diff options
| -rw-r--r-- | driver/memmod/memmod_windows.go | 84 | ||||
| -rw-r--r-- | go.mod | 2 |
2 files changed, 85 insertions, 1 deletions
diff --git a/driver/memmod/memmod_windows.go b/driver/memmod/memmod_windows.go index 075c03a0..6ced43fe 100644 --- a/driver/memmod/memmod_windows.go +++ b/driver/memmod/memmod_windows.go @@ -8,6 +8,8 @@ package memmod import ( "errors" "fmt" + "strings" + "sync" "syscall" "unsafe" @@ -382,6 +384,76 @@ func (module *Module) buildNameExports() error { return nil } +type addressRange struct { + start uintptr + end uintptr +} + +var loadedAddressRanges []addressRange +var loadedAddressRangesMu sync.RWMutex +var haveHookedRtlPcToFileHeader sync.Once +var hookRtlPcToFileHeaderResult error + +func hookRtlPcToFileHeader() error { + var kernelBase windows.Handle + err := windows.GetModuleHandleEx(windows.GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, windows.StringToUTF16Ptr("kernelbase.dll"), &kernelBase) + if err != nil { + return err + } + imageBase := unsafe.Pointer(kernelBase) + dosHeader := (*IMAGE_DOS_HEADER)(imageBase) + ntHeaders := (*IMAGE_NT_HEADERS)(unsafe.Add(imageBase, dosHeader.E_lfanew)) + importsDirectory := ntHeaders.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT] + importDescriptor := (*IMAGE_IMPORT_DESCRIPTOR)(unsafe.Add(imageBase, importsDirectory.VirtualAddress)) + for ; importDescriptor.Name != 0; importDescriptor = (*IMAGE_IMPORT_DESCRIPTOR)(unsafe.Add(unsafe.Pointer(importDescriptor), unsafe.Sizeof(*importDescriptor))) { + libraryName := windows.BytePtrToString((*byte)(unsafe.Add(imageBase, importDescriptor.Name))) + if strings.EqualFold(libraryName, "ntdll.dll") { + break + } + } + if importDescriptor.Name == 0 { + return errors.New("ntdll.dll not found") + } + originalThunk := (*uintptr)(unsafe.Add(imageBase, importDescriptor.OriginalFirstThunk())) + thunk := (*uintptr)(unsafe.Add(imageBase, importDescriptor.FirstThunk)) + for ; *originalThunk != 0; originalThunk = (*uintptr)(unsafe.Add(unsafe.Pointer(originalThunk), unsafe.Sizeof(*originalThunk))) { + if *originalThunk&IMAGE_ORDINAL_FLAG == 0 { + function := (*IMAGE_IMPORT_BY_NAME)(unsafe.Add(imageBase, *originalThunk)) + name := windows.BytePtrToString(&function.Name[0]) + if name == "RtlPcToFileHeader" { + break + } + } + thunk = (*uintptr)(unsafe.Add(unsafe.Pointer(thunk), unsafe.Sizeof(*thunk))) + } + if *originalThunk == 0 { + return errors.New("RtlPcToFileHeader not found") + } + var oldProtect uint32 + err = windows.VirtualProtect(uintptr(unsafe.Pointer(thunk)), unsafe.Sizeof(*thunk), windows.PAGE_READWRITE, &oldProtect) + if err != nil { + return err + } + originalRtlPcToFileHeader := *thunk + *thunk = windows.NewCallback(func(pcValue uintptr, baseOfImage *uintptr) uintptr { + loadedAddressRangesMu.RLock() + for i := range loadedAddressRanges { + if pcValue >= loadedAddressRanges[i].start && pcValue < loadedAddressRanges[i].end { + pcValue = *thunk + break + } + } + loadedAddressRangesMu.RUnlock() + ret, _, _ := syscall.Syscall(originalRtlPcToFileHeader, 2, pcValue, uintptr(unsafe.Pointer(baseOfImage)), 0) + return ret + }) + err = windows.VirtualProtect(uintptr(unsafe.Pointer(thunk)), unsafe.Sizeof(*thunk), oldProtect, &oldProtect) + if err != nil { + return err + } + return nil +} + // LoadLibrary loads module image to memory. func LoadLibrary(data []byte) (module *Module, err error) { addr := uintptr(unsafe.Pointer(&data[0])) @@ -513,6 +585,18 @@ func LoadLibrary(data []byte) (module *Module, err error) { // Register exception tables, if they exist. module.registerExceptionHandlers() + // Register function PCs. + loadedAddressRangesMu.Lock() + loadedAddressRanges = append(loadedAddressRanges, addressRange{module.codeBase, module.codeBase + alignedImageSize}) + loadedAddressRangesMu.Unlock() + haveHookedRtlPcToFileHeader.Do(func() { + hookRtlPcToFileHeaderResult = hookRtlPcToFileHeader() + }) + err = hookRtlPcToFileHeaderResult + if err != nil { + return + } + // TLS callbacks are executed BEFORE the main loading. module.executeTLS() @@ -1,6 +1,6 @@ module golang.zx2c4.com/wireguard/windows -go 1.16 +go 1.17 require ( github.com/lxn/walk v0.0.0-20210112085537-c389da54e794 |