mirror of https://github.com/tongzx/nt5src
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
846 lines
22 KiB
846 lines
22 KiB
/*++
|
|
|
|
Copyright (c) 2000 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
StackSwap.cpp
|
|
|
|
Abstract:
|
|
|
|
Some applications make the assumption that Win32 APIs don't use any stack
|
|
space. This stems from the architecture of win9x - whereby many APIs
|
|
thunked and therefore had there own stack.
|
|
|
|
Of course on NT this isn't the case and many APIs are normal user mode
|
|
functions that don't even call down to kernel. To make matters worse, some
|
|
applications depend on *no* stack usage in a number of other ways, for
|
|
example:
|
|
|
|
1. Sierra Cart racing keeps a pointer in old stack
|
|
2. Baldur's Gate *double* dereferences pointers in old stack
|
|
3. NFL Blitz keeps it's linked lists on the stack and so simply calling
|
|
an API causes corruption
|
|
4. NFL Blitz 2000 runs out of stack space calling CreateFile
|
|
5. Interplay EReg has uninitialized variables on the stack which are
|
|
normally zeroed on win9x
|
|
|
|
This shim is parameterized and takes a list of APIs and the behavior of
|
|
each. Behavior is defined as the following:
|
|
|
|
- No stack is used by this API
|
|
0 - After API is called, old stack will be filled with zeroes
|
|
1 - After API is called, old stack will be filled with valid pointers
|
|
2 - After API is called, old stack will be filled with valid pointers
|
|
to pointers
|
|
|
|
The default is that no stack space is used by the API.
|
|
|
|
Notes:
|
|
|
|
This is a general purpose shim.
|
|
|
|
History:
|
|
|
|
05/03/2000 linstev Created
|
|
03/12/2001 robkenny Blessed for DBCS
|
|
|
|
--*/
|
|
|
|
#include "precomp.h"
|
|
|
|
// This module has been given an official blessing to use the str routines.
|
|
#include "LegalStr.h"
|
|
|
|
IMPLEMENT_SHIM_BEGIN(StackSwap)
|
|
#include "ShimHookMacro.h"
|
|
#include "ShimStack.h"
|
|
#include "StackSwap_Exports.h"
|
|
#include "StackSwap_Excludes.h"
|
|
|
|
APIHOOK_ENUM_BEGIN
|
|
APIHOOK_ENUM_ENTRY(CreateThread)
|
|
APIHOOK_ENUM_ENTRY(TerminateThread)
|
|
APIHOOK_ENUM_ENTRY(ExitThread)
|
|
APIHOOK_ENUM_END
|
|
|
|
|
|
#define THREAD_VAR Vdm // The TEB variable to overwrite
|
|
|
|
#define STUB_SIZE 64 // size of stub code in bytes
|
|
#define STACK_SIZE 65536 // size of temporary stack
|
|
#define STACK_COPY_SIZE 16 // number of dwords to copy from old stack
|
|
#define STACK_FILL_SIZE 256 // default number of dwords to fill
|
|
#define STACK_GUARD_SIZE 4096 // gaurd page at the top of the stack - must be a multiple of 4096
|
|
|
|
#define STACK_FILL_NONE -1 // no old stack filling
|
|
#define STACK_FILL_ZERO 0 // fill old stack with zeroes
|
|
#define STACK_FILL_PTR1 1 // fill old stack with pointers
