Files
gists/scripts/proxy/bridge.test.js
T
tke c514f32661 feat(proxy): credential-failure backoff prevents corp proxy account lockout
After 3 consecutive 407s within 120s (defaults; env-tunable), the bridge stops
sending Proxy-Authorization to that upstream for 300s, then retries once with
refreshed keyring creds. A successful request clears the failure state. Requests
during the lockout fail fast with the upstream's 407 instead of retrying stale
credentials — the exact pattern that locks accounts.

Tests: 407-stub lockout engages on 4th attempt; success mid-stream resets the
counter (re-lock needs a fresh 3); missing creds never send an auth header.
Harness: awaitProxyResponse() decouples client-side settle from server FIN
timing (previous once(end) pattern wedged under node --test).
2026-09-23 14:57:18 +02:00

450 lines
20 KiB
JavaScript

const assert = require('node:assert/strict');
const { once } = require('node:events');
const fs = require('node:fs');
const http = require('node:http');
const net = require('node:net');
const path = require('node:path');
const { test } = require('node:test');
const tls = require('node:tls');
const vm = require('node:vm');
const source = fs.readFileSync(path.join(__dirname, 'bridge.js'), 'utf8');
async function listen(t, server) {
const sockets = new Set();
server.on('connection', socket => {
sockets.add(socket);
socket.on('close', () => sockets.delete(socket));
});
t.after(() => {
for (const socket of sockets) socket.destroy();
server.close();
});
server.listen(0, '127.0.0.1');
await once(server, 'listening');
return server.address().port;
}
async function bridge(t, upstreamPort, upstreamCfg) {
const servers = [];
const env = { ...process.env, ...(upstreamCfg && upstreamCfg.env ? upstreamCfg.env : {}) };
// Isolate routing, credentials and listeners from the user's installed service.
vm.runInNewContext(source, {
Buffer, URL, console: { log() {} }, setTimeout, clearTimeout,
process: { env },
require(name) {
if (name === 'fs') return {
readFileSync: () => JSON.stringify(upstreamCfg
? { enabled: true, host: upstreamCfg.host, port: upstreamCfg.port }
: upstreamPort
? { enabled: true, host: '127.0.0.1', port: upstreamPort }
: { enabled: false }),
existsSync: () => false,
watchFile() {},
};
if (name === 'child_process') return { execFileSync: () => '' };
if (name === 'http') return {
...http,
createServer(...args) {
const server = http.createServer(...args);
server.listen = () => { servers.push(server); return server; };
return server;
},
};
return require(name);
},
}, { filename: 'bridge.js' });
const server = servers[0];
server.listen = net.Server.prototype.listen;
return listen(t, server);
}
// Start the bridge with env overrides and return the ephemeral port of a chosen
// listenerProfile ('dynamic', 'internet', or a PAC profile name). All listeners
// are tracked for cleanup; only the requested one is bound to a random port.
async function bridgeOnProfile(t, listenerProfile, { upstreamCfg, env = {}, withCreds = false } = {}) {
const servers = [];
const fullEnv = { ...process.env, ...env };
vm.runInNewContext(source, {
Buffer, URL, console: { log() {} }, setTimeout, clearTimeout,
process: { env: fullEnv },
require(name) {
if (name === 'fs') return {
readFileSync: (p) => {
// Bridge config file -> upstreamCfg
if (typeof p === 'string' && p.includes('config.json')) {
return JSON.stringify(upstreamCfg || { enabled: false });
}
if (typeof p === 'string' && p.includes('user.json')) {
if (!withCreds) throw new Error('ENOENT: no user.json in test');
return JSON.stringify({ username: 'test-user' });
}
// PAC files and everything else fall through to the REAL fs
return fs.readFileSync(p, 'utf8');
},
existsSync: (p) => {
if (typeof p === 'string') {
if (p.includes('user.json')) return withCreds;
// Isolate runtime state files from the user's live installation;
// everything else (PAC dir etc.) uses the real fs.
