[tor-talk] Do onion services have forward secrecy?

[Jeremy Rand]

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My understanding is that the communication between circuit hops has
forward secrecy, but I've been unable to find any documentation on
whether forward secrecy exists for traffic sent between a Tor client
and a Tor onion service (not just the forward secrecy existing between
adjacent hops).  Or, put another way -- if the machine hosting a
hidden service is compromised after data is exchanged, *and* some/all
of the Tor relays on the circuit were compromised prior to the data
being exchanged, is it feasible for the adversary to decrypt the data
being exchanged?

Some Googling didn't yield anything, other than this unanswered
StackExchange question:
https://tor.stackexchange.com/questions/760/what-is-the-reasoning-behind
- -keeping-hidden-service-onion-rsa-keys-at-1024-lengt

Cheers,
- -- 
- -Jeremy Rand
Lead Application Engineer at Namecoin
Mobile email: jeremyrandmobile at airmail.cc
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Send non-security-critical things to my Mobile with OpenPGP.
Please don't send me unencrypted messages.
My business email jeremy at veclabs.net is having technical issues at the
moment.
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