FoundKey/packages/backend/src/remote/activitypub/check-fetch.ts

73 lines
1.8 KiB
TypeScript

import config from '@/config/index.js';
import { IncomingMessage } from 'http';
import { fetchMeta } from '@/misc/fetch-meta.js';
import httpSignature from '@peertube/http-signature';
import { URL } from 'url';
import { toPuny } from '@/misc/convert-host.js';
import DbResolver from '@/remote/activitypub/db-resolver.js';
import { getApId } from '@/remote/activitypub/type.js';
export default async function checkFetch(req: IncomingMessage): Promise<number> {
const meta = await fetchMeta();
if (meta.secureMode || meta.privateMode) {
let signature;
try {
signature = httpSignature.parseRequest(req, { 'headers': [] });
} catch (e) {
return 401;
}
const keyId = new URL(signature.keyId);
const host = toPuny(keyId.hostname);
if (meta.blockedHosts.includes(host)) {
return 403;
}
if (meta.privateMode && host !== config.host && !meta.allowedHosts.includes(host)) {
return 403;
}
const keyIdLower = signature.keyId.toLowerCase();
if (keyIdLower.startsWith('acct:')) {
// Old keyId is no longer supported.
return 401;
}
const dbResolver = new DbResolver();
// HTTP-Signature keyIdを元にDBから取得
let authUser = await dbResolver.getAuthUserFromKeyId(signature.keyId);
// keyIdでわからなければ、resolveしてみる
if (authUser == null) {
try {
keyId.hash = '';
authUser = await dbResolver.getAuthUserFromApId(getApId(keyId.toString()));
} catch (e) {
// できなければ駄目
return 403;
}
}
// publicKey がなくても終了
if (authUser?.key == null) {
return 403;
}
// もう一回チェック
if (authUser.user.host !== host) {
return 403;
}
// HTTP-Signatureの検証
const httpSignatureValidated = httpSignature.verifySignature(signature, authUser.key.keyPem);
if (!httpSignatureValidated) {
return 403;
}
}
return 200;
}