Challenge/Response is an anti-spam plugin for Adium 1.3+. It works by hiding messages until the user answers a question you have picked. For example, "What is the square root of 49 in numerical form?
" must be responded to with "7
When the user responds correctly, all of the messages that were hidden are displayed as though C/R never did anything, and the user is added to the C/R whitelist so that they will never be asked again.
C/R works by displaying this prompt to unknown users
, which are classified as:
- Users not in your contact list (this excludes AIM's "recent buddies" group),
- Users not in your C/R whitelist, and
- Users you do not have a chat opened with
Since you set the challenge and response, the spam bots won't know what to say.
You can find the C/R preferences in the Adium menu, under Privacy Settings. You must enable C/R and set the challenge and response before it will do anything. If you disable C/R, it will display all the saved messages from users who have not yet answered the question while Adium has been running.
You can optionally log all messages which were hidden by C/R to a group chat called ChallengeResponse (one is created per account, a limitation imposed by the logger plugin currently). You can also hide all messages from blocked users, for protocols like MSN where blocked users can still message you.
The source is available from the Adium Mercurial repository at http://hg.adium.im/plugins/challengeresponse/
- Enable on selective accounts.
- Hide authorization events until after a C/R.
- With MSN, you will sometimes see the "switchboard error" message displayed in the chat window. This is caused by the bot not properly responding to received messages. A future version will prevent their display.
- This does not interact well with "Open chats when typing begins" (psychic option in Advanced>Status) as it will open a chat and auto-whitelist the user. This may not be a problem for spam, depending on if the spammers send typing notifications.