#157 Special Ascii characters in channel names allow duplicates

Server (143)
Jared Smith

This is a bug that allows people to join channels that seem to be like another channel for example.
If you enter in the channel name and then in xchat in linux hit ctrl+shift+u then enter code feff hit enter then enter again to join the channel you will see the problem. I join #darkbot then I join #darkbotctrl+shift+ufeff. Then do a whois and you see.

Notice #darkbot and #darkbot.

* [juice-] (~juice@ juice
* [juice-] #coder-com #darkbot #darkbot
* [juice-] SantaAna.CA.US.Undernet.org :Krypt Technologies Inc.
* [juice-] idle 00:00:37, signon: Sat Aug 15 14:10:45
* [juice-] End of WHOIS list.

This could confuse users when trying to join help channels or any channel in general. It could be possible for malicious users to create rouge channels that could trick users. The more advance users would spot this trick but newer users might not. These characters aren't allowed in nicknames so I think it would be wise to disallow them in #channelnames also.

Freenode simply tells you it's an invalid channel.
* #darkbot :Illegal channel name

Or you could just have it disregard the special characters and have it take the user to the intended channel.

Hopefully this makes sense. If not please ask me on Undernet. Nickname is juice or juice_ Also talked with Vek in the channel so it made sense with someone before posting this.



  • Entrope

    Entrope - 2009-08-16

    A bug in your client is making it (your client) display the channel name incorrectly. Your client is treating -- and displaying -- channel names as if they are encoded using some Unicode character set (probably UTF-8), even though ircu (in its 005 message) advertises its handling of channel and nick names as "rfc1459".

  • Entrope

    Entrope - 2009-08-16
    • assigned_to: nobody --> entrope
    • status: open --> closed-invalid
  • Kevin L. Mitchell

    • status: closed-invalid --> open
  • Kevin L. Mitchell

    I advised the user to open a bug report, as I don't see any reason to not remove 0xfe and 0xff from the channel name character set. Though I agree with the rest of Entrope's comments, this would appear to be a common bug, as the channel name in question appeared to be followed by two non-breaking spaces in my _terminal-based_ IRC client (owing to pass-through and UTF-8 support on the terminal, most likely).

  • Entrope

    Entrope - 2016-10-13
    • status: open --> pending
  • Entrope

    Entrope - 2016-10-13

    ISO-8859-1 and other 8-bit character sets map 0xFE and 0xFF to useful characters, so I think it is better for ircu to keep them (until/unless such time that it switches to using UTF-8).


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