Add tests for invalid private parameters in ecdsa_sign()
diff --git a/tests/suites/test_suite_ecdsa.function b/tests/suites/test_suite_ecdsa.function
index ee379dc..f57ee14 100644
--- a/tests/suites/test_suite_ecdsa.function
+++ b/tests/suites/test_suite_ecdsa.function
@@ -42,7 +42,7 @@
 /* BEGIN_CASE */
 void ecdsa_prim_test_vectors( int id, char *d_str, char *xQ_str, char *yQ_str,
                               char *k_str, char *hash_str, char *r_str,
-                              char *s_str )
+                              char *s_str, int result )
 {
     ecp_group grp;
     ecp_point Q;
@@ -80,12 +80,15 @@
     }
 
     TEST_ASSERT( ecdsa_sign( &grp, &r, &s, &d, hash, hlen,
-                 rnd_buffer_rand, &rnd_info ) == 0 );
+                 rnd_buffer_rand, &rnd_info ) == result );
 
-    TEST_ASSERT( mpi_cmp_mpi( &r, &r_check ) == 0 );
-    TEST_ASSERT( mpi_cmp_mpi( &s, &s_check ) == 0 );
+    if ( result == 0 )
+    {
+        TEST_ASSERT( mpi_cmp_mpi( &r, &r_check ) == 0 );
+        TEST_ASSERT( mpi_cmp_mpi( &s, &s_check ) == 0 );
 
-    TEST_ASSERT( ecdsa_verify( &grp, hash, hlen, &Q, &r_check, &s_check ) == 0 );
+        TEST_ASSERT( ecdsa_verify( &grp, hash, hlen, &Q, &r_check, &s_check ) == 0 );
+    }
 
 exit:
     ecp_group_free( &grp );