|
|
#define STACK_FILL_PTR2 2 // fill old stack with pointers to pointers
|
|
|
|
PVOID g_dwZero = 0; // used for pointer to zero
|
|
PVOID g_dwPtr = &g_dwPtr; // used for pointer to pointer
|
|
|
|
PVOID g_arrFill[] =
|
|
{
|
|
0,
|
|
&g_dwZero,
|
|
&g_dwPtr
|
|
};
|
|
|
|
// Store for each hook returned by the parser
|
|
|
|
struct HOOK
|
|
{
|
|
char szModule[MAX_PATH]; // Module name
|
|
char szFnName[MAX_PATH]; // Function name
|
|
PVOID pfnNew; // Pointer to stub
|
|
DWORD dwFill; // Stack fill type
|
|
DWORD dwFillSize; // Number of dwords to fill
|
|
struct HOOK *next;
|
|
};
|
|
HOOK *g_pHooks = NULL;
|
|
|
|
HOOK g_AllHooks[] =
|
|
{
|
|
{"KERNEL32.DLL", "*", NULL, STACK_FILL_NONE},
|
|
{"GDI32.DLL", "*", NULL, STACK_FILL_NONE},
|
|
{"USER32.DLL", "*", NULL, STACK_FILL_NONE},
|
|
{"WINMM.DLL", "*", NULL, STACK_FILL_NONE}
|
|
};
|
|
|
|
DWORD dwStubCount = 0;
|
|
|
|
// Thread local data
|
|
|
|
typedef struct _THREAD_DATA
|
|
{
|
|
PVOID pfnHook; // Address of actual call
|
|
PVOID pNewStack; // The new stack
|
|
PVOID pOldStack; // The old stack
|
|
DWORD dwFill; // Fill method
|
|
DWORD dwFillSize; // Number of dwords to fill
|
|
ULONG ulCount; // Number of times we've entered
|
|
DWORD dwRet; // Return value
|
|
DWORD dwEcx, dwEsi, dwEdi; // Tempory storage, since we don't have a stack
|
|
} THREAD_DATA;
|
|
|
|
/*++
|
|
|
|
This function is called from the stubs. It's purpose is to give the API a new
|
|
stack to use. It does this by doing the following:
|
|
|
|
1. Copy the original stack to the new stack
|
|
2. Call the original hook
|
|
3. Copy the changed stack back to the original stack
|
|
4. Return control to the original caller
|
|
|
|
The only tricky things about this routine are that we don't want to use any
|
|
stack at all (no push/pop) and we need to calculate how much stack was used
|
|
for the parameters - something we don't know because we don't have the proto-
|
|
type.
|
|
|
|
If we really wanted to use push and pop, we could have set up a temporary
|
|
stack, but since we only need ecx, esi and edi, there didn't seem to be any
|
|
point.
|
|
|
|
--*/
|
|
|
|
__declspec(naked)
|
|
void
|
|
SwapStack()
|
|
{
|
|
__asm {
|
|
inc [eax + THREAD_DATA.ulCount] // increment counter
|
|
|
|
mov [eax + THREAD_DATA.dwEcx], ecx // backup ecx
|
|
mov [eax + THREAD_DATA.dwEsi], esi // backup esi
|
|
mov [eax + THREAD_DATA.dwEdi], edi // backup edi
|
|
|
|
mov ecx, [esp] // retrieve 'Hook' from Stub()
|
|
mov [eax + THREAD_DATA.pfnHook], ecx // which we got from the call
|
|
add esp, 4 // move the stack up to the return address
|
|
|
|
mov dword ptr [esp], offset SwapBack // fill in our new return address
|
|
|
|
lea edi, [esp + 4] // dst = new stack
|
|
