Files
IdP/apps/api-gateway/src/lib/fedcm-cors.ts
2026-07-01 12:05:34 +03:00

71 lines
2.1 KiB
TypeScript

import { BadRequestException } from '@nestjs/common';
import type { Request, Response } from 'express';
export function normalizeFedcmOrigin(origin?: string) {
return origin?.trim().replace(/\/+$/, '') || undefined;
}
export function applyFedcmCorsHeaders(res: Response, origin?: string) {
const normalized = normalizeFedcmOrigin(origin);
if (!normalized) {
return;
}
res.setHeader('Access-Control-Allow-Origin', normalized);
res.setHeader('Access-Control-Allow-Credentials', 'true');
res.setHeader('Vary', 'Origin');
}
export function requireFedcmCorsOrigin(origin?: string) {
const normalized = normalizeFedcmOrigin(origin);
if (!normalized) {
throw new BadRequestException('FedCM требует заголовок Origin');
}
return normalized;
}
export function applyFedcmPreflightHeaders(res: Response, origin?: string) {
applyFedcmCorsHeaders(res, origin);
res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS');
res.setHeader(
'Access-Control-Allow-Headers',
'Content-Type, Authorization, Sec-Fetch-Dest, Sec-Fetch-Mode, Sec-Fetch-Site'
);
res.setHeader('Access-Control-Max-Age', '86400');
}
/**
* FedCM-запросы должны иметь Sec-Fetch-Dest: webidentity (или empty, если прокси
* не пробрасывает заголовок). Блокируем только явно «не-FedCM» dest (document,
* script, image…) — иначе well-known/config отдают 400 и One Tap ломается.
*/
const BLOCKED_FEDCM_FETCH_DEST = new Set([
'document',
'embed',
'frame',
'iframe',
'object',
'script',
'style',
'image',
'font',
'audio',
'video',
'track',
'worker',
'serviceworker',
'sharedworker',
'manifest',
'xslt'
]);
export function assertFedcmWebIdentityRequest(req: Request) {
const dest = String(req.headers['sec-fetch-dest'] ?? '').toLowerCase();
if (dest && BLOCKED_FEDCM_FETCH_DEST.has(dest)) {
throw new BadRequestException('Недопустимый Sec-Fetch-Dest для FedCM');
}
}
export function applyFedcmLoginStatus(res: Response, loggedIn: boolean) {
res.setHeader('Set-Login', loggedIn ? 'logged-in' : 'logged-out');
}