Vintage Cast Aluminum Camping Dutch Oven Camp Fire

I'm not exactly sure what this is. It's heavy, cast aluminum, and doesn't have a maker's mark. It measures 12"x4.25", not including the feet or cover, 5.5" with the feet, and 6.5" to the top of the rim on the cover. It has a bale handle, and t are 10 holes in the bottom, arranged in a triangle. The feet are nuts and bolts, and have surface rust. This was totally black and sooty inside when we got it, and the sides are still black, even though I scrubbed it out. I don't know if maybe you put hot coals in this to cook with or what. As you can see in the photo, the cover has a white film on it. T are no cracks, and t is no warping. If anyone has a clue what this actually is, we would love to know!