mov esi, [eax + THREAD_DATA.pOldStack] // src = old stack
|
|
add esi, 4 // note the +4s since the first dword is the return address
|
|
|
|
cld // clear direction flag
|
|
mov ecx, STACK_COPY_SIZE - 1 // copy off STACK_COPY_SIZE - 1 bytes
|
|
rep movsd // do the copy
|
|
|
|
mov ecx, [eax + THREAD_DATA.dwEcx] // restore ecx
|
|
mov esi, [eax + THREAD_DATA.dwEsi] // restore esi
|
|
mov edi, [eax + THREAD_DATA.dwEdi] // restore edi
|
|
|
|
jmp [eax + THREAD_DATA.pfnHook] // jump back into the stub to do the actual
|
|
|
|
SwapBack:
|
|
|
|
mov [esp - 4], eax // unfortunately this is the only way to store the return
|
|
|
|
mov eax, fs:[0x18] // get the TEB
|
|
mov eax, [eax + TEB.THREAD_VAR] // get our thread local pointer
|
|
|
|
mov [eax + THREAD_DATA.dwEcx], ecx // backup ecx
|
|
mov [eax + THREAD_DATA.dwEsi], esi // backup esi
|
|
mov [eax + THREAD_DATA.dwEdi], edi // backup edi
|
|
|
|
mov ecx, [esp - 4] // get return value
|
|
mov [eax + THREAD_DATA.dwRet], ecx // store return value for later
|
|
|
|
mov ecx, esp // this is where we find out how many parameters were passed
|
|
sub ecx, [eax + THREAD_DATA.pNewStack] // on the stack - so we get the difference in ecx
|
|
|
|
mov edi, [eax + THREAD_DATA.pOldStack] // original stack
|
|
mov esi, [edi] // read the real return address
|
|
add edi, ecx // move the stack up, so we don't copy unnecessay stack
|
|
mov [edi - 4], esi // put the return address into edi-4: this is the only time we
|
|
// use app stack space at all
|
|
mov esp, edi
|
|
|
|
mov ecx, [eax + THREAD_DATA.dwFill] // test how we're going to fill
|
|
cmp ecx, STACK_FILL_NONE
|
|
jz FillDone
|
|
|
|
mov esi, [ecx*4 + g_arrFill] // value to fill with
|
|
|
|
lea edi, [esp - 8] // we're going to fill backwards, so esp-8 will skip the return address
|
|
mov ecx, [eax + THREAD_DATA.dwFillSize] // number of dwords to fill with
|
|
|
|
FillStack:
|
|
mov [edi], esi // store the value
|
|
sub edi, 4
|
|
dec ecx
|
|
jnz FillStack
|
|
|
|
FillDone:
|
|
|
|
mov ecx, [eax + THREAD_DATA.dwEcx] // restore ecx
|
|
mov esi, [eax + THREAD_DATA.dwEsi] // restore esi
|
|
mov edi, [eax + THREAD_DATA.dwEdi] // restore edi
|
|
|
|
dec [eax + THREAD_DATA.ulCount] // decrement counter
|
|
|
|
mov eax, [eax + THREAD_DATA.dwRet] // get the return value
|
|
jmp dword ptr [esp - 4] // return to original caller
|
|
}
|
|
}
|
|
|
|
//
|
|
// We need the stub to do a far call to SwapStack since the stub will move, but
|
|
// I can't seem to force the far call without this method
|
|
//
|
|
|
|
DWORD_PTR g_pfnStackSwap = (DWORD_PTR)SwapStack;
|
|
|
|
/*++
|
|
|
|
This is the stub function that is called by every API. It is copied from here
|
|
to blocks of executable memory and the calls and fill types are written to
|
|
hard coded addresses within it.
