diff --git a/library/bignum_mod_raw.c b/library/bignum_mod_raw.c
index 2f49ea2..22e56b7 100644
--- a/library/bignum_mod_raw.c
+++ b/library/bignum_mod_raw.c
@@ -52,11 +52,12 @@
 int mbedtls_mpi_mod_raw_read( mbedtls_mpi_uint *X,
                               const mbedtls_mpi_mod_modulus *m,
                               const unsigned char *input,
-                              size_t input_length )
+                              size_t input_length,
+                              mbedtls_mpi_mod_ext_rep ext_rep )
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
-    switch( m->ext_rep )
+    switch( ext_rep )
     {
         case MBEDTLS_MPI_MOD_EXT_REP_LE:
             ret = mbedtls_mpi_core_read_le( X, m->limbs,
@@ -87,9 +88,10 @@
 int mbedtls_mpi_mod_raw_write( const mbedtls_mpi_uint *A,
                                const mbedtls_mpi_mod_modulus *m,
                                unsigned char *output,
-                               size_t output_length )
+                               size_t output_length,
+                               mbedtls_mpi_mod_ext_rep ext_rep )
 {
-    switch( m->ext_rep )
+    switch( ext_rep )
     {
         case MBEDTLS_MPI_MOD_EXT_REP_LE:
             return( mbedtls_mpi_core_write_le( A, m->limbs,