工作中遇到nodejs端通過aes加密，安卓客戶端java解密，同樣nodejs也需要解密安卓客戶端加密過來的內容，發現兩個加密結果不一樣，查詢資料發現java端需要對金鑰再MD5加密一遍，以下是aes ecb加密的內容，如果是cbc也同樣需要對祕鑰MD5加密：

nodejs:

/**
 * aes加密
 * @param data
 * @param secretKey
 */
encryptUtils.aesEncrypt = function(data, secretKey) {
	var cipher = crypto.createCipher('aes-128-ecb',secretKey);
	return cipher.update(data,'utf8','hex') + cipher.final('hex');
}

/**
 * aes解密
 * @param data
 * @param secretKey
 * @returns {*}
 */
encryptUtils.aesDecrypt = function(data, secretKey) {
	var cipher = crypto.createDecipher('aes-128-ecb',secretKey);
	return cipher.update(data,'hex','utf8') + cipher.final('utf8');
}
 

package com.iofamily.util;

import java.security.MessageDigest;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * AES加密，與Nodejs 保持一致
 * @author lmiky
 * @date 2014-2-25
 */
public class AESForNodejs {
	public static final String DEFAULT_CODING = "utf-8";

	/**
	 * 解密
	 * @author lmiky
	 * @date 2014-2-25
	 * @param encrypted
	 * @param seed
	 * @return
	 * @throws Exception
	 */
	private static String decrypt(String encrypted, String seed) throws Exception {
		byte[] keyb = seed.getBytes(DEFAULT_CODING);
		MessageDigest md = MessageDigest.getInstance("MD5");
		byte[] thedigest = md.digest(keyb);
		SecretKeySpec skey = new SecretKeySpec(thedigest, "AES");
		Cipher dcipher = Cipher.getInstance("AES");
		dcipher.init(Cipher.DECRYPT_MODE, skey);

		byte[] clearbyte = dcipher.doFinal(toByte(encrypted));
		return new String(clearbyte);
	}

	/**
	 * 加密
	 * @author lmiky
	 * @date 2014-2-25
	 * @param content
	 * @param key
	 * @return
	 * @throws Exception
	 */
	public static String encrypt(String content, String key) throws Exception {
		byte[] input = content.getBytes(DEFAULT_CODING);
		
		MessageDigest md = MessageDigest.getInstance("MD5");
		byte[] thedigest = md.digest(key.getBytes(DEFAULT_CODING));
		SecretKeySpec skc = new SecretKeySpec(thedigest, "AES");
		Cipher cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
		cipher.init(Cipher.ENCRYPT_MODE, skc);
		
		byte[] cipherText = new byte[cipher.getOutputSize(input.length)];
		int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
		ctLength += cipher.doFinal(cipherText, ctLength);
	    	
		return parseByte2HexStr(cipherText);
	}
	
	/**
	 * 字串轉位元組陣列
	 * @author lmiky
	 * @date 2014-2-25
	 * @param hexString
	 * @return
	 */
	private static byte[] toByte(String hexString) {
		int len = hexString.length() / 2;
		byte[] result = new byte[len];
		for (int i = 0; i < len; i++) {
			result[i] = Integer.valueOf(hexString.substring(2 * i, 2 * i + 2), 16).byteValue();
		}
		return result;
	}
	
	/**
	 * 位元組轉16進位制陣列
	 * @author lmiky
	 * @date 2014-2-25
	 * @param buf
	 * @return
	 */
	private static String parseByte2HexStr(byte buf[]) {
		StringBuffer sb = new StringBuffer();
		for (int i = 0; i < buf.length; i++) {
			String hex = Integer.toHexString(buf[i] & 0xFF);
			if (hex.length() == 1) {
				hex = '0' + hex;
			}
			sb.append(hex);
		}
		return sb.toString();
	}
	
	public static void main(String[] args) throws Exception {
		System.out.println(AESForNodejs.encrypt("fsadfsdafsdafsdafsadfsadfsadf", "1234fghjnmlkiuhA"));
		System.out.println(AESForNodejs.decrypt("5b8e85b7a86ad15a275a7cb61fe4c0606005e8741f68797718a3e90d74b5092a", "1234fghjnmlkiuhA"));
	}
}