Beispiel #1
0
        public Aes128CtrExStorage(IStorage baseStorage, IStorage bucketTreeHeader, IStorage bucketTreeData, byte[] key, long counterOffset, byte[] ctrHi, bool leaveOpen)
            : base(baseStorage, key, counterOffset, ctrHi, leaveOpen)
        {
            BucketTree = new BucketTree <AesSubsectionEntry>(bucketTreeHeader, bucketTreeData);

            SubsectionEntries = BucketTree.GetEntryList();
            SubsectionOffsets = SubsectionEntries.Select(x => x.Offset).ToList();
        }
Beispiel #2
0
        public BktrCryptoStream(Stream baseStream, byte[] key, long offset, long length, long counterOffset, byte[] ctrHi, BktrSuperblock bktr)
            : base(baseStream, key, offset, length, counterOffset, ctrHi)
        {
            BktrHeader header = bktr.SubsectionHeader;

            byte[] subsectionBytes;
            using (var streamDec = new RandomAccessSectorStream(new Aes128CtrStream(baseStream, key, offset, length, counterOffset, ctrHi)))
            {
                streamDec.Position = header.Offset;
                subsectionBytes    = new byte[header.Size];
                streamDec.Read(subsectionBytes, 0, subsectionBytes.Length);
            }

            using (var reader = new BinaryReader(new MemoryStream(subsectionBytes)))
            {
                SubsectionBlock = new SubsectionBlock(reader);
            }

            foreach (SubsectionBucket bucket in SubsectionBlock.Buckets)
            {
                SubsectionEntries.AddRange(bucket.Entries);
            }

            // Add a subsection for the BKTR headers to make things easier
            var headerSubsection = new SubsectionEntry
            {
                Offset    = bktr.RelocationHeader.Offset,
                Counter   = (uint)(ctrHi[4] << 24 | ctrHi[5] << 16 | ctrHi[6] << 8 | ctrHi[7]),
                OffsetEnd = long.MaxValue
            };

            SubsectionEntries.Add(headerSubsection);

            for (int i = 0; i < SubsectionEntries.Count - 1; i++)
            {
                SubsectionEntries[i].Next      = SubsectionEntries[i + 1];
                SubsectionEntries[i].OffsetEnd = SubsectionEntries[i + 1].Offset;
            }

            SubsectionOffsets = SubsectionEntries.Select(x => x.Offset).ToList();

            CurrentEntry = GetSubsectionEntry(0);
            UpdateCounterSubsection(CurrentEntry.Counter);
            baseStream.Position = offset;
        }