sandbox/win/src/interception_agent.h

   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:
  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__