It’s more of the latter really. The Fins never dedicated themselves to the attack on Russia in the fashion they could have. They pretty much moved into the territory they had lost as a result of the Russo-Finnish War of 1940 and stopped. On the other hand too, there was a point in time in which they may have been able to get out of the war and maintained their pre-1940 borders, but did not. This was more due to concerns over the German’s reaction to signing an armistice than it was to any desire to keep fighting the Soviets.
Finland was basically stuck between two superpowers and were influenced as a small country caught in the crossfire. Even after the war they were influenced into the sphere of the Soviets as the only superpower left in its immediate vicinity. They coined a term to describe this time of political spherical influence; Findlandization.
If I recall, the western Allies never declared war on Finland.