Harden client and WebSocket proxy

This commit is contained in:
2026-09-09 13:04:56 +02:00
parent f4f95ffff4
commit 8986f6270f
64 changed files with 4410 additions and 7313 deletions
+267 -465
View File
@@ -1,491 +1,293 @@
import { WebSocketServer } from 'ws';
import * as net from 'net';
import * as tls from 'tls';
import http from 'http';
import { parse } from 'url';
import { randomBytes } from 'node:crypto';
import { lookup } from 'node:dns/promises';
import http from 'node:http';
import net, { BlockList } from 'node:net';
import tls from 'node:tls';
import { WebSocket, WebSocketServer } from 'ws';
// Default configuration for connection persistence (fallback values)
const DEFAULT_PERSISTENCE_TIMEOUT = 5 * 60 * 1000; // 5 minutes in milliseconds
const DEFAULT_MAX_BUFFER_MESSAGES = 100; // Maximum number of messages to buffer
const DEFAULT_MAX_BUFFER_SIZE_KB = 10; // Maximum buffer size in KB
const PORT = numberFromEnv('WS_PORT', 3001, 1, 65535);
const MAX_SESSIONS_PER_IP = numberFromEnv('PROXY_MAX_SESSIONS_PER_IP', 3, 1, 20);
const MAX_GLOBAL_SESSIONS = numberFromEnv('PROXY_MAX_GLOBAL_SESSIONS', 200, 1, 10_000);
const NEW_CONNECTION_LIMIT = numberFromEnv('PROXY_NEW_CONNECTIONS_PER_10_MIN', 20, 1, 1_000);
const CONNECT_TIMEOUT_MS = 10_000;
const PERSISTENCE_TIMEOUT_MS = 5 * 60_000;
const MAX_BUFFER_MESSAGES = 250;
const MAX_BUFFER_BYTES = 256 * 1024;
const MAX_CONTROL_BYTES = 4 * 1024;
const MAX_BYTES_PER_SECOND = 2 * 1024 * 1024;
const DENIED_PORTS = new Set([25, 465, 587, 2525]);
const production = process.env.NODE_ENV === 'production';
const allowedOrigins = new Set(
(process.env.ALLOWED_ORIGINS || (production ? '' : 'http://localhost:5173,http://127.0.0.1:5173'))
.split(',').map((origin) => origin.trim()).filter(Boolean)
);
const deniedAddresses = createDeniedAddressList();
const sessions = new Map();
const connectionAttempts = new Map();
const HEARTBEAT_INTERVAL = 30 * 1000; // 30 seconds
// Create HTTP server
const server = http.createServer();
// Create WebSocket server
const wss = new WebSocketServer({ noServer: true });
// Active connections and their proxies
// Key: connectionId, Value: { ws, socket, sessionId, settings }
const connections = new Map();
// Persistent connections waiting for reconnection
// Key: sessionId, Value: { socket, mudHost, mudPort, useSSL, timeoutId, lastActivity, messageBuffer, settings }
const persistentConnections = new Map();
// Parse connection settings from URL parameters with defaults
function parseConnectionSettings(urlParts) {
const persistenceTimeoutParam = urlParts.searchParams.get('persistenceTimeout');
const maxBufferMessagesParam = urlParts.searchParams.get('maxBufferMessages');
const maxBufferSizeKBParam = urlParts.searchParams.get('maxBufferSizeKB');
return {
persistenceTimeoutMs: persistenceTimeoutParam ?
parseInt(persistenceTimeoutParam) * 60 * 1000 : // Convert minutes to milliseconds
DEFAULT_PERSISTENCE_TIMEOUT,
maxBufferMessages: maxBufferMessagesParam ?
parseInt(maxBufferMessagesParam) :
DEFAULT_MAX_BUFFER_MESSAGES,
maxBufferSizeKB: maxBufferSizeKBParam ?
