Ejemplo n.º 1
0
        public void AgileEncryption()
        {
            int maxKeyLen = Cipher.GetMaxAllowedKeyLength("AES");

            Assume.That(maxKeyLen == 2147483647, "Please install JCE Unlimited Strength Jurisdiction Policy files for AES 256");

            FileStream       file = POIDataSamples.GetDocumentInstance().GetFile("bug53475-password-is-pass.docx");
            String           pass = "******";
            NPOIFSFileSystem nfs  = new NPOIFSFileSystem(file);

            // Check the encryption details
            EncryptionInfo infoExpected = new EncryptionInfo(nfs);
            Decryptor      decExpected  = Decryptor.GetInstance(infoExpected);
            bool           passed       = decExpected.VerifyPassword(pass);

            Assert.IsTrue(passed, "Unable to Process: document is encrypted");

            // extract the payload
            Stream is1 = decExpected.GetDataStream(nfs);

            byte[] payloadExpected = IOUtils.ToByteArray(is1);
            is1.Close();

            long decPackLenExpected = decExpected.GetLength();

            Assert.AreEqual(decPackLenExpected, payloadExpected.Length);

            is1 = nfs.Root.CreateDocumentInputStream(Decryptor.DEFAULT_POIFS_ENTRY);
            ///is1 = new BoundedInputStream(is1, is1.Available() - 16); // ignore pAdding block
            ///throw new NotImplementedException(BoundedInputStream);
            byte[] encPackExpected = IOUtils.ToByteArray(is1);
            is1.Close();

            // listDir(nfs.Root, "orig", "");

            nfs.Close();

            // check that same verifier/salt lead to same hashes
            byte[] verifierSaltExpected = infoExpected.Verifier.Salt;
            byte[] verifierExpected     = decExpected.GetVerifier();
            byte[] keySalt       = infoExpected.Header.KeySalt;
            byte[] keySpec       = decExpected.GetSecretKey().GetEncoded();
            byte[] integritySalt = decExpected.GetIntegrityHmacKey();
            // the hmacs of the file always differ, as we use PKCS5-pAdding to pad the bytes
            // whereas office just uses random bytes
            // byte integrityHash[] = d.IntegrityHmacValue;

            POIFSFileSystem fs         = new POIFSFileSystem();
            EncryptionInfo  infoActual = new EncryptionInfo(
                EncryptionMode.Agile
                , infoExpected.Verifier.CipherAlgorithm
                , infoExpected.Verifier.HashAlgorithm
                , infoExpected.Header.KeySize
                , infoExpected.Header.BlockSize
                , infoExpected.Verifier.ChainingMode
                );

            Encryptor e = Encryptor.GetInstance(infoActual);

            e.ConfirmPassword(pass, keySpec, keySalt, verifierExpected, verifierSaltExpected, integritySalt);

            Stream os = e.GetDataStream(fs);

            IOUtils.Copy(new MemoryStream(payloadExpected), os);
            os.Close();

            MemoryStream bos = new MemoryStream();

            fs.WriteFileSystem(bos);

            nfs        = new NPOIFSFileSystem(new MemoryStream(bos.ToArray()));
            infoActual = new EncryptionInfo(nfs.Root);
            Decryptor decActual = Decryptor.GetInstance(infoActual);

            passed = decActual.VerifyPassword(pass);
            Assert.IsTrue(passed, "Unable to Process: document is encrypted");

            // extract the payload
            is1 = decActual.GetDataStream(nfs);
            byte[] payloadActual = IOUtils.ToByteArray(is1);
            is1.Close();

            long decPackLenActual = decActual.GetLength();

            is1 = nfs.Root.CreateDocumentInputStream(Decryptor.DEFAULT_POIFS_ENTRY);
            ///is1 = new BoundedInputStream(is1, is1.Available() - 16); // ignore pAdding block
            ///throw new NotImplementedException(BoundedInputStream);
            byte[] encPackActual = IOUtils.ToByteArray(is1);
            is1.Close();

            // listDir(nfs.Root, "copy", "");

            nfs.Close();

            AgileEncryptionHeader aehExpected = (AgileEncryptionHeader)infoExpected.Header;
            AgileEncryptionHeader aehActual   = (AgileEncryptionHeader)infoActual.Header;

            CollectionAssert.AreEqual(aehExpected.GetEncryptedHmacKey(), aehActual.GetEncryptedHmacKey());
            Assert.AreEqual(decPackLenExpected, decPackLenActual);
            CollectionAssert.AreEqual(payloadExpected, payloadActual);
            CollectionAssert.AreEqual(encPackExpected, encPackActual);
        }