NTSTATUS MExcept::CreateVEH(size_t pTargetBase, size_t imageSize, eModType mt, bool partial) {
AsmJitHelper a;
uint64_t result = 0;
auto& mods = _proc.Modules();
#ifdef USE64
// Add module to module table
if(!_pModTable.Valid()) {
_pModTable = _proc.Memory().Allocate(0x1000);
_pModTable.Release();
if(!_pModTable.Valid())
return LastNtStatus();
}
ModuleTable table;
_pModTable.Read(0, table);
// Add new entry to the table
table.entry[table.count].base = pTargetBase;
table.entry[table.count].size = imageSize;
table.count++;
_pModTable.Write(0, table);
// No handler required
if(partial)
return STATUS_SUCCESS;
// VEH codecave
_pVEHCode = _proc.Memory().Allocate(0x2000);
_pVEHCode.Release();
if(!_pVEHCode.Valid())
return LastNtStatus();
BLACBONE_TRACE("ManualMap: Vectored hander: 0x%p\n", _pVEHCode.Ptr());
asmjit::Label lExit = a->newLabel();
asmjit::Label lLoop1 = a->newLabel();
asmjit::Label skip1 = a->newLabel();
asmjit::Label found1 = a->newLabel();
//
// Assembly code for VectoredHandler64
// 0x10 - EXCEPTION_RECORD.ExceptionAddress
// 0x20 - EXCEPTION_RECORD.ExceptionInformation[0]
// 0x30 - EXCEPTION_RECORD.ExceptionInformation[2]
// 0x38 - EXCEPTION_RECORD.ExceptionInformation[3]
//
a->mov(asmjit::host::rax, asmjit::host::qword_ptr(asmjit::host::rcx));
a->cmp(asmjit::host::dword_ptr(asmjit::host::rax), EH_EXCEPTION_NUMBER); // Exception code
a->jne(lExit);
a->cmp(asmjit::host::qword_ptr(asmjit::host::rax, 0x20), EH_PURE_MAGIC_NUMBER1); // Sub code
a->jne(lExit);
a->cmp(asmjit::host::qword_ptr(asmjit::host::rax, 0x38), 0); // Image base
a->jne(lExit);
a->mov(asmjit::host::r9, _pModTable.Ptr());
a->mov(asmjit::host::rdx, asmjit::host::qword_ptr(asmjit::host::r9)); // Record count
a->add(asmjit::host::r9, sizeof(table.count));
a->xor_(asmjit::host::r10, asmjit::host::r10);
a->bind(lLoop1);
a->mov(asmjit::host::r8, asmjit::host::qword_ptr(asmjit::host::rax, 0x30));
a->mov(asmjit::host::r11, asmjit::host::qword_ptr(asmjit::host::r9));
a->cmp(asmjit::host::r8, asmjit::host::r11);
a->jl(skip1);
a->add(asmjit::host::r11, asmjit::host::qword_ptr(asmjit::host::r9, sizeof(table.entry[0].base))); // Size
a->cmp(asmjit::host::r8, asmjit::host::r11);
a->jg(skip1);
a->jmp(found1);
a->bind(skip1);
a->add(asmjit::host::r9, sizeof(ExceptionModule));
a->add(asmjit::host::r10, 1);
a->cmp(asmjit::host::r10, asmjit::host::rdx);
a->jne(lLoop1);
a->jmp(lExit);
a->bind(found1);
a->mov(asmjit::host::qword_ptr(asmjit::host::rax, 0x20), EH_MAGIC_NUMBER1);
a->mov(asmjit::host::rcx, asmjit::host::qword_ptr(asmjit::host::rcx));
a->mov(asmjit::host::rdx, asmjit::host::qword_ptr(asmjit::host::r9));
a->mov(asmjit::host::qword_ptr(asmjit::host::rax, 0x38), asmjit::host::rdx);
a->bind(lExit);
a->xor_(asmjit::host::rax, asmjit::host::rax);
a->ret();
a->db(0xCC);
a->db(0xCC);
