mozjs68/mozglue/misc/NativeNt.h

751 lines
22 KiB
C++

/* -*- 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
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
#ifndef mozilla_NativeNt_h
#define mozilla_NativeNt_h
#include <stdint.h>
#include <windows.h>
#include <winnt.h>
#include <winternl.h>
#include <algorithm>
#include "mozilla/ArrayUtils.h"
#include "mozilla/Attributes.h"
#include "mozilla/LauncherResult.h"
#include "mozilla/Maybe.h"
#include "mozilla/Span.h"
// The declarations within this #if block are intended to be used for initial
// process initialization ONLY. You probably don't want to be using these in
// normal Gecko code!
#if !defined(MOZILLA_INTERNAL_API)
extern "C" {
# if !defined(STATUS_ACCESS_DENIED)
# define STATUS_ACCESS_DENIED ((NTSTATUS)0xC0000022L)
# endif // !defined(STATUS_ACCESS_DENIED)
# if !defined(STATUS_DLL_NOT_FOUND)
# define STATUS_DLL_NOT_FOUND ((NTSTATUS)0xC0000135L)
# endif // !defined(STATUS_DLL_NOT_FOUND)
enum SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 };
NTSTATUS NTAPI NtMapViewOfSection(
HANDLE aSection, HANDLE aProcess, PVOID* aBaseAddress, ULONG_PTR aZeroBits,
SIZE_T aCommitSize, PLARGE_INTEGER aSectionOffset, PSIZE_T aViewSize,
SECTION_INHERIT aInheritDisposition, ULONG aAllocationType,
ULONG aProtectionFlags);
NTSTATUS NTAPI NtUnmapViewOfSection(HANDLE aProcess, PVOID aBaseAddress);
enum MEMORY_INFORMATION_CLASS {
MemoryBasicInformation = 0,
MemorySectionName = 2
};
// NB: When allocating, space for the buffer must also be included
typedef struct _MEMORY_SECTION_NAME {
UNICODE_STRING mSectionFileName;
} MEMORY_SECTION_NAME, *PMEMORY_SECTION_NAME;
NTSTATUS NTAPI NtQueryVirtualMemory(HANDLE aProcess, PVOID aBaseAddress,
MEMORY_INFORMATION_CLASS aMemInfoClass,
PVOID aMemInfo, SIZE_T aMemInfoLen,
PSIZE_T aReturnLen);
LONG NTAPI RtlCompareUnicodeString(PCUNICODE_STRING aStr1,
PCUNICODE_STRING aStr2,
BOOLEAN aCaseInsensitive);
BOOLEAN NTAPI RtlEqualUnicodeString(PCUNICODE_STRING aStr1,
PCUNICODE_STRING aStr2,
BOOLEAN aCaseInsensitive);
NTSTATUS NTAPI RtlGetVersion(PRTL_OSVERSIONINFOW aOutVersionInformation);
PVOID NTAPI RtlAllocateHeap(PVOID aHeapHandle, ULONG aFlags, SIZE_T aSize);
PVOID NTAPI RtlReAllocateHeap(PVOID aHeapHandle, ULONG aFlags, LPVOID aMem,
SIZE_T aNewSize);
BOOLEAN NTAPI RtlFreeHeap(PVOID aHeapHandle, ULONG aFlags, PVOID aHeapBase);
VOID NTAPI RtlAcquireSRWLockExclusive(PSRWLOCK aLock);
VOID NTAPI RtlReleaseSRWLockExclusive(PSRWLOCK aLock);
NTSTATUS NTAPI NtReadVirtualMemory(HANDLE aProcessHandle, PVOID aBaseAddress,
PVOID aBuffer, SIZE_T aNumBytesToRead,
PSIZE_T aNumBytesRead);
} // extern "C"
#endif // !defined(MOZILLA_INTERNAL_API)
namespace mozilla {
namespace nt {
#if !defined(MOZILLA_INTERNAL_API)
