mozglue/misc/NativeNt.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_NativeNt_h
   8 #define mozilla_NativeNt_h
   9
  10 #include <stdint.h>
  11 #include <windows.h>
  12 #include <winnt.h>
  13 #include <winternl.h>
  14
  15 #include <algorithm>
  16 #include <utility>
  17
  18 #include "mozilla/ArrayUtils.h"
  19 #include "mozilla/Attributes.h"
  20 #include "mozilla/DebugOnly.h"
  21 #include "mozilla/Maybe.h"
  22 #include "mozilla/Range.h"
  23 #include "mozilla/Span.h"
  24 #include "mozilla/WinHeaderOnlyUtils.h"
  25 #include "mozilla/interceptor/MMPolicies.h"
  26 #include "mozilla/interceptor/TargetFunction.h"
  27
  28 #if defined(MOZILLA_INTERNAL_API)
  29 #  include "nsString.h"
  30 #endif  // defined(MOZILLA_INTERNAL_API)
  31
  32 // The declarations within this #if block are intended to be used for initial
  33 // process initialization ONLY. You probably don't want to be using these in
  34 // normal Gecko code!
  35 #if !defined(MOZILLA_INTERNAL_API)
  36
  37 extern "C" {
  38
  39 #  if !defined(STATUS_ACCESS_DENIED)
  40 #    define STATUS_ACCESS_DENIED ((NTSTATUS)0xC0000022L)
  41 #  endif  // !defined(STATUS_ACCESS_DENIED)
  42
  43 #  if !defined(STATUS_DLL_NOT_FOUND)
  44 #    define STATUS_DLL_NOT_FOUND ((NTSTATUS)0xC0000135L)
  45 #  endif  // !defined(STATUS_DLL_NOT_FOUND)
  46
  47 #  if !defined(STATUS_UNSUCCESSFUL)
  48 #    define STATUS_UNSUCCESSFUL ((NTSTATUS)0xC0000001L)
  49 #  endif  // !defined(STATUS_UNSUCCESSFUL)
  50
  51 #  if !defined(STATUS_INFO_LENGTH_MISMATCH)
  52 #    define STATUS_INFO_LENGTH_MISMATCH ((NTSTATUS)0xC0000004L)
  53 #  endif
  54
  55 enum SECTION_INHERIT { ViewShare = 1, ViewUnmap = 2 };
  56
  57 NTSTATUS NTAPI NtMapViewOfSection(
  58     HANDLE aSection, HANDLE aProcess, PVOID* aBaseAddress, ULONG_PTR aZeroBits,
  59     SIZE_T aCommitSize, PLARGE_INTEGER aSectionOffset, PSIZE_T aViewSize,
  60     SECTION_INHERIT aInheritDisposition, ULONG aAllocationType,
  61     ULONG aProtectionFlags);
  62
  63 NTSTATUS NTAPI NtUnmapViewOfSection(HANDLE aProcess, PVOID aBaseAddress);
  64
  65 enum MEMORY_INFORMATION_CLASS {
  66   MemoryBasicInformation = 0,
  67   MemorySectionName = 2
  68 };
  69
  70 // NB: When allocating, space for the buffer must also be included
  71 typedef struct _MEMORY_SECTION_NAME {
  72   UNICODE_STRING mSectionFileName;
  73 } MEMORY_SECTION_NAME, *PMEMORY_SECTION_NAME;
  74
  75 NTSTATUS NTAPI NtQueryVirtualMemory(HANDLE aProcess, PVOID aBaseAddress,
  76                                     MEMORY_INFORMATION_CLASS aMemInfoClass,
  77                                     PVOID aMemInfo, SIZE_T aMemInfoLen,
  78                                     PSIZE_T aReturnLen);
  79
  80 LONG NTAPI RtlCompareUnicodeString(PCUNICODE_STRING aStr1,
  81                                    PCUNICODE_STRING aStr2,
  82                                    BOOLEAN aCaseInsensitive);
  83
  84 BOOLEAN NTAPI RtlEqualUnicodeString(PCUNICODE_STRING aStr1,
  85                                     PCUNICODE_STRING aStr2,
  86                                     BOOLEAN aCaseInsensitive);
  87
  88 NTSTATUS NTAPI RtlGetVersion(PRTL_OSVERSIONINFOW aOutVersionInformation);
  89
  90 VOID NTAPI RtlAcquireSRWLockExclusive(PSRWLOCK aLock);
  91 VOID NTAPI RtlAcquireSRWLockShared(PSRWLOCK aLock);
  92
  93 VOID NTAPI RtlReleaseSRWLockExclusive(PSRWLOCK aLock);
  94 VOID NTAPI RtlReleaseSRWLockShared(PSRWLOCK aLock);
  95
  96 NTSTATUS NTAPI RtlSleepConditionVariableSRW(
  97     PCONDITION_VARIABLE aConditionVariable, PSRWLOCK aSRWLock,
  98     PLARGE_INTEGER aTimeOut, ULONG aFlags);
  99 VOID NTAPI RtlWakeAllConditionVariable(PCONDITION_VARIABLE aConditionVariable);
 100
 101 ULONG NTAPI RtlNtStatusToDosError(NTSTATUS aStatus);
 102 VOID NTAPI RtlSetLastWin32Error(DWORD aError);
 103 DWORD NTAPI RtlGetLastWin32Error();
 104
 105 VOID NTAPI RtlRunOnceInitialize(PRTL_RUN_ONCE aRunOnce);
 106
 107 NTSTATUS NTAPI NtReadVirtualMemory(HANDLE aProcessHandle, PVOID aBaseAddress,
 108                                    PVOID aBuffer, SIZE_T aNumBytesToRead,
 109                                    PSIZE_T aNumBytesRead);
 110
 111 NTSTATUS NTAPI LdrLoadDll(PWCHAR aDllPath, PULONG aFlags,
 112                           PUNICODE_STRING aDllName, PHANDLE aOutHandle);
 113
 114 typedef ULONG(NTAPI* PRTL_RUN_ONCE_INIT_FN)(PRTL_RUN_ONCE, PVOID, PVOID*);
 115 NTSTATUS NTAPI RtlRunOnceExecuteOnce(PRTL_RUN_ONCE aRunOnce,
 116                                      PRTL_RUN_ONCE_INIT_FN aInitFn,
 117                                      PVOID aContext, PVOID* aParameter);
 118
 119 }  // extern "C"
 120
 121 #endif  // !defined(MOZILLA_INTERNAL_API)
 122
 123 extern "C" {
 124 PVOID NTAPI RtlAllocateHeap(PVOID aHeapHandle, ULONG aFlags, SIZE_T aSize);
 125
 126 PVOID NTAPI RtlReAllocateHeap(PVOID aHeapHandle, ULONG aFlags, LPVOID aMem,
 127                               SIZE_T aNewSize);
 128
 129 BOOLEAN NTAPI RtlFreeHeap(PVOID aHeapHandle, ULONG aFlags, PVOID aHeapBase);
 130
 131 BOOLEAN NTAPI RtlQueryPerformanceCounter(LARGE_INTEGER* aPerfCount);
 132
 133 #define RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE 1
 134 #define RTL_DUPLICATE_UNICODE_STRING_ALLOCATE_NULL_STRING 2
 135 NTSTATUS NTAPI RtlDuplicateUnicodeString(ULONG aFlags, PCUNICODE_STRING aSrc,
 136                                          PUNICODE_STRING aDest);
 137
 138 VOID NTAPI RtlFreeUnicodeString(PUNICODE_STRING aUnicodeString);
 139 }  // extern "C"
 140
 141 namespace mozilla {
 142 namespace nt {
 143
 144 /**
 145  * This class encapsulates a UNICODE_STRING that owns its own buffer. The
 146  * buffer is always NULL terminated, thus allowing us to cast to a wide C-string
 147  * without requiring any mutation.
 148  *
 149  * We only allow creation of this owned buffer from outside XUL.
 150  */
 151 class AllocatedUnicodeString final {
 152  public:
 153   AllocatedUnicodeString() : mUnicodeString() {}
 154
 155 #if defined(MOZILLA_INTERNAL_API)
 156   AllocatedUnicodeString(const AllocatedUnicodeString& aOther) = delete;
 157
 158   AllocatedUnicodeString& operator=(const AllocatedUnicodeString& aOther) =
 159       delete;
 160 #else
 161   explicit AllocatedUnicodeString(PCUNICODE_STRING aSrc) {
 162     if (!aSrc) {
 163       mUnicodeString = {};
 164       return;
 165     }
 166
 167     Duplicate(aSrc);
 168   }
 169
 170   explicit AllocatedUnicodeString(const char* aSrc) {
 171     if (!aSrc) {
 172       mUnicodeString = {};
 173       return;
 174     }
 175
 176     Duplicate(aSrc);
 177   }
 178
 179   AllocatedUnicodeString(const AllocatedUnicodeString& aOther) {
 180     Duplicate(&aOther.mUnicodeString);
 181   }
 182
 183   AllocatedUnicodeString& operator=(const AllocatedUnicodeString& aOther) {
 184     Clear();
 185     Duplicate(&aOther.mUnicodeString);
 186     return *this;
 187   }
 188
 189   AllocatedUnicodeString& operator=(PCUNICODE_STRING aSrc) {
 190     Clear();
 191     Duplicate(aSrc);
 192     return *this;
 193   }
 194 #endif  // defined(MOZILLA_INTERNAL_API)
 195
 196   AllocatedUnicodeString(AllocatedUnicodeString&& aOther)
 197       : mUnicodeString(aOther.mUnicodeString) {
 198     aOther.mUnicodeString = {};
 199   }
 200
 201   AllocatedUnicodeString& operator=(AllocatedUnicodeString&& aOther) {
 202     Clear();
 203     mUnicodeString = aOther.mUnicodeString;
 204     aOther.mUnicodeString = {};
 205     return *this;
 206   }
 207
 208   ~AllocatedUnicodeString() { Clear(); }
 209
 210   bool IsEmpty() const {
 211     return !mUnicodeString.Buffer || !mUnicodeString.Length;
 212   }
 213
 214   operator PCUNICODE_STRING() const { return &mUnicodeString; }
 215
 216   operator const WCHAR*() const { return mUnicodeString.Buffer; }
 217
 218   USHORT CharLen() const { return mUnicodeString.Length / sizeof(WCHAR); }
 219
 220 #if defined(MOZILLA_INTERNAL_API)
 221   nsDependentString AsString() const {
 222     if (!mUnicodeString.Buffer) {
 223       return nsDependentString();
 224     }
 225
 226     // We can use nsDependentString here as we guaranteed null termination
 227     // when we allocated the string.
