Files
BinaryObjectScanner/BinaryObjectScanner.Builders/CFB.cs
Matt Nadareski 473cbc5694 BOS.* -> BOS.*
2023-03-07 16:59:14 -05:00

392 lines
15 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using BinaryObjectScanner.Models.CFB;
using BinaryObjectScanner.Utilities;
using static BinaryObjectScanner.Models.CFB.Constants;
namespace BinaryObjectScanner.Builders
{
public class CFB
{
#region Byte Data
/// <summary>
/// Parse a byte array into a Compound File Binary
/// </summary>
/// <param name="data">Byte array to parse</param>
/// <param name="offset">Offset into the byte array</param>
/// <returns>Filled Compound File Binary on success, null on error</returns>
public static Binary ParseBinary(byte[] data, int offset)
{
// If the data is invalid
if (data == null)
return null;
// If the offset is out of bounds
if (offset < 0 || offset >= data.Length)
return null;
// Create a memory stream and parse that
MemoryStream dataStream = new MemoryStream(data, offset, data.Length - offset);
return ParseBinary(dataStream);
}
#endregion
#region Stream Data
/// <summary>
/// Parse a Stream into a Compound File Binary
/// </summary>
/// <param name="data">Stream to parse</param>
/// <returns>Filled Compound File Binary on success, null on error</returns>
public static Binary ParseBinary(Stream data)
{
// If the data is invalid
if (data == null || data.Length == 0 || !data.CanSeek || !data.CanRead)
return null;
// If the offset is out of bounds
if (data.Position < 0 || data.Position >= data.Length)
return null;
// Cache the current offset
int initialOffset = (int)data.Position;
// Create a new binary to fill
var binary = new Binary();
#region Header
// Try to parse the file header
var fileHeader = ParseFileHeader(data);
if (fileHeader == null)
return null;
// Set the file header
binary.Header = fileHeader;
#endregion
#region DIFAT Sector Numbers
// Create a DIFAT sector table
var difatSectors = new List<SectorNumber>();
// Add the sectors from the header
difatSectors.AddRange(fileHeader.DIFAT);
// Loop through and add the DIFAT sectors
SectorNumber currentSector = (SectorNumber)fileHeader.FirstDIFATSectorLocation;
for (int i = 0; i < fileHeader.NumberOfDIFATSectors; i++)
{
// If we have a readable sector
if (currentSector <= SectorNumber.MAXREGSECT)
{
// Get the new next sector information
long sectorOffset = (long)((long)(currentSector + 1) * Math.Pow(2, fileHeader.SectorShift));
if (sectorOffset < 0 || sectorOffset >= data.Length)
return null;
// Seek to the next sector
data.Seek(sectorOffset, SeekOrigin.Begin);
// Try to parse the sectors
var sectorNumbers = ParseSectorNumbers(data, fileHeader.SectorShift);
if (sectorNumbers == null)
return null;
// Add the sector shifts
difatSectors.AddRange(sectorNumbers);
}
// Get the next sector from the DIFAT
currentSector = difatSectors[i];
}
// Assign the DIFAT sectors table
binary.DIFATSectorNumbers = difatSectors.ToArray();
#endregion
#region FAT Sector Numbers
// Create a FAT sector table
var fatSectors = new List<SectorNumber>();
// Loop through and add the FAT sectors
currentSector = binary.DIFATSectorNumbers[0];
for (int i = 0; i < fileHeader.NumberOfFATSectors; i++)
{
// If we have a readable sector
if (currentSector <= SectorNumber.MAXREGSECT)
{
// Get the new next sector information
long sectorOffset = (long)((long)(currentSector + 1) * Math.Pow(2, fileHeader.SectorShift));
if (sectorOffset < 0 || sectorOffset >= data.Length)
return null;
// Seek to the next sector
data.Seek(sectorOffset, SeekOrigin.Begin);
// Try to parse the sectors
var sectorNumbers = ParseSectorNumbers(data, fileHeader.SectorShift);
if (sectorNumbers == null)
return null;
// Add the sector shifts
fatSectors.AddRange(sectorNumbers);
}
// Get the next sector from the DIFAT
currentSector = binary.DIFATSectorNumbers[i];
