public override RelocationResults Relocate(Address addrLoad)
{
ImageMap imageMap = imgLoadedMap;
ImageReader rdr = new LeImageReader(exe.RawImage, (uint) exe.e_lfaRelocations);
var relocations = new RelocationDictionary();
int i = exe.e_cRelocations;
while (i != 0)
{
uint offset = rdr.ReadLeUInt16();
ushort segOffset = rdr.ReadLeUInt16();
offset += segOffset * 0x0010u;
ushort seg = (ushort) (imgLoaded.ReadLeUInt16(offset) + addrLoad.Selector);
imgLoaded.WriteLeUInt16(offset, seg);
relocations.AddSegmentReference(offset, seg);
imageMap.AddSegment(Address.SegPtr(seg, 0), seg.ToString("X4"), AccessMode.ReadWriteExecute);
--i;
}
// Found the start address.
Address addrStart = Address.SegPtr((ushort)(exe.e_cs + addrLoad.Selector), exe.e_ip);
imageMap.AddSegment(Address.SegPtr(addrStart.Selector, 0), addrStart.Selector.ToString("X4"), AccessMode.ReadWriteExecute);
return new RelocationResults(
new List<EntryPoint> { new EntryPoint(addrStart, arch.CreateProcessorState()) },
relocations);
}
public ExePackLoader(IServiceProvider services, string filename, byte[] imgRaw)
: base(services, filename, imgRaw)
{
arch = new IntelArchitecture(ProcessorMode.Real);
platform = new MsdosPlatform(Services, arch);
var exe = new ExeImageLoader(services, filename, imgRaw);
this.exeHdrSize = (uint)(exe.e_cparHeader * 0x10U);
this.hdrOffset = (uint)(exe.e_cparHeader + exe.e_cs) * 0x10U;
ImageReader rdr = new LeImageReader(RawImage, hdrOffset);
this.ip = rdr.ReadLeUInt16();
this.cs = rdr.ReadLeUInt16();
rdr.ReadLeUInt16();
this.cbExepackHeader = rdr.ReadLeUInt16();
this.sp = rdr.ReadLeUInt16();
this.ss = rdr.ReadLeUInt16();
this.cpUncompressed = rdr.ReadLeUInt16();
int offset = ExePackHeaderOffset(exe);
if (LoadedImage.CompareArrays(imgRaw, offset, signature, signature.Length))
{
relocationsOffset = 0x012D;
}
else if (LoadedImage.CompareArrays(imgRaw, offset, signature2, signature2.Length))
{
relocationsOffset = 0x0125;
}
else
throw new ApplicationException("Not a recognized EXEPACK image.");
}
private FileHeader LoadHeader()
{
var rdr = new LeImageReader(RawImage, 0);
var magic = rdr.ReadLeUInt16();
switch (magic)
{
case 0x014C: arch = new IntelArchitecture(ProcessorMode.Protected32); break;
default: throw new NotSupportedException();
}
return new FileHeader
{
f_magic = magic,
f_nscns = rdr.ReadUInt16(),
f_timdat = rdr.ReadUInt32(),
f_symptr = rdr.ReadUInt32(),
f_nsyms = rdr.ReadUInt32(),
f_opthdr = rdr.ReadUInt16(),
f_flags = rdr.ReadUInt16(),
};
}
public LoadedImage Unpack(byte [] abC, Address addrLoad)
{
// Extract the LZ stuff.
ImageReader rdr = new LeImageReader(abC, (uint) lzHdrOffset);
lzIp = rdr.ReadLeUInt16();
lzCs = rdr.ReadLeUInt16();
ushort lzSp = rdr.ReadLeUInt16();
ushort lzSs = rdr.ReadLeUInt16();
ushort lzcpCompressed = rdr.ReadLeUInt16();
ushort lzcpDecompressed = rdr.ReadLeUInt16();
// Find the start of the compressed stream.
int ifile = lzHdrOffset - (lzcpCompressed << 4);
// Allocate space for the decompressed goo.
int cbUncompressed = ((int) lzcpDecompressed + lzcpDecompressed) << 4;
byte [] abU = new byte[cbUncompressed];
// Decompress this sorry mess.
