/// <summary>
        /// Initializes encryption keys based on given <paramref name="password"/>.
        /// </summary>
        /// <param name="password">The password.</param>
        protected void InitializePassword(string password)
        {
            PkblubbClassicManaged pkManaged = new PkblubbClassicManaged();

            byte[] key = PkblubbClassic.GenerateKeys(BlubbZipConstants.ConvertToArray(password));
            cryptoTransform_ = pkManaged.CreateEncryptor(key, null);
        }
Esempio n. 2
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        /// <summary>
        /// Perform the initial read on an entry which may include
        /// reading encryption headers and setting up inflation.
        /// </summary>
        /// <param name="destination">The destination to fill with data read.</param>
        /// <param name="offset">The offset to start reading at.</param>
        /// <param name="count">The maximum number of bytes to read.</param>
        /// <returns>The actual number of bytes read.</returns>
        int InitialRead(byte[] destination, int offset, int count)
        {
            if (!CanDecompressEntry)
            {
                throw new BlubbZipException("Library cannot extract this entry. Version required is (" + entry.Version.ToString() + ")");
            }

            // Handle encryption if required.
            if (entry.IsCrypted)
            {
                if (password == null)
                {
                    throw new BlubbZipException("No password set.");
                }

                // Generate and set crypto transform...
                PkblubbClassicManaged managed = new PkblubbClassicManaged();
                byte[] key = PkblubbClassic.GenerateKeys(BlubbZipConstants.ConvertToArray(password));

                inputBuffer.CryptoTransform = managed.CreateDecryptor(key, null);

                byte[] cryptbuffer = new byte[BlubbZipConstants.CryptoHeaderSize];
                inputBuffer.ReadClearTextBuffer(cryptbuffer, 0, BlubbZipConstants.CryptoHeaderSize);

                if (cryptbuffer[BlubbZipConstants.CryptoHeaderSize - 1] != entry.CryptoCheckValue)
                {
                    throw new BlubbZipException("Invalid password");
                }

                if (csize >= BlubbZipConstants.CryptoHeaderSize)
                {
                    csize -= BlubbZipConstants.CryptoHeaderSize;
                }
                else if ((entry.Flags & (int)GeneralBitFlags.Descriptor) == 0)
                {
                    throw new BlubbZipException(string.Format("Entry compressed size {0} too small for encryption", csize));
                }
            }
            else
            {
                inputBuffer.CryptoTransform = null;
            }

            if ((csize > 0) || ((flags & (int)GeneralBitFlags.Descriptor) != 0))
            {
                if ((method == (int)CompressionMethod.Deflated) && (inputBuffer.Available > 0))
                {
                    inputBuffer.SetInflaterInput(inf);
                }

                internalReader = new ReadDataHandler(BodyRead);
                return(BodyRead(destination, offset, count));
            }
            else
            {
                internalReader = new ReadDataHandler(ReadingNotAvailable);
                return(0);
            }
        }