Bignum: clean up use of enums
- Made use of enums in struct and function declaration
- All enums are handled by switch case now
- If the switch does nothing on default, omit the default case to make
compiler warnings more powerful
- The two enums are now disjoint and the value 1 is skipped to make
mistakes easier to detect
Signed-off-by: Janos Follath <janos.follath@arm.com>
diff --git a/library/bignum_mod.h b/library/bignum_mod.h
index 254a744..7950f09 100644
--- a/library/bignum_mod.h
+++ b/library/bignum_mod.h
@@ -26,6 +26,22 @@
#include "mbedtls/bignum.h"
#endif
+/* Skip 1 as it is slightly easier to accidentally pass to functions. */
+typedef enum
+{
+ MBEDTLS_MPI_MOD_REP_INVALID = 0,
+ MBEDTLS_MPI_MOD_REP_MONTGOMERY = 2,
+ MBEDTLS_MPI_MOD_REP_OPT_RED
+} mbedtls_mpi_mod_rep_selector;
+
+/* Make mbedtls_mpi_mod_rep_selector and mbedtls_mpi_mod_ext_rep disjoint to
+ * make it easier to catch when they are accidentally swapped. */
+typedef enum
+{
+ MBEDTLS_MPI_MOD_EXT_REP_INVALID = 0,
+ MBEDTLS_MPI_MOD_EXT_REP_LE = 8,
+ MBEDTLS_MPI_MOD_EXT_REP_BE
+} mbedtls_mpi_mod_ext_rep;
typedef struct
{
@@ -38,10 +54,10 @@
typedef struct {
mbedtls_mpi_uint *p;
- size_t n; // number of limbs
- size_t plen; // bitlen of p
- int ext_rep; // signals external representation (eg. byte order)
- int int_rep; // selector to signal the active member of the union
+ size_t n; // number of limbs
+ size_t plen; // bitlen of p
+ mbedtls_mpi_mod_ext_rep ext_rep; // signals external representation (eg. byte order)
+ mbedtls_mpi_mod_rep_selector int_rep; // selector to signal the active member of the union
union rep
{
mbedtls_mpi_mont_struct mont;
@@ -49,21 +65,6 @@
} rep;
} mbedtls_mpi_mod_modulus;
-typedef enum
-{
- MBEDTLS_MPI_MOD_REP_INVALID = 0,
- MBEDTLS_MPI_MOD_REP_MONTGOMERY,
- MBEDTLS_MPI_MOD_REP_OPT_RED
-} mbedtls_mpi_mod_rep_selector;
-
-typedef enum
-{
- MBEDTLS_MPI_MOD_EXT_REP_INVALID = 0,
- MBEDTLS_MPI_MOD_EXT_REP_LE,
- MBEDTLS_MPI_MOD_EXT_REP_BE
-} mbedtls_mpi_mod_ext_rep;
-
-
/** Setup a residue structure.
*
* \param r The address of residue to setup. The size is determined by \p m.
@@ -124,8 +125,8 @@
int mbedtls_mpi_mod_modulus_setup( mbedtls_mpi_mod_modulus *m,
mbedtls_mpi_uint *p,
size_t pn,
- int ext_rep,
- int int_rep );
+ mbedtls_mpi_mod_ext_rep ext_rep,
+ mbedtls_mpi_mod_rep_selector int_rep );
/** Free elements of a modulus structure.
*