int len;
int span;
int p = 0;
BitStream bits = new BitStream(abC, ifile);
for (;;)
{
if (bits.GetBit() != 0)
{
// 1....
abU[p++] = bits.GetByte();
continue;
}
if (bits.GetBit() == 0)
{
// 00.....
len = bits.GetBit() << 1;
len |= bits.GetBit();
len += 2;
span = bits.GetByte() | ~0xFF;
}
else
{
// 01.....
span = bits.GetByte();
len = bits.GetByte();;
span |= ((len & ~0x07)<<5) | ~0x1FFF;
len = (len & 0x07) + 2;
if (len == 2)
{
len = bits.GetByte();
if (len == 0)
break; // end mark of compressed load module
if (len == 1)
continue; // segment change
else
++len;
}
}
for( ;len > 0; --len, ++p)
{
abU[p] = abU[p+span];
}
}
// Create a new image based on the uncompressed data.
this.imgLoaded = new LoadedImage(addrLoad, abU);
this.imageMap = imgLoaded.CreateImageMap();
return imgLoaded;
}
public void ReadCommonExeFields()
{
ImageReader rdr = new LeImageReader(RawImage, 0);
e_magic = rdr.ReadLeUInt16();
e_cbLastPage = rdr.ReadLeUInt16();
e_cpImage = rdr.ReadLeUInt16();
this.e_cRelocations = rdr.ReadLeUInt16();
e_cparHeader = rdr.ReadLeUInt16();
e_minalloc = rdr.ReadLeUInt16();
e_maxalloc = rdr.ReadLeUInt16();
e_ss = rdr.ReadLeUInt16();
e_sp = rdr.ReadLeUInt16();
e_csum = rdr.ReadLeUInt16();
e_ip = rdr.ReadLeUInt16();
e_cs = rdr.ReadLeUInt16();
e_lfaRelocations = rdr.ReadLeUInt16();
e_ovno = rdr.ReadLeUInt16();
e_res = new ushort[4];
for (int i = 0; i != 4; ++i)
{
e_res[i] = rdr.ReadLeUInt16();
}
e_oemid = rdr.ReadLeUInt16();
e_oeminfo = rdr.ReadLeUInt16();
e_res2 = new ushort[10];
for (int i = 0; i != 10; ++i)
{
e_res2[i] = rdr.ReadLeUInt16();
}
e_lfanew = rdr.ReadLeUInt32();
}
public override RelocationResults Relocate(Address addrLoad)
{
ImageReader rdr = new LeImageReader(RawImage, hdrOffset + relocationsOffset);
ushort segCode = (ushort)(addrLoad.Selector + (ExeImageLoader.CbPsp >> 4));
ushort dx = 0;
for (; ; )
{
int cx = rdr.ReadLeUInt16();
if (cx != 0)
{
uint relocBase = ExeImageLoader.CbPsp + dx * 0x10u;
do
{
ushort relocOff = rdr.ReadLeUInt16();
ushort seg = imgU.FixupLeUInt16(relocBase + relocOff, segCode);
imageMap.AddSegment(Address.SegPtr(seg, 0), seg.ToString("X4"), AccessMode.ReadWriteExecute);
} while (--cx != 0);
}
if (dx == 0xF000)
break;
dx += (ushort)0x1000U;
}
this.cs += segCode;
imageMap.AddSegment(Address.SegPtr(cs, 0), cs.ToString("X4"), AccessMode.ReadWriteExecute);
this.ss += segCode;
var state = arch.CreateProcessorState();
state.SetRegister(Registers.ds, Constant.Word16(addrLoad.Selector));
state.SetRegister(Registers.es, Constant.Word16(addrLoad.Selector));
state.SetRegister(Registers.cs, Constant.Word16(cs));
state.SetRegister(Registers.ss, Constant.Word16(ss));
state.SetRegister(Registers.bx, Constant.Word16(0));
var entryPoints = new List<EntryPoint>
{
new EntryPoint(Address.SegPtr(cs, ip), state)
};
return new RelocationResults(entryPoints, new RelocationDictionary());
}