Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1189 insertions, 0 deletions

diff --git a/modules/libjar/nsZipArchive.cpp b/modules/libjar/nsZipArchive.cpp
new file mode 100644
index 0000000000..1f43a0d625
--- /dev/null
+++ b/modules/libjar/nsZipArchive.cpp
@@ -0,0 +1,1189 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+/*
+ * This module implements a simple archive extractor for the PKZIP format.
+ */
+
+#define READTYPE int32_t
+#include "zlib.h"
+#include "nsISupportsUtils.h"
+#include "mozilla/MmapFaultHandler.h"
+#include "prio.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Logging.h"
+#include "mozilla/MemUtils.h"
+#include "mozilla/UniquePtrExtensions.h"
+#include "mozilla/StaticMutex.h"
+#include "stdlib.h"
+#include "nsDirectoryService.h"
+#include "nsWildCard.h"
+#include "nsXULAppAPI.h"
+#include "nsZipArchive.h"
+#include "nsString.h"
+#include "prenv.h"
+#if defined(XP_WIN)
+#  include <windows.h>
+#endif
+
+// For placement new used for arena allocations of zip file list
+#include <new>
+#define ZIP_ARENABLOCKSIZE (1 * 1024)
+
+#ifdef XP_UNIX
+#  include <sys/mman.h>
+#  include <sys/types.h>
+#  include <sys/stat.h>
+#  include <limits.h>
+#  include <unistd.h>
+#elif defined(XP_WIN)
+#  include <io.h>
+#endif
+
+#ifdef __SYMBIAN32__
+#  include <sys/syslimits.h>
+#endif /*__SYMBIAN32__*/
+
+#ifndef XP_UNIX /* we need some constants defined in limits.h and unistd.h */
+#  ifndef S_IFMT
+#    define S_IFMT 0170000
+#  endif
+#  ifndef S_IFLNK
+#    define S_IFLNK 0120000
+#  endif
+#  ifndef PATH_MAX
+#    define PATH_MAX 1024
+#  endif
+#endif /* XP_UNIX */
+
+#ifdef XP_WIN
+#  include "private/pprio.h"  // To get PR_ImportFile
+#endif
+
+using namespace mozilla;
+
+static LazyLogModule gZipLog("nsZipArchive");
+
+#ifdef LOG
+#  undef LOG
+#endif
+#ifdef LOG_ENABLED
+#  undef LOG_ENABLED
+#endif
+
+#define LOG(args) MOZ_LOG(gZipLog, mozilla::LogLevel::Debug, args)
+#define LOG_ENABLED() MOZ_LOG_TEST(gZipLog, mozilla::LogLevel::Debug)
+
+static const uint32_t kMaxNameLength = PATH_MAX; /* Maximum name length */
+// For synthetic zip entries. Date/time corresponds to 1980-01-01 00:00.
+static const uint16_t kSyntheticTime = 0;
+static const uint16_t kSyntheticDate = (1 + (1 << 5) + (0 << 9));
+
+static uint16_t xtoint(const uint8_t* ii);
+static uint32_t xtolong(const uint8_t* ll);
+static uint32_t HashName(const char* aName, uint16_t nameLen);
+
+class ZipArchiveLogger {
+ public:
+  void Init(const char* env) {
+    StaticMutexAutoLock lock(sLock);
+
+    // AddRef
+    MOZ_ASSERT(mRefCnt >= 0);
+    ++mRefCnt;
+
+    if (!mFd) {
+      nsCOMPtr<nsIFile> logFile;
+      nsresult rv = NS_NewLocalFile(NS_ConvertUTF8toUTF16(env), false,
+                                    getter_AddRefs(logFile));
+      if (NS_FAILED(rv)) return;
+
+      // Create the log file and its parent directory (in case it doesn't exist)
+      rv = logFile->Create(nsIFile::NORMAL_FILE_TYPE, 0644);
+      if (NS_FAILED(rv)) return;
+
+      PRFileDesc* file;
+#ifdef XP_WIN
+      // PR_APPEND is racy on Windows, so open a handle ourselves with flags
+      // that will work, and use PR_ImportFile to make it a PRFileDesc. This can
+      // go away when bug 840435 is fixed.
