| /* |
| * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| // @file Contains utility classes that make it easier to use SecBuffers |
| |
| #ifndef WEBRTC_BASE_SEC_BUFFER_H__ |
| #define WEBRTC_BASE_SEC_BUFFER_H__ |
| |
| namespace rtc { |
| |
| // A base class for CSecBuffer<T>. Contains |
| // all implementation that does not require |
| // template arguments. |
| class CSecBufferBase : public SecBuffer { |
| public: |
| CSecBufferBase() { |
| Clear(); |
| } |
| |
| // Uses the SSPI to free a pointer, must be |
| // used for buffers returned from SSPI APIs. |
| static void FreeSSPI(void *ptr) { |
| if ( ptr ) { |
| SECURITY_STATUS status; |
| status = ::FreeContextBuffer(ptr); |
| ASSERT(SEC_E_OK == status); // "Freeing context buffer" |
| } |
| } |
| |
| // Deletes a buffer with operator delete |
| static void FreeDelete(void *ptr) { |
| delete [] reinterpret_cast<char*>(ptr); |
| } |
| |
| // A noop delete, for buffers over other |
| // people's memory |
| static void FreeNone(void *ptr) { |
| } |
| |
| protected: |
| // Clears the buffer to EMPTY & NULL |
| void Clear() { |
| this->BufferType = SECBUFFER_EMPTY; |
| this->cbBuffer = 0; |
| this->pvBuffer = NULL; |
| } |
| }; |
| |
| // Wrapper class for SecBuffer to take care |
| // of initialization and destruction. |
| template <void (*pfnFreeBuffer)(void *ptr)> |
| class CSecBuffer: public CSecBufferBase { |
| public: |
| // Initializes buffer to empty & NULL |
| CSecBuffer() { |
| } |
| |
| // Frees any allocated memory |
| ~CSecBuffer() { |
| Release(); |
| } |
| |
| // Frees the buffer appropriately, and re-nulls |
| void Release() { |
| pfnFreeBuffer(this->pvBuffer); |
| Clear(); |
| } |
| |
| // This class must not extend the size of SecBuffer, since we use arrays of |
| // CSecBuffer in CSecBufferBundle below. |
| static_assert(sizeof(CSecBuffer<pfnFreeBuffer>) == sizeof(SecBuffer), ""); |
| }; |
| |
| // Contains all generic implementation for the |
| // SecBufferBundle class |
| class SecBufferBundleBase { |
| public: |
| }; |
| |
| // A template class that bundles a SecBufferDesc with |
| // one or more SecBuffers for convenience. Can take |
| // care of deallocating buffers appropriately, as indicated |
| // by pfnFreeBuffer function. |
| // By default does no deallocation. |
| template <int num_buffers, |
| void (*pfnFreeBuffer)(void *ptr) = CSecBufferBase::FreeNone> |
| class CSecBufferBundle : public SecBufferBundleBase { |
| public: |
| // Constructs a security buffer bundle with num_buffers |
| // buffers, all of which are empty and nulled. |
| CSecBufferBundle() { |
| desc_.ulVersion = SECBUFFER_VERSION; |
| desc_.cBuffers = num_buffers; |
| desc_.pBuffers = buffers_; |
| } |
| |
| // Frees all currently used buffers. |
| ~CSecBufferBundle() { |
| Release(); |
| } |
| |
| // Accessor for the descriptor |
| PSecBufferDesc desc() { |
| return &desc_; |
| } |
| |
| // Accessor for the descriptor |
| PSecBufferDesc desc() const { |
| return &desc_; |
| } |
| |
| // returns the i-th security buffer |
| SecBuffer &operator[] (size_t num) { |
| ASSERT(num < num_buffers); // "Buffer index out of bounds" |
| return buffers_[num]; |
| } |
| |
| // returns the i-th security buffer |
| const SecBuffer &operator[] (size_t num) const { |
| ASSERT(num < num_buffers); // "Buffer index out of bounds" |
| return buffers_[num]; |
| } |
| |
| // Frees all non-NULL security buffers, |
| // using the deallocation function |
| void Release() { |
| for ( size_t i = 0; i < num_buffers; ++i ) { |
| buffers_[i].Release(); |
| } |
| } |
| |
| private: |
| // Our descriptor |
| SecBufferDesc desc_; |
| // Our bundled buffers, each takes care of its own |
| // initialization and destruction |
| CSecBuffer<pfnFreeBuffer> buffers_[num_buffers]; |
| }; |
| |
| } // namespace rtc |
| |
| #endif // WEBRTC_BASE_SEC_BUFFER_H__ |