Resolves: CVE-2016-0787 - diffie_hellman_sha1: Convert bytes to bits

CVE-2016-0787.patch

@@ -0,0 +1,30 @@
+From 8a453a7b0f1e667b7369eb73b00843a8decdecc9 Mon Sep 17 00:00:00 2001
+From: Daniel Stenberg <daniel@haxx.se>
+Date: Thu, 11 Feb 2016 13:52:20 +0100
+Subject: [PATCH] diffie_hellman_sha1: convert bytes to bits
+
+As otherwise we get far too small numbers.
+
+CVE-2016-0787
+
+Signed-off-by: Kamil Dudka <kdudka@redhat.com>
+---
+ src/kex.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/src/kex.c b/src/kex.c
+index 6349457..e89b36c 100644
+--- a/src/kex.c
++++ b/src/kex.c
+@@ -133,7 +133,7 @@ static int diffie_hellman_sha1(LIBSSH2_SESSION *session,
+         memset(&exchange_state->req_state, 0, sizeof(packet_require_state_t));
+ 
+         /* Generate x and e */
+-        _libssh2_bn_rand(exchange_state->x, group_order, 0, -1);
++        _libssh2_bn_rand(exchange_state->x, group_order * 8 - 1, 0, -1);
+         _libssh2_bn_mod_exp(exchange_state->e, g, exchange_state->x, p,
+                             exchange_state->ctx);
+ 
+-- 
+2.7.0
+

libssh2.spec

@@ -12,13 +12,14 @@
 
 Name:		libssh2
 Version:	1.7.0
-Release:	1%{?dist}
+Release:	2%{?dist}
 Summary:	A library implementing the SSH2 protocol
 Group:		System Environment/Libraries
 License:	BSD
 URL:		http://www.libssh2.org/
 Source0:	http://libssh2.org/download/libssh2-%{version}.tar.gz
 Patch0:		libssh2-1.4.2-utf8.patch
+Patch2:		CVE-2016-0787.patch
 BuildRoot:	%{_tmppath}/%{name}-%{version}-%{release}-root-%(id -nu)
 BuildRequires:	coreutils
 BuildRequires:	findutils
@@ -77,6 +78,9 @@ sed -i s/4711/47%{?__isa_bits}/ tests/ssh2.{c,sh}
 # Make sure things are UTF-8...
 %patch0 -p1
 
+# diffie_hellman_sha1: Convert bytes to bits (additional fix for CVE-2016-0787)
+%patch2 -p1
+
 # Make sshd transition appropriately if building in an SELinux environment
 %if !(0%{?fedora} >= 17 || 0%{?rhel} >= 7)
 chcon $(/usr/sbin/matchpathcon -n /etc/rc.d/init.d/sshd) tests/ssh2.sh || :
@@ -154,6 +158,9 @@ rm -rf %{buildroot}
 %{_libdir}/pkgconfig/libssh2.pc
 
 %changelog
+* Wed Feb 24 2016 Kamil Dudka <kdudka@redhat.com> - 1.7.0-2
+- diffie_hellman_sha1: Convert bytes to bits (additional fix for CVE-2016-0787)
+
 * Tue Feb 23 2016 Paul Howarth <paul@city-fan.org> - 1.7.0-1
 - Update to 1.7.0
   - diffie_hellman_sha256: Convert bytes to bits (CVE-2016-0787); see