struct MemorySectionNameBuf : public _MEMORY_SECTION_NAME {
MemorySectionNameBuf() {
mSectionFileName.Length = 0;
mSectionFileName.MaximumLength = sizeof(mBuf);
mSectionFileName.Buffer = mBuf;
}
WCHAR mBuf[MAX_PATH];
};
inline bool FindCharInUnicodeString(const UNICODE_STRING& aStr, WCHAR aChar,
uint16_t& aPos, uint16_t aStartIndex = 0) {
const uint16_t aMaxIndex = aStr.Length / sizeof(WCHAR);
for (uint16_t curIndex = aStartIndex; curIndex < aMaxIndex; ++curIndex) {
if (aStr.Buffer[curIndex] == aChar) {
aPos = curIndex;
return true;
}
}
return false;
}
inline bool IsHexDigit(WCHAR aChar) {
return (aChar >= L'0' && aChar <= L'9') || (aChar >= L'A' && aChar <= L'F') ||
(aChar >= L'a' && aChar <= L'f');
}
inline bool MatchUnicodeString(const UNICODE_STRING& aStr,
bool (*aPredicate)(WCHAR)) {
WCHAR* cur = aStr.Buffer;
WCHAR* end = &aStr.Buffer[aStr.Length / sizeof(WCHAR)];
while (cur < end) {
if (!aPredicate(*cur)) {
return false;
}
++cur;
}
return true;
}
inline bool Contains12DigitHexString(const UNICODE_STRING& aLeafName) {
// Quick check: If the string is too short, don't bother
// (We need at least 12 hex digits, one char for '.', and 3 for extension)
const USHORT kMinLen = (12 + 1 + 3) * sizeof(wchar_t);
if (aLeafName.Length < kMinLen) {
return false;
}
uint16_t start, end;
if (!FindCharInUnicodeString(aLeafName, L'.', start)) {
return false;
}
++start;
if (!FindCharInUnicodeString(aLeafName, L'.', end, start)) {
return false;
}
if (end - start != 12) {
return false;
}
UNICODE_STRING test;
test.Buffer = &aLeafName.Buffer[start];
test.Length = (end - start) * sizeof(WCHAR);
test.MaximumLength = test.Length;
return MatchUnicodeString(test, &IsHexDigit);
}
inline bool IsFileNameAtLeast16HexDigits(const UNICODE_STRING& aLeafName) {
// Quick check: If the string is too short, don't bother
// (We need 16 hex digits, one char for '.', and 3 for extension)
const USHORT kMinLen = (16 + 1 + 3) * sizeof(wchar_t);
if (aLeafName.Length < kMinLen) {
return false;
}
uint16_t dotIndex;
if (!FindCharInUnicodeString(aLeafName, L'.', dotIndex)) {
return false;
}
if (dotIndex < 16) {
return false;
}
UNICODE_STRING test;
test.Buffer = aLeafName.Buffer;
test.Length = dotIndex * sizeof(WCHAR);
test.MaximumLength = aLeafName.MaximumLength;
return MatchUnicodeString(test, &IsHexDigit);
}
inline void GetLeafName(PUNICODE_STRING aDestString,
PCUNICODE_STRING aSrcString) {
WCHAR* buf = aSrcString->Buffer;
WCHAR* end = &aSrcString->Buffer[(aSrcString->Length / sizeof(WCHAR)) - 1];
WCHAR* cur = end;
while (cur >= buf) {
if (*cur == L'\\') {
break;
}
--cur;
}
// At this point, either cur points to the final backslash, or it points to
// buf - 1. Either way, we're interested in cur + 1 as the desired buffer.
