Example #1
0
        /// <exception cref="IOException"></exception>
        public TlsNullCipher(TlsContext context, IDigest clientWriteDigest, IDigest serverWriteDigest)
        {
            if ((clientWriteDigest == null) != (serverWriteDigest == null))
            {
                throw new TlsFatalAlert(AlertDescription.internal_error);
            }

            this.context = context;

            TlsMac clientWriteMac = null, serverWriteMac = null;

            if (clientWriteDigest != null)
            {
                int key_block_size = clientWriteDigest.GetDigestSize()
                                     + serverWriteDigest.GetDigestSize();
                byte[] key_block = TlsUtilities.CalculateKeyBlock(context, key_block_size);

                int offset = 0;

                clientWriteMac = new TlsMac(context, clientWriteDigest, key_block, offset,
                                            clientWriteDigest.GetDigestSize());
                offset += clientWriteDigest.GetDigestSize();

                serverWriteMac = new TlsMac(context, serverWriteDigest, key_block, offset,
                                            serverWriteDigest.GetDigestSize());
                offset += serverWriteDigest.GetDigestSize();

                if (offset != key_block_size)
                {
                    throw new TlsFatalAlert(AlertDescription.internal_error);
                }
            }

            if (context.IsServer)
            {
                writeMac = serverWriteMac;
                readMac  = clientWriteMac;
            }
            else
            {
                writeMac = clientWriteMac;
                readMac  = serverWriteMac;
            }
        }
Example #2
0
        /// <exception cref="IOException"></exception>
        public TlsStreamCipher(TlsContext context, IStreamCipher clientWriteCipher,
                               IStreamCipher serverWriteCipher, IDigest clientWriteDigest, IDigest serverWriteDigest,
                               int cipherKeySize, bool usesNonce)
        {
            bool isServer = context.IsServer;

            this.context   = context;
            this.usesNonce = usesNonce;

            this.encryptCipher = clientWriteCipher;
            this.decryptCipher = serverWriteCipher;

            int key_block_size = (2 * cipherKeySize) + clientWriteDigest.GetDigestSize()
                                 + serverWriteDigest.GetDigestSize();

            byte[] key_block = TlsUtilities.CalculateKeyBlock(context, key_block_size);

            int offset = 0;

            // Init MACs
            TlsMac clientWriteMac = new TlsMac(context, clientWriteDigest, key_block, offset,
                                               clientWriteDigest.GetDigestSize());

            offset += clientWriteDigest.GetDigestSize();
            TlsMac serverWriteMac = new TlsMac(context, serverWriteDigest, key_block, offset,
                                               serverWriteDigest.GetDigestSize());

            offset += serverWriteDigest.GetDigestSize();

            // Build keys
            KeyParameter clientWriteKey = new KeyParameter(key_block, offset, cipherKeySize);

            offset += cipherKeySize;
            KeyParameter serverWriteKey = new KeyParameter(key_block, offset, cipherKeySize);

            offset += cipherKeySize;

            if (offset != key_block_size)
            {
                throw new TlsFatalAlert(AlertDescription.internal_error);
            }

            ICipherParameters encryptParams, decryptParams;

            if (isServer)
            {
                this.writeMac      = serverWriteMac;
                this.readMac       = clientWriteMac;
                this.encryptCipher = serverWriteCipher;
                this.decryptCipher = clientWriteCipher;
                encryptParams      = serverWriteKey;
                decryptParams      = clientWriteKey;
            }
            else
            {
                this.writeMac      = clientWriteMac;
                this.readMac       = serverWriteMac;
                this.encryptCipher = clientWriteCipher;
                this.decryptCipher = serverWriteCipher;
                encryptParams      = clientWriteKey;
                decryptParams      = serverWriteKey;
            }

            if (usesNonce)
            {
                byte[] dummyNonce = new byte[8];
                encryptParams = new ParametersWithIV(encryptParams, dummyNonce);
                decryptParams = new ParametersWithIV(decryptParams, dummyNonce);
            }

            this.encryptCipher.Init(true, encryptParams);
            this.decryptCipher.Init(false, decryptParams);
        }
Example #3
0
        /// <exception cref="IOException"></exception>
        public TlsBlockCipher(TlsContext context, IBlockCipher clientWriteCipher, IBlockCipher serverWriteCipher,
                              IDigest clientWriteDigest, IDigest serverWriteDigest, int cipherKeySize)
        {
            this.context = context;

            this.randomData = new byte[256];
            context.NonceRandomGenerator.NextBytes(randomData);

            this.useExplicitIV  = TlsUtilities.IsTlsV11(context);
            this.encryptThenMac = context.SecurityParameters.encryptThenMac;

            int key_block_size = (2 * cipherKeySize) + clientWriteDigest.GetDigestSize()
                                 + serverWriteDigest.GetDigestSize();

            // From TLS 1.1 onwards, block ciphers don't need client_write_IV
            if (!useExplicitIV)
            {
                key_block_size += clientWriteCipher.GetBlockSize() + serverWriteCipher.GetBlockSize();
            }

            byte[] key_block = TlsUtilities.CalculateKeyBlock(context, key_block_size);

            int offset = 0;

            TlsMac clientWriteMac = new TlsMac(context, clientWriteDigest, key_block, offset,
                                               clientWriteDigest.GetDigestSize());

            offset += clientWriteDigest.GetDigestSize();
            TlsMac serverWriteMac = new TlsMac(context, serverWriteDigest, key_block, offset,
                                               serverWriteDigest.GetDigestSize());

            offset += serverWriteDigest.GetDigestSize();

            KeyParameter client_write_key = new KeyParameter(key_block, offset, cipherKeySize);

            offset += cipherKeySize;
            KeyParameter server_write_key = new KeyParameter(key_block, offset, cipherKeySize);

            offset += cipherKeySize;

            byte[] client_write_IV, server_write_IV;
            if (useExplicitIV)
            {
                client_write_IV = new byte[clientWriteCipher.GetBlockSize()];
                server_write_IV = new byte[serverWriteCipher.GetBlockSize()];
            }
            else
            {
                client_write_IV = Arrays.CopyOfRange(key_block, offset, offset + clientWriteCipher.GetBlockSize());
                offset         += clientWriteCipher.GetBlockSize();
                server_write_IV = Arrays.CopyOfRange(key_block, offset, offset + serverWriteCipher.GetBlockSize());
                offset         += serverWriteCipher.GetBlockSize();
            }

            if (offset != key_block_size)
            {
                throw new TlsFatalAlert(AlertDescription.internal_error);
            }

            ICipherParameters encryptParams, decryptParams;

            if (context.IsServer)
            {
                this.mWriteMac     = serverWriteMac;
                this.mReadMac      = clientWriteMac;
                this.encryptCipher = serverWriteCipher;
                this.decryptCipher = clientWriteCipher;
                encryptParams      = new ParametersWithIV(server_write_key, server_write_IV);
                decryptParams      = new ParametersWithIV(client_write_key, client_write_IV);
            }
            else
            {
                this.mWriteMac     = clientWriteMac;
                this.mReadMac      = serverWriteMac;
                this.encryptCipher = clientWriteCipher;
                this.decryptCipher = serverWriteCipher;
                encryptParams      = new ParametersWithIV(client_write_key, client_write_IV);
                decryptParams      = new ParametersWithIV(server_write_key, server_write_IV);
            }

            this.encryptCipher.Init(true, encryptParams);
            this.decryptCipher.Init(false, decryptParams);
        }
Example #4
0
 public TlsNullCipher(TlsContext context)
 {
     this.context  = context;
     this.writeMac = null;
     this.readMac  = null;
 }