Files
smartproxy/ts/proxies/smart-proxy/utils/socket-handlers.ts

311 lines
9.0 KiB
TypeScript

/**
* Socket Handler Functions
*
* This module provides pre-built socket handlers for common use cases
* like echoing, proxying, HTTP responses, and redirects.
*/
import * as plugins from '../../../plugins.js';
import type { IRouteContext } from '../models/route-types.js';
import { createSocketTracker } from '../../../core/utils/socket-tracker.js';
/**
* Minimal HTTP request parser for socket handlers.
* Parses method, path, and optionally headers from a raw buffer.
*/
function parseHttpRequest(data: Buffer, extractHeaders: boolean = false): {
method: string;
path: string;
headers: Record<string, string>;
isComplete: boolean;
body?: string;
} | null {
const str = data.toString('utf8');
const headerEnd = str.indexOf('\r\n\r\n');
const isComplete = headerEnd !== -1;
const headerSection = isComplete ? str.slice(0, headerEnd) : str;
const lines = headerSection.split('\r\n');
const requestLine = lines[0];
if (!requestLine) return null;
const parts = requestLine.split(' ');
if (parts.length < 2) return null;
const method = parts[0];
const path = parts[1];
// Quick check: valid HTTP method
const validMethods = ['GET', 'POST', 'PUT', 'DELETE', 'PATCH', 'HEAD', 'OPTIONS', 'CONNECT', 'TRACE'];
if (!validMethods.includes(method)) return null;
const headers: Record<string, string> = {};
if (extractHeaders) {
for (let i = 1; i < lines.length; i++) {
const colonIdx = lines[i].indexOf(':');
if (colonIdx > 0) {
const name = lines[i].slice(0, colonIdx).trim().toLowerCase();
const value = lines[i].slice(colonIdx + 1).trim();
headers[name] = value;
}
}
}
const body = isComplete ? str.slice(headerEnd + 4) : undefined;
return { method, path, headers, isComplete, body };
}
/**
* Pre-built socket handlers for common use cases
*/
export const SocketHandlers = {
/**
* Simple echo server handler
*/
echo: (socket: plugins.net.Socket, context: IRouteContext) => {
socket.write('ECHO SERVER READY\n');
socket.on('data', data => socket.write(data));
},
/**
* TCP proxy handler
*/
proxy: (targetHost: string, targetPort: number) => (socket: plugins.net.Socket, context: IRouteContext) => {
const target = plugins.net.connect(targetPort, targetHost);
socket.pipe(target);
target.pipe(socket);
socket.on('close', () => target.destroy());
target.on('close', () => socket.destroy());
target.on('error', (err) => {
console.error('Proxy target error:', err);
socket.destroy();
});
},
/**
* Line-based protocol handler
*/
lineProtocol: (handler: (line: string, socket: plugins.net.Socket) => void) => (socket: plugins.net.Socket, context: IRouteContext) => {
let buffer = '';
socket.on('data', (data) => {
buffer += data.toString();
const lines = buffer.split('\n');
buffer = lines.pop() || '';
lines.forEach(line => {
if (line.trim()) {
handler(line.trim(), socket);
}
});
});
},
/**
* Simple HTTP response handler (for testing)
*/
httpResponse: (statusCode: number, body: string) => (socket: plugins.net.Socket, context: IRouteContext) => {
const response = [
`HTTP/1.1 ${statusCode} ${statusCode === 200 ? 'OK' : 'Error'}`,
'Content-Type: text/plain',
`Content-Length: ${body.length}`,
'Connection: close',
'',
body
].join('\r\n');
socket.write(response);
socket.end();
},
/**
* Block connection immediately
*/
block: (message?: string) => (socket: plugins.net.Socket, context: IRouteContext) => {
const finalMessage = message || `Connection blocked from ${context.clientIp}`;
if (finalMessage) {
socket.write(finalMessage);
}
socket.end();
},
/**
* HTTP block response
*/
httpBlock: (statusCode: number = 403, message?: string) => (socket: plugins.net.Socket, context: IRouteContext) => {
const defaultMessage = `Access forbidden for ${context.domain || context.clientIp}`;
const finalMessage = message || defaultMessage;
const response = [
`HTTP/1.1 ${statusCode} ${finalMessage}`,