 228     return nsDependentString(mUnicodeString.Buffer, CharLen());
 229   }
 230 #endif  // defined(MOZILLA_INTERNAL_API)
 231
 232  private:
 233 #if !defined(MOZILLA_INTERNAL_API)
 234   void Duplicate(PCUNICODE_STRING aSrc) {
 235     MOZ_ASSERT(aSrc);
 236
 237     // We duplicate with null termination so that this string may be used
 238     // as a wide C-string without any further manipulation.
 239     NTSTATUS ntStatus = ::RtlDuplicateUnicodeString(
 240         RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE, aSrc, &mUnicodeString);
 241     MOZ_ASSERT(NT_SUCCESS(ntStatus));
 242     if (!NT_SUCCESS(ntStatus)) {
 243       // Make sure that mUnicodeString does not contain bogus data
 244       // (since not all callers zero it out before invoking)
 245       mUnicodeString = {};
 246     }
 247   }
 248
 249   void Duplicate(const char* aSrc) {
 250     MOZ_ASSERT(aSrc);
 251
 252     ANSI_STRING ansiStr;
 253     RtlInitAnsiString(&ansiStr, aSrc);
 254     NTSTATUS ntStatus =
 255         ::RtlAnsiStringToUnicodeString(&mUnicodeString, &ansiStr, TRUE);
 256     MOZ_ASSERT(NT_SUCCESS(ntStatus));
 257     if (!NT_SUCCESS(ntStatus)) {
 258       mUnicodeString = {};
 259     }
 260   }
 261 #endif  // !defined(MOZILLA_INTERNAL_API)
 262
 263   void Clear() {
 264     if (!mUnicodeString.Buffer) {
 265       return;
 266     }
 267
 268     ::RtlFreeUnicodeString(&mUnicodeString);
 269     mUnicodeString = {};
 270   }
 271
 272   UNICODE_STRING mUnicodeString;
 273 };
 274
 275 #if !defined(MOZILLA_INTERNAL_API)
 276
 277 struct MemorySectionNameBuf : public _MEMORY_SECTION_NAME {
 278   MemorySectionNameBuf() {
 279     mSectionFileName.Length = 0;
 280     mSectionFileName.MaximumLength = sizeof(mBuf);
 281     mSectionFileName.Buffer = mBuf;
 282   }
 283
 284   MemorySectionNameBuf(const MemorySectionNameBuf& aOther) { *this = aOther; }
 285
 286   MemorySectionNameBuf(MemorySectionNameBuf&& aOther) {
 287     *this = std::move(aOther);
 288   }
 289
 290   // We cannot use default copy here because mSectionFileName.Buffer needs to
 291   // be updated to point to |this->mBuf|, not |aOther.mBuf|.
 292   MemorySectionNameBuf& operator=(const MemorySectionNameBuf& aOther) {
 293     mSectionFileName.Length = aOther.mSectionFileName.Length;
 294     mSectionFileName.MaximumLength = sizeof(mBuf);
 295     MOZ_ASSERT(mSectionFileName.Length <= mSectionFileName.MaximumLength);
 296     mSectionFileName.Buffer = mBuf;
 297     memcpy(mBuf, aOther.mBuf, aOther.mSectionFileName.Length);
 298     return *this;
 299   }
 300
 301   MemorySectionNameBuf& operator=(MemorySectionNameBuf&& aOther) {
 302     mSectionFileName.Length = aOther.mSectionFileName.Length;
 303     aOther.mSectionFileName.Length = 0;
 304     mSectionFileName.MaximumLength = sizeof(mBuf);
 305     MOZ_ASSERT(mSectionFileName.Length <= mSectionFileName.MaximumLength);
 306     aOther.mSectionFileName.MaximumLength = sizeof(aOther.mBuf);
 307     mSectionFileName.Buffer = mBuf;
 308     memmove(mBuf, aOther.mBuf, mSectionFileName.Length);
 309     return *this;
 310   }
 311
 312   // Native NT paths, so we can't assume MAX_PATH. Use a larger buffer.
 313   WCHAR mBuf[2 * MAX_PATH];
 314
 315   bool IsEmpty() const {
 316     return !mSectionFileName.Buffer || !mSectionFileName.Length;
 317   }
 318
 319   operator PCUNICODE_STRING() const { return &mSectionFileName; }
 320 };
 321
 322 class MemorySectionNameOnHeap {
 323   UniquePtr<uint8_t[]> mBuffer;
 324
 325   MemorySectionNameOnHeap() = default;
 326   explicit MemorySectionNameOnHeap(size_t aBufferLen)
 327       : mBuffer(MakeUnique<uint8_t[]>(aBufferLen)) {}
 328
 329  public:
 330   static MemorySectionNameOnHeap GetBackingFilePath(HANDLE aProcess,
 331                                                     void* aSectionAddr) {
 332     SIZE_T bufferLen = MAX_PATH * 2;
 333     do {
 334       MemorySectionNameOnHeap sectionName(bufferLen);
 335
 336       SIZE_T requiredBytes;
 337       NTSTATUS ntStatus = ::NtQueryVirtualMemory(
 338           aProcess, aSectionAddr, MemorySectionName, sectionName.mBuffer.get(),
 339           bufferLen, &requiredBytes);
 340       if (NT_SUCCESS(ntStatus)) {
 341         return sectionName;
 342       }
 343
 344       if (ntStatus != STATUS_INFO_LENGTH_MISMATCH ||
 345           bufferLen >= requiredBytes) {
 346         break;
 347       }
 348
 349       bufferLen = requiredBytes;
 350     } while (1);
 351
 352     return MemorySectionNameOnHeap();
 353   }
 354
 355   // Allow move & Disallow copy
 356   MemorySectionNameOnHeap(MemorySectionNameOnHeap&&) = default;
 357   MemorySectionNameOnHeap& operator=(MemorySectionNameOnHeap&&) = default;
 358   MemorySectionNameOnHeap(const MemorySectionNameOnHeap&) = delete;
 359   MemorySectionNameOnHeap& operator=(const MemorySectionNameOnHeap&) = delete;
 360
 361   PCUNICODE_STRING AsUnicodeString() const {
 362     return reinterpret_cast<PCUNICODE_STRING>(mBuffer.get());
 363   }
 364 };
 365
 366 inline bool FindCharInUnicodeString(const UNICODE_STRING& aStr, WCHAR aChar,
 367                                     uint16_t& aPos, uint16_t aStartIndex = 0) {
 368   const uint16_t aMaxIndex = aStr.Length / sizeof(WCHAR);
 369
 370   for (uint16_t curIndex = aStartIndex; curIndex < aMaxIndex; ++curIndex) {
 371     if (aStr.Buffer[curIndex] == aChar) {
 372       aPos = curIndex;
 373       return true;
 374     }
 375   }
 376
 377   return false;
 378 }
 379
 380 inline bool IsHexDigit(WCHAR aChar) {
 381   return (aChar >= L'0' && aChar <= L'9') || (aChar >= L'A' && aChar <= L'F') ||
 382          (aChar >= L'a' && aChar <= L'f');
 383 }
 384
 385 inline bool MatchUnicodeString(const UNICODE_STRING& aStr,
 386                                bool (*aPredicate)(WCHAR)) {
 387   WCHAR* cur = aStr.Buffer;
 388   WCHAR* end = &aStr.Buffer[aStr.Length / sizeof(WCHAR)];
 389   while (cur < end) {
 390     if (!aPredicate(*cur)) {
 391       return false;
 392     }
 393
 394     ++cur;
 395   }
 396
 397   return true;
 398 }
 399
 400 inline bool Contains12DigitHexString(const UNICODE_STRING& aLeafName) {
 401   // Quick check: If the string is too short, don't bother
 402   // (We need at least 12 hex digits, one char for '.', and 3 for extension)
 403   const USHORT kMinLen = (12 + 1 + 3) * sizeof(wchar_t);
 404   if (aLeafName.Length < kMinLen) {
 405     return false;
 406   }
 407
 408   uint16_t start, end;
 409   if (!FindCharInUnicodeString(aLeafName, L'.', start)) {
 410     return false;
 411   }
 412
 413   ++start;
 414   if (!FindCharInUnicodeString(aLeafName, L'.', end, start)) {
 415     return false;
 416   }
 417
 418   if (end - start != 12) {
 419     return false;
 420   }
 421
 422   UNICODE_STRING test;
 423   test.Buffer = &aLeafName.Buffer[start];
 424   test.Length = (end - start) * sizeof(WCHAR);
 425   test.MaximumLength = test.Length;
 426
 427   return MatchUnicodeString(test, &IsHexDigit);
 428 }
 429
 430 inline bool IsFileNameAtLeast16HexDigits(const UNICODE_STRING& aLeafName) {
 431   // Quick check: If the string is too short, don't bother
 432   // (We need 16 hex digits, one char for '.', and 3 for extension)
 433   const USHORT kMinLen = (16 + 1 + 3) * sizeof(wchar_t);
 434   if (aLeafName.Length < kMinLen) {
 435     return false;
 436   }
 437
 438   uint16_t dotIndex;
 439   if (!FindCharInUnicodeString(aLeafName, L'.', dotIndex)) {
 440     return false;
 441   }
 442
 443   if (dotIndex < 16) {
 444     return false;
 445   }
 446
 447   UNICODE_STRING test;
 448   test.Buffer = aLeafName.Buffer;
 449   test.Length = dotIndex * sizeof(WCHAR);
 450   test.MaximumLength = aLeafName.MaximumLength;
 451
 452   return MatchUnicodeString(test, &IsHexDigit);
 453 }
 454
 455 inline void GetLeafName(PUNICODE_STRING aDestString,
 456                         PCUNICODE_STRING aSrcString) {
 457   WCHAR* buf = aSrcString->Buffer;
 458   WCHAR* end = &aSrcString->Buffer[(aSrcString->Length / sizeof(WCHAR)) - 1];
 459   WCHAR* cur = end;
 460   while (cur >= buf) {
 461     if (*cur == L'\\') {
 462       break;
 463     }
 464
 465     --cur;
 466   }
 467
 468   // At this point, either cur points to the final backslash, or it points to
 469   // buf - 1. Either way, we're interested in cur + 1 as the desired buffer.
