ActivityPubでリモートのオブジェクトをGETするときのリクエストをHTTP Signatureで署名するオプション (#6731)

* Sign ActivityPub GET

* Fix v12, v12.48.0 UI bug

7 files changed, 141 insertions, 7 deletions

diff --git a/src/client/pages/follow.vue b/src/client/pages/follow.vue
index 35d5cc3b26..13e0a62a0d 100644
--- a/src/client/pages/follow.vue
+++ b/src/client/pages/follow.vue
@@ -12,6 +12,7 @@ export default defineComponent({
 		const acct = new URL(location.href).searchParams.get('acct');
 		if (acct == null) return;
 
+		/*
 		const dialog = os.dialog({
 			type: 'waiting',
 			text: this.$t('fetchingAsApObject') + '...',
@@ -19,6 +20,7 @@ export default defineComponent({
 			showCancelButton: false,
 			cancelableByBgClick: false
 		});
+		*/
 
 		if (acct.startsWith('https://')) {
 			os.api('ap/show', {
@@ -26,6 +28,8 @@ export default defineComponent({
 			}).then(res => {
 				if (res.type == 'User') {
 					this.follow(res.object);
+				} else if (res.type === 'Note') {
+					this.$router.push(`/notes/${res.object.id}`);
 				} else {
 					os.dialog({
 						type: 'error',
@@ -42,7 +46,7 @@ export default defineComponent({
 					window.close();
 				});
 			}).finally(() => {
-				dialog.close();
+				//dialog.close();
 			});
 		} else {
 			os.api('users/show', parseAcct(acct)).then(user => {
@@ -55,7 +59,7 @@ export default defineComponent({
 					window.close();
 				});
 			}).finally(() => {
-				dialog.close();
+				//dialog.close();
 			});
 		}
 	},
diff --git a/src/client/scripts/search.ts b/src/client/scripts/search.ts
index 45cc691fe4..fbdc32dfb1 100644
--- a/src/client/scripts/search.ts
+++ b/src/client/scripts/search.ts
@@ -48,6 +48,7 @@ export async function search(q?: string | null | undefined) {
 	}
 
 	if (q.startsWith('https://')) {
+		/*
 		const dialog = os.dialog({
 			type: 'waiting',
 			text: i18n.global.t('fetchingAsApObject') + '...',
@@ -55,19 +56,20 @@ export async function search(q?: string | null | undefined) {
 			showCancelButton: false,
 			cancelableByBgClick: false
 		});
+		*/
 
 		try {
 			const res = await os.api('ap/show', {
 				uri: q
 			});
-			dialog.cancel();
+			//dialog.cancel();
 			if (res.type === 'User') {
 				router.push(`/@${res.object.username}@${res.object.host}`);
 			} else if (res.type === 'Note') {
 				router.push(`/notes/${res.object.id}`);
 			}
 		} catch (e) {
-			dialog.cancel();
+			//dialog.cancel();
 			// TODO: Show error
 		}
 
diff --git a/src/config/types.ts b/src/config/types.ts
index 4f025750b0..8084be1864 100644
--- a/src/config/types.ts
+++ b/src/config/types.ts
@@ -58,6 +58,8 @@ export type Source = {
 	};
 
 	mediaProxy?: string;
+
+	signToActivityPubGet?: boolean;
 };
 
 /**
diff --git a/src/misc/fetch.ts b/src/misc/fetch.ts
index 7be0e53fd4..90d89a4392 100644
--- a/src/misc/fetch.ts
+++ b/src/misc/fetch.ts
@@ -5,6 +5,7 @@ import fetch, { HeadersInit } from 'node-fetch';
 import { HttpProxyAgent } from 'http-proxy-agent';
 import { HttpsProxyAgent } from 'https-proxy-agent';
 import config from '../config';
+import { URL } from 'url';
 
 export async function getJson(url: string, accept = 'application/json, */*', timeout = 10000, headers?: HeadersInit) {
 	const res = await fetch(url, {
@@ -69,14 +70,14 @@ const _https = new https.Agent({
  * Get http proxy or non-proxy agent
  */
 export const httpAgent = config.proxy
-	? new HttpProxyAgent(config.proxy)
+	? new HttpProxyAgent(config.proxy) as unknown as http.Agent
 	: _http;
 
 /**
  * Get https proxy or non-proxy agent
  */
 export const httpsAgent = config.proxy
-	? new HttpsProxyAgent(config.proxy)
+	? new HttpsProxyAgent(config.proxy) as unknown as https.Agent
 	: _https;
 
