Skip redundant checks for NULL f_rng
Unless MBEDTLS_ECP_NO_INTERNAL_RNG is defined, it's no longer possible for
f_rng to be NULL at the places that randomize coordinates.
Eliminate the NULL check in this case:
- it makes it clearer to reviewers that randomization always happens (unless
the user opted out at compile time)
- a NULL check in a place where it's easy to prove the value is never NULL
might upset or confuse static analyzers (including humans)
- removing the check saves a bit of code size
Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/library/ecp.c b/library/ecp.c
index b8ce020..2dda156 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -2026,7 +2026,9 @@
i = d;
MBEDTLS_MPI_CHK( ecp_select_comb( grp, R, T, T_size, x[i] ) );
MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &R->Z, 1 ) );
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != 0 )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, R, f_rng, p_rng ) );
}
@@ -2159,7 +2161,9 @@
*
* Avoid the leak by randomizing coordinates before we normalize them.
*/
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != 0 )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_jac( grp, RR, f_rng, p_rng ) );
MBEDTLS_ECP_BUDGET( MBEDTLS_ECP_OPS_INV );
@@ -2564,7 +2568,9 @@
MOD_ADD( RP.X );
/* Randomize coordinates of the starting point */
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != NULL )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, &RP, f_rng, p_rng ) );
/* Loop invariant: R = result so far, RP = R + P */
@@ -2597,7 +2603,9 @@
*
* Avoid the leak by randomizing coordinates before we normalize them.
*/
+#if defined(MBEDTLS_ECP_NO_INTERNAL_RNG)
if( f_rng != NULL )
+#endif
MBEDTLS_MPI_CHK( ecp_randomize_mxz( grp, R, f_rng, p_rng ) );
MBEDTLS_MPI_CHK( ecp_normalize_mxz( grp, R ) );