1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
|
// Copyright (c) 2012 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.
#include "content/renderer/renderer_main_platform_delegate.h"
#include <signal.h>
#include "base/command_line.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "base/win/win_util.h"
#include "content/common/injection_test_dll.h"
#include "content/public/common/content_switches.h"
#include "content/public/renderer/render_thread.h"
#include "sandbox/src/sandbox.h"
#include "skia/ext/skia_sandbox_support_win.h"
#include "unicode/timezone.h"
namespace {
// In order to have Theme support, we need to connect to the theme service.
// This needs to be done before we lock down the renderer. Officially this
// can be done with OpenThemeData() but it fails unless you pass a valid
// window at least the first time. Interestingly, the very act of creating a
// window also sets the connection to the theme service.
void EnableThemeSupportForRenderer(bool no_sandbox) {
HWINSTA current = NULL;
HWINSTA winsta0 = NULL;
if (!no_sandbox) {
current = ::GetProcessWindowStation();
winsta0 = ::OpenWindowStationW(L"WinSta0", FALSE, GENERIC_READ);
if (!winsta0 || !::SetProcessWindowStation(winsta0)) {
// Could not set the alternate window station. There is a possibility
// that the theme wont be correctly initialized on XP.
NOTREACHED() << "Unable to switch to WinSt0";
}
}
HWND window = ::CreateWindowExW(0, L"Static", L"", WS_POPUP | WS_DISABLED,
CW_USEDEFAULT, 0, 0, 0, HWND_MESSAGE, NULL,
::GetModuleHandleA(NULL), NULL);
if (!window) {
DLOG(WARNING) << "failed to enable theme support";
} else {
::DestroyWindow(window);
}
if (!no_sandbox) {
// Revert the window station.
if (!current || !::SetProcessWindowStation(current)) {
// We failed to switch back to the secure window station. This might
// confuse the renderer enough that we should kill it now.
LOG(FATAL) << "Failed to restore alternate window station";
}
if (!::CloseWindowStation(winsta0)) {
// We might be leaking a winsta0 handle. This is a security risk, but
// since we allow fail over to no desktop protection in low memory
// condition, this is not a big risk.
NOTREACHED();
}
}
}
// Windows-only skia sandbox support
void SkiaPreCacheFont(LOGFONT logfont) {
content::RenderThread* render_thread = content::RenderThread::Get();
if (render_thread) {
render_thread->PreCacheFont(logfont);
}
}
void __cdecl ForceCrashOnSigAbort(int) {
*((int*)0) = 0x1337;
}
void InitExitInterceptions() {
// If code subsequently tries to exit using exit(), _exit(), abort(), or
// ExitProcess(), force a crash (since otherwise these would be silent
// terminations and fly under the radar).
base::win::SetShouldCrashOnProcessDetach(true);
// Prevent CRT's abort code from prompting a dialog or trying to "report" it.
// Disabling the _CALL_REPORTFAULT behavior is important since otherwise it
// has the sideffect of clearing our exception filter, which means we
// don't get any crash.
_set_abort_behavior(0, _WRITE_ABORT_MSG | _CALL_REPORTFAULT);
// Set a SIGABRT handler for good measure. We will crash even if the default
// is left in place, however this allows us to crash earlier. And it also
// lets us crash in response to code which might directly call raise(SIGABRT)
signal(SIGABRT, ForceCrashOnSigAbort);
}
} // namespace
RendererMainPlatformDelegate::RendererMainPlatformDelegate(
const content::MainFunctionParams& parameters)
: parameters_(parameters),
sandbox_test_module_(NULL) {
}
RendererMainPlatformDelegate::~RendererMainPlatformDelegate() {
}
void RendererMainPlatformDelegate::PlatformInitialize() {
InitExitInterceptions();
// Be mindful of what resources you acquire here. They can be used by
// malicious code if the renderer gets compromised.
const CommandLine& command_line = parameters_.command_line;
bool no_sandbox = command_line.HasSwitch(switches::kNoSandbox);
EnableThemeSupportForRenderer(no_sandbox);
if (!no_sandbox) {
// ICU DateFormat class (used in base/time_format.cc) needs to get the
// Olson timezone ID by accessing the registry keys under
// HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones.
// After TimeZone::createDefault is called once here, the timezone ID is
// cached and there's no more need to access the registry. If the sandbox
// is disabled, we don't have to make this dummy call.
scoped_ptr<icu::TimeZone> zone(icu::TimeZone::createDefault());
SetSkiaEnsureTypefaceAccessible(SkiaPreCacheFont);
}
}
void RendererMainPlatformDelegate::PlatformUninitialize() {
// At this point we are shutting down in a normal code path, so undo our
// hack to crash on exit.
base::win::SetShouldCrashOnProcessDetach(false);
}
bool RendererMainPlatformDelegate::InitSandboxTests(bool no_sandbox) {
const CommandLine& command_line = parameters_.command_line;
DVLOG(1) << "Started renderer with " << command_line.GetCommandLineString();
sandbox::TargetServices* target_services =
parameters_.sandbox_info->target_services;
if (target_services && !no_sandbox) {
std::wstring test_dll_name =
command_line.GetSwitchValueNative(switches::kTestSandbox);
if (!test_dll_name.empty()) {
sandbox_test_module_ = LoadLibrary(test_dll_name.c_str());
DCHECK(sandbox_test_module_);
if (!sandbox_test_module_) {
return false;
}
}
}
return true;
}
bool RendererMainPlatformDelegate::EnableSandbox() {
sandbox::TargetServices* target_services =
parameters_.sandbox_info->target_services;
if (target_services) {
// Cause advapi32 to load before the sandbox is turned on.
unsigned int dummy_rand;
rand_s(&dummy_rand);
// Warm up language subsystems before the sandbox is turned on.
::GetUserDefaultLangID();
::GetUserDefaultLCID();
target_services->LowerToken();
return true;
}
return false;
}
void RendererMainPlatformDelegate::RunSandboxTests() {
if (sandbox_test_module_) {
RunRendererTests run_security_tests =
reinterpret_cast<RunRendererTests>(GetProcAddress(sandbox_test_module_,
kRenderTestCall));
DCHECK(run_security_tests);
if (run_security_tests) {
int test_count = 0;
DVLOG(1) << "Running renderer security tests";
BOOL result = run_security_tests(&test_count);
CHECK(result) << "Test number " << test_count << " has failed.";
}
}
}
|