 470   aDestString->Buffer = cur + 1;
 471   aDestString->Length = (end - aDestString->Buffer + 1) * sizeof(WCHAR);
 472   aDestString->MaximumLength = aDestString->Length;
 473 }
 474
 475 #endif  // !defined(MOZILLA_INTERNAL_API)
 476
 477 #if defined(MOZILLA_INTERNAL_API)
 478
 479 inline const nsDependentSubstring GetLeafName(const nsAString& aString) {
 480   auto it = aString.EndReading();
 481   size_t pos = aString.Length();
 482   while (it > aString.BeginReading()) {
 483     if (*(it - 1) == u'\\') {
 484       return Substring(aString, pos);
 485     }
 486
 487     MOZ_ASSERT(pos > 0);
 488     --pos;
 489     --it;
 490   }
 491
 492   return Substring(aString, 0);  // No backslash in the string
 493 }
 494
 495 #endif  // defined(MOZILLA_INTERNAL_API)
 496
 497 inline char EnsureLowerCaseASCII(char aChar) {
 498   if (aChar >= 'A' && aChar <= 'Z') {
 499     aChar -= 'A' - 'a';
 500   }
 501
 502   return aChar;
 503 }
 504
 505 inline int StricmpASCII(const char* aLeft, const char* aRight) {
 506   char curLeft, curRight;
 507
 508   do {
 509     curLeft = EnsureLowerCaseASCII(*(aLeft++));
 510     curRight = EnsureLowerCaseASCII(*(aRight++));
 511   } while (curLeft && curLeft == curRight);
 512
 513   return curLeft - curRight;
 514 }
 515
 516 inline int StrcmpASCII(const char* aLeft, const char* aRight) {
 517   char curLeft, curRight;
 518
 519   do {
 520     curLeft = *(aLeft++);
 521     curRight = *(aRight++);
 522   } while (curLeft && curLeft == curRight);
 523
 524   return curLeft - curRight;
 525 }
 526
 527 inline size_t StrlenASCII(const char* aStr) {
 528   size_t len = 0;
 529
 530   while (*(aStr++)) {
 531     ++len;
 532   }
 533
 534   return len;
 535 }
 536
 537 struct CodeViewRecord70 {
 538   uint32_t signature;
 539   GUID pdbSignature;
 540   uint32_t pdbAge;
 541   // A UTF-8 string, according to
 542   // https://github.com/Microsoft/microsoft-pdb/blob/082c5290e5aff028ae84e43affa8be717aa7af73/PDB/dbi/locator.cpp#L785
 543   char pdbFileName[1];
 544 };
 545
 546 class MOZ_RAII PEHeaders final {
 547   /**
 548    * This structure is documented on MSDN as VS_VERSIONINFO, but is not present
 549    * in SDK headers because it cannot be specified as a C struct. The following
 550    * structure contains the fixed-length fields at the beginning of
 551    * VS_VERSIONINFO.
 552    */
 553   struct VS_VERSIONINFO_HEADER {
 554     WORD wLength;
 555     WORD wValueLength;
 556     WORD wType;
 557     WCHAR szKey[16];  // ArrayLength(L"VS_VERSION_INFO")
 558     // Additional data goes here, aligned on a 4-byte boundary
 559   };
 560
 561  public:
 562   // The lowest two bits of an HMODULE are used as flags. Stripping those bits
 563   // from the HMODULE yields the base address of the binary's memory mapping.
 564   // (See LoadLibraryEx docs on MSDN)
 565   template <typename T>
 566   static T HModuleToBaseAddr(HMODULE aModule) {
 567     return reinterpret_cast<T>(reinterpret_cast<uintptr_t>(aModule) &
 568                                ~uintptr_t(3));
 569   }
 570
 571   explicit PEHeaders(void* aBaseAddress)
 572       : PEHeaders(reinterpret_cast<PIMAGE_DOS_HEADER>(aBaseAddress)) {}
 573
 574   explicit PEHeaders(HMODULE aModule)
 575       : PEHeaders(HModuleToBaseAddr<PIMAGE_DOS_HEADER>(aModule)) {}
 576
 577   explicit PEHeaders(PIMAGE_DOS_HEADER aMzHeader)
 578       : mMzHeader(aMzHeader),
 579         mPeHeader(nullptr),
 580         mImageLimit(nullptr),
 581         mIsImportDirectoryTampered(false) {
 582     if (!mMzHeader || mMzHeader->e_magic != IMAGE_DOS_SIGNATURE) {
 583       return;
 584     }
 585
 586     mPeHeader = RVAToPtrUnchecked<PIMAGE_NT_HEADERS>(mMzHeader->e_lfanew);
 587     if (!mPeHeader || mPeHeader->Signature != IMAGE_NT_SIGNATURE) {
 588       return;
 589     }
 590
 591     if (mPeHeader->OptionalHeader.Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC) {
 592       return;
 593     }
 594
 595     DWORD imageSize = mPeHeader->OptionalHeader.SizeOfImage;
 596     // This is a coarse-grained check to ensure that the image size is
 597     // reasonable. It we aren't big enough to contain headers, we have a
 598     // problem!
 599     if (imageSize < sizeof(IMAGE_DOS_HEADER) + sizeof(IMAGE_NT_HEADERS)) {
 600       return;
 601     }
 602
 603     mImageLimit = RVAToPtrUnchecked<void*>(imageSize - 1UL);
 604
 605     PIMAGE_DATA_DIRECTORY importDirEntry =
 606         GetImageDirectoryEntryPtr(IMAGE_DIRECTORY_ENTRY_IMPORT);
 607     if (!importDirEntry) {
 608       return;
 609     }
 610
 611     mIsImportDirectoryTampered = (importDirEntry->VirtualAddress >= imageSize);
 612   }
 613
 614   explicit operator bool() const { return !!mImageLimit; }
 615
 616   /**
 617    * This overload computes absolute virtual addresses relative to the base
 618    * address of the binary.
 619    */
 620   template <typename T, typename R>
 621   T RVAToPtr(R aRva) const {
 622     return RVAToPtr<T>(mMzHeader, aRva);
 623   }
 624
 625   /**
 626    * This overload computes a result by adding aRva to aBase, but also ensures
 627    * that the resulting pointer falls within the bounds of this binary's memory
 628    * mapping.
 629    */
 630   template <typename T, typename R>
 631   T RVAToPtr(void* aBase, R aRva) const {
 632     if (!mImageLimit) {
 633       return nullptr;
 634     }
 635
 636     char* absAddress = reinterpret_cast<char*>(aBase) + aRva;
 637     if (absAddress < reinterpret_cast<char*>(mMzHeader) ||
 638         absAddress > reinterpret_cast<char*>(mImageLimit)) {
 639       return nullptr;
 640     }
 641
 642     return reinterpret_cast<T>(absAddress);
 643   }
 644
 645   Maybe<Range<const uint8_t>> GetBounds() const {
 646     if (!mImageLimit) {
 647       return Nothing();
 648     }
 649
 650     auto base = reinterpret_cast<const uint8_t*>(mMzHeader);
 651     DWORD imageSize = mPeHeader->OptionalHeader.SizeOfImage;
 652     return Some(Range(base, imageSize));
 653   }
 654
 655   DWORD GetFileCharacteristics() const {
 656     return mPeHeader ? mPeHeader->FileHeader.Characteristics : 0;
 657   }
 658
 659   bool IsWithinImage(const void* aAddress) const {
 660     uintptr_t addr = reinterpret_cast<uintptr_t>(aAddress);
 661     uintptr_t imageBase = reinterpret_cast<uintptr_t>(mMzHeader);
 662     uintptr_t imageLimit = reinterpret_cast<uintptr_t>(mImageLimit);
 663     return addr >= imageBase && addr <= imageLimit;
 664   }
 665
 666   PIMAGE_IMPORT_DESCRIPTOR GetImportDirectory() const {
 667     // If the import directory is already tampered, we skip bounds check
 668     // because it could be located outside the mapped image.
