| /* |
| * Copyright (C) 2021 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include <snapuserd/snapuserd_buffer.h> |
| #include <snapuserd/snapuserd_kernel.h> |
| |
| namespace android { |
| namespace snapshot { |
| |
| void BufferSink::Initialize(size_t size) { |
| buffer_size_ = size; |
| buffer_offset_ = 0; |
| buffer_ = std::make_unique<uint8_t[]>(size); |
| } |
| |
| void* BufferSink::GetPayloadBuffer(size_t size) { |
| if ((buffer_size_ - buffer_offset_) < size) return nullptr; |
| |
| char* buffer = reinterpret_cast<char*>(GetBufPtr()); |
| struct dm_user_message* msg = (struct dm_user_message*)(&(buffer[0])); |
| return (char*)msg->payload.buf + buffer_offset_; |
| } |
| |
| void* BufferSink::GetBuffer(size_t requested, size_t* actual) { |
| void* buf = GetPayloadBuffer(requested); |
| if (!buf) { |
| *actual = 0; |
| return nullptr; |
| } |
| *actual = requested; |
| return buf; |
| } |
| |
| struct dm_user_header* BufferSink::GetHeaderPtr() { |
| if (!(sizeof(struct dm_user_header) <= buffer_size_)) { |
| return nullptr; |
| } |
| char* buf = reinterpret_cast<char*>(GetBufPtr()); |
| struct dm_user_header* header = (struct dm_user_header*)(&(buf[0])); |
| return header; |
| } |
| |
| void* BufferSink::GetPayloadBufPtr() { |
| char* buffer = reinterpret_cast<char*>(GetBufPtr()); |
| struct dm_user_message* msg = reinterpret_cast<struct dm_user_message*>(&(buffer[0])); |
| return msg->payload.buf; |
| } |
| |
| void XorSink::Initialize(BufferSink* sink, size_t size) { |
| bufsink_ = sink; |
| buffer_size_ = size; |
| returned_ = 0; |
| buffer_ = std::make_unique<uint8_t[]>(size); |
| } |
| |
| void XorSink::Reset() { |
| returned_ = 0; |
| } |
| |
| void* XorSink::GetBuffer(size_t requested, size_t* actual) { |
| if (requested > buffer_size_) { |
| *actual = buffer_size_; |
| } else { |
| *actual = requested; |
| } |
| return buffer_.get(); |
| } |
| |
| bool XorSink::ReturnData(void* buffer, size_t len) { |
| uint8_t* xor_data = reinterpret_cast<uint8_t*>(buffer); |
| uint8_t* buff = reinterpret_cast<uint8_t*>(bufsink_->GetPayloadBuffer(len + returned_)); |
| if (buff == nullptr) { |
| return false; |
| } |
| for (size_t i = 0; i < len; i++) { |
| buff[returned_ + i] ^= xor_data[i]; |
| } |
| returned_ += len; |
| return true; |
| } |
| |
| } // namespace snapshot |
| } // namespace android |