|
|
|
|
The instuctions:
|
|
|
|
mov [eax + THREAD_DATA.dwFill], 0xFFFFFFFF is replaced by
|
|
mov [eax + THREAD_DATA.dwFill], FILL_TYPE
|
|
mov [eax + THREAD_DATA.dwFillSize], 0xFFFFFFFF is replaced by
|
|
mov [eax + THREAD_DATA.dwFill], FILL_SIZE
|
|
|
|
and
|
|
|
|
call g_pfnStackSwap is replaced by
|
|
call g_pAPIHooks[api].pfnOld
|
|
|
|
--*/
|
|
|
|
__declspec(naked)
|
|
void
|
|
Stub()
|
|
{
|
|
__asm {
|
|
mov eax, fs:[0x18] // get the TEB
|
|
mov eax, [eax + TEB.THREAD_VAR] // get our thread local pointer
|
|
|
|
or eax, eax // our pointer is gone
|
|
jz Hook // exit gracefully
|
|
|
|
cmp [eax + THREAD_DATA.ulCount], 0 // have we already swapped the stack
|
|
jnz Hook
|
|
|
|
mov [eax + THREAD_DATA.dwFill], 0xFFFFFFFF // the 0xFFFFFFFF will be replaced by the fill type
|
|
mov [eax + THREAD_DATA.dwFillSize], 0xFFFFFFFF // the 0xFFFFFFFF will be replaced by the fill size
|
|
mov [eax + THREAD_DATA.pOldStack], esp // backup the old stack
|
|
mov esp, [eax + THREAD_DATA.pNewStack] // swap the stack
|
|
call g_pfnStackSwap // call into the stack swapping code
|
|
|
|
Hook:
|
|
jmp [g_pHooks] // jump to the hook
|
|
}
|
|
}
|
|
|
|
/*++
|
|
|
|
Create a new stack
|
|
|
|
--*/
|
|
|
|
THREAD_DATA *
|
|
AllocStack()
|
|
{
|
|
LPVOID p = VirtualAlloc(
|
|
0,
|
|
sizeof(THREAD_DATA) + STACK_SIZE + STACK_GUARD_SIZE,
|
|
MEM_COMMIT,
|
|
PAGE_READWRITE);
|
|
|
|
if (p)
|
|
{
|
|
DWORD dwOld;
|
|
if (!VirtualProtect(p, STACK_GUARD_SIZE, PAGE_READONLY | PAGE_GUARD, &dwOld))
|
|
{
|
|
DPFN( eDbgLevelError, "Failed to place Gaurd page at the top of the stack");
|
|
}
|
|
|
|
THREAD_DATA *pTD = (THREAD_DATA *)((DWORD_PTR)p + STACK_SIZE + STACK_GUARD_SIZE);
|
|
|
|
pTD->pNewStack = (LPVOID)((DWORD_PTR)pTD - STACK_COPY_SIZE * 4);
|
|
|
|
return pTD;
|
|
}
|
|
else
|
|
{
|
|
DPFN( eDbgLevelError, "Failed to allocate new stack");
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/*++
|
|
|
|
Free the stack
|
|
|
|
--*/
|
|
|
|
BOOL
|
|
FreeStack(THREAD_DATA *pTD)
|
|
{
|
|
BOOL bRet = FALSE;
|
|
|
|
if (pTD)
|
|
{
|
|
LPVOID p = (LPVOID)((DWORD_PTR)pTD - STACK_SIZE - STACK_GUARD_SIZE);
|
|
bRet = VirtualFree(p, 0, MEM_RELEASE);
|
|
}
|
|
|
|
if (!bRet)
|
|
{
|
|
DPFN( eDbgLevelError, "Failed to free a stack");
|
|
}
|
|
|
|
return bRet;
|
|
}
|
|
|
|
/*++
|
|
|
|
Hook CreateThread so we can add our stuff to the TEB.
|
|
|
|
--*/
|
|
|
|
HANDLE
|
|
APIHOOK(CreateThread)(
|
|
LPSECURITY_ATTRIBUTES lpThreadAttributes,
|
|
DWORD dwStackSize,
|
|
LPTHREAD_START_ROUTINE lpStartAddress,
|
|
LPVOID lpParameter,
|
|
DWORD dwCreationFlags,
|
|
LPDWORD lpThreadId
|
|
)
|
|
{
|
|
HANDLE hRet;
|
|
DWORD dwFlags = dwCreationFlags;
|
|
|
|
NEW_STACK();
|
|
|
|
hRet = ORIGINAL_API(CreateThread)(
|
|
lpThreadAttributes,
|
|
dwStackSize,
|
|
lpStartAddress,
|
|
lpParameter,
|
|
dwCreationFlags | CREATE_SUSPENDED,
|
|
lpThreadId);
|
|
|
|
if (hRet)
|
|
{
|
|
THREAD_BASIC_INFORMATION tbi;
|
|
NTSTATUS Status;
|
|
|
|
Status = NtQueryInformationThread(
|
|
hRet,
|
|
ThreadBasicInformation,
|
|
&tbi,
|
|
sizeof(tbi),
|
|
NULL);
|
|
|
|
if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
|
|
{
|
|
tbi.TebBaseAddress->THREAD_VAR = AllocStack();
|
|
}
|
|
|
|
if (!(dwFlags & CREATE_SUSPENDED))
|
|
{
|
|
ResumeThread(hRet);
|
|
}
|
|
}
|
|
|
|
OLD_STACK();
|
|
|
|
return hRet;
|
|
}
|
|
|
|
/*++
|
|
|
|
Hook TerminateThread so we can clean up the thread local data.
