前言

go 和java 的 AES CFB加密略有不同

java 版本

加密

    private static byte[] encrypt(byte[] encoded_payload, byte[] key) throws NoSuchPaddingException, NoSuchAlgorithmException, InvalidAlgorithmParameterException, InvalidKeyException, ShortBufferException, IllegalBlockSizeException, BadPaddingException {
    SecureRandom rand = new SecureRandom(); // or .getInstance* as you prefer


    SecretKeySpec key_spec = new SecretKeySpec(key, "AES");
    Cipher cipher = Cipher.getInstance("AES/CFB/NoPadding");

    int block_size = cipher.getBlockSize();

    byte[] buffer = new byte[block_size];
    rand.nextBytes(buffer);
    IvParameterSpec iv = new IvParameterSpec(buffer);

    buffer = Arrays.copyOf(buffer, block_size + encoded_payload.length);

    cipher.init(Cipher.ENCRYPT_MODE, key_spec, iv);

    cipher.doFinal(encoded_payload, 0, encoded_payload.length, buffer, block_size);
    return buffer;
}

解密

private static byte[] decrypt(byte[] payload, byte[] key) throws NoSuchPaddingException, NoSuchAlgorithmException, IllegalBlockSizeException, BadPaddingException, InvalidAlgorithmParameterException, InvalidKeyException {

    SecretKeySpec key_spec = new SecretKeySpec(key, "AES");
    Cipher cipher = Cipher.getInstance("AES/CFB/NoPadding");
    int block_size = cipher.getBlockSize();
    IvParameterSpec iv = new IvParameterSpec(Arrays.copyOf(payload, block_size));
    byte[] decryption_data = Arrays.copyOfRange(payload, block_size, payload.length);
    cipher.init(Cipher.DECRYPT_MODE, key_spec, iv);
    return cipher.doFinal(decryption_data);
}

go 版本

go加密

func Encrypt(payload []byte, key []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
  return nil, err
}
ciphertext := make([]byte, aes.BlockSize+len(payload))
iv := ciphertext[:aes.BlockSize]
if _, err := io.ReadFull(rand.Reader, iv); err != nil {
  return nil, err
}
cipher.NewCFBEncrypter(block, iv).XORKeyStream(ciphertext[aes.BlockSize:],
  payload)

return ciphertext, nil
}

go解密

func Decrypt(payload []byte, key []byte) ([]byte, error) {
 block, err := aes.NewCipher(key)
 if err != nil {
  return nil, err
 }
 if len(payload) < aes.BlockSize {
  return nil, errors.New("ciphertext too short")
 }
 iv := payload[:aes.BlockSize]
 payload = payload[aes.BlockSize:]
 cipher.NewCFBDecrypter(block, iv).XORKeyStream(payload, payload)
 return payload, nil
}