| Brad Bishop | 37a0e4d | 2017-12-04 01:01:44 -0500 | [diff] [blame^] | 1 | CVE: CVE-2017-9526 |
| 2 | Upstream-Status: Backport |
| 3 | Signed-off-by: Ross Burton <ross.burton@intel.com> |
| 4 | |
| 5 | From b3cab278eb9c2ceda79f980bc26460d97f260041 Mon Sep 17 00:00:00 2001 |
| 6 | From: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be> |
| 7 | Date: Thu, 19 Jan 2017 17:00:15 +0100 |
| 8 | Subject: [PATCH] ecc: Store EdDSA session key in secure memory. |
| 9 | |
| 10 | * cipher/ecc-eddsa.c (_gcry_ecc_eddsa_sign): use mpi_snew to allocate |
| 11 | session key. |
| 12 | -- |
| 13 | |
| 14 | An attacker who learns the EdDSA session key from side-channel |
| 15 | observation during the signing process, can easily revover the long- |
| 16 | term secret key. Storing the session key in secure memory ensures that |
| 17 | constant time point operations are used in the MPI library. |
| 18 | |
| 19 | Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be> |
| 20 | --- |
| 21 | cipher/ecc-eddsa.c | 2 +- |
| 22 | 1 file changed, 1 insertion(+), 1 deletion(-) |
| 23 | |
| 24 | diff --git a/cipher/ecc-eddsa.c b/cipher/ecc-eddsa.c |
| 25 | index f91f8489..813e030d 100644 |
| 26 | --- a/cipher/ecc-eddsa.c |
| 27 | +++ b/cipher/ecc-eddsa.c |
| 28 | @@ -603,7 +603,7 @@ _gcry_ecc_eddsa_sign (gcry_mpi_t input, ECC_secret_key *skey, |
| 29 | a = mpi_snew (0); |
| 30 | x = mpi_new (0); |
| 31 | y = mpi_new (0); |
| 32 | - r = mpi_new (0); |
| 33 | + r = mpi_snew (0); |
| 34 | ctx = _gcry_mpi_ec_p_internal_new (skey->E.model, skey->E.dialect, 0, |
| 35 | skey->E.p, skey->E.a, skey->E.b); |
| 36 | b = (ctx->nbits+7)/8; |
| 37 | -- |
| 38 | 2.11.0 |
| 39 | |