|
|
|
|
--*/
|
|
|
|
BOOL
|
|
APIHOOK(TerminateThread)(
|
|
HANDLE hThread,
|
|
DWORD dwExitCode
|
|
)
|
|
{
|
|
THREAD_BASIC_INFORMATION tbi;
|
|
NTSTATUS Status;
|
|
BOOL bRet;
|
|
THREAD_DATA *pTD = NULL;
|
|
|
|
Status = NtQueryInformationThread(
|
|
hThread,
|
|
ThreadBasicInformation,
|
|
&tbi,
|
|
sizeof(tbi),
|
|
NULL);
|
|
|
|
if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
|
|
{
|
|
pTD = (THREAD_DATA *)(tbi.TebBaseAddress->THREAD_VAR);
|
|
}
|
|
|
|
bRet = ORIGINAL_API(TerminateThread)(hThread, dwExitCode);
|
|
|
|
FreeStack(pTD);
|
|
|
|
return bRet;
|
|
}
|
|
|
|
/*++
|
|
|
|
Hook ExitThread so we can clean up the thread local data.
|
|
|
|
--*/
|
|
|
|
VOID
|
|
APIHOOK(ExitThread)(
|
|
DWORD dwExitCode
|
|
)
|
|
{
|
|
NTSTATUS Status;
|
|
THREAD_BASIC_INFORMATION tbi;
|
|
HANDLE hThread = GetCurrentThread();
|
|
|
|
Status = NtQueryInformationThread(
|
|
hThread,
|
|
ThreadBasicInformation,
|
|
&tbi,
|
|
sizeof(tbi),
|
|
NULL);
|
|
|
|
if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
|
|
{
|
|
THREAD_DATA *pTD = (THREAD_DATA *)tbi.TebBaseAddress->THREAD_VAR;
|
|
|
|
// Make sure we don't free it if we're using it
|
|
if (pTD && (pTD->ulCount == 0))
|
|
{
|
|
FreeStack(pTD);
|
|
}
|
|
}
|
|
|
|
ORIGINAL_API(ExitThread)(dwExitCode);
|
|
}
|
|
|
|
/*++
|
|
|
|
Add the specified hook to the linked list - this accepts wildcards.
|
|
|
|
--*/
|
|
|
|
VOID
|
|
AddHooks(HOOK *pHook)
|
|
{
|
|
if (strstr(pHook->szFnName, "*") == 0)
|
|
{
|
|
// Now that we have a hook (not a wild card), we need to make sure it's
|
|
// ok to add it to the list. There are some calls that cannot be shimmed
|
|
|
|
for (int i=0; i<sizeof(Excludes)/sizeof(FNEXCLUDE); i++)
|
|
{
|
|
if ((_stricmp(pHook->szModule, (LPSTR)Excludes[i].pszModule) == 0) &&
|
|
(strcmp(pHook->szFnName, (LPSTR)Excludes[i].pszFnName) == 0))
|
|
{
|
|
DPFN( eDbgLevelInfo,"Ignoring %s!%s", Excludes[i].pszModule, Excludes[i].pszFnName);
|
|
return;
|
|
}
|
|
}
|
|
|
|
// The hook passes, so add it to the list.
