1// Copyright (c) 2006-2010 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#ifndef SANDBOX_SRC_WIN_UTILS_H_
6#define SANDBOX_SRC_WIN_UTILS_H_
7
8#include <windows.h>
9#include <string>
10
11#include "base/basictypes.h"
12#include "base/strings/string16.h"
13
14namespace sandbox {
15
16// Prefix for path used by NT calls.
17const wchar_t kNTPrefix[] = L"\\??\\";
18const size_t kNTPrefixLen = arraysize(kNTPrefix) - 1;
19
20const wchar_t kNTObjManPrefix[] = L"\\Device\\";
21const size_t kNTObjManPrefixLen = arraysize(kNTObjManPrefix) - 1;
22
23// Automatically acquires and releases a lock when the object is
24// is destroyed.
25class AutoLock {
26 public:
27  // Acquires the lock.
28  explicit AutoLock(CRITICAL_SECTION *lock) : lock_(lock) {
29    ::EnterCriticalSection(lock);
30  };
31
32  // Releases the lock;
33  ~AutoLock() {
34    ::LeaveCriticalSection(lock_);
35  };
36
37 private:
38  CRITICAL_SECTION *lock_;
39  DISALLOW_IMPLICIT_CONSTRUCTORS(AutoLock);
40};
41
42// Basic implementation of a singleton which calls the destructor
43// when the exe is shutting down or the DLL is being unloaded.
44template <typename Derived>
45class SingletonBase {
46 public:
47  static Derived* GetInstance() {
48    static Derived* instance = NULL;
49    if (NULL == instance) {
50      instance = new Derived();
51      // Microsoft CRT extension. In an exe this this called after
52      // winmain returns, in a dll is called in DLL_PROCESS_DETACH
53      _onexit(OnExit);
54    }
55    return instance;
56  }
57
58 private:
59  // this is the function that gets called by the CRT when the
60  // process is shutting down.
61  static int __cdecl OnExit() {
62    delete GetInstance();
63    return 0;
64  }
65};
66
67// Convert a short path (C:\path~1 or \\??\\c:\path~1) to the long version of
68// the path. If the path is not a valid filesystem path, the function returns
69// false and the output parameter is not modified.
70bool ConvertToLongPath(const base::string16& short_path,
71                       base::string16* long_path);
72
73// Sets result to true if the path contains a reparse point. The return value
74// is ERROR_SUCCESS when the function succeeds or the appropriate error code
75// when the function fails.
76// This function is not smart. It looks for each element in the path and
77// returns true if any of them is a reparse point.
78DWORD IsReparsePoint(const base::string16& full_path, bool* result);
79
80// Returns true if the handle corresponds to the object pointed by this path.
81bool SameObject(HANDLE handle, const wchar_t* full_path);
82
83// Resolves a handle to an nt path. Returns true if the handle can be resolved.
84bool GetPathFromHandle(HANDLE handle, base::string16* path);
85
86// Resolves a win32 path to an nt path using GetPathFromHandle. The path must
87// exist. Returs true if the translation was succesful.
88bool GetNtPathFromWin32Path(const base::string16& path,
89                            base::string16* nt_path);
90
91// Translates a reserved key name to its handle.
92// For example "HKEY_LOCAL_MACHINE" returns HKEY_LOCAL_MACHINE.
93// Returns NULL if the name does not represent any reserved key name.
94HKEY GetReservedKeyFromName(const base::string16& name);
95
96// Resolves a user-readable registry path to a system-readable registry path.
97// For example, HKEY_LOCAL_MACHINE\\Software\\microsoft is translated to
98// \\registry\\machine\\software\\microsoft. Returns false if the path
99// cannot be resolved.
100bool ResolveRegistryName(base::string16 name, base::string16* resolved_name);
101
102// Writes |length| bytes from the provided |buffer| into the address space of
103// |child_process|, at the specified |address|, preserving the original write
104// protection attributes. Returns true on success.
105bool WriteProtectedChildMemory(HANDLE child_process, void* address,
106                               const void* buffer, size_t length);
107
108}  // namespace sandbox
109
110// Resolves a function name in NTDLL to a function pointer. The second parameter
111// is a pointer to the function pointer.
112void ResolveNTFunctionPtr(const char* name, void* ptr);
113
114#endif  // SANDBOX_SRC_WIN_UTILS_H_
115