/// <summary>
/// Initializes a new instance of the <see cref="SessionCrypter" /> class.
/// </summary>
/// <param name="keyEncrypter">The key encrypter.</param>
/// <param name="signer">The signer, optionally used to certify sender. (Equivialent to SignedSessionEncrypter)</param>
/// <param name="keySize">Size of the key.</param>
/// <param name="symmetricKeyType">Type of the symmetric key. (requires unofficial keypacker)</param>
/// <param name="keyPacker">The key packer.</param>
/// <exception cref="System.ArgumentException">Without a supplying a keypacker you may only use KeyType.AES;symmetricKeyType</exception>
public SessionCrypter(Encrypter keyEncrypter, AttachedSigner signer = null, int?keySize = null,
KeyType symmetricKeyType = null, ISessionKeyPacker keyPacker = null)
{
symmetricKeyType = symmetricKeyType ?? KeyType.Aes;
if (keyPacker == null && symmetricKeyType != KeyType.Aes)
{
throw new ArgumentException("Without a supplying a keypacker you may only use KeyType.AES",
"symmetricKeyType");
}
if (signer != null)
{
keyPacker = keyPacker ?? new NonceSignedSessionPacker();
}
keyPacker = keyPacker ?? new SimpleAesHmacSha1KeyPacker();
var key = Key.Generate(symmetricKeyType, keySize ?? symmetricKeyType.DefaultSize);
_keyset = new ImportedKeySet(key, KeyPurpose.DecryptAndEncrypt);
_crypter = new Crypter(_keyset);
_signer = signer;
byte[] packedKey;
var sessionPacker = keyPacker as IInteroperableSessionMaterialPacker;
if (sessionPacker == null)
{
packedKey = keyPacker.Pack(key);
}
else
{
var nonceSession = new NonceSessionMaterial((AesKey)key);
packedKey = sessionPacker.PackMaterial(nonceSession);
_nonce = nonceSession.Nonce.ToBytes();
}
_sessionMaterial = WebBase64.FromBytes(keyEncrypter.Encrypt(packedKey));
if (sessionPacker == null && _signer != null)
{
_sessionMaterial = WebBase64.FromBytes(_signer.Sign(_sessionMaterial.ToBytes()));
}
}
/// <summary>
/// Initializes a new instance of the <see cref="EncryptedKeySetWriter"/> class.
/// </summary>
/// <param name="writer">The writer.</param>
/// <param name="encrypter">The encrypter.</param>
public EncryptedKeySetWriter(IKeySetWriter writer, Encrypter encrypter)
{
_encrypter = encrypter;
_writer = writer;
}
public static Func <IKeySetWriter, EncryptedKeySetWriter> Creator(Encrypter encrypter)
{
return(writer => new EncryptedKeySetWriter(writer, encrypter));
}