 669     return mIsImportDirectoryTampered
 670                ? GetImageDirectoryEntry<PIMAGE_IMPORT_DESCRIPTOR,
 671                                         BoundsCheckPolicy::Skip>(
 672                      IMAGE_DIRECTORY_ENTRY_IMPORT)
 673                : GetImageDirectoryEntry<PIMAGE_IMPORT_DESCRIPTOR>(
 674                      IMAGE_DIRECTORY_ENTRY_IMPORT);
 675   }
 676
 677   PIMAGE_RESOURCE_DIRECTORY GetResourceTable() const {
 678     return GetImageDirectoryEntry<PIMAGE_RESOURCE_DIRECTORY>(
 679         IMAGE_DIRECTORY_ENTRY_RESOURCE);
 680   }
 681
 682   PIMAGE_DATA_DIRECTORY GetImageDirectoryEntryPtr(
 683       const uint32_t aDirectoryIndex, uint32_t* aOutRva = nullptr) const {
 684     if (aOutRva) {
 685       *aOutRva = 0;
 686     }
 687
 688     IMAGE_OPTIONAL_HEADER& optionalHeader = mPeHeader->OptionalHeader;
 689
 690     const uint32_t maxIndex = std::min(optionalHeader.NumberOfRvaAndSizes,
 691                                        DWORD(IMAGE_NUMBEROF_DIRECTORY_ENTRIES));
 692     if (aDirectoryIndex >= maxIndex) {
 693       return nullptr;
 694     }
 695
 696     PIMAGE_DATA_DIRECTORY dirEntry =
 697         &optionalHeader.DataDirectory[aDirectoryIndex];
 698     if (aOutRva) {
 699       *aOutRva = reinterpret_cast<char*>(dirEntry) -
 700                  reinterpret_cast<char*>(mMzHeader);
 701       MOZ_ASSERT(*aOutRva);
 702     }
 703
 704     return dirEntry;
 705   }
 706
 707   bool GetVersionInfo(uint64_t& aOutVersion) const {
 708     // RT_VERSION == 16
 709     // Version resources require an id of 1
 710     auto root = FindResourceLeaf<VS_VERSIONINFO_HEADER*>(16, 1);
 711     if (!root) {
 712       return false;
 713     }
 714
 715     VS_FIXEDFILEINFO* fixedInfo = GetFixedFileInfo(root);
 716     if (!fixedInfo) {
 717       return false;
 718     }
 719
 720     aOutVersion = ((static_cast<uint64_t>(fixedInfo->dwFileVersionMS) << 32) |
 721                    static_cast<uint64_t>(fixedInfo->dwFileVersionLS));
 722     return true;
 723   }
 724
 725   bool GetTimeStamp(DWORD& aResult) const {
 726     if (!(*this)) {
 727       return false;
 728     }
 729
 730     aResult = mPeHeader->FileHeader.TimeDateStamp;
 731     return true;
 732   }
 733
 734   bool GetImageSize(DWORD& aResult) const {
 735     if (!(*this)) {
 736       return false;
 737     }
 738
 739     aResult = mPeHeader->OptionalHeader.SizeOfImage;
 740     return true;
 741   }
 742
 743   bool GetCheckSum(DWORD& aResult) const {
 744     if (!(*this)) {
 745       return false;
 746     }
 747
 748     aResult = mPeHeader->OptionalHeader.CheckSum;
 749     return true;
 750   }
 751
 752   PIMAGE_IMPORT_DESCRIPTOR
 753   GetImportDescriptor(const char* aModuleNameASCII) const {
 754     for (PIMAGE_IMPORT_DESCRIPTOR curImpDesc = GetImportDirectory();
 755          IsValid(curImpDesc); ++curImpDesc) {
 756       auto curName = mIsImportDirectoryTampered
 757                          ? RVAToPtrUnchecked<const char*>(curImpDesc->Name)
 758                          : RVAToPtr<const char*>(curImpDesc->Name);
 759       if (!curName) {
 760         return nullptr;
 761       }
 762
 763       if (StricmpASCII(aModuleNameASCII, curName)) {
 764         continue;
 765       }
 766
 767       // curImpDesc now points to the IAT for the module we're interested in
 768       return curImpDesc;
 769     }
 770
 771     return nullptr;
 772   }
 773
 774   template <typename CallbackT>
 775   void EnumImportChunks(const CallbackT& aCallback) const {
 776     for (PIMAGE_IMPORT_DESCRIPTOR curImpDesc = GetImportDirectory();
 777          IsValid(curImpDesc); ++curImpDesc) {
 778       auto curName = mIsImportDirectoryTampered
 779                          ? RVAToPtrUnchecked<const char*>(curImpDesc->Name)
 780                          : RVAToPtr<const char*>(curImpDesc->Name);
 781       if (!curName) {
 782         continue;
 783       }
 784
 785       aCallback(curName);
 786     }
 787   }
 788
 789   /**
 790    * If |aBoundaries| is given, this method checks whether each IAT entry is
 791    * within the given range, and if any entry is out of the range, we return
 792    * Nothing().
 793    */
 794   Maybe<Span<IMAGE_THUNK_DATA>> GetIATThunksForModule(
 795       const char* aModuleNameASCII,
 796       const Range<const uint8_t>* aBoundaries = nullptr) const {
 797     PIMAGE_IMPORT_DESCRIPTOR impDesc = GetImportDescriptor(aModuleNameASCII);
 798     if (!impDesc) {
 799       return Nothing();
 800     }
 801
 802     auto firstIatThunk =
 803         this->template RVAToPtr<PIMAGE_THUNK_DATA>(impDesc->FirstThunk);
 804     if (!firstIatThunk) {
 805       return Nothing();
 806     }
 807
 808     // Find the length by iterating through the table until we find a null entry
 809     PIMAGE_THUNK_DATA curIatThunk = firstIatThunk;
 810     while (IsValid(curIatThunk)) {
 811       if (aBoundaries) {
 812         auto iatEntry =
 813             reinterpret_cast<const uint8_t*>(curIatThunk->u1.Function);
 814         if (iatEntry < aBoundaries->begin().get() ||
 815             iatEntry >= aBoundaries->end().get()) {
 816           return Nothing();
 817         }
 818       }
 819
 820       ++curIatThunk;
 821     }
 822
 823     return Some(Span(firstIatThunk, curIatThunk));
 824   }
 825
 826   /**
 827    * Resources are stored in a three-level tree. To locate a particular entry,
 828    * you must supply a resource type, the resource id, and then the language id.
 829    * If aLangId == 0, we just resolve the first entry regardless of language.
 830    */
 831   template <typename T>
 832   T FindResourceLeaf(WORD aType, WORD aResId, WORD aLangId = 0) const {
 833     PIMAGE_RESOURCE_DIRECTORY topLevel = GetResourceTable();
 834     if (!topLevel) {
 835       return nullptr;
 836     }
 837
 838     PIMAGE_RESOURCE_DIRECTORY_ENTRY typeEntry =
 839         FindResourceEntry(topLevel, aType);
 840     if (!typeEntry || !typeEntry->DataIsDirectory) {
 841       return nullptr;
 842     }
 843
 844     auto idDir = RVAToPtr<PIMAGE_RESOURCE_DIRECTORY>(
 845         topLevel, typeEntry->OffsetToDirectory);
 846     PIMAGE_RESOURCE_DIRECTORY_ENTRY idEntry = FindResourceEntry(idDir, aResId);
 847     if (!idEntry || !idEntry->DataIsDirectory) {
 848       return nullptr;
 849     }
 850
 851     auto langDir = RVAToPtr<PIMAGE_RESOURCE_DIRECTORY>(
 852         topLevel, idEntry->OffsetToDirectory);
 853     PIMAGE_RESOURCE_DIRECTORY_ENTRY langEntry;
 854     if (aLangId) {
 855       langEntry = FindResourceEntry(langDir, aLangId);
 856     } else {
 857       langEntry = FindFirstResourceEntry(langDir);
 858     }
 859
 860     if (!langEntry || langEntry->DataIsDirectory) {
 861       return nullptr;
 862     }
 863
 864     auto dataEntry =
 865         RVAToPtr<PIMAGE_RESOURCE_DATA_ENTRY>(topLevel, langEntry->OffsetToData);
 866     return dataEntry ? RVAToPtr<T>(dataEntry->OffsetToData) : nullptr;
 867   }
 868
 869   template <size_t N>
 870   Maybe<Span<const uint8_t>> FindSection(const char (&aSecName)[N],
 871                                          DWORD aCharacteristicsMask) const {
 872     static_assert((N - 1) <= IMAGE_SIZEOF_SHORT_NAME,
 873                   "Section names must be at most 8 characters excluding null "
 874                   "terminator");
 875
 876     if (!(*this)) {
 877       return Nothing();
 878     }
 879
 880     Span<IMAGE_SECTION_HEADER> sectionTable = GetSectionTable();
 881     for (auto&& sectionHeader : sectionTable) {
 882       if (strncmp(reinterpret_cast<const char*>(sectionHeader.Name), aSecName,
 883                   IMAGE_SIZEOF_SHORT_NAME)) {
 884         continue;
 885       }
 886
 887       if (!(sectionHeader.Characteristics & aCharacteristicsMask)) {
 888         // We found the section but it does not have the expected
 889         // characteristics
 890         return Nothing();
 891       }
 892
 893       DWORD rva = sectionHeader.VirtualAddress;
 894       if (!rva) {
 895         return Nothing();
 896       }
 897
 898       DWORD size = sectionHeader.Misc.VirtualSize;
 899       if (!size) {
 900         return Nothing();
 901       }
 902
 903       auto base = RVAToPtr<const uint8_t*>(rva);
 904       return Some(Span(base, size));
 905     }
 906
 907     return Nothing();
 908   }
 909
 910   // There may be other code sections in the binary besides .text
 911   Maybe<Span<const uint8_t>> GetTextSectionInfo() const {
 912     return FindSection(".text", IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE |
 913                                     IMAGE_SCN_MEM_READ);
 914   }
 915
 916   static bool IsValid(PIMAGE_IMPORT_DESCRIPTOR aImpDesc) {
 917     return aImpDesc && aImpDesc->OriginalFirstThunk != 0;
 918   }
 919
 920   static bool IsValid(PIMAGE_THUNK_DATA aImgThunk) {
 921     return aImgThunk && aImgThunk->u1.Ordinal != 0;
 922   }
 923
 924   bool IsImportDirectoryTampered() const { return mIsImportDirectoryTampered; }
 925
 926   FARPROC GetEntryPoint() const {
 927     // Use the unchecked version because the entrypoint may be tampered.
