865 lines
24 KiB
C++
865 lines
24 KiB
C++
/*++
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Copyright (c) 2000 Microsoft Corporation
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Module Name:
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StackSwap.cpp
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Abstract:
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Some applications make the assumption that Win32 APIs don't use any stack
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space. This stems from the architecture of win9x - whereby many APIs
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thunked and therefore had there own stack.
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Of course on NT this isn't the case and many APIs are normal user mode
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functions that don't even call down to kernel. To make matters worse, some
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applications depend on *no* stack usage in a number of other ways, for
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example:
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1. Sierra Cart racing keeps a pointer in old stack
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2. Baldur's Gate *double* dereferences pointers in old stack
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3. NFL Blitz keeps it's linked lists on the stack and so simply calling
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an API causes corruption
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4. NFL Blitz 2000 runs out of stack space calling CreateFile
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5. Interplay EReg has uninitialized variables on the stack which are
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normally zeroed on win9x
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This shim is parameterized and takes a list of APIs and the behavior of
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each. Behavior is defined as the following:
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- No stack is used by this API
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0 - After API is called, old stack will be filled with zeroes
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1 - After API is called, old stack will be filled with valid pointers
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2 - After API is called, old stack will be filled with valid pointers
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to pointers
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The default is that no stack space is used by the API.
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Notes:
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This is a general purpose shim.
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History:
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05/03/2000 linstev Created
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03/12/2001 robkenny Blessed for DBCS
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02/07/2002 astritz Converted to strsafe
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--*/
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#include "precomp.h"
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IMPLEMENT_SHIM_BEGIN(StackSwap)
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#include "ShimHookMacro.h"
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#include "ShimStack.h"
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#include "StackSwap_Exports.h"
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#include "StackSwap_Excludes.h"
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APIHOOK_ENUM_BEGIN
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APIHOOK_ENUM_ENTRY(CreateThread)
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APIHOOK_ENUM_ENTRY(TerminateThread)
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APIHOOK_ENUM_ENTRY(ExitThread)
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APIHOOK_ENUM_END
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#define THREAD_VAR Vdm // The TEB variable to overwrite
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#define STUB_SIZE 64 // size of stub code in bytes
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#define STACK_SIZE 65536 // size of temporary stack
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#define STACK_COPY_SIZE 16 // number of dwords to copy from old stack
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#define STACK_FILL_SIZE 256 // default number of dwords to fill
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#define STACK_GUARD_SIZE 4096 // gaurd page at the top of the stack - must be a multiple of 4096
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#define STACK_FILL_NONE -1 // no old stack filling
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#define STACK_FILL_ZERO 0 // fill old stack with zeroes
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#define STACK_FILL_PTR1 1 // fill old stack with pointers
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#define STACK_FILL_PTR2 2 // fill old stack with pointers to pointers
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PVOID g_dwZero = 0; // used for pointer to zero
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PVOID g_dwPtr = &g_dwPtr; // used for pointer to pointer
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PVOID g_arrFill[] =
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{
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0,
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&g_dwZero,
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&g_dwPtr
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};
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// Store for each hook returned by the parser
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struct HOOK
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{
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char szModule[MAX_PATH]; // Module name
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char szFnName[MAX_PATH]; // Function name
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PVOID pfnNew; // Pointer to stub
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int dwFill; // Stack fill type
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DWORD dwFillSize; // Number of dwords to fill
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struct HOOK *next;
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};
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HOOK *g_pHooks = NULL;
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HOOK g_AllHooks[] =
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{
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{"KERNEL32.DLL", "*", NULL, STACK_FILL_NONE},
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{"GDI32.DLL", "*", NULL, STACK_FILL_NONE},
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{"USER32.DLL", "*", NULL, STACK_FILL_NONE},
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{"WINMM.DLL", "*", NULL, STACK_FILL_NONE}
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};
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DWORD dwStubCount = 0;
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// Thread local data
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typedef struct _THREAD_DATA
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{
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PVOID pfnHook; // Address of actual call
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PVOID pNewStack; // The new stack
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PVOID pOldStack; // The old stack
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DWORD dwFill; // Fill method
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DWORD dwFillSize; // Number of dwords to fill
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ULONG ulCount; // Number of times we've entered
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DWORD dwRet; // Return value
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DWORD dwEcx, dwEsi, dwEdi; // Tempory storage, since we don't have a stack
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} THREAD_DATA;
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/*++
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This function is called from the stubs. It's purpose is to give the API a new
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stack to use. It does this by doing the following:
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1. Copy the original stack to the new stack
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2. Call the original hook
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3. Copy the changed stack back to the original stack
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4. Return control to the original caller
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The only tricky things about this routine are that we don't want to use any
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stack at all (no push/pop) and we need to calculate how much stack was used
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for the parameters - something we don't know because we don't have the proto-
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type.
