// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Defines InterceptionAgent, the class in charge of setting up interceptions
// from the inside of the sandboxed process. For more details see
// http://dev.chromium.org/developers/design-documents/sandbox .
#ifndef SANDBOX_SRC_INTERCEPTION_AGENT_H__
#define SANDBOX_SRC_INTERCEPTION_AGENT_H__
#include "base/basictypes.h"
#include "sandbox/win/src/nt_internals.h"
#include "sandbox/win/src/sandbox_types.h"
namespace sandbox {
// Internal structures used for communication between the broker and the target.
struct DllInterceptionData;
struct SharedMemory;
struct DllPatchInfo;
class ResolverThunk;
// The InterceptionAgent executes on the target application, and it is in charge
// of setting up the desired interceptions or indicating what module needs to
// be unloaded.
//
// The exposed API consists of three methods: GetInterceptionAgent to retrieve
// the single class instance, OnDllLoad and OnDllUnload to process a dll being
// loaded and unloaded respectively.
//
// This class assumes that it will get called for every dll being loaded,
// starting with kernel32, so the singleton will be instantiated from within the
// loader lock.
class InterceptionAgent {
public:
// Returns the single InterceptionAgent object for this process.
static InterceptionAgent* GetInterceptionAgent();
// This method should be invoked whenever a new dll is loaded to perform the
// required patches. If the return value is false, this dll should not be
// allowed to load.
//
// full_path is the (optional) full name of the module being loaded and name
// is the internal module name. If full_path is provided, it will be used
// before the internal name to determine if we care about this dll.
bool OnDllLoad(const UNICODE_STRING* full_path, const UNICODE_STRING* name,
void* base_address);
// Performs cleanup when a dll is unloaded.
void OnDllUnload(void* base_address);
private:
~InterceptionAgent() {}
// Performs initialization of the singleton.
bool Init(SharedMemory* shared_memory);
// Returns true if we are interested on this dll. dll_info is an entry of the
// list of intercepted dlls.
bool DllMatch(const UNICODE_STRING* full_path, const UNICODE_STRING* name,
const DllPatchInfo* dll_info);
// Performs the patching of the dll loaded at base_address.
// The patches to perform are described on dll_info, and thunks is the thunk
// storage for the whole dll.
// Returns true on success.
bool PatchDll(const DllPatchInfo* dll_info, DllInterceptionData* thunks);
// Returns a resolver for a given interception type.
ResolverThunk* GetResolver(InterceptionType type);
// Shared memory containing the list of functions to intercept.
SharedMemory* interceptions_;
// Array of thunk data buffers for the intercepted dlls. This object singleton
// is allocated with a placement new with enough space to hold the complete
// array of pointers, not just the first element.
DllInterceptionData* dlls_[1];
DISALLOW_IMPLICIT_CONSTRUCTORS(InterceptionAgent);
};
} // namespace sandbox
#endif // SANDBOX_SRC_INTERCEPTION_AGENT_H__