1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 // 5 // A helper library to keep track of a user's key by SID. 6 // Used by RLZ libary. Also to be used by SearchWithGoogle library. 7 8 #include "rlz/win/lib/registry_util.h" 9 10 #include "base/process/process_handle.h" 11 #include "base/strings/utf_string_conversions.h" 12 #include "base/win/registry.h" 13 #include "base/win/windows_version.h" 14 #include "rlz/lib/assert.h" 15 #include "rlz/win/lib/process_info.h" 16 17 namespace rlz_lib { 18 19 bool RegKeyReadValue(base::win::RegKey& key, const wchar_t* name, 20 char* value, size_t* value_size) { 21 value[0] = 0; 22 23 std::wstring value_string; 24 if (key.ReadValue(name, &value_string) != ERROR_SUCCESS) { 25 return false; 26 } 27 28 if (value_string.length() > *value_size) { 29 *value_size = value_string.length(); 30 return false; 31 } 32 33 // Note that RLZ string are always ASCII by design. 34 strncpy(value, WideToUTF8(value_string).c_str(), *value_size); 35 value[*value_size - 1] = 0; 36 return true; 37 } 38 39 bool RegKeyWriteValue(base::win::RegKey& key, const wchar_t* name, 40 const char* value) { 41 std::wstring value_string(ASCIIToWide(value)); 42 return key.WriteValue(name, value_string.c_str()) == ERROR_SUCCESS; 43 } 44 45 bool HasUserKeyAccess(bool write_access) { 46 // The caller is trying to access HKEY_CURRENT_USER. Test to see if we can 47 // read from there. Don't try HKEY_CURRENT_USER because this will cause 48 // problems in the unit tests: if we open HKEY_CURRENT_USER directly here, 49 // the overriding done for unit tests will no longer work. So we try subkey 50 // "Software" which is known to always exist. 51 base::win::RegKey key; 52 if (key.Open(HKEY_CURRENT_USER, L"Software", KEY_READ) != ERROR_SUCCESS) 53 ASSERT_STRING("Could not open HKEY_CURRENT_USER"); 54 55 if (ProcessInfo::IsRunningAsSystem()) { 56 ASSERT_STRING("UserKey::HasAccess: No access as SYSTEM without SID set."); 57 return false; 58 } 59 60 if (write_access) { 61 if (base::win::GetVersion() < base::win::VERSION_VISTA) return true; 62 base::ProcessHandle process_handle = base::GetCurrentProcessHandle(); 63 base::IntegrityLevel level = base::INTEGRITY_UNKNOWN; 64 65 if (!base::GetProcessIntegrityLevel(process_handle, &level)) { 66 ASSERT_STRING("UserKey::HasAccess: Cannot determine Integrity Level."); 67 return false; 68 } 69 if (level <= base::LOW_INTEGRITY) { 70 ASSERT_STRING("UserKey::HasAccess: Cannot write from Low Integrity."); 71 return false; 72 } 73 } 74 return true; 75 } 76 77 } // namespace rlz_lib 78