public void decryptCEK()

in oss-20190517/src/main/java/com/aliyun/sdk/service/oss20190517/encryption/SimpleRSAEncryptionMaterials.java [212:242]

• 27 lines of code
• 4 McCabe index (conditional complexity)

    public void decryptCEK(ContentCryptoMaterial contentMaterial) {
        assertParameterNotNull(contentMaterial, "ContentCryptoMaterialRW");
        assertParameterNotNull(contentMaterial.getEncryptedCEK(), "ContentCryptoMaterialRW#getEncryptedCEK");
        assertParameterNotNull(contentMaterial.getEncryptedIV(), "ContentCryptoMaterialRW#getEncryptedIV");
        assertParameterNotNull(contentMaterial.getKeyWrapAlgorithm(), "ContentCryptoMaterialRW#getKeyWrapAlgorithm");

        if (!contentMaterial.getKeyWrapAlgorithm().equalsIgnoreCase(KEY_WRAP_ALGORITHM)) {
            throw new OSSClientException(
                    "Unrecognize your object key wrap algorithm: " + contentMaterial.getKeyWrapAlgorithm(), null);
        }

        try {
            KeyPair keyPair = findKeyPairByDescription(contentMaterial.getMaterialsDescription());
            if (keyPair == null) {
                Map.Entry<KeyPair, Map<String, String>> entry = getTailByReflection(keyPairDescMaterials);
                keyPair = entry.getKey();
            }

            Key key = keyPair.getPrivate();
            Cipher cipher = Cipher.getInstance(KEY_WRAP_ALGORITHM);
            cipher.init(Cipher.DECRYPT_MODE, key);
            byte[] cekBytes = cipher.doFinal(contentMaterial.getEncryptedCEK());
            byte[] iv = cipher.doFinal(contentMaterial.getEncryptedIV());
            SecretKey cek = new SecretKeySpec(cekBytes, "");

            contentMaterial.setCEK(cek);
            contentMaterial.setIV(iv);
        } catch (Exception e) {
            throw new OSSClientException("Unable to decrypt the secured content key and iv. " + e.getMessage(), e);
        }
    }