Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "PoisonIOInterposer.h"
#include <algorithm>
#include <stdio.h>
#include <vector>
#include <io.h>
#include <windows.h>
#include <winternl.h>
#include "mozilla/Assertions.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/FileUtilsWin.h"
#include "mozilla/IOInterposer.h"
#include "mozilla/Mutex.h"
#include "mozilla/NativeNt.h"
#include "mozilla/SmallArrayLRUCache.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/UniquePtr.h"
#include "nsTArray.h"
#include "nsWindowsDllInterceptor.h"
#ifdef MOZ_REPLACE_MALLOC
# include "replace_malloc_bridge.h"
#endif
namespace {
// Keep track of poisoned state. Notice that there is no reason to lock access
// to this variable as it's only changed in InitPoisonIOInterposer and
// ClearPoisonIOInterposer which may only be called on the main-thread when no
// other threads are running.
static bool sIOPoisoned = false;
/************************ Internal NT API Declarations ************************/
/*
* Function pointer declaration for internal NT routine to create/open files.
* For documentation on the NtCreateFile routine, see MSDN.
*/
typedef NTSTATUS(NTAPI* NtCreateFileFn)(
PHANDLE aFileHandle, ACCESS_MASK aDesiredAccess,
POBJECT_ATTRIBUTES aObjectAttributes, PIO_STATUS_BLOCK aIoStatusBlock,
PLARGE_INTEGER aAllocationSize, ULONG aFileAttributes, ULONG aShareAccess,
ULONG aCreateDisposition, ULONG aCreateOptions, PVOID aEaBuffer,
ULONG aEaLength);
/**
* Function pointer declaration for internal NT routine to read data from file.
* For documentation on the NtReadFile routine, see ZwReadFile on MSDN.
*/
typedef NTSTATUS(NTAPI* NtReadFileFn)(HANDLE aFileHandle, HANDLE aEvent,
PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus, PVOID aBuffer,
ULONG aLength, PLARGE_INTEGER aOffset,
PULONG aKey);
/**
* Function pointer declaration for internal NT routine to read data from file.
* No documentation exists, see wine sources for details.
*/
typedef NTSTATUS(NTAPI* NtReadFileScatterFn)(
HANDLE aFileHandle, HANDLE aEvent, PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus, FILE_SEGMENT_ELEMENT* aSegments, ULONG aLength,
PLARGE_INTEGER aOffset, PULONG aKey);
/**
* Function pointer declaration for internal NT routine to write data to file.
* For documentation on the NtWriteFile routine, see ZwWriteFile on MSDN.
*/
typedef NTSTATUS(NTAPI* NtWriteFileFn)(HANDLE aFileHandle, HANDLE aEvent,
PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus,
PVOID aBuffer, ULONG aLength,
PLARGE_INTEGER aOffset, PULONG aKey);
/**
* Function pointer declaration for internal NT routine to write data to file.
* No documentation exists, see wine sources for details.
*/
typedef NTSTATUS(NTAPI* NtWriteFileGatherFn)(
HANDLE aFileHandle, HANDLE aEvent, PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus, FILE_SEGMENT_ELEMENT* aSegments, ULONG aLength,
PLARGE_INTEGER aOffset, PULONG aKey);
/**
* Function pointer declaration for internal NT routine to flush to disk.
* For documentation on the NtFlushBuffersFile routine, see ZwFlushBuffersFile
* on MSDN.
*/
typedef NTSTATUS(NTAPI* NtFlushBuffersFileFn)(HANDLE aFileHandle,
PIO_STATUS_BLOCK aIoStatusBlock);
typedef struct _FILE_NETWORK_OPEN_INFORMATION* PFILE_NETWORK_OPEN_INFORMATION;
/**
* Function pointer delaration for internal NT routine to query file attributes.
* (equivalent to stat)
*/
typedef NTSTATUS(NTAPI* NtQueryFullAttributesFileFn)(
POBJECT_ATTRIBUTES aObjectAttributes,
PFILE_NETWORK_OPEN_INFORMATION aFileInformation);
/*************************** Auxiliary Declarations ***************************/
// Cache of filenames associated with handles.
// `static` to be shared between all calls to `Filename()`.
// This assumes handles are not reused, at least within a windows of 32
// handles.
// Profiling showed that during startup, around half of `Filename()` calls are
// resolved with the first entry (best case), and 32 entries cover >95% of
// cases, reducing the average `Filename()` cost by 5-10x.
using HandleToFilenameCache = mozilla::SmallArrayLRUCache<HANDLE, nsString, 32>;
static mozilla::UniquePtr<HandleToFilenameCache> sHandleToFilenameCache;
/**
* RAII class for timing the duration of an I/O call and reporting the result
* to the mozilla::IOInterposeObserver API.
