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
|
/* -*- 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/. */
/* JSPrincipals and related interfaces. */
#ifndef js_Principals_h
#define js_Principals_h
#include "mozilla/Atomics.h"
#include <stdint.h>
#include "jspubtd.h"
struct JSStructuredCloneReader;
struct JSStructuredCloneWriter;
struct JSPrincipals {
/* Don't call "destroy"; use reference counting macros below. */
mozilla::Atomic<int32_t, mozilla::SequentiallyConsistent> refcount{0};
#ifdef JS_DEBUG
/* A helper to facilitate principals debugging. */
uint32_t debugToken;
#endif
JSPrincipals() = default;
void setDebugToken(uint32_t token) {
#ifdef JS_DEBUG
debugToken = token;
#endif
}
/*
* Write the principals with the given |writer|. Return false on failure,
* true on success.
*/
virtual bool write(JSContext* cx, JSStructuredCloneWriter* writer) = 0;
/*
* Whether the principal corresponds to a System or AddOn Principal.
* Technically this also checks for an ExpandedAddonPrincipal.
*/
virtual bool isSystemOrAddonPrincipal() = 0;
/*
* This is not defined by the JS engine but should be provided by the
* embedding.
*/
JS_PUBLIC_API void dump();
};
extern JS_PUBLIC_API void JS_HoldPrincipals(JSPrincipals* principals);
extern JS_PUBLIC_API void JS_DropPrincipals(JSContext* cx,
JSPrincipals* principals);
// Return whether the first principal subsumes the second. The exact meaning of
// 'subsumes' is left up to the browser. Subsumption is checked inside the JS
// engine when determining, e.g., which stack frames to display in a backtrace.
typedef bool (*JSSubsumesOp)(JSPrincipals* first, JSPrincipals* second);
/*
* Used to check if a CSP instance wants to disable eval() and friends.
* See GlobalObject::isRuntimeCodeGenEnabled() in vm/GlobalObject.cpp.
*/
typedef bool (*JSCSPEvalChecker)(JSContext* cx, JS::HandleString code);
struct JSSecurityCallbacks {
JSCSPEvalChecker contentSecurityPolicyAllows;
JSSubsumesOp subsumes;
};
extern JS_PUBLIC_API void JS_SetSecurityCallbacks(
JSContext* cx, const JSSecurityCallbacks* callbacks);
extern JS_PUBLIC_API const JSSecurityCallbacks* JS_GetSecurityCallbacks(
JSContext* cx);
/*
* Code running with "trusted" principals will be given a deeper stack
* allocation than ordinary scripts. This allows trusted script to run after
* untrusted script has exhausted the stack. This function sets the
* runtime-wide trusted principal.
*
* This principals is not held (via JS_HoldPrincipals/JS_DropPrincipals).
* Instead, the caller must ensure that the given principals stays valid for as
* long as 'cx' may point to it. If the principals would be destroyed before
* 'cx', JS_SetTrustedPrincipals must be called again, passing nullptr for
* 'prin'.
*/
extern JS_PUBLIC_API void JS_SetTrustedPrincipals(JSContext* cx,
JSPrincipals* prin);
typedef void (*JSDestroyPrincipalsOp)(JSPrincipals* principals);
/*
* Initialize the callback that is called to destroy JSPrincipals instance
* when its reference counter drops to zero. The initialization can be done
* only once per JS runtime.
*/
extern JS_PUBLIC_API void JS_InitDestroyPrincipalsCallback(
JSContext* cx, JSDestroyPrincipalsOp destroyPrincipals);
/*
* Read a JSPrincipals instance from the given |reader| and initialize the out
* paratemer |outPrincipals| to the JSPrincipals instance read.
*
* Return false on failure, true on success. The |outPrincipals| parameter
* should not be modified if false is returned.
*
* The caller is not responsible for calling JS_HoldPrincipals on the resulting
* JSPrincipals instance, the JSReadPrincipalsOp must increment the refcount of
* the resulting JSPrincipals on behalf of the caller.
*/
using JSReadPrincipalsOp = bool (*)(JSContext* cx,
JSStructuredCloneReader* reader,
JSPrincipals** outPrincipals);
/*
* Initialize the callback that is called to read JSPrincipals instances from a
* buffer. The initialization can be done only once per JS runtime.
*/
extern JS_PUBLIC_API void JS_InitReadPrincipalsCallback(
JSContext* cx, JSReadPrincipalsOp read);
namespace JS {
class MOZ_RAII AutoHoldPrincipals {
JSContext* cx_;
JSPrincipals* principals_ = nullptr;
public:
explicit AutoHoldPrincipals(JSContext* cx, JSPrincipals* principals = nullptr)
: cx_(cx) {
reset(principals);
}
~AutoHoldPrincipals() { reset(nullptr); }
void reset(JSPrincipals* principals) {
if (principals) {
JS_HoldPrincipals(principals);
}
if (principals_) {
JS_DropPrincipals(cx_, principals_);
}
principals_ = principals;
}
JSPrincipals* get() const { return principals_; }
};
} // namespace JS
#endif /* js_Principals_h */
|