An client-side error occurs when cert commands are instructed to
write the certificate chain (--chain option) to a file
(--certificate-out option). This regression was introduced in the
'cert' plugin in commit 5a44ca6383,
and reflected in the 'ca' plugin in commit
c7064494e5.
The server behaviour did not change; rather the client did not
correctly handle the DER-encoded certificates in the
'certificate_chain' response field. Fix the issue by treating the
'certificate' field as base-64 encoded DER, and the
'certificate_chain' field as an array of raw DER certificates.
Add tests for checking that the relevant commands succeed and write
PEM data to the file (both with and without --chain).
Fixes: https://pagure.io/freeipa/issue/7700
Reviewed-By: Christian Heimes <cheimes@redhat.com>
a2ad417490