背景

公司PHP开发对接一个Java项目接口，接口返回数据有用DESede/ECB/PKCS5Padding加密，并且key也使用了SHA1PRNG加密了，网上找了各种办法都不能解密，耗了一两天的时间，一度怀疑人生……

JAVA代码

public class DESUtil {private static final String KEY_ALGORITHM = "DESede";private static final String DEFAULT_CIPHER_ALGORITHM = "DESede/ECB/PKCS5Padding";/* DES加密 */public static String encrypt(String content, final String key) {try {Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);byte[] byteContent = content.getBytes(StandardCharsets.UTF_8.name());cipher.init(Cipher.ENCRYPT_MODE, getSecretKey(key));byte[] result = cipher.doFinal(byteContent);return Base64.encodeBase64String(result);} catch (Exception ex) {log.error("【DES加密失败】:", ex);}return null;}/* DES解密 */public static String decrypt(String content, final String key) {try {Cipher cipher = Cipher.getInstance(DEFAULT_CIPHER_ALGORITHM);cipher.init(Cipher.DECRYPT_MODE, getSecretKey(key));byte[] result = cipher.doFinal(Base64.decodeBase64(content));return new String(result, StandardCharsets.UTF_8.name());} catch (Exception ex) {log.error("【DES解密失败】:", ex);}return null;}public static SecretKeySpec getSecretKey(final String key) {KeyGenerator kg = null;try {kg = KeyGenerator.getInstance(KEY_ALGORITHM);SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");secureRandom.setSeed(key.getBytes(StandardCharsets.UTF_8.name()));kg.init(secureRandom);SecretKey secretKey = kg.generateKey();return new SecretKeySpec(secretKey.getEncoded(), KEY_ALGORITHM);} catch (NoSuchAlgorithmException ex) {log.error("【DES生成秘钥失败】:", ex);} catch (UnsupportedEncodingException e) {log.error("【DES生成秘钥失败】:", e);}return null;}
}

解决思路

终于找到了一个类似问题，可是要会员才能看，作为一名穷DS,哪有这么富有，灵机一动在某鱼花了1大洋看了解决思路，果然是金钱的力量，功夫不负有心人啊，终于寻到stackoverflow有个类似问题。

上面Java代码中的secretKey变量的比特值，使用Base64Utils.encode后得到base64字符串
然后在php中使用base64_decode解码串，得到密钥key

PHP解密

/* 3DES解密 */public function desDecrypt($content) {$key=$this->config['desKey'];$key=base64_decode($key);$content = base64_decode($content);// 解密数据$plaintext = openssl_decrypt($content, 'DES-EDE3', $key, OPENSSL_RAW_DATA);return $plaintext;}