diff --git a/tests/suites/test_suite_ecdsa.function b/tests/suites/test_suite_ecdsa.function
index 22d92b6df..0e7283bc7 100644
--- a/tests/suites/test_suite_ecdsa.function
+++ b/tests/suites/test_suite_ecdsa.function
@@ -74,6 +74,31 @@ void ecdsa_invalid_param( )
                        mbedtls_ecdsa_sign_det( &grp, &m, &m, &m,
                                                 NULL, sizeof( buf ),
                                                 valid_md ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
+                       mbedtls_ecdsa_sign_det_ext( NULL, &m, &m, &m,
+                                                   buf, sizeof( buf ),
+                                                   valid_md,
+                                                   rnd_std_rand, NULL ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
+                       mbedtls_ecdsa_sign_det_ext( &grp, NULL, &m, &m,
+                                                   buf, sizeof( buf ),
+                                                   valid_md,
+                                                   rnd_std_rand, NULL ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
+                       mbedtls_ecdsa_sign_det_ext( &grp, &m, NULL, &m,
+                                                   buf, sizeof( buf ),
+                                                   valid_md,
+                                                   rnd_std_rand, NULL ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
+                       mbedtls_ecdsa_sign_det_ext( &grp, &m, &m, NULL,
+                                                   buf, sizeof( buf ),
+                                                   valid_md,
+                                                   rnd_std_rand, NULL ) );
+    TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
+                       mbedtls_ecdsa_sign_det_ext( &grp, &m, &m, &m,
+                                                   NULL, sizeof( buf ),
+                                                   valid_md,
+                                                   rnd_std_rand, NULL ) );
 #endif /* MBEDTLS_ECDSA_DETERMINISTIC */
 
     TEST_INVALID_PARAM_RET( MBEDTLS_ERR_ECP_BAD_INPUT_DATA,
@@ -330,6 +355,16 @@ void ecdsa_det_test_vectors( int id, char * d_str, int md_alg, char * msg,
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &r, &r_check ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &s, &s_check ) == 0 );
 
+    mbedtls_mpi_free( &r ); mbedtls_mpi_free( &s );
+    mbedtls_mpi_init( &r ); mbedtls_mpi_init( &s );
+
+    TEST_ASSERT(
+                mbedtls_ecdsa_sign_det_ext( &grp, &r, &s, &d, hash, hlen,
+                                            md_alg, rnd_std_rand, NULL )
+                == 0 );
+
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &r, &r_check ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &s, &s_check ) == 0 );
 exit:
     mbedtls_ecp_group_free( &grp );
     mbedtls_mpi_free( &d ); mbedtls_mpi_free( &r ); mbedtls_mpi_free( &s );