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If we really wanted to use push and pop, we could have set up a temporary
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stack, but since we only need ecx, esi and edi, there didn't seem to be any
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point.
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--*/
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__declspec(naked)
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void
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SwapStack()
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{
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__asm {
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inc [eax + THREAD_DATA.ulCount] // increment counter
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mov [eax + THREAD_DATA.dwEcx], ecx // backup ecx
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mov [eax + THREAD_DATA.dwEsi], esi // backup esi
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mov [eax + THREAD_DATA.dwEdi], edi // backup edi
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mov ecx, [esp] // retrieve 'Hook' from Stub()
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mov [eax + THREAD_DATA.pfnHook], ecx // which we got from the call
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add esp, 4 // move the stack up to the return address
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mov dword ptr [esp], offset SwapBack // fill in our new return address
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lea edi, [esp + 4] // dst = new stack
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mov esi, [eax + THREAD_DATA.pOldStack] // src = old stack
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add esi, 4 // note the +4s since the first dword is the return address
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cld // clear direction flag
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mov ecx, STACK_COPY_SIZE - 1 // copy off STACK_COPY_SIZE - 1 bytes
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rep movsd // do the copy
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mov ecx, [eax + THREAD_DATA.dwEcx] // restore ecx
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mov esi, [eax + THREAD_DATA.dwEsi] // restore esi
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mov edi, [eax + THREAD_DATA.dwEdi] // restore edi
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jmp [eax + THREAD_DATA.pfnHook] // jump back into the stub to do the actual
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SwapBack:
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mov [esp - 4], eax // unfortunately this is the only way to store the return
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mov eax, fs:[0x18] // get the TEB
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mov eax, [eax + TEB.THREAD_VAR] // get our thread local pointer
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mov [eax + THREAD_DATA.dwEcx], ecx // backup ecx
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mov [eax + THREAD_DATA.dwEsi], esi // backup esi
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mov [eax + THREAD_DATA.dwEdi], edi // backup edi
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mov ecx, [esp - 4] // get return value
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mov [eax + THREAD_DATA.dwRet], ecx // store return value for later
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mov ecx, esp // this is where we find out how many parameters were passed
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sub ecx, [eax + THREAD_DATA.pNewStack] // on the stack - so we get the difference in ecx
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mov edi, [eax + THREAD_DATA.pOldStack] // original stack
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mov esi, [edi] // read the real return address
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add edi, ecx // move the stack up, so we don't copy unnecessay stack
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mov [edi - 4], esi // put the return address into edi-4: this is the only time we
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// use app stack space at all
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mov esp, edi
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mov ecx, [eax + THREAD_DATA.dwFill] // test how we're going to fill
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cmp ecx, STACK_FILL_NONE
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jz FillDone
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mov esi, [ecx*4 + g_arrFill] // value to fill with
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lea edi, [esp - 8] // we're going to fill backwards, so esp-8 will skip the return address
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mov ecx, [eax + THREAD_DATA.dwFillSize] // number of dwords to fill with
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FillStack:
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mov [edi], esi // store the value
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sub edi, 4
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dec ecx
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jnz FillStack
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FillDone:
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mov ecx, [eax + THREAD_DATA.dwEcx] // restore ecx
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mov esi, [eax + THREAD_DATA.dwEsi] // restore esi
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mov edi, [eax + THREAD_DATA.dwEdi] // restore edi
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dec [eax + THREAD_DATA.ulCount] // decrement counter
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mov eax, [eax + THREAD_DATA.dwRet] // get the return value
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jmp dword ptr [esp - 4] // return to original caller
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}
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}
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//
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// We need the stub to do a far call to SwapStack since the stub will move, but
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// I can't seem to force the far call without this method
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//
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DWORD_PTR g_pfnStackSwap = (DWORD_PTR)SwapStack;
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/*++
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This is the stub function that is called by every API. It is copied from here
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to blocks of executable memory and the calls and fill types are written to
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hard coded addresses within it.