 928     return RVAToPtrUnchecked<FARPROC>(
 929         mPeHeader->OptionalHeader.AddressOfEntryPoint);
 930   }
 931
 932   const CodeViewRecord70* GetPdbInfo() const {
 933     PIMAGE_DEBUG_DIRECTORY debugDirectory =
 934         GetImageDirectoryEntry<PIMAGE_DEBUG_DIRECTORY>(
 935             IMAGE_DIRECTORY_ENTRY_DEBUG);
 936     if (!debugDirectory) {
 937       return nullptr;
 938     }
 939
 940     const CodeViewRecord70* debugInfo =
 941         RVAToPtr<CodeViewRecord70*>(debugDirectory->AddressOfRawData);
 942     return (debugInfo && debugInfo->signature == 'SDSR') ? debugInfo : nullptr;
 943   }
 944
 945  private:
 946   enum class BoundsCheckPolicy { Default, Skip };
 947
 948   template <typename T, BoundsCheckPolicy Policy = BoundsCheckPolicy::Default>
 949   T GetImageDirectoryEntry(const uint32_t aDirectoryIndex) const {
 950     PIMAGE_DATA_DIRECTORY dirEntry = GetImageDirectoryEntryPtr(aDirectoryIndex);
 951     if (!dirEntry) {
 952       return nullptr;
 953     }
 954
 955     return Policy == BoundsCheckPolicy::Skip
 956                ? RVAToPtrUnchecked<T>(dirEntry->VirtualAddress)
 957                : RVAToPtr<T>(dirEntry->VirtualAddress);
 958   }
 959
 960   // This private variant does not have bounds checks, because we need to be
 961   // able to resolve the bounds themselves.
 962   template <typename T, typename R>
 963   T RVAToPtrUnchecked(R aRva) const {
 964     return reinterpret_cast<T>(reinterpret_cast<char*>(mMzHeader) + aRva);
 965   }
 966
 967   Span<IMAGE_SECTION_HEADER> GetSectionTable() const {
 968     MOZ_ASSERT(*this);
 969     auto base = RVAToPtr<PIMAGE_SECTION_HEADER>(
 970         &mPeHeader->OptionalHeader, mPeHeader->FileHeader.SizeOfOptionalHeader);
 971     // The Windows loader has an internal limit of 96 sections (per PE spec)
 972     auto numSections =
 973         std::min(mPeHeader->FileHeader.NumberOfSections, WORD(96));
 974     return Span{base, numSections};
 975   }
 976
 977   PIMAGE_RESOURCE_DIRECTORY_ENTRY
 978   FindResourceEntry(PIMAGE_RESOURCE_DIRECTORY aCurLevel, WORD aId) const {
 979     if (!aCurLevel) {
 980       return nullptr;
 981     }
 982
 983     // Immediately after the IMAGE_RESOURCE_DIRECTORY structure is an array
 984     // of IMAGE_RESOURCE_DIRECTORY_ENTRY structures. Since this function
 985     // searches by ID, we need to skip past any named entries before iterating.
 986     auto dirEnt =
 987         reinterpret_cast<PIMAGE_RESOURCE_DIRECTORY_ENTRY>(aCurLevel + 1) +
 988         aCurLevel->NumberOfNamedEntries;
 989     if (!(IsWithinImage(dirEnt) &&
 990           IsWithinImage(&dirEnt[aCurLevel->NumberOfIdEntries - 1].Id))) {
 991       return nullptr;
 992     }
 993
 994     for (WORD i = 0; i < aCurLevel->NumberOfIdEntries; ++i) {
 995       if (dirEnt[i].Id == aId) {
 996         return &dirEnt[i];
 997       }
 998     }
 999
1000     return nullptr;
1001   }
1002
1003   PIMAGE_RESOURCE_DIRECTORY_ENTRY
1004   FindFirstResourceEntry(PIMAGE_RESOURCE_DIRECTORY aCurLevel) const {
1005     // Immediately after the IMAGE_RESOURCE_DIRECTORY structure is an array
1006     // of IMAGE_RESOURCE_DIRECTORY_ENTRY structures. We just return the first
1007     // entry, regardless of whether it is indexed by name or by id.
1008     auto dirEnt =
1009         reinterpret_cast<PIMAGE_RESOURCE_DIRECTORY_ENTRY>(aCurLevel + 1);
1010     WORD numEntries =
1011         aCurLevel->NumberOfNamedEntries + aCurLevel->NumberOfIdEntries;
1012     if (!numEntries) {
1013       return nullptr;
1014     }
1015
1016     return dirEnt;
1017   }
1018
1019   VS_FIXEDFILEINFO* GetFixedFileInfo(VS_VERSIONINFO_HEADER* aVerInfo) const {
1020     WORD length = aVerInfo->wLength;
1021     if (length < sizeof(VS_VERSIONINFO_HEADER)) {
1022       return nullptr;
1023     }
1024
1025     const wchar_t kVersionInfoKey[] = L"VS_VERSION_INFO";
1026     if (::RtlCompareMemory(aVerInfo->szKey, kVersionInfoKey,
1027                            ArrayLength(kVersionInfoKey)) !=
1028         ArrayLength(kVersionInfoKey)) {
1029       return nullptr;
1030     }
1031
1032     if (aVerInfo->wValueLength != sizeof(VS_FIXEDFILEINFO)) {
1033       // Fixed file info does not exist
1034       return nullptr;
1035     }
1036
1037     WORD offset = sizeof(VS_VERSIONINFO_HEADER);
1038
1039     uintptr_t base = reinterpret_cast<uintptr_t>(aVerInfo);
1040     // Align up to 4-byte boundary
1041 #pragma warning(suppress : 4146)
1042     offset += (-(base + offset) & 3);
1043
1044     if (offset >= length) {
1045       return nullptr;
1046     }
1047
1048     auto result = reinterpret_cast<VS_FIXEDFILEINFO*>(base + offset);
1049     if (result->dwSignature != 0xFEEF04BD) {
1050       return nullptr;
1051     }
1052
1053     return result;
1054   }
1055
1056  private:
1057   PIMAGE_DOS_HEADER mMzHeader;
1058   PIMAGE_NT_HEADERS mPeHeader;
1059   void* mImageLimit;
1060   bool mIsImportDirectoryTampered;
1061 };
1062
1063 // This class represents an export section of a local/remote process.
1064 template <typename MMPolicy>
1065 class MOZ_RAII PEExportSection {
1066   const MMPolicy& mMMPolicy;
1067   uintptr_t mImageBase;
1068   DWORD mOrdinalBase;
1069   DWORD mRvaDirStart;
1070   DWORD mRvaDirEnd;
1071   mozilla::interceptor::TargetObjectArray<MMPolicy, DWORD> mExportAddressTable;
1072   mozilla::interceptor::TargetObjectArray<MMPolicy, DWORD> mExportNameTable;
1073   mozilla::interceptor::TargetObjectArray<MMPolicy, WORD> mExportOrdinalTable;
1074
1075   explicit PEExportSection(const MMPolicy& aMMPolicy)
1076       : mMMPolicy(aMMPolicy),
1077         mImageBase(0),
1078         mOrdinalBase(0),
1079         mRvaDirStart(0),
1080         mRvaDirEnd(0),
1081         mExportAddressTable(mMMPolicy),
1082         mExportNameTable(mMMPolicy),
1083         mExportOrdinalTable(mMMPolicy) {}
1084
1085   PEExportSection(const MMPolicy& aMMPolicy, uintptr_t aImageBase,
1086                   DWORD aRvaDirStart, DWORD aRvaDirEnd,
1087                   const IMAGE_EXPORT_DIRECTORY& exportDir)
1088       : mMMPolicy(aMMPolicy),
1089         mImageBase(aImageBase),
1090         mOrdinalBase(exportDir.Base),
1091         mRvaDirStart(aRvaDirStart),
1092         mRvaDirEnd(aRvaDirEnd),
1093         mExportAddressTable(mMMPolicy,
1094                             mImageBase + exportDir.AddressOfFunctions,
1095                             exportDir.NumberOfFunctions),
1096         mExportNameTable(mMMPolicy, mImageBase + exportDir.AddressOfNames,
1097                          exportDir.NumberOfNames),
1098         mExportOrdinalTable(mMMPolicy,
1099                             mImageBase + exportDir.AddressOfNameOrdinals,
1100                             exportDir.NumberOfNames) {}
1101
1102   static const PEExportSection Get(uintptr_t aImageBase,
1103                                    const MMPolicy& aMMPolicy) {
1104     mozilla::interceptor::TargetObject<MMPolicy, IMAGE_DOS_HEADER> mzHeader(
1105         aMMPolicy, aImageBase);
1106     if (!mzHeader || mzHeader->e_magic != IMAGE_DOS_SIGNATURE) {
1107       return PEExportSection(aMMPolicy);
1108     }
1109
1110     mozilla::interceptor::TargetObject<MMPolicy, IMAGE_NT_HEADERS> peHeader(
1111         aMMPolicy, aImageBase + mzHeader->e_lfanew);
1112     if (!peHeader || peHeader->Signature != IMAGE_NT_SIGNATURE) {
1113       return PEExportSection(aMMPolicy);
1114     }
1115
1116     if (peHeader->OptionalHeader.Magic != IMAGE_NT_OPTIONAL_HDR_MAGIC) {
1117       return PEExportSection(aMMPolicy);
1118     }
1119
1120     const IMAGE_OPTIONAL_HEADER& optionalHeader = peHeader->OptionalHeader;
1121
1122     DWORD imageSize = optionalHeader.SizeOfImage;
1123     // This is a coarse-grained check to ensure that the image size is
1124     // reasonable. It we aren't big enough to contain headers, we have a
1125     // problem!