|
|
|
|
HOOK *pH = (HOOK *) malloc(sizeof(HOOK));
|
|
if (pH)
|
|
{
|
|
MoveMemory(pH, pHook, sizeof(HOOK));
|
|
pH->next = g_pHooks;
|
|
g_pHooks = pH;
|
|
}
|
|
return;
|
|
}
|
|
|
|
// Here we have to look through the exports
|
|
LOADED_IMAGE image;
|
|
|
|
if (!LoadModule(pHook->szModule, &image))
|
|
{
|
|
DPFN( eDbgLevelError, "Module %s not found", pHook->szModule);
|
|
return;
|
|
}
|
|
|
|
EXPORT_ENUM exports;
|
|
CHAR szFnName[MAX_PATH];
|
|
|
|
strcpy(szFnName, pHook->szFnName);
|
|
|
|
DWORD dwLen = (DWORD)((DWORD_PTR)strstr(pHook->szFnName, "*") - (DWORD_PTR)&pHook->szFnName);
|
|
|
|
// Enumerate the exports for this module
|
|
|
|
BOOL bMore = EnumFirstExport(&image, &exports);
|
|
while (bMore)
|
|
{
|
|
if ((dwLen == 0) ||
|
|
(strncmp(exports.ExportFunction, szFnName, dwLen) == 0))
|
|
{
|
|
// We have a match
|
|
strcpy(pHook->szFnName, exports.ExportFunction);
|
|
AddHooks(pHook);
|
|
}
|
|
|
|
bMore = EnumNextExport(&exports);
|
|
}
|
|
|
|
// Done with this module
|
|
UnloadModule(&image);
|
|
}
|
|
|
|
/*++
|
|
|
|
Parse the command line for APIs to fix stack problems with:
|
|
|
|
USER32.DLL!GetDC:0; KERNEL32.DLL!CreateFile*
|
|
|
|
The :X is to define behaviour - so:
|
|
|
|
:0 fill old stack with zeroes
|
|
:1 fill old stack with pointers
|
|
:2 fill old stack with pointers to pointers
|
|
|
|
--*/
|
|
|
|
DWORD
|
|
ParseCommandLineA(
|
|
LPCSTR lpCommandLine
|
|
)
|
|
{
|
|
char seps[] = " :,\t;!";
|
|
char *token = NULL;
|
|
HOOK *pHook = NULL;
|
|
DWORD dwState = 0;
|
|
HOOK hook;
|
|
|
|
// Since strtok modifies the string, we need to copy it
|
|
LPSTR szCommandLine = (LPSTR) malloc(strlen(lpCommandLine) + 1);
|
|
if (!szCommandLine) goto Exit;
|
|
|
|
strcpy(szCommandLine, lpCommandLine);
|
|
|
|
//
|
|
// See if we need to do all modules
|
|
//
|
|
|
|
if ((strcmp(szCommandLine, "") == 0) || (strcmp(szCommandLine, "*") == 0))
|
|
{
|
|
for (int i=0; i<sizeof(g_AllHooks)/sizeof(HOOK); i++)
|
|
{
|
|
AddHooks(&g_AllHooks[i]);
|
|
}
|
|
goto Exit;
|
|
}
|
|
|
|
//
|
|
// Run the string, looking for exception names
|
|
//
|
|
|
|
token = _strtok(szCommandLine, seps);
|
|
|
|
while (token)
|
|
{
|
|
switch (dwState)
|
|
{
|
|
case 2: // handle the :X[(fill size)] case
|
|
dwState = 0;
|
|
|
|
if (token[0] && ((token[1] == '\0') || (token[1] == '(')))
|
|
{
|
|
switch (token[0])
|
|
{
|
|
case '0':
|
|
hook.dwFill = STACK_FILL_ZERO;
|