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The instuctions:
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mov [eax + THREAD_DATA.dwFill], 0xFFFFFFFF is replaced by
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mov [eax + THREAD_DATA.dwFill], FILL_TYPE
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mov [eax + THREAD_DATA.dwFillSize], 0xFFFFFFFF is replaced by
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mov [eax + THREAD_DATA.dwFill], FILL_SIZE
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and
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call g_pfnStackSwap is replaced by
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call g_pAPIHooks[api].pfnOld
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--*/
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__declspec(naked)
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void
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Stub()
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{
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__asm {
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mov eax, fs:[0x18] // get the TEB
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mov eax, [eax + TEB.THREAD_VAR] // get our thread local pointer
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or eax, eax // our pointer is gone
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jz Hook // exit gracefully
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cmp [eax + THREAD_DATA.ulCount], 0 // have we already swapped the stack
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jnz Hook
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mov [eax + THREAD_DATA.dwFill], 0xFFFFFFFF // the 0xFFFFFFFF will be replaced by the fill type
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mov [eax + THREAD_DATA.dwFillSize], 0xFFFFFFFF // the 0xFFFFFFFF will be replaced by the fill size
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mov [eax + THREAD_DATA.pOldStack], esp // backup the old stack
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mov esp, [eax + THREAD_DATA.pNewStack] // swap the stack
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call g_pfnStackSwap // call into the stack swapping code
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Hook:
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jmp [g_pHooks] // jump to the hook
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}
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}
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/*++
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Create a new stack
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--*/
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THREAD_DATA *
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AllocStack()
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{
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LPVOID p = VirtualAlloc(
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0,
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sizeof(THREAD_DATA) + STACK_SIZE + STACK_GUARD_SIZE,
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MEM_COMMIT,
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PAGE_READWRITE);
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if (p)
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{
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DWORD dwOld;
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if (!VirtualProtect(p, STACK_GUARD_SIZE, PAGE_READONLY | PAGE_GUARD, &dwOld))
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{
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DPFN( eDbgLevelError, "Failed to place Gaurd page at the top of the stack");
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}
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THREAD_DATA *pTD = (THREAD_DATA *)((DWORD_PTR)p + STACK_SIZE + STACK_GUARD_SIZE);
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pTD->pNewStack = (LPVOID)((DWORD_PTR)pTD - STACK_COPY_SIZE * 4);
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return pTD;
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}
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else
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{
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DPFN( eDbgLevelError, "Failed to allocate new stack");
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return NULL;
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}
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}
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/*++
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Free the stack
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--*/
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BOOL
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FreeStack(THREAD_DATA *pTD)
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{
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BOOL bRet = FALSE;
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if (pTD)
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{
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LPVOID p = (LPVOID)((DWORD_PTR)pTD - STACK_SIZE - STACK_GUARD_SIZE);
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bRet = VirtualFree(p, 0, MEM_RELEASE);
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}
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if (!bRet)
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{
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DPFN( eDbgLevelError, "Failed to free a stack");
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}
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return bRet;
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}
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/*++
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Hook CreateThread so we can add our stuff to the TEB.
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--*/
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HANDLE
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APIHOOK(CreateThread)(
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LPSECURITY_ATTRIBUTES lpThreadAttributes,
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DWORD dwStackSize,
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LPTHREAD_START_ROUTINE lpStartAddress,
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LPVOID lpParameter,
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DWORD dwCreationFlags,
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LPDWORD lpThreadId
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)
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{
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HANDLE hRet;
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DWORD dwFlags = dwCreationFlags;
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NEW_STACK();
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hRet = ORIGINAL_API(CreateThread)(
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lpThreadAttributes,
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dwStackSize,
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lpStartAddress,
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lpParameter,
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dwCreationFlags | CREATE_SUSPENDED,
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lpThreadId);
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if (hRet)
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{
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THREAD_BASIC_INFORMATION tbi;
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NTSTATUS Status;
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Status = NtQueryInformationThread(
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hRet,
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ThreadBasicInformation,
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&tbi,
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sizeof(tbi),
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NULL);
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if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
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{
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tbi.TebBaseAddress->THREAD_VAR = AllocStack();
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}
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if (!(dwFlags & CREATE_SUSPENDED))
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{
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ResumeThread(hRet);
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}
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}
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OLD_STACK();
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return hRet;
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}
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/*++
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Hook TerminateThread so we can clean up the thread local data.
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--*/
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BOOL
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APIHOOK(TerminateThread)(
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HANDLE hThread,
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DWORD dwExitCode
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)
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{
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THREAD_BASIC_INFORMATION tbi;
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NTSTATUS Status;
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BOOL bRet;
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THREAD_DATA *pTD = NULL;
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Status = NtQueryInformationThread(
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hThread,
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ThreadBasicInformation,
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&tbi,
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sizeof(tbi),
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NULL);
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if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
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{
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pTD = (THREAD_DATA *)(tbi.TebBaseAddress->THREAD_VAR);
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}
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bRet = ORIGINAL_API(TerminateThread)(hThread, dwExitCode);
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FreeStack(pTD);
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return bRet;
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}
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/*++
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Hook ExitThread so we can clean up the thread local data.
