| 120 | |
| 121 | |
| 122 | bool KeybufManager::EnterInternal() |
| 123 | { |
| 124 | |
| 125 | lock_guard<mutex> lock(m_mutex); |
| 126 | |
| 127 | assert(m_refcount >= 0); |
| 128 | |
| 129 | m_refcount++; |
| 130 | |
| 131 | if (m_refcount > 1) { |
| 132 | return true; |
| 133 | } |
| 134 | |
| 135 | if (m_key_cache_id) { |
| 136 | bool result = KeyCache::GetInstance()->Retrieve(m_key_cache_id, m_bufs); |
| 137 | if (result) { |
| 138 | return true; |
| 139 | } |
| 140 | } |
| 141 | |
| 142 | DATA_BLOB key_blob; |
| 143 | DATA_BLOB enc_key_blob; |
| 144 | |
| 145 | DATA_BLOB optional_entropy; |
| 146 | optional_entropy.cbData = static_cast<DWORD>(sizeof(m_optional_entropy)); |
| 147 | optional_entropy.pbData = m_optional_entropy; |
| 148 | |
| 149 | enc_key_blob.cbData = static_cast<DWORD>(m_encryptedBuf.size()); |
| 150 | enc_key_blob.pbData = &m_encryptedBuf[0]; |
| 151 | |
| 152 | BOOL bResult = CryptUnprotectData(&enc_key_blob, NULL, &optional_entropy, NULL, NULL, 0, &key_blob); |
| 153 | |
| 154 | if (!bResult) |
| 155 | throw std::exception("KeybufManager unable to decrypt keys"); |
| 156 | |
| 157 | if (key_blob.cbData != m_total_len) { |
| 158 | SecureZeroMemory(key_blob.pbData, key_blob.cbData); |
| 159 | LocalFree(key_blob.pbData); |
| 160 | throw std::exception("KeybufManager decrypted wrong number of bytes"); |
| 161 | } |
| 162 | |
| 163 | KeyBuf::CopyBuffers(m_bufs, key_blob.pbData, key_blob.cbData); |
| 164 | |
| 165 | if (m_key_cache_id) { |
| 166 | KeyCache::GetInstance()->Store(m_key_cache_id, key_blob.pbData, key_blob.cbData); |
| 167 | } |
| 168 | |
| 169 | SecureZeroMemory(key_blob.pbData, key_blob.cbData); |
| 170 | LocalFree(key_blob.pbData); |
| 171 | |
| 172 | return bResult; |
| 173 | } |
| 174 | |
| 175 | void KeybufManager::LeaveInternal() |
| 176 | { |