ICSharpCode.SharpZipLib.Zip.ZipOutputStream.AddExtraDataAES C# (CSharp) Méthode

        private static void AddExtraDataAES(ZipEntry entry, ZipExtraData extraData)
        {
            // Vendor Version: AE-1 IS 1. AE-2 is 2. With AE-2 no CRC is required and 0 is stored.
            const int VENDOR_VERSION = 2;
            // Vendor ID is the two ASCII characters "AE".
            const int VENDOR_ID = 0x4541; //not 6965;
            extraData.StartNewEntry();
            // Pack AES extra data field see http://www.winzip.com/aes_info.htm
            //extraData.AddLeShort(7);							// Data size (currently 7)
            extraData.AddLeShort(VENDOR_VERSION);               // 2 = AE-2
            extraData.AddLeShort(VENDOR_ID);                    // "AE"
            extraData.AddData(entry.AESEncryptionStrength);     //  1 = 128, 2 = 192, 3 = 256
            extraData.AddLeShort((int)entry.CompressionMethod); // The actual compression method used to compress the file
            extraData.AddNewEntry(0x9901);
        }

        public override void Finish()
        {
            if (this.entries == null)
            {
                return;
            }
            if (this.curEntry != null)
            {
                this.CloseEntry();
            }
            long noOfEntries = (long)this.entries.Count;
            long num         = 0L;

            foreach (ZipEntry zipEntry in this.entries)
            {
                this.WriteLeInt(33639248);
                this.WriteLeShort(51);
                this.WriteLeShort(zipEntry.Version);
                this.WriteLeShort(zipEntry.Flags);
                this.WriteLeShort((int)((short)zipEntry.CompressionMethodForHeader));
                this.WriteLeInt((int)zipEntry.DosTime);
                this.WriteLeInt((int)zipEntry.Crc);
                if (zipEntry.IsZip64Forced() || zipEntry.CompressedSize >= (long)((ulong)-1))
                {
                    this.WriteLeInt(-1);
                }
                else
                {
                    this.WriteLeInt((int)zipEntry.CompressedSize);
                }
                if (zipEntry.IsZip64Forced() || zipEntry.Size >= (long)((ulong)-1))
                {
                    this.WriteLeInt(-1);
                }
                else
                {
                    this.WriteLeInt((int)zipEntry.Size);
                }
                byte[] array = ZipConstants.ConvertToArray(zipEntry.Flags, zipEntry.Name);
                if (array.Length > 65535)
                {
                    throw new ZipException("Name too long.");
                }
                ZipExtraData zipExtraData = new ZipExtraData(zipEntry.ExtraData);
                if (zipEntry.CentralHeaderRequiresZip64)
                {
                    zipExtraData.StartNewEntry();
                    if (zipEntry.IsZip64Forced() || zipEntry.Size >= (long)((ulong)-1))
                    {
                        zipExtraData.AddLeLong(zipEntry.Size);
                    }
                    if (zipEntry.IsZip64Forced() || zipEntry.CompressedSize >= (long)((ulong)-1))
                    {
                        zipExtraData.AddLeLong(zipEntry.CompressedSize);
                    }
                    if (zipEntry.Offset >= (long)((ulong)-1))
                    {
                        zipExtraData.AddLeLong(zipEntry.Offset);
                    }
                    zipExtraData.AddNewEntry(1);
                }
                else
                {
                    zipExtraData.Delete(1);
                }
                if (zipEntry.AESKeySize > 0)
                {
                    ZipOutputStream.AddExtraDataAES(zipEntry, zipExtraData);
                }
                byte[] entryData = zipExtraData.GetEntryData();
                byte[] array2    = (zipEntry.Comment == null) ? new byte[0] : ZipConstants.ConvertToArray(zipEntry.Flags, zipEntry.Comment);
                if (array2.Length > 65535)
                {
                    throw new ZipException("Comment too long.");
                }
                this.WriteLeShort(array.Length);
                this.WriteLeShort(entryData.Length);
                this.WriteLeShort(array2.Length);
                this.WriteLeShort(0);
                this.WriteLeShort(0);
                if (zipEntry.ExternalFileAttributes != -1)
                {
                    this.WriteLeInt(zipEntry.ExternalFileAttributes);
                }
                else if (zipEntry.IsDirectory)
                {
                    this.WriteLeInt(16);
                }
                else
                {
                    this.WriteLeInt(0);
                }
                if (zipEntry.Offset >= (long)((ulong)-1))
                {
                    this.WriteLeInt(-1);
                }
                else
                {
                    this.WriteLeInt((int)zipEntry.Offset);
                }
                if (array.Length > 0)
                {
                    this.baseOutputStream_.Write(array, 0, array.Length);
                }
                if (entryData.Length > 0)
                {
                    this.baseOutputStream_.Write(entryData, 0, entryData.Length);
                }
                if (array2.Length > 0)
                {
                    this.baseOutputStream_.Write(array2, 0, array2.Length);
                }
                num += (long)(46 + array.Length + entryData.Length + array2.Length);
            }
            using (ZipHelperStream zipHelperStream = new ZipHelperStream(this.baseOutputStream_))
            {
                zipHelperStream.WriteEndOfCentralDirectory(noOfEntries, num, this.offset, this.zipComment);
            }
            this.entries = null;
        }