Move the Windows sandbox to sandbox/win

sandbox/src/interception_agent.cc

-// Copyright (c) 2006-2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// For information about interceptions as a whole see
-// http://dev.chromium.org/developers/design-documents/sandbox .
-
-#include "sandbox/src/interception_agent.h"
-
-#include "sandbox/src/interception_internal.h"
-#include "sandbox/src/interceptors.h"
-#include "sandbox/src/eat_resolver.h"
-#include "sandbox/src/sidestep_resolver.h"
-#include "sandbox/src/sandbox_nt_util.h"
-
-namespace {
-
-// Returns true if target lies between base and base + range.
-bool IsWithinRange(const void* base, size_t range, const void* target) {
-  const char* end = reinterpret_cast<const char*>(base) + range;
-  return reinterpret_cast<const char*>(target) < end;
-}
-
-}  // namespace
-
-namespace sandbox {
-
-// This is the list of all imported symbols from ntdll.dll.
-SANDBOX_INTERCEPT NtExports g_nt;
-
-// The list of intercepted functions back-pointers.
-SANDBOX_INTERCEPT OriginalFunctions g_originals;
-
-// Memory buffer mapped from the parent, with the list of interceptions.
-SANDBOX_INTERCEPT SharedMemory* g_interceptions = NULL;
-
-InterceptionAgent* InterceptionAgent::GetInterceptionAgent() {
-  static InterceptionAgent* s_singleton = NULL;
-  if (!s_singleton) {
-    if (!g_interceptions)
-      return NULL;
-
-    size_t array_bytes = g_interceptions->num_intercepted_dlls * sizeof(void*);
-    s_singleton = reinterpret_cast<InterceptionAgent*>(
-        new(NT_ALLOC) char[array_bytes + sizeof(InterceptionAgent)]);
-
-    bool success = s_singleton->Init(g_interceptions);
-    if (!success) {
-      operator delete(s_singleton, NT_ALLOC);
-      s_singleton = NULL;
-    }
-  }
-  return s_singleton;
-}
-
-bool InterceptionAgent::Init(SharedMemory* shared_memory) {
-  interceptions_ = shared_memory;
-  for (int i = 0 ; i < shared_memory->num_intercepted_dlls; i++)
-    dlls_[i] = NULL;
-  return true;
-}
-
-bool InterceptionAgent::DllMatch(const UNICODE_STRING* full_path,
-                                 const UNICODE_STRING* name,
-                                 const DllPatchInfo* dll_info) {
-  UNICODE_STRING current_name;
-  current_name.Length = static_cast<USHORT>(g_nt.wcslen(dll_info->dll_name) *
-                                            sizeof(wchar_t));
-  current_name.MaximumLength = current_name.Length;
-  current_name.Buffer = const_cast<wchar_t*>(dll_info->dll_name);
-
-  BOOLEAN case_insensitive = TRUE;
-  if (full_path &&
-      !g_nt.RtlCompareUnicodeString(&current_name, full_path, case_insensitive))
-    return true;
-
-  if (name &&
-      !g_nt.RtlCompareUnicodeString(&current_name, name, case_insensitive))
-    return true;
-
-  return false;
-}
-
-bool InterceptionAgent::OnDllLoad(const UNICODE_STRING* full_path,
-                                  const UNICODE_STRING* name,
-                                  void* base_address) {
-  DllPatchInfo* dll_info = interceptions_->dll_list;
-  int i = 0;
-  for (; i < interceptions_->num_intercepted_dlls; i++) {
-    if (DllMatch(full_path, name, dll_info))
-      break;
-
-    dll_info = reinterpret_cast<DllPatchInfo*>(
-                   reinterpret_cast<char*>(dll_info) + dll_info->record_bytes);
-  }
-
-  // Return now if the dll is not in our list of interest.
-  if (i == interceptions_->num_intercepted_dlls)
-    return true;
-
-  // The dll must be unloaded.
-  if (dll_info->unload_module)
-    return false;
-
-  // Purify causes this condition to trigger.