parseInt(maxBufferSizeKBParam) :
DEFAULT_MAX_BUFFER_SIZE_KB
};
}
// Generate a unique session ID for persistent connections
function generateSessionId() {
return `session-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
}
// Buffer a message for a persistent connection
function bufferMessage(sessionId, data) {
const persistentConn = persistentConnections.get(sessionId);
if (!persistentConn) {
return; // No persistent connection to buffer for
}
if (!persistentConn.messageBuffer) {
persistentConn.messageBuffer = [];
persistentConn.bufferSize = 0;
}
// Add timestamp to the message
const bufferedMessage = {
data: data,
timestamp: Date.now()
};
persistentConn.messageBuffer.push(bufferedMessage);
persistentConn.bufferSize += data.length;
// Use this connection's specific settings for buffer limits
const settings = persistentConn.settings || {
maxBufferMessages: DEFAULT_MAX_BUFFER_MESSAGES,
maxBufferSizeKB: DEFAULT_MAX_BUFFER_SIZE_KB
};
// Trim buffer if it gets too large
while (persistentConn.messageBuffer.length > settings.maxBufferMessages ||
persistentConn.bufferSize > settings.maxBufferSizeKB * 1000) {
const removed = persistentConn.messageBuffer.shift();
if (removed) {
persistentConn.bufferSize -= removed.data.length;
}
}
console.log(`Buffered ${data.length} bytes for session ${sessionId} (${persistentConn.messageBuffer.length} messages, ${persistentConn.bufferSize} bytes total, limits: ${settings.maxBufferMessages} msgs/${settings.maxBufferSizeKB}KB)`);
}
// Replay buffered messages to a reconnected client
function replayBufferedMessages(ws, sessionId) {
const persistentConn = persistentConnections.get(sessionId);
if (!persistentConn || !persistentConn.messageBuffer) {
return 0; // No messages to replay
}
const messages = persistentConn.messageBuffer;
console.log(`Replaying ${messages.length} buffered messages for session ${sessionId}`);
// Send a notification about message replay
const replayNotification = `[SYSTEM]${JSON.stringify({
type: 'message_replay_start',
messageCount: messages.length,
timespan: messages.length > 0 ? Date.now() - messages[0].timestamp : 0
})}`;
ws.send(replayNotification);
// Send all buffered messages
for (const message of messages) {
if (ws.readyState === 1) { // WebSocket.OPEN
ws.send(message.data);
}
}
// Send replay complete notification
const replayComplete = `[SYSTEM]${JSON.stringify({ type: 'message_replay_complete' })}`;
ws.send(replayComplete);
// Clear the buffer since messages have been replayed
const messageCount = messages.length;
persistentConn.messageBuffer = [];
persistentConn.bufferSize = 0;
return messageCount;
}
// Clean up a persistent connection
function cleanupPersistentConnection(sessionId) {
const persistentConn = persistentConnections.get(sessionId);
if (persistentConn) {
console.log(`Cleaning up persistent connection for session ${sessionId}`);
// Clear timeout
if (persistentConn.timeoutId) {
clearTimeout(persistentConn.timeoutId);
}
// Close MUD socket
if (persistentConn.socket && !persistentConn.socket.destroyed) {
persistentConn.socket.end();
}
// Remove from map
persistentConnections.delete(sessionId);
}
}
// Handle WebSocket connections
wss.on('connection', (ws, req, mudHost, mudPort, useSSL) => {
console.log(`WebSocket connection established for ${mudHost}:${mudPort} (SSL: ${useSSL})`);
// Create a unique ID for this connection
const connectionId = `${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
// Check for session ID and settings in query parameters
const url = req.url || '';
const urlParts = new URL(`http://localhost${url}`);
const sessionId = urlParts.searchParams.get('sessionId');
