forked from pool/libgcrypt
35 lines
1.2 KiB
Diff
35 lines
1.2 KiB
Diff
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From 5a22de904a0a366ae79f03ff1e13a1232a89e26b Mon Sep 17 00:00:00 2001
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From: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
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Date: Thu, 19 Jan 2017 17:00:15 +0100
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Subject: [PATCH] ecc: Store EdDSA session key in secure memory.
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* cipher/ecc-eddsa.c (_gcry_ecc_eddsa_sign): use mpi_snew to allocate
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session key.
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--
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An attacker who learns the EdDSA session key from side-channel
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observation during the signing process, can easily revover the long-
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term secret key. Storing the session key in secure memory ensures that
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constant time point operations are used in the MPI library.
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Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
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---
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cipher/ecc-eddsa.c | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/cipher/ecc-eddsa.c b/cipher/ecc-eddsa.c
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index f91f848..813e030 100644
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--- a/cipher/ecc-eddsa.c
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+++ b/cipher/ecc-eddsa.c
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@@ -603,7 +603,7 @@ _gcry_ecc_eddsa_sign (gcry_mpi_t input, ECC_secret_key *skey,
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a = mpi_snew (0);
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x = mpi_new (0);
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y = mpi_new (0);
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- r = mpi_new (0);
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+ r = mpi_snew (0);
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ctx = _gcry_mpi_ec_p_internal_new (skey->E.model, skey->E.dialect, 0,
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skey->E.p, skey->E.a, skey->E.b);
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b = (ctx->nbits+7)/8;
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--
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2.8.0.rc3
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