/// <summary>
/// Create a new AaruFormat from an input stream
/// </summary>
/// <param name="aarustream">Stream representing the AaruFormat file</param>
public static AaruFormat Create(Stream aarustream)
{
try
{
// Validate that this is actually a valid AaruFormat (by magic string alone)
bool validated = ValidateHeader(aarustream);
aarustream.SeekIfPossible(); // Seek back to start
if (!validated)
{
return(null);
}
// Read and retrun the current AaruFormat
AaruFormat generated = Deserialize(aarustream);
if (generated != null)
{
generated.Type = FileType.AaruFormat;
}
return(generated);
}
catch
{
return(null);
}
}
/// <summary>
/// Read a stream as an AaruFormat
/// </summary>
/// <param name="stream">AaruFormat file as a stream</param>
/// <returns>Populated AaruFormat file, null on failure</returns>
public static AaruFormat Deserialize(Stream stream)
{
try
{
AaruFormat aif = new AaruFormat();
using (BinaryReader br = new BinaryReader(stream, Encoding.Default, true))
{
aif.Identifier = br.ReadUInt64();
aif.Application = Encoding.Unicode.GetString(br.ReadBytes(64), 0, 64);
aif.ImageMajorVersion = br.ReadByte();
aif.ImageMinorVersion = br.ReadByte();
aif.ApplicationMajorVersion = br.ReadByte();
aif.ApplicationMinorVersion = br.ReadByte();
aif.MediaType = (AaruMediaType)br.ReadUInt32();
aif.IndexOffset = br.ReadUInt64();
aif.CreationTime = br.ReadInt64();
aif.LastWrittenTime = br.ReadInt64();
// If the offset is bigger than the stream, we can't read it
if (aif.IndexOffset > (ulong)stream.Length)
{
return(null);
}
// Otherwise, we read in the index header
stream.Seek((long)aif.IndexOffset, SeekOrigin.Begin);
aif.IndexHeader = IndexHeader.Deserialize(stream);
if (aif.IndexHeader.entries == 0)
{
return(null);
}
// Get the list of entries
aif.IndexEntries = new IndexEntry[aif.IndexHeader.entries];
for (ushort index = 0; index < aif.IndexHeader.entries; index++)
{
aif.IndexEntries[index] = IndexEntry.Deserialize(stream);
switch (aif.IndexEntries[index].blockType)
{
// We don't do anything with these block types currently
case AaruBlockType.DataBlock:
case AaruBlockType.DeDuplicationTable:
case AaruBlockType.Index:
case AaruBlockType.Index2:
case AaruBlockType.GeometryBlock:
case AaruBlockType.MetadataBlock:
case AaruBlockType.TracksBlock:
case AaruBlockType.CicmBlock:
case AaruBlockType.DataPositionMeasurementBlock:
case AaruBlockType.SnapshotBlock:
case AaruBlockType.ParentBlock:
case AaruBlockType.DumpHardwareBlock:
case AaruBlockType.TapeFileBlock:
case AaruBlockType.TapePartitionBlock:
case AaruBlockType.CompactDiscIndexesBlock:
// No-op
break;
// Read in all available hashes
case AaruBlockType.ChecksumBlock:
// If the offset is bigger than the stream, we can't read it
if (aif.IndexEntries[index].offset > (ulong)stream.Length)
{
return(null);
}
// Otherwise, we read in the block
stream.Seek((long)aif.IndexEntries[index].offset, SeekOrigin.Begin);
ChecksumHeader checksumHeader = ChecksumHeader.Deserialize(stream);
if (checksumHeader.entries == 0)
{
return(null);
}
// Read through each and pick out the ones we care about
for (byte entry = 0; entry < checksumHeader.entries; entry++)
{
ChecksumEntry checksumEntry = ChecksumEntry.Deserialize(stream);
if (checksumEntry == null)
{
continue;
}
switch (checksumEntry.type)
{
case AaruChecksumAlgorithm.Invalid:
break;
case AaruChecksumAlgorithm.Md5:
aif.MD5 = checksumEntry.checksum;
break;
case AaruChecksumAlgorithm.Sha1:
aif.SHA1 = checksumEntry.checksum;
break;
case AaruChecksumAlgorithm.Sha256:
aif.SHA256 = checksumEntry.checksum;
break;
case AaruChecksumAlgorithm.SpamSum:
aif.SpamSum = checksumEntry.checksum;
break;
}
}
// Once we got hashes, we return early
return(aif);
}
}
}
return(aif);
}
catch
{
// We don't care what the error was at this point
return(null);
}
}