// Parse connection settings for this specific connection
const connectionSettings = parseConnectionSettings(urlParts);
console.log(`Connection settings for ${connectionId}: timeout=${connectionSettings.persistenceTimeoutMs/1000/60}min, maxMessages=${connectionSettings.maxBufferMessages}, maxSizeKB=${connectionSettings.maxBufferSizeKB}`);
// Special handling for test connections
if (mudHost === 'example.com' && mudPort === '23') {
console.log('Test connection detected - using echo server mode');
// Send welcome message
ws.send('Hello from WebSocket test server! This is an echo server.');
// Echo back messages
ws.on('message', (message) => {
console.log('Test server received:', message.toString());
ws.send(`Echo: ${message.toString()}`);
});
// Handle close
ws.on('close', () => {
console.log('Test connection closed');
connections.delete(connectionId);
});
// Store the connection (without a socket)
connections.set(connectionId, { ws, testMode: true });
const server = http.createServer((request, response) => {
if (request.url === '/health') {
response.writeHead(200, { 'content-type': 'application/json' });
response.end(JSON.stringify({ ok: true, sessions: sessions.size }));
return;
}
response.writeHead(404);
response.end();
});
const wss = new WebSocketServer({ noServer: true, maxPayload: 64 * 1024, perMessageDeflate: false });
let socket;
let currentSessionId = sessionId;
// Check if this is a reconnection to an existing persistent session
if (sessionId && persistentConnections.has(sessionId)) {
console.log(`Reconnecting to existing session: ${sessionId}`);
const persistentConn = persistentConnections.get(sessionId);
socket = persistentConn.socket;
// Clear the timeout since client reconnected
if (persistentConn.timeoutId) {
clearTimeout(persistentConn.timeoutId);
}
// Replay any buffered messages first
const replayedCount = replayBufferedMessages(ws, sessionId);
// Remove from persistent connections (now active again) - do this after replay
persistentConnections.delete(sessionId);
// Send reconnection notification with session ID in proper JSON format
ws.send(`[SYSTEM]${JSON.stringify({
type: 'session_resumed',
sessionId: sessionId,
messagesReplayed: replayedCount
})}`);
} else {
// Create new connection
currentSessionId = generateSessionId();
console.log(`Creating new session: ${currentSessionId}`);
try {
// Create a TCP socket connection to the MUD server
// Use tls for SSL connections, net for regular connections
socket = useSSL
? tls.connect({ host: mudHost, port: parseInt(mudPort), rejectUnauthorized: false })
: net.createConnection({ host: mudHost, port: parseInt(mudPort) });
// Add error handler
socket.on('error', (error) => {
console.error(`Socket error for ${mudHost}:${mudPort}:`, error.message);
// Send error to client
if (ws.readyState === 1) {
ws.send(Buffer.from(`ERROR: Connection to MUD server failed: ${error.message}\r\n`));
setTimeout(() => {
if (ws.readyState === 1) ws.close();
}, 1000);
}
// Remove from connections map
connections.delete(connectionId);
});
// Send session ID to client in proper JSON format
ws.send(`[SYSTEM]${JSON.stringify({ sessionId: currentSessionId })}`);
} catch (error) {
console.error(`Error creating socket connection: ${error.message}`);
if (ws.readyState === 1) {
ws.send(Buffer.from(`ERROR: Failed to connect to MUD server: ${error.message}\r\n`));
ws.close();
}
return;
}
function numberFromEnv(name, fallback, minimum, maximum) {
const parsed = Number.parseInt(process.env[name] || '', 10);
return Number.isFinite(parsed) && parsed >= minimum && parsed <= maximum ? parsed : fallback;
}
function createDeniedAddressList() {
const list = new BlockList();
for (const [address, prefix] of [
