From de14440b1f5b9e5beeda8b3e9945b6a840894dd63581cd1318472855db1fa2f0 Mon Sep 17 00:00:00 2001 From: Sergey Matveev Date: Wed, 17 Apr 2024 01:01:29 +0300 Subject: [PATCH] Note about BLAKE2s-XOF as a KDF --- doc/proto.texi | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/doc/proto.texi b/doc/proto.texi index a1af4d4..dc7c3d2 100644 --- a/doc/proto.texi +++ b/doc/proto.texi @@ -11,9 +11,10 @@ participant) and 24-bit big-endian packet counter. Reordered packets are dropped. 24-bit counter is long enough for very long talk sessions. Each packet is encrypted with ChaCha20 and authenticated with SipHash24. -The keys are generated during the handshake procedure with the server -and is shared among the other participants. The stream identifier -together with the packet counter is used as a nonce. +Their keys are generated from BLAKE2s-XOF, which is fed with completed +handshake's binding value. Then they are shared among the other +participants. The stream identifier together with the packet counter is +used as a nonce. It is tuned for 24Kbps bandwidth. But remember that it has additional 8B of MAC tag, 4B VoRS, 8B UDP and 40B IPv6 headers. -- 2.48.1