Re: [quicwg/base-drafts] Defend against endless Stateless Reset ping-pong (#1627)

[Marten Seemann <[e-mail]>]

marten-seemann commented on this pull request.



> +Note that Stateless Reset packets do not have any cryptographic protection.
+
+
+#### Looping {#reset-looping}
+
+The design of a Stateless Reset is such that it is indistinguishable from a
+valid packet.  This means that a Stateless Reset might trigger the sending of a
+Stateless Reset in response, which could lead to infinite exchanges.  An
+endpoint MUST use any one of the following measures to limit the sending of
+Stateless Reset:
+
+* An endpoint can remember the number of Stateless Reset packets that it has
+  sent and stop generating new Stateless Reset packets once a limit is reached.
+  Using separate limits for different remote addresses will ensure that
+  Stateless Reset packets can be used for some peers even when other peers have
+  exhausted limits.

I'm not sure if we discussed this anywhere, but if you're willing to keep some state around for a short period of time, wouldn't the easiest thing be to save the last 16 bytes of the packet (for each remote address), and if they match on two (non-identical) packets, you can be pretty sure that those are Stateless Resets.

-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/quicwg/base-drafts/pull/1627#pullrequestreview-142252403