['0.0.0.0', 8], ['10.0.0.0', 8], ['100.64.0.0', 10], ['127.0.0.0', 8],
['169.254.0.0', 16], ['172.16.0.0', 12], ['192.0.0.0', 24], ['192.0.2.0', 24],
['192.168.0.0', 16], ['198.18.0.0', 15], ['198.51.100.0', 24], ['203.0.113.0', 24],
['224.0.0.0', 4], ['240.0.0.0', 4]
]) list.addSubnet(address, prefix, 'ipv4');
for (const [address, prefix] of [
['::', 128], ['::1', 128], ['64:ff9b::', 96], ['2001::', 32],
['2001:db8::', 32], ['2002::', 16], ['fc00::', 7], ['fe80::', 10], ['ff00::', 8]
]) list.addSubnet(address, prefix, 'ipv6');
return list;
}
function getClientIp(request) {
if (process.env.TRUST_PROXY === '1') {
const forwarded = request.headers['x-forwarded-for'];
if (typeof forwarded === 'string' && forwarded.length > 0) return forwarded.split(',')[0].trim();
}
return request.socket.remoteAddress || 'unknown';
}
// Store the connection with its settings
connections.set(connectionId, {
ws,
socket,
sessionId: currentSessionId,
settings: connectionSettings
function sendControl(ws, payload) {
if (ws.readyState === WebSocket.OPEN) ws.send(JSON.stringify(payload));
}
function failUpgrade(socket, status, message) {
socket.write(`HTTP/1.1 ${status}\r\nConnection: close\r\nContent-Type: text/plain\r\n\r\n${message}`);
socket.destroy();
}
function countSessionsForIp(clientIp) {
let count = 0;
for (const session of sessions.values()) if (session.clientIp === clientIp) count += 1;
return count;
}
function recordConnectionAttempt(clientIp) {
const cutoff = Date.now() - 10 * 60_000;
const recent = (connectionAttempts.get(clientIp) || []).filter((timestamp) => timestamp > cutoff);
if (recent.length >= NEW_CONNECTION_LIMIT) return false;
recent.push(Date.now());
connectionAttempts.set(clientIp, recent);
return true;
}
function validateConnectMessage(value) {
if (!value || typeof value !== 'object' || value.type !== 'connect') throw new Error('The first frame must be a connect control message.');
if (typeof value.host !== 'string' || value.host.length < 1 || value.host.length > 253) throw new Error('Invalid host.');
if (!/^[a-zA-Z0-9._:-]+$/.test(value.host)) throw new Error('Invalid host characters.');
if (!Number.isInteger(value.port) || value.port < 1 || value.port > 65535 || DENIED_PORTS.has(value.port)) throw new Error('Invalid or denied port.');
if (typeof value.tls !== 'boolean') throw new Error('Invalid TLS setting.');
if (value.resumeToken !== undefined && (typeof value.resumeToken !== 'string' || value.resumeToken.length > 128)) throw new Error('Invalid resume token.');
return { host: value.host, port: value.port, useTls: value.tls, resumeToken: value.resumeToken };
}
async function resolvePublicTarget(host) {
const directFamily = net.isIP(host);
const answers = directFamily ? [{ address: host, family: directFamily }] : await lookup(host, { all: true, verbatim: true });
if (answers.length === 0) throw new Error('Host did not resolve.');
for (const answer of answers) {
if (isDeniedAddress(answer.address, answer.family)) throw new Error('Target resolves to a non-public address.');
}
return answers[0];
}
function isDeniedAddress(address, family = net.isIP(address)) {
const mapped = address.match(/^::ffff:(?:(\d+\.\d+\.\d+\.\d+)|([0-9a-f]+):([0-9a-f]+))$/i);
if (mapped) {
let ipv4 = mapped[1];
if (!ipv4) {
const high = Number.parseInt(mapped[2], 16);
const low = Number.parseInt(mapped[3], 16);
ipv4 = `${high >> 8}.${high & 255}.${low >> 8}.${low & 255}`;
}
return deniedAddresses.check(ipv4, 'ipv4');
}
return deniedAddresses.check(address, family === 4 ? 'ipv4' : 'ipv6');
}
function consumeTraffic(session, direction, bytes) {
