gecko-dev/toolkit/xre/nsWindowsDllBlocklist.cpp
2010-08-06 14:06:28 -07:00

229 lines
7.1 KiB
C++

/* -*- Mode: C++; tab-width: 40; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
* Mozilla Corp
* Portions created by the Initial Developer are Copyright (C) 2009
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Vladimir Vukicevic <vladimir@pobox.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <windows.h>
#include <winternl.h>
#include <stdio.h>
#include "nsAutoPtr.h"
#include "prlog.h"
#include "nsWindowsDllInterceptor.h"
#define IN_WINDOWS_DLL_BLOCKLIST
#include "nsWindowsDllBlocklist.h"
#ifndef STATUS_DLL_NOT_FOUND
#define STATUS_DLL_NOT_FOUND ((DWORD)0xC0000135L)
#endif
// define this for very verbose dll load debug spew
#undef DEBUG_very_verbose
// The signature for LdrLoadDll changed at some point, with the second arg
// becoming a PULONG instead of a ULONG. This should only matter on 64-bit
// systems, for which there was no support earlier -- on 32-bit systems,
// they should be the same size.
PR_STATIC_ASSERT(sizeof(PULONG) == sizeof(ULONG));
typedef NTSTATUS (NTAPI *LdrLoadDll_func) (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileName, PHANDLE handle);
static LdrLoadDll_func stub_LdrLoadDll = 0;
static NTSTATUS NTAPI
patched_LdrLoadDll (PWCHAR filePath, PULONG flags, PUNICODE_STRING moduleFileName, PHANDLE handle)
{
// We have UCS2 (UTF16?), we want ASCII, but we also just want the filename portion
#define DLLNAME_MAX 128
char dllName[DLLNAME_MAX+1];
int len = moduleFileName->Length / 2;
wchar_t *fname = moduleFileName->Buffer;
// The filename isn't guaranteed to be null terminated, but in practice
// it always will be; ensure that this is so, and bail if not.
// This is done instead of the more robust approach because of bug 527122,
// where lots of weird things were happening when we tried to make a copy.
if (moduleFileName->MaximumLength < moduleFileName->Length+2 ||
fname[len] != 0)
{
#ifdef DEBUG
printf_stderr("LdrLoadDll: non-null terminated string found!\n");
#endif
goto continue_loading;
}
wchar_t *dll_part = wcsrchr(fname, L'\\');
if (dll_part) {
dll_part = dll_part + 1;
len -= dll_part - fname;
} else {
dll_part = fname;
}
#ifdef DEBUG_very_verbose
printf_stderr("LdrLoadDll: dll_part '%S' %d\n", dll_part, len);
#endif
// if it's too long, then, we assume we won't want to block it,
// since DLLNAME_MAX should be at least long enough to hold the longest
// entry in our blocklist.
if (len > DLLNAME_MAX) {
#ifdef DEBUG
printf_stderr("LdrLoadDll: len too long! %d\n", len);
#endif
goto continue_loading;
}
// copy over to our char byte buffer, lowercasing ASCII as we go
for (int i = 0; i < len; i++) {
wchar_t c = dll_part[i];
if (c > 0x7f) {
// welp, it's not ascii; if we need to add non-ascii things to
// our blocklist, we'll have to remove this limitation.
goto continue_loading;
}
// ensure that dll name is all lowercase
if (c >= 'A' && c <= 'Z')
c += 'a' - 'A';
dllName[i] = (char) c;
}
dllName[len] = 0;
#ifdef DEBUG_very_verbose
printf_stderr("LdrLoadDll: dll name '%s'\n", dllName);
#endif
// then compare to everything on the blocklist
DllBlockInfo *info = &sWindowsDllBlocklist[0];
while (info->name) {
if (strcmp(info->name, dllName) == 0)
break;
info++;
}
if (info->name) {
bool load_ok = false;
#ifdef DEBUG_very_verbose
printf_stderr("LdrLoadDll: info->name: '%s'\n", info->name);
#endif
if (info->maxVersion != ALL_VERSIONS) {
// figure out the length of the string that we need
DWORD pathlen = SearchPathW(filePath, fname, L".dll", 0, NULL, NULL);
if (pathlen == 0) {
// uh, we couldn't find the DLL at all, so...
printf_stderr("LdrLoadDll: Blocking load of '%s' (SearchPathW didn't find it?)\n", dllName);
return STATUS_DLL_NOT_FOUND;
}
wchar_t *full_fname = (wchar_t*) malloc(sizeof(wchar_t)*(pathlen+1));
if (!full_fname) {
// couldn't allocate memory?
return STATUS_DLL_NOT_FOUND;
}
// now actually grab it
SearchPathW(filePath, fname, L".dll", pathlen+1, full_fname, NULL);
DWORD zero;
DWORD infoSize = GetFileVersionInfoSizeW(full_fname, &zero);
// If we failed to get the version information, we block.
if (infoSize != 0) {
nsAutoArrayPtr<unsigned char> infoData = new unsigned char[infoSize];
VS_FIXEDFILEINFO *vInfo;
UINT vInfoLen;
if (GetFileVersionInfoW(full_fname, 0, infoSize, infoData) &&
VerQueryValueW(infoData, L"\\", (LPVOID*) &vInfo, &vInfoLen))
{
unsigned long long fVersion =
((unsigned long long)vInfo->dwFileVersionMS) << 32 |
((unsigned long long)vInfo->dwFileVersionLS);
// finally do the version check, and if it's greater than our block
// version, keep loading
if (fVersion > info->maxVersion)
load_ok = true;
}
}
free(full_fname);
}
if (!load_ok) {
printf_stderr("LdrLoadDll: Blocking load of '%s' -- see http://www.mozilla.com/en-US/blocklist/\n", dllName);
return STATUS_DLL_NOT_FOUND;
}
}
continue_loading:
#ifdef DEBUG_very_verbose
printf_stderr("LdrLoadDll: continuing load... ('%S')\n", moduleFileName->Buffer);
#endif
NS_SetHasLoadedNewDLLs();
return stub_LdrLoadDll(filePath, flags, moduleFileName, handle);
}
WindowsDllInterceptor NtDllIntercept;
void
SetupDllBlocklist()
{
NtDllIntercept.Init("ntdll.dll");
bool ok = NtDllIntercept.AddHook("LdrLoadDll", patched_LdrLoadDll, (void**) &stub_LdrLoadDll);
#ifdef DEBUG
if (!ok)
printf_stderr ("LdrLoadDll hook failed, no dll blocklisting active\n");
#endif
}