Functions to convert raw residues to/from the modulus representation
Test cases will be generated automatically by a subsequent commit.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/library/bignum_mod_raw.h b/library/bignum_mod_raw.h
index 87e241f..dad060b 100644
--- a/library/bignum_mod_raw.h
+++ b/library/bignum_mod_raw.h
@@ -297,6 +297,40 @@
/* BEGIN MERGE SLOT 6 */
+/** Convert an MPI from canonical representation (little-endian limb array)
+ * to the representation associated with the modulus.
+ *
+ * \param[in,out] X The limb array to convert.
+ * It must have as many limbs as \p N.
+ * It is converted in place.
+ * If this function returns an error, the content of \p X
+ * is unspecified.
+ * \param[in] N The modulus structure.
+ *
+ *\ return \c 0 if successful.
+ * Otherwise an \c MBEDTLS_ERR_MPI_xxx error code.
+ */
+int mbedtls_mpi_mod_raw_canonical_to_modulus_rep(
+ mbedtls_mpi_uint *X,
+ const mbedtls_mpi_mod_modulus *N );
+
+/** Convert an MPI from the representation associated with the modulus
+ * to canonical representation (little-endian limb array).
+ *
+ * \param[in,out] X The limb array to convert.
+ * It must have as many limbs as \p N.
+ * It is converted in place.
+ * If this function returns an error, the content of \p X
+ * is unspecified.
+ * \param[in] N The modulus structure.
+ *
+ *\ return \c 0 if successful.
+ * Otherwise an \c MBEDTLS_ERR_MPI_xxx error code.
+ */
+int mbedtls_mpi_mod_raw_modulus_to_canonical_rep(
+ mbedtls_mpi_uint *X,
+ const mbedtls_mpi_mod_modulus *N );
+
/** Generate a random number uniformly in a range.
*
* This function generates a random number between \p min inclusive and