140 lines
4.2 KiB
C
140 lines
4.2 KiB
C
/**
|
|
* vim: set ts=4 :
|
|
* =============================================================================
|
|
* SourceMod
|
|
* Copyright (C) 2004-2010 AlliedModders LLC. All rights reserved.
|
|
* =============================================================================
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it under
|
|
* the terms of the GNU General Public License, version 3.0, as published by the
|
|
* Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
|
|
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
|
|
* details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along with
|
|
* this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*
|
|
* As a special exception, AlliedModders LLC gives you permission to link the
|
|
* code of this program (as well as its derivative works) to "Half-Life 2," the
|
|
* "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
|
|
* by the Valve Corporation. You must obey the GNU General Public License in
|
|
* all respects for all other code used. Additionally, AlliedModders LLC grants
|
|
* this exception to all derivative works. AlliedModders LLC defines further
|
|
* exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
|
|
* or <http://www.sourcemod.net/license.php>.
|
|
*
|
|
* Version: $Id: detourhelpers.h 248 2008-08-27 00:56:22Z pred $
|
|
*/
|
|
|
|
#ifndef _INCLUDE_SOURCEMOD_DETOURHELPERS_H_
|
|
#define _INCLUDE_SOURCEMOD_DETOURHELPERS_H_
|
|
|
|
#if defined PLATFORM_POSIX
|
|
#include <sys/mman.h>
|
|
#ifndef PAGE_SIZE
|
|
#define PAGE_SIZE 4096
|
|
#endif
|
|
#define ALIGN(ar) ((long)ar & ~(PAGE_SIZE-1))
|
|
#define PAGE_EXECUTE_READWRITE PROT_READ|PROT_WRITE|PROT_EXEC
|
|
#endif
|
|
|
|
#include <jit/x86/x86_macros.h>
|
|
|
|
struct patch_t
|
|
{
|
|
patch_t()
|
|
{
|
|
patch[0] = 0;
|
|
bytes = 0;
|
|
}
|
|
unsigned char patch[20];
|
|
size_t bytes;
|
|
};
|
|
|
|
inline void ProtectMemory(void *addr, int length, int prot)
|
|
{
|
|
#if defined PLATFORM_POSIX
|
|
void *addr2 = (void *)ALIGN(addr);
|
|
mprotect(addr2, sysconf(_SC_PAGESIZE), prot);
|
|
#elif defined PLATFORM_WINDOWS
|
|
DWORD old_prot;
|
|
VirtualProtect(addr, length, prot, &old_prot);
|
|
#endif
|
|
}
|
|
|
|
inline void SetMemPatchable(void *address, size_t size)
|
|
{
|
|
ProtectMemory(address, (int)size, PAGE_EXECUTE_READWRITE);
|
|
}
|
|
|
|
inline void PatchRelJump32(unsigned char *target, void *callback)
|
|
{
|
|
SetMemPatchable(target, 5);
|
|
|
|
// jmp <32-bit displacement>
|
|
target[0] = IA32_JMP_IMM32;
|
|
*(int32_t *)(&target[1]) = int32_t((unsigned char *)callback - (target + 5));
|
|
}
|
|
|
|
inline void PatchAbsJump64(unsigned char *target, void *callback)
|
|
{
|
|
int i = 0;
|
|
SetMemPatchable(target, 14);
|
|
|
|
// push <lower 32-bits> ; allocates 64-bit stack space on x64
|
|
// mov [rsp+4], <upper 32-bits> ; unnecessary if upper bits are 0
|
|
// ret ; jump to address on stack
|
|
target[i++] = IA32_PUSH_IMM32;
|
|
*(int32_t *)(&target[i]) = int32_t(int64_t(callback));
|
|
i += 4;
|
|
if ((int64_t(callback) >> 32) != 0)
|
|
{
|
|
target[i++] = IA32_MOV_RM_IMM32;
|
|
target[i++] = ia32_modrm(MOD_DISP8, 0, kREG_SIB);
|
|
target[i++] = ia32_sib(NOSCALE, kREG_NOIDX, kREG_ESP);
|
|
target[i++] = 0x04;
|
|
*(int32_t *)(&target[i]) = (int64_t(callback) >> 32);
|
|
i += 4;
|
|
}
|
|
target[i] = IA32_RET;
|
|
}
|
|
|
|
inline void DoGatePatch(unsigned char *target, void *callback)
|
|
{
|
|
#if defined(_WIN64) || defined(__x86_64__)
|
|
int64_t diff = int64_t(callback) - (int64_t(target) + 5);
|
|
int32_t upperBits = (diff >> 32);
|
|
if (upperBits == 0 || upperBits == -1)
|
|
PatchRelJump32(target, callback);
|
|
else
|
|
PatchAbsJump64(target, callback);
|
|
#else
|
|
PatchRelJump32(target, callback);
|
|
#endif
|
|
}
|
|
|
|
inline void ApplyPatch(void *address, int offset, const patch_t *patch, patch_t *restore)
|
|
{
|
|
ProtectMemory(address, 20, PAGE_EXECUTE_READWRITE);
|
|
|
|
unsigned char *addr = (unsigned char *)address + offset;
|
|
if (restore)
|
|
{
|
|
for (size_t i=0; i<patch->bytes; i++)
|
|
{
|
|
restore->patch[i] = addr[i];
|
|
}
|
|
restore->bytes = patch->bytes;
|
|
}
|
|
|
|
for (size_t i=0; i<patch->bytes; i++)
|
|
{
|
|
addr[i] = patch->patch[i];
|
|
}
|
|
}
|
|
|
|
#endif //_INCLUDE_SOURCEMOD_DETOURHELPERS_H_
|