+      nsAutoString path;
+      logFile->GetPath(path);
+      if (path.IsEmpty()) return;
+      HANDLE handle =
+          CreateFileW(path.get(), FILE_APPEND_DATA, FILE_SHARE_WRITE, nullptr,
+                      OPEN_ALWAYS, 0, nullptr);
+      if (handle == INVALID_HANDLE_VALUE) return;
+      file = PR_ImportFile((PROsfd)handle);
+      if (!file) return;
+#else
+      rv = logFile->OpenNSPRFileDesc(
+          PR_WRONLY | PR_CREATE_FILE | PR_APPEND | PR_SYNC, 0644, &file);
+      if (NS_FAILED(rv)) return;
+#endif
+      mFd = file;
+    }
+  }
+
+  void Write(const nsACString& zip, const char* entry) {
+    StaticMutexAutoLock lock(sLock);
+
+    if (mFd) {
+      nsCString buf(zip);
+      buf.Append(' ');
+      buf.Append(entry);
+      buf.Append('\n');
+      PR_Write(mFd, buf.get(), buf.Length());
+    }
+  }
+
+  void Release() {
+    StaticMutexAutoLock lock(sLock);
+
+    MOZ_ASSERT(mRefCnt > 0);
+    if ((0 == --mRefCnt) && mFd) {
+      PR_Close(mFd);
+      mFd = nullptr;
+    }
+  }
+
+ private:
+  static StaticMutex sLock;
+  int mRefCnt MOZ_GUARDED_BY(sLock);
+  PRFileDesc* mFd MOZ_GUARDED_BY(sLock);
+};
+
+StaticMutex ZipArchiveLogger::sLock;
+static ZipArchiveLogger zipLog;
+
+//***********************************************************
+// For every inflation the following allocations are done:
+// malloc(1 * 9520)
+// malloc(32768 * 1)
+//***********************************************************
+
+nsresult gZlibInit(z_stream* zs) {
+  memset(zs, 0, sizeof(z_stream));
+  int zerr = inflateInit2(zs, -MAX_WBITS);
+  if (zerr != Z_OK) return NS_ERROR_OUT_OF_MEMORY;
+
+  return NS_OK;
+}
+
+nsZipHandle::nsZipHandle()
+    : mFileData(nullptr),
+      mLen(0),
+      mMap(nullptr),
+      mRefCnt(0),
+      mFileStart(nullptr),
+      mTotalLen(0) {}
+
+NS_IMPL_ADDREF(nsZipHandle)
+NS_IMPL_RELEASE(nsZipHandle)
+
+nsresult nsZipHandle::Init(nsIFile* file, nsZipHandle** ret, PRFileDesc** aFd) {
+  mozilla::AutoFDClose fd;
+  int32_t flags = PR_RDONLY;
+#if defined(XP_WIN)
+  flags |= nsIFile::OS_READAHEAD;
+#endif
+  LOG(("ZipHandle::Init %s", file->HumanReadablePath().get()));
+  nsresult rv = file->OpenNSPRFileDesc(flags, 0000, &fd.rwget());
+  if (NS_FAILED(rv)) return rv;
+
+  int64_t size = PR_Available64(fd);
+  if (size >= INT32_MAX) return NS_ERROR_FILE_TOO_BIG;
+
+  PRFileMap* map = PR_CreateFileMap(fd, size, PR_PROT_READONLY);
+  if (!map) return NS_ERROR_FAILURE;
+
+  uint8_t* buf = (uint8_t*)PR_MemMap(map, 0, (uint32_t)size);
+  // Bug 525755: PR_MemMap fails when fd points at something other than a normal
+  // file.
+  if (!buf) {
+    PR_CloseFileMap(map);
+    return NS_ERROR_FAILURE;
+  }
+
+  RefPtr<nsZipHandle> handle = new nsZipHandle();
+  if (!handle) {
+    PR_MemUnmap(buf, (uint32_t)size);
+    PR_CloseFileMap(map);
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+#if defined(XP_WIN)
+  if (aFd) {
+    *aFd = fd.forget();
+  }
+#else
+  handle->mNSPRFileDesc = fd.forget();
+#endif
+  handle->mFile.Init(file);
+  handle->mTotalLen = (uint32_t)size;
+  handle->mFileStart = buf;
+  rv = handle->findDataStart();
+  if (NS_FAILED(rv)) {
+    PR_MemUnmap(buf, (uint32_t)size);
+    handle->mFileStart = nullptr;
+    PR_CloseFileMap(map);
+    return rv;
+  }
+  handle->mMap = map;
+  handle.forget(ret);
+  return NS_OK;
+}
+
+nsresult nsZipHandle::Init(nsZipArchive* zip, const char* entry,
+                           nsZipHandle** ret) {
+  RefPtr<nsZipHandle> handle = new nsZipHandle();
+  if (!handle) return NS_ERROR_OUT_OF_MEMORY;
+
+  LOG(("ZipHandle::Init entry %s", entry));
+  handle->mBuf = MakeUnique<nsZipItemPtr<uint8_t>>(zip, entry);
+  if (!handle->mBuf) return NS_ERROR_OUT_OF_MEMORY;
+
+  if (!handle->mBuf->Buffer()) return NS_ERROR_UNEXPECTED;
+
+  handle->mMap = nullptr;
+  handle->mFile.Init(zip, entry);
+  handle->mTotalLen = handle->mBuf->Length();
+  handle->mFileStart = handle->mBuf->Buffer();
+  nsresult rv = handle->findDataStart();
+  if (NS_FAILED(rv)) {
+    return rv;
+  }
+  handle.forget(ret);
+  return NS_OK;
+}
+
+// This function finds the start of the ZIP data. If the file is a regular ZIP,
+// this is just the start of the file. If the file is a CRX file, the start of
+// the data is after the CRX header.
+// CRX header reference: (CRX version 2)
+//    Header requires little-endian byte ordering with 4-byte alignment.
+//    32 bits       : magicNumber   - Defined as a |char m[] = "Cr24"|.
+//                                    Equivilant to |uint32_t m = 0x34327243|.
+//    32 bits       : version       - Unsigned integer representing the CRX file
+//                                    format version. Currently equal to 2.
+//    32 bits       : pubKeyLength  - Unsigned integer representing the length
+//                                    of the public key in bytes.
+//    32 bits       : sigLength     - Unsigned integer representing the length
+//                                    of the signature in bytes.
+//    pubKeyLength  : publicKey     - Contents of the author's public key.
+//    sigLength     : signature     - Signature of the ZIP content.
+//                                    Signature is created using the RSA
+//                                    algorithm with the SHA-1 hash function.
+nsresult nsZipHandle::findDataStart() {
+  // In the CRX header, integers are 32 bits. Our pointer to the file is of
+  // type |uint8_t|, which is guaranteed to be 8 bits.
