diff --git a/src/protections/WordList.ts b/src/protections/WordList.ts new file mode 100644 index 0000000..7c2842b --- /dev/null +++ b/src/protections/WordList.ts @@ -0,0 +1,88 @@ +/* +Copyright 2019, 2020 The Matrix.org Foundation C.I.C. + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +*/ + +import { IProtection } from "./IProtection"; +import { Mjolnir } from "../Mjolnir"; +import { LogLevel, LogService } from "matrix-bot-sdk"; +import { logMessage } from "../LogProxy"; +import config from "../config"; +import { isTrueJoinEvent } from "../utils"; + +export class WordList implements IProtection { + + private justJoined: { [roomId: string]: { [username: string]: Date} } = {}; + private badWords: RegExp = new RegExp(/.*(poopyhead).*/i) + + constructor() { + } + + public get name(): string { + return 'WordList'; + } + + public async handleEvent(mjolnir: Mjolnir, roomId: string, event: any): Promise { + if (!this.justJoined[roomId]) this.justJoined[roomId] = {}; + + const content = event['content'] || {}; + + // When a new member logs in, store the time they joined. This will be useful + // when we need to check if a message was sent within 20 minutes of joining + if (event['type'] === 'm.room.member') { + if (isTrueJoinEvent(event)) { + const now = new Date(); + this.justJoined[roomId][event['state_key']] = now; + LogService.info("WordList", `${event['state_key']} joined ${roomId} at ${now.toDateString()}`); + } else if (content['membership'] == 'leave' || content['membership'] == 'ban') { + delete this.justJoined[roomId][event['sender']] + } + + return; // stop processing (membership event spam is another problem) + } + + if (event['type'] === 'm.room.message') { + const message = content['formatted_body'] || content['body'] || null; + + const joinTime = this.justJoined[roomId][event['sender']] + if (joinTime) { // Disregard if the user isn't recently joined + + // Check if they did join recently, was it within 20 minutes + const now = new Date(); + if (now.valueOf() - joinTime.valueOf() > 20 * 60 * 1000) { + delete this.justJoined[roomId][event['sender']] // Remove the user + LogService.info("WordList", `${event['sender']} is no longer considered suspect`); + return + } + + // Perform the test + if (message && this.badWords.test(message)) { + await logMessage(LogLevel.WARN, "WordList", `Banning ${event['sender']} for word list violation in ${roomId}.`); + if (!config.noop) { + await mjolnir.client.banUser(event['sender'], roomId, "Word list violation"); + } else { + await logMessage(LogLevel.WARN, "WordList", `Tried to ban ${event['sender']} in ${roomId} but Mjolnir is running in no-op mode`, roomId); + } + + // Redact the event + if (!config.noop) { + await mjolnir.client.redactEvent(roomId, event['event_id'], "spam"); + } else { + await logMessage(LogLevel.WARN, "WordList", `Tried to redact ${event['event_id']} in ${roomId} but Mjolnir is running in no-op mode`, roomId); + } + } + } + } + } +} diff --git a/src/protections/protections.ts b/src/protections/protections.ts index 894a221..612a1b2 100644 --- a/src/protections/protections.ts +++ b/src/protections/protections.ts @@ -17,6 +17,7 @@ limitations under the License. import { FirstMessageIsImage } from "./FirstMessageIsImage"; import { IProtection } from "./IProtection"; import { BasicFlooding, MAX_PER_MINUTE } from "./BasicFlooding"; +import { WordList } from "./WordList"; export const PROTECTIONS: PossibleProtections = { [new FirstMessageIsImage().name]: { @@ -28,6 +29,11 @@ export const PROTECTIONS: PossibleProtections = { description: "If a user posts more than " + MAX_PER_MINUTE + " messages in 60s they'll be " + "banned for spam. This does not publish the ban to any of your ban lists.", factory: () => new BasicFlooding(), + }, + [new WordList().name]: { + description: "If a user posts a monitored word within 20 minutes of joining, they " + + "will be banned from that room. This will not publish the ban to a ban list.", + factory: () => new WordList(), } };