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. 4 5// Defines InterceptionAgent, the class in charge of setting up interceptions 6// from the inside of the sandboxed process. For more details see 7// http://dev.chromium.org/developers/design-documents/sandbox . 8 9#ifndef SANDBOX_SRC_INTERCEPTION_AGENT_H__ 10#define SANDBOX_SRC_INTERCEPTION_AGENT_H__ 11 12#include "base/basictypes.h" 13#include "sandbox/win/src/nt_internals.h" 14#include "sandbox/win/src/sandbox_types.h" 15 16namespace sandbox { 17 18// Internal structures used for communication between the broker and the target. 19struct DllInterceptionData; 20struct SharedMemory; 21struct DllPatchInfo; 22 23class ResolverThunk; 24 25// The InterceptionAgent executes on the target application, and it is in charge 26// of setting up the desired interceptions or indicating what module needs to 27// be unloaded. 28// 29// The exposed API consists of three methods: GetInterceptionAgent to retrieve 30// the single class instance, OnDllLoad and OnDllUnload to process a dll being 31// loaded and unloaded respectively. 32// 33// This class assumes that it will get called for every dll being loaded, 34// starting with kernel32, so the singleton will be instantiated from within the 35// loader lock. 36class InterceptionAgent { 37 public: 38 // Returns the single InterceptionAgent object for this process. 39 static InterceptionAgent* GetInterceptionAgent(); 40 41 // This method should be invoked whenever a new dll is loaded to perform the 42 // required patches. If the return value is false, this dll should not be 43 // allowed to load. 44 // 45 // full_path is the (optional) full name of the module being loaded and name 46 // is the internal module name. If full_path is provided, it will be used 47 // before the internal name to determine if we care about this dll. 48 bool OnDllLoad(const UNICODE_STRING* full_path, const UNICODE_STRING* name, 49 void* base_address); 50 51 // Performs cleanup when a dll is unloaded. 52 void OnDllUnload(void* base_address); 53 54 private: 55 ~InterceptionAgent() {} 56 57 // Performs initialization of the singleton. 58 bool Init(SharedMemory* shared_memory); 59 60 // Returns true if we are interested on this dll. dll_info is an entry of the 61 // list of intercepted dlls. 62 bool DllMatch(const UNICODE_STRING* full_path, const UNICODE_STRING* name, 63 const DllPatchInfo* dll_info); 64 65 // Performs the patching of the dll loaded at base_address. 66 // The patches to perform are described on dll_info, and thunks is the thunk 67 // storage for the whole dll. 68 // Returns true on success. 69 bool PatchDll(const DllPatchInfo* dll_info, DllInterceptionData* thunks); 70 71 // Returns a resolver for a given interception type. 72 ResolverThunk* GetResolver(InterceptionType type); 73 74 // Shared memory containing the list of functions to intercept. 75 SharedMemory* interceptions_; 76 77 // Array of thunk data buffers for the intercepted dlls. This object singleton 78 // is allocated with a placement new with enough space to hold the complete 79 // array of pointers, not just the first element. 80 DllInterceptionData* dlls_[1]; 81 82 DISALLOW_IMPLICIT_CONSTRUCTORS(InterceptionAgent); 83}; 84 85} // namespace sandbox 86 87#endif // SANDBOX_SRC_INTERCEPTION_AGENT_H__ 88