Re: [quicwg/base-drafts] allow dropping of Initial packets with invalid reserved bits (#2053)

[Kazuho Oku <[e-mail]>]

kazuho commented on this pull request.



> @@ -3278,9 +3278,10 @@ Reserved Bits (R):
 
 : The next two bits (those with a mask of 0x0c) of byte 0 are reserved.  These
   bits are protected using header protection (see Section 5.4 of {{QUIC-TLS}}).
-  The value included prior to protection MUST be set to 0.  An endpoint MUST
-  treat receipt of a packet that has a non-zero value for these bits after
-  removing protection as a connection error of type PROTOCOL_VIOLATION.
+  The value included prior to protection MUST be set to 0.  For Handshake and
+  0-RTT packets and endpoint MUST treat a non-zero value after removing
+  protection as a connection error of type PROTOCOL_VIOLATION. For Initial
+  packets, and endpoint MAY instead choose to drop the packet.

How about stating that, for Initial packets:
* an endpoint MUST ignore CRYPTO frames once it obtains Handshake keys
* an endpoint MUST ignore CONNECTION_CLOSE frames once it receives a Handshake packet
* an endpoint MUST ignore unexpected packet numbers found in an ACK frame

I think these three requirements are sufficient to address the attacks that happen _after_ 1 RTT.

-- 
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/2053#pullrequestreview-180095379