This change allows to upgrade a plain HTTP 1.x connection to TLS
according to RFC 2817. Switching the transport layer to TLS should be
possible without removing HttpClientCodec from the pipeline,
because HTTP/1.x layer of the protocol remains untouched by the switch
and the HttpClientCodec state must be retained for proper
handling the remainder of the response message,
per RFC 2817 requirement in point 3.3:
Once the TLS handshake completes successfully, the server MUST
continue with the response to the original request.
After this commit, the upgrade can be established by simply
inserting an SslHandler at the front of the pipeline after receiving
101 SWITCHING PROTOCOLS response, exactly as described in SslHander
documentation.
Modifications:
- Don't set HttpObjectDecoder into UPGRADED state if
101 SWITCHING_PROTOCOLS response contains HTTP/1.0 or HTTP/1.1 in
the protocol stack described by the Upgrade header.
- Skip pairing comparison for 101 SWITCHING_PROTOCOLS, similar
to 100 CONTINUE, since 101 is not the final response to the original
request and the final response is expected after TLS handshake.
Fixes#7293.
7995afee8f