com.grey.base.crypto

Class SymKey

java.lang.Object

com.grey.base.crypto.SymKey

public class SymKey
extends Object

This class supports generic secret-key encryption, as well as PBE (Password-Based Encryption) specifically.
Note 1: IVs allow you to reuse the same key for multiple messages. Salts prevent dictionary attacks on the password that derived the key
Note 2: In the JCE (Java Cryptography Extension), Generators are used to generate brand new objects (eg. keys), whereas Factories are used to convert data from one existing object type to another (eg. keys to key specs or vice versa).

Constructor Summary

Constructors

Constructor and Description
SymKey()

Method Summary

Modifier and Type	Method and Description
static Key	buildKey(String algname, byte[] enc, int off, int len)
static byte[]	decrypt(Key key, AlgorithmParameters algp, byte[] ciphertxt, int off, int len)
static byte[]	decryptPBE(char[] passwd, byte[] ciphertxt, int off, int len)
static byte[]	encrypt(Key key, AlgorithmParameters algp, byte[] plaintxt, int off, int len)
static byte[]	encryptPBE(char[] passwd, byte[] plaintxt, int off, int len)
static Key	generateKey(String algname, int keysize)

Methods inherited from class java.lang.Object

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

Constructor Detail

SymKey

public SymKey()

Method Detail

generateKey

public static Key generateKey(String algname,
                              int keysize)
                       throws NoSuchAlgorithmException

Throws:

NoSuchAlgorithmException

buildKey

public static Key buildKey(String algname,
                           byte[] enc,
                           int off,
                           int len)

encrypt

public static byte[] encrypt(Key key,
                             AlgorithmParameters algp,
                             byte[] plaintxt,
                             int off,
                             int len)
                      throws GeneralSecurityException

Throws:

GeneralSecurityException

decrypt

public static byte[] decrypt(Key key,
                             AlgorithmParameters algp,
                             byte[] ciphertxt,
                             int off,
                             int len)
                      throws GeneralSecurityException

Throws:

GeneralSecurityException

encryptPBE

public static byte[] encryptPBE(char[] passwd,
                                byte[] plaintxt,
                                int off,
                                int len)
                         throws GeneralSecurityException,
                                UnsupportedEncodingException

Throws:

GeneralSecurityException

UnsupportedEncodingException

decryptPBE

public static byte[] decryptPBE(char[] passwd,
                                byte[] ciphertxt,
                                int off,
                                int len)
                         throws GeneralSecurityException,
                                UnsupportedEncodingException

Throws:

GeneralSecurityException

UnsupportedEncodingException