UNTESTED maybe laxer match on authority - fixes #815

packages/backend/src/core/UtilityService.ts

@@ -7,6 +7,7 @@ import { URL } from 'node:url';
 import { toASCII } from 'punycode';
 import { Inject, Injectable } from '@nestjs/common';
 import RE2 from 're2';
+import psl from 'psl';
 import { DI } from '@/di-symbols.js';
 import type { Config } from '@/config.js';
 import { bindThis } from '@/decorators.js';
@@ -122,6 +123,14 @@ export class UtilityService {
 		return host;
 	}
 
+	@bindThis
+	public punyHostPSLDomain(url: string): string {
+		const urlObj = new URL(url);
+		const domain = psl.get(urlObj.hostname) ?? urlObj.hostname;
+		const host = `${this.toPuny(domain)}${urlObj.port.length > 0 ? ':' + urlObj.port : ''}`;
+		return host;
+	}
+
 	public isFederationAllowedHost(host: string): boolean {
 		if (this.meta.federation === 'none') return false;
 		if (this.meta.federation === 'specified' && !this.meta.federationHosts.some(x => `.${host.toLowerCase()}`.endsWith(`.${x}`))) return false;