+  const uint32_t CRXIntSize = 4;
+
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(this)
+  if (mTotalLen > CRXIntSize * 4 && xtolong(mFileStart) == kCRXMagic) {
+    const uint8_t* headerData = mFileStart;
+    headerData += CRXIntSize * 2;  // Skip magic number and version number
+    uint32_t pubKeyLength = xtolong(headerData);
+    headerData += CRXIntSize;
+    uint32_t sigLength = xtolong(headerData);
+    uint32_t headerSize = CRXIntSize * 4 + pubKeyLength + sigLength;
+    if (mTotalLen > headerSize) {
+      mLen = mTotalLen - headerSize;
+      mFileData = mFileStart + headerSize;
+      return NS_OK;
+    }
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+  mLen = mTotalLen;
+  mFileData = mFileStart;
+  MMAP_FAULT_HANDLER_CATCH(NS_ERROR_FAILURE)
+  return NS_OK;
+}
+
+int64_t nsZipHandle::SizeOfMapping() { return mTotalLen; }
+
+nsresult nsZipHandle::GetNSPRFileDesc(PRFileDesc** aNSPRFileDesc) {
+  if (!aNSPRFileDesc) {
+    return NS_ERROR_ILLEGAL_VALUE;
+  }
+
+  *aNSPRFileDesc = mNSPRFileDesc;
+  if (!mNSPRFileDesc) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  return NS_OK;
+}
+
+nsZipHandle::~nsZipHandle() {
+  if (mMap) {
+    PR_MemUnmap((void*)mFileStart, mTotalLen);
+    PR_CloseFileMap(mMap);
+  }
+  mFileStart = nullptr;
+  mFileData = nullptr;
+  mMap = nullptr;
+  mBuf = nullptr;
+}
+
+//***********************************************************
+//      nsZipArchive  --  public methods
+//***********************************************************
+
+//---------------------------------------------
+//  nsZipArchive::OpenArchive
+//---------------------------------------------
+/* static */
+already_AddRefed<nsZipArchive> nsZipArchive::OpenArchive(
+    nsZipHandle* aZipHandle, PRFileDesc* aFd) {
+  nsresult rv;
+  RefPtr<nsZipArchive> self(new nsZipArchive(aZipHandle, aFd, rv));
+  LOG(("ZipHandle::OpenArchive[%p]", self.get()));
+  if (NS_FAILED(rv)) {
+    self = nullptr;
+  }
+  return self.forget();
+}
+
+/* static */
+already_AddRefed<nsZipArchive> nsZipArchive::OpenArchive(nsIFile* aFile) {
+  RefPtr<nsZipHandle> handle;
+#if defined(XP_WIN)
+  mozilla::AutoFDClose fd;
+  nsresult rv = nsZipHandle::Init(aFile, getter_AddRefs(handle), &fd.rwget());
+#else
+  nsresult rv = nsZipHandle::Init(aFile, getter_AddRefs(handle));
+#endif
+  if (NS_FAILED(rv)) return nullptr;
+
+#if defined(XP_WIN)
+  return OpenArchive(handle, fd.get());
+#else
+  return OpenArchive(handle);
+#endif
+}
+
+//---------------------------------------------
+//  nsZipArchive::Test
+//---------------------------------------------
+nsresult nsZipArchive::Test(const char* aEntryName) {
+  nsZipItem* currItem;
+
+  if (aEntryName)  // only test specified item
+  {
+    currItem = GetItem(aEntryName);
+    if (!currItem) return NS_ERROR_FILE_NOT_FOUND;
+    //-- don't test (synthetic) directory items
+    if (currItem->IsDirectory()) return NS_OK;
+    return ExtractFile(currItem, 0, 0);
+  }
+
+  // test all items in archive
+  for (auto* item : mFiles) {
+    for (currItem = item; currItem; currItem = currItem->next) {
+      //-- don't test (synthetic) directory items
+      if (currItem->IsDirectory()) continue;
+      nsresult rv = ExtractFile(currItem, 0, 0);
+      if (rv != NS_OK) return rv;
+    }
+  }
+
+  return NS_OK;
+}
+
+//---------------------------------------------
+// nsZipArchive::GetItem
+//---------------------------------------------
+nsZipItem* nsZipArchive::GetItem(const char* aEntryName) {
+  MutexAutoLock lock(mLock);
+
+  LOG(("ZipHandle::GetItem[%p] %s", this, aEntryName));
+  if (aEntryName) {
+    uint32_t len = strlen(aEntryName);
+    //-- If the request is for a directory, make sure that synthetic entries
+    //-- are created for the directories without their own entry.
+    if (!mBuiltSynthetics) {
+      if ((len > 0) && (aEntryName[len - 1] == '/')) {
+        if (BuildSynthetics() != NS_OK) return 0;
+      }
+    }
+    MMAP_FAULT_HANDLER_BEGIN_HANDLE(mFd)
+    nsZipItem* item = mFiles[HashName(aEntryName, len)];
+    while (item) {
+      if ((len == item->nameLength) &&
+          (!memcmp(aEntryName, item->Name(), len))) {
+        // Successful GetItem() is a good indicator that the file is about to be
+        // read
+        if (mUseZipLog && mURI.Length()) {
+          zipLog.Write(mURI, aEntryName);
+        }
+        return item;  //-- found it
+      }
+      item = item->next;
+    }
+    MMAP_FAULT_HANDLER_CATCH(nullptr)
+  }
+  return nullptr;
+}
+
+//---------------------------------------------
+// nsZipArchive::ExtractFile
+// This extracts the item to the filehandle provided.
+// If 'aFd' is null, it only tests the extraction.
+// On extraction error(s) it removes the file.
