Package VaxTodo.Models

Class AES_GCM_Athentication

java.lang.Object

VaxTodo.Models.AES_GCM_Athentication

public class AES_GCM_Athentication
extends Object

Used for encrypting and decrypting string password with AES 256 Galois/Counter Mode and SHA256 as salt

Since:

v1.0.0

Authors:

Mohamed, Christian, Louis

Field Summary

Fields

Modifier and Type	Field	Description
private static final String	ENCRYPT_ALGO
private static final int	IV_LENGTH_BYTE
private static final int	SALT_LENGTH_BYTE
private static final int	TAG_LENGTH_BIT
private static final Charset	UTF_8

Constructor Summary

Constructors

Constructor	Description
AES_GCM_Athentication()

Method Summary

Modifier and Type	Method	Description
static String	decrypt(String strPasswd)
static String	encrypt(String strPasswd)	Take String password and returns encrypted string password
private static SecretKey	getAESKey(int keysize)
private static SecretKey	getAESKeyFromPassword(char[] password, byte[] salt)
private static byte[]	getRandomNonce(int numBytes)
private static String	hex(byte[] bytes)
private static String	hexWithBlockSize(byte[] bytes, int blockSize)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

ENCRYPT_ALGO

private static final String ENCRYPT_ALGO

See Also:

• Constant Field Values

TAG_LENGTH_BIT

private static final int TAG_LENGTH_BIT

See Also:

• Constant Field Values

IV_LENGTH_BYTE

private static final int IV_LENGTH_BYTE

See Also:

• Constant Field Values

SALT_LENGTH_BYTE

private static final int SALT_LENGTH_BYTE

See Also:

• Constant Field Values

UTF_8

private static final Charset UTF_8

Constructor Details

AES_GCM_Athentication

public AES_GCM_Athentication()

Method Details

encrypt

public static String encrypt(String strPasswd)
                      throws Exception

Take String password and returns encrypted string password

Parameters:

strPasswd - string password

Returns:

encrypted string password

Throws:

Exception - if password cannot be encrypted

decrypt

public static String decrypt(String strPasswd)
                      throws Exception

Throws:

Exception

getRandomNonce

private static byte[] getRandomNonce(int numBytes)

getAESKey

private static SecretKey getAESKey(int keysize)
                            throws NoSuchAlgorithmException

Throws:

NoSuchAlgorithmException

getAESKeyFromPassword

private static SecretKey getAESKeyFromPassword(char[] password,
 byte[] salt)
                                        throws NoSuchAlgorithmException,
InvalidKeySpecException

Throws:

NoSuchAlgorithmException

InvalidKeySpecException

hex

private static String hex(byte[] bytes)

hexWithBlockSize

private static String hexWithBlockSize(byte[] bytes,
 int blockSize)