upstream: Add support for a PQC KEX/KEM:

sntrup4591761x25519-sha512@tinyssh.org using the Streamlined NTRU Prime
4591^761 implementation from SUPERCOP coupled with X25519 as a stop-loss. Not
enabled by default.

introduce KEM API; a simplified framework for DH-ish KEX methods.

from markus@ feedback & ok djm@

OpenBSD-Commit-ID: d687f76cffd3561dd73eb302d17a1c3bf321d1a7

1 files changed, 2 insertions, 1 deletions

diff --git a/sshconnect2.c b/sshconnect2.c
index 65d8be667..05657fd73 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sshconnect2.c,v 1.296 2019/01/21 01:05:00 djm Exp $ */
+/* $OpenBSD: sshconnect2.c,v 1.297 2019/01/21 10:20:12 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2008 Damien Miller.  All rights reserved.
@@ -213,6 +213,7 @@ ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
 # endif
 #endif
         ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
+        ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_kem_client;
         ssh->kex->verify_host_key=&verify_host_key_callback;
 
         ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);