WebSocketImpl* WebSocket::completeHandshake(HTTPClientSession& cs, HTTPResponse& response, const std::string& key)
{
std::string connection = response.get("Connection", "");
if (Poco::icompare(connection, "Upgrade") != 0)
throw WebSocketException("No Connection: Upgrade header in handshake response", WS_ERR_NO_HANDSHAKE);
std::string upgrade = response.get("Upgrade", "");
if (Poco::icompare(upgrade, "websocket") != 0)
throw WebSocketException("No Upgrade: websocket header in handshake response", WS_ERR_NO_HANDSHAKE);
std::string accept = response.get("Sec-WebSocket-Accept", "");
if (accept != computeAccept(key))
throw WebSocketException("Invalid or missing Sec-WebSocket-Accept header in handshake response", WS_ERR_NO_HANDSHAKE);
return new WebSocketImpl(static_cast<StreamSocketImpl*>(cs.socket().impl()), true);
}
std::string WebSocketClientHeaderIETF_HYBI17::generateResponse(unsigned short port, const char *webSocketServerProtocolName)
{
bool secureFlag = false;
std::string::size_type pos;
std::string message;
auto secWebSocketKeyIterator = fields.find("Sec-WebSocket-Key");
if(secWebSocketKeyIterator == fields.end())
{
throw WebSocketException("No `Sec-WebSocket-Key` header found");
}
std::string secWebSocketAccept = (*secWebSocketKeyIterator).second + std::string("258EAFA5-E914-47DA-95CA-C5AB0DC85B11");
secWebSocketAccept = StringUtil::SHA1(secWebSocketAccept);
secWebSocketAccept = StringUtil::base64Encode(secWebSocketAccept);
message.append("HTTP/1.1 101 Switching Protocols\r\n");
message.append("Upgrade: WebSocket\r\n");
message.append("Connection: Upgrade\r\n");
message.append(std::string("Sec-WebSocket-Accept: ") + secWebSocketAccept + std::string("\r\n"));
message.append((webSocketServerProtocolName ? (std::string("Sec-WebSocket-Protocol: ") + std::string(webSocketServerProtocolName) + std::string("\r\n")) : ""));
message.append("\r\n");
return message;
}
void WebSocketClientHeaderIETF_HYBI17::read(std::string &packet)
{
std::string line;
std::string::size_type startPos = 0, crlfPos;
line = WebSocketClientHeader::getLine(packet, startPos, crlfPos);
readFirstLine(line);
//Read all of the fields. Field ending is denoted by a pair of CRLF.
startPos = crlfPos + 2;
do {
line = WebSocketClientHeader::getLine(packet, startPos, crlfPos);
readFieldLine(line);
startPos = crlfPos + 2;
if( (startPos + 2) > packet.size() ) {
throw WebSocketException(INVALID_HEADER_EXCEPTION_MESSAGE);
}
} while(packet[startPos] != '\r' && packet[startPos + 1] != '\n');
//Skip over the last crlf.
startPos += 2;
packet.erase(0, startPos);
}
WebSocketImpl* WebSocket::connect(HTTPClientSession& cs, HTTPRequest& request, HTTPResponse& response, HTTPCredentials& credentials)
{
if (!cs.getProxyHost().empty() && !cs.secure())
{
cs.proxyTunnel();
}
std::string key = createKey();
request.set("Connection", "Upgrade");
request.set("Upgrade", "websocket");
request.set("Sec-WebSocket-Version", WEBSOCKET_VERSION);
request.set("Sec-WebSocket-Key", key);
request.setChunkedTransferEncoding(false);
cs.setKeepAlive(true);
cs.sendRequest(request);
std::istream& istr = cs.receiveResponse(response);
if (response.getStatus() == HTTPResponse::HTTP_SWITCHING_PROTOCOLS)
{
return completeHandshake(cs, response, key);
}
else if (response.getStatus() == HTTPResponse::HTTP_UNAUTHORIZED)
{
Poco::NullOutputStream null;
Poco::StreamCopier::copyStream(istr, null);
credentials.authenticate(request, response);
if (!cs.getProxyHost().empty() && !cs.secure())
{
cs.reset();
cs.proxyTunnel();
}
cs.sendRequest(request);
cs.receiveResponse(response);
if (response.getStatus() == HTTPResponse::HTTP_SWITCHING_PROTOCOLS)
{
return completeHandshake(cs, response, key);
}
else if (response.getStatus() == HTTPResponse::HTTP_UNAUTHORIZED)
{
throw WebSocketException("Not authorized", WS_ERR_UNAUTHORIZED);
}
}
throw WebSocketException("Cannot upgrade to WebSocket connection", response.getReason(), WS_ERR_NO_HANDSHAKE);
}
WebSocketImpl* WebSocket::accept(HTTPServerRequest& request, HTTPServerResponse& response)
{
if (icompare(request.get("Connection", ""), "Upgrade") == 0 &&
icompare(request.get("Upgrade", ""), "websocket") == 0)
{
std::string version = request.get("Sec-WebSocket-Version", "");
if (version.empty()) throw WebSocketException("Missing Sec-WebSocket-Version in handshake request", WS_ERR_HANDSHAKE_NO_VERSION);
if (version != WEBSOCKET_VERSION) throw WebSocketException("Unsupported WebSocket version requested", version, WS_ERR_HANDSHAKE_UNSUPPORTED_VERSION);
std::string key = request.get("Sec-WebSocket-Key", "");
Poco::trimInPlace(key);
if (key.empty()) throw WebSocketException("Missing Sec-WebSocket-Key in handshake request", WS_ERR_HANDSHAKE_NO_KEY);
response.setStatusAndReason(HTTPResponse::HTTP_SWITCHING_PROTOCOLS);
response.set("Upgrade", "websocket");
response.set("Connection", "Upgrade");
response.set("Sec-WebSocket-Accept", computeAccept(key));
response.setContentLength(0);
response.send().flush();
return new WebSocketImpl(static_cast<StreamSocketImpl*>(static_cast<HTTPServerRequestImpl&>(request).detachSocket().impl()), false);
}
else throw WebSocketException("No WebSocket handshake", WS_ERR_NO_HANDSHAKE);
}
