/*
* IXWebSocketTransport.cpp
* Author: Benjamin Sergeant
* Copyright (c) 2017-2018 Machine Zone, Inc. All rights reserved.
*/
//
// Adapted from https://github.com/dhbaird/easywsclient
//
#include "IXWebSocketTransport.h"
#include "IXSocket.h"
#ifdef __APPLE__
# include "IXSocketAppleSSL.h"
#else
# include "IXSocketOpenSSL.h"
#endif
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <cstdlib>
#include <vector>
#include <string>
#include <cstdarg>
#include <iostream>
#include <sstream>
#include <regex>
namespace ix {
WebSocketTransport::WebSocketTransport() :
_readyState(CLOSED)
{
;
}
WebSocketTransport::~WebSocketTransport()
{
;
}
void WebSocketTransport::configure(const std::string& url)
{
_url = url;
}
bool WebSocketTransport::parseUrl(const std::string& url,
std::string& protocol,
std::string& host,
std::string& path,
std::string& query,
int& port)
{
std::regex ex("(ws|wss)://([^/ :]+):?([^/ ]*)(/?[^ #?]*)\\x3f?([^ #]*)#?([^ ]*)");
std::cmatch what;
if (!regex_match(url.c_str(), what, ex))
{
return false;
}
std::string portStr;
protocol = std::string(what[1].first, what[1].second);
host = std::string(what[2].first, what[2].second);
portStr = std::string(what[3].first, what[3].second);
path = std::string(what[4].first, what[4].second);
query = std::string(what[5].first, what[5].second);
if (portStr.empty())
{
if (protocol == "ws")
{
port = 80;
}
else if (protocol == "wss")
{
port = 443;
}
}
else
{
std::stringstream ss;
ss << portStr;
ss >> port;
}
if (path.empty())
{
path = "/";
}
else if (path[0] != '/')
{
path = '/' + path;
}
if (!query.empty())
{
path += "?";
path += query;
}
return true;
}
void WebSocketTransport::printUrl(const std::string& url)
{
std::string protocol, host, path, query;
int port {0};
if (!WebSocketTransport::parseUrl(url, protocol, host,
path, query, port))
{
return;
}
std::cout << "[" << url << "]" << std::endl;
std::cout << protocol << std::endl;
std::cout << host << std::endl;
std::cout << port << std::endl;
std::cout << path << std::endl;
std::cout << query << std::endl;
std::cout << "-------------------------------" << std::endl;
}
WebSocketInitResult WebSocketTransport::init()
{
std::string protocol, host, path, query;
int port;
if (!WebSocketTransport::parseUrl(_url, protocol, host,
path, query, port))
{
return WebSocketInitResult(false, 0, "Could not parse URL");
}
if (protocol == "wss")
{
_socket.reset();
#ifdef __APPLE__
_socket = std::make_shared<SocketAppleSSL>();
#else
_socket = std::make_shared<SocketOpenSSL>();
#endif
}
else
{
_socket.reset();
_socket = std::make_shared<Socket>();
}
std::string errMsg;
bool success = _socket->connect(host, port, errMsg);
if (!success)
{
std::stringstream ss;
ss << "Unable to connect to " << host
<< " on port " << port
<< ", error: " << errMsg;
return WebSocketInitResult(false, 0, ss.str());
}
char line[256];
int status;
int i;
snprintf(line, 256,
"GET %s HTTP/1.1\r\n"
"Host: %s:%d\r\n"
"Upgrade: websocket\r\n"
"Connection: Upgrade\r\n"
"Sec-WebSocket-Key: x3JJHMbDL1EzLkh9GBhXDw==\r\n"
"Sec-WebSocket-Version: 13\r\n"
"\r\n",
path.c_str(), host.c_str(), port);
// XXX: this should be done non-blocking,
size_t lineSize = strlen(line);
if (_socket->send(line, lineSize) != lineSize)
{
return WebSocketInitResult(false, 0, std::string("Failed sending GET request to ") + _url);
}
for (i = 0; i < 2 || (i < 255 && line[i-2] != '\r' && line[i-1] != '\n'); ++i)
{
if (_socket->recv(line+i, 1) == 0)
{
return WebSocketInitResult(false, 0, std::string("Failed reading HTTP status line from ") + _url);
}
}
line[i] = 0;
if (i == 255)
{
return WebSocketInitResult(false, 0, std::string("Got bad status line connecting to ") + _url);
}
// HTTP/1.0 is too old.