a->db(0xCC);
if(_pVEHCode.Write(0, a->getCodeSize(), a->make()) != STATUS_SUCCESS) {
_pVEHCode.Free();
return LastNtStatus();
}
#else
UNREFERENCED_PARAMETER(pTargetBase);
UNREFERENCED_PARAMETER(imageSize);
// No handler required
if(partial)
return STATUS_SUCCESS;
// VEH codecave
_pVEHCode = _proc.Memory().Allocate(0x2000);
_pVEHCode.Release();
if(!_pVEHCode.Valid())
return LastNtStatus();
// Resolve compiler incremental table address, if any
void *pFunc = ResolveJmp(&VectoredHandler);
size_t fnSize = static_cast<size_t>(SizeOfProc(pFunc));
size_t dataOfs = 0, code_ofs = 0, code_ofs2 = 0;;
// Find and replace magic values
for(uint8_t *pData = reinterpret_cast<uint8_t*>(pFunc);
pData < reinterpret_cast<uint8_t*>(pFunc) + fnSize - 4;
pData++) {
// LdrpInvertedFunctionTable
if(*(size_t*)pData == 0xDEADDA7A) {
dataOfs = pData - reinterpret_cast<uint8_t*>(pFunc);
continue;
}
// DecodeSystemPointer address
if(*(size_t*)pData == 0xDEADC0DE) {
code_ofs = pData - reinterpret_cast<uint8_t*>(pFunc);
break;
}
// LdrProtectMrdata address
if(*(size_t*)pData == 0xDEADC0D2) {
code_ofs2 = pData - reinterpret_cast<uint8_t*>(pFunc);
continue;
}
}
auto pDecode = mods.GetExport(mods.GetModule(L"ntdll.dll", Sections, mt), "RtlDecodeSystemPointer").procAddress;
// Write handler data into target process
if(!NT_SUCCESS(_pVEHCode.Write(0, fnSize, pFunc)) ||
!NT_SUCCESS(_pVEHCode.Write(dataOfs, _proc.NativeLdr().LdrpInvertedFunctionTable())) ||
!NT_SUCCESS(_pVEHCode.Write(code_ofs, static_cast<size_t>(pDecode))) ||
!NT_SUCCESS(_pVEHCode.Write(code_ofs2, _proc.NativeLdr().LdrProtectMrdata()))) {
_pVEHCode.Free();
return LastNtStatus();
}
#endif
// AddVectoredExceptionHandler(0, pHandler);
auto pAddHandler = mods.GetExport(mods.GetModule(L"ntdll.dll", Sections, mt), "RtlAddVectoredExceptionHandler").procAddress;
if(pAddHandler == 0)
return STATUS_NOT_FOUND;
a->reset();
a.GenPrologue();
a.GenCall(static_cast<size_t>(pAddHandler), {0, _pVEHCode.Ptr<size_t>()});
_proc.Remote().AddReturnWithEvent(a, mt);
a.GenEpilogue();
_proc.Remote().ExecInWorkerThread(a->make(), a->getCodeSize(), result);
_hVEH = static_cast<size_t>(result);
return (_hVEH == 0 ? STATUS_NOT_FOUND : STATUS_SUCCESS);
}
/// <summary>
/// Inject VEH wrapper into process
/// Used to enable execution of SEH handlers out of image
/// </summary>
/// <param name="pTargetBase">Target image base address</param>
/// <param name="imageSize">Size of the image</param>
/// <returns>Error code</returns>
NTSTATUS MExcept::CreateVEH( size_t pTargetBase, size_t imageSize )
{
AsmJitHelper ea;
uint64_t result = 0;
// VEH codecave
_pVEHCode = _proc.memory().Allocate( 0x2000 );
_pVEHCode.Release();
if (!_pVEHCode.valid())
return LastNtStatus();
#ifdef USE64
asmjit::Label lExit = ea->newLabel();
//
// Assembly code for VectoredHandler64
