Use V2rayN (V2ray Client) to Protect Your Online Privacy & Bypass Internet Censorship – 51 Security

// <!–GAMFC–>version base on commit 5a112a0a0994b8bb834427ac84133501407f6413, time is 2024-10-11 04:49:19 UTC<!–GAMFC-END–>.
// @ts-ignore
import { connect } from ‘cloudflare:sockets’;
// How to generate your own UUID:
// [Windows] Press “Win + R”, input cmd and run:  Powershell -NoExit -Command “https://www.51sec.org/?p=5022::NewGuid()”
let userID = ‘d342d11e-d424-4583-b36e-524ab1f0afa4’;
let proxyIP = ”;

if (!isValidUUID(userID)) {
throw new Error(‘uuid is not valid’);
}
export default {
/**
* @param {import(“@cloudflare/workers-types”).Request} request
* @param {{UUID: string, PROXYIP: string}} env
* @param {import(“@cloudflare/workers-types”).ExecutionContext} ctx
* @returns {Promise<Response>}
*/
async fetch(request, env, ctx) {
try {
userID = env.UUID || userID;
proxyIP = env.PROXYIP || proxyIP;
const upgradeHeader = request.headers.get(‘Upgrade’);
if (!upgradeHeader || upgradeHeader !== ‘websocket’) {
const url = new URL(request.url);
switch (url.pathname) {
case ‘/’:
return new Response(JSON.stringify(request.cf), { status: 200 });
case `/${userID}`: {
const vlessConfig = getVLESSConfig(userID, request.headers.get(‘Host’));
return new Response(`${vlessConfig}`, {
status: 200,
headers: {
“Content-Type”: “text/plain;charset=utf-8”,
}
});
}
default:
return new Response(‘Not found’, { status: 404 });
}
} else {
return await vlessOverWSHandler(request);
}
} catch (err) {
/** @type {Error} */ let e = err;
return new Response(e.toString());
}
},
};



/**
 * 
 * @param {import(“@cloudflare/workers-types”).Request} request
 */
async function vlessOverWSHandler(request) {
/** @type {import(“@cloudflare/workers-types”).WebSocket[]} */
// @ts-ignore
const webSocketPair = new WebSocketPair();
const [client, webSocket] = Object.values(webSocketPair);
webSocket.accept();
let address = ”;
let portWithRandomLog = ”;
const log = (/** @type {string} */ info, /** @type {string | undefined} */ event) => {
console.log(`[${address}:${portWithRandomLog}] ${info}`, event || ”);
};
const earlyDataHeader = request.headers.get(‘sec-websocket-protocol’) || ”;
const readableWebSocketStream = makeReadableWebSocketStream(webSocket, earlyDataHeader, log);
/** @type {{ value: import(“@cloudflare/workers-types”).Socket | null}}*/
let remoteSocketWapper = {
value: null,
};
let udpStreamWrite = null;
let isDns = false;
// ws –> remote
readableWebSocketStream.pipeTo(new WritableStream({
async write(chunk, controller) {
if (isDns && udpStreamWrite) {
return udpStreamWrite(chunk);
}
if (remoteSocketWapper.value) {
const writer = remoteSocketWapper.value.writable.getWriter()
await writer.write(chunk);
writer.releaseLock();
return;
}
const {
hasError,
message,
portRemote = 443,
addressRemote = ”,
rawDataIndex,
vlessVersion = new Uint8Array([0, 0]),
isUDP,
} = processVlessHeader(chunk, userID);
address = addressRemote;
portWithRandomLog = `${portRemote}–${Math.random()} ${isUDP ? ‘udp ‘ : ‘tcp ‘
} `;
if (hasError) {
// controller.error(message);
throw new Error(message); // cf seems has bug, controller.error will not end stream
// webSocket.close(1000, message);
return;
}
// if UDP but port not DNS port, close it
if (isUDP) {
if (portRemote === 53) {
isDns = true;
} else {
// controller.error(‘UDP proxy only enable for DNS which is port 53’);
throw new Error(‘UDP proxy only enable for DNS which is port 53’); // cf seems has bug, controller.error will not end stream
return;
}
}
// [“version”, “附加信息长度 N”]
const vlessResponseHeader = new Uint8Array([vlessVersion[0], 0]);
const rawClientData = chunk.slice(rawDataIndex);
// TODO: support udp here when cf runtime has udp support
if (isDns) {
const { write } = await handleUDPOutBound(webSocket, vlessResponseHeader, log);
udpStreamWrite = write;
udpStreamWrite(rawClientData);
return;
}
handleTCPOutBound(remoteSocketWapper, addressRemote, portRemote, rawClientData, webSocket, vlessResponseHeader, log);
},
close() {
log(`readableWebSocketStream is close`);
},
abort(reason) {
log(`readableWebSocketStream is abort`, JSON.stringify(reason));
},
})).catch((err) => {
log(‘readableWebSocketStream pipeTo error’, err);
});
return new Response(null, {
status: 101,
// @ts-ignore
webSocket: client,
});
}
/**
 * Handles outbound TCP connections.
