Files
SRCmail/lib/telemetry/login-tracker.ts
T
2026-04-28 08:19:46 +02:00

126 lines
3.9 KiB
TypeScript

import { readFile, writeFile, mkdir, rename } from 'node:fs/promises';
import { existsSync } from 'node:fs';
import path from 'node:path';
import { createHmac } from 'node:crypto';
import { logger } from '@/lib/logger';
import { getInstanceId } from './state';
// We never store usernames or server URLs in the clear. Each login is
// recorded as HMAC-SHA256(username + '@' + serverUrl, instance_id), so the
// file on disk cannot be cross-correlated with any other instance and is
// not PII even if leaked.
interface LoginRecord {
id: string;
lastLoginAt: string;
}
interface LoginsFile {
records: LoginRecord[];
}
const SEVEN_DAYS_MS = 7 * 24 * 60 * 60 * 1000;
const RETENTION_MS = 90 * 24 * 60 * 60 * 1000;
let cache: LoginsFile | null = null;
function getDir(): string {
return process.env.TELEMETRY_DATA_DIR || path.join(process.cwd(), 'data', 'telemetry');
}
function loginsPath(): string {
return path.join(getDir(), 'logins.json');
}
async function ensureDir(): Promise<void> {
const dir = getDir();
if (!existsSync(dir)) await mkdir(dir, { recursive: true });
}
async function loadFile(): Promise<LoginsFile> {
if (cache) return cache;
try {
const raw = await readFile(loginsPath(), 'utf8');
const parsed = JSON.parse(raw) as Partial<LoginsFile>;
cache = Array.isArray(parsed?.records) ? { records: parsed.records as LoginRecord[] } : { records: [] };
} catch {
cache = { records: [] };
}
return cache;
}
async function saveFile(file: LoginsFile): Promise<void> {
await ensureDir();
cache = file;
const tmp = loginsPath() + '.tmp';
await writeFile(tmp, JSON.stringify(file), 'utf8');
await rename(tmp, loginsPath());
}
function normalizeServer(serverUrl: string): string {
return serverUrl.trim().replace(/\/+$/, '').toLowerCase();
}
async function hashIdentity(username: string, serverUrl: string): Promise<string> {
const instanceId = await getInstanceId();
const subject = `${username.trim().toLowerCase()}@${normalizeServer(serverUrl)}`;
return createHmac('sha256', instanceId).update(subject).digest('hex').slice(0, 32);
}
/**
* Record a successful login. Best-effort; never throws. Updates the
* existing record's timestamp if the same identity has logged in before,
* otherwise appends a new record. Records older than the retention window
* are pruned on every write.
*/
export async function recordLogin(username: string, serverUrl: string): Promise<void> {
if (!username || !serverUrl) return;
try {
const id = await hashIdentity(username, serverUrl);
const file = await loadFile();
const now = new Date().toISOString();
const cutoff = Date.now() - RETENTION_MS;
const next: LoginRecord[] = [];
let updated = false;
for (const rec of file.records) {
const ts = new Date(rec.lastLoginAt).getTime();
if (Number.isNaN(ts) || ts < cutoff) continue;
if (rec.id === id) {
next.push({ id, lastLoginAt: now });
updated = true;
} else {
next.push(rec);
}
}
if (!updated) next.push({ id, lastLoginAt: now });
await saveFile({ records: next });
} catch (err) {
logger.debug?.('telemetry: recordLogin failed', {
error: err instanceof Error ? err.message : String(err),
});
}
}
/**
* Total distinct accounts seen in the 90-day retention window, plus those
* with a login in the last 7 days.
*/
export async function getLoginCounts(): Promise<{ total: number; active7d: number }> {
try {
const file = await loadFile();
const cutoff = Date.now() - RETENTION_MS;
const sevenAgo = Date.now() - SEVEN_DAYS_MS;
let total = 0;
let active7d = 0;
for (const rec of file.records) {
const ts = new Date(rec.lastLoginAt).getTime();
if (Number.isNaN(ts) || ts < cutoff) continue;
total++;
if (ts >= sevenAgo) active7d++;
}
return { total, active7d };
} catch {
return { total: 0, active7d: 0 };
}
}