From 2ed8fb7e4fd94fc8d3a048fe073e6724cabea4d6 Mon Sep 17 00:00:00 2001 From: Minos Galanakis Date: Wed, 14 Jun 2023 16:01:47 +0100 Subject: [PATCH] ecp_mod_raw: Enabled fast reduction. This patch modifies `mbedtls_mpi_mod_raw_mul` to utilise fast-reduction when available. Signed-off-by: Minos Galanakis --- library/bignum_mod_raw.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/library/bignum_mod_raw.c b/library/bignum_mod_raw.c index 791921151..11419f1e7 100644 --- a/library/bignum_mod_raw.c +++ b/library/bignum_mod_raw.c @@ -114,8 +114,6 @@ void mbedtls_mpi_mod_raw_sub(mbedtls_mpi_uint *X, (void) mbedtls_mpi_core_add_if(X, N->p, N->limbs, (unsigned) c); } -#if defined(MBEDTLS_TEST_HOOKS) - MBEDTLS_STATIC_TESTABLE void mbedtls_mpi_mod_raw_fix_quasi_reduction(mbedtls_mpi_uint *X, const mbedtls_mpi_mod_modulus *N) @@ -125,7 +123,6 @@ void mbedtls_mpi_mod_raw_fix_quasi_reduction(mbedtls_mpi_uint *X, (void) mbedtls_mpi_core_add_if(X, N->p, N->limbs, (unsigned) c); } -#endif /* MBEDTLS_TEST_HOOKS */ void mbedtls_mpi_mod_raw_mul(mbedtls_mpi_uint *X, const mbedtls_mpi_uint *A, @@ -133,8 +130,22 @@ void mbedtls_mpi_mod_raw_mul(mbedtls_mpi_uint *X, const mbedtls_mpi_mod_modulus *N, mbedtls_mpi_uint *T) { - mbedtls_mpi_core_montmul(X, A, B, N->limbs, N->p, N->limbs, - N->rep.mont.mm, T); + const size_t T_limbs = (N->limbs * 2); + switch (N->int_rep) { + case MBEDTLS_MPI_MOD_REP_MONTGOMERY: + mbedtls_mpi_core_montmul(X, A, B, N->limbs, N->p, N->limbs, + N->rep.mont.mm, T); + break; + case MBEDTLS_MPI_MOD_REP_OPT_RED: + mbedtls_mpi_core_mul(T, A, N->limbs, B, N->limbs); + (*N->rep.ored.modp)(T, T_limbs); + mbedtls_mpi_mod_raw_fix_quasi_reduction(T, N); + memcpy(X, T, N->limbs * sizeof(mbedtls_mpi_uint)); + break; + default: + break; + } + } size_t mbedtls_mpi_mod_raw_inv_prime_working_limbs(size_t AN_limbs)