Change ecp_mul() prototype to allow randomization
(Also improve an error code while at it.)
diff --git a/library/ecdsa.c b/library/ecdsa.c
index 67774c9..bbdb5d5 100644
--- a/library/ecdsa.c
+++ b/library/ecdsa.c
@@ -161,9 +161,12 @@
/*
* Step 5: R = u1 G + u2 Q
+ *
+ * Since we're not using any secret data, no need to pass a RNG to
+ * ecp_mul() for countermesures.
*/
- MPI_CHK( ecp_mul( grp, &R, &u1, &grp->G ) );
- MPI_CHK( ecp_mul( grp, &P, &u2, Q ) );
+ MPI_CHK( ecp_mul( grp, &R, &u1, &grp->G, NULL, NULL ) );
+ MPI_CHK( ecp_mul( grp, &P, &u2, Q, NULL, NULL ) );
MPI_CHK( ecp_add( grp, &R, &R, &P ) );
if( ecp_is_zero( &R ) )