OpenSSH certificates (for Unix auth)

OpenSSH certificates are single lines of text consisting of three components, separated by spaces:

<certtype> <space> <base64cert> <space> <pubkeyfilename>

Sample OpenSSH certificate

ecdsa-sha2-nistp256-cert-v01@openssh.com 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 id_ecdsa.pub

(The complete certificate appears on a single line of text)