BUG: Unknown Frame wrongly returned error code

[bathooman]

Description

• Type: Non-conformance Bug
• Priority: Minor

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Non-conformance Bug

Commit: 482610b

**Expected behavior **
The QUIC 1 RFC in section 12.4 states that:

An endpoint MUST treat the receipt of a frame of unknown type as a connection error of type FRAME_ENCODING_ERROR.

**Actual behavior **

When a client and a server are exchanging packets, receipt of an unknown frame will cause the generation of a CC with the PROTOCOL_VIOLATION error code.

I have attached the captured interaction between a QUIC client and a server containing the mentioned problem. The master secret log file is also attached so that one can decrypt the exchanged traffic.

unknown-frame-type.zip

[kazuho]

Thank you for reporting the issue.

I think the behavior is correct, we do support frame type 0x30 (DATAGRAM), and the draft states that PROTOCOL_VIOLATION MUST be sent when support for the DATAGRAM frame has not been indicated by the peer (https://datatracker.ietf.org/doc/html/draft-ietf-quic-datagram#section-3).

[bathooman]

You are right about this. I assume we can close this issue then.