The Fenrir Project

Transport, encryption, authentication protocol

This project is maintained by Luca Fulchir

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Fenrir's Blog

Welcome to the blog tracking the Fenrir project

This blog will be used to track and -why not- discuss all the choices, design features and advancements of the project, so you might find both technical posts and random thoughts.

Currently working on:

From Section Description
2017-04-25 Authentication connect Auth to handshake
2017-04-15 Handshake Reserved connections,syncookie,proofs
2017-03-30 Handshake Full security handshake, crypto typesafety
2017-03-23 plugins plugin typesafety

Reserved Handshakes

Handshakes Fenrir steteless

While re-implementing the full-security handshake in the rewrite of libFenrir, I came across the old problem of stateful vs stateless handshakes, and what it means for (D)DOS attacks.

After thinking about it for a while, let me introduce you to a slight modification of the full-security handshake to have the best world of bot stateful and stateless handshakes.

We will go through various design, and quickly analyze various solutions from TCP to minimaLT.

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Status Update

Update Fenrir

What is happening? Has the project stalled?
Not really, I’m just working behind the scenes.

Since you might also like some kind of report, I added a section “currently working on” on the blog page.

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Paper rejected

Update Fenrir paper ITA-SEC

I submitted a paper highlighting Fenrir to a security conference ITA-SEC.
The paper was rejected. Let’s see why and what it meas for the Fenrir project.

TLDR: no big deal, keep working.

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Status Update

Update libRaptorQ

A lot of time passed, what happened?

I have not been slacking, but I have not been working much on Fenrir lately.
That’s because a lot of work has been done in libRaptorQ, that Fenrir will use.

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Signal vs Federation


Recently the guys at Signal have published a blog post about their ideas on federation.

Our ideas differ, so let’s analyze the problem.

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I finally had some time to better think about multicast transmission and better analyze the problem. And I think I have a solution.

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I finally finished my master thesis, and the result can be found here.

Feel free to look at it to better understand the Fenrir protocol.

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Got Speed?

bandwidth delay RTT speed satellite

Every protocol has a limit on how quickly it can deliver things.

So how does Fenrir compare to the classical TCP?

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Anonymous Login

federation authentication anonymity

Obviously we support anonymous connection. But that’s not the same as an anonymous login.

By “Anonymous login” we mean being able to login to a 3rd party website without revealing our username.

With Fenrir, that’s pretty simple.

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It took me a lot more than expected, but finally I have a working implementation of the RaptorQ algorithm (RFC630)

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