private InlineHook(QHackContext ctx, AssemblyCode code, HookParameters parameters)
{
Context = ctx;
Code = code.Copy();
MemoryAllocation = new MemoryAllocation(ctx);
Parameters = parameters;
byte[] headInstBytes = GetHeadBytes(Context.DataAccess.ReadBytes(Parameters.TargetAddress, 32));
nuint allocAddr = MemoryAllocation.AllocationBase;
nuint safeFreeFlagAddr = allocAddr + (uint)HookInfo.Offset_SafeFreeFlag;
nuint onceFlagAddr = allocAddr + (uint)HookInfo.Offset_OnceFlag;
nuint codeAddr = allocAddr + (uint)HookInfo.HeaderSize;
nuint retAddr = Parameters.TargetAddress + (uint)headInstBytes.Length;
HookInfo info = new(allocAddr, headInstBytes);
Assembler assembler = new();
assembler.Emit(DataHelper.GetBytes(info)); //emit the header before runnable code
assembler.Emit((Instruction)$"mov dword ptr [{safeFreeFlagAddr}],1");
assembler.Emit(Parameters.IsOnce ? GetOnceCheckedCode(Code, onceFlagAddr) : Code); //once or not
if (Parameters.Original)
{
assembler.Emit(headInstBytes); //emit the raw code replaced by hook jmp
}
assembler.Emit((Instruction)$"mov dword ptr [{safeFreeFlagAddr}],0");
assembler.Emit((Instruction)$"jmp {retAddr}");
Context.DataAccess.WriteBytes(allocAddr, assembler.GetByteCode(allocAddr));
JmpHeadBytes = new byte[headInstBytes.Length];
Array.Fill <byte>(JmpHeadBytes, 0x90);
Assembler.Assemble($"jmp {codeAddr}", Parameters.TargetAddress).CopyTo(JmpHeadBytes, 0);
}
public static InlineHook Hook(QHackContext ctx, AssemblyCode code, HookParameters parameters)
{
var hook = new InlineHook(ctx, code, parameters);
hook.Attach();
return(hook);
}
