SSHSIG.
The signature format behind AgePony's file signing. SSHSIG lets an ordinary SSH key sign any file, and lets anyone verify it with standard OpenSSH — no PGP, no extra tooling.
SSHSIG is the signature wire format introduced in OpenSSH 8.0 that allows SSH keys to sign and verify arbitrary data, not just authenticate logins. Signatures are namespaced and produced with ssh-keygen -Y sign.
What it is
An SSHSIG signature is a small armored block beginning with -----BEGIN SSH SIGNATURE-----. It binds the signed data to the signer's public key under a namespace string — AgePony uses the namespace agepony. Verification with ssh-keygen -Y verify confirms the file was signed by the holder of a given public key and was not modified.
Why it matters
Because SSHSIG is part of OpenSSH, the entire world already has the verifier installed. You can sign a release in AgePony on your phone and a recipient on any Linux or macOS box can verify it with a one-line command, using the public key you publish. No new trust system to adopt.
Standard OpenSSH verifies an AgePony-produced signature with no extra software.
Related terms
Common questions.
Can people verify without AgePony?
Yes — any system with OpenSSH 8.0+ can verify with ssh-keygen -Y verify and your published public key.
What is the namespace for?
Namespaces stop a signature made for one purpose being replayed as another. AgePony uses agepony so its signatures are domain-separated.
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