[vlc-devel] Playlist item options security et al

[Dennis van Amerongen]

> On Dec 24, 2007, at 7:01 PM, Rémi Denis-Courmont wrote:
> 
> > Le lundi 24 décembre 2007, Pierre d'Herbemont a écrit :
> >> On Dec 24, 2007, at 6:35 PM, Pierre d'Herbemont wrote:
> >>> What about simply lowering the m3u-extvlcopt  Error message to a
> >>> Dbg message? The freebox module is fine without extvlcopt, and
> >>> extvlcopt doesn't add much...
> >>
> >> hum... Apparently they need:
> >>
> >> #EXTVLCOPT:ts-es-id-pid
> >> #EXTVLCOPT:no-video
> >> #EXTVLCOPT:audio-track-id=1001
> >>
> >> We could simply allow certain 'safe' options, such as those, when
> >> parsing m3u.
> >
> > That's what I already stated several times. Indeed, the ASX parser
> > already does uses some playlist item options in a similar way. That
> > however would NOT work if certain insecure options (such as sout or
> > demux-dump) were needed. In this later case, a new
> > dedicated "restricted" sout option/plugin seems like the only safe
> > solution.
> 
> Yes. I have a dummy patch for that, what do you think? My concern is
> that it is a bit silly to consider to keep a list of all the safe
> options in core, whereas those are defined in the modules... Also I
> have a few concern on options parsing. But that could be a nice way to
> work around those issues.

M3U/PLS is intended for playlist and not stream/sout usage:

http://en.wikipedia.org/wiki/M3U
http://hanna.pyxidis.org/tech/m3u.html

Extended M3U:

http://forums.winamp.com/showthread.php?threadid=65772

#EXTM3U implies an extended M3U file
#EXTINF implies Extended _Information_ Field

#EXTVLCOPT is a VLC addition (is the M3U still valid?) of passing params which are not used informationally but functionally so it's debatable if the (ab)use in M3U is a valid approach for what we try to accomplish. In its current form the addition is insecure.

My vote goes to a whitelist of options as well, still maintaining backward compatibility for mainstream usage.

IsValid and valid_options_array sounds nicer to me than IsSecure and secure_options_array. Development decides what is valid and who knows what option end up being insecure after all :)

- D