I did a thorough security review of my FEP-ae97 implementation, and hardened the server side to prevent potential impersonation of other actors on the same server by malicious clients.
As of version 4.2.1, everything is working again, including cloned accounts (latest fep-ae97-client is required).
FEP-ae97 security audit: https://codeberg.org/fediverse/fep/pulls/595
I added a new section, "Security considerations", and a new requirement: compatible identifiers of server-generated keys MUST have the server's origin. Here's how that looks in practice:
This FEP update goes together with two others:
- FEP-2277: ActivityPub core types - The VerificationMethod class has the highest priority now, because servers must be able to identify a verification method even if it has other class-defining properties (e.g. href).
- FEP-fe34: Origin-based security model - clarifying the base assumptions of the model
Published the code of my tiny FEP-ae97 server:
https://codeberg.org/silverpill/fep-ae97-server
I used this project to test some ideas before implementing them in Mitra, so it is unlikely to be developed into a finished product. But maybe someone will find the code interesting.
The server is built using apx_sdk and is compatible with fep-ae97-client.
Starting with version 4.5.0, Mitra expands collections when it distributes activities submitted to FEP-ae97 outboxes. That means portable actors like @nomad can create public posts, and they will be delivered to all their followers.
RE: https://mitra.social/objects/019784da-f56f-c1ee-b0f5-79f2dd9cb5de
FEP-ae97: Client-side activity signing has been updated: https://codeberg.org/fediverse/fep/pulls/682
I added a new section describing Media API after implementing it in Mitra v4.10.0.
The API is somewhat similar to Blossom API used by Nostr apps: media objects are identified by their SHA-256 digests, and can be mirrored to other gateways.
I also specified status codes for error responses.
I created a simple FEP-ae97 web client:
https://codeberg.org/silverpill/fep-ae97-web-client
It is written in #Rust using Leptos and APx. Everything is compiled to WebAssembly and the application can be served as a static website.
This technology stack is very promising, but I think it is not yet ready for anything serious. The development process is slower compared to JavaScript/TypeScript, and the resulting binary is huge - it's 4.5 MB already (without optimizations). So I am going to keep an eye on it, but focus on building another FEP-ae97 client using a different approach.