+//---------------------------------------------
+nsresult nsZipArchive::ExtractFile(nsZipItem* item, nsIFile* outFile,
+                                   PRFileDesc* aFd) {
+  MutexAutoLock lock(mLock);
+  LOG(("ZipHandle::ExtractFile[%p]", this));
+  if (!item) return NS_ERROR_ILLEGAL_VALUE;
+  if (!mFd) return NS_ERROR_FAILURE;
+
+  // Directory extraction is handled in nsJAR::Extract,
+  // so the item to be extracted should never be a directory
+  MOZ_ASSERT(!item->IsDirectory());
+
+  Bytef outbuf[ZIP_BUFLEN];
+
+  nsZipCursor cursor(item, this, outbuf, ZIP_BUFLEN, true);
+
+  nsresult rv = NS_OK;
+
+  while (true) {
+    uint32_t count = 0;
+    uint8_t* buf = cursor.Read(&count);
+    if (!buf) {
+      rv = NS_ERROR_FILE_CORRUPTED;
+      break;
+    }
+    if (count == 0) {
+      break;
+    }
+
+    if (aFd && PR_Write(aFd, buf, count) < (READTYPE)count) {
+      rv = NS_ERROR_FILE_NO_DEVICE_SPACE;
+      break;
+    }
+  }
+
+  //-- delete the file on errors
+  if (aFd) {
+    PR_Close(aFd);
+    if (NS_FAILED(rv) && outFile) {
+      outFile->Remove(false);
+    }
+  }
+
+  return rv;
+}
+
+//---------------------------------------------
+// nsZipArchive::FindInit
+//---------------------------------------------
+nsresult nsZipArchive::FindInit(const char* aPattern, nsZipFind** aFind) {
+  if (!aFind) return NS_ERROR_ILLEGAL_VALUE;
+
+  MutexAutoLock lock(mLock);
+
+  LOG(("ZipHandle::FindInit[%p]", this));
+  // null out param in case an error happens
+  *aFind = nullptr;
+
+  bool regExp = false;
+  char* pattern = 0;
+
+  // Create synthetic directory entries on demand
+  nsresult rv = BuildSynthetics();
+  if (rv != NS_OK) return rv;
+
+  // validate the pattern
+  if (aPattern) {
+    switch (NS_WildCardValid((char*)aPattern)) {
+      case INVALID_SXP:
+        return NS_ERROR_ILLEGAL_VALUE;
+
+      case NON_SXP:
+        regExp = false;
+        break;
+
+      case VALID_SXP:
+        regExp = true;
+        break;
+
+      default:
+        // undocumented return value from RegExpValid!
+        MOZ_ASSERT(false);
+        return NS_ERROR_ILLEGAL_VALUE;
+    }
+
+    pattern = strdup(aPattern);
+    if (!pattern) return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  *aFind = new nsZipFind(this, pattern, regExp);
+  if (!*aFind) {
+    free(pattern);
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+
+  return NS_OK;
+}
+
+//---------------------------------------------
+// nsZipFind::FindNext
+//---------------------------------------------
+nsresult nsZipFind::FindNext(const char** aResult, uint16_t* aNameLen) {
+  if (!mArchive || !aResult || !aNameLen) return NS_ERROR_ILLEGAL_VALUE;
+
+  MutexAutoLock lock(mArchive->mLock);
+  *aResult = 0;
+  *aNameLen = 0;
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(mArchive->GetFD())
+  // we start from last match, look for next
+  while (mSlot < ZIP_TABSIZE) {
+    // move to next in current chain, or move to new slot
+    mItem = mItem ? mItem->next : mArchive->mFiles[mSlot];
+
+    bool found = false;
+    if (!mItem)
+      ++mSlot;  // no more in this chain, move to next slot
+    else if (!mPattern)
+      found = true;  // always match
+    else if (mRegExp) {
+      char buf[kMaxNameLength + 1];
+      memcpy(buf, mItem->Name(), mItem->nameLength);
+      buf[mItem->nameLength] = '\0';
+      found = (NS_WildCardMatch(buf, mPattern, false) == MATCH);
+    } else
+      found = ((mItem->nameLength == strlen(mPattern)) &&
+               (memcmp(mItem->Name(), mPattern, mItem->nameLength) == 0));
+    if (found) {
+      // Need also to return the name length, as it is NOT zero-terminatdd...
+      *aResult = mItem->Name();
+      *aNameLen = mItem->nameLength;
+      LOG(("ZipHandle::FindNext[%p] %s", this, *aResult));
+      return NS_OK;
+    }
+  }
+  MMAP_FAULT_HANDLER_CATCH(NS_ERROR_FAILURE)
+  LOG(("ZipHandle::FindNext[%p] not found %s", this, mPattern));
+  return NS_ERROR_FILE_NOT_FOUND;
+}
+
+//***********************************************************
+//      nsZipArchive  --  private implementation
+//***********************************************************
+
+//---------------------------------------------
+//  nsZipArchive::CreateZipItem
+//---------------------------------------------
+nsZipItem* nsZipArchive::CreateZipItem() {
+  // Arena allocate the nsZipItem
+  return (nsZipItem*)mArena.Allocate(sizeof(nsZipItem), mozilla::fallible);
+}
+
+//---------------------------------------------
+//  nsZipArchive::BuildFileList
+//---------------------------------------------
+nsresult nsZipArchive::BuildFileList(PRFileDesc* aFd)
+    MOZ_NO_THREAD_SAFETY_ANALYSIS {
+  // We're only called from the constructor, but need to call
+  // CreateZipItem(), which touches locked data, and modify mFiles.  Turn
+  // off thread-safety, which normally doesn't apply for constructors
+  // anyways
+
+  // Get archive size using end pos
+  const uint8_t* buf;
+  const uint8_t* startp = mFd->mFileData;
+  const uint8_t* endp = startp + mFd->mLen;
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(mFd)
+  uint32_t centralOffset = 4;
+  LOG(("ZipHandle::BuildFileList[%p]", this));
+  // Only perform readahead in the parent process. Children processes
+  // don't need readahead when the file has already been readahead by
+  // the parent process, and readahead only really happens for omni.ja,
+  // which is used in the parent process.
