They didn't allow troop movements into Norway, but did allow troops to move through from Norway, into Finland. They allowed off-duty German soldiers to travel between Norway and Germany, and sold iron ore to Germany.
They also shared intelligence with the Allied forces, helped train Danish and Norwegian troops to liberate Denmark, allowed Allied forces use of its airbases, took in a lot of Jewish refugees from Norway and Denmark, The Swedish Red Cross sent buses to evacuate concentration camp inmates, and RAoul Wallenberg used his diplomatc status to save tens of thousands of Jews in Hungary as well.