Hi,
So: a bunch of us were discussing Prop224 Onion addresses, and their UX-malleability.
Specifically: that there are small bit fields in the current Prop224 Onion Address schema (eg: version, and other future structure?) which can be tweaked or amended without otherwise changing the functionality of the address, or without much changing what the user sees in the (say) browser address bar.
This is a point of significant concern because of issues like phishing and passing-off - by analogy: t0rpr0ject.0rg versus
torproject.org - and other games that can be played with a prop224 address now, or in future, to game user experience.
We discussed the existing "hash the public key before base-32 encoding" approach, but hashing breaks the prop224 key blinding.
Ian Goldberg - thank you Ian - offered this attractive solution: apply a *reversible* "All Or Nothing Transform" (AONT) to the entire Prop224 Onion Address, prior to Base32 Encoding.
This way, even a single-bit mutation of (say) version number will have a "diffusion" effect, impacting ~ N/2 of the bits whilst having O(1) cost and being reversible so as not to impact the rest of Prop224.
The result would be onion addresses which are less "tamperable" / more deterministic, that closer to one-and-only-one published onion address will correspond to an onion endpoint.
What does the panel think?
- alec
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