Re: What operations in store_parsed_open() need the privilege?

[Thomas Bushnell BSG]

On Thu, 2008-08-28 at 00:21 +0200, Da Zheng wrote:
> Thomas Bushnell BSG wrote:
> > On Wed, 2008-08-27 at 23:32 +0200, Da Zheng wrote:
> >   
> >> I know boot fails and gets EPERM when it calls store_parsed_open, but I 
> >> need to know what operations inside store_parsed_open() fail. Otherwise, 
> >> I don't know how to fix it.
> >>     
> >
> > Boot assumes that it is run as root, and assumes that quite thoroughly.
> >   
> It's exactly my task, to make every user able to run their own subhurd.

Right.  You'll have to do more than fix up your servers to deal with the
non-root situation (as you know, proc will require careful work).  But
also boot will require significant work.

> > You need to have boot simply not even *try* to open such a device.  Note
> > that boot isn't calling your servers at all.  It calls the ones of its
> > containing environment.
> >
> > I assume that store_parsed_open fails because it doesn't have
> > permissions on the underlying /dev node.
> >   
> yes. but to be specific, it really depends on how we run boot.
> If we run "boot -T device servers.boot hd1", what store_parsed_open does 
> is to open the device by calling get_privileged_ports() and device_open().
> In this case, there is nothing to do with /dev nodes, and my proc proxy 
> might be able to give a help:-)

The question you must think carefully about is which functions are
called by boot, and thus run in the context of the parent Hurd.  

Thomas