 /**
diff --git a/src/remote/activitypub/request.ts b/src/remote/activitypub/request.ts
index ab51fdd93c..0edfcee1e3 100644
--- a/src/remote/activitypub/request.ts
+++ b/src/remote/activitypub/request.ts
@@ -1,3 +1,4 @@
+import * as http from 'http';
 import * as https from 'https';
 import { sign } from 'http-signature';
 import * as crypto from 'crypto';
@@ -7,6 +8,9 @@ import { ILocalUser } from '../../models/entities/user';
 import { UserKeypairs } from '../../models';
 import { ensure } from '../../prelude/ensure';
 import { getAgentByUrl } from '../../misc/fetch';
+import { URL } from 'url';
+import got from 'got';
+import * as Got from 'got';
 
 export default async (user: ILocalUser, url: string, object: any) => {
 	const timeout = 10 * 1000;
@@ -62,3 +66,96 @@ export default async (user: ILocalUser, url: string, object: any) => {
 		req.end(data);
 	});
 };
+
+/**
+ * Get AP object with http-signature
+ * @param user http-signature user
+ * @param url URL to fetch
+ */
+export async function signedGet(url: string, user: ILocalUser) {
+	const timeout = 10 * 1000;
+
+	const keypair = await UserKeypairs.findOne({
+		userId: user.id
+	}).then(ensure);
+
+	const req = got.get<any>(url, {
+		headers: {
+			'Accept': 'application/activity+json, application/ld+json',
+			'User-Agent': config.userAgent,
+		},
+		responseType: 'json',
+		timeout,
+		hooks: {
+			beforeRequest: [
+				options => {
+					options.request = (url: URL, opt: http.RequestOptions, callback?: (response: any) => void) => {
+						// Select custom agent by URL
+						opt.agent = getAgentByUrl(url, false);
+
+						// Wrap original https?.request
+						const requestFunc = url.protocol === 'http:' ? http.request : https.request;
+						const clientRequest = requestFunc(url, opt, callback) as http.ClientRequest;
+
+						// HTTP-Signature
+						sign(clientRequest, {
+							authorizationHeaderName: 'Signature',
+							key: keypair.privateKey,
+							keyId: `${config.url}/users/${user.id}#main-key`,
+							headers: ['(request-target)', 'host', 'date', 'accept']
+						});
+
+						return clientRequest;
+					};
+				},
+			],
+		},
+		retry: 0,
+	});
+
+	const res = await receiveResponce(req, 10 * 1024 * 1024);
+
+	return res.body;
+}
+
+/**
+ * Receive response (with size limit)
+ * @param req Request
+ * @param maxSize size limit
+ */
+export async function receiveResponce<T>(req: Got.CancelableRequest<Got.Response<T>>, maxSize: number) {
+	// 応答ヘッダでサイズチェック
+	req.on('response', (res: Got.Response) => {
+		const contentLength = res.headers['content-length'];
+		if (contentLength != null) {
+			const size = Number(contentLength);
+			if (size > maxSize) {
+				req.cancel();
+			}
+		}
+	});
+
+	// 受信中のデータでサイズチェック
+	req.on('downloadProgress', (progress: Got.Progress) => {
+		if (progress.transferred > maxSize) {
+			req.cancel();
+		}
+	});
+
+	// 応答取得 with ステータスコードエラーの整形
+	const res = await req.catch(e => {
+		if (e.name === 'HTTPError') {
+			const statusCode = (e as Got.HTTPError).response.statusCode;
+			const statusMessage = (e as Got.HTTPError).response.statusMessage;
+			throw {
+				name: `StatusError`,
+				statusCode,
+				message: `${statusCode} ${statusMessage}`,
+			};
+		} else {
+			throw e;
+		}
+	});
+
+	return res;
+}
diff --git a/src/remote/activitypub/resolver.ts b/src/remote/activitypub/resolver.ts
index f4bf8f94f9..2871c1cb41 100644
--- a/src/remote/activitypub/resolver.ts
+++ b/src/remote/activitypub/resolver.ts
@@ -1,8 +1,13 @@
+import config from '../../config';
 import { getJson } from '../../misc/fetch';
+import { ILocalUser } from '../../models/entities/user';
+import { getInstanceActor } from '../../services/instance-actor';
+import { signedGet } from './request';
 import { IObject, isCollectionOrOrderedCollection, ICollection, IOrderedCollection } from './type';
 
 export default class Resolver {
 	private history: Set<string>;
+	private user?: ILocalUser;
 
 	constructor() {
 		this.history = new Set();
@@ -39,7 +44,13 @@ export default class Resolver {
 
 		this.history.add(value);
 
-		const object = await getJson(value, 'application/activity+json, application/ld+json');
+		if (config.signToActivityPubGet && !this.user) {
+			this.user = await getInstanceActor();
+		}
+
+		const object = this.user
+			? await signedGet(value, this.user)
+			: await getJson(value, 'application/activity+json, application/ld+json');
 
 		if (object == null || (
 			Array.isArray(object['@context']) ?
diff --git a/src/services/instance-actor.ts b/src/services/instance-actor.ts
new file mode 100644
index 0000000000..74591846fa
--- /dev/null
+++ b/src/services/instance-actor.ts
@@ -0,0 +1,17 @@
+import { createSystemUser } from './create-system-user';
+import { ILocalUser } from '../models/entities/user';
+import { Users } from '../models';
+
+const ACTOR_USERNAME = 'instance.actor' as const;
+
+export async function getInstanceActor(): Promise<ILocalUser> {
+	const user = await Users.findOne({
+		host: null,
+		username: ACTOR_USERNAME
+	});
+
+	if (user) return user as ILocalUser;
+
+	const created = await createSystemUser(ACTOR_USERNAME);
+	return created as ILocalUser;
+}