[Swan-dev] offloading

[Andrew Cagney]

I've some pending changes that offload more crypto, but I'm left
wondering at what point is it getting out of control.

First the existing DH offload should eventually be shuffled into:

- first AUTH request fragment arrives
- offload DH part#2 in background
- when DH comes back start decrypting fragments inline

which I think is reasonable.  But then we've got:

- start unpacking packet
- offload certificate decode and verify (aka RSA - NEW)
- work on packet
- offload PAM
- work on packet
- offload AUTH proof of identity calculation (aka RSA - NEW)
- emit response
- install kernel SAs (which is the current bottle neck but I suspect
we've got O(#STATE) code)

which seems to be getting just a tad out-of-control; and I'm sure
we'll find something else.

I've looked a bit at offloading everything.  The first thing to rear
its ugly head is, of course, reorienting the connection.  ARRRRHG!