aDestString->Buffer = cur + 1;
aDestString->Length = (end - aDestString->Buffer + 1) * sizeof(WCHAR);
aDestString->MaximumLength = aDestString->Length;
}
#endif // !defined(MOZILLA_INTERNAL_API)
inline char EnsureLowerCaseASCII(char aChar) {
if (aChar >= 'A' && aChar <= 'Z') {
aChar -= 'A' - 'a';
}
return aChar;
}
inline int StricmpASCII(const char* aLeft, const char* aRight) {
char curLeft, curRight;
do {
curLeft = EnsureLowerCaseASCII(*(aLeft++));
curRight = EnsureLowerCaseASCII(*(aRight++));
} while (curLeft && curLeft == curRight);
return curLeft - curRight;
}
class MOZ_RAII PEHeaders final {
/**
* This structure is documented on MSDN as VS_VERSIONINFO, but is not present
* in SDK headers because it cannot be specified as a C struct. The following
* structure contains the fixed-length fields at the beginning of
* VS_VERSIONINFO.
*/
struct VS_VERSIONINFO_HEADER {
WORD wLength;
WORD wValueLength;
WORD wType;
WCHAR szKey[16]; // ArrayLength(L"VS_VERSION_INFO")
// Additional data goes here, aligned on a 4-byte boundary
};
public:
// The lowest two bits of an HMODULE are used as flags. Stripping those bits
// from the HMODULE yields the base address of the binary's memory mapping.
// (See LoadLibraryEx docs on MSDN)
static PIMAGE_DOS_HEADER HModuleToBaseAddr(HMODULE aModule) {
return reinterpret_cast<PIMAGE_DOS_HEADER>(
reinterpret_cast<uintptr_t>(aModule) & ~uintptr_t(3));
}
explicit PEHeaders(void* aBaseAddress)
: PEHeaders(reinterpret_cast<PIMAGE_DOS_HEADER>(aBaseAddress)) {}
explicit PEHeaders(HMODULE aModule) : PEHeaders(HModuleToBaseAddr(aModule)) {}
explicit PEHeaders(PIMAGE_DOS_HEADER aMzHeader)
: mMzHeader(aMzHeader), mPeHeader(nullptr), mImageLimit(nullptr) {
if (!mMzHeader || mMzHeader->e_magic != IMAGE_DOS_SIGNATURE) {
return;
}
mPeHeader = RVAToPtrUnchecked<PIMAGE_NT_HEADERS>(mMzHeader->e_lfanew);
if (!mPeHeader || mPeHeader->Signature != IMAGE_NT_SIGNATURE) {
return;
}
if (mPeHeader->OptionalHeader.Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC) {
return;
}
DWORD imageSize = mPeHeader->OptionalHeader.SizeOfImage;
// This is a coarse-grained check to ensure that the image size is
// reasonable. It we aren't big enough to contain headers, we have a
// problem!
if (imageSize < sizeof(IMAGE_DOS_HEADER) + sizeof(IMAGE_NT_HEADERS)) {
return;
}
mImageLimit = RVAToPtrUnchecked<void*>(imageSize - 1UL);
}
explicit operator bool() const { return !!mImageLimit; }
/**
* This overload computes absolute virtual addresses relative to the base
* address of the binary.
*/
template <typename T, typename R>
T RVAToPtr(R aRva) const {
return RVAToPtr<T>(mMzHeader, aRva);
}
/**
* This overload computes a result by adding aRva to aBase, but also ensures
* that the resulting pointer falls within the bounds of this binary's memory
* mapping.