}
// Assign the FAT sectors table
binary.FATSectorNumbers = fatSectors.ToArray();
#endregion
#region Mini FAT Sector Numbers
// Create a mini FAT sector table
var miniFatSectors = new List<SectorNumber>();
// Loop through and add the mini FAT sectors
currentSector = (SectorNumber)fileHeader.FirstMiniFATSectorLocation;
for (int i = 0; i < fileHeader.NumberOfMiniFATSectors; i++)
{
// If we have a readable sector
if (currentSector <= SectorNumber.MAXREGSECT)
{
// Get the new next sector information
long sectorOffset = (long)((long)(currentSector + 1) * Math.Pow(2, fileHeader.SectorShift));
if (sectorOffset < 0 || sectorOffset >= data.Length)
return null;
// Seek to the next sector
data.Seek(sectorOffset, SeekOrigin.Begin);
// Try to parse the sectors
var sectorNumbers = ParseSectorNumbers(data, fileHeader.SectorShift);
if (sectorNumbers == null)
return null;
// Add the sector shifts
miniFatSectors.AddRange(sectorNumbers);
}
// Get the next sector from the DIFAT
currentSector = binary.DIFATSectorNumbers[i];
}
// Assign the mini FAT sectors table
binary.MiniFATSectorNumbers = miniFatSectors.ToArray();
#endregion
#region Directory Entries
// Get the offset of the first directory sector
long firstDirectoryOffset = (long)(fileHeader.FirstDirectorySectorLocation * Math.Pow(2, fileHeader.SectorShift));
if (firstDirectoryOffset < 0 || firstDirectoryOffset >= data.Length)
return null;
// Seek to the first directory sector
data.Seek(firstDirectoryOffset, SeekOrigin.Begin);
// Create a directory sector table
var directorySectors = new List<DirectoryEntry>();
// Get the number of directory sectors
uint directorySectorCount = 0;
switch (fileHeader.MajorVersion)
{
case 3:
directorySectorCount = int.MaxValue;
break;
case 4:
directorySectorCount = fileHeader.NumberOfDirectorySectors;
break;
}
// Loop through and add the directory sectors
currentSector = (SectorNumber)fileHeader.FirstDirectorySectorLocation;
for (int i = 0; i < directorySectorCount; i++)
{
// If we have an end of chain
if (currentSector == SectorNumber.ENDOFCHAIN)
break;
// If we have a readable sector
if (currentSector <= SectorNumber.MAXREGSECT)
{
// Get the new next sector information
long sectorOffset = (long)((long)(currentSector + 1) * Math.Pow(2, fileHeader.SectorShift));
if (sectorOffset < 0 || sectorOffset >= data.Length)
return null;
// Seek to the next sector
data.Seek(sectorOffset, SeekOrigin.Begin);
// Try to parse the sectors
var directoryEntries = ParseDirectoryEntries(data, fileHeader.SectorShift, fileHeader.MajorVersion);
if (directoryEntries == null)
return null;
// Add the sector shifts
directorySectors.AddRange(directoryEntries);
}
// Get the next sector from the DIFAT
currentSector = binary.DIFATSectorNumbers[i];
}
// Assign the Directory sectors table
binary.DirectoryEntries = directorySectors.ToArray();
#endregion
return binary;
}
/// <summary>
/// Parse a Stream into a file header
/// </summary>
/// <param name="data">Stream to parse</param>
/// <returns>Filled file header on success, null on error</returns>
private static FileHeader ParseFileHeader(Stream data)
{
// TODO: Use marshalling here instead of building
FileHeader header = new FileHeader();
header.Signature = data.ReadUInt64();
if (header.Signature != SignatureUInt64)
return null;
header.CLSID = data.ReadGuid();
header.MinorVersion = data.ReadUInt16();
header.MajorVersion = data.ReadUInt16();
header.ByteOrder = data.ReadUInt16();
if (header.ByteOrder != 0xFFFE)
return null;
header.SectorShift = data.ReadUInt16();
if (header.MajorVersion == 3 && header.SectorShift != 0x0009)
return null;
else if (header.MajorVersion == 4 && header.SectorShift != 0x000C)
return null;
header.MiniSectorShift = data.ReadUInt16();
header.Reserved = data.ReadBytes(6);