1126     if (imageSize < sizeof(IMAGE_DOS_HEADER) + sizeof(IMAGE_NT_HEADERS)) {
1127       return PEExportSection(aMMPolicy);
1128     }
1129
1130     if (optionalHeader.NumberOfRvaAndSizes <= IMAGE_DIRECTORY_ENTRY_EXPORT) {
1131       return PEExportSection(aMMPolicy);
1132     }
1133
1134     const IMAGE_DATA_DIRECTORY& exportDirectoryEntry =
1135         optionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT];
1136     if (!exportDirectoryEntry.VirtualAddress || !exportDirectoryEntry.Size) {
1137       return PEExportSection(aMMPolicy);
1138     }
1139
1140     mozilla::interceptor::TargetObject<MMPolicy, IMAGE_EXPORT_DIRECTORY>
1141         exportDirectory(aMMPolicy,
1142                         aImageBase + exportDirectoryEntry.VirtualAddress);
1143     if (!exportDirectory || !exportDirectory->NumberOfFunctions) {
1144       return PEExportSection(aMMPolicy);
1145     }
1146
1147     return PEExportSection(
1148         aMMPolicy, aImageBase, exportDirectoryEntry.VirtualAddress,
1149         exportDirectoryEntry.VirtualAddress + exportDirectoryEntry.Size,
1150         *exportDirectory.GetLocalBase());
1151   }
1152
1153   FARPROC GetProcAddressByOrdinal(WORD aOrdinal) const {
1154     if (aOrdinal < mOrdinalBase) {
1155       return nullptr;
1156     }
1157
1158     auto rvaToFunction = mExportAddressTable[aOrdinal - mOrdinalBase];
1159     if (!rvaToFunction) {
1160       return nullptr;
1161     }
1162     return reinterpret_cast<FARPROC>(mImageBase + *rvaToFunction);
1163   }
1164
1165  public:
1166   static const PEExportSection Get(HMODULE aModule, const MMPolicy& aMMPolicy) {
1167     return Get(PEHeaders::HModuleToBaseAddr<uintptr_t>(aModule), aMMPolicy);
1168   }
1169
1170   explicit operator bool() const {
1171     // Because PEExportSection doesn't use MMPolicy::Reserve(), a boolified
1172     // mMMPolicy is expected to be false.  We don't check mMMPolicy here.
1173     return mImageBase && mRvaDirStart && mRvaDirEnd && mExportAddressTable &&
1174            mExportNameTable && mExportOrdinalTable;
1175   }
1176
1177   template <typename T>
1178   T RVAToPtr(uint32_t aRva) const {
1179     return reinterpret_cast<T>(mImageBase + aRva);
1180   }
1181
1182   PIMAGE_EXPORT_DIRECTORY GetExportDirectory() const {
1183     if (!*this) {
1184       return nullptr;
1185     }
1186
1187     return RVAToPtr<PIMAGE_EXPORT_DIRECTORY>(mRvaDirStart);
1188   }
1189
1190   /**
1191    * This functions searches the export table for a given string as
1192    * GetProcAddress does, but this returns a matched entry of the Export
1193    * Address Table i.e. a pointer to an RVA of a matched function instead
1194    * of a function address.  If the entry is forwarded, this function
1195    * returns nullptr.
1196    */
1197   const DWORD* FindExportAddressTableEntry(
1198       const char* aFunctionNameASCII) const {
1199     if (!*this || !aFunctionNameASCII) {
1200       return nullptr;
1201     }
1202
1203     struct NameTableComparator {
1204       NameTableComparator(const PEExportSection<MMPolicy>& aExportSection,
1205                           const char* aTarget)
1206           : mExportSection(aExportSection),
1207             mTargetName(aTarget),
1208             mTargetNamelength(StrlenASCII(aTarget)) {}
1209
1210       int operator()(DWORD aRVAToString) const {
1211         mozilla::interceptor::TargetObjectArray<MMPolicy, char> itemString(
1212             mExportSection.mMMPolicy, mExportSection.mImageBase + aRVAToString,
1213             mTargetNamelength + 1);
1214         return StrcmpASCII(mTargetName, itemString[0]);
1215       }
1216
1217       const PEExportSection<MMPolicy>& mExportSection;
1218       const char* mTargetName;
1219       size_t mTargetNamelength;
1220     };
1221
1222     const NameTableComparator comp(*this, aFunctionNameASCII);
1223
1224     size_t match;
1225     if (!mExportNameTable.BinarySearchIf(comp, &match)) {
1226       return nullptr;
1227     }
1228
1229     const WORD* index = mExportOrdinalTable[match];
1230     if (!index) {
1231       return nullptr;
1232     }
1233
1234     const DWORD* rvaToFunction = mExportAddressTable[*index];
1235     if (!rvaToFunction) {
1236       return nullptr;
1237     }
1238
1239     if (*rvaToFunction >= mRvaDirStart && *rvaToFunction < mRvaDirEnd) {
1240       // If an entry points to an address within the export section, the
1241       // field is a forwarder RVA.  We return nullptr because the entry is
1242       // not a function address but a null-terminated string used for export
1243       // forwarding.
1244       return nullptr;
1245     }
1246
1247     return rvaToFunction;
1248   }
1249
1250   /**
1251    * This functions behaves the same as the native ::GetProcAddress except
1252    * the following cases:
1253    * - Returns nullptr if a target entry is forwarded to another dll.
1254    */
1255   FARPROC GetProcAddress(const char* aFunctionNameASCII) const {
1256     uintptr_t maybeOdrinal = reinterpret_cast<uintptr_t>(aFunctionNameASCII);
1257     // When the high-order word of |aFunctionNameASCII| is zero, it's not
1258     // a string but an ordinal value.