*/
class WinIOAutoObservation : public mozilla::IOInterposeObserver::Observation {
public:
WinIOAutoObservation(mozilla::IOInterposeObserver::Operation aOp,
HANDLE aFileHandle, const LARGE_INTEGER* aOffset)
: mozilla::IOInterposeObserver::Observation(
aOp, sReference, !mozilla::IsDebugFile(aFileHandle)),
mFileHandle(aFileHandle),
mFileHandleType(GetFileType(aFileHandle)),
mHasQueriedFilename(false) {
if (mShouldReport) {
mOffset.QuadPart = aOffset ? aOffset->QuadPart : 0;
}
}
WinIOAutoObservation(mozilla::IOInterposeObserver::Operation aOp,
nsAString& aFilename)
: mozilla::IOInterposeObserver::Observation(aOp, sReference),
mFileHandle(nullptr),
mFileHandleType(FILE_TYPE_UNKNOWN),
mHasQueriedFilename(false) {
if (mShouldReport) {
nsAutoString dosPath;
if (mozilla::NtPathToDosPath(aFilename, dosPath)) {
mFilename = dosPath;
} else {
// If we can't get a dosPath, what we have is better than nothing.
mFilename = aFilename;
}
mHasQueriedFilename = true;
mOffset.QuadPart = 0;
}
}
void SetHandle(HANDLE aFileHandle) {
mFileHandle = aFileHandle;
if (aFileHandle) {
// Note: `GetFileType()` is fast enough that we don't need to cache it.
mFileHandleType = GetFileType(aFileHandle);
if (mHasQueriedFilename) {
// `mHasQueriedFilename` indicates we already have a filename, add it to
// the cache with the now-known handle.
sHandleToFilenameCache->Add(aFileHandle, mFilename);
}
}
}
const char* FileType() const override;
void Filename(nsAString& aFilename) override;
~WinIOAutoObservation() { Report(); }
private:
HANDLE mFileHandle;
DWORD mFileHandleType;
LARGE_INTEGER mOffset;
bool mHasQueriedFilename;
nsString mFilename;
static const char* sReference;
};
const char* WinIOAutoObservation::sReference = "PoisonIOInterposer";
// Get filename for this observation
void WinIOAutoObservation::Filename(nsAString& aFilename) {
// If mHasQueriedFilename is true, then filename is already stored in
// mFilename
if (mHasQueriedFilename) {
aFilename = mFilename;
return;
}
if (mFileHandle) {
mFilename = sHandleToFilenameCache->FetchOrAdd(mFileHandle, [&]() {
nsString filename;
if (!mozilla::HandleToFilename(mFileHandle, mOffset, filename)) {
// HandleToFilename could fail (return false) but still have added
// something to `filename`, so it should be cleared in this case.
filename.Truncate();
}
return filename;
});
}
mHasQueriedFilename = true;
aFilename = mFilename;
}
const char* WinIOAutoObservation::FileType() const {
if (mFileHandle) {
switch (mFileHandleType) {
case FILE_TYPE_CHAR:
return "Char";
case FILE_TYPE_DISK:
return "File";
case FILE_TYPE_PIPE:
return "Pipe";
case FILE_TYPE_REMOTE:
return "Remote";
case FILE_TYPE_UNKNOWN:
default:
break;
}
}
// Fallback to base class default implementation.
