/// <summary>
/// Decrypt the encryptedData using the keyBits according the encrypt params.
/// </summary>
///
/// <param name="keyBits">The key value.</param>
/// <param name="encryptedData">The data to decrypt.</param>
/// <param name="params"></param>
/// <returns>The decrypted data.</returns>
public static Blob decrypt(Blob keyBits, Blob encryptedData,
EncryptParams paras)
{
if (paras.getAlgorithmType() == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesEcb)
{
Cipher cipher = javax.crypto.Cipher.getInstance("AES/ECB/PKCS5PADDING");
cipher.init(javax.crypto.Cipher.DECRYPT_MODE,
new SecretKeySpec(keyBits.getImmutableArray(), "AES"));
return(new Blob(cipher.doFinal(encryptedData.getImmutableArray()),
false));
}
else if (paras.getAlgorithmType() == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc)
{
if (paras.getInitialVector().size() != BLOCK_SIZE)
{
throw new Exception("incorrect initial vector size");
}
Cipher cipher_0 = javax.crypto.Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher_0.init(javax.crypto.Cipher.DECRYPT_MODE,
new SecretKeySpec(keyBits.getImmutableArray(), "AES"),
new IvParameterSpec(paras.getInitialVector()
.getImmutableArray()));
return(new Blob(cipher_0.doFinal(encryptedData.getImmutableArray()),
false));
}
else
{
throw new Exception("unsupported encryption mode");
}
}
/// <summary>
/// Encrypt the payload using the symmetric key according to params, and return
/// an EncryptedContent.
/// </summary>
///
/// <param name="payload">The data to encrypt.</param>
/// <param name="key">The key value.</param>
/// <param name="keyName">The key name for the EncryptedContent key locator.</param>
/// <param name="params">The parameters for encryption.</param>
/// <returns>A new EncryptedContent.</returns>
private static EncryptedContent encryptSymmetric(Blob payload, Blob key,
Name keyName, EncryptParams paras)
{
EncryptAlgorithmType algorithmType = paras.getAlgorithmType();
Blob initialVector = paras.getInitialVector();
KeyLocator keyLocator = new KeyLocator();
keyLocator.setType(net.named_data.jndn.KeyLocatorType.KEYNAME);
keyLocator.setKeyName(keyName);
if (algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc ||
algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesEcb)
{
if (algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc)
{
if (initialVector.size() != net.named_data.jndn.encrypt.algo.AesAlgorithm.BLOCK_SIZE)
{
throw new Exception("incorrect initial vector size");
}
}
Blob encryptedPayload = net.named_data.jndn.encrypt.algo.AesAlgorithm.encrypt(key, payload, paras);
EncryptedContent result = new EncryptedContent();
result.setAlgorithmType(algorithmType);
result.setKeyLocator(keyLocator);
result.setPayload(encryptedPayload);
result.setInitialVector(initialVector);
return(result);
}
else
{
throw new Exception("Unsupported encryption method");
}
}
/// <summary>
/// Decrypt the encryptedData using the keyBits according the encrypt params.
/// </summary>
///
/// <param name="keyBits">The key value.</param>
/// <param name="encryptedData">The data to decrypt.</param>
/// <param name="params"></param>
/// <returns>The decrypted data.</returns>
public static Blob decrypt(Blob keyBits, Blob encryptedData,
EncryptParams paras)
{
if (paras.getAlgorithmType() == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesEcb) {
Cipher cipher = javax.crypto.Cipher.getInstance("AES/ECB/PKCS5PADDING");
cipher.init(javax.crypto.Cipher.DECRYPT_MODE,
new SecretKeySpec(keyBits.getImmutableArray(), "AES"));
return new Blob(cipher.doFinal(encryptedData.getImmutableArray()),
false);
} else if (paras.getAlgorithmType() == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc) {
if (paras.getInitialVector().size() != BLOCK_SIZE)
throw new Exception("incorrect initial vector size");
Cipher cipher_0 = javax.crypto.Cipher.getInstance("AES/CBC/PKCS5PADDING");
cipher_0.init(javax.crypto.Cipher.DECRYPT_MODE,
new SecretKeySpec(keyBits.getImmutableArray(), "AES"),
new IvParameterSpec(paras.getInitialVector()
.getImmutableArray()));
return new Blob(cipher_0.doFinal(encryptedData.getImmutableArray()),
false);
} else
throw new Exception("unsupported encryption mode");
}
/// <summary>
/// Encrypt the payload using the symmetric key according to params, and return
/// an EncryptedContent.
/// </summary>
///
/// <param name="payload">The data to encrypt.</param>
/// <param name="key">The key value.</param>
/// <param name="keyName">The key name for the EncryptedContent key locator.</param>
/// <param name="params">The parameters for encryption.</param>
/// <returns>A new EncryptedContent.</returns>
private static EncryptedContent encryptSymmetric(Blob payload, Blob key,
Name keyName, EncryptParams paras)
{
EncryptAlgorithmType algorithmType = paras.getAlgorithmType();
Blob initialVector = paras.getInitialVector();
KeyLocator keyLocator = new KeyLocator();
keyLocator.setType(net.named_data.jndn.KeyLocatorType.KEYNAME);
keyLocator.setKeyName(keyName);
if (algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc
|| algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesEcb) {
if (algorithmType == net.named_data.jndn.encrypt.algo.EncryptAlgorithmType.AesCbc) {
if (initialVector.size() != net.named_data.jndn.encrypt.algo.AesAlgorithm.BLOCK_SIZE)
throw new Exception("incorrect initial vector size");
}
Blob encryptedPayload = net.named_data.jndn.encrypt.algo.AesAlgorithm.encrypt(key, payload, paras);
EncryptedContent result = new EncryptedContent();
result.setAlgorithmType(algorithmType);
result.setKeyLocator(keyLocator);
result.setPayload(encryptedPayload);
result.setInitialVector(initialVector);
return result;
} else
throw new Exception("Unsupported encryption method");
}
