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In reply to It's Now Possible To Sign Arbitrary Data With Your SSH Keys

Reader Charlie on 2021-11-12 at 18:45:

You can actually use openssl with RSA keys generated by ssh-keygen to sign also, and this has worked for a long time.

You will have to generate an openssl-compatible public key:

openssl rsa -in ~/.ssh/id_rsa -pubout -out ~/.ssh/

To sign:

openssl dgst -sha256 -sign ~/.ssh/id_rsa -out known_hosts.sha256 known_hosts

To verify:

openssl dgst -sha256 -verify ~/.ssh/ -signature known_hosts.sha256 known_hosts


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