return mozilla::IOInterposeObserver::Observation::FileType();
}
/*************************** IO Interposing Methods ***************************/
// Function pointers to original functions
static mozilla::WindowsDllInterceptor::FuncHookType<NtCreateFileFn>
gOriginalNtCreateFile;
static mozilla::WindowsDllInterceptor::FuncHookType<NtReadFileFn>
gOriginalNtReadFile;
static mozilla::WindowsDllInterceptor::FuncHookType<NtReadFileScatterFn>
gOriginalNtReadFileScatter;
static mozilla::WindowsDllInterceptor::FuncHookType<NtWriteFileFn>
gOriginalNtWriteFile;
static mozilla::WindowsDllInterceptor::FuncHookType<NtWriteFileGatherFn>
gOriginalNtWriteFileGather;
static mozilla::WindowsDllInterceptor::FuncHookType<NtFlushBuffersFileFn>
gOriginalNtFlushBuffersFile;
static mozilla::WindowsDllInterceptor::FuncHookType<NtQueryFullAttributesFileFn>
gOriginalNtQueryFullAttributesFile;
static NTSTATUS NTAPI InterposedNtCreateFile(
PHANDLE aFileHandle, ACCESS_MASK aDesiredAccess,
POBJECT_ATTRIBUTES aObjectAttributes, PIO_STATUS_BLOCK aIoStatusBlock,
PLARGE_INTEGER aAllocationSize, ULONG aFileAttributes, ULONG aShareAccess,
ULONG aCreateDisposition, ULONG aCreateOptions, PVOID aEaBuffer,
ULONG aEaLength) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtCreateFile);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtCreateFile(
aFileHandle, aDesiredAccess, aObjectAttributes, aIoStatusBlock,
aAllocationSize, aFileAttributes, aShareAccess, aCreateDisposition,
aCreateOptions, aEaBuffer, aEaLength);
}
// Report IO
const wchar_t* buf =
aObjectAttributes ? aObjectAttributes->ObjectName->Buffer : L"";
uint32_t len = aObjectAttributes
? aObjectAttributes->ObjectName->Length / sizeof(WCHAR)
: 0;
nsDependentSubstring filename(buf, len);
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpCreateOrOpen,
filename);
// Execute original function
NTSTATUS status = gOriginalNtCreateFile(
aFileHandle, aDesiredAccess, aObjectAttributes, aIoStatusBlock,
aAllocationSize, aFileAttributes, aShareAccess, aCreateDisposition,
aCreateOptions, aEaBuffer, aEaLength);
if (NT_SUCCESS(status) && aFileHandle) {
timer.SetHandle(*aFileHandle);
}
return status;
}
static NTSTATUS NTAPI InterposedNtReadFile(HANDLE aFileHandle, HANDLE aEvent,
PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus,
PVOID aBuffer, ULONG aLength,
PLARGE_INTEGER aOffset,
PULONG aKey) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtReadFile);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtReadFile(aFileHandle, aEvent, aApc, aApcCtx, aIoStatus,
aBuffer, aLength, aOffset, aKey);
}
// Report IO
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpRead, aFileHandle,
aOffset);
// Execute original function
return gOriginalNtReadFile(aFileHandle, aEvent, aApc, aApcCtx, aIoStatus,
aBuffer, aLength, aOffset, aKey);
}
static NTSTATUS NTAPI InterposedNtReadFileScatter(
HANDLE aFileHandle, HANDLE aEvent, PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus, FILE_SEGMENT_ELEMENT* aSegments, ULONG aLength,
PLARGE_INTEGER aOffset, PULONG aKey) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtReadFileScatter);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtReadFileScatter(aFileHandle, aEvent, aApc, aApcCtx,
aIoStatus, aSegments, aLength, aOffset,
aKey);
}
// Report IO
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpRead, aFileHandle,
aOffset);
// Execute original function
return gOriginalNtReadFileScatter(aFileHandle, aEvent, aApc, aApcCtx,
aIoStatus, aSegments, aLength, aOffset,
aKey);
}
// Interposed NtWriteFile function
static NTSTATUS NTAPI InterposedNtWriteFile(HANDLE aFileHandle, HANDLE aEvent,
PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus,
PVOID aBuffer, ULONG aLength,
PLARGE_INTEGER aOffset,
PULONG aKey) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtWriteFile);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtWriteFile(aFileHandle, aEvent, aApc, aApcCtx, aIoStatus,
aBuffer, aLength, aOffset, aKey);
}
// Report IO
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpWrite, aFileHandle,
aOffset);
// Execute original function
return gOriginalNtWriteFile(aFileHandle, aEvent, aApc, aApcCtx, aIoStatus,
aBuffer, aLength, aOffset, aKey);
}
// Interposed NtWriteFileGather function
static NTSTATUS NTAPI InterposedNtWriteFileGather(
HANDLE aFileHandle, HANDLE aEvent, PIO_APC_ROUTINE aApc, PVOID aApcCtx,
PIO_STATUS_BLOCK aIoStatus, FILE_SEGMENT_ELEMENT* aSegments, ULONG aLength,