if (p.includes('profile.json') || p.includes('overrides.json') || p.includes('remotes.json')) return false;
}
return fs.existsSync(p);
},
readdirSync: fs.readdirSync,
watchFile() {},
};
if (name === 'child_process') return {
execFileSync: (cmd, args) => {
// secret-tool lookup -> fake standing creds when withCreds, else empty
if (Array.isArray(args) && args[0] === 'lookup' && withCreds) return 'test-password\n';
return '';
},
};
if (name === 'http') return {
...http,
createServer(...args) {
const server = http.createServer(...args);
server.listen = () => { servers.push(server); return server; };
return server;
},
};
return require(name);
},
}, { filename: 'bridge.js' });
// Listener creation order: index 0 = dynamic; then getAvailableProfiles()
// order = internet (if enabled), direct, off, then PAC profiles (readdir order).
const names = ['dynamic'];
if (!upstreamCfg || upstreamCfg.enabled !== false) names.push('internet');
names.push('direct', 'off');
const pacDir = env.PROXY_BRIDGE_PAC_DIR || path.join(require('os').homedir(), '.mozilla');
if (fs.existsSync(pacDir)) {
for (const f of fs.readdirSync(pacDir)) if (f.endsWith('.pac')) names.push(f.slice(0, -4));
}
const idx = names.indexOf(listenerProfile);
if (idx === -1 || !servers[idx]) throw new Error(`listener '${listenerProfile}' not created; have ${names.join(',')}`);
for (let i = 0; i < servers.length; i++) {
if (i !== idx && servers[i].listening === false) { /* never actually listened */ }
}
const server = servers[idx];
server.listen = net.Server.prototype.listen;
return listen(t, server);
}
async function connect(t, port, initial = '') {
const socket = net.connect(port, '127.0.0.1');
t.after(() => socket.destroy());
await once(socket, 'connect');
socket.write(`CONNECT example.test:443 HTTP/1.1\r\nHost: example.test:443\r\n\r\n${initial}`);
return socket;
}
function readUntil(socket, predicate) {
return new Promise((resolve, reject) => {
let data = Buffer.alloc(0);
const cleanup = () => {
socket.off('data', onData);
socket.off('end', onEnd);
socket.off('error', onError);
};
const onData = chunk => {
data = Buffer.concat([data, chunk]);
if (predicate(data)) { cleanup(); resolve(data); }
};
const onEnd = () => { cleanup(); reject(new Error(`Unexpected EOF: ${data.toString()}`)); };
const onError = error => { cleanup(); reject(error); };
socket.on('data', onData);
socket.on('end', onEnd);
socket.on('error', onError);
});
}
test('CONNECT buffers fragmented upstream headers and preserves tunnel bytes', { timeout: 3000 }, async t => {
const upstreamPort = await listen(t, net.createServer(socket => {
socket.once('data', () => {
socket.write('HT');
setTimeout(() => socket.write('TP/1.1 200 OK\r\nX-Proxy: test\r\n'), 30);
setTimeout(() => socket.write('\r\nserver-data'), 60);
});
}));
const socket = await connect(t, await bridge(t, upstreamPort));
const data = await readUntil(socket, data => data.includes('server-data'));
assert.equal(data.toString(), 'HTTP/1.1 200 Connection Established\r\n\r\nserver-data');
});
test('CONNECT forwards client head and a large payload without corruption', { timeout: 5000 }, async t => {
const upstreamPort = await listen(t, net.createServer(socket => {
socket.once('data', () => {
socket.write('HTTP/1.1 200 OK\r\n\r\n');
socket.pipe(socket);
});
}));
const socket = await connect(t, await bridge(t, upstreamPort), 'early-data');
const initial = await readUntil(socket, data => data.includes('early-data'));
assert.equal(initial.toString(), 'HTTP/1.1 200 Connection Established\r\n\r\nearly-data');
const payload = Buffer.alloc(4 * 1024 * 1024, 'x');
const received = readUntil(socket, data => data.length >= payload.length);
