Revert 255151 "Make chrome_elf use thunks instead of function po..."

trunk/src/chrome_elf/ntdll_cache.cc

Index: trunk/src/chrome_elf/ntdll_cache.cc
===================================================================
--- trunk/src/chrome_elf/ntdll_cache.cc	(revision 255702)
+++ trunk/src/chrome_elf/ntdll_cache.cc	(working copy)
@@ -2,26 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome_elf/ntdll_cache.h"
-
 #include <stdint.h>
 #include <windows.h>
 
-#include "base/basictypes.h"
-#include "chrome_elf/thunk_getter.h"
-#include "sandbox/win/src/interception_internal.h"
-#include "sandbox/win/src/internal_types.h"
-#include "sandbox/win/src/service_resolver.h"
+#include "chrome_elf/ntdll_cache.h"
 
-// Allocate storage for thunks in a page of this module to save on doing
-// an extra allocation at run time.
-#pragma section(".crthunk", read, execute)
-__declspec(allocate(".crthunk")) sandbox::ThunkData g_nt_thunk_storage;
-
 FunctionLookupTable g_ntdll_lookup;
 
 void InitCache() {
-  HMODULE ntdll_handle = ::GetModuleHandle(sandbox::kNtdllName);
+  HMODULE ntdll_handle = ::GetModuleHandle(L"ntdll.dll");
 
   // To find the Export Address Table address, we start from the DOS header.
   // The module handle is actually the address of the header.
@@ -59,43 +48,4 @@
     FARPROC func_addr = reinterpret_cast<FARPROC>(func + base_addr);
     g_ntdll_lookup[std::string(name)] = func_addr;
   }
-
-  const bool kRelaxed = true;
-
-  // Create a thunk via the appropriate ServiceResolver instance.
-  sandbox::ServiceResolverThunk* thunk = GetThunk(kRelaxed);
-
-  if (thunk) {
-    BYTE* thunk_storage = reinterpret_cast<BYTE*>(&g_nt_thunk_storage);
-
-    // Mark the thunk storage as readable and writeable, since we
-    // ready to write to it.
-    DWORD old_protect = 0;
-    if (!::VirtualProtect(&g_nt_thunk_storage,
-                          sizeof(g_nt_thunk_storage),
-                          PAGE_EXECUTE_READWRITE,
-                          &old_protect)) {
-      return;
-    }
-
-    size_t storage_used = 0;
-    NTSTATUS ret = thunk->CopyThunk(::GetModuleHandle(sandbox::kNtdllName),
-                                    "NtCreateFile",
-                                    thunk_storage,
-                                    sizeof(sandbox::ThunkData),
-                                    &storage_used);
-    delete thunk;
-
-    // Ensure that the pointer to the old function can't be changed.
-    ::VirtualProtect(&g_nt_thunk_storage,
-                     sizeof(g_nt_thunk_storage),
-                     PAGE_EXECUTE_READ,
-                     &old_protect);
-
-    if (NT_SUCCESS(ret)) {
-      // Add an entry in the lookup table for the thunk.
-      g_ntdll_lookup["NtCreateFile"] =
-          reinterpret_cast<FARPROC>(&g_nt_thunk_storage);
-    }
-  }
 }