return(cipherMode switch
{
CipherMode.CBC => PAL_ChainingMode.CBC,
CipherMode.ECB => PAL_ChainingMode.ECB,
CipherMode.CFB when feedbackSizeInBytes == 1 => PAL_ChainingMode.CFB8,
CipherMode.CFB => PAL_ChainingMode.CFB,
_ => throw new PlatformNotSupportedException(SR.Format(SR.Cryptography_CipherModeNotSupported, cipherMode)),
});
public AppleCCCryptor(
Interop.AppleCrypto.PAL_SymmetricAlgorithm algorithm,
CipherMode cipherMode,
int blockSizeInBytes,
byte[] key,
byte[]?iv,
bool encrypting)
: base(cipherMode.GetCipherIv(iv), blockSizeInBytes)
{
_encrypting = encrypting;
OpenCryptor(algorithm, cipherMode, key);
}
public AppleCCCryptor(
Interop.AppleCrypto.PAL_SymmetricAlgorithm algorithm,
CipherMode cipherMode,
int blockSizeInBytes,
byte[] key,
byte[]?iv,
bool encrypting,
int feedbackSizeInBytes,
int paddingSizeInBytes)
: base(cipherMode.GetCipherIv(iv), blockSizeInBytes, paddingSizeInBytes)
{
_encrypting = encrypting;
// CFB is streaming cipher, calling CCCryptorReset is not implemented (and is effectively noop)
_supportsReset = cipherMode != CipherMode.CFB;
_algorithm = algorithm;
_cipherMode = cipherMode;
_key = key;
_feedbackSizeInBytes = feedbackSizeInBytes;
OpenCryptor();
}
public unsafe AppleCCCryptorLite(
PAL_SymmetricAlgorithm algorithm,
CipherMode cipherMode,
int blockSizeInBytes,
ReadOnlySpan <byte> key,
ReadOnlySpan <byte> iv,
bool encrypting,
int feedbackSizeInBytes,
int paddingSizeInBytes)
{
int ret;
int ccStatus;
fixed(byte *pbKey = key)
fixed(byte *pbIv = iv)
{
ret = Interop.AppleCrypto.CryptorCreate(
encrypting
? Interop.AppleCrypto.PAL_SymmetricOperation.Encrypt
: Interop.AppleCrypto.PAL_SymmetricOperation.Decrypt,
algorithm,
GetPalChainMode(algorithm, cipherMode, feedbackSizeInBytes),
Interop.AppleCrypto.PAL_PaddingMode.None,
pbKey,
key.Length,
pbIv,
Interop.AppleCrypto.PAL_SymmetricOptions.None,
out _cryptor,
out ccStatus);
}
ProcessInteropError(ret, ccStatus);
_canReset = cipherMode != CipherMode.CFB;
BlockSizeInBytes = blockSizeInBytes;
PaddingSizeInBytes = paddingSizeInBytes;
}