AuroraMiddleware/mbedtls
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Stop checking for argument change

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This was intended to detect aborted operations, but now that case is handled
by the caller freeing the restart context.

Also, as the internal sub-context is managed by the callee, no need for the
caller to free/reset the restart context between successful calls.
This commit is contained in:
Manuel Pégourié-Gonnard 2017-04-20 09:47:06 +02:00
parent 3cade22f96
commit 8467e6848d
3 changed files with 6 additions and 29 deletions
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14
include/mbedtls/ecp.h
View File

@ -263,9 +263,10 @@ typedef struct
*
* If more operations are needed to complete a computation,
* MBEDTLS_ERR_ECP_IN_PROGRESS will be returned by the
* function performing the computation. That function will
* then need to be called again with the same arguments until
* it returns 0 or an other error code.
* function performing the computation. It is then the
* caller's responsibility to either call again with the same
* arguments until it returns 0 or an error code; or to free
* the restart context if the operation is to be aborted.
*
* This only affects functions that accept a pointer to a
* \c mbedtls_ecp_restart_ctx as an argument, and only works
@ -615,14 +616,11 @@ int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
* \param P Point to multiply
* \param f_rng RNG function (see notes)
* \param p_rng RNG parameter
* \param rs_ctx Restart context - must be non-NULL to enable early-return
* \param rs_ctx Restart context
*
* \return See \c mbedtls_ecp_mul(), or
* MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
* operations was reached (see \c mbedtls_ecp_set_max_ops()),
* indicating the function should be called again with the
* exact same arguments.
*
* operations was reached: see \c mbedtls_ecp_set_max_ops().
*/
int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
const mbedtls_mpi *m, const mbedtls_ecp_point *P,

18
library/ecp.c
View File

@ -105,8 +105,6 @@ void mbedtls_ecp_set_max_ops( unsigned max_ops )
*/
struct mbedtls_ecp_restart_mul {
unsigned ops_done; /* number of operations done this time */
mbedtls_mpi m; /* saved argument: scalar */
mbedtls_ecp_point P; /* saved argument: point */
mbedtls_ecp_point R; /* current intermediate result */
size_t i; /* current index in various loops, 0 outside */
mbedtls_ecp_point *T; /* table for precomputed points */
@ -139,8 +137,6 @@ static void ecp_restart_mul_free( mbedtls_ecp_restart_mul_ctx *ctx )
if( ctx == NULL )
return;
mbedtls_mpi_free( &ctx->m );
mbedtls_ecp_point_free( &ctx->P );
mbedtls_ecp_point_free( &ctx->R );
if( ctx->T != NULL ) {
@ -1763,17 +1759,6 @@ static int ecp_mul_comb( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
#endif
#if defined(MBEDTLS_ECP_EARLY_RETURN)
/* check for restart with new arguments */
if( rs_ctx != NULL && rs_ctx->rsm != NULL && rs_ctx->rsm != NULL &&
( mbedtls_mpi_cmp_mpi( m, &rs_ctx->rsm->m ) != 0 ||
mbedtls_mpi_cmp_mpi( &P->X, &rs_ctx->rsm->P.X ) != 0 ||
mbedtls_mpi_cmp_mpi( &P->Y, &rs_ctx->rsm->P.Y ) != 0 ) )
{
ecp_restart_mul_free( rs_ctx->rsm );
mbedtls_free( rs_ctx->rsm );
rs_ctx->rsm = NULL;
}
/* set up restart context if needed */
if( ecp_max_ops != 0 && rs_ctx != NULL && rs_ctx->rsm == NULL )
{
@ -1782,9 +1767,6 @@ static int ecp_mul_comb( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
return( MBEDTLS_ERR_ECP_ALLOC_FAILED );
ecp_restart_mul_init( rs_ctx->rsm );
MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &rs_ctx->rsm->m, m ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_copy( &rs_ctx->rsm->P, P ) );
}
/* reset ops count for this call */

3
tests/suites/test_suite_ecp.function
View File

@ -116,9 +116,6 @@ void ecp_test_vect_restart( int id,
TEST_ASSERT( cnt_restarts >= min_restarts );
TEST_ASSERT( cnt_restarts <= max_restarts );
/* Prepare context for new operation */
mbedtls_ecp_restart_free( &ctx );
/* Non-base point case */
cnt_restarts = 0;
do {