• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright 2018 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #ifdef UNSAFE_BUFFERS_BUILD
6 // TODO(crbug.com/40284755): Remove this and spanify to fix the errors.
7 #pragma allow_unsafe_buffers
8 #endif
9 
10 #ifndef BASE_WIN_SCOPED_HANDLE_VERIFIER_H_
11 #define BASE_WIN_SCOPED_HANDLE_VERIFIER_H_
12 
13 #include <memory>
14 #include <unordered_map>
15 
16 #include "base/base_export.h"
17 #include "base/debug/stack_trace.h"
18 #include "base/hash/hash.h"
19 #include "base/memory/raw_ptr.h"
20 #include "base/synchronization/lock_impl.h"
21 #include "base/win/windows_types.h"
22 
23 namespace base {
24 namespace win {
25 enum class HandleOperation;
26 namespace internal {
27 
28 struct HandleHash {
operatorHandleHash29   size_t operator()(const HANDLE& handle) const {
30     return base::FastHash(byte_span_from_ref(handle));
31   }
32 };
33 
34 struct ScopedHandleVerifierInfo {
35   ScopedHandleVerifierInfo(const void* owner,
36                            const void* pc1,
37                            const void* pc2,
38                            std::unique_ptr<debug::StackTrace> stack,
39                            DWORD thread_id);
40   ~ScopedHandleVerifierInfo();
41 
42   ScopedHandleVerifierInfo(const ScopedHandleVerifierInfo&) = delete;
43   ScopedHandleVerifierInfo& operator=(const ScopedHandleVerifierInfo&) = delete;
44   ScopedHandleVerifierInfo(ScopedHandleVerifierInfo&&) noexcept;
45   ScopedHandleVerifierInfo& operator=(ScopedHandleVerifierInfo&&) noexcept;
46 
47   raw_ptr<const void> owner;
48   raw_ptr<const void> pc1;
49   raw_ptr<const void> pc2;
50   std::unique_ptr<debug::StackTrace> stack;
51   DWORD thread_id;
52 };
53 
54 // Implements the actual object that is verifying handles for this process.
55 // The active instance is shared across the module boundary but there is no
56 // way to delete this object from the wrong side of it (or any side, actually).
57 // We need [[clang::lto_visibility_public]] because instances of this class are
58 // passed across module boundaries. This means different modules must have
59 // compatible definitions of the class even when whole program optimization is
60 // enabled - which is what this attribute accomplishes. The pragma stops MSVC
61 // from emitting an unrecognized attribute warning.
62 #pragma warning(push)
63 #pragma warning(disable : 5030)
64 class [[clang::lto_visibility_public, nodiscard]] ScopedHandleVerifier {
65 #pragma warning(pop)
66  public:
67   ScopedHandleVerifier(const ScopedHandleVerifier&) = delete;
68   ScopedHandleVerifier& operator=(const ScopedHandleVerifier&) = delete;
69 
70   // Retrieves the current verifier.
71   static ScopedHandleVerifier* Get();
72 
73   // The methods required by HandleTraits. They are virtual because we need to
74   // forward the call execution to another module, instead of letting the
75   // compiler call the version that is linked in the current module.
76   virtual bool CloseHandle(HANDLE handle);
77   virtual void StartTracking(HANDLE handle, const void* owner, const void* pc1,
78                              const void* pc2);
79   virtual void StopTracking(HANDLE handle, const void* owner, const void* pc1,
80                             const void* pc2);
81   virtual void Disable();
82   virtual void OnHandleBeingClosed(HANDLE handle, HandleOperation operation);
83   virtual HMODULE GetModule() const;
84 
85  private:
86   explicit ScopedHandleVerifier(bool enabled);
87   ~ScopedHandleVerifier();  // Not implemented.
88 
89   void StartTrackingImpl(HANDLE handle, const void* owner, const void* pc1,
90                          const void* pc2);
91   void StopTrackingImpl(HANDLE handle, const void* owner, const void* pc1,
92                         const void* pc2);
93   void OnHandleBeingClosedImpl(HANDLE handle, HandleOperation operation);
94 
95   static base::internal::LockImpl* GetLock();
96   static void InstallVerifier();
97   static void ThreadSafeAssignOrCreateScopedHandleVerifier(
98       ScopedHandleVerifier * existing_verifier, bool enabled);
99 
100   base::debug::StackTrace creation_stack_;
101   bool enabled_;
102   raw_ptr<base::internal::LockImpl> lock_;
103   std::unordered_map<HANDLE, ScopedHandleVerifierInfo, HandleHash> map_;
104 };
105 
106 // This testing function returns the module that the HandleVerifier concrete
107 // implementation was instantiated in.
108 BASE_EXPORT HMODULE GetHandleVerifierModuleForTesting();
109 
110 }  // namespace internal
111 }  // namespace win
112 }  // namespace base
113 
114 #endif  // BASE_WIN_SCOPED_HANDLE_VERIFIER_H_
115