+  if (XRE_IsParentProcess() && mFd->mLen > ZIPCENTRAL_SIZE &&
+      xtolong(startp + centralOffset) == CENTRALSIG) {
+    // Success means optimized jar layout from bug 559961 is in effect
+    uint32_t readaheadLength = xtolong(startp);
+    mozilla::PrefetchMemory(const_cast<uint8_t*>(startp), readaheadLength);
+  } else {
+    for (buf = endp - ZIPEND_SIZE; buf > startp; buf--) {
+      if (xtolong(buf) == ENDSIG) {
+        centralOffset = xtolong(((ZipEnd*)buf)->offset_central_dir);
+        break;
+      }
+    }
+  }
+
+  if (!centralOffset) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  buf = startp + centralOffset;
+
+  // avoid overflow of startp + centralOffset.
+  if (buf < startp) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  //-- Read the central directory headers
+  uint32_t sig = 0;
+  while ((buf + int32_t(sizeof(uint32_t)) > buf) &&
+         (buf + int32_t(sizeof(uint32_t)) <= endp) &&
+         ((sig = xtolong(buf)) == CENTRALSIG)) {
+    // Make sure there is enough data available.
+    if ((buf > endp) || (endp - buf < ZIPCENTRAL_SIZE)) {
+      return NS_ERROR_FILE_CORRUPTED;
+    }
+
+    // Read the fixed-size data.
+    ZipCentral* central = (ZipCentral*)buf;
+
+    uint16_t namelen = xtoint(central->filename_len);
+    uint16_t extralen = xtoint(central->extrafield_len);
+    uint16_t commentlen = xtoint(central->commentfield_len);
+    uint32_t diff = ZIPCENTRAL_SIZE + namelen + extralen + commentlen;
+
+    // Sanity check variable sizes and refuse to deal with
+    // anything too big: it's likely a corrupt archive.
+    if (namelen < 1 || namelen > kMaxNameLength) {
+      return NS_ERROR_FILE_CORRUPTED;
+    }
+    if (buf >= buf + diff ||  // No overflow
+        buf >= endp - diff) {
+      return NS_ERROR_FILE_CORRUPTED;
+    }
+
+    // Point to the next item at the top of loop
+    buf += diff;
+
+    nsZipItem* item = CreateZipItem();
+    if (!item) return NS_ERROR_OUT_OF_MEMORY;
+
+    item->central = central;
+    item->nameLength = namelen;
+    item->isSynthetic = false;
+
+    // Add item to file table
+#ifdef DEBUG
+    nsDependentCSubstring name(item->Name(), namelen);
+    LOG(("   %s", PromiseFlatCString(name).get()));
+#endif
+    uint32_t hash = HashName(item->Name(), namelen);
+    item->next = mFiles[hash];
+    mFiles[hash] = item;
+
+    sig = 0;
+  } /* while reading central directory records */
+
+  if (sig != ENDSIG) {
+    return NS_ERROR_FILE_CORRUPTED;
+  }
+
+  MMAP_FAULT_HANDLER_CATCH(NS_ERROR_FAILURE)
+  return NS_OK;
+}
+
+//---------------------------------------------
+//  nsZipArchive::BuildSynthetics
+//---------------------------------------------
+nsresult nsZipArchive::BuildSynthetics() {
+  mLock.AssertCurrentThreadOwns();
+
+  if (mBuiltSynthetics) return NS_OK;
+  mBuiltSynthetics = true;
+
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(mFd)
+  // Create synthetic entries for any missing directories.
+  // Do this when all ziptable has scanned to prevent double entries.
+  for (auto* item : mFiles) {
+    for (; item != nullptr; item = item->next) {
+      if (item->isSynthetic) continue;
+
+      //-- add entries for directories in the current item's path
+      //-- go from end to beginning, because then we can stop trying
+      //-- to create diritems if we find that the diritem we want to
+      //-- create already exists
+      //-- start just before the last char so as to not add the item
+      //-- twice if it's a directory
+      uint16_t namelen = item->nameLength;
+      MOZ_ASSERT(namelen > 0,
+                 "Attempt to build synthetic for zero-length entry name!");
+      const char* name = item->Name();
+      for (uint16_t dirlen = namelen - 1; dirlen > 0; dirlen--) {
+        if (name[dirlen - 1] != '/') continue;
+
+        // The character before this is '/', so if this is also '/' then we
+        // have an empty path component. Skip it.
+        if (name[dirlen] == '/') continue;
+
+        // Is the directory already in the file table?
+        uint32_t hash = HashName(item->Name(), dirlen);
+        bool found = false;
+        for (nsZipItem* zi = mFiles[hash]; zi != nullptr; zi = zi->next) {
+          if ((dirlen == zi->nameLength) &&
+              (0 == memcmp(item->Name(), zi->Name(), dirlen))) {
+            // we've already added this dir and all its parents
+            found = true;
+            break;
+          }
+        }
+        // if the directory was found, break out of the directory
+        // creation loop now that we know all implicit directories
+        // are there -- otherwise, start creating the zip item
+        if (found) break;
+
+        nsZipItem* diritem = CreateZipItem();
+        if (!diritem) return NS_ERROR_OUT_OF_MEMORY;
+
+        // Point to the central record of the original item for the name part.
