summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authordtucker <dtucker>2013-10-09 23:32:39 +0000
committerdtucker <dtucker>2013-10-09 23:32:39 +0000
commitab3e6632dd18a952545785d2c62e9e606cf85549 (patch)
treedeee58a116cc47592f802814d3c8cffd3591d957
parentd64169e1bb4374a7d9d24e68d182a7e6f5f747b9 (diff)
downloadopenssh-ab3e6632dd18a952545785d2c62e9e606cf85549.tar.gz
- dtucker@cvs.openbsd.org 2013/10/08 11:42:13
[dh.c dh.h] Increase the size of the Diffie-Hellman groups requested for a each symmetric key size. New values from NIST Special Publication 800-57 with the upper limit specified by RFC4419. Pointed out by Peter Backes, ok djm@.
-rw-r--r--ChangeLog6
-rw-r--r--dh.c17
-rw-r--r--dh.h3
3 files changed, 18 insertions, 8 deletions
diff --git a/ChangeLog b/ChangeLog
index 6152abb5..5eb73c9f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,6 +21,12 @@
[sshconnect.c]
bz#1211: make BindAddress work with UsePrivilegedPort=yes; patch from
swp AT swp.pp.ru; ok dtucker@
+ - dtucker@cvs.openbsd.org 2013/10/08 11:42:13
+ [dh.c dh.h]
+ Increase the size of the Diffie-Hellman groups requested for a each
+ symmetric key size. New values from NIST Special Publication 800-57 with
+ the upper limit specified by RFC4419. Pointed out by Peter Backes, ok
+ djm@.
20131009
- (djm) [openbsd-compat/arc4random.c openbsd-compat/chacha_private.h] Pull
diff --git a/dh.c b/dh.c
index 449dd385..d33af1fa 100644
--- a/dh.c
+++ b/dh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: dh.c,v 1.51 2013/07/02 12:31:43 markus Exp $ */
+/* $OpenBSD: dh.c,v 1.52 2013/10/08 11:42:13 dtucker Exp $ */
/*
* Copyright (c) 2000 Niels Provos. All rights reserved.
*
@@ -352,17 +352,20 @@ dh_new_group14(void)
/*
* Estimates the group order for a Diffie-Hellman group that has an
- * attack complexity approximately the same as O(2**bits). Estimate
- * with: O(exp(1.9223 * (ln q)^(1/3) (ln ln q)^(2/3)))
+ * attack complexity approximately the same as O(2**bits).
+ * Values from NIST Special Publication 800-57: Recommendation for Key
+ * Management Part 1 (rev 3) limited by the recommended maximum value
+ * from RFC4419 section 3.
*/
int
dh_estimate(int bits)
{
-
+ if (bits <= 112)
+ return 2048;
if (bits <= 128)
- return (1024); /* O(2**86) */
+ return 3072;
if (bits <= 192)
- return (2048); /* O(2**116) */
- return (4096); /* O(2**156) */
+ return 7680;
+ return 8192;
}
diff --git a/dh.h b/dh.h
index dfc1480e..48f7b68e 100644
--- a/dh.h
+++ b/dh.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: dh.h,v 1.10 2008/06/26 09:19:40 djm Exp $ */
+/* $OpenBSD: dh.h,v 1.11 2013/10/08 11:42:13 dtucker Exp $ */
/*
* Copyright (c) 2000 Niels Provos. All rights reserved.
@@ -43,6 +43,7 @@ int dh_pub_is_valid(DH *, BIGNUM *);
int dh_estimate(int);
+/* Min and max values from RFC4419. */
#define DH_GRP_MIN 1024
#define DH_GRP_MAX 8192