if (sscanf(line, "HTTP/1.0 %d", &status) == 1)
{
std::stringstream ss;
ss << "Server version is HTTP/1.0. Rejecting connection to " << host;
return WebSocketInitResult(false, status, ss.str());
}
// We want an 101 HTTP status
if (sscanf(line, "HTTP/1.1 %d", &status) != 1 || status != 101)
{
std::stringstream ss;
ss << "Got bad status connecting to " << host
<< ", status: " << status
<< ", HTTP Status line: " << line;
return WebSocketInitResult(false, status, ss.str());
}
// TODO: verify response headers,
while (true)
{
for (i = 0;
i < 2 || (i < 255 && line[i-2] != '\r' && line[i-1] != '\n');
++i)
{
if (_socket->recv(line+i, 1) == 0)
{
return WebSocketInitResult(false, status, std::string("Failed reading response header from ") + _url);
}
}
if (line[0] == '\r' && line[1] == '\n')
{
break;
}
}
_socket->configure();
setReadyState(OPEN);
return WebSocketInitResult(true, status, "");
}
WebSocketTransport::ReadyStateValues WebSocketTransport::getReadyState() const
{
return _readyState;
}
void WebSocketTransport::setReadyState(ReadyStateValues readyStateValue)
{
_readyState = readyStateValue;
_onStateChangeCallback(readyStateValue);
}
void WebSocketTransport::setOnStateChangeCallback(const OnStateChangeCallback& onStateChangeCallback)
{
_onStateChangeCallback = onStateChangeCallback;
}
void WebSocketTransport::poll()
{
_socket->poll(
[this]()
{
while (true)
{
int N = (int) _rxbuf.size();
ssize_t ret;
_rxbuf.resize(N + 1500);
ret = _socket->recv((char*)&_rxbuf[0] + N, 1500);
if (ret < 0 && (errno == EWOULDBLOCK ||
errno == EAGAIN)) {
_rxbuf.resize(N);
break;
}
else if (ret <= 0)
{
_rxbuf.resize(N);
_socket->close();
setReadyState(CLOSED);
break;
}
else
{
_rxbuf.resize(N + ret);
}
}
if (isSendBufferEmpty() && _readyState == CLOSING)
{
_socket->close();
setReadyState(CLOSED);
}
});
}
bool WebSocketTransport::isSendBufferEmpty() const
{
std::lock_guard<std::mutex> lock(_txbufMutex);
return _txbuf.empty();
}
void WebSocketTransport::appendToSendBuffer(const std::vector<uint8_t>& header,
std::string::const_iterator begin,
std::string::const_iterator end,
uint64_t message_size,
uint8_t masking_key[4])
{
std::lock_guard<std::mutex> lock(_txbufMutex);
_txbuf.insert(_txbuf.end(), header.begin(), header.end());
_txbuf.insert(_txbuf.end(), begin, end);
// Masking
for (size_t i = 0; i != (size_t) message_size; ++i)
{
*(_txbuf.end() - (size_t) message_size + i) ^= masking_key[i&0x3];
}
}
void WebSocketTransport::appendToSendBuffer(const std::vector<uint8_t>& buffer)
{
std::lock_guard<std::mutex> lock(_txbufMutex);
_txbuf.insert(_txbuf.end(), buffer.begin(), buffer.end());
}
//
// http://tools.ietf.org/html/rfc6455#section-5.2 Base Framing Protocol
//
// 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 ... |
// +---------------------------------------------------------------+
//
void WebSocketTransport::dispatch(const OnMessageCallback& onMessageCallback)
{
// TODO: consider acquiring a lock on _rxbuf...