+        diritem->central = item->central;
+        diritem->nameLength = dirlen;
+        diritem->isSynthetic = true;
+
+        // add diritem to the file table
+        diritem->next = mFiles[hash];
+        mFiles[hash] = diritem;
+      } /* end processing of dirs in item's name */
+    }
+  }
+  MMAP_FAULT_HANDLER_CATCH(NS_ERROR_FAILURE)
+  return NS_OK;
+}
+
+//---------------------------------------------
+// nsZipArchive::GetFD
+//---------------------------------------------
+nsZipHandle* nsZipArchive::GetFD() const { return mFd.get(); }
+
+//---------------------------------------------
+// nsZipArchive::GetDataOffset
+// Returns 0 on an error; 0 is not a valid result for any success case
+//---------------------------------------------
+uint32_t nsZipArchive::GetDataOffset(nsZipItem* aItem) {
+  MOZ_ASSERT(aItem);
+  MOZ_DIAGNOSTIC_ASSERT(mFd);
+
+  uint32_t offset;
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(mFd)
+  //-- read local header to get variable length values and calculate
+  //-- the real data offset
+  uint32_t len = mFd->mLen;
+  MOZ_DIAGNOSTIC_ASSERT(len <= UINT32_MAX, "mLen > 2GB");
+  const uint8_t* data = mFd->mFileData;
+  offset = aItem->LocalOffset();
+  if (len < ZIPLOCAL_SIZE || offset > len - ZIPLOCAL_SIZE) {
+    return 0;
+  }
+  // Check there's enough space for the signature
+  if (offset > mFd->mLen) {
+    NS_WARNING("Corrupt local offset in JAR file");
+    return 0;
+  }
+
+  // -- check signature before using the structure, in case the zip file is
+  // corrupt
+  ZipLocal* Local = (ZipLocal*)(data + offset);
+  if ((xtolong(Local->signature) != LOCALSIG)) return 0;
+
+  //-- NOTE: extralen is different in central header and local header
+  //--       for archives created using the Unix "zip" utility. To set
+  //--       the offset accurately we need the _local_ extralen.
+  offset += ZIPLOCAL_SIZE + xtoint(Local->filename_len) +
+            xtoint(Local->extrafield_len);
+  // Check data points inside the file.
+  if (offset > mFd->mLen) {
+    NS_WARNING("Corrupt data offset in JAR file");
+    return 0;
+  }
+
+  MMAP_FAULT_HANDLER_CATCH(0)
+  // can't be 0
+  return offset;
+}
+
+//---------------------------------------------
+// nsZipArchive::GetData
+//---------------------------------------------
+const uint8_t* nsZipArchive::GetData(nsZipItem* aItem) {
+  MOZ_DIAGNOSTIC_ASSERT(aItem);
+  if (!aItem) {
+    return nullptr;
+  }
+  uint32_t offset = GetDataOffset(aItem);
+
+  MMAP_FAULT_HANDLER_BEGIN_HANDLE(mFd)
+  // -- check if there is enough source data in the file
+  if (!offset || mFd->mLen < aItem->Size() ||
+      offset > mFd->mLen - aItem->Size() ||
+      (aItem->Compression() == STORED && aItem->Size() != aItem->RealSize())) {
+    return nullptr;
+  }
+  MMAP_FAULT_HANDLER_CATCH(nullptr)
+
+  return mFd->mFileData + offset;
+}
+
+//---------------------------------------------
+// nsZipArchive::SizeOfMapping
+//---------------------------------------------
+int64_t nsZipArchive::SizeOfMapping() { return mFd ? mFd->SizeOfMapping() : 0; }
+
+//------------------------------------------
+// nsZipArchive constructor and destructor
+//------------------------------------------
+
+nsZipArchive::nsZipArchive(nsZipHandle* aZipHandle, PRFileDesc* aFd,
+                           nsresult& aRv)
+    : mRefCnt(0), mFd(aZipHandle), mUseZipLog(false), mBuiltSynthetics(false) {
+  // initialize the table to nullptr
+  memset(mFiles, 0, sizeof(mFiles));
+  MOZ_DIAGNOSTIC_ASSERT(aZipHandle);
+
+  //-- get table of contents for archive
+  aRv = BuildFileList(aFd);
+  if (NS_FAILED(aRv)) {
+    return;  // whomever created us must destroy us in this case
+  }
+  if (aZipHandle->mFile && XRE_IsParentProcess()) {
+    static char* env = PR_GetEnv("MOZ_JAR_LOG_FILE");
+    if (env) {
+      mUseZipLog = true;
+
+      zipLog.Init(env);
+      // We only log accesses in jar/zip archives within the NS_GRE_DIR
+      // and/or the APK on Android. For the former, we log the archive path
+      // relative to NS_GRE_DIR, and for the latter, the nested-archive
+      // path within the APK. This makes the path match the path of the
+      // archives relative to the packaged dist/$APP_NAME directory in a
+      // build.
+      if (aZipHandle->mFile.IsZip()) {
+        // Nested archive, likely omni.ja in APK.
+        aZipHandle->mFile.GetPath(mURI);
+      } else if (nsDirectoryService::gService) {
+        // We can reach here through the initialization of Omnijar from
+        // XRE_InitCommandLine, which happens before the directory service
+        // is initialized. When that happens, it means the opened archive is
+        // the APK, and we don't care to log that one, so we just skip
+        // when the directory service is not initialized.
