upstream: save the derived session id in kex_derive_keys() rather

than making each kex method implementation do it.

from markus@ ok djm@

OpenBSD-Commit-ID: d61ade9c8d1e13f665f8663c552abff8c8a30673

1 files changed, 9 insertions, 1 deletions

diff --git a/kex.c b/kex.c
index 30e1c261d..0d5618ecc 100644
--- a/kex.c
+++ b/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.143 2018/12/27 03:25:25 djm Exp $ */
+/* $OpenBSD: kex.c,v 1.144 2019/01/21 09:55:52 djm Exp $ */
 /*
  * Copyright (c) 2000, 2001 Markus Friedl.  All rights reserved.
  *
@@ -1009,6 +1009,14 @@ kex_derive_keys(struct ssh *ssh, u_char *hash, u_int hashlen,
         u_int i, j, mode, ctos;
         int r;
 
+        /* save initial hash as session id */
+        if (kex->session_id == NULL) {
+                kex->session_id_len = hashlen;
+                kex->session_id = malloc(kex->session_id_len);
+                if (kex->session_id == NULL)
+                        return SSH_ERR_ALLOC_FAIL;
+                memcpy(kex->session_id, hash, kex->session_id_len);
+        }
         for (i = 0; i < NKEYS; i++) {
                 if ((r = derive_key(ssh, 'A'+i, kex->we_need, hash, hashlen,
                     shared_secret, &keys[i])) != 0) {