[Mailman-Developers] What characters should be allowed in listnames

[Terri Oda]

On February 15, 2017 8:03:33 AM GMT+05:30, Mark Sapiro <mark at msapiro.net> wrote:
>On 02/14/2017 10:52 AM, Stephen J. Turnbull wrote:
>> Mark Sapiro writes:
>> 
>>  > I'd like feedback on this. What are your thoughts on what
>characters
>>  > should be allowed in list names?
>> 
>> Uh, RFC 6532 ....
>
>
>That doesn't really address my question. That has to do with
>internationalized email addresses. Granted the listname must be a valid
>local part of an email address, but that doesn't mean every valid local
>part has to be a valid list name.
>
>In particular, the issue that raises this question is a list name
>containing a slash. while 'my/list at example.com' is a legal email
>address, https://lists.example.com/mailman3/lists/my/list.example.com/
>is not a URL which will work in Postorius.
>
My gut feeling is that allowing slashes is going to lead to confusing side effects with mail clients and even potential security bugs down the road, and we should just not do it unless there's a clear need to support slashes.

But that's really just a feeling based on exploit experience, where "be conservative in what you expect" is best practice. It doesn't speak to what the standards say or what's doable.

 Terri