+        nsCOMPtr<nsIFile> dir = aZipHandle->mFile.GetBaseFile();
+        nsCOMPtr<nsIFile> gre_dir;
+        nsAutoCString path;
+        if (NS_SUCCEEDED(nsDirectoryService::gService->Get(
+                NS_GRE_DIR, NS_GET_IID(nsIFile), getter_AddRefs(gre_dir)))) {
+          nsAutoCString leaf;
+          nsCOMPtr<nsIFile> parent;
+          while (NS_SUCCEEDED(dir->GetNativeLeafName(leaf)) &&
+                 NS_SUCCEEDED(dir->GetParent(getter_AddRefs(parent)))) {
+            if (!parent) {
+              break;
+            }
+            dir = parent;
+            if (path.Length()) {
+              path.Insert('/', 0);
+            }
+            path.Insert(leaf, 0);
+            bool equals;
+            if (NS_SUCCEEDED(dir->Equals(gre_dir, &equals)) && equals) {
+              mURI.Assign(path);
+              break;
+            }
+          }
+        }
+      }
+    }
+  }
+}
+
+NS_IMPL_ADDREF(nsZipArchive)
+NS_IMPL_RELEASE(nsZipArchive)
+
+nsZipArchive::~nsZipArchive() {
+  LOG(("Closing nsZipArchive[%p]", this));
+  if (mUseZipLog) {
+    zipLog.Release();
+  }
+}
+
+//------------------------------------------
+// nsZipFind constructor and destructor
+//------------------------------------------
+
+nsZipFind::nsZipFind(nsZipArchive* aZip, char* aPattern, bool aRegExp)
+    : mArchive(aZip),
+      mPattern(aPattern),
+      mItem(nullptr),
+      mSlot(0),
+      mRegExp(aRegExp) {
+  MOZ_COUNT_CTOR(nsZipFind);
+}
+
+nsZipFind::~nsZipFind() {
+  free(mPattern);
+
+  MOZ_COUNT_DTOR(nsZipFind);
+}
+
+//------------------------------------------
+// helper functions
+//------------------------------------------
+
+/*
+ * HashName
+ *
+ * returns a hash key for the entry name
+ */
+MOZ_NO_SANITIZE_UNSIGNED_OVERFLOW
+static uint32_t HashName(const char* aName, uint16_t len) {
+  MOZ_ASSERT(aName != 0);
+
+  const uint8_t* p = (const uint8_t*)aName;
+  const uint8_t* endp = p + len;
+  uint32_t val = 0;
+  while (p != endp) {
+    val = val * 37 + *p++;
+  }
+
+  return (val % ZIP_TABSIZE);
+}
+
+/*
+ *  x t o i n t
+ *
+ *  Converts a two byte ugly endianed integer
+ *  to our platform's integer.
+ */
+static uint16_t xtoint(const uint8_t* ii) {
+  return (uint16_t)((ii[0]) | (ii[1] << 8));
+}
+
+/*
+ *  x t o l o n g
+ *
+ *  Converts a four byte ugly endianed integer
+ *  to our platform's integer.
+ */
+static uint32_t xtolong(const uint8_t* ll) {
+  return (uint32_t)((ll[0] << 0) | (ll[1] << 8) | (ll[2] << 16) |
+                    (ll[3] << 24));
+}
+
+/*
+ * GetModTime
+ *
+ * returns last modification time in microseconds
+ */
+static PRTime GetModTime(uint16_t aDate, uint16_t aTime) {
+  // Note that on DST shift we can't handle correctly the hour that is valid
+  // in both DST zones
+  PRExplodedTime time;
+
+  time.tm_usec = 0;
+
+  time.tm_hour = (aTime >> 11) & 0x1F;
+  time.tm_min = (aTime >> 5) & 0x3F;
+  time.tm_sec = (aTime & 0x1F) * 2;
+
+  time.tm_year = (aDate >> 9) + 1980;
+  time.tm_month = ((aDate >> 5) & 0x0F) - 1;
+  time.tm_mday = aDate & 0x1F;
+
+  time.tm_params.tp_gmt_offset = 0;
+  time.tm_params.tp_dst_offset = 0;
+
+  PR_NormalizeTime(&time, PR_GMTParameters);
+  time.tm_params.tp_gmt_offset = PR_LocalTimeParameters(&time).tp_gmt_offset;
+  PR_NormalizeTime(&time, PR_GMTParameters);
+  time.tm_params.tp_dst_offset = PR_LocalTimeParameters(&time).tp_dst_offset;
+
+  return PR_ImplodeTime(&time);
+}
+
+nsZipItem::nsZipItem()
+    : next(nullptr), central(nullptr), nameLength(0), isSynthetic(false) {}
+
+uint32_t nsZipItem::LocalOffset() { return xtolong(central->localhdr_offset); }
+
+uint32_t nsZipItem::Size() { return isSynthetic ? 0 : xtolong(central->size); }
+
+uint32_t nsZipItem::RealSize() {
+  return isSynthetic ? 0 : xtolong(central->orglen);
+}
+
+uint32_t nsZipItem::CRC32() {
+  return isSynthetic ? 0 : xtolong(central->crc32);
+}
+
+uint16_t nsZipItem::Date() {
+  return isSynthetic ? kSyntheticDate : xtoint(central->date);
+}
+
+uint16_t nsZipItem::Time() {
+  return isSynthetic ? kSyntheticTime : xtoint(central->time);
+}
+
+uint16_t nsZipItem::Compression() {
+  return isSynthetic ? STORED : xtoint(central->method);
+}
+
+bool nsZipItem::IsDirectory() {
+  return isSynthetic || ((nameLength > 0) && ('/' == Name()[nameLength - 1]));
