eap: Introduce state reset

This is meant to reset the EAP state back to its original state without
affecting any state variables obtained through load_settings.  This can
be useful for EAP Reauthentication triggered by the AP.

src/eap.c

@@ -93,6 +93,20 @@ void eap_set_event_func(struct eap_state *eap, eap_event_func_t func)
 	eap->event_func = func;
 }
 
+bool eap_reset(struct eap_state *eap)
+{
+	if (eap->method_state && eap->method->reset_state) {
+		if (!eap->method->reset_state(eap))
+			return false;
+	}
+
+	eap->method_success = false;
+	l_timeout_remove(eap->complete_timeout);
+	eap->complete_timeout = NULL;
+
+	return true;
+}
+
 void eap_free(struct eap_state *eap)
 {
 	if (eap->method_state && eap->method->free)

src/eap.h

@@ -70,6 +70,7 @@ int eap_check_settings(struct l_settings *settings, struct l_queue *secrets,
 			struct l_queue **out_missing);
 bool eap_load_settings(struct eap_state *eap, struct l_settings *settings,
 			const char *prefix);
+bool eap_reset(struct eap_state *eap);
 
 void eap_set_key_material_func(struct eap_state *eap,
 				eap_key_material_func_t func);
@@ -130,6 +131,9 @@ struct eap_method {
 	bool (*load_settings)(struct eap_state *eap,
 				struct l_settings *settings,
 				const char *prefix);
+
+	/* Reset the internal state back to initial conditions */
+	bool (*reset_state)(struct eap_state *eap);
 	void (*free)(struct eap_state *eap);
 
 	void (*handle_request)(struct eap_state *eap,