1259     if (maybeOdrinal < 0x10000) {
1260       return GetProcAddressByOrdinal(static_cast<WORD>(maybeOdrinal));
1261     }
1262
1263     auto rvaToFunction = FindExportAddressTableEntry(aFunctionNameASCII);
1264     if (!rvaToFunction) {
1265       return nullptr;
1266     }
1267     return reinterpret_cast<FARPROC>(mImageBase + *rvaToFunction);
1268   }
1269 };
1270
1271 inline HANDLE RtlGetProcessHeap() {
1272   PTEB teb = ::NtCurrentTeb();
1273   PPEB peb = teb->ProcessEnvironmentBlock;
1274   return peb->Reserved4[1];
1275 }
1276
1277 inline PVOID RtlGetThreadLocalStoragePointer() {
1278   return ::NtCurrentTeb()->Reserved1[11];
1279 }
1280
1281 inline void RtlSetThreadLocalStoragePointerForTestingOnly(PVOID aNewValue) {
1282   ::NtCurrentTeb()->Reserved1[11] = aNewValue;
1283 }
1284
1285 inline DWORD RtlGetCurrentThreadId() {
1286   PTEB teb = ::NtCurrentTeb();
1287   CLIENT_ID* cid = reinterpret_cast<CLIENT_ID*>(&teb->Reserved1[8]);
1288   return static_cast<DWORD>(reinterpret_cast<uintptr_t>(cid->UniqueThread) &
1289                             0xFFFFFFFFUL);
1290 }
1291
1292 inline PVOID RtlGetThreadStackBase() {
1293   return reinterpret_cast<_NT_TIB*>(::NtCurrentTeb())->StackBase;
1294 }
1295
1296 inline PVOID RtlGetThreadStackLimit() {
1297   return reinterpret_cast<_NT_TIB*>(::NtCurrentTeb())->StackLimit;
1298 }
1299
1300 const HANDLE kCurrentProcess = reinterpret_cast<HANDLE>(-1);
1301
1302 inline LauncherResult<DWORD> GetParentProcessId() {
1303   struct PROCESS_BASIC_INFORMATION {
1304     NTSTATUS ExitStatus;
1305     PPEB PebBaseAddress;
1306     ULONG_PTR AffinityMask;
1307     LONG BasePriority;
1308     ULONG_PTR UniqueProcessId;
1309     ULONG_PTR InheritedFromUniqueProcessId;
1310   };
1311
1312   ULONG returnLength;
1313   PROCESS_BASIC_INFORMATION pbi = {};
1314   NTSTATUS status =
1315       ::NtQueryInformationProcess(kCurrentProcess, ProcessBasicInformation,
1316                                   &pbi, sizeof(pbi), &returnLength);
1317   if (!NT_SUCCESS(status)) {
1318     return LAUNCHER_ERROR_FROM_NTSTATUS(status);
1319   }
1320
1321   return static_cast<DWORD>(pbi.InheritedFromUniqueProcessId & 0xFFFFFFFF);
1322 }
1323
1324 inline SIZE_T WINAPI VirtualQueryEx(HANDLE aProcess, LPCVOID aAddress,
1325                                     PMEMORY_BASIC_INFORMATION aMemInfo,
1326                                     SIZE_T aMemInfoLen) {
1327 #if defined(MOZILLA_INTERNAL_API)
1328   return ::VirtualQueryEx(aProcess, aAddress, aMemInfo, aMemInfoLen);
1329 #else
1330   SIZE_T returnedLength;
1331   NTSTATUS status = ::NtQueryVirtualMemory(
1332       aProcess, const_cast<PVOID>(aAddress), MemoryBasicInformation, aMemInfo,
1333       aMemInfoLen, &returnedLength);
1334   if (!NT_SUCCESS(status)) {
1335     ::RtlSetLastWin32Error(::RtlNtStatusToDosError(status));
1336     returnedLength = 0;
1337   }
1338   return returnedLength;
1339 #endif  // defined(MOZILLA_INTERNAL_API)
1340 }
1341
1342 inline SIZE_T WINAPI VirtualQuery(LPCVOID aAddress,
1343                                   PMEMORY_BASIC_INFORMATION aMemInfo,
1344                                   SIZE_T aMemInfoLen) {
1345   return nt::VirtualQueryEx(kCurrentProcess, aAddress, aMemInfo, aMemInfoLen);
1346 }
1347
1348 struct DataDirectoryEntry : public _IMAGE_DATA_DIRECTORY {
1349   DataDirectoryEntry() : _IMAGE_DATA_DIRECTORY() {}
1350
1351   MOZ_IMPLICIT DataDirectoryEntry(const _IMAGE_DATA_DIRECTORY& aOther)
1352       : _IMAGE_DATA_DIRECTORY(aOther) {}
1353
1354   DataDirectoryEntry(const DataDirectoryEntry& aOther) = default;
1355
1356   bool operator==(const DataDirectoryEntry& aOther) const {
1357     return VirtualAddress == aOther.VirtualAddress && Size == aOther.Size;
1358   }
1359
1360   bool operator!=(const DataDirectoryEntry& aOther) const {
1361     return !(*this == aOther);
1362   }
1363 };
1364
1365 inline LauncherResult<void*> GetProcessPebPtr(HANDLE aProcess) {
1366   ULONG returnLength;
1367   PROCESS_BASIC_INFORMATION pbi;
1368   NTSTATUS status = ::NtQueryInformationProcess(
1369       aProcess, ProcessBasicInformation, &pbi, sizeof(pbi), &returnLength);
1370   if (!NT_SUCCESS(status)) {
1371     return LAUNCHER_ERROR_FROM_NTSTATUS(status);
1372   }
1373
1374   return pbi.PebBaseAddress;
1375 }
1376
1377 /**
1378  * This function relies on a specific offset into the mostly-undocumented PEB
1379  * structure. The risk is reduced thanks to the fact that the Chromium sandbox
1380  * relies on the location of this field. It is unlikely to change at this point.
1381  * To further reduce the risk, we also check for the magic 'MZ' signature that
1382  * should indicate the beginning of a PE image.
1383  */
1384 inline LauncherResult<HMODULE> GetProcessExeModule(HANDLE aProcess) {
1385   LauncherResult<void*> ppeb = GetProcessPebPtr(aProcess);
1386   if (ppeb.isErr()) {
1387     return ppeb.propagateErr();
1388   }
1389
1390   PEB peb;
1391   SIZE_T bytesRead;
1392
1393 #if defined(MOZILLA_INTERNAL_API)
1394   if (!::ReadProcessMemory(aProcess, ppeb.unwrap(), &peb, sizeof(peb),
1395                            &bytesRead) ||
1396       bytesRead != sizeof(peb)) {
1397     return LAUNCHER_ERROR_FROM_LAST();
1398   }
1399 #else
1400   NTSTATUS ntStatus = ::NtReadVirtualMemory(aProcess, ppeb.unwrap(), &peb,
1401                                             sizeof(peb), &bytesRead);
1402   if (!NT_SUCCESS(ntStatus) || bytesRead != sizeof(peb)) {
1403     return LAUNCHER_ERROR_FROM_NTSTATUS(ntStatus);
1404   }
1405 #endif
1406
1407   // peb.ImageBaseAddress
1408   void* baseAddress = peb.Reserved3[1];
1409
1410   char mzMagic[2];
1411 #if defined(MOZILLA_INTERNAL_API)
1412   if (!::ReadProcessMemory(aProcess, baseAddress, mzMagic, sizeof(mzMagic),
1413                            &bytesRead) ||
1414       bytesRead != sizeof(mzMagic)) {
1415     return LAUNCHER_ERROR_FROM_LAST();
1416   }
1417 #else
1418   ntStatus = ::NtReadVirtualMemory(aProcess, baseAddress, mzMagic,
1419                                    sizeof(mzMagic), &bytesRead);
1420   if (!NT_SUCCESS(ntStatus) || bytesRead != sizeof(mzMagic)) {
1421     return LAUNCHER_ERROR_FROM_NTSTATUS(ntStatus);
1422   }
1423 #endif
1424
1425   MOZ_ASSERT(mzMagic[0] == 'M' && mzMagic[1] == 'Z');
1426   if (mzMagic[0] != 'M' || mzMagic[1] != 'Z') {
1427     return LAUNCHER_ERROR_FROM_WIN32(ERROR_BAD_EXE_FORMAT);
1428   }
1429
1430   return static_cast<HMODULE>(baseAddress);
1431 }
1432
1433 #if defined(_MSC_VER)
1434 extern "C" IMAGE_DOS_HEADER __ImageBase;
1435 #endif
1436
1437 // This class manages data transfer from the local process's executable
1438 // to another process's executable via WriteProcessMemory.
1439 // Bug 1662560 told us the same executable may be mapped onto a different
1440 // address in a different process.  This means when we transfer data within
1441 // the mapped executable such as a global variable or IAT from the current
1442 // process to another process, we need to shift its address by the difference
1443 // between two executable's mapped imagebase.
1444 class CrossExecTransferManager final {
1445   HANDLE mRemoteProcess;
1446   uint8_t* mLocalImagebase;
1447   PEHeaders mLocalExec;
1448   uint8_t* mRemoteImagebase;
1449
1450   static HMODULE GetLocalExecModule() {
1451 #if defined(_MSC_VER)
1452     return reinterpret_cast<HMODULE>(&__ImageBase);
1453 #else
1454     return ::GetModuleHandleW(nullptr);
1455 #endif
1456   }
1457
1458   LauncherVoidResult EnsureRemoteImagebase() {
1459     if (!mRemoteImagebase) {
1460       LauncherResult<HMODULE> remoteImageBaseResult =
1461           GetProcessExeModule(mRemoteProcess);
1462       if (remoteImageBaseResult.isErr()) {
1463         return remoteImageBaseResult.propagateErr();
1464       }
1465
1466       mRemoteImagebase =
1467           reinterpret_cast<uint8_t*>(remoteImageBaseResult.unwrap());
1468     }
1469     return Ok();
1470   }
1471
1472   template <typename T>
1473   T* LocalExecToRemoteExec(T* aLocalAddress) const {
1474     MOZ_ASSERT(mRemoteImagebase);
1475     MOZ_ASSERT(mLocalExec.IsWithinImage(aLocalAddress));
1476
1477     if (!mRemoteImagebase || !mLocalExec.IsWithinImage(aLocalAddress)) {
1478       return aLocalAddress;
1479     }
1480
1481     uintptr_t offset = reinterpret_cast<uintptr_t>(aLocalAddress) -
1482                        reinterpret_cast<uintptr_t>(mLocalImagebase);
1483     return reinterpret_cast<T*>(mRemoteImagebase + offset);
1484   }
1485
1486  public:
1487   explicit CrossExecTransferManager(HANDLE aRemoteProcess)
1488       : mRemoteProcess(aRemoteProcess),
1489         mLocalImagebase(
1490             PEHeaders::HModuleToBaseAddr<uint8_t*>(GetLocalExecModule())),
1491         mLocalExec(mLocalImagebase),
1492         mRemoteImagebase(nullptr) {}
1493
1494   CrossExecTransferManager(HANDLE aRemoteProcess, HMODULE aLocalImagebase)
1495       : mRemoteProcess(aRemoteProcess),
1496         mLocalImagebase(
1497             PEHeaders::HModuleToBaseAddr<uint8_t*>(aLocalImagebase)),
1498         mLocalExec(mLocalImagebase),
1499         mRemoteImagebase(nullptr) {}
1500
1501   explicit operator bool() const { return !!mLocalExec; }
1502   HANDLE RemoteProcess() const { return mRemoteProcess; }
1503   const PEHeaders& LocalPEHeaders() const { return mLocalExec; }
1504
1505   AutoVirtualProtect Protect(void* aLocalAddress, size_t aLength,
1506                              DWORD aProtFlags) {
1507     // If EnsureRemoteImagebase() fails, a subsequent operaion will fail.
