From 3361760dbb46cca2e00f053286404b5df39590b3 Mon Sep 17 00:00:00 2001 From: Trevor Gamblin Date: Tue, 5 Nov 2019 08:05:52 -0500 Subject: libgcrypt: fix CVE-2019-13627 Backport two fixes for CVE-2019-13627 from upstream to zeus. Signed-off-by: Trevor Gamblin Signed-off-by: Anuj Mittal --- ...dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch | 128 +++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 meta/recipes-support/libgcrypt/files/0001-dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch (limited to 'meta/recipes-support/libgcrypt/files/0001-dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch') diff --git a/meta/recipes-support/libgcrypt/files/0001-dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch b/meta/recipes-support/libgcrypt/files/0001-dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch new file mode 100644 index 0000000000..211e041303 --- /dev/null +++ b/meta/recipes-support/libgcrypt/files/0001-dsa-ecdsa-Fix-use-of-nonce-use-larger-one.patch @@ -0,0 +1,128 @@ +From db4e9976cc31b314aafad6626b2894e86ee44d60 Mon Sep 17 00:00:00 2001 +From: NIIBE Yutaka +Date: Thu, 8 Aug 2019 17:42:02 +0900 +Subject: [PATCH] dsa,ecdsa: Fix use of nonce, use larger one. + +Upstream-Status: Backport [https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=commit;h=db4e9976cc3] +CVE: CVE-2019-13627 +Signed-off-by: Trevor Gamblin + +* cipher/dsa-common.c (_gcry_dsa_modify_k): New. +* cipher/pubkey-internal.h (_gcry_dsa_modify_k): New. +* cipher/dsa.c (sign): Use _gcry_dsa_modify_k. +* cipher/ecc-ecdsa.c (_gcry_ecc_ecdsa_sign): Likewise. +* cipher/ecc-gost.c (_gcry_ecc_gost_sign): Likewise. + +-- + +Cherry-picked master commit of: + 7c2943309d14407b51c8166c4dcecb56a3628567 + +CVE-id: CVE-2019-13627 +GnuPG-bug-id: 4626 +Signed-off-by: NIIBE Yutaka +--- + cipher/dsa-common.c | 24 ++++++++++++++++++++++++ + cipher/dsa.c | 2 ++ + cipher/ecc-ecdsa.c | 10 +--------- + cipher/ecc-gost.c | 2 ++ + cipher/pubkey-internal.h | 1 + + 5 files changed, 30 insertions(+), 9 deletions(-) + +diff --git a/cipher/dsa-common.c b/cipher/dsa-common.c +index 8c0a6843..fe49248d 100644 +--- a/cipher/dsa-common.c ++++ b/cipher/dsa-common.c +@@ -29,6 +29,30 @@ + #include "pubkey-internal.h" + + ++/* ++ * Modify K, so that computation time difference can be small, ++ * by making K large enough. ++ * ++ * Originally, (EC)DSA computation requires k where 0 < k < q. Here, ++ * we add q (the order), to keep k in a range: q < k < 2*q (or, ++ * addming more q, to keep k in a range: 2*q < k < 3*q), so that ++ * timing difference of the EC multiply (or exponentiation) operation ++ * can be small. The result of (EC)DSA computation is same. ++ */ ++void ++_gcry_dsa_modify_k (gcry_mpi_t k, gcry_mpi_t q, int qbits) ++{ ++ gcry_mpi_t k1 = mpi_new (qbits+2); ++ ++ mpi_resize (k, (qbits+2+BITS_PER_MPI_LIMB-1) / BITS_PER_MPI_LIMB); ++ k->nlimbs = k->alloced; ++ mpi_add (k, k, q); ++ mpi_add (k1, k, q); ++ mpi_set_cond (k, k1, !mpi_test_bit (k, qbits)); ++ ++ mpi_free (k1); ++} ++ + /* + * Generate a random secret exponent K less than Q. + * Note that ECDSA uses this code also to generate D. +diff --git a/cipher/dsa.c b/cipher/dsa.c +index 22d8d782..24a53528 100644 +--- a/cipher/dsa.c ++++ b/cipher/dsa.c +@@ -635,6 +635,8 @@ sign (gcry_mpi_t r, gcry_mpi_t s, gcry_mpi_t input, DSA_secret_key *skey, + k = _gcry_dsa_gen_k (skey->q, GCRY_STRONG_RANDOM); + } + ++ _gcry_dsa_modify_k (k, skey->q, qbits); ++ + /* r = (a^k mod p) mod q */ + mpi_powm( r, skey->g, k, skey->p ); + mpi_fdiv_r( r, r, skey->q ); +diff --git a/cipher/ecc-ecdsa.c b/cipher/ecc-ecdsa.c +index 84a1cf84..97966c3a 100644 +--- a/cipher/ecc-ecdsa.c ++++ b/cipher/ecc-ecdsa.c +@@ -114,15 +114,7 @@ _gcry_ecc_ecdsa_sign (gcry_mpi_t input, ECC_secret_key *skey, + else + k = _gcry_dsa_gen_k (skey->E.n, GCRY_STRONG_RANDOM); + +- /* Originally, ECDSA computation requires k where 0 < k < n. +- * Here, we add n (the order of curve), to keep k in a +- * range: n < k < 2*n, or, addming more n, keep k in a range: +- * 2*n < k < 3*n, so that timing difference of the EC +- * multiply operation can be small. The result is same. +- */ +- mpi_add (k, k, skey->E.n); +- if (!mpi_test_bit (k, qbits)) +- mpi_add (k, k, skey->E.n); ++ _gcry_dsa_modify_k (k, skey->E.n, qbits); + + _gcry_mpi_ec_mul_point (&I, k, &skey->E.G, ctx); + if (_gcry_mpi_ec_get_affine (x, NULL, &I, ctx)) +diff --git a/cipher/ecc-gost.c b/cipher/ecc-gost.c +index a34fa084..0362a6c7 100644 +--- a/cipher/ecc-gost.c ++++ b/cipher/ecc-gost.c +@@ -94,6 +94,8 @@ _gcry_ecc_gost_sign (gcry_mpi_t input, ECC_secret_key *skey, + mpi_free (k); + k = _gcry_dsa_gen_k (skey->E.n, GCRY_STRONG_RANDOM); + ++ _gcry_dsa_modify_k (k, skey->E.n, qbits); ++ + _gcry_mpi_ec_mul_point (&I, k, &skey->E.G, ctx); + if (_gcry_mpi_ec_get_affine (x, NULL, &I, ctx)) + { +diff --git a/cipher/pubkey-internal.h b/cipher/pubkey-internal.h +index b8167c77..d31e26f3 100644 +--- a/cipher/pubkey-internal.h ++++ b/cipher/pubkey-internal.h +@@ -84,6 +84,7 @@ _gcry_rsa_pss_verify (gcry_mpi_t value, gcry_mpi_t encoded, + + + /*-- dsa-common.c --*/ ++void _gcry_dsa_modify_k (gcry_mpi_t k, gcry_mpi_t q, int qbits); + gcry_mpi_t _gcry_dsa_gen_k (gcry_mpi_t q, int security_level); + gpg_err_code_t _gcry_dsa_gen_rfc6979_k (gcry_mpi_t *r_k, + gcry_mpi_t dsa_q, gcry_mpi_t dsa_x, +-- +2.23.0 + -- cgit 1.2.3-korg