-  if (dlls_[i])
-    return true;
-
-  size_t buffer_bytes = offsetof(DllInterceptionData, thunks) +
-                        dll_info->num_functions * sizeof(ThunkData);
-  dlls_[i] = reinterpret_cast<DllInterceptionData*>(
-                 new(NT_PAGE, base_address) char[buffer_bytes]);
-
-  DCHECK_NT(dlls_[i]);
-  if (!dlls_[i])
-    return true;
-
-  dlls_[i]->data_bytes = buffer_bytes;
-  dlls_[i]->num_thunks = 0;
-  dlls_[i]->base = base_address;
-  dlls_[i]->used_bytes = offsetof(DllInterceptionData, thunks);
-
-  VERIFY(PatchDll(dll_info, dlls_[i]));
-
-  ULONG old_protect;
-  SIZE_T real_size = buffer_bytes;
-  void* to_protect = dlls_[i];
-  VERIFY_SUCCESS(g_nt.ProtectVirtualMemory(NtCurrentProcess, &to_protect,
-                                           &real_size, PAGE_EXECUTE_READ,
-                                           &old_protect));
-  return true;
-}
-
-void InterceptionAgent::OnDllUnload(void* base_address) {
-  for (int i = 0; i < interceptions_->num_intercepted_dlls; i++) {
-    if (dlls_[i] && dlls_[i]->base == base_address) {
-      operator delete(dlls_[i], NT_PAGE);
-      dlls_[i] = NULL;
-      break;
-    }
-  }
-}
-
-// TODO(rvargas): We have to deal with prebinded dlls. I see two options: change
-// the timestamp of the patched dll, or modify the info on the prebinded dll.
-// the first approach messes matching of debug symbols, the second one is more
-// complicated.
-bool InterceptionAgent::PatchDll(const DllPatchInfo* dll_info,
-                                 DllInterceptionData* thunks) {
-  DCHECK_NT(NULL != thunks);
-  DCHECK_NT(NULL != dll_info);
-
-  const FunctionInfo* function = reinterpret_cast<const FunctionInfo*>(
-      reinterpret_cast<const char*>(dll_info) + dll_info->offset_to_functions);
-
-  for (int i = 0; i < dll_info->num_functions; i++) {
-    if (!IsWithinRange(dll_info, dll_info->record_bytes, function->function)) {
-      NOTREACHED_NT();
-      return false;
-    }
-
-    ResolverThunk* resolver = GetResolver(function->type);
-    if (!resolver)
-      return false;
-
-    const char* interceptor = function->function +
-                              g_nt.strlen(function->function) + 1;
-
-    if (!IsWithinRange(function, function->record_bytes, interceptor) ||
-        !IsWithinRange(dll_info, dll_info->record_bytes, interceptor)) {
-      NOTREACHED_NT();
-      return false;
-    }
-
-    NTSTATUS ret = resolver->Setup(thunks->base,
-                                   interceptions_->interceptor_base,
-                                   function->function,
-                                   interceptor,
-                                   function->interceptor_address,
-                                   &thunks->thunks[i],
-                                   sizeof(ThunkData),
-                                   NULL);
-    if (!NT_SUCCESS(ret)) {
-      NOTREACHED_NT();
-      return false;
-    }
-
-    DCHECK_NT(!g_originals[function->id]);
-    g_originals[function->id] = &thunks->thunks[i];
-
-    thunks->num_thunks++;
-    thunks->used_bytes += sizeof(ThunkData);
-
-    function = reinterpret_cast<const FunctionInfo*>(
-        reinterpret_cast<const char*>(function) + function->record_bytes);
-  }
-
-  return true;
-}
-
-// This method is called from within the loader lock
-ResolverThunk* InterceptionAgent::GetResolver(InterceptionType type) {
-  static EatResolverThunk* eat_resolver = NULL;
-  static SidestepResolverThunk* sidestep_resolver = NULL;
-  static SmartSidestepResolverThunk* smart_sidestep_resolver = NULL;
-
-  if (!eat_resolver)
-    eat_resolver = new(NT_ALLOC) EatResolverThunk;
-
-#if !defined(_WIN64)
-  // Sidestep is not supported for x64.
-  if (!sidestep_resolver)
-    sidestep_resolver = new(NT_ALLOC) SidestepResolverThunk;
-
-  if (!smart_sidestep_resolver)
-    smart_sidestep_resolver = new(NT_ALLOC) SmartSidestepResolverThunk;
-#endif
-
-  switch (type) {
-    case INTERCEPTION_EAT:
-      return eat_resolver;
-    case INTERCEPTION_SIDESTEP:
-      return sidestep_resolver;
-    case INTERCEPTION_SMART_SIDESTEP:
-      return smart_sidestep_resolver;
-    default:
-      NOTREACHED_NT();
-  }
-
-  return NULL;
-}
-
-}  // namespace sandbox