// 0x10 - EXCEPTION_RECORD.ExceptionAddress
// 0x20 - EXCEPTION_RECORD.ExceptionInformation[0]
// 0x30 - EXCEPTION_RECORD.ExceptionInformation[2]
// 0x38 - EXCEPTION_RECORD.ExceptionInformation[3]
//
ea->mov( asmjit::host::rax, qword_ptr( asmjit::host::rcx ) );
ea->cmp( asmjit::host::dword_ptr( asmjit::host::rax ), EH_EXCEPTION_NUMBER );
ea->jne( lExit );
ea->mov( asmjit::host::rdx, pTargetBase );
ea->mov( asmjit::host::r8, asmjit::host::qword_ptr( asmjit::host::rax, 0x30 ) );
ea->cmp( asmjit::host::r8, asmjit::host::rdx );;
ea->jl( lExit );
ea->add( asmjit::host::rdx, imageSize );
ea->cmp( asmjit::host::r8, asmjit::host::rdx );;
ea->jg( lExit );
ea->cmp( asmjit::host::qword_ptr( asmjit::host::rax, 0x20 ), EH_PURE_MAGIC_NUMBER1 );;
ea->jne( lExit );
ea->cmp( asmjit::host::qword_ptr( asmjit::host::rax, 0x38 ), 0 );
ea->jne( lExit );
ea->mov( asmjit::host::qword_ptr( asmjit::host::rax, 0x20 ), EH_MAGIC_NUMBER1 );
ea->mov( asmjit::host::rcx, qword_ptr( asmjit::host::rcx ) );
ea->mov( asmjit::host::rdx, pTargetBase );
ea->mov( asmjit::host::qword_ptr( asmjit::host::rax, 0x38 ), asmjit::host::rdx );
ea->bind( lExit );
ea->xor_( asmjit::host::rax, asmjit::host::rax );
ea->ret();
ea->emit( 0xCC );
ea->emit( 0xCC );
ea->emit( 0xCC );
if (_pVEHCode.Write( 0, ea->getCodeSize(), ea->make() ) != STATUS_SUCCESS)
{
_pVEHCode.Free();
return LastNtStatus();
}
#else
UNREFERENCED_PARAMETER( pTargetBase );
UNREFERENCED_PARAMETER( imageSize );
// Resolve compiler incremental table address if any
void *pFunc = ResolveJmp( &VectoredHandler );
size_t fnSize = static_cast<size_t>(SizeOfProc( pFunc ));
size_t dataOfs = 0, code_ofs = 0;
// Find and replace magic values
for (uint8_t *pData = reinterpret_cast<uint8_t*>(pFunc);
pData < reinterpret_cast<uint8_t*>(pFunc) + fnSize - 4;
pData++)
{
// LdrpInvertedFunctionTable
if(*(size_t*)pData == 0xDEADDA7A)
{
dataOfs = pData - reinterpret_cast<uint8_t*>(pFunc);
continue;
}
// DecodeSystemPointer address
if(*(size_t*)pData == 0xDEADC0DE)
{
code_ofs = pData - reinterpret_cast<uint8_t*>(pFunc);
break;
}
}
// Write handler data into target process
if (_pVEHCode.Write( 0, fnSize, pFunc ) != STATUS_SUCCESS ||
_pVEHCode.Write( dataOfs, _proc.nativeLdr().LdrpInvertedFunctionTable() ) != STATUS_SUCCESS ||
_pVEHCode.Write( code_ofs, &DecodeSystemPointer ) != STATUS_SUCCESS)
{
_pVEHCode.Free();
return LastNtStatus();
}
#endif
ea.GenPrologue();
// AddVectoredExceptionHandler(0, pHandler);
ea.GenCall( reinterpret_cast<void*>(&AddVectoredExceptionHandler), { 0, _pVEHCode.ptr<size_t>() } );
_proc.remote().AddReturnWithEvent( ea );
ea.GenEpilogue();
_proc.remote().ExecInWorkerThread( ea->make(), ea->getCodeSize(), result );
_hVEH = static_cast<size_t>(result);
return (result == 0 ? STATUS_NOT_FOUND : STATUS_SUCCESS);
}