license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 1 | // Copyright (c) 2006-2008 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. |
initial.commit | 3f4a732 | 2008-07-27 06:49:38 +0900 | [diff] [blame] | 4 | |
| 5 | // This file declares a helpers to intercept functions from a DLL. |
| 6 | // |
| 7 | // This set of functions are designed to intercept functions for a |
| 8 | // specific DLL imported from another DLL. This is the case when, |
| 9 | // for example, we want to intercept CertDuplicateCertificateContext |
| 10 | // function (exported from crypt32.dll) called by wininet.dll. |
| 11 | |
| 12 | #ifndef BASE_IAT_PATCH_H__ |
| 13 | #define BASE_IAT_PATCH_H__ |
| 14 | |
| 15 | #include <windows.h> |
| 16 | #include "base/basictypes.h" |
| 17 | #include "base/pe_image.h" |
| 18 | |
| 19 | namespace iat_patch { |
| 20 | |
| 21 | // Helper to intercept a function in an import table of a specific |
| 22 | // module. |
| 23 | // |
| 24 | // Arguments: |
| 25 | // module_handle Module to be intercepted |
| 26 | // imported_from_module Module that exports the symbol |
| 27 | // function_name Name of the API to be intercepted |
| 28 | // new_function Interceptor function |
| 29 | // old_function Receives the original function pointer |
| 30 | // iat_thunk Receives pointer to IAT_THUNK_DATA |
| 31 | // for the API from the import table. |
| 32 | // |
| 33 | // Returns: Returns NO_ERROR on success or Windows error code |
| 34 | // as defined in winerror.h |
| 35 | // |
| 36 | DWORD InterceptImportedFunction(HMODULE module_handle, |
| 37 | const char* imported_from_module, |
| 38 | const char* function_name, |
| 39 | void* new_function, |
| 40 | void** old_function, |
| 41 | IMAGE_THUNK_DATA** iat_thunk); |
| 42 | |
| 43 | // Restore intercepted IAT entry with the original function. |
| 44 | // |
| 45 | // Arguments: |
| 46 | // intercept_function Interceptor function |
| 47 | // original_function Receives the original function pointer |
| 48 | // |
| 49 | // Returns: Returns NO_ERROR on success or Windows error code |
| 50 | // as defined in winerror.h |
| 51 | // |
| 52 | DWORD RestoreImportedFunction(void* intercept_function, |
| 53 | void* original_function, |
| 54 | IMAGE_THUNK_DATA* iat_thunk); |
| 55 | |
| 56 | // Change the page protection (of code pages) to writable and copy |
| 57 | // the data at the specified location |
| 58 | // |
| 59 | // Arguments: |
| 60 | // old_code Target location to copy |
| 61 | // new_code Source |
| 62 | // length Number of bytes to copy |
| 63 | // |
| 64 | // Returns: Windows error code (winerror.h). NO_ERROR if successful |
| 65 | // |
| 66 | DWORD ModifyCode(void* old_code, |
| 67 | void* new_code, |
| 68 | int length); |
| 69 | |
| 70 | // A class that encapsulates IAT patching helpers and restores |
| 71 | // the original function in the destructor. |
| 72 | class IATPatchFunction { |
| 73 | public: |
| 74 | IATPatchFunction(); |
| 75 | ~IATPatchFunction(); |
| 76 | |
| 77 | // Intercept a function in an import table of a specific |
| 78 | // module. Save the original function and the import |
| 79 | // table address. These values will be used later |
| 80 | // during Unpatch |
| 81 | // |
| 82 | // Arguments: |
| 83 | // module_handle Module to be intercepted |
| 84 | // imported_from_module Module that exports the 'function_name' |
| 85 | // function_name Name of the API to be intercepted |
| 86 | // |
| 87 | // Returns: Windows error code (winerror.h). NO_ERROR if successful |
| 88 | // |
| 89 | DWORD Patch(HMODULE module_handle, |
| 90 | const char* imported_from_module, |
| 91 | const char* function_name, |
| 92 | void* new_function); |
| 93 | |
| 94 | // Unpatch the IAT entry using internally saved original |
| 95 | // function. |
| 96 | // |
| 97 | // Returns: Windows error code (winerror.h). NO_ERROR if successful |
| 98 | // |
| 99 | DWORD Unpatch(); |
| 100 | |
| 101 | bool is_patched() const { |
| 102 | return (NULL != intercept_function_); |
| 103 | } |
| 104 | |
| 105 | private: |
| 106 | void* intercept_function_; |
| 107 | void* original_function_; |
| 108 | IMAGE_THUNK_DATA* iat_thunk_; |
| 109 | |
| 110 | DISALLOW_EVIL_CONSTRUCTORS(IATPatchFunction); |
| 111 | }; |
| 112 | |
| 113 | } // namespace iat_patch |
| 114 | |
| 115 | #endif // BASE_IAT_PATCH_H__ |
license.bot | f003cfe | 2008-08-24 09:55:55 +0900 | [diff] [blame^] | 116 | |