hotfix(backend): GHSA-qqrm-9grj-6v32 (MisskeyIO#460)

* hotfix(backend): GHSA-qqrm-9grj-6v32

Cherry-picked from 9a70ce8f5e

Co-authored-by: tamaina <tamaina@hotmail.co.jp>

* security fix: regexp

Co-authored-by: Ry0taK <49341894+Ry0taK@users.noreply.github.com>

---------

Co-authored-by: tamaina <tamaina@hotmail.co.jp>
Co-authored-by: Ry0taK <49341894+Ry0taK@users.noreply.github.com>

packages/backend/src/core/HttpRequestService.ts

@@ -14,9 +14,16 @@ import { DI } from '@/di-symbols.js';
 import type { Config } from '@/config.js';
 import { StatusError } from '@/misc/status-error.js';
 import { bindThis } from '@/decorators.js';
+import { validateContentTypeSetAsActivityPub } from '@/core/activitypub/misc/validator.js';
+import type { IObject } from '@/core/activitypub/type.js';
 import type { Response } from 'node-fetch';
 import type { URL } from 'node:url';
 
+export type HttpRequestSendOptions = {
+	throwErrorWhenResponseNotOk: boolean;
+	validators?: ((res: Response) => void)[];
+};
+
 @Injectable()
 export class HttpRequestService {
 	/**
@@ -104,6 +111,23 @@ export class HttpRequestService {
 		}
 	}
 
+	@bindThis
+	public async getActivityJson(url: string): Promise<IObject> {
+		const res = await this.send(url, {
+			method: 'GET',
+			headers: {
+				Accept: 'application/activity+json, application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
+			},
+			timeout: 5000,
+			size: 1024 * 256,
+		}, {
+			throwErrorWhenResponseNotOk: true,
+			validators: [validateContentTypeSetAsActivityPub],
+		});
+
+		return await res.json() as IObject;
+	}
+
 	@bindThis
 	public async getJson<T = unknown>(url: string, accept = 'application/json, */*', headers?: Record<string, string>): Promise<T> {
 		const res = await this.send(url, {
@@ -132,17 +156,20 @@ export class HttpRequestService {
 	}
 
 	@bindThis
-	public async send(url: string, args: {
+	public async send(
+		url: string,
+		args: {
 			method?: string,
 			body?: string,
 			headers?: Record<string, string>,
 			timeout?: number,
 			size?: number,
-	} = {}, extra: {
+		} = {},
-		throwErrorWhenResponseNotOk: boolean;
+		extra: HttpRequestSendOptions = {
-	} = {
 			throwErrorWhenResponseNotOk: true,
-	}): Promise<Response> {
+			validators: [],
+		},
+	): Promise<Response> {
 		const timeout = args.timeout ?? 5000;
 
 		const controller = new AbortController();
@@ -169,6 +196,12 @@ export class HttpRequestService {
 			throw new StatusError(`${res.status} ${res.statusText}`, res.status, res.statusText);
 		}
 
+		if (res.ok) {
+			for (const validator of (extra.validators ?? [])) {
+				validator(res);
+			}
+		}
+
 		return res;
 	}
 

packages/backend/src/core/activitypub/ApRequestService.ts

@@ -14,6 +14,7 @@ import { HttpRequestService } from '@/core/HttpRequestService.js';
 import { LoggerService } from '@/core/LoggerService.js';
 import { bindThis } from '@/decorators.js';
 import type Logger from '@/logger.js';
+import { validateContentTypeSetAsActivityPub } from '@/core/activitypub/misc/validator.js';
 
 type Request = {
 	url: string;
@@ -70,7 +71,7 @@ export class ApRequestCreator {
 			url: u.href,
 			method: 'GET',
 			headers: this.#objectAssignWithLcKey({
-				'Accept': 'application/activity+json, application/ld+json',
+				'Accept': 'application/activity+json, application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
 				'Date': new Date().toUTCString(),
 				'Host': new URL(args.url).host,
 			}, args.additionalHeaders),
@@ -195,6 +196,9 @@ export class ApRequestService {
 		const res = await this.httpRequestService.send(url, {
 			method: req.request.method,
 			headers: req.request.headers,
+		}, {
+			throwErrorWhenResponseNotOk: true,
+			validators: [validateContentTypeSetAsActivityPub],
 		});
 
 		return await res.json();

packages/backend/src/core/activitypub/ApResolverService.ts

@@ -105,7 +105,7 @@ export class Resolver {
 
 		const object = (this.user
 			? await this.apRequestService.signedGet(value, this.user) as IObject
-			: await this.httpRequestService.getJson(value, 'application/activity+json, application/ld+json')) as IObject;
+			: await this.httpRequestService.getActivityJson(value)) as IObject;
 
 		if (
 			Array.isArray(object['@context']) ?

packages/backend/src/core/activitypub/LdSignatureService.ts

@@ -8,6 +8,7 @@ import { Injectable } from '@nestjs/common';
 import { HttpRequestService } from '@/core/HttpRequestService.js';
 import { bindThis } from '@/decorators.js';
 import { CONTEXTS } from './misc/contexts.js';
+import { validateContentTypeSetAsJsonLD } from './misc/validator.js';
 import type { JsonLdDocument } from 'jsonld';
 import type { JsonLd, RemoteDocument } from 'jsonld/jsonld-spec.js';
 