 *
 * @param {any} remoteSocket 
 * @param {string} addressRemote The remote address to connect to.
 * @param {number} portRemote The remote port to connect to.
 * @param {Uint8Array} rawClientData The raw client data to write.
 * @param {import(“@cloudflare/workers-types”).WebSocket} webSocket The WebSocket to pass the remote socket to.
 * @param {Uint8Array} vlessResponseHeader The VLESS response header.
 * @param {function} log The logging function.
 * @returns {Promise<void>} The remote socket.
 */
async function handleTCPOutBound(remoteSocket, addressRemote, portRemote, rawClientData, webSocket, vlessResponseHeader, log,) {
async function connectAndWrite(address, port) {
/** @type {import(“@cloudflare/workers-types”).Socket} */
const tcpSocket = connect({
hostname: address,
port: port,
});
remoteSocket.value = tcpSocket;
log(`connected to ${address}:${port}`);
const writer = tcpSocket.writable.getWriter();
await writer.write(rawClientData); // first write, nomal is tls client hello
writer.releaseLock();
return tcpSocket;
}
// if the cf connect tcp socket have no incoming data, we retry to redirect ip
async function retry() {
const tcpSocket = await connectAndWrite(proxyIP || addressRemote, portRemote)
// no matter retry success or not, close websocket
tcpSocket.closed.catch(error => {
console.log(‘retry tcpSocket closed error’, error);
}).finally(() => {
safeCloseWebSocket(webSocket);
})
remoteSocketToWS(tcpSocket, webSocket, vlessResponseHeader, null, log);
}
const tcpSocket = await connectAndWrite(addressRemote, portRemote);
// when remoteSocket is ready, pass to websocket
// remote–> ws
remoteSocketToWS(tcpSocket, webSocket, vlessResponseHeader, retry, log);
}
/**
 * 
 * @param {import(“@cloudflare/workers-types”).WebSocket} webSocketServer
 * @param {string} earlyDataHeader for ws 0rtt
 * @param {(info: string)=> void} log for ws 0rtt
 */
function makeReadableWebSocketStream(webSocketServer, earlyDataHeader, log) {
let readableStreamCancel = false;
const stream = new ReadableStream({
start(controller) {
webSocketServer.addEventListener(‘message’, (event) => {
if (readableStreamCancel) {
return;
}
const message = event.data;
controller.enqueue(message);
});
// The event means that the client closed the client -> server stream.
// However, the server -> client stream is still open until you call close() on the server side.
