Matt, keechallenge definitely works under debian via mono. With mono installed, you can follow the steps in the readme file to get keepass to load and run the plugin. You will need to create a keechallenge.dll.config file and edit it as described in the readme. You can find an alternative description here http://bubblesorted.4raab.de/content/how-run-keechallenge-keepass-plugin-yubikey-under-ubuntu-linux-mono if the readme is unclear.
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Matt, keechallenge definitely works under debian via mono. With mono installed, you can follow the steps in the readme file to get keepass to load and run the plugin. You will need to create a keechallenge.dll.config file and edit it as described in the readme. You can find an alternative description here http://bubblesorted.4raab.de/content/how-run-keechallenge-keepass-plugin-yubikey-under-ubuntu-linux-mono if the readme is unclear.