diff options
| author | djm@openbsd.org <djm@openbsd.org> | 2015-03-26 07:00:04 +0000 |
|---|---|---|
| committer | Damien Miller <djm@mindrot.org> | 2015-03-27 12:02:27 +1100 |
| commit | f9b78852379b74a2d14e6fc94fe52af30b7e9c31 (patch) | |
| tree | 8e6c292cf61656a0be2f744be2155956f0142fbf /kexc25519.c | |
| parent | b8afbe2c1aaf573565e4da775261dfafc8b1ba9c (diff) | |
| download | openssh-git-f9b78852379b74a2d14e6fc94fe52af30b7e9c31.tar.gz | |
upstream commit
ban all-zero curve25519 keys as recommended by latest
CFRG curves draft; ok markus
Diffstat (limited to 'kexc25519.c')
| -rw-r--r-- | kexc25519.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/kexc25519.c b/kexc25519.c index b6e6c401..8d8cd4a2 100644 --- a/kexc25519.c +++ b/kexc25519.c @@ -1,4 +1,4 @@ -/* $OpenBSD: kexc25519.c,v 1.8 2015/01/19 20:16:15 markus Exp $ */ +/* $OpenBSD: kexc25519.c,v 1.9 2015/03/26 07:00:04 djm Exp $ */ /* * Copyright (c) 2001, 2013 Markus Friedl. All rights reserved. * Copyright (c) 2010 Damien Miller. All rights reserved. @@ -66,6 +66,11 @@ kexc25519_shared_key(const u_char key[CURVE25519_SIZE], u_char shared_key[CURVE25519_SIZE]; int r; + /* Check for all-zero public key */ + explicit_bzero(shared_key, CURVE25519_SIZE); + if (timingsafe_bcmp(pub, shared_key, CURVE25519_SIZE) == 0) + return SSH_ERR_KEY_INVALID_EC_VALUE; + crypto_scalarmult_curve25519(shared_key, key, pub); #ifdef DEBUG_KEXECDH dump_digest("shared secret", shared_key, CURVE25519_SIZE); |