@@ -133,7 +134,10 @@ class LdSignature {
 				},
 				timeout: this.loderTimeout,
 			},
-			{ throwErrorWhenResponseNotOk: false },
+			{
+				throwErrorWhenResponseNotOk: false,
+				validators: [validateContentTypeSetAsJsonLD],
+			},
 		).then(res => {
 			if (!res.ok) {
 				throw new Error(`${res.status} ${res.statusText}`);

packages/backend/src/core/activitypub/misc/validator.ts

@@ -0,0 +1,39 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import type { Response } from 'node-fetch';
+
+export function validateContentTypeSetAsActivityPub(response: Response): void {
+	const contentType = (response.headers.get('content-type') ?? '').toLowerCase();
+
+	if (contentType === '') {
+		throw new Error('Validate content type of AP response: No content-type header');
+	}
+	if (
+		contentType.startsWith('application/activity+json') ||
+		(contentType.startsWith('application/ld+json;') && contentType.includes('https://www.w3.org/ns/activitystreams'))
+	) {
+		return;
+	}
+	throw new Error('Validate content type of AP response: Content type is not application/activity+json or application/ld+json');
+}
+
+const plusJsonSuffixRegex = /^\s*(application|text)\/[a-zA-Z0-9\.\-\+]+\+json\s*(;|$)/;
+
+export function validateContentTypeSetAsJsonLD(response: Response): void {
+	const contentType = (response.headers.get('content-type') ?? '').toLowerCase();
+
+	if (contentType === '') {
+		throw new Error('Validate content type of JSON LD: No content-type header');
+	}
+	if (
+		contentType.startsWith('application/ld+json') ||
+		contentType.startsWith('application/json') ||
+		plusJsonSuffixRegex.test(contentType)
+	) {
+		return;
+	}
+	throw new Error('Validate content type of JSON LD: Content type is not application/ld+json or application/json');
+}

packages/backend/test/e2e/fetch-validate-ap-deny.ts

@@ -0,0 +1,40 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+process.env.NODE_ENV = 'test';
+
+import { validateContentTypeSetAsActivityPub, validateContentTypeSetAsJsonLD } from '@/core/activitypub/misc/validator.js';
+import { signup, uploadFile, relativeFetch } from '../utils.js';
+import type * as misskey from 'misskey-js';
+
+describe('validateContentTypeSetAsActivityPub/JsonLD (deny case)', () => {
+	let alice: misskey.entities.SignupResponse;
+	let aliceUploadedFile: any;
+
+	beforeAll(async () => {
+		alice = await signup({ username: 'alice' });
+		aliceUploadedFile = await uploadFile(alice);
+	}, 1000 * 60 * 2);
+
+	test('ActivityStreams: ファイルはエラーになる', async () => {
+		const res = await relativeFetch(aliceUploadedFile.webpublicUrl);
+
+		function doValidate() {
+			validateContentTypeSetAsActivityPub(res);
+		}
+
+		expect(doValidate).toThrow('Content type is not');
+	});
+
+	test('JSON-LD: ファイルはエラーになる', async () => {
+		const res = await relativeFetch(aliceUploadedFile.webpublicUrl);
+
+		function doValidate() {
+			validateContentTypeSetAsJsonLD(res);
+		}
+
+		expect(doValidate).toThrow('Content type is not');
+	});
+});

packages/backend/test/unit/activitypub.ts

@@ -203,7 +203,7 @@ describe('ActivityPub', () => {
 
 	describe('Renderer', () => {
 		test('Render an announce with visibility: followers', () => {
-			rendererService.renderAnnounce(null, {
+			rendererService.renderAnnounce('https://example.com/notes/00example', {
 				id: genAidx(Date.now()),
 				visibility: 'followers',
 			} as MiNote);

packages/backend/test/utils.ts

@@ -15,6 +15,7 @@ import { JSDOM } from 'jsdom';
 import * as Redis from 'ioredis';
 import { DEFAULT_POLICIES } from '@/core/RoleService.js';
 import { Packed } from '@/misc/json-schema.js';
+import { validateContentTypeSetAsActivityPub } from '@/core/activitypub/misc/validator.js';
 import { entities } from '@/postgres.js';
 import { loadConfig } from '@/config.js';
 import type * as misskey from 'misskey-js';
@@ -328,7 +329,6 @@ export const uploadFile = async (user?: UserToken, { path, name, blob }: UploadO
 	});
 
 	const body = res.status !== 204 ? await res.json() as misskey.Endpoints['drive/files/create']['res'] : null;
-
 	return {
 		status: res.status,
 		headers: res.headers,
@@ -477,6 +477,14 @@ export const simpleGet = async (path: string, accept = '*/*', cookie: any = unde
 		'text/html; charset=utf-8',
 	];
 
+	if (res.ok && (
+		accept.startsWith('application/activity+json') ||
+		(accept.startsWith('application/ld+json') && accept.includes('https://www.w3.org/ns/activitystreams'))
+	)) {
+		// validateContentTypeSetAsActivityPubのテストを兼ねる
+		validateContentTypeSetAsActivityPub(res);
+	}
+
 	const body =
 		jsonTypes.includes(res.headers.get('content-type') ?? '') ? await res.json() :
 		htmlTypes.includes(res.headers.get('content-type') ?? '') ? new JSDOM(await res.text()) :