Adjusting #Enigmatick's previously built functions to align with the #ActivityPub #E2EE draft.

[jdt@enigmatick.social]

Adjusting #Enigmatick's previously built functions to align with the #ActivityPub #E2EE draft.

KeyPackage collection on the Actor object

Request

> curl -H "Accept: application/activity+json" https://enigmatick.social/user/jdt | jq '.keyPackages'

Response

"https://enigmatick.social/user/jdt/keys"

Retrieve the KeyPackage Collection

These are populated by the client (the browser using the wasm module loaded in the Svelte SPA). I had a different mechanism in place for managing this (using the instrument field on Activities) but am updating it to use the Add flow for the Collection as specified by the draft.

Request

> curl -H "Accept: application/activity+json" https://enigmatick.social/user/jdt/keys | jq

Response

{
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Collection",
  "id": "https://enigmatick.social/user/jdt/keys",
  "totalItems": 39,
  "next": "https://enigmatick.social/user/jdt/keys?mkp=true"
}

Follow the next link to retrieve a KeyPackage

This will mark the KeyPackage as distributed and would typically link it to the Actor that signed the request (that's temporarily disabled for testing).

Request

> curl -H "Accept: application/activity+json" https://enigmatick.social/user/jdt/keys?mkp=true | jq

Response

{
  "@context": [
    "https://www.w3.org/ns/activitystreams",
    "https://purl.archive.org/socialweb/mls"
  ],
  "type": "Collection",
  "totalItems": 1,
  "items": [
    {
      "type": "KeyPackage",
      "id": "https://enigmatick.social/key-package/cfde7b54-8d08-41e9-8eb5-d997a12e9347",
      "attributedTo": "https://enigmatick.social/user/jdt",
      "to": [
        "https://www.w3.org/ns/activitystreams#Public"
      ],
      "mediaType": "message/mls",
      "encoding": "base64",
      "content": "AAEAASCOWe7uxA8tPeI01nDP8ka2irEhgfkK2qM81/o+tEKPEiCz2h2Vv6VVuGSx/C0WINQCuazZm4rQAymxd1JdHGVvaSDurWzIE3z5eXUFz5coFGv9db7DxZDx0arb/gyRuidCAgABImh0dHBzOi8vZW5pZ21hdGljay5zb2NpYWwvdXNlci9qZHQCAAEIAAEAAgADAE0KAAEAAgADAAQABQwAAQACAAMABAAFAAcCAAEBAAAAAGeDNwsAAAAAZ/IDGwBAQJUffd/8/Efgt0ITBeMWfJYcb7S8E5U7yyUINiIUfqmsGwcvTyam6C+9F+k64NBEs0rXjGMjPA6AgiZ2oR4/1wwAQECliseeQfQb0zgq755ZiiujRqLkEWt8WOTJSsBXHK6hey6bNs4wet782NL8k92h1BNuPZDzxHaHXdXe1wgBO6QJ"
    }
  ]
}

[rimu@piefed.social]

If the private keys are stored on the instance, how is this any better than what we have now?

[jdt@enigmatick.social]

@rimu@piefed.social What makes you think it's a private key? (It's not.)

Here's some information with examples of how the keys are used and exchanged.

[jdt@enigmatick.social]

@rimu@piefed.social And no, the instance admin cannot decrypt the communications. The KeyPackage is a public key used to start an encrypted message exchange. But it cannot be used to decrypt any of the messages.

[rimu@piefed.social]

Ah I see, thanks 👍

[jdt@enigmatick.social]

@rimu@piefed.social No problem!

[silverpill@mitra.social]

@jdt

>ActivityPub E2EE draft.

Do you see any merit in that document?

Looks like boilerplate to me.

[jdt@enigmatick.social]

@silverpill@mitra.social it seems like a fair starting point to establish some common formats. There's clearly a lot of work still to be done.

There are some choices that seem questionable to me; the document seems to imply that KeyPackages as an attribute of the Actor objects can be retrieved without much control. I think that's problematic. They're only usable one time and they could easily be exhausted if distribution isn't controlled (they have to be replenished by the client and the client has to maintain all active packages in its key store).

I gate access behind a verified signature and record who is given which package at the server to establish some limits.