On (11/23/15 09:43), Dave Watson wrote: > Currently gcm(aes) represents ~80% of our SSL connections. > > Userspace interface: > > 1) A transform and op socket are created using the userspace crypto interface > 2) Setsockopt ALG_SET_AUTHSIZE is called > 3) Setsockopt ALG_SET_KEY is called twice, since we need both send/recv keys > 4) ALG_SET_IV cmsgs are sent twice, since we need both send/recv IVs. > To support userspace heartbeats, changeciphersuite, etc, we would also need > to get these back out, use them, then reset them via CMSG. > 5) ALG_SET_OP cmsg is overloaded to mean FD to read/write from. [from patch 0/2:] > If a non application-data TLS record is seen, it is left on the TCP > socket and an error is returned on the ALG socket, and the record is > left for userspace to manage. Interesting approach. FWIW, I was hoping to discuss solutions for securing traffic tunnelled over L3 at netdev 1.1, so hopefully we'll be able to go over the trade-offs there. I'm trying to see how your approach would fit with the RDS-type of use-case. RDS-TCP is mostly similar in concept to kcm, except that rds has its own header for multiplexing, and has no dependancy on BPF for basic things like re-assembling the datagram. If I were to try to use this for RDS-TCP, the tls_tcp_read_sock() logic would be merged into the recv_actor callback for RDS, right? Thus tls control-plane message could be seen in the middle of the data-stream, so we really have to freeze the processing of the data stream till the control-plane message is processed? I'm concerned about the possiblilites for async that can happen when we separate the data-plane from the control-plane (uspace tls does not have to deal with this), but we now have control plane separated from data-plane. (And IPsec/IKE has plenty of headaches from this sort of thing already) In the tls.c example that you have, the opfd is generated from the accept() on the AF_ALG socket- how would this work if I wanted my opfd to be a PF_RDS or a PF_KCM or similar? One concern is that this patchset provides a solution for the "80%" case but what about the other 20% (and the non x86 platforms)? E.g., if I get a cipher-suite request outside the aes-ni, what would happen (punt to uspace?) --Sowmini -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
