michael@0: // Copyright (c) 2011 The Chromium Authors. All rights reserved.
michael@0: // Use of this source code is governed by a BSD-style license that can be
michael@0: // found in the LICENSE file.
michael@0: 
michael@0: #include "sandbox/win/src/handle_closer.h"
michael@0: 
michael@0: #include "base/logging.h"
michael@0: #include "base/memory/scoped_ptr.h"
michael@0: #include "base/win/windows_version.h"
michael@0: #include "sandbox/win/src/interceptors.h"
michael@0: #include "sandbox/win/src/internal_types.h"
michael@0: #include "sandbox/win/src/nt_internals.h"
michael@0: #include "sandbox/win/src/process_thread_interception.h"
michael@0: #include "sandbox/win/src/win_utils.h"
michael@0: 
michael@0: namespace {
michael@0: 
michael@0: template<typename T> T RoundUpToWordSize(T v) {
michael@0:   if (size_t mod = v % sizeof(size_t))
michael@0:     v += sizeof(size_t) - mod;
michael@0:   return v;
michael@0: }
michael@0: 
michael@0: template<typename T> T* RoundUpToWordSize(T* v) {
michael@0:   return reinterpret_cast<T*>(RoundUpToWordSize(reinterpret_cast<size_t>(v)));
michael@0: }
michael@0: 
michael@0: }  // namespace
michael@0: 
michael@0: namespace sandbox {
michael@0: 
michael@0: // Memory buffer mapped from the parent, with the list of handles.
michael@0: SANDBOX_INTERCEPT HandleCloserInfo* g_handles_to_close;
michael@0: 
michael@0: HandleCloser::HandleCloser() {}
michael@0: 
michael@0: ResultCode HandleCloser::AddHandle(const char16* handle_type,
michael@0:                                    const char16* handle_name) {
michael@0:   if (!handle_type)
michael@0:     return SBOX_ERROR_BAD_PARAMS;
michael@0: 
michael@0:   HandleMap::iterator names = handles_to_close_.find(handle_type);
michael@0:   if (names == handles_to_close_.end()) {  // We have no entries for this type.
michael@0:     std::pair<HandleMap::iterator, bool> result = handles_to_close_.insert(
michael@0:         HandleMap::value_type(handle_type, HandleMap::mapped_type()));
michael@0:     names = result.first;
michael@0:     if (handle_name)
michael@0:       names->second.insert(handle_name);
michael@0:   } else if (!handle_name) {  // Now we need to close all handles of this type.
michael@0:     names->second.clear();
michael@0:   } else if (!names->second.empty()) {  // Add another name for this type.
michael@0:     names->second.insert(handle_name);
michael@0:   }  // If we're already closing all handles of type then we're done.
michael@0: 
michael@0:   return SBOX_ALL_OK;
michael@0: }
michael@0: 
michael@0: size_t HandleCloser::GetBufferSize() {
michael@0:   size_t bytes_total = offsetof(HandleCloserInfo, handle_entries);
michael@0: 
michael@0:   for (HandleMap::iterator i = handles_to_close_.begin();
michael@0:        i != handles_to_close_.end(); ++i) {
michael@0:     size_t bytes_entry = offsetof(HandleListEntry, handle_type) +
michael@0:         (i->first.size() + 1) * sizeof(char16);
michael@0:     for (HandleMap::mapped_type::iterator j = i->second.begin();
michael@0:          j != i->second.end(); ++j) {
michael@0:       bytes_entry += ((*j).size() + 1) * sizeof(char16);
michael@0:     }
michael@0: 
michael@0:     // Round up to the nearest multiple of word size.
michael@0:     bytes_entry = RoundUpToWordSize(bytes_entry);
michael@0:     bytes_total += bytes_entry;
michael@0:   }
michael@0: 
michael@0:   return bytes_total;
michael@0: }
michael@0: 
michael@0: bool HandleCloser::InitializeTargetHandles(TargetProcess* target) {
michael@0:   // Do nothing on an empty list (global pointer already initialized to NULL).
michael@0:   if (handles_to_close_.empty())
michael@0:     return true;
michael@0: 
michael@0:   size_t bytes_needed = GetBufferSize();
michael@0:   scoped_ptr<size_t[]> local_buffer(
michael@0:       new size_t[bytes_needed / sizeof(size_t)]);
michael@0: 
michael@0:   if (!SetupHandleList(local_buffer.get(), bytes_needed))
michael@0:     return false;
michael@0: 
michael@0:   HANDLE child = target->Process();
michael@0: 
michael@0:   // Allocate memory in the target process without specifying the address
michael@0:   void* remote_data = ::VirtualAllocEx(child, NULL, bytes_needed,
michael@0:                                        MEM_COMMIT, PAGE_READWRITE);
michael@0:   if (NULL == remote_data)
michael@0:     return false;
michael@0: 
michael@0:   // Copy the handle buffer over.
