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 16 namespace sandbox { 17 18 // Internal structures used for communication between the broker and the target. 19 struct DllInterceptionData; 20 struct SharedMemory; 21 struct DllPatchInfo; 22 23 class 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. 36 class 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: ~InterceptionAgent()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