+}
+
+uint16_t nsZipItem::Mode() {
+  if (isSynthetic) return 0755;
+  return ((uint16_t)(central->external_attributes[2]) | 0x100);
+}
+
+const uint8_t* nsZipItem::GetExtraField(uint16_t aTag, uint16_t* aBlockSize) {
+  if (isSynthetic) return nullptr;
+
+  const unsigned char* buf =
+      ((const unsigned char*)central) + ZIPCENTRAL_SIZE + nameLength;
+  uint32_t buflen;
+
+  MMAP_FAULT_HANDLER_BEGIN_BUFFER(central, ZIPCENTRAL_SIZE + nameLength)
+  buflen = (uint32_t)xtoint(central->extrafield_len);
+  MMAP_FAULT_HANDLER_CATCH(nullptr)
+
+  uint32_t pos = 0;
+  uint16_t tag, blocksize;
+
+  MMAP_FAULT_HANDLER_BEGIN_BUFFER(buf, buflen)
+  while (buf && (pos + 4) <= buflen) {
+    tag = xtoint(buf + pos);
+    blocksize = xtoint(buf + pos + 2);
+
+    if (aTag == tag && (pos + 4 + blocksize) <= buflen) {
+      *aBlockSize = blocksize;
+      return buf + pos;
+    }
+
+    pos += blocksize + 4;
+  }
+  MMAP_FAULT_HANDLER_CATCH(nullptr)
+
+  return nullptr;
+}
+
+PRTime nsZipItem::LastModTime() {
+  if (isSynthetic) return GetModTime(kSyntheticDate, kSyntheticTime);
+
+  // Try to read timestamp from extra field
+  uint16_t blocksize;
+  const uint8_t* tsField = GetExtraField(EXTENDED_TIMESTAMP_FIELD, &blocksize);
+  if (tsField && blocksize >= 5 && tsField[4] & EXTENDED_TIMESTAMP_MODTIME) {
+    return (PRTime)(xtolong(tsField + 5)) * PR_USEC_PER_SEC;
+  }
+
+  return GetModTime(Date(), Time());
+}
+
+nsZipCursor::nsZipCursor(nsZipItem* item, nsZipArchive* aZip, uint8_t* aBuf,
+                         uint32_t aBufSize, bool doCRC)
+    : mItem(item),
+      mBuf(aBuf),
+      mBufSize(aBufSize),
+      mZs(),
+      mCRC(0),
+      mDoCRC(doCRC) {
+  if (mItem->Compression() == DEFLATED) {
+#ifdef DEBUG
+    nsresult status =
+#endif
+        gZlibInit(&mZs);
+    NS_ASSERTION(status == NS_OK, "Zlib failed to initialize");
+    NS_ASSERTION(aBuf, "Must pass in a buffer for DEFLATED nsZipItem");
+  }
+
+  mZs.avail_in = item->Size();
+  mZs.next_in = (Bytef*)aZip->GetData(item);
+
+  if (doCRC) mCRC = crc32(0L, Z_NULL, 0);
+}
+
+nsZipCursor::~nsZipCursor() {
+  if (mItem->Compression() == DEFLATED) {
+    inflateEnd(&mZs);
+  }
+}
+
+uint8_t* nsZipCursor::ReadOrCopy(uint32_t* aBytesRead, bool aCopy) {
+  int zerr;
+  uint8_t* buf = nullptr;
+  bool verifyCRC = true;
+
+  if (!mZs.next_in) return nullptr;
+  MMAP_FAULT_HANDLER_BEGIN_BUFFER(mZs.next_in, mZs.avail_in)
+  switch (mItem->Compression()) {
+    case STORED:
+      if (!aCopy) {
+        *aBytesRead = mZs.avail_in;
+        buf = mZs.next_in;
+        mZs.next_in += mZs.avail_in;
+        mZs.avail_in = 0;
+      } else {
+        *aBytesRead = mZs.avail_in > mBufSize ? mBufSize : mZs.avail_in;
+        memcpy(mBuf, mZs.next_in, *aBytesRead);
+        mZs.avail_in -= *aBytesRead;
+        mZs.next_in += *aBytesRead;
+      }
+      break;
+    case DEFLATED:
+      buf = mBuf;
+      mZs.next_out = buf;
+      mZs.avail_out = mBufSize;
+
+      zerr = inflate(&mZs, Z_PARTIAL_FLUSH);
+      if (zerr != Z_OK && zerr != Z_STREAM_END) return nullptr;
+
+      *aBytesRead = mZs.next_out - buf;
+      verifyCRC = (zerr == Z_STREAM_END);
+      break;
+    default:
+      return nullptr;
+  }
+
+  if (mDoCRC) {
+    mCRC = crc32(mCRC, (const unsigned char*)buf, *aBytesRead);
+    if (verifyCRC && mCRC != mItem->CRC32()) return nullptr;
+  }
+  MMAP_FAULT_HANDLER_CATCH(nullptr)
+  return buf;
+}
+
+nsZipItemPtr_base::nsZipItemPtr_base(nsZipArchive* aZip, const char* aEntryName,
+                                     bool doCRC)
+    : mReturnBuf(nullptr), mReadlen(0) {
+  // make sure the ziparchive hangs around
+  mZipHandle = aZip->GetFD();
+
+  nsZipItem* item = aZip->GetItem(aEntryName);
+  if (!item) return;
+
+  uint32_t size = 0;
+  bool compressed = (item->Compression() == DEFLATED);
+  if (compressed) {
+    size = item->RealSize();
+    mAutoBuf = MakeUniqueFallible<uint8_t[]>(size);
+    if (!mAutoBuf) {
+      return;
+    }
+  }
+
+  nsZipCursor cursor(item, aZip, mAutoBuf.get(), size, doCRC);
+  mReturnBuf = cursor.Read(&mReadlen);
+  if (!mReturnBuf) {
+    return;
+  }
+
+  if (mReadlen != item->RealSize()) {
+    NS_ASSERTION(mReadlen == item->RealSize(), "nsZipCursor underflow");
+    mReturnBuf = nullptr;
+    return;
+  }
+}