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HLMetaModOfficial/core/sourcehook/sh_memory.h

368 lines
8.6 KiB
C++

/* ======== SourceHook ========
* Copyright (C) 2004-2010 Metamod:Source Development Team
* No warranties of any kind
*
* License: zlib/libpng
*
* Author(s): Pavol "PM OnoTo" Marko, Scott "Damaged Soul" Ehlert
* Contributors: lancevorgin, XAD, theqizmo
* ============================
*/
#ifndef __SHINT_MEMORY_H__
#define __SHINT_MEMORY_H__
// Feb 17 / 2005:
// Unprotect now sets to readwrite
// The vtable doesn't need to be executable anyway
# if SH_XP == SH_XP_WINAPI
# include <windows.h>
# define SH_MEM_READ 1
# define SH_MEM_WRITE 2
# define SH_MEM_EXEC 4
# elif SH_XP == SH_XP_POSIX
# include <sys/mman.h>
# include <stdio.h>
# include <signal.h>
# include <setjmp.h>
# include <stdint.h>
// http://www.die.net/doc/linux/man/man2/mprotect.2.html
# include <limits.h>
# ifndef PAGESIZE
# define PAGESIZE 4096
# endif
# define SH_MEM_READ PROT_READ
# define SH_MEM_WRITE PROT_WRITE
# define SH_MEM_EXEC PROT_EXEC
// We need to align addr down to pagesize on linux
// We assume PAGESIZE is a power of two
# define SH_LALIGN(x) (void*)((uintptr_t)(x) & ~(PAGESIZE-1))
# define SH_LALDIF(x) ((uintptr_t)(x) % PAGESIZE)
# else
# error Unsupported OS/Compiler
# endif
#if SH_SYS == SH_SYS_APPLE
# include <mach/mach.h>
# include <mach/vm_region.h>
# include <mach/mach_traps.h>
#endif
#include "sh_list.h"
namespace SourceHook
{
static inline bool GetPageBits(void *addr, int *bits)
{
#if SH_SYS == SH_SYS_LINUX
// On linux, first check /proc/self/maps
unsigned long laddr = reinterpret_cast<unsigned long>(addr);
FILE *pF = fopen("/proc/self/maps", "r");
if (pF) {
// Linux /proc/self/maps -> parse
// Format:
// lower upper prot stuff path
// 08048000-0804c000 r-xp 00000000 03:03 1010107 /bin/cat
unsigned long rlower, rupper;
char r, w, x;
while (fscanf(pF, "%lx-%lx %c%c%c", &rlower, &rupper, &r, &w, &x) != EOF) {
// Check whether we're IN THERE!
if (laddr >= rlower && laddr < rupper) {
fclose(pF);
*bits = 0;
if (r == 'r')
*bits |= SH_MEM_READ;
if (w == 'w')
*bits |= SH_MEM_WRITE;
if (x == 'x')
*bits |= SH_MEM_EXEC;
return true;
}
// Read to end of line
int c;
while ((c = fgetc(pF)) != '\n') {
if (c == EOF)
break;
}
if (c == EOF)
break;
}
fclose(pF);
return false;
}
pF = fopen("/proc/curproc/map", "r");
if (pF) {
// FreeBSD /proc/curproc/map -> parse
// 0x804800 0x805500 13 15 0xc6e18960 r-x 21 0x0 COW NC vnode
unsigned long rlower, rupper, ignoreLong;
int ignoreInt;
char r, w, x;
while (fscanf(pF, "0x%lx 0x%lx %d %d 0x%lx %c%c%c", &rlower, &rupper, &ignoreInt,
&ignoreInt, &ignoreLong, &r, &w, &x) != EOF) {
// Check whether we're IN THERE!
if (laddr >= rlower && laddr < rupper) {
fclose(pF);
*bits = 0;
if (r == 'r')
*bits |= SH_MEM_READ;
if (r == 'w')
*bits |= SH_MEM_WRITE;
if (r == 'x')
*bits |= SH_MEM_EXEC;
return true;
}
// Read to end of line
int c;
while ((c = fgetc(pF)) != '\n') {
if (c == EOF)
break;
}
if (c == EOF)
break;
}
fclose(pF);
return false;
}
return false;
#elif SH_SYS == SH_SYS_APPLE
vm_size_t ignoreSize;
vm_address_t vmaddr = (vm_address_t)addr;
vm_region_basic_info_data_t info;
vm_region_flavor_t flavor = VM_REGION_BASIC_INFO;
memory_object_name_t obj;
mach_msg_type_number_t count = VM_REGION_BASIC_INFO_COUNT;
kern_return_t kr = vm_region(mach_task_self(), &vmaddr, &ignoreSize, flavor,
(vm_region_info_t)&info, &count, &obj);
if (kr != KERN_SUCCESS)
return false;
*bits = 0;
if (info.protection & VM_PROT_READ)
*bits |= SH_MEM_READ;
if (info.protection & VM_PROT_WRITE)
*bits |= SH_MEM_WRITE;
if (info.protection & VM_PROT_EXECUTE)
*bits |= SH_MEM_EXEC;
return true;
#elif SH_XP == SH_XP_WINAPI
SYSTEM_INFO info;
GetSystemInfo(&info);
MEMORY_BASIC_INFORMATION mem;
size_t base = size_t(addr) & ~size_t(info.dwPageSize - 1);
if (!VirtualQuery((void *)base, &mem, sizeof(mem)))
return false;
switch (mem.Protect) {
case PAGE_EXECUTE:
*bits = SH_MEM_EXEC;
break;
