/// <summary>
/// Initializes a new instance of the <see cref="SymmetricCryptographicKey" /> class.
/// </summary>
/// <param name="provider">The provider that created this instance.</param>
/// <param name="name">The name of the base algorithm to use.</param>
/// <param name="mode">The algorithm's mode (i.e. streaming or some block mode).</param>
/// <param name="padding">The padding to use.</param>
/// <param name="keyMaterial">The key.</param>
internal SymmetricCryptographicKey(SymmetricKeyAlgorithmProvider provider, SymmetricAlgorithmName name, SymmetricAlgorithmMode mode, SymmetricAlgorithmPadding padding, byte[] keyMaterial)
{
Requires.NotNull(provider, nameof(provider));
Requires.NotNull(keyMaterial, nameof(keyMaterial));
if (name == SymmetricAlgorithmName.Aes && mode == SymmetricAlgorithmMode.Ccm && padding == SymmetricAlgorithmPadding.None)
{
// On Android encryption misbehaves causing our unit tests to fail.
throw new NotSupportedException();
}
this.provider = provider;
this.Name = name;
this.Mode = mode;
this.Padding = padding;
this.key = new SecretKeySpec(keyMaterial, this.Name.GetString());
this.KeySize = keyMaterial.Length * 8;
}
/// <summary>
/// Initializes a new instance of the <see cref="SymmetricCryptographicKey" /> class.
/// </summary>
/// <param name="provider">The provider that created this instance.</param>
/// <param name="name">The name of the base algorithm to use.</param>
/// <param name="mode">The algorithm's mode (i.e. streaming or some block mode).</param>
/// <param name="padding">The padding to use.</param>
/// <param name="keyMaterial">The key.</param>
internal SymmetricCryptographicKey(SymmetricKeyAlgorithmProvider provider, SymmetricAlgorithmName name, SymmetricAlgorithmMode mode, SymmetricAlgorithmPadding padding, byte[] keyMaterial)
{
Requires.NotNull(provider, nameof(provider));
Requires.NotNull(keyMaterial, nameof(keyMaterial));
if (name == SymmetricAlgorithmName.Aes && mode == SymmetricAlgorithmMode.Ccm && padding == SymmetricAlgorithmPadding.None)
{
// On Android encryption misbehaves causing our unit tests to fail.
throw new NotSupportedException();
}
this.provider = provider;
this.Name = name;
this.Mode = mode;
this.Padding = padding;
this.key = new SecretKeySpec(keyMaterial, this.Name.GetString());
this.KeySize = keyMaterial.Length * 8;
}
/// <summary>
/// Initializes a new instance of the <see cref="SymmetricCryptographicKey" /> class.
/// </summary>
/// <param name="keyMaterial">The symmetric key.</param>
/// <param name="symmetricAlgorithmProvider">The symmetric algorithm of the provider creating this key.</param>
internal SymmetricCryptographicKey(byte[] keyMaterial, SymmetricKeyAlgorithmProvider symmetricAlgorithmProvider)
{
Requires.NotNullOrEmpty(keyMaterial, nameof(keyMaterial));
Requires.NotNull(symmetricAlgorithmProvider, nameof(symmetricAlgorithmProvider));
this.symmetricAlgorithmProvider = symmetricAlgorithmProvider;
// Copy the key material so our caller can reuse their buffer.
this.keyMaterial = new byte[keyMaterial.Length];
Array.Copy(keyMaterial, this.keyMaterial, keyMaterial.Length);
this.Name = symmetricAlgorithmProvider.Name;
this.Mode = symmetricAlgorithmProvider.Mode;
this.Padding = symmetricAlgorithmProvider.Padding;
if (this.Padding == SymmetricAlgorithmPadding.PKCS7)
{
this.flags |= BCryptEncryptFlags.BCRYPT_BLOCK_PADDING;
}
}
/// <summary>
/// Initializes a new instance of the <see cref="SymmetricCryptographicKey" /> class.
/// </summary>
/// <param name="keyMaterial">The symmetric key.</param>
/// <param name="symmetricAlgorithmProvider">The symmetric algorithm of the provider creating this key.</param>
internal SymmetricCryptographicKey(byte[] keyMaterial, SymmetricKeyAlgorithmProvider symmetricAlgorithmProvider)
{
Requires.NotNullOrEmpty(keyMaterial, nameof(keyMaterial));
Requires.NotNull(symmetricAlgorithmProvider, nameof(symmetricAlgorithmProvider));
this.symmetricAlgorithmProvider = symmetricAlgorithmProvider;
// Copy the key material so our caller can reuse their buffer.
this.keyMaterial = new byte[keyMaterial.Length];
Array.Copy(keyMaterial, this.keyMaterial, keyMaterial.Length);
this.Name = symmetricAlgorithmProvider.Name;
this.Mode = symmetricAlgorithmProvider.Mode;
this.Padding = symmetricAlgorithmProvider.Padding;
if (this.Padding == SymmetricAlgorithmPadding.PKCS7)
{
this.flags |= BCryptEncryptFlags.BCRYPT_BLOCK_PADDING;
}
}
/// <summary>
/// Initializes a new instance of the <see cref="CryptographicKey" /> class.
/// </summary>
/// <param name="key">The WinRT cryptographic key.</param>
/// <param name="symmetricAlgorithmProvider">The symmetric algorithm of the provider creating this key.</param>
/// <param name="canExportPrivateKey">
/// A value indicating whether <see cref="Export(CryptographicPrivateKeyBlobType)"/>
/// can be expected to work.
/// </param>
internal CryptographicKey(Platform.CryptographicKey key, SymmetricKeyAlgorithmProvider symmetricAlgorithmProvider, bool canExportPrivateKey)
: this(key, canExportPrivateKey)
{
this.symmetricAlgorithmProvider = symmetricAlgorithmProvider;
}
/// <summary>
/// Checks whether the given length is a valid one for an input buffer to the symmetric algorithm.
/// </summary>
/// <param name="lengthInBytes">The length of the input buffer in bytes.</param>
/// <param name="cipher">The cipher that dictates the allowed input sizes.</param>
/// <returns><c>true</c> if the size is allowed; <c>false</c> otherwise.</returns>
private bool IsValidInputSize(int lengthInBytes, Cipher cipher)
{
int blockSizeInBytes = SymmetricKeyAlgorithmProvider.GetBlockSize(this.Mode, cipher);
return(lengthInBytes % blockSizeInBytes == 0);
}
