From d883934826122b64439170c2013d65606fd23184 Mon Sep 17 00:00:00 2001
From: Laura Hausmann <laura@hausmann.dev>
Date: Thu, 24 Oct 2024 05:13:35 +0200
Subject: [PATCH] fix: primitive 2: acceptance of cross-origin alternate links

---
 packages/backend/src/core/activitypub/ApRequestService.ts | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/packages/backend/src/core/activitypub/ApRequestService.ts b/packages/backend/src/core/activitypub/ApRequestService.ts
index 38c78cf900..35eb1a5c53 100644
--- a/packages/backend/src/core/activitypub/ApRequestService.ts
+++ b/packages/backend/src/core/activitypub/ApRequestService.ts
@@ -18,6 +18,7 @@ import type Logger from '@/logger.js';
 import type { IObject } from './type.js';
 import { validateContentTypeSetAsActivityPub } from '@/core/activitypub/misc/validator.js';
 import { assertActivityMatchesUrls } from '@/core/activitypub/misc/check-against-url.js';
+import { UtilityService } from "@/core/UtilityService.js";
 
 type Request = {
 	url: string;
@@ -147,6 +148,7 @@ export class ApRequestService {
 		private userKeypairService: UserKeypairService,
 		private httpRequestService: HttpRequestService,
 		private loggerService: LoggerService,
+		private utilityService: UtilityService,
 	) {
 		// eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 		this.logger = this.loggerService?.getLogger('ap-request'); // なぜか TypeError: Cannot read properties of undefined (reading 'getLogger') と言われる
@@ -241,7 +243,9 @@ export class ApRequestService {
 				if (alternate) {
 					const href = alternate.getAttribute('href');
 					if (href) {
-						return await this.signedGet(href, user, false);
+						if (this.utilityService.punyHost(url) === this.utilityService.punyHost(href)) {
+							return await this.signedGet(href, user, false);
+						}
 					}
 				}
 			} catch (e) {