mbedtls_mpi_mod_read/write: restrict pre-conditions
Require equality for the number of limbs in the modulus and the residue.
This makes these functions consistent with residue_setup().
Signed-off-by: Janos Follath <janos.follath@arm.com>
diff --git a/tests/suites/test_suite_bignum_mod.function b/tests/suites/test_suite_bignum_mod.function
index 8945968..7042ed3 100644
--- a/tests/suites/test_suite_bignum_mod.function
+++ b/tests/suites/test_suite_bignum_mod.function
@@ -148,13 +148,23 @@
TEST_EQUAL( MBEDTLS_ERR_MPI_BAD_INPUT_DATA,
mbedtls_mpi_mod_write( &rn, &m, buf->x, buf->len, endian ) );
- /* Fail for r_limbs > m->limbs */
- r.limbs = m.limbs + 1;
+ /* Fail for r_limbs < m->limbs */
+ r.limbs--;
+ TEST_ASSERT( r.limbs < m.limbs );
TEST_EQUAL( MBEDTLS_ERR_MPI_BAD_INPUT_DATA,
mbedtls_mpi_mod_read( &r, &m, buf->x, buf->len, endian ) );
TEST_EQUAL( MBEDTLS_ERR_MPI_BAD_INPUT_DATA,
mbedtls_mpi_mod_write( &r, &m, buf->x, buf->len, endian ) );
- r.limbs = r_limbs;
+ r.limbs++;
+
+ /* Fail for r_limbs > m->limbs */
+ m.limbs--;
+ TEST_ASSERT( r.limbs > m.limbs );
+ TEST_EQUAL( MBEDTLS_ERR_MPI_BAD_INPUT_DATA,
+ mbedtls_mpi_mod_read( &r, &m, buf->x, buf->len, endian ) );
+ TEST_EQUAL( MBEDTLS_ERR_MPI_BAD_INPUT_DATA,
+ mbedtls_mpi_mod_write( &r, &m, buf->x, buf->len, endian ) );
+ m.limbs++;
/* Test the read */
TEST_EQUAL( ret, mbedtls_mpi_mod_read( &r, &m, buf->x, buf->len, endian ) );
@@ -163,7 +173,9 @@
if ( r.limbs > 1 && ret == 0 )
TEST_EQUAL( MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL,
mbedtls_mpi_mod_write( &r, &m, buf->x, 1, endian ) );
+
exit:
+ mbedtls_mpi_mod_residue_release( &r );
mbedtls_mpi_mod_modulus_free( &m );
mbedtls_free( N );
mbedtls_free( R );