Use a single RSA keypair for all users and communities

[Nutomic]

Requirements

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Is your proposal related to a problem?

Lemmy currently creates and stores a separate RSA keypair for each user and each community. These keys are used to sign activities which are sent between instances. Now Soapbox had the idea to get rid of all these separate keys, and only use a single keypair for the entire instance.

This makes a lot of sense because all these keys take a lot of space, and are really not necessary. Like Soapbox, we could simply use the same keypair for every user and every community.

[dessalines]

So this would be moved to local_site then correct?

[Nutomic]

We already have a keypair for the instance actor which is stored in site table. So we can use that same keypair for all users and communities.