*/
template <typename T, typename R>
T RVAToPtr(void* aBase, R aRva) const {
if (!mImageLimit) {
return nullptr;
}
char* absAddress = reinterpret_cast<char*>(aBase) + aRva;
if (absAddress < reinterpret_cast<char*>(mMzHeader) ||
absAddress > reinterpret_cast<char*>(mImageLimit)) {
return nullptr;
}
return reinterpret_cast<T>(absAddress);
}
PIMAGE_IMPORT_DESCRIPTOR GetImportDirectory() {
return GetImageDirectoryEntry<PIMAGE_IMPORT_DESCRIPTOR>(
IMAGE_DIRECTORY_ENTRY_IMPORT);
}
PIMAGE_RESOURCE_DIRECTORY GetResourceTable() {
return GetImageDirectoryEntry<PIMAGE_RESOURCE_DIRECTORY>(
IMAGE_DIRECTORY_ENTRY_RESOURCE);
}
PIMAGE_DATA_DIRECTORY GetImageDirectoryEntryPtr(
const uint32_t aDirectoryIndex, uint32_t* aOutRva = nullptr) const {
if (aOutRva) {
*aOutRva = 0;
}
IMAGE_OPTIONAL_HEADER& optionalHeader = mPeHeader->OptionalHeader;
const uint32_t maxIndex = std::min(optionalHeader.NumberOfRvaAndSizes,
DWORD(IMAGE_NUMBEROF_DIRECTORY_ENTRIES));
if (aDirectoryIndex >= maxIndex) {
return nullptr;
}
PIMAGE_DATA_DIRECTORY dirEntry =
&optionalHeader.DataDirectory[aDirectoryIndex];
if (aOutRva) {
*aOutRva = reinterpret_cast<char*>(dirEntry) -
reinterpret_cast<char*>(mMzHeader);
MOZ_ASSERT(*aOutRva);
}
return dirEntry;
}
bool GetVersionInfo(uint64_t& aOutVersion) {
// RT_VERSION == 16
// Version resources require an id of 1
auto root = FindResourceLeaf<VS_VERSIONINFO_HEADER*>(16, 1);
if (!root) {
return false;
}
VS_FIXEDFILEINFO* fixedInfo = GetFixedFileInfo(root);
if (!fixedInfo) {
return false;
}
aOutVersion = ((static_cast<uint64_t>(fixedInfo->dwFileVersionMS) << 32) |
static_cast<uint64_t>(fixedInfo->dwFileVersionLS));
return true;
}
bool GetTimeStamp(DWORD& aResult) {
if (!(*this)) {
return false;
}
aResult = mPeHeader->FileHeader.TimeDateStamp;
return true;
}
PIMAGE_IMPORT_DESCRIPTOR
GetIATForModule(const char* aModuleNameASCII) {
for (PIMAGE_IMPORT_DESCRIPTOR curImpDesc = GetImportDirectory();
IsValid(curImpDesc); ++curImpDesc) {
auto curName = RVAToPtr<const char*>(curImpDesc->Name);
if (!curName) {
return nullptr;
}
if (StricmpASCII(aModuleNameASCII, curName)) {
continue;
}
// curImpDesc now points to the IAT for the module we're interested in
return curImpDesc;
}
return nullptr;
}
struct IATThunks {
IATThunks(PIMAGE_THUNK_DATA aFirstThunk, ptrdiff_t aNumThunks)
: mFirstThunk(aFirstThunk), mNumThunks(aNumThunks) {}
size_t Length() const {
return size_t(mNumThunks) * sizeof(IMAGE_THUNK_DATA);
}
PIMAGE_THUNK_DATA mFirstThunk;
ptrdiff_t mNumThunks;
};
Maybe<IATThunks> GetIATThunksForModule(const char* aModuleNameASCII) {
PIMAGE_IMPORT_DESCRIPTOR impDesc = GetIATForModule(aModuleNameASCII);
if (!impDesc) {
return Nothing();
}
auto firstIatThunk =
this->template RVAToPtr<PIMAGE_THUNK_DATA>(impDesc->FirstThunk);
if (!firstIatThunk) {
return Nothing();
}
// Find the length by iterating through the table until we find a null entry
PIMAGE_THUNK_DATA curIatThunk = firstIatThunk;
while (IsValid(curIatThunk)) {
++curIatThunk;
}
ptrdiff_t thunkCount = curIatThunk - firstIatThunk;
return Some(IATThunks(firstIatThunk, thunkCount));
}
/**
* Resources are stored in a three-level tree. To locate a particular entry,
* you must supply a resource type, the resource id, and then the language id.
* If aLangId == 0, we just resolve the first entry regardless of language.
