private int writeEncryptedBlock()

in src/main/java/com/amazonaws/encryptionsdk/internal/BlockEncryptionHandler.java [143:176]

25 lines of code
2 McCabe index (conditional complexity)


  private int writeEncryptedBlock(
      final byte[] input, final int off, final int len, final byte[] out, final int outOff)
      throws BadCiphertextException {
    if (out.length == 0) {
      return 0;
    }

    int outLen = 0;
    final int seqNum = 1; // always 1 for single block case

    final byte[] contentAad =
        Utils.generateContentAad(messageId_, Constants.SINGLE_BLOCK_STRING_ID, seqNum, len);

    final byte[] nonce = getNonce();

    final byte[] encryptedBytes =
        new CipherHandler(encryptionKey_, Cipher.ENCRYPT_MODE, cryptoAlgo_)
            .cipherData(nonce, contentAad, input, off, len);

    // create the cipherblock headers now for the encrypted data
    final int encryptedContentLen = encryptedBytes.length - tagLenBytes_;
    final CipherBlockHeaders cipherBlockHeaders =
        new CipherBlockHeaders(nonce, encryptedContentLen);
    final byte[] cipherBlockHeaderBytes = cipherBlockHeaders.toByteArray();

    // assemble the headers and the encrypted bytes into a single block
    System.arraycopy(
        cipherBlockHeaderBytes, 0, out, outOff + outLen, cipherBlockHeaderBytes.length);
    outLen += cipherBlockHeaderBytes.length;
    System.arraycopy(encryptedBytes, 0, out, outOff + outLen, encryptedBytes.length);
    outLen += encryptedBytes.length;

    return outLen;
  }