while (true) {
wsheader_type ws;
if (_rxbuf.size() < 2) return; /* Need at least 2 */
const uint8_t * data = (uint8_t *) &_rxbuf[0]; // peek, but don't consume
ws.fin = (data[0] & 0x80) == 0x80;
ws.opcode = (wsheader_type::opcode_type) (data[0] & 0x0f);
ws.mask = (data[1] & 0x80) == 0x80;
ws.N0 = (data[1] & 0x7f);
ws.header_size = 2 + (ws.N0 == 126? 2 : 0) + (ws.N0 == 127? 8 : 0) + (ws.mask? 4 : 0);
if (_rxbuf.size() < ws.header_size) return; /* Need: ws.header_size - _rxbuf.size() */
//
// Calculate payload length:
// 0-125 mean the payload is that long.
// 126 means that the following two bytes indicate the length,
// 127 means the next 8 bytes indicate the length.
//
int i = 0;
if (ws.N0 < 126)
{
ws.N = ws.N0;
i = 2;
}
else if (ws.N0 == 126)
{
ws.N = 0;
ws.N |= ((uint64_t) data[2]) << 8;
ws.N |= ((uint64_t) data[3]) << 0;
i = 4;
}
else if (ws.N0 == 127)
{
ws.N = 0;
ws.N |= ((uint64_t) data[2]) << 56;
ws.N |= ((uint64_t) data[3]) << 48;
ws.N |= ((uint64_t) data[4]) << 40;
ws.N |= ((uint64_t) data[5]) << 32;
ws.N |= ((uint64_t) data[6]) << 24;
ws.N |= ((uint64_t) data[7]) << 16;
ws.N |= ((uint64_t) data[8]) << 8;
ws.N |= ((uint64_t) data[9]) << 0;
i = 10;
}
else
{
// invalid payload length according to the spec. bail out
return;
}
if (ws.mask)
{
ws.masking_key[0] = ((uint8_t) data[i+0]) << 0;
ws.masking_key[1] = ((uint8_t) data[i+1]) << 0;
ws.masking_key[2] = ((uint8_t) data[i+2]) << 0;
ws.masking_key[3] = ((uint8_t) data[i+3]) << 0;
}
else
{
ws.masking_key[0] = 0;
ws.masking_key[1] = 0;
ws.masking_key[2] = 0;
ws.masking_key[3] = 0;
}
if (_rxbuf.size() < ws.header_size+ws.N)
{
return; /* Need: ws.header_size+ws.N - _rxbuf.size() */
}
// We got a whole message, now do something with it:
if (
ws.opcode == wsheader_type::TEXT_FRAME
|| ws.opcode == wsheader_type::BINARY_FRAME
|| ws.opcode == wsheader_type::CONTINUATION
) {
if (ws.mask)
{
for (size_t j = 0; j != ws.N; ++j)
{
_rxbuf[j+ws.header_size] ^= ws.masking_key[j&0x3];
}
}
_receivedData.insert(_receivedData.end(),
_rxbuf.begin()+ws.header_size,
_rxbuf.begin()+ws.header_size+(size_t)ws.N);// just feed
if (ws.fin)
{
// fire callback with a string message
std::string stringMessage(_receivedData.begin(),
_receivedData.end());
onMessageCallback(stringMessage);
_receivedData.clear();
}
}
else if (ws.opcode == wsheader_type::PING)
{
if (ws.mask)
{
for (size_t j = 0; j != ws.N; ++j)
{
_rxbuf[j+ws.header_size] ^= ws.masking_key[j&0x3];
}
}
std::string pingData(_rxbuf.begin()+ws.header_size,
_rxbuf.begin()+ws.header_size + (size_t) ws.N);
sendData(wsheader_type::PONG, pingData.size(),
pingData.begin(), pingData.end());
}
else if (ws.opcode == wsheader_type::PONG) { }
else if (ws.opcode == wsheader_type::CLOSE) { close(); }
else { close(); }
_rxbuf.erase(_rxbuf.begin(),
_rxbuf.begin() + ws.header_size + (size_t) ws.N);
}
}
unsigned WebSocketTransport::getRandomUnsigned()
{
auto now = std::chrono::system_clock::now();