1508     Unused << EnsureRemoteImagebase();
1509     return AutoVirtualProtect(LocalExecToRemoteExec(aLocalAddress), aLength,
1510                               aProtFlags, mRemoteProcess);
1511   }
1512
1513   LauncherVoidResult Transfer(LPVOID aDestinationAddress,
1514                               LPCVOID aBufferToWrite, SIZE_T aBufferSize) {
1515     LauncherVoidResult result = EnsureRemoteImagebase();
1516     if (result.isErr()) {
1517       return result.propagateErr();
1518     }
1519
1520     if (!::WriteProcessMemory(mRemoteProcess,
1521                               LocalExecToRemoteExec(aDestinationAddress),
1522                               aBufferToWrite, aBufferSize, nullptr)) {
1523       return LAUNCHER_ERROR_FROM_LAST();
1524     }
1525
1526     return Ok();
1527   }
1528 };
1529
1530 #if !defined(MOZILLA_INTERNAL_API)
1531
1532 inline LauncherResult<HMODULE> GetModuleHandleFromLeafName(
1533     const UNICODE_STRING& aTarget) {
1534   auto maybePeb = nt::GetProcessPebPtr(kCurrentProcess);
1535   if (maybePeb.isErr()) {
1536     return maybePeb.propagateErr();
1537   }
1538
1539   const PPEB peb = reinterpret_cast<PPEB>(maybePeb.unwrap());
1540   if (!peb->Ldr) {
1541     return LAUNCHER_ERROR_FROM_WIN32(ERROR_BAD_EXE_FORMAT);
1542   }
1543
1544   auto firstItem = &peb->Ldr->InMemoryOrderModuleList;
1545   for (auto p = firstItem->Flink; p != firstItem; p = p->Flink) {
1546     const auto currentTableEntry =
1547         CONTAINING_RECORD(p, LDR_DATA_TABLE_ENTRY, InMemoryOrderLinks);
1548
1549     UNICODE_STRING leafName;
1550     nt::GetLeafName(&leafName, &currentTableEntry->FullDllName);
1551
1552     if (::RtlCompareUnicodeString(&leafName, &aTarget, TRUE) == 0) {
1553       return reinterpret_cast<HMODULE>(currentTableEntry->DllBase);
1554     }
1555   }
1556
1557   return LAUNCHER_ERROR_FROM_WIN32(ERROR_MOD_NOT_FOUND);
1558 }
1559
1560 class MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS SRWLock final {
1561  public:
1562   constexpr SRWLock() : mLock(SRWLOCK_INIT) {}
1563
1564   void LockShared() { ::RtlAcquireSRWLockShared(&mLock); }
1565
1566   void LockExclusive() { ::RtlAcquireSRWLockExclusive(&mLock); }
1567
1568   void UnlockShared() { ::RtlReleaseSRWLockShared(&mLock); }
1569
1570   void UnlockExclusive() { ::RtlReleaseSRWLockExclusive(&mLock); }
1571
1572   SRWLock(const SRWLock&) = delete;
1573   SRWLock(SRWLock&&) = delete;
1574   SRWLock& operator=(const SRWLock&) = delete;
1575   SRWLock& operator=(SRWLock&&) = delete;
1576
1577   SRWLOCK* operator&() { return &mLock; }
1578
1579  private:
1580   SRWLOCK mLock;
1581 };
1582
1583 class MOZ_RAII AutoExclusiveLock final {
1584  public:
1585   explicit AutoExclusiveLock(SRWLock& aLock) : mLock(aLock) {
1586     aLock.LockExclusive();
1587   }
1588
1589   ~AutoExclusiveLock() { mLock.UnlockExclusive(); }
1590
1591   AutoExclusiveLock(const AutoExclusiveLock&) = delete;
1592   AutoExclusiveLock(AutoExclusiveLock&&) = delete;
1593   AutoExclusiveLock& operator=(const AutoExclusiveLock&) = delete;
1594   AutoExclusiveLock& operator=(AutoExclusiveLock&&) = delete;
1595
1596  private:
1597   SRWLock& mLock;
1598 };
1599
1600 class MOZ_RAII AutoSharedLock final {
1601  public:
1602   explicit AutoSharedLock(SRWLock& aLock) : mLock(aLock) { aLock.LockShared(); }
1603
1604   ~AutoSharedLock() { mLock.UnlockShared(); }
1605
1606   AutoSharedLock(const AutoSharedLock&) = delete;
1607   AutoSharedLock(AutoSharedLock&&) = delete;
1608   AutoSharedLock& operator=(const AutoSharedLock&) = delete;
1609   AutoSharedLock& operator=(AutoSharedLock&&) = delete;
1610
1611  private:
1612   SRWLock& mLock;
1613 };
1614
1615 #endif  // !defined(MOZILLA_INTERNAL_API)
1616
1617 class RtlAllocPolicy {
1618  public:
1619   template <typename T>
1620   T* maybe_pod_malloc(size_t aNumElems) {
1621     if (aNumElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) {
1622       return nullptr;
1623     }
1624
1625     return static_cast<T*>(
1626         ::RtlAllocateHeap(RtlGetProcessHeap(), 0, aNumElems * sizeof(T)));
1627   }
1628
1629   template <typename T>
1630   T* maybe_pod_calloc(size_t aNumElems) {
1631     if (aNumElems & mozilla::tl::MulOverflowMask<sizeof(T)>::value) {
1632       return nullptr;
1633     }
1634
1635     return static_cast<T*>(::RtlAllocateHeap(
1636         RtlGetProcessHeap(), HEAP_ZERO_MEMORY, aNumElems * sizeof(T)));
1637   }
1638
1639   template <typename T>
1640   T* maybe_pod_realloc(T* aPtr, size_t aOldSize, size_t aNewSize) {
1641     if (aNewSize & mozilla::tl::MulOverflowMask<sizeof(T)>::value) {
1642       return nullptr;
1643     }
1644
1645     return static_cast<T*>(::RtlReAllocateHeap(RtlGetProcessHeap(), 0, aPtr,
1646                                                aNewSize * sizeof(T)));
1647   }
1648
1649   template <typename T>
1650   T* pod_malloc(size_t aNumElems) {
1651     return maybe_pod_malloc<T>(aNumElems);
1652   }
1653
1654   template <typename T>
1655   T* pod_calloc(size_t aNumElems) {
1656     return maybe_pod_calloc<T>(aNumElems);
1657   }
1658
1659   template <typename T>
1660   T* pod_realloc(T* aPtr, size_t aOldSize, size_t aNewSize) {
1661     return maybe_pod_realloc<T>(aPtr, aOldSize, aNewSize);
1662   }
1663
1664   template <typename T>
1665   void free_(T* aPtr, size_t aNumElems = 0) {
1666     ::RtlFreeHeap(RtlGetProcessHeap(), 0, aPtr);
1667   }
1668
1669   void reportAllocOverflow() const {}
1670
1671   [[nodiscard]] bool checkSimulatedOOM() const { return true; }
1672 };
1673
1674 class AutoMappedView final {
1675   void* mView;
1676
1677   void Unmap() {
1678     if (!mView) {
1679       return;
1680     }
1681
1682 #if defined(MOZILLA_INTERNAL_API)
1683     ::UnmapViewOfFile(mView);
1684 #else
1685     NTSTATUS status = ::NtUnmapViewOfSection(nt::kCurrentProcess, mView);
1686     if (!NT_SUCCESS(status)) {
1687       ::RtlSetLastWin32Error(::RtlNtStatusToDosError(status));
1688     }
1689 #endif
1690     mView = nullptr;
1691   }
1692
1693  public:
1694   explicit AutoMappedView(void* aView) : mView(aView) {}
1695
1696   AutoMappedView(HANDLE aSection, ULONG aProtectionFlags) : mView(nullptr) {
1697 #if defined(MOZILLA_INTERNAL_API)
1698     mView = ::MapViewOfFile(aSection, aProtectionFlags, 0, 0, 0);
1699 #else
1700     SIZE_T viewSize = 0;
1701     NTSTATUS status = ::NtMapViewOfSection(aSection, nt::kCurrentProcess,
1702                                            &mView, 0, 0, nullptr, &viewSize,
1703                                            ViewUnmap, 0, aProtectionFlags);
1704     if (!NT_SUCCESS(status)) {
1705       ::RtlSetLastWin32Error(::RtlNtStatusToDosError(status));
1706     }
1707 #endif
1708   }
1709   ~AutoMappedView() { Unmap(); }
1710
1711   // Allow move & Disallow copy
1712   AutoMappedView(AutoMappedView&& aOther) : mView(aOther.mView) {
1713     aOther.mView = nullptr;
1714   }
1715   AutoMappedView& operator=(AutoMappedView&& aOther) {
1716     if (this != &aOther) {
1717       Unmap();
1718       mView = aOther.mView;
1719       aOther.mView = nullptr;
1720     }
1721     return *this;
1722   }
1723   AutoMappedView(const AutoMappedView&) = delete;
1724   AutoMappedView& operator=(const AutoMappedView&) = delete;
1725
1726   explicit operator bool() const { return !!mView; }
1727   template <typename T>
1728   T* as() {
1729     return reinterpret_cast<T*>(mView);
1730   }
1731
1732   void* release() {
1733     void* p = mView;
1734     mView = nullptr;
1735     return p;
1736   }
1737 };
1738
1739 #if defined(_M_X64)
1740 // CheckStack ensures that stack memory pages are committed up to a given size
1741 // in bytes from the current stack pointer. It updates the thread stack limit,
1742 // which points to the lowest committed stack address.
1743 MOZ_NEVER_INLINE MOZ_NAKED inline void CheckStack(uint32_t size) {
1744   asm volatile(
1745       "mov %ecx, %eax;"
1746 #  if defined(__MINGW32__)
1747       "jmp ___chkstk_ms;"
1748 #  else
1749       "jmp __chkstk;"
1750 #  endif  // __MINGW32__
1751   );
1752 }
1753 #endif  // _M_X64
1754
1755 }  // namespace nt
1756 }  // namespace mozilla
1757
1758 #endif  // mozilla_NativeNt_h