// The WebSocket protocol says that a separate close message must be sent in each direction to fully close the socket.
webSocketServer.addEventListener(‘close’, () => {
// client send close, need close server
// if stream is cancel, skip controller.close
safeCloseWebSocket(webSocketServer);
if (readableStreamCancel) {
return;
}
controller.close();
}
);
webSocketServer.addEventListener(‘error’, (err) => {
log(‘webSocketServer has error’);
controller.error(err);
}
);
// for ws 0rtt
const { earlyData, error } = base64ToArrayBuffer(earlyDataHeader);
if (error) {
controller.error(error);
} else if (earlyData) {
controller.enqueue(earlyData);
}
},
pull(controller) {
// if ws can stop read if stream is full, we can implement backpressure
// https://streams.spec.whatwg.org/#example-rs-push-backpressure
},
cancel(reason) {
// 1. pipe WritableStream has error, this cancel will called, so ws handle server close into here
// 2. if readableStream is cancel, all controller.close/enqueue need skip,
// 3. but from testing controller.error still work even if readableStream is cancel
if (readableStreamCancel) {
return;
}
log(`ReadableStream was canceled, due to ${reason}`)
readableStreamCancel = true;
safeCloseWebSocket(webSocketServer);
}
});
return stream;
}
// https://xtls.github.io/development/protocols/vless.html
// https://github.com/zizifn/excalidraw-backup/blob/main/v2ray-protocol.excalidraw
/**
 * 
 * @param { ArrayBuffer} vlessBuffer 
 * @param {string} userID 
 * @returns 
 */
function processVlessHeader(
vlessBuffer,
userID
) {
if (vlessBuffer.byteLength < 24) {
return {
hasError: true,
message: ‘invalid data’,
};
}
const version = new Uint8Array(vlessBuffer.slice(0, 1));
let isValidUser = false;
let isUDP = false;
if (stringify(new Uint8Array(vlessBuffer.slice(1, 17))) === userID) {
isValidUser = true;
}
if (!isValidUser) {
return {
hasError: true,
message: ‘invalid user’,
};
}
const optLength = new Uint8Array(vlessBuffer.slice(17, 18))[0];
//skip opt for now
const command = new Uint8Array(
vlessBuffer.slice(18 + optLength, 18 + optLength + 1)
)[0];
// 0x01 TCP
// 0x02 UDP
// 0x03 MUX
if (command === 1) {
} else if (command === 2) {
isUDP = true;
} else {
return {
hasError: true,
message: `command ${command} is not support, command 01-tcp,02-udp,03-mux`,
};
}
const portIndex = 18 + optLength + 1;
const portBuffer = vlessBuffer.slice(portIndex, portIndex + 2);
// port is big-Endian in raw data etc 80 == 0x005d
const portRemote = new DataView(portBuffer).getUint16(0);
let addressIndex = portIndex + 2;
const addressBuffer = new Uint8Array(
vlessBuffer.slice(addressIndex, addressIndex + 1)
);
// 1–> ipv4  addressLength =4
// 2–> domain name addressLength=addressBuffer[1]
// 3–> ipv6  addressLength =16
const addressType = addressBuffer[0];
let addressLength = 0;
let addressValueIndex = addressIndex + 1;
let addressValue = ”;
switch (addressType) {
case 1:
addressLength = 4;
addressValue = new Uint8Array(
vlessBuffer.slice(addressValueIndex, addressValueIndex + addressLength)
).join(‘.’);
break;
case 2:
addressLength = new Uint8Array(
vlessBuffer.slice(addressValueIndex, addressValueIndex + 1)
)[0];
addressValueIndex += 1;
addressValue = new TextDecoder().decode(
vlessBuffer.slice(addressValueIndex, addressValueIndex + addressLength)
);
break;
case 3:
addressLength = 16;
const dataView = new DataView(