*/
template <typename T>
T FindResourceLeaf(WORD aType, WORD aResId, WORD aLangId = 0) {
PIMAGE_RESOURCE_DIRECTORY topLevel = GetResourceTable();
if (!topLevel) {
return nullptr;
}
PIMAGE_RESOURCE_DIRECTORY_ENTRY typeEntry =
FindResourceEntry(topLevel, aType);
if (!typeEntry || !typeEntry->DataIsDirectory) {
return nullptr;
}
auto idDir = RVAToPtr<PIMAGE_RESOURCE_DIRECTORY>(
topLevel, typeEntry->OffsetToDirectory);
PIMAGE_RESOURCE_DIRECTORY_ENTRY idEntry = FindResourceEntry(idDir, aResId);
if (!idEntry || !idEntry->DataIsDirectory) {
return nullptr;
}
auto langDir = RVAToPtr<PIMAGE_RESOURCE_DIRECTORY>(
topLevel, idEntry->OffsetToDirectory);
PIMAGE_RESOURCE_DIRECTORY_ENTRY langEntry;
if (aLangId) {
langEntry = FindResourceEntry(langDir, aLangId);
} else {
langEntry = FindFirstResourceEntry(langDir);
}
if (!langEntry || langEntry->DataIsDirectory) {
return nullptr;
}
auto dataEntry =
RVAToPtr<PIMAGE_RESOURCE_DATA_ENTRY>(topLevel, langEntry->OffsetToData);
return RVAToPtr<T>(dataEntry->OffsetToData);
}
template <size_t N>
Maybe<Span<const uint8_t>> FindSection(const char (&aSecName)[N],
DWORD aCharacteristicsMask) const {
static_assert((N - 1) <= IMAGE_SIZEOF_SHORT_NAME,
"Section names must be at most 8 characters excluding null "
"terminator");
if (!(*this)) {
return Nothing();
}
Span<IMAGE_SECTION_HEADER> sectionTable = GetSectionTable();
for (auto&& sectionHeader : sectionTable) {
if (strncmp(reinterpret_cast<const char*>(sectionHeader.Name), aSecName,
IMAGE_SIZEOF_SHORT_NAME)) {
continue;
}
if (!(sectionHeader.Characteristics & aCharacteristicsMask)) {
// We found the section but it does not have the expected
// characteristics
return Nothing();
}
DWORD rva = sectionHeader.VirtualAddress;
if (!rva) {
return Nothing();
}
DWORD size = sectionHeader.Misc.VirtualSize;
if (!size) {
return Nothing();
}
auto base = RVAToPtr<const uint8_t*>(rva);
return Some(MakeSpan(base, size));
}
return Nothing();
}
// There may be other code sections in the binary besides .text
Maybe<Span<const uint8_t>> GetTextSectionInfo() const {
return FindSection(".text", IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE |
IMAGE_SCN_MEM_READ);
}
static bool IsValid(PIMAGE_IMPORT_DESCRIPTOR aImpDesc) {
return aImpDesc && aImpDesc->OriginalFirstThunk != 0;
}
static bool IsValid(PIMAGE_THUNK_DATA aImgThunk) {
return aImgThunk && aImgThunk->u1.Ordinal != 0;
}
private:
template <typename T>
T GetImageDirectoryEntry(const uint32_t aDirectoryIndex) {
PIMAGE_DATA_DIRECTORY dirEntry = GetImageDirectoryEntryPtr(aDirectoryIndex);
if (!dirEntry) {
return nullptr;
}
return RVAToPtr<T>(dirEntry->VirtualAddress);
}
// This private variant does not have bounds checks, because we need to be
// able to resolve the bounds themselves.
