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Re: [patch] fixup GECOS handling

From
MSMartin Schlemmer <azarah@nosferatu.za.org>
Date
Apr 22, 2005, 16:58 UTC
Message-ID
<1114189105.29271.36.camel@nosferatu.lan>
In-Reply-To
<1114186599.31076.409.camel@axer.marchex.com>
On Fri, 2005-04-22 at 09:16 -0700, Kyle Hayes wrote:
Show 30 quoted lines
> On Fri, 2005-04-22 at 16:23 +0200, Martin Schlemmer wrote:
> > Hi,
> > 
> > This still applies - any reason for not doing this?
> 
> Seems like this will break on certain kinds of data.  See below.
> 
> >         if (!pw)
> >                 die("You don't exist. Go away!");
> >         realgecos = pw->pw_gecos;
> > +       /* The name is seperated from the room no., tel no, etc via [,;] */
> > +       if (strchr(realgecos, ','))
> > +               *strchr(realgecos, ',') = 0;
> > +       else if (strchr(realgecos, ';'))
> > +               *strchr(realgecos, ';') = 0;
> >         len = strlen(pw->pw_name);
> >         memcpy(realemail, pw->pw_name, len);
> >         realemail[len] = '@';
> 
> Suppose that the GECOS field is:
> 
> Hayes, Kyle; Room 42; 424-424-4242; foo bar baz...
> 
> You'll search for the first comma, find it, truncate my name to "Hayes",
> and continue.
> 
> I have seen this kind of GECOS in larger environments where the
> individual users are not the ones that administrate their machines.
> Using the LastName, FirstName style of name is not rare. 
> 
What OS?  With Linux at least, this is what chfn's manpage say:
----
       The only restriction placed on the contents of the fields is that no control characters may  be  present,
       nor  any  of  comma, colon, or equal sign. The other field does not have this restriction, and is used to
       store accounting information used by other applications.
----

Meaning, if they use a ',' in one of the fields (and it is a linux system with the chfn most probably from the shadow package), then they are looking for trouble. The only reason I added the ';' was because somebody said whatever OS used it instead of a ','.

Thanks,
-- 
Martin Schlemmer
Previous: Kyle HayesNext: Petr Baudis
Message 6 of 16 in “fixup GECOS handling”
  1. fixup GECOS handlingMartin Schlemmer, Apr 18, 2005
  2. David WoodhouseApr 18, 2005
  3. Martin SchlemmerApr 18, 2005
  4. fixup GECOS handlingMartin Schlemmer, Apr 22, 2005
  5. Kyle HayesApr 22, 2005
  6. Martin SchlemmerApr 22, 2005
  7. Petr BaudisApr 22, 2005
  8. Martin SchlemmerApr 22, 2005
  9. Kyle HayesApr 22, 2005
  10. Martin SchlemmerApr 22, 2005
  11. Kyle HayesApr 22, 2005
  12. Petr BaudisApr 23, 2005
  13. Martin SchlemmerApr 23, 2005
  14. Kyle HayesApr 22, 2005
  15. Andy IsaacsonApr 22, 2005
  16. Kyle HayesApr 25, 2005

Read the whole thread, see it on lore, or plain text.

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