if (Date.now() - session.traffic.startedAt >= 1_000) session.traffic = { startedAt: Date.now(), inbound: 0, outbound: 0 };
session.traffic[direction] += bytes;
return session.traffic[direction] <= MAX_BYTES_PER_SECOND;
}
function bufferMessage(session, data) {
session.buffer.push(Buffer.from(data));
session.bufferBytes += data.length;
while (session.buffer.length > MAX_BUFFER_MESSAGES || session.bufferBytes > MAX_BUFFER_BYTES) {
const removed = session.buffer.shift();
if (removed) session.bufferBytes -= removed.length;
}
}
function destroySession(session, reason = 'closed') {
if (session.closed) return;
session.closed = true;
if (session.persistenceTimer) clearTimeout(session.persistenceTimer);
sessions.delete(session.token);
const attached = session.ws;
session.ws = null;
if (attached) sendControl(attached, { type: 'upstream_closed', reason });
if (!session.socket.destroyed) session.socket.destroy();
}
function rotateSessionToken(session) {
sessions.delete(session.token);
session.token = randomBytes(32).toString('base64url');
sessions.set(session.token, session);
}
function attachWebSocket(session, ws, resumed) {
if (session.persistenceTimer) clearTimeout(session.persistenceTimer);
session.persistenceTimer = null;
session.ws = ws;
rotateSessionToken(session);
if (resumed) {
sendControl(ws, { type: 'replay_started', messageCount: session.buffer.length });
for (const message of session.buffer) if (ws.readyState === WebSocket.OPEN) ws.send(message);
const messagesReplayed = session.buffer.length;
session.buffer = [];
session.bufferBytes = 0;
sendControl(ws, { type: 'replay_finished', messagesReplayed });
}
sendControl(ws, { type: resumed ? 'session_resumed' : 'session_started', resumeToken: session.token });
}
async function createSession(ws, request, target) {
const clientIp = getClientIp(request);
const origin = request.headers.origin || '';
if (sessions.size >= MAX_GLOBAL_SESSIONS) throw new Error('Proxy capacity reached.');
if (countSessionsForIp(clientIp) >= MAX_SESSIONS_PER_IP) throw new Error('Per-client connection limit reached.');
if (!recordConnectionAttempt(clientIp)) throw new Error('Connection rate limit reached.');
const resolved = await resolvePublicTarget(target.host);
const socketOptions = { host: resolved.address, port: target.port, family: resolved.family,
...(target.useTls ? { servername: net.isIP(target.host) ? undefined : target.host, rejectUnauthorized: true } : {}) };
const socket = target.useTls ? tls.connect(socketOptions) : net.createConnection(socketOptions);
const session = { token: randomBytes(32).toString('base64url'), clientIp, origin, target, socket, ws: null,
buffer: [], bufferBytes: 0, persistenceTimer: null, closed: false,
traffic: { startedAt: Date.now(), inbound: 0, outbound: 0 } };
sessions.set(session.token, session);
const connected = new Promise((resolve, reject) => {
const connectedEvent = target.useTls ? 'secureConnect' : 'connect';
const fail = (error) => reject(error instanceof Error ? error : new Error('Upstream connection failed.'));
socket.once(connectedEvent, resolve);
socket.once('error', fail);
socket.once('close', () => fail(new Error('Upstream closed before connecting.')));
socket.setTimeout(CONNECT_TIMEOUT_MS, () => {
fail(new Error('Upstream connection timed out.'));
destroySession(session, 'timeout');
});
});
// Handle data from the MUD server - only in regular mode, not test mode
if (socket) {
socket.on('data', (data) => {
// Check for GMCP data (IAC SB GMCP) - very basic check for debugging
// IAC = 255, SB = 250, GMCP = 201
let isGmcp = false;
for (let i = 0; i < data.length - 2; i++) {
if (data[i] === 255 && data[i+1] === 250 && data[i+2] === 201) {
isGmcp = true;
