Class Cipher

Definition

Namespace:

Tizen.Security.SecureRepository.Crypto

Assembly:

Tizen.Security.SecureRepository.dll

This class provides the methods for encrypting and decrypting data.

public class Cipher

Inheritance

object

Cipher

Constructors

Cipher(CipherParameters)

A constructor of Cipher that takes the algorithm specific parameters.

Declaration

public Cipher(CipherParameters parameters)

Parameters

Type	Name	Description
CipherParameters	parameters	The algorithm specific parameters.

Properties

Parameters

The algorithm specific parameters.

Declaration

public CipherParameters Parameters { get; }

Property Value

Type	Description
CipherParameters

Methods

Decrypt(string, string, byte[])

Decrypts data using the selected key and the algorithm.

Declaration

public byte[] Decrypt(string keyAlias, string password, byte[] cipherText)

Parameters

Type	Name	Description
string	keyAlias	Alias of the key to be used for decryption.
string	password	The password used in decrypting a key value. If password of policy is provided in SaveKey(), the same password should be provided.
byte[]	cipherText	Data to be decrypted (some algorithms may require additional information embedded in encrypted data.AES GCM is an example).

Returns

Type	Description
byte[]	Decrypted data.

Remarks

The key type specified by keyAlias should be compatible with the algorithm specified in Parameters.

Exceptions

Type	Condition
System.ArgumentNullException	The keyAlias or cipherText is null.
System.ArgumentException	The mandatory algorithm parameter is missing or invalid. The optional algorithm parameter is invalid.
System.InvalidOperationException	The key-protecting password isn't matched. The key does not exist with the keyAlias.

Encrypt(string, string, byte[])

Encrypts data using selected key and algorithm.

Declaration

public byte[] Encrypt(string keyAlias, string password, byte[] plainText)

Parameters

Type	Name	Description
string	keyAlias	Alias of the key to be used for encryption.
string	password	The password used in decrypting a key value. If password of policy is provided in SaveKey(), the same password should be provided.
byte[]	plainText	Data to be encrypted. In case of the AES algorithm, there are no restrictions on the size of data. For RSA, the size must be smaller or equal to (key_size_in bytes - 42). Example: For 1024 RSA key, the maximum data size is 1024/8 - 42 = 86.

Returns

Type	Description
byte[]	Encrypted data.

Remarks

The key type specified by the keyAlias should be compatible with the algorithm specified in Parameters.

Exceptions

Type	Condition
System.ArgumentNullException	The keyAlias or plainText is null.
System.ArgumentException	The mandatory algorithm parameter is missing or invalid. The optional algorithm parameter is invalid.
System.InvalidOperationException	The key-protecting password isn't matched. The key does not exist with the keyAlias.