独自幸福快乐共振吸脂减肥有效的方法依依不舍孤独

鉴于rsa加密的重要性和相关源代码的匮乏，经过整理特此贴出。需要到下载r玩家也只需要在论坛用点积分兑换下。

import pher;

import curity.*;

import APublicKeySpec;

import APrivateKeySpec;

import validKeySpecException;

import APrivateKey;

import APublicKey;

import .*;

import gInteger;

/**

* RSA 工具类。提供加密，解密，生成密钥对等方法。

* 需要到下载r。

* @author xiaoyusong

* mail: xiaoyusong@

* msn:xiao_yu_song@

* @since

*

*/

public class RSAUtil {

/**

* 生成密钥对

* @return KeyPair

* @throws EncryptException

*/

public static KeyPair generateKeyPair() throws EncryptException {

try {

KeyPairGenerator keyPairGen = tInstance("RSA",

new uncyCastleProvider());

final int KEY_SIZE = 1024;//没什么好说的了，这个值关系到块加密的大小深入贯彻落实科学发展观，可以更改，但是不要太大，否则效率会低

itialize(KEY_SIZE, new SecureRandom());

KeyPair keyPair = nKeyPair();

return keyPair;

} catch (Exception e) {

throw new EncryptException(tMessage());

}

}

/**

* 生成公钥

* @param modulus

* @param publicExponent

* @return RSAPublicKey

* @throws EncryptException

*/

public static RSAPublicKey generateRSAPublicKey(byte[] modulus, byte[] publicExponent) throws EncryptException {

KeyFactory keyFac = null;

try {

keyFac = tInstance("RSA", new uncyCastleProvider());

} catch (NoSuchAlgorithmException ex) {

throw new EncryptException(tMessage());

}

RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(new BigInteger(modulus), new BigInteger(publicExponent));

try {

return (RSAPublicKey) neratePublic(pubKeySpec);

} catch (InvalidKeySpecException ex) {

throw new EncryptException(tMessage());

}

}

/**

* 生成私钥

* @param modulus

* @param privateExponent

* @return RSAPrivateKey

* @throws EncryptException

*/

public static RSAPrivateKey generateRSAPrivateKey(byte[] modulus, byte[] privateExponent) throws EncryptException {

KeyFactory keyFac = null;

try {

keyFac = tInstance("RSA", new uncyCastleProvider());

} catch (NoSuchAlgorithmException ex) {

throw new EncryptException(tMessage());

}

RSAPrivateKeySpec priKeySpec = new RSAPrivateKeySpec(new BigInteger(modulus), new BigInteger(privateExponent));

try {

return (RSAPrivateKey) neratePrivate(priKeySpec);

} catch (InvalidKeySpecException ex) {

throw new EncryptException(tMessage());

}

}

/**

* 加密

* @param key 加密的密钥

* @param data 待加密的明文数据

* @return 加密后的数据

* @throws EncryptException

*/

public static byte[] encrypt(Key key, byte[] data) throws EncryptException {

try {

Cipher cipher = tInstance("RSA", new uncyCastleProvider());

it(CRYPT_MODE, key);

int blockSize = tBlockSize();//获得加密块大小，如：加密前数据为128个byte，而key_size=1024 加密块大小为127 byte,加密后为128个byte;因此共有2个加密块，第一个127 byte第二个为1个byte

int outputSize = tOutputSize(ngth);//获得加密块加密后块大小

int leavedSize = ngth % blockSize;

int blocksSize = leavedSize != 0 ? ngth / blockSize + 1 : ngth / blockSize;

byte[] raw = new byte[outputSize * blocksSize];

int i = 0;

while (ngth - i * blockSize 0) {

if (ngth - i * blockSize blockSize)

Final(data, i * blockSize, blockSize, raw, i * outputSize);

else

Final(data, i * blockSize, ngth - i * blockSize, raw, i * outputSize);