I've looked around the site but found no mention of these for the download files. Aren't there any available? I'd feel better if I had those.
The content of this topic has been archived on 10 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.
There are SHA256 checksums on each download folder; for example:
https://downloads.openwrt.org/releases/ … 21xx/nand/
The discussion might have continued from here.