libgcrypt: Security fix CVE-2015-7511

CVE-2015-7511 libgcrypt: side-channel attack on ECDH with Weierstrass curves

affects libgcrypt < 1.6.5

adjust SRC_URI + for this version.

Patch 1 is a dependancy patch. simple macro name change.
Patch 2 is the cve fix.

(From OE-Core master rev: c691ce99bd2d249d6fdc4ad58300719488fea12c)

Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster@mvista.com>
Signed-off-by: Joshua Lock <joshua.g.lock@intel.com>

1 files changed, 55 insertions, 0 deletions

diff --git a/meta/recipes-support/libgcrypt/files/CVE-2015-7511_2.patch b/meta/recipes-support/libgcrypt/files/CVE-2015-7511_2.patch
new file mode 100644
index 0000000000..8093a18cf3
--- /dev/null
+++ b/meta/recipes-support/libgcrypt/files/CVE-2015-7511_2.patch
@@ -0,0 +1,55 @@
+From 88e1358962e902ff1cbec8d53ba3eee46407851a Mon Sep 17 00:00:00 2001
+From: NIIBE Yutaka <gniibe@fsij.org>
+Date: Wed, 25 Nov 2015 12:46:19 +0900
+Subject: [PATCH] ecc: Constant-time multiplication for Weierstrass curve.
+
+* mpi/ec.c (_gcry_mpi_ec_mul_point): Use simple left-to-right binary
+method for Weierstrass curve when SCALAR is secure.
+
+Upstream-Status: Backport
+
+http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=88e1358962e902ff1cbec8d53ba3eee46407851a
+
+CVE: CVE-2015-7511 fix
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ mpi/ec.c | 19 +++++++++++++++----
+ 1 file changed, 15 insertions(+), 4 deletions(-)
+
+Index: libgcrypt-1.6.3/mpi/ec.c
+===================================================================
+--- libgcrypt-1.6.3.orig/mpi/ec.c
++++ libgcrypt-1.6.3/mpi/ec.c
+@@ -1106,16 +1106,27 @@ _gcry_mpi_ec_mul_point (mpi_point_t resu
+   unsigned int i, loops;
+   mpi_point_struct p1, p2, p1inv;
+ 
+-  if (ctx->model == MPI_EC_EDWARDS)
++  if (ctx->model == MPI_EC_EDWARDS
++      || (ctx->model == MPI_EC_WEIERSTRASS
++          && mpi_is_secure (scalar)))
+     {
+       /* Simple left to right binary method.  GECC Algorithm 3.27 */
+       unsigned int nbits;
+       int j;
+ 
+       nbits = mpi_get_nbits (scalar);
+-      mpi_set_ui (result->x, 0);
+-      mpi_set_ui (result->y, 1);
+-      mpi_set_ui (result->z, 1);
++      if (ctx->model == MPI_EC_WEIERSTRASS)
++        {
++          mpi_set_ui (result->x, 1);
++          mpi_set_ui (result->y, 1);
++          mpi_set_ui (result->z, 0);
++        }
++      else
++        {
++          mpi_set_ui (result->x, 0);
++          mpi_set_ui (result->y, 1);
++          mpi_set_ui (result->z, 1);
++        }
+ 
+       if (mpi_is_secure (scalar))
+         {