Package org.kingdoms.utils.security

Class RSAAESHybrid

java.lang.Object

org.kingdoms.utils.security.RSAAESHybrid

public final class RSAAESHybrid
extends Object

Data -> AES -> RSA -> GZIP -> Base64 => Base64 -> GZIP -> RSA -> AES -> Data

Encrypts the main message using an AES symmetric key (unlimited length content encryption) then encrypts the AES key itself with an asymmetric RSA-2048 encryption. This causes to have two separate data, in order to send it, the two are merged together with the fixed encrypted AES key (256 bytes) at the beginning and the rest of the encrypted content. Then the resultant byte array is compressed with GZIP and the resultant compressed byte array is encoded in Base64 for easier ASCII data exchange. The same processed is reversed for decryption.

RSA is a fixed-length encryption. RSA-2048 can only encrypt 256 bytes at a time. Using multiple fixed RSA encryption blocks will decrease the security. So instead AES is used to encrypt variable-length data and the AES private fixed-length key itself is encrypted with RSA.

The private AES key for each server is generated per session (server start) and the public RSA key is provided below as a byte array.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	AES_CIPHER_ALGORITHM
static final String	RSA_CIPHER_ALGORITHM

Constructor Summary

Constructors

Constructor	Description
RSAAESHybrid()

Method Summary

Modifier and Type	Method	Description
static byte[]	decrypt0(PrivateKey privateKey, byte[] encryptedAESKey, byte[] encryptedData)
static Pair<String,Pair<byte[],byte[]>>	encrypt(byte[] inputData)	The key of the pair represents the compressed and Base64 encoded final value.
static Pair<byte[],byte[]>	encrypt0(byte[] content)
static void	generateAndPrintKeyPair()
static KeyPair	generateKeyPair()
static String	getMainMethod(String cipherAlgorithm)
static byte[]	merge(byte[] aes, byte[] content)
static Pair<byte[],byte[]>	splitString(String whole)

Methods inherited from class java.lang.Object

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

Field Details

AES_CIPHER_ALGORITHM

public static final String AES_CIPHER_ALGORITHM

See Also:

• Constant Field Values

RSA_CIPHER_ALGORITHM

public static final String RSA_CIPHER_ALGORITHM

See Also:

• Constant Field Values

Constructor Details

RSAAESHybrid

public RSAAESHybrid()

Method Details

getMainMethod

public static String getMainMethod(String cipherAlgorithm)

encrypt

public static Pair<String,Pair<byte[],byte[]>> encrypt(byte[] inputData)

The key of the pair represents the compressed and Base64 encoded final value.

merge

public static byte[] merge(byte[] aes,
 byte[] content)

splitString

public static Pair<byte[],byte[]> splitString(String whole)

encrypt0

public static Pair<byte[],byte[]> encrypt0(byte[] content)
                                    throws Exception

Throws:

Exception

decrypt0

public static byte[] decrypt0(PrivateKey privateKey,
 byte[] encryptedAESKey,
 byte[] encryptedData)
                       throws Exception

Throws:

Exception

generateKeyPair

public static KeyPair generateKeyPair()
                               throws NoSuchAlgorithmException,
NoSuchProviderException

Throws:

NoSuchAlgorithmException

NoSuchProviderException

generateAndPrintKeyPair

public static void generateAndPrintKeyPair()