|
break;
|
|
case '1':
|
|
hook.dwFill = STACK_FILL_PTR1;
|
|
break;
|
|
case '2':
|
|
hook.dwFill = STACK_FILL_PTR2;
|
|
break;
|
|
default:
|
|
hook.dwFill = STACK_FILL_ZERO;
|
|
}
|
|
|
|
if (token[1] == '(')
|
|
{
|
|
token+=2; // advance to the beginning of the fill size
|
|
token[strlen(token)-1] = '\0'; // null terminate
|
|
hook.dwFillSize = atol(token) >> 2; // get fill size in dwords
|
|
if (hook.dwFillSize == 0)
|
|
{
|
|
hook.dwFillSize = STACK_FILL_SIZE;
|
|
}
|
|
}
|
|
|
|
// We must be done, so add this hook
|
|
AddHooks(&hook);
|
|
|
|
break;
|
|
}
|
|
|
|
AddHooks(&hook);
|
|
|
|
case 0: // add a new API module name
|
|
ZeroMemory(&hook, sizeof(HOOK));
|
|
strcpy(hook.szModule, token);
|
|
hook.dwFill = STACK_FILL_NONE;
|
|
hook.dwFillSize = STACK_FILL_SIZE;
|
|
dwState++;
|
|
|
|
break;
|
|
|
|
case 1: // add a new API function name
|
|
dwState++;
|
|
|
|
if (strlen(hook.szModule) == 0)
|
|
{
|
|
DPFN( eDbgLevelError, "Parse error with token %s", token);
|
|
goto Exit;
|
|
}
|
|
|
|
strcpy(hook.szFnName, token);
|
|
break;
|
|
}
|
|
|
|
// Get the next token
|
|
token = _strtok(NULL, seps);
|
|
}
|
|
|
|
if (dwState == 2)
|
|
{
|
|
AddHooks(&hook);
|
|
}
|
|
|
|
Exit:
|
|
if (szCommandLine)
|
|
{
|
|
free(szCommandLine);
|
|
}
|
|
|
|
if (!g_pHooks)
|
|
{
|
|
DPFN( eDbgLevelError, "No hooks added");
|
|
return 0;
|
|
}
|
|
|
|
//
|
|
// Dump results of command line parse
|
|
//
|
|
|
|
DPFN( eDbgLevelInfo, "--------------------------------------------");
|
|
DPFN( eDbgLevelInfo, " Stack Swapping the following APIs: ");
|
|
DPFN( eDbgLevelInfo, "--------------------------------------------");
|
|
|
|
DWORD dwCount = 0;
|
|
pHook = g_pHooks;
|
|
while (pHook)
|
|
{
|
|
DPFN( eDbgLevelInfo, "%s!%s: Fill=%d, Size=%d", pHook->szModule, pHook->szFnName, pHook->dwFill, pHook->dwFillSize*4);
|
|
dwCount++;
|
|
pHook = pHook->next;
|
|
}
|
|
DPFN( eDbgLevelInfo, "--------------------------------------------");
|
|
|
|
return dwCount;
|
|
}
|
|
|
|
/*++
|
|
|
|
Builds the stubs for the hooked APIs
|
|
|
|
--*/
|
|
|
|
DWORD
|
|
BuildStubs()
|
|
{
|
|
// Count the stubs
|
|
DWORD dwCount = 0;
|
|
HOOK *pHook = g_pHooks;
|
|
while (pHook)
|
|
{
|
|
dwCount++;
|
|
pHook = pHook->next;
|
|
}
|
|
|
|
// Create the stubs
|
|
LPBYTE pStub = (LPBYTE) VirtualAlloc(
|
|
0,
|
|
STUB_SIZE * dwCount,
|
|
MEM_COMMIT,
|
|
PAGE_EXECUTE_READWRITE);
|
|
|
|
if (!pStub)