console.log('WebSocket server: Detected GMCP data in server response');
break;
}
}
// Forward data to the WebSocket client if it's still open
if (ws.readyState === 1) { // WebSocket.OPEN
ws.send(data);
console.log(`WebSocket server: Sent ${data.length} bytes to client${isGmcp ? ' (contains GMCP data)' : ''}`);
} else {
// WebSocket is not open, buffer the message if we have a session
if (currentSessionId) {
bufferMessage(currentSessionId, data);
}
}
});
socket.on('data', (data) => {
if (!consumeTraffic(session, 'inbound', data.length)) return destroySession(session, 'traffic_limit');
if (session.ws?.readyState === WebSocket.OPEN) session.ws.send(data);
else bufferMessage(session, data);
});
socket.on('error', (error) => { if (session.ws) sendControl(session.ws, { type: 'error', code: 'UPSTREAM_ERROR', message: error.message }); });
socket.on('close', () => destroySession(session, 'upstream_closed'));
socket.on('drain', () => session.ws?.resume());
try {
await connected;
} catch (error) {
destroySession(session, 'connect_failed');
throw error;
}
// Handle socket close from MUD server - this should trigger cleanup
if (socket) {
socket.on('close', () => {
console.log(`MUD connection closed by server for ${mudHost}:${mudPort}`);
// Close WebSocket if it's still open
if (ws.readyState === 1) {
ws.close();
}
// Remove from connections map
connections.delete(connectionId);
// Also cleanup any persistent connection
if (currentSessionId) {
cleanupPersistentConnection(currentSessionId);
}
});
socket.setTimeout(0);
if (ws.readyState !== WebSocket.OPEN) {
destroySession(session, 'client_closed_during_connect');
throw new Error('Client closed while the upstream connection was opening.');
}
attachWebSocket(session, ws, false);
return session;
}
// Handle WebSocket messages (data from client to server)
ws.on('message', (message) => {
function tryResume(ws, request, target) {
if (!target.resumeToken) return null;
const session = sessions.get(target.resumeToken);
const clientIp = getClientIp(request);
const origin = request.headers.origin || '';
if (!session || session.ws || session.clientIp !== clientIp || session.origin !== origin || session.target.host !== target.host ||
session.target.port !== target.port || session.target.useTls !== target.useTls) return null;
attachWebSocket(session, ws, true);
return session;
}
wss.on('connection', (ws, request) => {
let session = null;
let explicitDisconnect = false;
let initialized = false;
const initializationTimer = setTimeout(() => { if (!initialized) ws.close(1008, 'Connect control timeout'); }, 5_000);
ws.on('message', async (data, isBinary) => {
try {
// Skip if this is a test connection (already handled in the test mode section)
const conn = connections.get(connectionId);
if (conn && conn.testMode) return;
// Check for system messages
const messageStr = message.toString();
if (messageStr.startsWith('[SYSTEM]')) {
try {
const jsonStr = messageStr.substring(8); // Remove "[SYSTEM]"
const systemData = JSON.parse(jsonStr);
if (systemData.type === 'explicit_disconnect') {
console.log(`Received explicit disconnect command for session ${currentSessionId}`);
// This is an explicit disconnect - don't persist the connection
if (socket && socket.writable) {
socket.end();
}
if (ws.readyState === 1) {
ws.close();
}
connections.delete(connectionId);
if (currentSessionId) {
cleanupPersistentConnection(currentSessionId);
}
return;
}
} catch (error) {
console.error('Error parsing system message:', error);
}
// Don't forward system messages to the MUD server
if (!initialized) {
if (isBinary || data.length > MAX_CONTROL_BYTES) throw new Error('Invalid connect control frame.');