auto seconds =
std::chrono::duration_cast<std::chrono::seconds>(
now.time_since_epoch()).count();
return static_cast<unsigned>(seconds);
}
void WebSocketTransport::sendData(wsheader_type::opcode_type type,
uint64_t message_size,
std::string::const_iterator message_begin,
std::string::const_iterator message_end)
{
if (_readyState == CLOSING || _readyState == CLOSED)
{
return;
}
unsigned x = getRandomUnsigned();
uint8_t masking_key[4] = {};
masking_key[0] = (x >> 24);
masking_key[1] = (x >> 16) & 0xff;
masking_key[2] = (x >> 8) & 0xff;
masking_key[3] = (x) & 0xff;
std::vector<uint8_t> header;
header.assign(2 +
(message_size >= 126 ? 2 : 0) +
(message_size >= 65536 ? 6 : 0) + 4, 0);
header[0] = 0x80 | type;
if (message_size < 126)
{
header[1] = (message_size & 0xff) | 0x80;
header[2] = masking_key[0];
header[3] = masking_key[1];
header[4] = masking_key[2];
header[5] = masking_key[3];
}
else if (message_size < 65536)
{
header[1] = 126 | 0x80;
header[2] = (message_size >> 8) & 0xff;
header[3] = (message_size >> 0) & 0xff;
header[4] = masking_key[0];
header[5] = masking_key[1];
header[6] = masking_key[2];
header[7] = masking_key[3];
}
else
{ // TODO: run coverage testing here
header[1] = 127 | 0x80;
header[2] = (message_size >> 56) & 0xff;
header[3] = (message_size >> 48) & 0xff;
header[4] = (message_size >> 40) & 0xff;
header[5] = (message_size >> 32) & 0xff;
header[6] = (message_size >> 24) & 0xff;
header[7] = (message_size >> 16) & 0xff;
header[8] = (message_size >> 8) & 0xff;
header[9] = (message_size >> 0) & 0xff;
header[10] = masking_key[0];
header[11] = masking_key[1];
header[12] = masking_key[2];
header[13] = masking_key[3];
}
// _txbuf will keep growing until it can be transmitted over the socket:
appendToSendBuffer(header, message_begin, message_end,
message_size, masking_key);
// Now actually send this data
sendOnSocket();
}
void WebSocketTransport::sendPing()
{
std::string empty;
sendData(wsheader_type::PING, empty.size(), empty.begin(), empty.end());
}
void WebSocketTransport::sendBinary(const std::string& message)
{
sendData(wsheader_type::BINARY_FRAME, message.size(), message.begin(), message.end());
}
void WebSocketTransport::sendOnSocket()
{
std::lock_guard<std::mutex> lock(_txbufMutex);
while (_txbuf.size())
{
int ret = _socket->send((char*)&_txbuf[0], _txbuf.size());
if (ret < 0 && (errno == EWOULDBLOCK ||
errno == EAGAIN))
{
break;
}
else if (ret <= 0)
{
_socket->close();
setReadyState(CLOSED);
break;
}
else
{
_txbuf.erase(_txbuf.begin(), _txbuf.begin() + ret);
}
}
}
void WebSocketTransport::close()
{
if (_readyState == CLOSING || _readyState == CLOSED) return;
setReadyState(CLOSING);
uint8_t closeFrame[6] = {0x88, 0x80, 0x00, 0x00, 0x00, 0x00}; // last 4 bytes are a masking key
std::vector<uint8_t> header(closeFrame, closeFrame+6);
appendToSendBuffer(header);
sendOnSocket();
_socket->wakeUpFromPoll();
}
} // namespace ix