cuberite/polarssl
1
0
Fork 0
mirror of https://github.com/cuberite/polarssl.git synced 2025-10-31 03:30:35 -04:00
Code Issues Packages Projects Releases Wiki Activity

Simplify internal code

Browse Source 
We know that Montgomery multiplication will never be called without an
RNG, so make that clear from the beginning of the function.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
This commit is contained in:
Manuel Pégourié-Gonnard 2021-06-15 11:29:26 +02:00
parent 7962bfaa79
commit 02b5705aa3
1 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
library/ecp.c
View File

@ -2384,6 +2384,9 @@ static int ecp_mul_mxz( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
mbedtls_mpi PX;
mbedtls_ecp_point_init( &RP ); mbedtls_mpi_init( &PX );
if( f_rng == NULL )
return( MBEDTLS_ERR_ECP_BAD_INPUT_DATA );
/* Save PX and read from P before writing to R, in case P == R */
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &PX, &P->X ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &RP, P ) );
@ -2397,7 +2400,6 @@ static int ecp_mul_mxz( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
MOD_ADD( RP.X );
/* Randomize coordinates of the starting point */
if( f_rng != NULL )
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, &RP, f_rng, p_rng ) );
/* Loop invariant: R = result so far, RP = R + P */
@ -2430,9 +2432,7 @@ static int ecp_mul_mxz( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
*
* Avoid the leak by randomizing coordinates before we normalize them.
*/
if( f_rng != NULL )
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, R, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( ecp_normalize_mxz( grp, R ) );
cleanup: