Add macro for error code addition
Adds a macro (`MBEDTLS_ERR_ADD`) to add error codes together and check that the
result will not be corrupted. This additional check is only enabled during
testing when `MBEDTLS_TEST_HOOKS` is defined.
Also includes a reference usage example in `rsa.c` where two high-level error
codes could be incorrectly added together under the right conditions. This now
ensures that when this error occurs during testing it will be correctly
reported.
Signed-off-by: Chris Jones <christopher.jones@arm.com>
diff --git a/tests/include/test/helpers.h b/tests/include/test/helpers.h
index c3a844b..1fe25d8 100644
--- a/tests/include/test/helpers.h
+++ b/tests/include/test/helpers.h
@@ -278,4 +278,14 @@
void mbedtls_test_mutex_usage_check( void );
#endif /* MBEDTLS_TEST_MUTEX_USAGE */
+#if defined(MBEDTLS_TEST_HOOKS)
+/**
+ * \brief Check that a pure high-level error code is being combined with a
+ * pure low-level error code as otherwise the resultant error code
+ * would be corrupted.
+ */
+void mbedtls_test_err_add_check( int high, int low,
+ const char *file, int line);
+#endif
+
#endif /* TEST_HELPERS_H */