public HeaderBruteForcer(uint[] updateCrcs, SortedList <uint, bool> checkCrcs, Tuple <byte[], int[]>[] regionData, params byte[][] headers)
{
_updateCrcs = updateCrcs;
_checkCrcs = checkCrcs;
//DateTime dt = DateTime.Now;
_hdrs = headers.Select(a => new headerCrc()
{
Crc = Crc.Compute(a), CrcPreRegion = Crc.Compute(a, 0, 0x4e000), CrcRegion = Crc.Compute(a, 0x4e000, 0x20), CrcPostRegion = Crc.Compute(a, 0x4e020, 0x1fe0), Data = a
}).ToList();
MemorySection ms = new MemorySection(headers[0]);
_origRegion = (int)ms.ReadUInt32B(0x4e000);
_origRegionData = ms.Read(0x4e010, 0x10);
_origHeaderCrcs = _hdrs.Select(a => a.Crc).ToArray(); //original header Crcs
for (int h = _hdrs.Count - 1; h >= 1; h--)
{
if (_hdrs[h].Crc == _hdrs[h - 1].Crc)
{
_hdrs.RemoveAt(h); //remove duplicate headers
}
}
_regionData = new List <regionCrc>();
for (int h = 0; h < _hdrs.Count; h++)
{
for (int i = 0; i < regionData.Length; i++)
{
for (int r = 0; r < regionData[i].Item2.Length; r++)
{
_regionData.Add(new regionCrc()
{
Crc = 0, Header = _hdrs[h], RegionData = regionData[i].Item1, Region = (int)regionData[i].Item2[r]
});
}
}
}
//parallel precalculate the crcs for the matching
Parallel.ForEach(_regionData, rgn =>
{
MemorySection rg = new MemorySection(new byte[0x20]);
rg.WriteUInt32B(0, (uint)rgn.Region);
rg.Write(0x10, rgn.RegionData);
rgn.Crc = ~Crc.Combine(Crc.Combine(~rgn.Header.CrcPreRegion, ~Crc.Compute(rg.Data), 0x20), ~rgn.Header.CrcPostRegion, 0x1fe0);
});
//Trace.WriteLine(string.Format("Crc Headers: {0} - Took: {1}", _regionData.Count.ToString(), (DateTime.Now - dt).TotalMilliseconds.ToString()));
}
public uint FullCrc(bool patched)
{
if (_crcs.Count == 0)
{
return(0);
}
uint crc = (patched && _crcs[0].PatchCrc != 0) ? _crcs[0].PatchCrc : _crcs[0].Value;
for (int i = 1; i < _crcs.Count; i++)
{
crc = ~Crc.Combine(~crc, (patched && _crcs[i].PatchCrc != 0) ? ~_crcs[i].PatchCrc : ~_crcs[i].Value, _crcs[i].Length);
}
return(crc);
}
public BruteForceCrcResult Match(CrcItem[] crcs)
{
//reduce crcs to 3 - header, update, postUpdate
_origHeaderCrc = crcs[0].Value;
_origUpdateCrc = crcs[1].Value;
long updateSize = (crcs.Length > 2 ? crcs[2].Offset - crcs[1].Offset : 0);
uint postUpdateCrc = (crcs.Length > 2 ? crcs[2].Value : 0);
long postUpdateSize = (crcs.Length > 2 ? crcs[2].Length : 0);
for (int x = 3; x < crcs.Length; x++)
{
postUpdateCrc = ~Crc.Combine(~postUpdateCrc, ~crcs[x].Value, crcs[x].Length);
postUpdateSize += crcs[x].Length;
}
//DateTime dt = DateTime.Now;
//quick test without region brute force (which can take a while)
headerCrc headerMatch = null;
regionCrc regionMatch = null;
uint matchCrc = 0;
uint matchUpdateCrc = 0;
uint u = _updateCrcs.AsParallel().FirstOrDefault(uCrc =>
{
headerCrc m = _hdrs.AsParallel().FirstOrDefault(hdr =>
{
uint crc = ~Crc.Combine(Crc.Combine(~hdr.Crc, ~uCrc, updateSize), ~postUpdateCrc, postUpdateSize);
if (_checkCrcs.ContainsKey(crc))
{
matchCrc = crc;
headerMatch = hdr;
matchUpdateCrc = uCrc;
}
return(matchCrc != 0);
});
return(matchCrc != 0);
});
//Trace.WriteLine(string.Format("Crc Update Combos: {0} - Took: {1}", _updateCrcs.Length.ToString(), (DateTime.Now - dt).TotalMilliseconds.ToString()));
if (headerMatch == null)
{
//dt = DateTime.Now;
//region brute force tests - FirstOrDefault is used and the results are discarded as nesting them causes threading issues
uint u2 = _updateCrcs.AsParallel().FirstOrDefault(uCrc =>
{
//combine the update crc with the post update crc
uint updDataCrc = ~Crc.Combine(~uCrc, ~postUpdateCrc, postUpdateSize);
long updDataSize = updateSize + postUpdateSize;
//compare the header/region with the update and post update combines crc
regionCrc m = _regionData.AsParallel().FirstOrDefault(rgn =>
{
uint crc = ~Crc.Combine(~rgn.Crc, ~updDataCrc, updDataSize);
if (_checkCrcs.ContainsKey(crc))
{
matchCrc = crc;
regionMatch = rgn;
matchUpdateCrc = uCrc;
}
return(matchCrc != 0);
});
return(matchCrc != 0);
});
//Trace.WriteLine(string.Format("Crc Header / Update Combos: {0} - Took: {1}", (_updateCrcs.Length * _regionData.Count).ToString(), (DateTime.Now - dt).TotalMilliseconds.ToString()));
}
return(results(headerMatch, regionMatch, matchUpdateCrc, matchCrc, matchCrc == 0 ? false : _checkCrcs[matchCrc]));
}
