diff options
| -rw-r--r-- | bot/__main__.py | 1 | ||||
| -rw-r--r-- | bot/cogs/webhook_remover.py | 72 |
2 files changed, 73 insertions, 0 deletions
diff --git a/bot/__main__.py b/bot/__main__.py index 3df477a6d..8c3ae02e3 100644 --- a/bot/__main__.py +++ b/bot/__main__.py @@ -63,6 +63,7 @@ bot.load_extension("bot.cogs.tags") bot.load_extension("bot.cogs.token_remover") bot.load_extension("bot.cogs.utils") bot.load_extension("bot.cogs.watchchannels") +bot.load_extension("bot.cogs.webhook_remover") bot.load_extension("bot.cogs.wolfram") # Apply `message_edited_at` patch if discord.py did not yet release a bug fix. diff --git a/bot/cogs/webhook_remover.py b/bot/cogs/webhook_remover.py new file mode 100644 index 000000000..49692113d --- /dev/null +++ b/bot/cogs/webhook_remover.py @@ -0,0 +1,72 @@ +import logging +import re + +from discord import Colour, Message +from discord.ext.commands import Cog + +from bot.bot import Bot +from bot.cogs.moderation.modlog import ModLog +from bot.constants import Channels, Colours, Event, Icons + +WEBHOOK_URL_RE = re.compile(r"((?:https?://)?discordapp\.com/api/webhooks/\d+/)\S+/?", re.I) + +ALERT_MESSAGE_TEMPLATE = ( + "{user}, looks like you posted a Discord webhook URL. Therefore, your " + "message has been removed. Your webhook may have been **compromised** so " + "please re-create the webhook **immediately**. If you believe this was " + "mistake, please let us know." +) + +log = logging.getLogger(__name__) + + +class WebhookRemover(Cog): + """Scan messages to detect Discord webhooks links.""" + + def __init__(self, bot: Bot): + self.bot = bot + + @property + def mod_log(self) -> ModLog: + """Get current instance of `ModLog`.""" + return self.bot.get_cog("ModLog") + + async def delete_and_respond(self, msg: Message, redacted_url: str) -> None: + """Delete `msg` and send a warning that it contained the Discord webhook `redacted_url`.""" + # Don't log this, due internal delete, not by user. Will make different entry. + self.mod_log.ignore(Event.message_delete, msg.id) + await msg.delete() + await msg.channel.send(ALERT_MESSAGE_TEMPLATE.format(user=msg.author.mention)) + + message = ( + f"{msg.author} (`{msg.author.id}`) posted a Discord webhook URL " + f"to #{msg.channel}. Webhook URL was `{redacted_url}`" + ) + log.debug(message) + + # Send entry to moderation alerts. + await self.mod_log.send_log_message( + icon_url=Icons.token_removed, + colour=Colour(Colours.soft_red), + title="Discord webhook URL removed!", + text=message, + thumbnail=msg.author.avatar_url_as(static_format="png"), + channel_id=Channels.mod_alerts + ) + + @Cog.listener() + async def on_message(self, msg: Message) -> None: + """Check if a Discord webhook URL is in `message`.""" + matches = WEBHOOK_URL_RE.search(msg.content) + if matches: + await self.delete_and_respond(msg, matches[1] + "xxx") + + @Cog.listener() + async def on_message_edit(self, before: Message, after: Message) -> None: + """Check if a Discord webhook URL is in the edited message `after`.""" + await self.on_message(after) + + +def setup(bot: Bot) -> None: + """Load `WebhookRemover` cog.""" + bot.add_cog(WebhookRemover(bot)) |