Rm ecp_add() and add ecp_muladd()
diff --git a/library/ecdsa.c b/library/ecdsa.c
index a7dcddb..babc588 100644
--- a/library/ecdsa.c
+++ b/library/ecdsa.c
@@ -203,9 +203,9 @@
{
int ret;
mbedtls_mpi e, s_inv, u1, u2;
- mbedtls_ecp_point R, P;
+ mbedtls_ecp_point R;
- mbedtls_ecp_point_init( &R ); mbedtls_ecp_point_init( &P );
+ mbedtls_ecp_point_init( &R );
mbedtls_mpi_init( &e ); mbedtls_mpi_init( &s_inv ); mbedtls_mpi_init( &u1 ); mbedtls_mpi_init( &u2 );
/* Fail cleanly on curves such as Curve25519 that can't be used for ECDSA */
@@ -249,9 +249,7 @@
* Since we're not using any secret data, no need to pass a RNG to
* mbedtls_ecp_mul() for countermesures.
*/
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, &R, &u1, &grp->G, NULL, NULL ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, &P, &u2, Q, NULL, NULL ) );
- MBEDTLS_MPI_CHK( mbedtls_ecp_add( grp, &R, &R, &P ) );
+ MBEDTLS_MPI_CHK( mbedtls_ecp_muladd( grp, &R, &u1, &grp->G, &u2, Q ) );
if( mbedtls_ecp_is_zero( &R ) )
{
@@ -275,7 +273,7 @@
}
cleanup:
- mbedtls_ecp_point_free( &R ); mbedtls_ecp_point_free( &P );
+ mbedtls_ecp_point_free( &R );
mbedtls_mpi_free( &e ); mbedtls_mpi_free( &s_inv ); mbedtls_mpi_free( &u1 ); mbedtls_mpi_free( &u2 );
return( ret );
diff --git a/library/ecp.c b/library/ecp.c
index f0fcc1f..52cedd3 100644
--- a/library/ecp.c
+++ b/library/ecp.c
@@ -1049,24 +1049,6 @@
}
/*
- * Addition: R = P + Q, result's coordinates normalized
- */
-int mbedtls_ecp_add( const mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
- const mbedtls_ecp_point *P, const mbedtls_ecp_point *Q )
-{
- int ret;
-
- if( ecp_get_type( grp ) != ECP_TYPE_SHORT_WEIERSTRASS )
- return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
-
- MBEDTLS_MPI_CHK( ecp_add_mixed( grp, R, P, Q ) );
- MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, R ) );
-
-cleanup:
- return( ret );
-}
-
-/*
* Randomize jacobian coordinates:
* (X, Y, Z) -> (l^2 X, l^3 Y, l Z) for random l
* This is sort of the reverse operation of ecp_normalize_jac().
@@ -1684,6 +1666,32 @@
}
#endif /* ECP_SHORTWEIERSTRASS */
+/*
+ * Linear combination
+ */
+int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
+ const mbedtls_mpi *m, const mbedtls_ecp_point *P,
+ const mbedtls_mpi *n, const mbedtls_ecp_point *Q )
+{
+ int ret;
+ mbedtls_ecp_point mP;
+
+ if( ecp_get_type( grp ) != ECP_TYPE_SHORT_WEIERSTRASS )
+ return( MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE );
+
+ mbedtls_ecp_point_init( &mP );
+
+ MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, &mP, m, P, NULL, NULL ) );
+ MBEDTLS_MPI_CHK( mbedtls_ecp_mul( grp, R, n, Q, NULL, NULL ) );
+ MBEDTLS_MPI_CHK( ecp_add_mixed( grp, R, &mP, R ) );
+ MBEDTLS_MPI_CHK( ecp_normalize_jac( grp, R ) );
+
+cleanup:
+ mbedtls_ecp_point_free( &mP );
+
+ return( ret );
+}
+
#if defined(ECP_MONTGOMERY)
/*