/* * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved. * * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit). * * Use of this source code is governed by MIT-like license that can be found in the * LICENSE file in the root of the source tree. All contributing project authors * may be found in the AUTHORS file in the root of the source tree. */ #include "WebSocketSplitter.h" #include #if !defined(_WIN32) #include #include #endif //!defined(_WIN32) #include "Util/logger.h" #include "Util/util.h" using namespace std; using namespace toolkit; namespace mediakit { /** * 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-------+-+-------------+-------------------------------+ |F|R|R|R| opcode|M| Payload len | Extended payload length | |I|S|S|S| (4) |A| (7) | (16/64) | |N|V|V|V| |S| | (if payload len==126/127) | | |1|2|3| |K| | | +-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - + | Extended payload length continued, if payload len == 127 | + - - - - - - - - - - - - - - - +-------------------------------+ | |Masking-key, if MASK set to 1 | +-------------------------------+-------------------------------+ | Masking-key (continued) | Payload Data | +-------------------------------- - - - - - - - - - - - - - - - + : Payload Data continued ... : + - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + | Payload Data continued ... | +---------------------------------------------------------------+ */ #define CHECK_LEN(size) \ do{ \ if(len - (ptr - data) < size){ \ if(_remain_data.empty()){ \ _remain_data.assign((char *)data,len); \ } \ return ; \ } \ }while(0) \ void WebSocketSplitter::decode(uint8_t *data, size_t len) { uint8_t *ptr = data; if(!_got_header) { // 还没有获取数据头 [AUTO-TRANSLATED:2b50f282] // No data header has been obtained yet if(!_remain_data.empty()){ _remain_data.append((char *)data,len); data = ptr = (uint8_t *)_remain_data.data(); len = _remain_data.size(); } begin_decode: CHECK_LEN(1); _fin = (*ptr & 0x80) >> 7; _reserved = (*ptr & 0x70) >> 4; _opcode = (WebSocketHeader::Type) (*ptr & 0x0F); ptr += 1; CHECK_LEN(1); _mask_flag = (*ptr & 0x80) >> 7; _payload_len = (*ptr & 0x7F); ptr += 1; if (_payload_len == 126) { CHECK_LEN(2); _payload_len = (*ptr << 8) | *(ptr + 1); ptr += 2; } else if (_payload_len == 127) { CHECK_LEN(8); _payload_len = ((uint64_t) ptr[0] << (8 * 7)) | ((uint64_t) ptr[1] << (8 * 6)) | ((uint64_t) ptr[2] << (8 * 5)) | ((uint64_t) ptr[3] << (8 * 4)) | ((uint64_t) ptr[4] << (8 * 3)) | ((uint64_t) ptr[5] << (8 * 2)) | ((uint64_t) ptr[6] << (8 * 1)) | ((uint64_t) ptr[7] << (8 * 0)); ptr += 8; } if (_mask_flag) { CHECK_LEN(4); _mask.assign(ptr, ptr + 4); ptr += 4; } _got_header = true; _mask_offset = 0; _payload_offset = 0; onWebSocketDecodeHeader(*this); if(_payload_len == 0){ onWebSocketDecodeComplete(*this); } } // 进入后面逻辑代表已经获取到了webSocket协议头， [AUTO-TRANSLATED:e6bd2556] // Entering the following logic means that the webSocket protocol header has been obtained, auto remain = len - (ptr - data); if(remain > 0){ auto payload_slice_len = remain; if(payload_slice_len + _payload_offset > _payload_len){ payload_slice_len = _payload_len - _payload_offset; } _payload_offset += payload_slice_len; onPayloadData(ptr, payload_slice_len); if(_payload_offset == _payload_len){ onWebSocketDecodeComplete(*this); // 这是下一个包 [AUTO-TRANSLATED:bf657413] // This is the next package remain -= payload_slice_len; ptr += payload_slice_len; _got_header = false; if(remain > 0){ // 剩余数据是下一个包，把它的数据放置在缓存中 [AUTO-TRANSLATED:7b2ebfad] // The remaining data is the next package, place its data in the cache string str((char *)ptr,remain); _remain_data = str; data = ptr = (uint8_t *)_remain_data.data(); len = _remain_data.size(); goto begin_decode; } } } _remain_data.clear(); } void WebSocketSplitter::onPayloadData(uint8_t *data, size_t len) { if(_mask_flag){ for(size_t i = 0; i < len ; ++i,++data){ *(data) ^= _mask[(i + _mask_offset) % 4]; } _mask_offset = (_mask_offset + len) % 4; } onWebSocketDecodePayload(*this, _mask_flag ? data - len : data, len, _payload_offset); } void WebSocketSplitter::encode(const WebSocketHeader &header,const Buffer::Ptr &buffer) { string ret; uint64_t len = buffer ? buffer->size() : 0; uint8_t byte = header._fin << 7 | ((header._reserved & 0x07) << 4) | (header._opcode & 0x0F) ; ret.push_back(byte); auto mask_flag = (header._mask_flag && header._mask.size() >= 4); byte = mask_flag << 7; if(len < 126){ byte |= len; ret.push_back(byte); }else if(len <= 0xFFFF){ byte |= 126; ret.push_back(byte); uint16_t len_low = htons((uint16_t)len); ret.append((char *)&len_low,2); }else{ byte |= 127; ret.push_back(byte); uint32_t len_high = htonl(len >> 32) ; uint32_t len_low = htonl(len & 0xFFFFFFFF); ret.append((char *)&len_high,4); ret.append((char *)&len_low,4); } if(mask_flag){ ret.append((char *)header._mask.data(),4); } onWebSocketEncodeData(std::make_shared(std::move(ret))); if(len > 0){ if(mask_flag){ uint8_t *ptr = (uint8_t*)buffer->data(); for(size_t i = 0; i < len ; ++i,++ptr){ *(ptr) ^= header._mask[i % 4]; } } onWebSocketEncodeData(buffer); } } } /* namespace mediakit */