Phatbox filesystem layout

[sulaco]

By the looks of it, the phatbox sets up a ramdisk that contains most of the filesystem, including /bin /sbin /etc .......

/bin contains programs such as mount, and a path env must be set up as rc.sh doesnt specify a full path.

[AndyMan]

Looking at this site... seems like the linux environment is un-archived on the fly...  It might be old data but is probably still good


http://www.lynuxworks.com/solutions/electronics/in-action/phatnoise.php3

[AndyMan]

If only we could implement some kind of "symlink" under the vfat mounted music directory (we'd still need to mount the additional drive as well) but it may also work

[A543]

Hey AndyMan, does/can Linux automount a drive if a symlink points to it?

[sbingner]

the firmware isn't going to do anything unless the signature is correct... I expect we need to get a rom-programmer and modify the rom to not check it.... or make a mod chip similar to the xbox chip

[Oaf]

Hi everyone, I've enjoyed reading your thoughts on this.

I think there are two potential approaches:

You can either try the modchip (disabling the signature checks/making them always return true, etc)

OR

(and I think this is likely to be easier but is much less flexible) clone an existing "genuine" DMS.

I've had no time to look at this but if I were wanting to secure a drive I'd probably take some kind of hash of the unique characteristics of the drive I was "locking", e.g. manufacturer name/ID, drive serial number, BIOS version, etc (or a combination) and write it to the drive somewhere (possibly the "interesting" space before the partitions start, but who knows?) It would then be trivial for the Phatbox to read this hash, compare it with the expected value from the drive ID etc and then accept or reject...

It would be interesting to see the result of a sector copy of a DMS onto the SAME make/model/version of "normal" HD - which has had its firmware hacked to return the same serial number etc as the "genuine" DMS. HD manufacturers release flash utilities/HD toolkits, it probably wouldn't be too difficult to dump a DMS firmware (disc BIOS) image and reupload it to a non-Phatnoise drive.

I'd like to have more time to look into this but at the moment real life is getting in the way...  

If I were Phatnoise I would sell the empty DMS cases at say $50 a pop and release a signing util/development kit. It seems odd that a company should base its product on an open source solution yet take such a proprietary approach. I feel it stifles a lot of the enthusiasm for their product.

[AndyMan]

Hey AndyMan, does/can Linux automount a drive if a symlink points to it?

Nope... it doesn't auto-mount the drive unfortunately... we still need a way to mount the drive prior to referencing it

[AndyMan]

the firmware isn't going to do anything unless the signature is correct... I expect we need to get a rom-programmer and modify the rom to not check it.... or make a mod chip similar to the xbox chip

sbinger, is it the 8051 that's doing the firmware check...? if so, then I'll break out my 8051 manuals and see what I can find out.

I'm gonna buy one of those $147 specials from ebay so I don't destroy my working keg

[sbingner]

sbinger, is it the 8051 that's doing the firmware check...? if so, then I'll break out my 8051 manuals and see what I can find out.

I'm gonna buy one of those $147 specials from ebay so I don't destroy my working keg

I'm not sure what does the check... but you can look at a pic of the board itself at http://ns3.bingner.com/phatnoise/phatbox.jpg

Sam