密码加密

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import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import java.util.Arrays;

import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;

public class PasswordEncryptionService {

	public boolean authenticate(String attemptedPassword,
			byte[] encryptedPassword, byte[] salt)
			throws NoSuchAlgorithmException, InvalidKeySpecException {
		// Encrypt the clear-text password using the same salt that was used to
		// encrypt the original password
		byte[] encryptedAttemptedPassword = getEncryptedPassword(
				attemptedPassword, salt);

		// Authentication succeeds if encrypted password that the user entered
		// is equal to the stored hash
		return Arrays.equals(encryptedPassword, encryptedAttemptedPassword);
	}

	public byte[] getEncryptedPassword(String password, byte[] salt)
			throws NoSuchAlgorithmException, InvalidKeySpecException {
		// PBKDF2 with SHA-1 as the hashing algorithm. Note that the NIST
		// specifically names SHA-1 as an acceptable hashing algorithm for
		// PBKDF2
		String algorithm = "PBKDF2WithHmacSHA1";
		// SHA-1 generates 160 bit hashes, so that's what makes sense here
		int derivedKeyLength = 160;
		// Pick an iteration count that works for you. The NIST recommends at
		// least 1,000 iterations:
		// http://csrc.nist.gov/publications/nistpubs/800-132/nist-sp800-132.pdf
		// iOS 4.x reportedly uses 10,000:
		// http://blog.crackpassword.com/2010/09/smartphone-forensics-cracking-blackberry-backup-passwords/
		int iterations = 20000;

		KeySpec spec = new PBEKeySpec(password.toCharArray(), salt, iterations,
				derivedKeyLength);

		SecretKeyFactory f = SecretKeyFactory.getInstance(algorithm);

		return f.generateSecret(spec).getEncoded();
	}

	public byte[] generateSalt() throws NoSuchAlgorithmException {
		// VERY important to use SecureRandom instead of just Random
		SecureRandom random = SecureRandom.getInstance("SHA1PRNG");

		// Generate a 8 byte (64 bit) salt as recommended by RSA PKCS5
		byte[] salt = new byte[8];
		random.nextBytes(salt);

		return salt;
	}
}

 

public static void main(String[] args) {
		PasswordEncryptionService passwordEncryptionService = new PasswordEncryptionService();
		String password = "testTest";
		try {
			//生成salt，可保存到数据库用于验证
			byte[] salt = passwordEncryptionService.generateSalt();
			//根据salt加密的密码，可保存到数据库用于验证
			byte[] encryptedPassword = passwordEncryptionService.getEncryptedPassword(password, salt);
			//验证密码，根据上面保存的salt，encryptedPassword进行密码验证
			boolean bl = passwordEncryptionService.authenticate(password, encryptedPassword, salt);
			
			System.out.println(bl);
		} catch (NoSuchAlgorithmException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (InvalidKeySpecException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}