diff --git a/library/ecp_curves.c b/library/ecp_curves.c
index 0fa8825..9184508 100644
--- a/library/ecp_curves.c
+++ b/library/ecp_curves.c
@@ -24,6 +24,7 @@
 #include "mbedtls/ecp.h"
 #include "mbedtls/platform_util.h"
 #include "mbedtls/error.h"
+#include "mbedtls/bn_mul.h"
 
 #include "ecp_invasive.h"
 
@@ -42,45 +43,6 @@
 #define inline __inline
 #endif
 
-/*
- * Conversion macros for embedded constants:
- * build lists of mbedtls_mpi_uint's from lists of unsigned char's grouped by 8, 4 or 2
- */
-#if defined(MBEDTLS_HAVE_INT32)
-
-#define BYTES_TO_T_UINT_4( a, b, c, d )                       \
-    ( (mbedtls_mpi_uint) (a) <<  0 ) |                        \
-    ( (mbedtls_mpi_uint) (b) <<  8 ) |                        \
-    ( (mbedtls_mpi_uint) (c) << 16 ) |                        \
-    ( (mbedtls_mpi_uint) (d) << 24 )
-
-#define BYTES_TO_T_UINT_2( a, b )                   \
-    BYTES_TO_T_UINT_4( a, b, 0, 0 )
-
-#define BYTES_TO_T_UINT_8( a, b, c, d, e, f, g, h ) \
-    BYTES_TO_T_UINT_4( a, b, c, d ),                \
-    BYTES_TO_T_UINT_4( e, f, g, h )
-
-#else /* 64-bits */
-
-#define BYTES_TO_T_UINT_8( a, b, c, d, e, f, g, h ) \
-    ( (mbedtls_mpi_uint) (a) <<  0 ) |                        \
-    ( (mbedtls_mpi_uint) (b) <<  8 ) |                        \
-    ( (mbedtls_mpi_uint) (c) << 16 ) |                        \
-    ( (mbedtls_mpi_uint) (d) << 24 ) |                        \
-    ( (mbedtls_mpi_uint) (e) << 32 ) |                        \
-    ( (mbedtls_mpi_uint) (f) << 40 ) |                        \
-    ( (mbedtls_mpi_uint) (g) << 48 ) |                        \
-    ( (mbedtls_mpi_uint) (h) << 56 )
-
-#define BYTES_TO_T_UINT_4( a, b, c, d )             \
-    BYTES_TO_T_UINT_8( a, b, c, d, 0, 0, 0, 0 )
-
-#define BYTES_TO_T_UINT_2( a, b )                   \
-    BYTES_TO_T_UINT_8( a, b, 0, 0, 0, 0, 0, 0 )
-
-#endif /* bits in mbedtls_mpi_uint */
-
 #define ECP_MPI_INIT(s, n, p) {s, (n), (mbedtls_mpi_uint *)(p)}
 
 #define ECP_MPI_INIT_ARRAY(x)   \