diff --git a/proposals/2134-identity-hash-lookup.md b/proposals/2134-identity-hash-lookup.md index 11ea32583..6c3bbe63f 100644 --- a/proposals/2134-identity-hash-lookup.md +++ b/proposals/2134-identity-hash-lookup.md @@ -322,7 +322,7 @@ Further considered solutions are explored in https://signal.org/blog/contact-discovery/. Signal's eventual solution of using Software Guard Extensions (detailed in https://signal.org/blog/private-contact-discovery/) is considered impractical -for a federated network, as it requires specialized hardware. +for a federated network, as it requires specialised hardware. k-anonymity was considered as an alternative approach, in which the identity server would never receive a full hash of a 3PID that it did not already know @@ -410,10 +410,12 @@ Thus the conclusion is that while k-anon is harder to attack, it's unclear that this is actually enough of an obstacle to meaningfully stop a malicious IS. Therefore we should KISS and go for a simple hash lookup with a rotating pepper (which is not much harder than a static pepper, especially if our -initial implementation doesn't bother rotating the pepper). Rather than trying -to make the k-anon approach work, we'd be better off spending that time -figuring out how to store 3pids as hashes in the DB (and in 3pid bindings -etc), or how to decentralise ISes in general. +initial implementation doesn't bother rotating the pepper). Rather than +trying to make the k-anon approach work, we'd be better off spending that +time figuring out how to store 3pids as hashes in the DB (and in 3pid +bindings etc), or how to decentralise ISes in general. It's also worth noting +that a malicious server may fail to rotate the pepper, making the rotation +logic of questionable benefit. A radical model was also considered where the first portion of the k-anonyminity scheme was done with an identity server, and the second would