Authentication with geom_eli

[Allan Fields]

On 16-Jan-08, at 2:31 PM, Ivan Voras wrote:

> Cyrus Rahman wrote:
>
>> With this in mind, the addition of a less expensive authentication
>> algorithm, say a CRC, which would provide still provide a check on  
>> the
>> channel between geom_eli and the physical disk sectors without the
>> overhead of md5 or sha256, would be extremely useful.
>
> I think this discussion was held in relation with ZFS (which by  
> default does strong hashing of ALL data ALWAYS) and that somebody  
> concluded from experiments that, given the difference in speed  
> between modern CPUs and modern drives, there wasn't much difference  
> between using CRC32 and using a strong hash.
>
> Of course, on slower / embedded devices the situation is much  
> different.

Mind you perhaps this is best implemented as a separate GEOM class  
all-together.  I have had difficulty getting the GELI SHA and MD5  
hashing to perform as expected, though it initializes with-out  
error.  Perhaps this works in a new release, I will verify, if not  
I'll file pr.

Thanks,
	Allan Fields <afields at ncf.ca>