vlessBuffer.slice(addressValueIndex, addressValueIndex + addressLength)
);
// 2001:0db8:85a3:0000:0000:8a2e:0370:7334
const ipv6 = [];
for (let i = 0; i < 8; i++) {
ipv6.push(dataView.getUint16(i * 2).toString(16));
}
addressValue = ipv6.join(‘:’);
// seems no need add [] for ipv6
break;
default:
return {
hasError: true,
message: `invild  addressType is ${addressType}`,
};
}
if (!addressValue) {
return {
hasError: true,
message: `addressValue is empty, addressType is ${addressType}`,
};
}
return {
hasError: false,
addressRemote: addressValue,
addressType,
portRemote,
rawDataIndex: addressValueIndex + addressLength,
vlessVersion: version,
isUDP,
};
}

/**
 * 
 * @param {import(“@cloudflare/workers-types”).Socket} remoteSocket 
 * @param {import(“@cloudflare/workers-types”).WebSocket} webSocket 
 * @param {ArrayBuffer} vlessResponseHeader 
 * @param {(() => Promise<void>) | null} retry
 * @param {*} log 
 */
async function remoteSocketToWS(remoteSocket, webSocket, vlessResponseHeader, retry, log) {
// remote–> ws
let remoteChunkCount = 0;
let chunks = [];
/** @type {ArrayBuffer | null} */
let vlessHeader = vlessResponseHeader;
let hasIncomingData = false; // check if remoteSocket has incoming data
await remoteSocket.readable
.pipeTo(
new WritableStream({
start() {
},
/**
* 
* @param {Uint8Array} chunk 
* @param {*} controller 
*/
async write(chunk, controller) {
hasIncomingData = true;
// remoteChunkCount++;
if (webSocket.readyState !== WS_READY_STATE_OPEN) {
controller.error(
‘webSocket.readyState is not open, maybe close’
);
}
if (vlessHeader) {
webSocket.send(await new Blob([vlessHeader, chunk]).arrayBuffer());
vlessHeader = null;
} else {
// seems no need rate limit this, CF seems fix this??..
// if (remoteChunkCount > 20000) {
// // cf one package is 4096 byte(4kb),  4096 * 20000 = 80M
// await delay(1);
// }
webSocket.send(chunk);
}
},
close() {
log(`remoteConnection!.readable is close with hasIncomingData is ${hasIncomingData}`);
// safeCloseWebSocket(webSocket); // no need server close websocket frist for some case will casue HTTP ERR_CONTENT_LENGTH_MISMATCH issue, client will send close event anyway.
},
abort(reason) {
console.error(`remoteConnection!.readable abort`, reason);
},
})
)
.catch((error) => {
console.error(
`remoteSocketToWS has exception `,
error.stack || error
);
safeCloseWebSocket(webSocket);
});
// seems is cf connect socket have error,
// 1. Socket.closed will have error
// 2. Socket.readable will be close without any data coming
if (hasIncomingData === false && retry) {
log(`retry`)
retry();
}
}
/**
 * 
 * @param {string} base64Str 
 * @returns 
 */
function base64ToArrayBuffer(base64Str) {
if (!base64Str) {
return { error: null };
}
try {
// go use modified Base64 for URL rfc4648 which js atob not support
base64Str = base64Str.replace(/-/g, ‘+’).replace(/_/g, ‘/’);
const decode = atob(base64Str);
const arryBuffer = Uint8Array.from(decode, (c) => c.charCodeAt(0));
return { earlyData: arryBuffer.buffer, error: null };
} catch (error) {
return { error };
}
}
/**
 * This is not real UUID validation
 * @param {string} uuid 
 */
function isValidUUID(uuid) {
const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-[4][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
return uuidRegex.test(uuid);
}
const WS_READY_STATE_OPEN = 1;
const WS_READY_STATE_CLOSING = 2;
/**
 * Normally, WebSocket will not has exceptions when close.
