yuzu-emu/mbedtls
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Use only one limb parameter for assign

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Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
This commit is contained in:
Gabor Mezei 2022-09-26 17:26:42 +02:00
parent 81e57021c6
commit 3eff425b1a
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GPG key ID: F072ACA227ACD71D
5 changed files with 14 additions and 17 deletions
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11
library/bignum_core.c
View file

@ -163,18 +163,11 @@ void mbedtls_mpi_core_bigendian_to_host( mbedtls_mpi_uint *A,
}
void mbedtls_mpi_core_cond_assign( mbedtls_mpi_uint *X,
size_t X_limbs,
const mbedtls_mpi_uint *Y,
size_t Y_limbs,
size_t limbs,
unsigned char assign )
{
/* all-bits 1 if assign is 1, all-bits 0 if assign is 0 */
mbedtls_mpi_uint limb_mask = mbedtls_ct_mpi_uint_mask( assign );
mbedtls_ct_mpi_uint_cond_assign( Y_limbs, X, Y, assign );
for( size_t i = Y_limbs; i < X_limbs; i++ )
X[i] &= ~limb_mask;
mbedtls_ct_mpi_uint_cond_assign( limbs, X, Y, assign );
}
void mbedtls_mpi_core_cond_swap( mbedtls_mpi_uint *X,

7
library/bignum_core.h
View file

@ -79,9 +79,9 @@ void mbedtls_mpi_core_bigendian_to_host( mbedtls_mpi_uint *A,
* the condition was true or not.
*
* \param[OUT] X The address of the first MPI. This must be initialized.
* \param X_limbs The number of limbs of \p X.
* It must have at least \p limbs limbs.
* \param[IN] Y The address of the second MPI. This must be initialized.
* \param Y_limbs The number of limbs of \p Y.
* \param limbs The number of limbs of \p Y.
* \param assign The condition deciding whether to perform the
* assignment or not. Must be either 0 or 1:
* * \c 1: Perform the assignment `X = Y`.
@ -95,9 +95,8 @@ void mbedtls_mpi_core_bigendian_to_host( mbedtls_mpi_uint *A,
* neither its original value nor the value in \p Y.
*/
void mbedtls_mpi_core_cond_assign( mbedtls_mpi_uint *X,
size_t X_limbs,
const mbedtls_mpi_uint *Y,
size_t Y_limbs,
size_t limbs,
unsigned char assign );
/**

3
library/bignum_mod_raw.c
View file

@ -46,8 +46,7 @@ void mbedtls_mpi_mod_raw_cond_assign( mbedtls_mpi_uint *X,
const mbedtls_mpi_mod_modulus *m,
unsigned char assign )
{
mbedtls_mpi_core_cond_assign( X, m->limbs,
Y, m->limbs, assign );
mbedtls_mpi_core_cond_assign( X, Y, m->limbs, assign );
}
void mbedtls_mpi_mod_raw_cond_swap( mbedtls_mpi_uint *X,

8
library/constant_time.c
View file

@ -682,11 +682,17 @@ int mbedtls_mpi_safe_cond_assign( mbedtls_mpi *X,
MPI_VALIDATE_RET( X != NULL );
MPI_VALIDATE_RET( Y != NULL );
/* all-bits 1 if assign is 1, all-bits 0 if assign is 0 */
mbedtls_mpi_uint limb_mask = mbedtls_ct_mpi_uint_mask( assign );
MBEDTLS_MPI_CHK( mbedtls_mpi_grow( X, Y->n ) );
X->s = mbedtls_ct_cond_select_sign( assign, Y->s, X->s );
mbedtls_mpi_core_cond_assign( X->p, X->n, Y->p, Y->n, assign );
mbedtls_mpi_core_cond_assign( X->p, Y->p, Y->n, assign );
for( size_t i = Y->n; i < X->n; i++ )
X->p[i] &= ~limb_mask;
cleanup:
return( ret );

2
tests/suites/test_suite_mpi.function
View file

@ -786,7 +786,7 @@ void mpi_core_cond_assign( data_t * input_X,
TEST_CF_SECRET( X, len_X * sizeof( mbedtls_mpi_uint ) );
TEST_CF_SECRET( Y, len_Y * sizeof( mbedtls_mpi_uint ) );
mbedtls_mpi_core_cond_assign( X, len_X, Y, len_Y, cond );
mbedtls_mpi_core_cond_assign( X, Y, len_Y, cond );
TEST_CF_PUBLIC( X, len_X * sizeof( mbedtls_mpi_uint ) );
TEST_CF_PUBLIC( Y, len_Y * sizeof( mbedtls_mpi_uint ) );