template <typename T, typename R>
T RVAToPtrUnchecked(R aRva) const {
return reinterpret_cast<T>(reinterpret_cast<char*>(mMzHeader) + aRva);
}
Span<IMAGE_SECTION_HEADER> GetSectionTable() const {
MOZ_ASSERT(*this);
auto base = RVAToPtr<PIMAGE_SECTION_HEADER>(
&mPeHeader->OptionalHeader, mPeHeader->FileHeader.SizeOfOptionalHeader);
// The Windows loader has an internal limit of 96 sections (per PE spec)
auto numSections =
std::min(mPeHeader->FileHeader.NumberOfSections, WORD(96));
return MakeSpan(base, numSections);
}
PIMAGE_RESOURCE_DIRECTORY_ENTRY
FindResourceEntry(PIMAGE_RESOURCE_DIRECTORY aCurLevel, WORD aId) {
// Immediately after the IMAGE_RESOURCE_DIRECTORY structure is an array
// of IMAGE_RESOURCE_DIRECTORY_ENTRY structures. Since this function
// searches by ID, we need to skip past any named entries before iterating.
auto dirEnt =
reinterpret_cast<PIMAGE_RESOURCE_DIRECTORY_ENTRY>(aCurLevel + 1) +
aCurLevel->NumberOfNamedEntries;
for (WORD i = 0; i < aCurLevel->NumberOfIdEntries; ++i) {
if (dirEnt[i].Id == aId) {
return &dirEnt[i];
}
}
return nullptr;
}
PIMAGE_RESOURCE_DIRECTORY_ENTRY
FindFirstResourceEntry(PIMAGE_RESOURCE_DIRECTORY aCurLevel) {
// Immediately after the IMAGE_RESOURCE_DIRECTORY structure is an array
// of IMAGE_RESOURCE_DIRECTORY_ENTRY structures. We just return the first
// entry, regardless of whether it is indexed by name or by id.
auto dirEnt =
reinterpret_cast<PIMAGE_RESOURCE_DIRECTORY_ENTRY>(aCurLevel + 1);
WORD numEntries =
aCurLevel->NumberOfNamedEntries + aCurLevel->NumberOfIdEntries;
if (!numEntries) {
return nullptr;
}
return dirEnt;
}
VS_FIXEDFILEINFO* GetFixedFileInfo(VS_VERSIONINFO_HEADER* aVerInfo) {
WORD length = aVerInfo->wLength;
if (length < sizeof(VS_VERSIONINFO_HEADER)) {
return nullptr;
}
const wchar_t kVersionInfoKey[] = L"VS_VERSION_INFO";
if (::RtlCompareMemory(aVerInfo->szKey, kVersionInfoKey,
ArrayLength(kVersionInfoKey)) !=
ArrayLength(kVersionInfoKey)) {
return nullptr;
}
if (aVerInfo->wValueLength != sizeof(VS_FIXEDFILEINFO)) {
// Fixed file info does not exist
return nullptr;
}
WORD offset = sizeof(VS_VERSIONINFO_HEADER);
uintptr_t base = reinterpret_cast<uintptr_t>(aVerInfo);
// Align up to 4-byte boundary
#pragma warning(suppress : 4146)
offset += (-(base + offset) & 3);
if (offset >= length) {
return nullptr;
}
auto result = reinterpret_cast<VS_FIXEDFILEINFO*>(base + offset);
if (result->dwSignature != 0xFEEF04BD) {
return nullptr;
}
return result;
}
private:
PIMAGE_DOS_HEADER mMzHeader;
PIMAGE_NT_HEADERS mPeHeader;
void* mImageLimit;
};
inline HANDLE RtlGetProcessHeap() {
PTEB teb = ::NtCurrentTeb();
PPEB peb = teb->ProcessEnvironmentBlock;
return peb->Reserved4[1];
}
inline LauncherResult<DWORD> GetParentProcessId() {
struct PROCESS_BASIC_INFORMATION {
NTSTATUS ExitStatus;
PPEB PebBaseAddress;
ULONG_PTR AffinityMask;
