/// <summary>
/// Encrypts the key data.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="passwordPrompt">The password prompt.</param>
/// <param name="iterationCount">The interation count.</param>
/// <returns></returns>
public static PbeKeyStore EncryptKeyData(byte[] key, Func <string> passwordPrompt, int iterationCount)
{
var pks = new PbeKeyStore()
{
Cipher = PbeKeyType.Aes128,
Hmac = PbeHashType.HmacSha1,
IterationCount = iterationCount,
Salt = new byte[16]
};
Secure.Random.NextBytes(pks.Salt);
var pbeKey = new PbeAesKey()
{
Size = 128
};
pbeKey.AesKeyBytes = pks.GetDerivedBytes(pbeKey.Size / 8, passwordPrompt);
pks.IV = pbeKey.IV;
using (pbeKey)
using (var ks = new ImportedKeySet(pbeKey, KeyPurpose.DecryptAndEncrypt, "Pbe key"))
using (var crypter = new Crypter(ks))
{
var data = crypter.Encrypt(key);
byte[] justciphertext = new byte[data.Length - Keyczar.HeaderLength];
Array.Copy(data, Keyczar.HeaderLength, justciphertext, 0, justciphertext.Length);
pks.Key = justciphertext;
}
return(pks);
}
/// <summary>
/// Decrypts the key data.
/// </summary>
/// <param name="passwordPrompt">The passsword prompt.</param>
/// <returns></returns>
public byte[] DecryptKeyData(Func <string> passwordPrompt)
{
var key = new PbeAesKey {
IV = IV
};
if (Cipher == PbeKeyType.Aes128)
{
key.Size = 128;
}
else
{
throw new InvalidKeySetException("Unknown Pbe Cipher");
}
key.AesKeyBytes = GetDerivedBytes(key.Size / 8, passwordPrompt);
using (key)
using (var ks = new ImportedKeySet(key, KeyPurpose.DecryptAndEncrypt, "Pbe key"))
using (var crypter = new Crypter(ks))
using (var memstream = new MemoryStream())
{
memstream.Write(Keyczar.FormatBytes, 0, Keyczar.FormatBytes.Length);
memstream.Write(new byte[Keyczar.KeyHashLength], 0, Keyczar.KeyHashLength);
memstream.Write(Key, 0, Key.Length);
return(crypter.Decrypt(memstream.ToArray()));
}
}
/// <summary>
/// Decrypts the key data.
/// </summary>
/// <param name="passwordPrompt">The passsword prompt.</param>
/// <returns></returns>
public byte[] DecryptKeyData(Func<string> passwordPrompt)
{
var key = new PbeAesKey {IV = IV};
if (Cipher == PbeKeyType.Aes128)
{
key.Size = 128;
}
else
{
throw new InvalidKeySetException("Unknown Pbe Cipher");
}
key.AesKeyBytes = GetDerivedBytes(key.Size/8, passwordPrompt);
using (key)
using (var ks = new ImportedKeySet(key, KeyPurpose.DecryptAndEncrypt, "Pbe key"))
using (var crypter = new Crypter(ks))
using (var memstream = new MemoryStream())
{
memstream.Write(Keyczar.FormatBytes, 0, Keyczar.FormatBytes.Length);
memstream.Write(new byte[Keyczar.KeyHashLength], 0, Keyczar.KeyHashLength);
memstream.Write(Key, 0, Key.Length);
return crypter.Decrypt(memstream.ToArray());
}
}
/// <summary>
/// Encrypts the key data.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="passwordPrompt">The password prompt.</param>
/// <param name="iterationCount">The interation count.</param>
/// <returns></returns>
public static PbeKeyStore EncryptKeyData(byte[] key, Func<string> passwordPrompt, int iterationCount)
{
var pks = new PbeKeyStore()
{
Cipher = PbeKeyType.Aes128,
Hmac = PbeHashType.HmacSha1,
IterationCount = iterationCount,
Salt = new byte[16]
};
Secure.Random.NextBytes(pks.Salt);
var pbeKey = new PbeAesKey() {Size = 128};
pbeKey.AesKeyBytes = pks.GetDerivedBytes(pbeKey.Size/8, passwordPrompt);
pks.IV = pbeKey.IV;
using (pbeKey)
using (var ks = new ImportedKeySet(pbeKey, KeyPurpose.DecryptAndEncrypt, "Pbe key"))
using (var crypter = new Crypter(ks))
{
var data = crypter.Encrypt(key);
byte[] justciphertext = new byte[data.Length - Keyczar.HeaderLength];
Array.Copy(data, Keyczar.HeaderLength, justciphertext, 0, justciphertext.Length);
pks.Key = justciphertext;
}
return pks;
}