[tor-dev] Sanitized bridge descriptor format 1.0

[Karsten Loesing]

Hi Damian,

On 5/23/12 7:27 PM, Damian Johnson wrote:
>> The bridge descriptor tarballs contain bridge network statuses, server
>> descriptors, and extra-info descriptors.  See:
>>
>> https://metrics.torproject.org/data.html#bridgedesc
> 
> Oops, I read 'contain similar documents as the relay descriptor
> archives' as being server descriptors. Maybe in this first sentence it
> should explicitly say that it's a bundled batch of network status,
> server descriptors, and extra-info descriptors?

I tweaked the paragraph a bit.  Please feel free to edit it more and
send me a patch.

https://gitweb.torproject.org/metrics-web.git/commitdiff/3dbf9ae

>> You'll find an example here:
>>
>> https://metrics.torproject.org/formats.html#bridgedesc
>>
>> (I'll also include an example of the suggested format below.)
> 
> Oops again. Didn't figure that we'd use the same scrubbing description
> for both. Personally I'd find it more intuitive if we had separate
> sections for both, though I see why you did it this way.

It's probably a matter of taste.  Organizing the description by
descriptor type would mean we'd repeat a few things.  For example, we
replace bridge identities in all three descriptor types and IP addresses
in two of them (where the third type doesn't contain the bridge IP
address).  I think it's easier to list the changes made to all
descriptor types.

>> After thinking more about it, I came to the conclusion that we should
>> stop sanitizing *-stats lines at all.
> 
> In that case the 'router-signature' lines are the only ones being
> scrubbed out of bridge extra-info descriptors, right? If so then we
> don't need a 'router-digest' here since the digest can be calculated
> from the (now unscrubbed) content - right?

No, the extra-info descriptors contain hashed bridge fingerprints, not
the original ones.  That's why we need the "router-digest" line.

Best,
Karsten