Re: username above 13 characters not accepted

[Thorsten Kukuk <kukuk suse de>]

On Sat, May 05, Chris Siakos wrote:

> Hello Steve,
> 
> There are no custom libraries.  The account information is stored in a mysql
> database.
> Is there someone I cant contact that cant reproduce it on SuSE, or any
> relevant mailing lists?  What SuSE version are they using.
> 
> I also noticed that a password longer than 13 characters is accepted OK.
> Its only username dependant.

This all has nothing to do with PAM. If you would look at the source
code of the daemons you are using:

[...]

static char curname[16];        /* current USER name */

[...]

                strncpy(curname, name, sizeof(curname)-1);
                curname[sizeof(curname)-1] = '\0';


[...]
                if (pam_start ("ftp", curname, &conv, &pamh) != PAM_SUCCESS)
                        goto pam_fail;


Some applications have a limit of 16 byte for the username. This has 
nothing to do with PAM, if PAM does not get more than 15 characters,
it cannot find the username.
If it works sometimes for you: Maybe the daemons have it implemented
different, depending if they use PAM or not, or some daemons overwrite
memory, or something else.

  Thorsten

-- 
Thorsten Kukuk       http://www.suse.de/~kukuk/        kukuk@suse.de
SuSE GmbH            Schanzaeckerstr. 10             90443 Nuernberg
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