1 // 2 // Copyright (C) 2014 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #ifndef TRUNKS_SCOPED_KEY_HANDLE_H_ 18 #define TRUNKS_SCOPED_KEY_HANDLE_H_ 19 20 #include "trunks/tpm_generated.h" 21 #include "trunks/trunks_export.h" 22 #include "trunks/trunks_factory.h" 23 24 namespace trunks { 25 26 // This class is used to wrap a Key or NV ram handle given by the TPM. 27 // It provides a destructor that cleans up TPM resources associated with 28 // that handle. 29 class TRUNKS_EXPORT ScopedKeyHandle { 30 public: 31 // We provide a factory to the constructor so that we can later free 32 // resources associated with the handle. 33 explicit ScopedKeyHandle(const TrunksFactory& factory); 34 ScopedKeyHandle(const TrunksFactory& factory, TPM_HANDLE handle); 35 virtual ~ScopedKeyHandle(); 36 37 // This method releases the TPM_HANDLE associated with this class. 38 // It returns the handle that was previously wrapped, and returns 39 // INVALID_HANDLE if the previous handle was unset. 40 virtual TPM_HANDLE release(); 41 42 // This method flushes all context associated with the current handle, 43 // and has the class wrap |new_handle| 44 virtual void reset(TPM_HANDLE new_handle); 45 46 // This method flushes all context associated with the current handle, 47 // and resets the internal handle of the class to the uninitialized value. 48 // Note: After reset() this class should not be used again till a new handle 49 // is injected. 50 virtual void reset(); 51 52 // This method returns a pointer to the handle associated with this class. 53 // This method does not transfer ownership. 54 virtual TPM_HANDLE* ptr(); 55 56 // This method returns the handle currectly associated with the class. 57 // This method does not transfer ownership, therefore the handle returned 58 // might be stale. 59 virtual TPM_HANDLE get() const; 60 61 private: 62 const TrunksFactory& factory_; 63 TPM_HANDLE handle_; 64 void FlushHandleContext(TPM_HANDLE handle); 65 66 DISALLOW_COPY_AND_ASSIGN(ScopedKeyHandle); 67 }; 68 69 } // namespace trunks 70 71 #endif // TRUNKS_SCOPED_KEY_HANDLE_H_ 72