ToxicMushroom/Dalamud
1
0
Fork 0
mirror of https://github.com/goatcorp/Dalamud.git synced 2025-12-15 05:04:15 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

Fix import hook

Browse source
This commit is contained in:
Soreepeong 2023-03-10 22:28:08 +09:00
parent c0954035da
commit 9ee8ad67b4
3 changed files with 174 additions and 26 deletions
Download patch file Download diff file Expand all files Collapse all files

88
Dalamud/Hooking/Internal/FunctionPointerVariableHook.cs
View file

@ -1,4 +1,5 @@
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Reflection;
using System.Runtime.InteropServices;
@ -11,13 +12,20 @@ namespace Dalamud.Hooking.Internal;
/// Manages a hook with MinHook.
/// </summary>
/// <typeparam name="T">Delegate type to represents a function prototype. This must be the same prototype as original function do.</typeparam>
internal class FunctionPointerVariableHook<T> : Hook<T> where T : Delegate
internal unsafe class FunctionPointerVariableHook<T> : Hook<T>
where T : Delegate
{
private readonly nint pfnDetour;
// Keep it referenced so that pfnDetour doesn't become invalidated.
// ReSharper disable once NotAccessedField.Local
private readonly T detourDelegate;
private nint pfnOriginal;
private T? originalDelegate;
private readonly byte* pfnThunk;
private readonly nint* ppfnThunkJumpTarget;
private readonly nint pfnOriginal;
private readonly T originalDelegate;
private bool enabled = false;
@ -40,11 +48,45 @@ internal class FunctionPointerVariableHook<T> : Hook<T> where T : Delegate
}
if (!HookManager.MultiHookTracker.TryGetValue(this.Address, out var indexList))
indexList = HookManager.MultiHookTracker[this.Address] = new();
{
indexList = HookManager.MultiHookTracker[this.Address] = new List<IDalamudHook>();
}
this.detourDelegate = detour;
this.pfnDetour = Marshal.GetFunctionPointerForDelegate(detour);
this.pfnThunk = (byte*)NativeFunctions.HeapAlloc(HookManager.NoFreeExecutableHeap, 0, 12);
if (this.pfnThunk == null)
{
throw new OutOfMemoryException("Failed to allocate memory for import hooks.");
}
// movabs rax, imm
this.pfnThunk[0] = 0x48;
this.pfnThunk[1] = 0xB8;
this.ppfnThunkJumpTarget = (nint*)&this.pfnThunk[2];
// jmp rax
this.pfnThunk[10] = 0xFF;
this.pfnThunk[11] = 0xE0;
if (!NativeFunctions.VirtualProtect(
this.Address,
(UIntPtr)Marshal.SizeOf<IntPtr>(),
MemoryProtection.ExecuteReadWrite,
out var oldProtect))
{
throw new Win32Exception(Marshal.GetLastWin32Error());
}
this.pfnOriginal = Marshal.ReadIntPtr(this.Address);
this.originalDelegate = Marshal.GetDelegateForFunctionPointer<T>(this.pfnOriginal);
*this.ppfnThunkJumpTarget = this.pfnOriginal;
Marshal.WriteIntPtr(this.Address, this.pfnDetour);
// This really should not fail, but then even if it does, whatever.
NativeFunctions.VirtualProtect(this.Address, (UIntPtr)Marshal.SizeOf<IntPtr>(), oldProtect, out _);
// Add afterwards, so the hookIdent starts at 0.
indexList.Add(this);
@ -79,7 +121,9 @@ internal class FunctionPointerVariableHook<T> : Hook<T> where T : Delegate
public override void Dispose()
{
if (this.IsDisposed)
{
return;
}
this.Disable();
@ -94,19 +138,15 @@ internal class FunctionPointerVariableHook<T> : Hook<T> where T : Delegate
{
this.CheckDisposed();
if (!this.enabled)
if (this.enabled)
{
lock (HookManager.HookEnableSyncRoot)
{
if (!NativeFunctions.VirtualProtect(this.Address, (UIntPtr)Marshal.SizeOf<IntPtr>(), MemoryProtection.ExecuteReadWrite, out var oldProtect))
throw new Win32Exception(Marshal.GetLastWin32Error());
return;
}
this.pfnOriginal = Marshal.ReadIntPtr(this.Address);
this.originalDelegate = Marshal.GetDelegateForFunctionPointer<T>(this.pfnOriginal);
Marshal.WriteIntPtr(this.Address, this.pfnDetour);
NativeFunctions.VirtualProtect(this.Address, (UIntPtr)Marshal.SizeOf<IntPtr>(), oldProtect, out _);
}
lock (HookManager.HookEnableSyncRoot)
{
*this.ppfnThunkJumpTarget = this.pfnDetour;
this.enabled = true;
}
}
@ -115,19 +155,15 @@ internal class FunctionPointerVariableHook<T> : Hook<T> where T : Delegate
{
this.CheckDisposed();
if (this.enabled)
if (!this.enabled)
{
lock (HookManager.HookEnableSyncRoot)
{
if (!NativeFunctions.VirtualProtect(this.Address, (UIntPtr)Marshal.SizeOf<IntPtr>(), MemoryProtection.ExecuteReadWrite, out var oldProtect))
throw new Win32Exception(Marshal.GetLastWin32Error());
return;
}
if (Marshal.ReadIntPtr(this.Address) != this.pfnOriginal)
Environment.FailFast("Cannot disable this hook in a sane manner.");
Marshal.WriteIntPtr(this.Address, this.pfnOriginal);
NativeFunctions.VirtualProtect(this.Address, (UIntPtr)Marshal.SizeOf<IntPtr>(), oldProtect, out _);
}
lock (HookManager.HookEnableSyncRoot)
{
*this.ppfnThunkJumpTarget = this.pfnOriginal;
this.enabled = false;
}
}
}