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--*/
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VOID
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APIHOOK(ExitThread)(
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DWORD dwExitCode
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)
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{
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NTSTATUS Status;
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THREAD_BASIC_INFORMATION tbi;
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HANDLE hThread = GetCurrentThread();
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Status = NtQueryInformationThread(
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hThread,
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ThreadBasicInformation,
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&tbi,
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sizeof(tbi),
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NULL);
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if ((NT_SUCCESS(Status)) && (tbi.TebBaseAddress))
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{
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THREAD_DATA *pTD = (THREAD_DATA *)tbi.TebBaseAddress->THREAD_VAR;
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// Make sure we don't free it if we're using it
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if (pTD && (pTD->ulCount == 0))
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{
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FreeStack(pTD);
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}
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}
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ORIGINAL_API(ExitThread)(dwExitCode);
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}
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/*++
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Add the specified hook to the linked list - this accepts wildcards.
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--*/
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VOID
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AddHooks(HOOK *pHook)
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{
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if (strstr(pHook->szFnName, "*") == 0)
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{
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// Now that we have a hook (not a wild card), we need to make sure it's
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// ok to add it to the list. There are some calls that cannot be shimmed
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for (int i=0; i<sizeof(Excludes)/sizeof(FNEXCLUDE); i++)
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{
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if ((_stricmp(pHook->szModule, (LPSTR)Excludes[i].pszModule) == 0) &&
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(strcmp(pHook->szFnName, (LPSTR)Excludes[i].pszFnName) == 0))
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{
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DPFN( eDbgLevelInfo,"Ignoring %s!%s", Excludes[i].pszModule, Excludes[i].pszFnName);
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return;
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}
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}
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// The hook passes, so add it to the list.
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HOOK *pH = (HOOK *) malloc(sizeof(HOOK));
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if (pH)
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{
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MoveMemory(pH, pHook, sizeof(HOOK));
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pH->next = g_pHooks;
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g_pHooks = pH;
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}
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return;
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}
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// Here we have to look through the exports
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LOADED_IMAGE image;
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if (!LoadModule(pHook->szModule, &image))
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{
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DPFN( eDbgLevelError, "Module %s not found", pHook->szModule);
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return;
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}
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EXPORT_ENUM exports;
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CHAR szFnName[MAX_PATH];
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if( StringCchCopyA(szFnName, MAX_PATH, pHook->szFnName) != S_OK )
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{
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DPFN(eDbgLevelError, "String Copy failed.");
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return;
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}
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DWORD dwLen = (DWORD)((DWORD_PTR)strstr(pHook->szFnName, "*") - (DWORD_PTR)&pHook->szFnName);
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// Enumerate the exports for this module
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BOOL bMore = EnumFirstExport(&image, &exports);
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while (bMore)
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{
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if ((dwLen == 0) ||
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(strncmp(exports.ExportFunction, szFnName, dwLen) == 0))
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{
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// We have a match
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if( StringCchCopyA(pHook->szFnName, MAX_PATH, exports.ExportFunction) != S_OK )
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{
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DPFN(eDbgLevelError, "String Copy failed.");
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return;
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}
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AddHooks(pHook);
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}
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bMore = EnumNextExport(&exports);
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}
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// Done with this module
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UnloadModule(&image);
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}
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/*++
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Parse the command line for APIs to fix stack problems with:
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USER32.DLL!GetDC:0; KERNEL32.DLL!CreateFile*
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The :X is to define behaviour - so:
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|
|
: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;
|
|
|
|
if( StringCchCopyA(szCommandLine, strlen(lpCommandLine) + 1, lpCommandLine) != S_OK )
|
|
{
|
|
DPFN(eDbgLevelError, "String Copy failed.");
|
|
goto Exit;
|
|
}
|
|
|
|
//
|
|
// 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));
|
|
if( StringCchCopyA(hook.szModule, MAX_PATH, token) != S_OK )
|
|
{
|
|
DPFN(eDbgLevelError, "String Copy failed.");
|
|
goto Exit;
|
|
}
|
|
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;
|
|
}
|
|
|
|
if( StringCchCopyA(hook.szFnName, MAX_PATH, token) != S_OK )
|
|
{
|
|
DPFN(eDbgLevelError, "String Copy failed.");
|
|
goto Exit;
|
|
}
|
|
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
|