'Content-Type: text/plain',
`Content-Length: ${finalMessage.length}`,
'Connection: close',
'',
finalMessage
].join('\r\n');
socket.write(response);
socket.end();
},
/**
* HTTP redirect handler
*/
httpRedirect: (locationTemplate: string, statusCode: number = 301) => (socket: plugins.net.Socket, context: IRouteContext) => {
const tracker = createSocketTracker(socket);
const handleData = (data: Buffer) => {
const parsed = parseHttpRequest(data);
if (parsed) {
const path = parsed.path || '/';
const domain = context.domain || 'localhost';
const port = context.port;
const finalLocation = locationTemplate
.replace('{domain}', domain)
.replace('{port}', String(port))
.replace('{path}', path)
.replace('{clientIp}', context.clientIp);
const message = `Redirecting to ${finalLocation}`;
const response = [
`HTTP/1.1 ${statusCode} ${statusCode === 301 ? 'Moved Permanently' : 'Found'}`,
`Location: ${finalLocation}`,
'Content-Type: text/plain',
`Content-Length: ${message.length}`,
'Connection: close',
'',
message
].join('\r\n');
socket.write(response);
} else {
socket.write('HTTP/1.1 400 Bad Request\r\nConnection: close\r\n\r\n');
}
socket.end();
tracker.cleanup();
};
socket.once('data', handleData);
tracker.addListener('error', (err) => {
tracker.safeDestroy(err);
});
tracker.addListener('close', () => {
tracker.cleanup();
});
},
/**
* HTTP server handler for ACME challenges and other HTTP needs
*/
httpServer: (handler: (req: { method: string; url: string; headers: Record<string, string>; body?: string }, res: { status: (code: number) => void; header: (name: string, value: string) => void; send: (data: string) => void; end: () => void }) => void) => (socket: plugins.net.Socket, context: IRouteContext) => {
const tracker = createSocketTracker(socket);
let requestParsed = false;
let responseTimer: NodeJS.Timeout | null = null;
const processData = (data: Buffer) => {
if (requestParsed) return;
const parsed = parseHttpRequest(data, true);
if (!parsed || !parsed.isComplete) {
return; // Not a complete HTTP request yet
}
requestParsed = true;
socket.removeListener('data', processData);
const req = {
method: parsed.method,
url: parsed.path,
headers: parsed.headers,
body: parsed.body || ''
};
let statusCode = 200;
const responseHeaders: Record<string, string> = {};
let ended = false;
const res = {
status: (code: number) => {
statusCode = code;
},
header: (name: string, value: string) => {
responseHeaders[name] = value;
},
send: (data: string) => {
if (ended) return;
ended = true;
if (responseTimer) {
clearTimeout(responseTimer);
responseTimer = null;
}
if (!responseHeaders['content-type']) {
responseHeaders['content-type'] = 'text/plain';
}
responseHeaders['content-length'] = String(data.length);
responseHeaders['connection'] = 'close';
const statusText = statusCode === 200 ? 'OK' :
statusCode === 404 ? 'Not Found' :
statusCode === 500 ? 'Internal Server Error' : 'Response';
let response = `HTTP/1.1 ${statusCode} ${statusText}\r\n`;
for (const [name, value] of Object.entries(responseHeaders)) {
response += `${name}: ${value}\r\n`;
}
response += '\r\n';
response += data;
socket.write(response);
socket.end();
},
end: () => {
if (ended) return;
ended = true;
socket.write('HTTP/1.1 200 OK\r\nContent-Length: 0\r\nConnection: close\r\n\r\n');
socket.end();
}
};
try {
handler(req, res);
responseTimer = setTimeout(() => {
if (!ended) {
res.send('');
}
responseTimer = null;
}, 1000);
tracker.addTimer(responseTimer);
} catch (error) {
if (!ended) {
res.status(500);
res.send('Internal Server Error');
}
tracker.safeDestroy(error instanceof Error ? error : new Error('Handler error'));
}
};
tracker.addListener('data', processData);
tracker.addListener('error', (err) => {
if (!requestParsed) {
tracker.safeDestroy(err);
}
});
tracker.addListener('close', () => {
if (responseTimer) {
clearTimeout(responseTimer);
responseTimer = null;
}
tracker.cleanup();
});
}
};