#6572 NORM Never A: Replace key with hash to reduce avahi TXT size

[Zarro Boogs per Child]

#6572: Replace key with hash to reduce avahi TXT size
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  Reporter:  morgs             |       Owner:  Collabora     
      Type:  defect            |      Status:  new           
  Priority:  normal            |   Milestone:  Never Assigned
 Component:  presence-service  |     Version:                
Resolution:                    |    Keywords:  review?       
  Verified:  0                 |    Blocking:                
 Blockedby:                    |  
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Changes (by morgs):

 * cc: Collabora, mstone, jg, cscott, marcopg (added)


Comment:

 And now for something completely different: Here is an alternative
 approach to reducing the key size in a consistent way that doesn't break
 friending: Replace the actual data in owner.key.pub - see
 6572_sugar_small_key.diff. This changes the value at profile creating time
 - first boot.

 Since PS identifies all buddies by key, the previous approach of
 substituting the key for a hash (or whatever) somewhere in the stack
 wasn't feasible as it broke the JIDs. (You calculate your own JID as a
 hash of owner.key.pub, others calculate your JID has a hash of the
 different thing you are sending out as your "key".) Fixing that required
 very intrusive changes to PS. I know that shipping the key around is
 unnecessary at this point, but since we will have a crypto design at some
 point, that's the proper time to make changes to PS.

 With this patch, there are no changes needed to PS (except that
 sync_friends never worked but I'll file that separately).

 The only other user of the key is Etoys, which (before Rainbow) used the
 key to sign projects and sandbox unsigned projects. With Rainbow on, it
 has no access to the key, and so does not sign or sandbox.

 Comments?

-- 
Ticket URL: <http://dev.laptop.org/ticket/6572#comment:12>
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