const target = validateConnectMessage(JSON.parse(data.toString('utf8')));
initialized = true;
clearTimeout(initializationTimer);
session = tryResume(ws, request, target) || await createSession(ws, request, target);
return;
}
// Legacy support for old disconnect command
if (messageStr.trim() === '[DISCONNECT]') {
console.log(`Received legacy disconnect command for session ${currentSessionId}`);
// This is an explicit disconnect - don't persist the connection
if (socket && socket.writable) {
socket.end();
}
if (ws.readyState === 1) {
ws.close();
}
connections.delete(connectionId);
if (currentSessionId) {
cleanupPersistentConnection(currentSessionId);
}
return;
}
// Check for GMCP data (IAC SB GMCP) in client messages
let isGmcp = false;
if (message instanceof Buffer || message instanceof Uint8Array) {
for (let i = 0; i < message.length - 2; i++) {
if (message[i] === 255 && message[i+1] === 250 && message[i+2] === 201) {
isGmcp = true;
console.log('WebSocket server: Detected GMCP data in client message');
break;
}
}
}
// Forward data to the MUD server
// The message might be Buffer, ArrayBuffer, or string
if (conn && conn.socket && conn.socket.writable) {
conn.socket.write(message);
console.log(`WebSocket server: Sent ${message.length} bytes to MUD server${isGmcp ? ' (contains GMCP data)' : ''}`);
} else {
console.error('Socket not writable, cannot send data to MUD server');
if (ws.readyState === 1) { // WebSocket.OPEN
ws.send(Buffer.from(`ERROR: Cannot send data to MUD server: Socket not connected\r\n`));
if (!isBinary) {
if (data.length > MAX_CONTROL_BYTES) throw new Error('Control frame too large.');
const control = JSON.parse(data.toString('utf8'));
if (control.type === 'disconnect') {
explicitDisconnect = true;
if (session) destroySession(session, 'client_disconnect');
ws.close(1000, 'Disconnected');
return;
}
throw new Error('Unknown control frame.');
}
if (!session || session.ws !== ws || !session.socket.writable) throw new Error('Upstream connection is not writable.');
if (!consumeTraffic(session, 'outbound', data.length)) return destroySession(session, 'traffic_limit');
if (!session.socket.write(data)) ws.pause();
} catch (error) {
console.error('Error forwarding message to MUD server:', error);
if (ws.readyState === 1) { // WebSocket.OPEN
const errorMessage = error instanceof Error ? error.message : String(error);
ws.send(Buffer.from(`ERROR: Failed to send data to MUD server: ${errorMessage}\r\n`));
}
sendControl(ws, { type: 'error', code: initialized ? 'PROTOCOL_ERROR' : 'CONNECT_ERROR', message: error instanceof Error ? error.message : 'Unknown proxy error.' });
if (!session) ws.close(1008, 'Connection rejected');
}
});
// Handle WebSocket close - THIS IS THE KEY CHANGE FOR PERSISTENCE
ws.on('close', () => {
console.log(`WebSocket closed for ${mudHost}:${mudPort} (session: ${currentSessionId})`);
const conn = connections.get(connectionId);
if (conn && !conn.testMode && conn.socket && !conn.socket.destroyed) {
console.log(`Moving connection to persistent state for ${conn.settings.persistenceTimeoutMs / 1000} seconds`);
// Move the connection to persistent storage instead of closing it
// Use this connection's specific timeout setting
const timeoutId = setTimeout(() => {
console.log(`Session ${currentSessionId} timed out, closing MUD connection`);
cleanupPersistentConnection(currentSessionId);
}, conn.settings.persistenceTimeoutMs);
persistentConnections.set(currentSessionId, {
socket: conn.socket,
mudHost,
mudPort,
useSSL,
timeoutId,
lastActivity: Date.now(),
messageBuffer: [],
bufferSize: 0,
settings: conn.settings // Store the connection's settings
});