|
|
{
|
|
DPFN( eDbgLevelError, "Could not allocate memory for stubs");
|
|
return 0;
|
|
}
|
|
|
|
pHook = g_pHooks;
|
|
PHOOKAPI pAPIHook = &g_pAPIHooks[APIHOOK_Count];
|
|
while (pHook)
|
|
{
|
|
MoveMemory(pStub, Stub, STUB_SIZE);
|
|
|
|
LPDWORD p;
|
|
|
|
p = (LPDWORD)((DWORD_PTR)pStub + 0x19); // fill in the fill type
|
|
*p = pHook->dwFill;
|
|
|
|
p = (LPDWORD)((DWORD_PTR)pStub + 0x19+7); // fill in the fill size
|
|
*p = pHook->dwFillSize;
|
|
|
|
p = (LPDWORD)((DWORD_PTR)pStub + 0x2b+7); // fill in the hook
|
|
*p = (DWORD_PTR)&pAPIHook->pfnOld;
|
|
|
|
ZeroMemory(pAPIHook, sizeof(HOOKAPI));
|
|
pAPIHook->pszModule = pHook->szModule;
|
|
pAPIHook->pszFunctionName = pHook->szFnName;
|
|
pAPIHook->pfnNew = pStub;
|
|
|
|
DPFN( eDbgLevelSpew, "%08lx %s!%s", pStub, pHook->szModule, pHook->szFnName);
|
|
|
|
pStub += STUB_SIZE;
|
|
pAPIHook++;
|
|
pHook = pHook->next;
|
|
}
|
|
|
|
return dwCount;
|
|
}
|
|
|
|
/*++
|
|
|
|
Free the stub list allocated by ParseCommandLineA
|
|
|
|
--*/
|
|
|
|
VOID
|
|
FreeStubs()
|
|
{
|
|
HOOK *pHook = g_pHooks;
|
|
|
|
while (pHook)
|
|
{
|
|
pHook = pHook->next;
|
|
free(g_pHooks);
|
|
g_pHooks = pHook;
|
|
}
|
|
}
|
|
|
|
/*++
|
|
|
|
Register hooked functions
|
|
|
|
--*/
|
|
|
|
BOOL
|
|
NOTIFY_FUNCTION(DWORD fdwReason)
|
|
{
|
|
if (fdwReason == DLL_PROCESS_ATTACH)
|
|
{
|
|
// Run the command line to check for hooks - returns number found
|
|
dwStubCount = ParseCommandLineA(COMMAND_LINE);
|
|
|
|
if (dwStubCount)
|
|
{
|
|
//
|
|
// Increase the hook structure size.
|
|
//
|
|
|
|
g_pAPIHooks = (PHOOKAPI) realloc(g_pAPIHooks,
|
|
sizeof(HOOKAPI) * (APIHOOK_Count + dwStubCount));
|
|
|
|
if (!g_pAPIHooks)
|
|
{
|
|
DPFN( eDbgLevelError, "Failed to re-allocate hooks");
|
|
return FALSE;
|
|
}
|
|
}
|
|
|
|
INIT_STACK(1024 * 128, 32);
|
|
|
|
NtCurrentTeb()->THREAD_VAR = AllocStack();
|
|
|
|
BuildStubs();
|
|
}
|
|
else if (fdwReason == DLL_PROCESS_DETACH)
|
|
{
|
|
// Ignore cleanup
|
|
// FreeStubs();
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
HOOK_BEGIN
|
|
|
|
CALL_NOTIFY_FUNCTION
|
|
|
|
APIHOOK_ENTRY(KERNEL32.DLL, CreateThread)
|
|
APIHOOK_ENTRY(KERNEL32.DLL, TerminateThread)
|
|
APIHOOK_ENTRY(KERNEL32.DLL, ExitThread)
|
|
|
|
if (fdwReason == DLL_PROCESS_ATTACH)
|
|
{
|
|
// Write out the new size
|
|
*pdwHookCount = APIHOOK_Count + dwStubCount;
|
|
}
|
|
|
|
HOOK_END
|
|
|
|
IMPLEMENT_SHIM_END
|