socket.write(payload);
assert.deepEqual(await received, payload);
});
test('upstream reset closes an established tunnel without injecting HTTP', { timeout: 3000 }, async t => {
const upstreamPort = await listen(t, net.createServer(socket => {
socket.once('data', () => {
socket.write('HTTP/1.1 200 OK\r\n\r\n');
socket.once('data', () => socket.resetAndDestroy());
});
}));
const socket = await connect(t, await bridge(t, upstreamPort));
await readUntil(socket, data => data.includes('\r\n\r\n'));
const chunks = [];
socket.on('data', data => chunks.push(data));
const ended = once(socket, 'end');
socket.write('trigger-reset');
await ended;
assert.equal(Buffer.concat(chunks).length, 0);
});
test('upstream EOF before CONNECT completes does not leave client hanging', { timeout: 3000 }, async t => {
const upstreamPort = await listen(t, net.createServer(socket => {
socket.once('data', () => socket.end('HTTP/1.1 200'));
}));
const socket = await connect(t, await bridge(t, upstreamPort));
const ended = once(socket, 'end');
const data = await readUntil(socket, data => data.includes('\r\n\r\n'));
assert.match(data.toString(), /^HTTP\/1.1 502 /);
await ended;
});
test('HTTP streams large request bodies and delayed SSE responses', { timeout: 5000 }, async t => {
const payload = Buffer.alloc(4 * 1024 * 1024, 'x');
const targetPort = await listen(t, http.createServer(async (req, res) => {
const chunks = [];
for await (const chunk of req) chunks.push(chunk);
assert.deepEqual(Buffer.concat(chunks), payload);
res.writeHead(200, { 'Content-Type': 'text/event-stream' });
res.write('data: first\n\n');
setTimeout(() => res.end('data: [DONE]\n\n'), 100);
}));
const proxyPort = await bridge(t);
const body = await new Promise((resolve, reject) => {
const req = http.request({ host: '127.0.0.1', port: proxyPort, method: 'POST',
path: `http://127.0.0.1:${targetPort}/chat`, headers: { 'Content-Length': payload.length } }, async res => {
try {
const chunks = [];
for await (const chunk of res) chunks.push(chunk);
resolve(Buffer.concat(chunks).toString());
} catch (error) { reject(error); }
});
req.on('error', reject);
req.end(payload);
});
assert.equal(body, 'data: first\n\ndata: [DONE]\n\n');
});
test('truncated HTTP responses abort the client stream', { timeout: 3000 }, async t => {
const targetPort = await listen(t, http.createServer((req, res) => {
res.writeHead(200, { 'Content-Type': 'text/event-stream' });
res.write('data: partial\n\n');
setTimeout(() => res.destroy(), 30);
}));
const proxyPort = await bridge(t);
await new Promise((resolve, reject) => {
const req = http.get({ host: '127.0.0.1', port: proxyPort,
path: `http://127.0.0.1:${targetPort}/chat` }, res => {
res.resume();
res.on('aborted', resolve);
res.on('error', () => {});
res.on('end', () => reject(new Error('Truncated stream appeared successful')));
});
req.on('error', reject);
});
});
test('DIRECT CONNECT tunnels bytes exactly once when upstream is disabled', { timeout: 3000 }, async t => {
// Upstream disabled -> routing degrades to DIRECT to the CONNECT target.
const target = net.createServer(socket => socket.pipe(socket));
const targetPort = await listen(t, target);
const proxyPort = await bridge(t); // no upstreamPort => { enabled: false }
const socket = net.connect(proxyPort, '127.0.0.1');
t.after(() => socket.destroy());
await once(socket, 'connect');
socket.write(`CONNECT 127.0.0.1:${targetPort} HTTP/1.1\r\nHost: 127.0.0.1:${targetPort}\r\n\r\nearly-bytes`);
const chunks = [];
socket.on('data', d => chunks.push(d));
// Wait for establishment, then exercise the tunnel bidirectionally.