LONG BasePriority;
ULONG_PTR UniqueProcessId;
ULONG_PTR InheritedFromUniqueProcessId;
};
const HANDLE kCurrentProcess = reinterpret_cast<HANDLE>(-1);
ULONG returnLength;
PROCESS_BASIC_INFORMATION pbi = {};
NTSTATUS status =
::NtQueryInformationProcess(kCurrentProcess, ProcessBasicInformation,
&pbi, sizeof(pbi), &returnLength);
if (!NT_SUCCESS(status)) {
return LAUNCHER_ERROR_FROM_NTSTATUS(status);
}
return static_cast<DWORD>(pbi.InheritedFromUniqueProcessId & 0xFFFFFFFF);
}
struct DataDirectoryEntry : public _IMAGE_DATA_DIRECTORY {
DataDirectoryEntry() : _IMAGE_DATA_DIRECTORY() {}
MOZ_IMPLICIT DataDirectoryEntry(const _IMAGE_DATA_DIRECTORY& aOther)
: _IMAGE_DATA_DIRECTORY(aOther) {}
DataDirectoryEntry(const DataDirectoryEntry& aOther) = default;
};
inline LauncherResult<void*> GetProcessPebPtr(HANDLE aProcess) {
ULONG returnLength;
PROCESS_BASIC_INFORMATION pbi;
NTSTATUS status = ::NtQueryInformationProcess(
aProcess, ProcessBasicInformation, &pbi, sizeof(pbi), &returnLength);
if (!NT_SUCCESS(status)) {
return LAUNCHER_ERROR_FROM_NTSTATUS(status);
}
return pbi.PebBaseAddress;
}
/**
* This function relies on a specific offset into the mostly-undocumented PEB
* structure. The risk is reduced thanks to the fact that the Chromium sandbox
* relies on the location of this field. It is unlikely to change at this point.
* To further reduce the risk, we also check for the magic 'MZ' signature that
* should indicate the beginning of a PE image.
*/
inline LauncherResult<HMODULE> GetProcessExeModule(HANDLE aProcess) {
LauncherResult<void*> ppeb = GetProcessPebPtr(aProcess);
if (ppeb.isErr()) {
return LAUNCHER_ERROR_FROM_RESULT(ppeb);
}
PEB peb;
SIZE_T bytesRead;
#if defined(MOZILLA_INTERNAL_API)
if (!::ReadProcessMemory(aProcess, ppeb.unwrap(), &peb, sizeof(peb),
&bytesRead) ||
bytesRead != sizeof(peb)) {
return LAUNCHER_ERROR_FROM_LAST();
}
#else
NTSTATUS ntStatus = ::NtReadVirtualMemory(aProcess, ppeb.unwrap(), &peb,
sizeof(peb), &bytesRead);
if (!NT_SUCCESS(ntStatus) || bytesRead != sizeof(peb)) {
return LAUNCHER_ERROR_FROM_NTSTATUS(ntStatus);
}
#endif
// peb.ImageBaseAddress
void* baseAddress = peb.Reserved3[1];
char mzMagic[2];
#if defined(MOZILLA_INTERNAL_API)
if (!::ReadProcessMemory(aProcess, baseAddress, mzMagic, sizeof(mzMagic),
&bytesRead) ||
bytesRead != sizeof(mzMagic)) {
return LAUNCHER_ERROR_FROM_LAST();
}
#else
ntStatus = ::NtReadVirtualMemory(aProcess, baseAddress, mzMagic,
sizeof(mzMagic), &bytesRead);
if (!NT_SUCCESS(ntStatus) || bytesRead != sizeof(mzMagic)) {
return LAUNCHER_ERROR_FROM_NTSTATUS(ntStatus);
}
#endif
MOZ_ASSERT(mzMagic[0] == 'M' && mzMagic[1] == 'Z');
if (mzMagic[0] != 'M' || mzMagic[1] != 'Z') {
return LAUNCHER_ERROR_FROM_WIN32(ERROR_BAD_EXE_FORMAT);
}
return static_cast<HMODULE>(baseAddress);
}
} // namespace nt
} // namespace mozilla
#endif // mozilla_NativeNt_h