/** URL 编码, Encode默认为UTF-8. */
public static String urlEncode(String part) {
try {
return URLEncoder.encode(part, DEFAULT_URL_ENCODING);
} catch (UnsupportedEncodingException e) {
throw Exceptions.unchecked(e);
}
}
/** Hex解码. */
public static byte[] decodeHex(String input) {
try {
return Hex.decodeHex(input.toCharArray());
} catch (DecoderException e) {
throw Exceptions.unchecked(e);
}
}
/** 生成HMAC-SHA1密钥,返回字节数组,长度为160位(20字节). HMAC-SHA1算法对密钥无特殊要求, RFC2401建议最少长度为160位(20字节). */
public static byte[] generateHmacSha1Key() {
try {
KeyGenerator keyGenerator = KeyGenerator.getInstance(HMACSHA1);
keyGenerator.init(DEFAULT_HMACSHA1_KEYSIZE);
SecretKey secretKey = keyGenerator.generateKey();
return secretKey.getEncoded();
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
/**
* 使用HMAC-SHA1进行消息签名, 返回字节数组,长度为20字节.
*
* @param input 原始输入字符数组
* @param key HMAC-SHA1密钥
*/
public static byte[] hmacSha1(byte[] input, byte[] key) {
try {
SecretKey secretKey = new SecretKeySpec(key, HMACSHA1);
Mac mac = Mac.getInstance(HMACSHA1);
mac.init(secretKey);
return mac.doFinal(input);
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
/** 生成AES密钥,可选长度为128,192,256位. */
public static byte[] generateAesKey(int keysize) {
try {
KeyGenerator keyGenerator = KeyGenerator.getInstance(AES);
keyGenerator.init(keysize);
SecretKey secretKey = keyGenerator.generateKey();
return secretKey.getEncoded();
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
/**
* 使用AES加密或解密无编码的原始字节数组, 返回无编码的字节数组结果.
*
* @param input 原始字节数组
* @param key 符合AES要求的密钥
* @param mode Cipher.ENCRYPT_MODE 或 Cipher.DECRYPT_MODE
*/
private static byte[] aes(byte[] input, byte[] key, int mode) {
try {
SecretKey secretKey = new SecretKeySpec(key, AES);
Cipher cipher = Cipher.getInstance(AES);
cipher.init(mode, secretKey);
return cipher.doFinal(input);
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
private static byte[] digest(InputStream input, String algorithm) throws IOException {
try {
MessageDigest messageDigest = MessageDigest.getInstance(algorithm);
int bufferLength = 8 * 1024;
byte[] buffer = new byte[bufferLength];
int read = input.read(buffer, 0, bufferLength);
while (read > -1) {
messageDigest.update(buffer, 0, read);
read = input.read(buffer, 0, bufferLength);
}
return messageDigest.digest();
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}
/** 对字符串进行散列, 支持md5与sha1算法. */
private static byte[] digest(byte[] input, String algorithm, byte[] salt, int iterations) {
try {
MessageDigest digest = MessageDigest.getInstance(algorithm);
if (salt != null) {
digest.update(salt);
}
byte[] result = digest.digest(input);
for (int i = 1; i < iterations; i++) {
digest.reset();
result = digest.digest(result);
}
return result;
} catch (GeneralSecurityException e) {
throw Exceptions.unchecked(e);
}
}