Remove redundant checks, save a few muls

ecp_mul() already checks for this, and this check is not going away, so no
need to do it twice (didn't even result in better error reporting)
This commit is contained in:
Manuel Pégourié-Gonnard 2017-08-23 17:39:18 +02:00
parent 28d162829b
commit bfa1972b4f
2 changed files with 2 additions and 12 deletions

View File

@ -87,11 +87,6 @@ static int ecdh_compute_shared_restartable( mbedtls_ecp_group *grp,
mbedtls_ecp_point_init( &P ); mbedtls_ecp_point_init( &P );
/*
* Make sure Q is a valid pubkey before using it
*/
MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, Q ) );
MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, &P, d, Q, MBEDTLS_MPI_CHK( mbedtls_ecp_mul_restartable( grp, &P, d, Q,
f_rng, p_rng, rs_ctx ) ); f_rng, p_rng, rs_ctx ) );

View File

@ -498,13 +498,6 @@ static int ecdsa_verify_restartable( mbedtls_ecp_group *grp,
goto cleanup; goto cleanup;
} }
/*
* Additional precaution: make sure Q is valid
* For ops count, group that together with step 4
*/
ECDSA_BUDGET( MBEDTLS_ECP_OPS_CHK + MBEDTLS_ECP_OPS_INV + 2 );
MBEDTLS_MPI_CHK( mbedtls_ecp_check_pubkey( grp, Q ) );
/* /*
* Step 3: derive MPI from hashed message * Step 3: derive MPI from hashed message
*/ */
@ -513,6 +506,8 @@ static int ecdsa_verify_restartable( mbedtls_ecp_group *grp,
/* /*
* Step 4: u1 = e / s mod n, u2 = r / s mod n * Step 4: u1 = e / s mod n, u2 = r / s mod n
*/ */
ECDSA_BUDGET( MBEDTLS_ECP_OPS_CHK + MBEDTLS_ECP_OPS_INV + 2 );
MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &s_inv, s, &grp->N ) ); MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &s_inv, s, &grp->N ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( pu1, &e, &s_inv ) ); MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( pu1, &e, &s_inv ) );