add a new API to allow user to upload an existing certificate

[mgallien]

is needed to be able to setup sharing when an user has an existing certificate that may have been created outside of Nextcloud end-to-end encryption app

that would for example apply when an external certificate authority is in use to deliver user certificates for end-to-end encryption

[artonge]

The requirements are really that a user should be able to set its own public key? And not that an admin should be able to set a user's public key?

[mgallien]

that should be done by users as there may be situations where the user's certificate is issued by a different component from the Nextcloud server app and the user should be able to upload their certificate to enable end-to-end encrypted share feature
I would guess that we want logged-in users to be able to do it as if they were uploading just a certificate signing request (this workflow works without administrator doing something)

[artonge]

I would guess that we want logged-in users to be able to do it as if they were uploading just a certificate signing request (this workflow works without administrator doing something)

Please make sure of it. If this is true, then it looks ok :).

[mgallien]

sorry if that is unclear
yes, normal users need to be able to upload their certificate to enable sharing
now that you ask for, I think we should ensure the user certificate is valid before storing it