PLARGE_INTEGER aOffset, PULONG aKey) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtWriteFileGather);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtWriteFileGather(aFileHandle, aEvent, aApc, aApcCtx,
aIoStatus, aSegments, aLength, aOffset,
aKey);
}
// Report IO
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpWrite, aFileHandle,
aOffset);
// Execute original function
return gOriginalNtWriteFileGather(aFileHandle, aEvent, aApc, aApcCtx,
aIoStatus, aSegments, aLength, aOffset,
aKey);
}
static NTSTATUS NTAPI InterposedNtFlushBuffersFile(
HANDLE aFileHandle, PIO_STATUS_BLOCK aIoStatusBlock) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtFlushBuffersFile);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtFlushBuffersFile(aFileHandle, aIoStatusBlock);
}
// Report IO
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpFSync, aFileHandle,
nullptr);
// Execute original function
return gOriginalNtFlushBuffersFile(aFileHandle, aIoStatusBlock);
}
static NTSTATUS NTAPI InterposedNtQueryFullAttributesFile(
POBJECT_ATTRIBUTES aObjectAttributes,
PFILE_NETWORK_OPEN_INFORMATION aFileInformation) {
// Something is badly wrong if this function is undefined
MOZ_ASSERT(gOriginalNtQueryFullAttributesFile);
if (!mozilla::nt::RtlGetThreadLocalStoragePointer()) {
return gOriginalNtQueryFullAttributesFile(aObjectAttributes,
aFileInformation);
}
// Report IO
const wchar_t* buf =
aObjectAttributes ? aObjectAttributes->ObjectName->Buffer : L"";
uint32_t len = aObjectAttributes
? aObjectAttributes->ObjectName->Length / sizeof(WCHAR)
: 0;
nsDependentSubstring filename(buf, len);
WinIOAutoObservation timer(mozilla::IOInterposeObserver::OpStat, filename);
// Execute original function
return gOriginalNtQueryFullAttributesFile(aObjectAttributes,
aFileInformation);
}
} // namespace
/******************************** IO Poisoning ********************************/
// Windows DLL interceptor
static mozilla::WindowsDllInterceptor sNtDllInterceptor;
namespace mozilla {
void InitPoisonIOInterposer() {
// Currently we hook the functions not early enough to precede third-party
// injections. Until we implement a compatible way e.g. applying a hook
// the known condition(s).
// simultaneously when we're applying a hook on NtReadFile.
// overwriting part of ours in an incompatible way.
if (::GetModuleHandleW(L"kwsui64.dll") || ::GetModuleHandleW(L"ffm64.dll")) {
return;
}
// Don't poison twice... as this function may only be invoked on the main
// thread when no other threads are running, it safe to allow multiple calls
// to InitPoisonIOInterposer() without complaining (ie. failing assertions).
if (sIOPoisoned) {
return;
}
sIOPoisoned = true;
MOZ_RELEASE_ASSERT(!sHandleToFilenameCache);
sHandleToFilenameCache = mozilla::MakeUnique<HandleToFilenameCache>();
mozilla::RunOnShutdown([]() {
// The interposer may still be active after the final shutdown phase
// (especially since ClearPoisonIOInterposer() is never called, see bug
// 1647107), so we cannot just reset the pointer. Instead we put the cache
// in shutdown mode, to clear its memory and stop caching operations.
sHandleToFilenameCache->Shutdown();
});
// Stdout and Stderr are OK.
MozillaRegisterDebugFD(1);
if (::GetStdHandle(STD_OUTPUT_HANDLE) != ::GetStdHandle(STD_ERROR_HANDLE)) {
MozillaRegisterDebugFD(2);
}
#ifdef MOZ_REPLACE_MALLOC
// The contract with InitDebugFd is that the given registry can be used
// at any moment, so the instance needs to persist longer than the scope
// of this functions.
static DebugFdRegistry registry;
ReplaceMalloc::InitDebugFd(registry);
#endif
// Initialize dll interceptor and add hooks
sNtDllInterceptor.Init("ntdll.dll");
gOriginalNtCreateFile.Set(sNtDllInterceptor, "NtCreateFile",
&InterposedNtCreateFile);
gOriginalNtReadFile.Set(sNtDllInterceptor, "NtReadFile",
&InterposedNtReadFile);
gOriginalNtReadFileScatter.Set(sNtDllInterceptor, "NtReadFileScatter",
&InterposedNtReadFileScatter);
gOriginalNtWriteFile.Set(sNtDllInterceptor, "NtWriteFile",
&InterposedNtWriteFile);
gOriginalNtWriteFileGather.Set(sNtDllInterceptor, "NtWriteFileGather",
&InterposedNtWriteFileGather);
gOriginalNtFlushBuffersFile.Set(sNtDllInterceptor, "NtFlushBuffersFile",
&InterposedNtFlushBuffersFile);
gOriginalNtQueryFullAttributesFile.Set(sNtDllInterceptor,
"NtQueryFullAttributesFile",
&InterposedNtQueryFullAttributesFile);
}
void ClearPoisonIOInterposer() {
if (sIOPoisoned) {
// Destroy the DLL interceptor
sIOPoisoned = false;
sNtDllInterceptor.Clear();
sHandleToFilenameCache->Clear();
}
}
} // namespace mozilla