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
|
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/WindowsProcessMitigations.h"
#include <processthreadsapi.h>
#include "mozilla/DynamicallyLinkedFunctionPtr.h"
#include "mozilla/WindowsVersion.h"
static_assert(sizeof(PROCESS_MITIGATION_DYNAMIC_CODE_POLICY) == 4);
namespace mozilla {
static decltype(&::GetProcessMitigationPolicy)
FetchGetProcessMitigationPolicyFunc() {
static const StaticDynamicallyLinkedFunctionPtr<
decltype(&::GetProcessMitigationPolicy)>
pGetProcessMitigationPolicy(L"kernel32.dll",
"GetProcessMitigationPolicy");
return pGetProcessMitigationPolicy;
}
static bool sWin32kLockedDownInPolicy = false;
MFBT_API bool IsWin32kLockedDown() {
static bool sWin32kLockedDown = []() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
PROCESS_MITIGATION_SYSTEM_CALL_DISABLE_POLICY polInfo;
if (!pGetProcessMitigationPolicy ||
!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessSystemCallDisablePolicy, &polInfo,
sizeof(polInfo))) {
// We failed to get pointer to GetProcessMitigationPolicy or the call
// to it failed, so just return what the sandbox policy says.
return sWin32kLockedDownInPolicy;
}
return !!polInfo.DisallowWin32kSystemCalls;
}();
return sWin32kLockedDown;
}
MFBT_API void SetWin32kLockedDownInPolicy() {
sWin32kLockedDownInPolicy = true;
}
MFBT_API bool IsDynamicCodeDisabled() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
if (!pGetProcessMitigationPolicy) {
return false;
}
PROCESS_MITIGATION_DYNAMIC_CODE_POLICY polInfo;
if (!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessDynamicCodePolicy, &polInfo,
sizeof(polInfo))) {
return false;
}
return polInfo.ProhibitDynamicCode;
}
MFBT_API bool IsEafPlusEnabled() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
if (!pGetProcessMitigationPolicy) {
return false;
}
PROCESS_MITIGATION_PAYLOAD_RESTRICTION_POLICY polInfo;
if (!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessPayloadRestrictionPolicy, &polInfo,
sizeof(polInfo))) {
return false;
}
return polInfo.EnableExportAddressFilterPlus;
}
MFBT_API bool IsUserShadowStackEnabled() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
if (!pGetProcessMitigationPolicy) {
return false;
}
PROCESS_MITIGATION_USER_SHADOW_STACK_POLICY polInfo;
if (!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessUserShadowStackPolicy, &polInfo,
sizeof(polInfo))) {
return false;
}
return polInfo.EnableUserShadowStack;
}
MFBT_API bool IsPreferLoadFromSystem32Available() {
return mozilla::IsWin10AnniversaryUpdateOrLater();
}
MFBT_API bool IsPreferLoadFromSystem32Enabled() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
if (!pGetProcessMitigationPolicy) {
return false;
}
PROCESS_MITIGATION_IMAGE_LOAD_POLICY imgLoadPol{};
if (!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessImageLoadPolicy, &imgLoadPol,
sizeof(imgLoadPol))) {
return false;
}
return imgLoadPol.PreferSystem32Images;
}
MFBT_API bool EnablePreferLoadFromSystem32() {
auto pGetProcessMitigationPolicy = FetchGetProcessMitigationPolicyFunc();
if (!pGetProcessMitigationPolicy) {
return false;
}
static const mozilla::StaticDynamicallyLinkedFunctionPtr<
decltype(&::SetProcessMitigationPolicy)>
pSetProcessMitigationPolicy(L"kernel32.dll",
"SetProcessMitigationPolicy");
if (!pSetProcessMitigationPolicy) {
return false;
}
PROCESS_MITIGATION_IMAGE_LOAD_POLICY imgLoadPol{};
if (!pGetProcessMitigationPolicy(::GetCurrentProcess(),
ProcessImageLoadPolicy, &imgLoadPol,
sizeof(imgLoadPol))) {
return false;
}
if (imgLoadPol.PreferSystem32Images) {
return true;
}
imgLoadPol.PreferSystem32Images = 1;
return pSetProcessMitigationPolicy(ProcessImageLoadPolicy, &imgLoadPol,
sizeof(imgLoadPol));
}
} // namespace mozilla
|