michael@0:   SIZE_T bytes_written;
michael@0:   BOOL result = ::WriteProcessMemory(child, remote_data, local_buffer.get(),
michael@0:                                      bytes_needed, &bytes_written);
michael@0:   if (!result || bytes_written != bytes_needed) {
michael@0:     ::VirtualFreeEx(child, remote_data, 0, MEM_RELEASE);
michael@0:     return false;
michael@0:   }
michael@0: 
michael@0:   g_handles_to_close = reinterpret_cast<HandleCloserInfo*>(remote_data);
michael@0: 
michael@0:   ResultCode rc = target->TransferVariable("g_handles_to_close",
michael@0:                                            &g_handles_to_close,
michael@0:                                            sizeof(g_handles_to_close));
michael@0: 
michael@0:   return (SBOX_ALL_OK == rc);
michael@0: }
michael@0: 
michael@0: bool HandleCloser::SetupHandleList(void* buffer, size_t buffer_bytes) {
michael@0:   ::ZeroMemory(buffer, buffer_bytes);
michael@0:   HandleCloserInfo* handle_info = reinterpret_cast<HandleCloserInfo*>(buffer);
michael@0:   handle_info->record_bytes = buffer_bytes;
michael@0:   handle_info->num_handle_types = handles_to_close_.size();
michael@0: 
michael@0:   char16* output = reinterpret_cast<char16*>(&handle_info->handle_entries[0]);
michael@0:   char16* end = reinterpret_cast<char16*>(
michael@0:       reinterpret_cast<char*>(buffer) + buffer_bytes);
michael@0:   for (HandleMap::iterator i = handles_to_close_.begin();
michael@0:        i != handles_to_close_.end(); ++i) {
michael@0:     if (output >= end)
michael@0:       return false;
michael@0:     HandleListEntry* list_entry = reinterpret_cast<HandleListEntry*>(output);
michael@0:     output = &list_entry->handle_type[0];
michael@0: 
michael@0:     // Copy the typename and set the offset and count.
michael@0:     i->first._Copy_s(output, i->first.size(), i->first.size());
michael@0:     *(output += i->first.size()) = L'\0';
michael@0:     output++;
michael@0:     list_entry->offset_to_names = reinterpret_cast<char*>(output) -
michael@0:         reinterpret_cast<char*>(list_entry);
michael@0:     list_entry->name_count = i->second.size();
michael@0: 
michael@0:     // Copy the handle names.
michael@0:     for (HandleMap::mapped_type::iterator j = i->second.begin();
michael@0:          j != i->second.end(); ++j) {
michael@0:       output = std::copy((*j).begin(), (*j).end(), output) + 1;
michael@0:     }
michael@0: 
michael@0:     // Round up to the nearest multiple of sizeof(size_t).
michael@0:     output = RoundUpToWordSize(output);
michael@0:     list_entry->record_bytes = reinterpret_cast<char*>(output) -
michael@0:         reinterpret_cast<char*>(list_entry);
michael@0:   }
michael@0: 
michael@0:   DCHECK_EQ(reinterpret_cast<size_t>(output), reinterpret_cast<size_t>(end));
michael@0:   return output <= end;
michael@0: }
michael@0: 
michael@0: bool HandleCloser::SetupHandleInterceptions(InterceptionManager* manager) {
michael@0:   // We need to intercept CreateThread if we're closing ALPC port clients.
michael@0:   HandleMap::iterator names = handles_to_close_.find(L"ALPC Port");
michael@0:   if (base::win::GetVersion() >= base::win::VERSION_VISTA &&
michael@0:       names != handles_to_close_.end() &&
michael@0:       (names->second.empty() || names->second.size() == 0)) {
michael@0:     if (!INTERCEPT_EAT(manager, kKerneldllName, CreateThread,
michael@0:                        CREATE_THREAD_ID, 28)) {
michael@0:       return false;
michael@0:     }
michael@0:     if (!INTERCEPT_EAT(manager, kKerneldllName, GetUserDefaultLCID,
michael@0:                        GET_USER_DEFAULT_LCID_ID, 4)) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0:   }
michael@0: 
michael@0:   return true;
michael@0: }
michael@0: 
michael@0: bool GetHandleName(HANDLE handle, string16* handle_name) {
michael@0:   static NtQueryObject QueryObject = NULL;
michael@0:   if (!QueryObject)
michael@0:     ResolveNTFunctionPtr("NtQueryObject", &QueryObject);
michael@0: 
michael@0:   ULONG size = MAX_PATH;
michael@0:   scoped_ptr<UNICODE_STRING, base::FreeDeleter> name;
michael@0:   NTSTATUS result;
michael@0: 
michael@0:   do {
michael@0:     name.reset(static_cast<UNICODE_STRING*>(malloc(size)));
michael@0:     DCHECK(name.get());
michael@0:     result = QueryObject(handle, ObjectNameInformation, name.get(),
michael@0:                          size, &size);
michael@0:   } while (result == STATUS_INFO_LENGTH_MISMATCH ||
michael@0:            result == STATUS_BUFFER_OVERFLOW);
michael@0: 
michael@0:   if (NT_SUCCESS(result) && name->Buffer && name->Length)
michael@0:     handle_name->assign(name->Buffer, name->Length / sizeof(wchar_t));
michael@0:   else
michael@0:     handle_name->clear();
michael@0: 
michael@0:   return NT_SUCCESS(result);
michael@0: }
michael@0: 
michael@0: }  // namespace sandbox