const banner = await readUntil(socket, d => d.includes('early-bytes'));
const occurrences = banner.toString().split('HTTP/1.1 200 Connection Established').length - 1;
assert.equal(occurrences, 1, `expected exactly one 200 banner, got: ${JSON.stringify(banner.toString())}`);
assert.equal(banner.toString(), 'HTTP/1.1 200 Connection Established\r\n\r\nearly-bytes');
socket.write('ping');
const echo = await readUntil(socket, d => d.length >= 4 && d.subarray(-4).toString() === 'ping');
assert.ok(Buffer.concat(chunks).toString().includes('ping'));
assert.equal(Buffer.concat([banner, echo]).includes('ping\r\nping'), false);
});
// Throwaway self-signed fixture (CN=127.0.0.1, generated for tests only, no real identity).
// Regenerate with: openssl req -x509 -newkey rsa:2048 -keyout k.pem -out c.pem -days 3650 -nodes -subj /CN=127.0.0.1
const TLS_FIXTURE = {
key: fs.readFileSync(path.join(__dirname, 'fixtures', 'tls-key.pem'), 'utf8'),
cert: fs.readFileSync(path.join(__dirname, 'fixtures', 'tls-cert.pem'), 'utf8'),
};
test('HTTPS upstream TLS-wraps the CONNECT handshake', { timeout: 5000 }, async t => {
let sawTls = false;
let sawConnect = false;
const upstream = tls.createServer(TLS_FIXTURE, socket => {
sawTls = true;
let buf = Buffer.alloc(0);
socket.on('data', d => {
buf = Buffer.concat([buf, d]);
if (buf.includes('\r\n\r\n')) {
sawConnect = buf.toString().startsWith('CONNECT 127.0.0.1:');
socket.write('HTTP/1.1 200 OK\r\n\r\n');
socket.pipe(socket); // echo tunnel payload back
}
});
});
const upstreamPort = await listen(t, upstream);
// Local PAC dir containing exactly one profile whose FindProxyForURL returns
// an HTTPS directive — exercises PAC eval -> parseProxyConfig('HTTPS ...') -> tls.connect.
const pacDir = fs.mkdtempSync(path.join(require('os').tmpdir(), 'bridge-pac-'));
t.after(() => fs.rmSync(pacDir, { recursive: true, force: true }));
fs.writeFileSync(path.join(pacDir, 'testhttps.pac'),
`function FindProxyForURL() { return "HTTPS 127.0.0.1:${upstreamPort}"; }`);
const proxyPort = await bridgeOnProfile(t, 'testhttps', {
upstreamCfg: { enabled: true, host: '127.0.0.1', port: upstreamPort },
env: { PROXY_BRIDGE_PAC_DIR: pacDir },
});
const echoTarget = await listen(t, net.createServer(s => s.pipe(s)));
const socket = net.connect(proxyPort, '127.0.0.1');
t.after(() => socket.destroy());
await once(socket, 'connect');
socket.write(`CONNECT 127.0.0.1:${echoTarget} HTTP/1.1\r\nHost: 127.0.0.1:${echoTarget}\r\n\r\n`);
const banner = await readUntil(socket, d => d.includes('\r\n\r\n'));
assert.equal(banner.toString(), 'HTTP/1.1 200 Connection Established\r\n\r\n');
socket.write('tls-tunnel-probe');
await readUntil(socket, d => d.includes('tls-tunnel-probe'));
assert.ok(sawTls, 'bridge must speak TLS to an HTTPS upstream');
assert.ok(sawConnect, 'bridge must send CONNECT inside the TLS tunnel');
});
// --- Credential-failure backoff (anti-lockout) ---
// A corp proxy that answers 407 to authed CONNECT. The bridge must give up
// sending Proxy-Authorization after consecutive failures instead of hammering.
function connectWithAuthCapture(t, port) {
// One CONNECT through the bridge; returns the client socket (ended by upstream 407).
const socket = net.connect(port, '127.0.0.1');
t.after(() => socket.destroy());
return once(socket, 'connect').then(() => {
socket.write('CONNECT example.test:443 HTTP/1.1\r\nHost: example.test:443\r\n\r\n');
return socket;
});
}
// Wait until the client socket has seen one full proxy response head, then settle:
// covers both graceful end and destroy paths without depending on FIN timing.