header.NumberOfDirectorySectors = data.ReadUInt32();
if (header.MajorVersion == 3 && header.NumberOfDirectorySectors != 0)
return null;
header.NumberOfFATSectors = data.ReadUInt32();
header.FirstDirectorySectorLocation = data.ReadUInt32();
header.TransactionSignatureNumber = data.ReadUInt32();
header.MiniStreamCutoffSize = data.ReadUInt32();
if (header.MiniStreamCutoffSize != 0x00001000)
return null;
header.FirstMiniFATSectorLocation = data.ReadUInt32();
header.NumberOfMiniFATSectors = data.ReadUInt32();
header.FirstDIFATSectorLocation = data.ReadUInt32();
header.NumberOfDIFATSectors = data.ReadUInt32();
header.DIFAT = new SectorNumber[109];
for (int i = 0; i < header.DIFAT.Length; i++)
{
header.DIFAT[i] = (SectorNumber)data.ReadUInt32();
}
// Skip rest of sector for version 4
if (header.MajorVersion == 4)
_ = data.ReadBytes(3584);
return header;
}
/// <summary>
/// Parse a Stream into a sector full of sector numbers
/// </summary>
/// <param name="data">Stream to parse</param>
/// <param name="sectorShift">Sector shift from the header</param>
/// <returns>Filled sector full of sector numbers on success, null on error</returns>
private static SectorNumber[] ParseSectorNumbers(Stream data, ushort sectorShift)
{
// TODO: Use marshalling here instead of building
int sectorCount = (int)(Math.Pow(2, sectorShift) / sizeof(uint));
SectorNumber[] sectorNumbers = new SectorNumber[sectorCount];
for (int i = 0; i < sectorNumbers.Length; i++)
{
sectorNumbers[i] = (SectorNumber)data.ReadUInt32();
}
return sectorNumbers;
}
/// <summary>
/// Parse a Stream into a sector full of directory entries
/// </summary>
/// <param name="data">Stream to parse</param>
/// <param name="sectorShift">Sector shift from the header</param>
/// <param name="majorVersion">Major version from the header</param>
/// <returns>Filled sector full of directory entries on success, null on error</returns>
private static DirectoryEntry[] ParseDirectoryEntries(Stream data, ushort sectorShift, ushort majorVersion)
{
// TODO: Use marshalling here instead of building
const int directoryEntrySize = 64 + 2 + 1 + 1 + 4 + 4 + 4 + 16 + 4 + 8 + 8 + 4 + 8;
int sectorCount = (int)(Math.Pow(2, sectorShift) / directoryEntrySize);
DirectoryEntry[] directoryEntries = new DirectoryEntry[sectorCount];
for (int i = 0; i < directoryEntries.Length; i++)
{
var directoryEntry = ParseDirectoryEntry(data, majorVersion);
if (directoryEntry == null)
return null;
directoryEntries[i] = directoryEntry;
}
return directoryEntries;
}
/// <summary>
/// Parse a Stream into a directory entry
/// </summary>
/// <param name="data">Stream to parse</param>
/// <param name="majorVersion">Major version from the header</param>
/// <returns>Filled directory entry on success, null on error</returns>
private static DirectoryEntry ParseDirectoryEntry(Stream data, ushort majorVersion)
{
// TODO: Use marshalling here instead of building
DirectoryEntry directoryEntry = new DirectoryEntry();
byte[] name = data.ReadBytes(64);
directoryEntry.Name = Encoding.Unicode.GetString(name).TrimEnd('\0');
directoryEntry.NameLength = data.ReadUInt16();
directoryEntry.ObjectType = (ObjectType)data.ReadByteValue();
directoryEntry.ColorFlag = (ColorFlag)data.ReadByteValue();
directoryEntry.LeftSiblingID = (StreamID)data.ReadUInt32();
directoryEntry.RightSiblingID = (StreamID)data.ReadUInt32();
directoryEntry.ChildID = (StreamID)data.ReadUInt32();
directoryEntry.CLSID = data.ReadGuid();
directoryEntry.StateBits = data.ReadUInt32();
directoryEntry.CreationTime = data.ReadUInt64();
directoryEntry.ModifiedTime = data.ReadUInt64();
directoryEntry.StartingSectorLocation = data.ReadUInt32();
directoryEntry.StreamSize = data.ReadUInt64();
if (majorVersion == 3)
directoryEntry.StreamSize &= 0x0000FFFF;
return directoryEntry;
}
#endregion
}
}