console.log(`Session ${currentSessionId} will persist for ${conn.settings.persistenceTimeoutMs / 1000} seconds with settings: ${conn.settings.maxBufferMessages} msgs/${conn.settings.maxBufferSizeKB}KB`);
} else if (conn && conn.socket) {
// Fallback to immediate cleanup if needed
conn.socket.end();
}
// Remove from active connections map
connections.delete(connectionId);
});
// Handle WebSocket errors
ws.on('error', (error) => {
console.error(`WebSocket error for ${mudHost}:${mudPort}:`, error.message);
// Close socket on error - but only if it's not going to be persisted
const conn = connections.get(connectionId);
if (conn && conn.socket) {
conn.socket.end();
}
// Remove from connections map
connections.delete(connectionId);
clearTimeout(initializationTimer);
if (!session || explicitDisconnect || session.ws !== ws) return;
session.ws = null;
session.persistenceTimer = setTimeout(() => destroySession(session, 'resume_timeout'), PERSISTENCE_TIMEOUT_MS);
});
ws.on('error', () => ws.close());
});
// Handle HTTP server upgrade (WebSocket handshake)
server.on('upgrade', (request, socket, head) => {
// Parse URL to get query parameters
const { pathname, query } = parse(request.url || '', true);
// Only handle WebSocket connections to /mud-ws
if (pathname === '/mud-ws') {
// Extract MUD server details from query parameters
const { host, port, useSSL } = query;
if (!host || !port) {
socket.write('HTTP/1.1 400 Bad Request\r\n\r\n');
socket.destroy();
return;
}
// Handle WebSocket upgrade
wss.handleUpgrade(request, socket, head, (ws) => {
wss.emit('connection', ws, request, host, port, useSSL === 'true');
});
} else {
// For other upgrades (not to /mud-ws), close the connection
socket.destroy();
}
let pathname;
try { pathname = new URL(request.url || '/', 'http://localhost').pathname; } catch { return failUpgrade(socket, '400 Bad Request', 'Invalid URL'); }
if (pathname !== '/mud-ws') return failUpgrade(socket, '404 Not Found', 'Not found');
const origin = request.headers.origin;
if (typeof origin !== 'string' || !allowedOrigins.has(origin)) return failUpgrade(socket, '403 Forbidden', 'Origin not allowed');
wss.handleUpgrade(request, socket, head, (client) => wss.emit('connection', client, request));
});
// Periodic cleanup of abandoned persistent connections
setInterval(() => {
const now = Date.now();
for (const [sessionId, persistentConn] of persistentConnections.entries()) {
// Clean up connections that have been inactive for too long
// Use double the connection's specific timeout or default
const timeoutThreshold = (persistentConn.settings?.persistenceTimeoutMs || DEFAULT_PERSISTENCE_TIMEOUT) * 2;
if (now - persistentConn.lastActivity > timeoutThreshold) {
console.log(`Cleaning up abandoned session: ${sessionId}`);
cleanupPersistentConnection(sessionId);
}
}
}, DEFAULT_PERSISTENCE_TIMEOUT); // Run cleanup every default timeout period
// Start the WebSocket server
const PORT = process.env.WS_PORT || 3001;
server.listen(PORT, () => {
console.log(`WebSocket server is running on port ${PORT}`);
console.log(`Default connection persistence timeout: ${DEFAULT_PERSISTENCE_TIMEOUT / 1000} seconds (configurable per connection)`);
});
export default server;
function shutdown() {
wss.close();
for (const session of [...sessions.values()]) destroySession(session, 'server_shutdown');
server.close(() => process.exit(0));
setTimeout(() => process.exit(1), 5_000).unref();
}
process.on('SIGINT', shutdown);
process.on('SIGTERM', shutdown);
if (process.env.NODE_ENV !== 'test') server.listen(PORT, () => console.log(`MUD WebSocket proxy listening on port ${PORT}`));
export { server, validateConnectMessage, resolvePublicTarget, isDeniedAddress };