[X2Go-Dev] [X2go-User] Usernames with dashes causes errors?

[newsgroups.mail2 at stefanbaur.de]

Am 21.02.2012 16:40, schrieb Mike Gabriel:
> I just took a look at this and it is not so trivial to fix...
>
> Debian's adduser (3.110) script checks validity of user names against 
> this regexp:
>
>   '/^[_.A-Za-z0-9][- at _.A-Za-z0-9]*$?$/'
>
> Using a '-' as a field separator in the session ID intereferes with 
> the allowed characters in usernames.
>
> The issue has to be addressed in x2goserver, x2goclient and 
> python-x2go. I am not sure about the other helper applications (like 
> the desktop bindings, desktopsharing, etc.).

Nasty bash hacker approach:
1) "#" isn't allowed, so it would work as a separator instead of the dash
2) To avoid confusion when server and client aren't using the same 
version, prefix the string with "#" when it's the new version where all 
dashes are replaced with "#"
3) in x2goclient, *only* replace the dashes when you detect that the 
username does in fact contain a dash - that way, a new client can talk 
to an old server (unless the username contains a dash, in which case it 
would break - but that's what happens with an old client and old server 
as well, so nothing gained, but also nothing lost)

Variant: Only apply the substitution to the user name field, i.e.:
myusername-remaining-parts-of-string -> myusername-remaining-parts-of-string
my-user-name-remaining-parts-of-string 
->#my#user#name-remaining-parts-of-string

(Of course, if "#" causes trouble, too, substitute another character 
that isn't allowed by the above regex.)

-Stefan