[HTTP/2] Don't send RST_STREAM back to server if we got RST_STREAM from it

[alnikola]

Description

When Http2Connection gets a RST_STREAM from the server, it calls Http2Stream.OnReset which can call Cancel method under some condition. Further, Cancel method calls CancelResponseBody which demands to send a RST_STREAM back to server if there is an unfinished response. Cancel does this by calling SendReset.

This behavior violates RFC which forbids sending a RST_STREAM in response to a RST_STREAM.

To avoid looping, an endpoint MUST NOT send a RST_STREAM in response to a RST_STREAM frame.

https://httpwg.org/specs/rfc7540.html#StreamErrorHandler

After receiving a RST_STREAM on a stream, the receiver MUST NOT send additional frames for that stream, with the exception of PRIORITY.

https://httpwg.org/specs/rfc7540.html#RST_STREAM

Regression?

The same logic exists in .NET 5.0.

[ghost]

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Issue Details

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Description

When Http2Connection gets a RST_STREAM from the server, it calls Http2Stream.OnReset which can call Cancel method under some condition. Further, Cancel method calls CancelResponseBody which demands to send a RST_STREAM back to server if there is an unfinished response. Cancel does this by calling SendReset.

This behavior violates RFC which forbids sending a RST_STREAM in response to a RST_STREAM.

To avoid looping, an endpoint MUST NOT send a RST_STREAM in response to a RST_STREAM frame.

https://httpwg.org/specs/rfc7540.html#StreamErrorHandler

After receiving a RST_STREAM on a stream, the receiver MUST NOT send additional frames for that stream, with the exception of PRIORITY.

https://httpwg.org/specs/rfc7540.html#RST_STREAM

Regression?

The same logic exists in .NET 5.0.

Author:	alnikola
Assignees:	-
Labels:	area-System.Net.Http
Milestone:	-

[karelz]

Triage: No customer impact so far, moving to Future.