Package de.mhus.lib.core.crypt

Class MBouncy

java.lang.Object

de.mhus.lib.core.crypt.MBouncy

public class MBouncy
extends Object

This utility uses explicit bouncy castle methods for cryptography. It depends on BC but not JCE. For some compatibility reasons it makes sense to use BC instead of JCE (e.g. open jdk on not common environments / hardware JCE is not available).

Author:

mikehummel

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MBouncy.ECC_SPEC
static class	MBouncy.RSA_KEY_SIZE

Field Summary

Fields

Modifier and Type	Field	Description
protected static String	ALGORITHM_AES
protected static String	ALGORITHM_RSA
protected static String	PROVIDER
static MBouncy.RSA_KEY_SIZE	RSA_KEY_SIZE_DEFAULT
protected static String	TRANSFORMATION

Constructor Summary

Constructors

Constructor	Description
MBouncy()

Method Summary

Modifier and Type	Method	Description
static byte[]	createRandom(int size)	Create a array of 'size' with random content.
static String	createSignature(PrivateKey key, InputStream is)
static String	createSignature(PrivateKey key, String in)
static byte[]	decodeBase64(String text)	Decode Base64 encoded string to bytes
static byte[]	decryptAes(byte[] key, byte[] encrypted)	Decrypt a encrypted byte array.
static String	decryptAes(byte[] key, String encrypted)	Decrypt a base64 encoded string and return the ariginal string.
static byte[]	decryptRsa(byte[] text, PrivateKey key, MBouncy.RSA_KEY_SIZE size)	Decrypt an encrypted block.
static byte[]	decryptRsa117(byte[] text, PrivateKey key)	Decrypt a single rsa block (128 bytes for 1024 bits, 256 for 2048 bits ...) with a result of maximal 117 bytes.
static String	decryptRsa117(String text, PrivateKey key)	Decrypt a single base64 encrypted byte block.
static String	encodeBase64(byte[] bytes)	encode bytes with base64 algorithm.
static byte[]	encryptAes(byte[] key, byte[] data)	Encrypt the data using symmetric AES.
static String	encryptAes(byte[] key, String data)	Encrypt the String using UTF8 encoding and return a base64 encoded string.
static byte[]	encryptRsa(byte[] text, PublicKey key)	Encrypt a unlimited amount of bytes with rsa.
static byte[]	encryptRsa117(byte[] text, PublicKey key)	Encrypt one block with maximal 117 bytes (block size for 1024).
static String	encryptRsa117(String text, PublicKey key)	Encrypt a single block with max 117 bytes as base64 string.
static Key	generateAesKeySpec(byte[] key)	Creates a key object from bytes.
static KeyPair	generateEccKey(MBouncy.ECC_SPEC spec)
static KeyPair	generateRsaKey(MBouncy.RSA_KEY_SIZE size)	Generate a RSA key pair with 1024 bits.
static PrivateKey	getPrivateKey(String key)	Transforms a string encoded private key into a private key object
static String	getPrivateKey(KeyPair key)	Returns the private key of a key pair as string
static PemBlock	getPrivatePem(KeyPair pair)
static PemBlock	getPrivatePem(PrivateKey key)
static PublicKey	getPublicKey(String key)	Transform a string encoded public key to a public key object.
static String	getPublicKey(KeyPair key)	Returns the public key of a key pair as string
static PemBlock	getPublicPem(KeyPair pair)
static PemBlock	getPublicPem(PublicKey key)
static KeyPair	getRsaKeyFromPool()	Generating RSA keys needs a lot of resources (ca 100ms per key).
static void	init()
static boolean	validateSignature(PublicKey key, InputStream is, String sign)
static boolean	validateSignature(PublicKey key, String in, String sign)

Methods inherited from class java.lang.Object

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

Field Detail

ALGORITHM_RSA

protected static final String ALGORITHM_RSA

See Also:

Constant Field Values

PROVIDER

protected static final String PROVIDER

See Also:

Constant Field Values

TRANSFORMATION

protected static final String TRANSFORMATION

See Also:

Constant Field Values

ALGORITHM_AES

protected static final String ALGORITHM_AES

See Also:

Constant Field Values

RSA_KEY_SIZE_DEFAULT

public static final MBouncy.RSA_KEY_SIZE RSA_KEY_SIZE_DEFAULT

Constructor Detail

MBouncy

public MBouncy()

Method Detail

init

public static void init()

generateRsaKey

public static KeyPair generateRsaKey(MBouncy.RSA_KEY_SIZE size)
                              throws NoSuchAlgorithmException,
                                     NoSuchProviderException

Generate a RSA key pair with 1024 bits.

Parameters:

size -

Returns:

The key pair

Throws:

NoSuchAlgorithmException

NoSuchProviderException

getPublicKey

public static PublicKey getPublicKey(String key)

Transform a string encoded public key to a public key object.