 * @param {import(“@cloudflare/workers-types”).WebSocket} socket
 */
function safeCloseWebSocket(socket) {
try {
if (socket.readyState === WS_READY_STATE_OPEN || socket.readyState === WS_READY_STATE_CLOSING) {
socket.close();
}
} catch (error) {
console.error(‘safeCloseWebSocket error’, error);
}
}
const byteToHex = [];
for (let i = 0; i < 256; ++i) {
byteToHex.push((i + 256).toString(16).slice(1));
}
function unsafeStringify(arr, offset = 0) {
return (byteToHex[arr[offset + 0]] + byteToHex[arr[offset + 1]] + byteToHex[arr[offset + 2]] + byteToHex[arr[offset + 3]] + “-” + byteToHex[arr[offset + 4]] + byteToHex[arr[offset + 5]] + “-” + byteToHex[arr[offset + 6]] + byteToHex[arr[offset + 7]] + “-” + byteToHex[arr[offset + 8]] + byteToHex[arr[offset + 9]] + “-” + byteToHex[arr[offset + 10]] + byteToHex[arr[offset + 11]] + byteToHex[arr[offset + 12]] + byteToHex[arr[offset + 13]] + byteToHex[arr[offset + 14]] + byteToHex[arr[offset + 15]]).toLowerCase();
}
function stringify(arr, offset = 0) {
const uuid = unsafeStringify(arr, offset);
if (!isValidUUID(uuid)) {
throw TypeError(“Stringified UUID is invalid”);
}
return uuid;
}

/**
 * 
 * @param {import(“@cloudflare/workers-types”).WebSocket} webSocket 
 * @param {ArrayBuffer} vlessResponseHeader 
 * @param {(string)=> void} log 
 */
async function handleUDPOutBound(webSocket, vlessResponseHeader, log) {
let isVlessHeaderSent = false;
const transformStream = new TransformStream({
start(controller) {
},
transform(chunk, controller) {
// udp message 2 byte is the the length of udp data
// TODO: this should have bug, beacsue maybe udp chunk can be in two websocket message
for (let index = 0; index < chunk.byteLength;) {
const lengthBuffer = chunk.slice(index, index + 2);
const udpPakcetLength = new DataView(lengthBuffer).getUint16(0);
const udpData = new Uint8Array(
chunk.slice(index + 2, index + 2 + udpPakcetLength)
);
index = index + 2 + udpPakcetLength;
controller.enqueue(udpData);
}
},
flush(controller) {
}
});
// only handle dns udp for now
transformStream.readable.pipeTo(new WritableStream({
async write(chunk) {
const resp = await fetch(‘https://1.1.1.1/dns-query’,
{
method: ‘POST’,
headers: {
‘content-type’: ‘application/dns-message’,
},
body: chunk,
})
const dnsQueryResult = await resp.arrayBuffer();
const udpSize = dnsQueryResult.byteLength;
// console.log([…new Uint8Array(dnsQueryResult)].map((x) => x.toString(16)));
const udpSizeBuffer = new Uint8Array([(udpSize >> 8) & 0xff, udpSize & 0xff]);
if (webSocket.readyState === WS_READY_STATE_OPEN) {
log(`doh success and dns message length is ${udpSize}`);
if (isVlessHeaderSent) {
webSocket.send(await new Blob([udpSizeBuffer, dnsQueryResult]).arrayBuffer());
} else {
webSocket.send(await new Blob([vlessResponseHeader, udpSizeBuffer, dnsQueryResult]).arrayBuffer());
isVlessHeaderSent = true;
}
}
}
})).catch((error) => {
log(‘dns udp has error’ + error)
});
const writer = transformStream.writable.getWriter();
return {
/**
* 
* @param {Uint8Array} chunk 
*/
write(chunk) {
writer.write(chunk);
}
};
}
/**
 * 
 * @param {string} userID 
 * @param {string | null} hostName
 * @returns {string}
 */
function getVLESSConfig(userID, hostName) {
const vlessMain = `vless://${userID}\u0040${hostName}:443?encryption=none&security=tls&sni=${hostName}&fp=randomized&type=ws&host=${hostName}&path=%2F%3Fed%3D2048#${hostName}`
return `
################################################################
v2ray
—————————————————————
${vlessMain}
—————————————————————
################################################################
clash-meta
—————————————————————
– type: vless
  name: ${hostName}
  server: ${hostName}
  port: 443
  uuid: ${userID}
  network: ws
  tls: true
  udp: false
  sni: ${hostName}
  client-fingerprint: chrome
  ws-opts:
    path: “/?ed=2048”
    headers:
      host: ${hostName}
—————————————————————
################################################################
`;
}