case PAGE_EXECUTE_READ:
*bits = SH_MEM_EXEC | SH_MEM_READ;
break;
case PAGE_EXECUTE_READWRITE:
case PAGE_EXECUTE_WRITECOPY:
*bits = SH_MEM_EXEC | SH_MEM_READ | SH_MEM_WRITE;
break;
case PAGE_NOACCESS:
*bits = 0;
break;
case PAGE_READONLY:
*bits = SH_MEM_READ;
break;
case PAGE_READWRITE:
case PAGE_WRITECOPY:
*bits = SH_MEM_READ | SH_MEM_WRITE;
break;
default:
return false;
}
return true;
#endif
}
inline bool SetMemAccess(void *addr, size_t len, int access)
{
# if SH_XP == SH_XP_POSIX
return mprotect(SH_LALIGN(addr), len + SH_LALDIF(addr), access)==0 ? true : false;
# elif SH_XP == SH_XP_WINAPI
DWORD tmp;
DWORD prot;
switch (access)
{
case SH_MEM_READ:
prot = PAGE_READONLY; break;
case SH_MEM_READ | SH_MEM_WRITE:
prot = PAGE_READWRITE; break;
case SH_MEM_READ | SH_MEM_EXEC:
prot = PAGE_EXECUTE_READ; break;
default:
case SH_MEM_READ | SH_MEM_WRITE | SH_MEM_EXEC:
prot = PAGE_EXECUTE_READWRITE; break;
}
return VirtualProtect(addr, len, prot, &tmp) ? true : false;
# endif
}
inline bool MakePageWritable(void *addr)
{
int bits;
if (GetPageBits(addr, &bits)) {
if (bits & SH_MEM_WRITE)
return true;
bits |= SH_MEM_WRITE;
} else {
bits = SH_MEM_READ | SH_MEM_WRITE | SH_MEM_EXEC;
}
return SetMemAccess(addr, sizeof(void *), bits);
}
#if SH_XP == SH_XP_POSIX
namespace
{
bool g_BadReadCalled;
jmp_buf g_BadReadJmpBuf;
# if SH_SYS == SH_SYS_LINUX
static void BadReadHandler(int sig)
{
if (g_BadReadCalled)
longjmp(g_BadReadJmpBuf, 1);
}
# elif SH_SYS == SH_SYS_APPLE
static void BadReadHandler(int signal, siginfo_t* my_siginfo, void* my_context)
{
if (g_BadReadCalled)
longjmp(g_BadReadJmpBuf, 1);
}
# endif
}
#endif
/**
* @brief Checks whether the specified memory region is (still) accessible
*
* @param addr The lower boundary
* @param len Length of the region to be checked
*/
namespace
{
bool ModuleInMemory(char *addr, size_t len)
{
#if SH_SYS == SH_SYS_LINUX
// On linux, first check /proc/self/maps
long lower = reinterpret_cast<long>(addr);
long upper = lower + len;
FILE *pF = fopen("/proc/self/maps", "r");
if (pF)
{
// Linux /proc/self/maps -> parse
// Format:
// lower upper prot stuff path
// 08048000-0804c000 r-xp 00000000 03:03 1010107 /bin/cat
long rlower, rupper;
while (fscanf(pF, "%lx-%lx", &rlower, &rupper) != EOF)
{
// Check whether we're IN THERE!
if (lower >= rlower && upper <= rupper)
{
fclose(pF);
return true;
}
// Read to end of line
int c;
while ((c = fgetc(pF)) != '\n')
{
if (c == EOF)
break;
}
if (c == EOF)
break;
}
fclose(pF);
return false;
}
pF = fopen("/proc/curproc/map", "r");
if (pF)
{
// FreeBSD /proc/curproc/map -> parse
// 0x804800 0x805500 13 15 0xc6e18960 r-x 21 0x0 COW NC vnode
long rlower, rupper;
while (fscanf(pF, "0x%lx 0x%lx", &rlower, &rupper) != EOF)
{
// Check whether we're IN THERE!
if (lower >= rlower && upper <= rupper)
{
fclose(pF);
return true;
}
// Read to end of line
int c;
while ((c = fgetc(pF)) != '\n')
{
if (c == EOF)
break;
}
if (c == EOF)
break;
}
fclose(pF);
return false;
}
// Both of the above failed, try to actually read and trap sigsegv (implemented by Damaged Soul)
void(*prevHandler)(int sig);
g_BadReadCalled = true;
if (setjmp(g_BadReadJmpBuf))
return true;
prevHandler = signal(SIGSEGV, BadReadHandler);
volatile const char *p = reinterpret_cast<const char*>(addr);
char dummy;
for (size_t i = 0; i < len; i++)
dummy = p[i];
g_BadReadCalled = false;
signal(SIGSEGV, prevHandler);
return false;
#elif SH_SYS == SH_SYS_APPLE
struct sigaction sa, osa;
sa.sa_sigaction = BadReadHandler;
sa.sa_flags = SA_SIGINFO | SA_RESTART;
g_BadReadCalled = true;
if (setjmp(g_BadReadJmpBuf))
return false;
if (sigaction(SIGBUS, &sa, &osa) == -1)
return false;
volatile const char *p = reinterpret_cast<const char *>(addr);
char dummy;
for (size_t i = 0; i < len; i++)
dummy = p[i];
g_BadReadCalled = false;
sigaction(SIGBUS, &osa, NULL);
return true;
#elif SH_XP == SH_XP_WINAPI
// On Win32, simply use IsBadReadPtr
return !IsBadReadPtr(addr, len);
#endif
}
}
}
#endif