function awaitProxyResponse(socket) {
return new Promise((resolve) => {
let buf = Buffer.alloc(0);
const done = () => resolve(buf);
const onData = (d) => {
buf = Buffer.concat([buf, d]);
if (buf.includes('\r\n\r\n')) {
socket.off('data', onData);
// give the close path one tick, but don't hang on it
setTimeout(done, 25);
}
};
socket.on('data', onData);
socket.once('end', () => setTimeout(done, 25));
socket.once('close', done);
setTimeout(done, 2000); // absolute cap: never wedge the suite
});
}
test('after 3 consecutive 407s the bridge stops sending Proxy-Authorization', { timeout: 5000 }, async t => {
const authHeadersSeen = [];
const upstream = net.createServer(socket => {
socket.once('data', d => {
authHeadersSeen.push(/^Proxy-Authorization:/mi.test(d.toString()));
socket.end('HTTP/1.1 407 Proxy Authentication Required\r\nProxy-Authenticate: Basic realm="corp"\r\n\r\n');
});
});
const upstreamPort = await listen(t, upstream);
const proxyPort = await bridgeOnProfile(t, 'internet', {
upstreamCfg: { enabled: true, host: '127.0.0.1', port: upstreamPort },
withCreds: true,
});
for (let i = 0; i < 4; i++) {
const socket = await connectWithAuthCapture(t, proxyPort);
await awaitProxyResponse(socket); // upstream 407 is relayed then closed
}
assert.deepEqual(authHeadersSeen, [true, true, true, false],
'attempts 1-3 carry auth (optimistic), attempt 4 must not (lockout engaged)');
});
test('a 200 response after failures resets the lockout so auth resumes', { timeout: 5000 }, async t => {
const authHeadersSeen = [];
let calls = 0;
const upstream = net.createServer(socket => {
socket.once('data', d => {
authHeadersSeen.push(/^Proxy-Authorization:/mi.test(d.toString()));
calls++;
// 407 twice (below threshold), then 200 once (clears), then 407 x3 (re-locks), then observe
if (calls <= 2 || calls > 3) {
socket.end('HTTP/1.1 407 Proxy Authentication Required\r\n\r\n');
} else {
socket.write('HTTP/1.1 200 OK\r\n\r\n');
socket.pipe(socket);
}
});
});
const upstreamPort = await listen(t, upstream);
const proxyPort = await bridgeOnProfile(t, 'internet', {
upstreamCfg: { enabled: true, host: '127.0.0.1', port: upstreamPort },
withCreds: true,
});
// 2 fail (count=2), 1 success (clears), 3 fail (re-lock at 3), final observe
for (let i = 0; i < 7; i++) {
const socket = await connectWithAuthCapture(t, proxyPort);
await awaitProxyResponse(socket);
}
assert.deepEqual(authHeadersSeen, [true, true, true, true, true, true, false],
'success mid-stream resets the counter; re-lock needs a fresh 3 consecutive 407s');
});
test('missing credentials never produce an auth header and do not crash the bridge', { timeout: 5000 }, async t => {
const authHeadersSeen = [];
const upstream = net.createServer(socket => {
socket.once('data', d => {
authHeadersSeen.push(/^Proxy-Authorization:/mi.test(d.toString()));
socket.write('HTTP/1.1 200 OK\r\n\r\n');
socket.pipe(socket);
});
});
const upstreamPort = await listen(t, upstream);
const proxyPort = await bridgeOnProfile(t, 'internet', {
upstreamCfg: { enabled: true, host: '127.0.0.1', port: upstreamPort },
withCreds: false, // no user.json, empty keyring
});
for (let i = 0; i < 3; i++) {
const socket = await connectWithAuthCapture(t, proxyPort);
await readUntil(socket, d => d.includes('200'));
socket.destroy();
}
assert.deepEqual(authHeadersSeen, [false, false, false]);
});