Parameters:

key - Public Key as string

Returns:

Public Key as object

getPrivateKey

public static PrivateKey getPrivateKey(String key)

Transforms a string encoded private key into a private key object

Parameters:

key - Private Key as string

Returns:

Private Key as object

getPublicKey

public static String getPublicKey(KeyPair key)

Returns the public key of a key pair as string

Parameters:

key -

Returns:

Public Key as string

getPrivateKey

public static String getPrivateKey(KeyPair key)

Returns the private key of a key pair as string

Parameters:

key -

Returns:

Private Key as string

getPrivatePem

public static PemBlock getPrivatePem(KeyPair pair)

getPrivatePem

public static PemBlock getPrivatePem(PrivateKey key)

getPublicPem

public static PemBlock getPublicPem(KeyPair pair)

getPublicPem

public static PemBlock getPublicPem(PublicKey key)

encryptRsa117

public static byte[] encryptRsa117(byte[] text,
                                   PublicKey key)
                            throws Exception

Encrypt one block with maximal 117 bytes (block size for 1024). Optimized for one block step.

Parameters:

text -

key -

Returns:

The encrypted block (128 bytes for 1024 bits, 256 bytes for 2048 bits ...)

Throws:

Exception

encryptRsa

public static byte[] encryptRsa(byte[] text,
                                PublicKey key)
                         throws Exception

Encrypt a unlimited amount of bytes with rsa.

Parameters:

text -

key -

Returns:

encrypted bytes

Throws:

Exception

decryptRsa

public static byte[] decryptRsa(byte[] text,
                                PrivateKey key,
                                MBouncy.RSA_KEY_SIZE size)
                         throws Exception

Decrypt an encrypted block.

Parameters:

text -

key -

size -

Returns:

decrypted data

Throws:

Exception

encryptRsa117

public static String encryptRsa117(String text,
                                   PublicKey key)
                            throws Exception

Encrypt a single block with max 117 bytes as base64 string. Optimized for one block encryption. The text will be encoded with UTF8.

Parameters:

text - UTF8 Text

key -

Returns:

encrypted string

Throws:

Exception

decryptRsa117

public static byte[] decryptRsa117(byte[] text,
                                   PrivateKey key)
                            throws Exception

Decrypt a single rsa block (128 bytes for 1024 bits, 256 for 2048 bits ...) with a result of maximal 117 bytes. Optimized for a single block step.

Parameters:

text -

key -

Returns:

decrypted string

Throws:

Exception

decryptRsa117

public static String decryptRsa117(String text,
                                   PrivateKey key)
                            throws Exception

Decrypt a single base64 encrypted byte block. The text will decoded with UTF8.

Parameters:

text -

key -

Returns:

decrypted string

Throws:

Exception

encodeBase64

public static String encodeBase64(byte[] bytes)

encode bytes with base64 algorithm.

Parameters:

bytes -

Returns:

Base64 encoded string

decodeBase64

public static byte[] decodeBase64(String text)

Decode Base64 encoded string to bytes

Parameters:

text -

Returns:

original bytes

createRandom

public static byte[] createRandom(int size)

Create a array of 'size' with random content.

Parameters:

size -

Returns:

random content

encryptAes

public static byte[] encryptAes(byte[] key,
                                byte[] data)

Encrypt the data using symmetric AES.

Parameters:

key - The key with 16, 24 or 32 bytes.

data -

Returns:

Encoded data

encryptAes

public static String encryptAes(byte[] key,
                                String data)

Encrypt the String using UTF8 encoding and return a base64 encoded string.

Parameters:

key -

data -

Returns:

Base64 encoded encrypted string

generateAesKeySpec

public static Key generateAesKeySpec(byte[] key)

Creates a key object from bytes.

Parameters:

key -

Returns:

The bytes key as object

decryptAes

public static byte[] decryptAes(byte[] key,
                                byte[] encrypted)

Decrypt a encrypted byte array.

Parameters:

key -

encrypted -

Returns:

original bytes

decryptAes

public static String decryptAes(byte[] key,
                                String encrypted)

Decrypt a base64 encoded string and return the ariginal string. String encoding is UTF8.

Parameters:

key -

encrypted -

Returns:

The original string

getRsaKeyFromPool

public static KeyPair getRsaKeyFromPool()

Generating RSA keys needs a lot of resources (ca 100ms per key). Therefore you can use a keypool. The keypool will regularly renew the keys.

Returns:

A key from the pool

generateEccKey

public static KeyPair generateEccKey(MBouncy.ECC_SPEC spec)

validateSignature

public static boolean validateSignature(PublicKey key,
                                        String in,
                                        String sign)

validateSignature

public static boolean validateSignature(PublicKey key,
                                        InputStream is,
                                        String sign)

createSignature

public static String createSignature(PrivateKey key,
                                     String in)

createSignature

public static String createSignature(PrivateKey key,
                                     InputStream is)