Re: [Devil-linux-develop] remote update

[Heiko Z. <he...@zu...>]

Friedrich Lobenstock wrote:

> Heiko Zuerker wrote on 08.02.2004 20:43 MET:
> 
>> Bruce Smith wrote:
>>
>>>> I need to implement the option of remotely updating DL when it's on 
>>>> a USB stick or something.
>>>>
>>>> So far I couldn't really decide how I want to do this, so it's 
>>>> reliable and most of all secure.
>>>>
>>>> The update must be signed (pgp) and performed from within initrd, 
>>>> that's the easy part.
>>>>
>>>> My original idea was to add the iso image as boot.cd.new to the root 
>>>> of the media and then just check for it's existence, verify it, 
>>>> rename it to bootcd.iso and continue.
>>>
>>>
>>>
>>> So, the USB stick has to be large enough to hold TWO copies of the ISO?
>>
>>
>>
>> Yes correct.
>>
>>>> The major problem is that it's easy to temper with the verification 
>>>> of the signature, by replacing the initrd on the memory stick.
>>>
>>>
>>>
>>>
>>> You could put the sig on a secure location on the internet instead of on
>>> the media.  But then initrd would need the network up.  :-(
>>
>>
>>
>> That's then still the same problem, since initrd would need to verify 
>> itself,  which doesn't make much sense.
> 
> 
> Then checking a signature of the iso does not make any sense either
> if the initrd is tampered with. This seems to be a hen-and-egg problem.
> 

At least we could use it to check that the new ISO image is valid and 
there were no transfer errors.

Heiko