Java NativeCrypto.RSA_private_encrypt示例

  @Override
  protected byte[] engineDoFinal(byte[] input, int inputOffset, int inputLen)
      throws IllegalBlockSizeException, BadPaddingException {
    if (input != null) {
      engineUpdate(input, inputOffset, inputLen);
    }

    if (inputTooLarge) {
      throw new IllegalBlockSizeException("input must be under " + buffer.length + " bytes");
    }

    final byte[] tmpBuf;
    if (bufferOffset != buffer.length) {
      if (padding == NativeCrypto.RSA_NO_PADDING) {
        tmpBuf = new byte[buffer.length];
        System.arraycopy(buffer, 0, tmpBuf, buffer.length - bufferOffset, bufferOffset);
      } else {
        tmpBuf = Arrays.copyOf(buffer, bufferOffset);
      }
    } else {
      tmpBuf = buffer;
    }

    byte[] output = new byte[buffer.length];
    int resultSize;
    if (encrypting) {
      if (usingPrivateKey) {
        resultSize =
            NativeCrypto.RSA_private_encrypt(
                tmpBuf.length, tmpBuf, output, key.getPkeyContext(), padding);
      } else {
        resultSize =
            NativeCrypto.RSA_public_encrypt(
                tmpBuf.length, tmpBuf, output, key.getPkeyContext(), padding);
      }
    } else {
      try {
        if (usingPrivateKey) {
          resultSize =
              NativeCrypto.RSA_private_decrypt(
                  tmpBuf.length, tmpBuf, output, key.getPkeyContext(), padding);
        } else {
          resultSize =
              NativeCrypto.RSA_public_decrypt(
                  tmpBuf.length, tmpBuf, output, key.getPkeyContext(), padding);
        }
      } catch (SignatureException e) {
        IllegalBlockSizeException newE = new IllegalBlockSizeException();
        newE.initCause(e);
        throw newE;
      }
    }
    if (!encrypting && resultSize != output.length) {
      output = Arrays.copyOf(output, resultSize);
    }

    bufferOffset = 0;
    return output;
  }