message-body in CONNECT response

[mnot@…]

As implemented in the real world, a successful response to a CONNECT request does not include a message-body. But this isn't stated in RFC 2817, and is actually forbidden by RFC 2616.

draft-luotonen-web-proxy-tunneling said:

Example of a response:

HTTP/1.0 200 Connection established Proxy-agent: Netscape-Proxy/1.1

...data tunnelled from the server...

After the empty line [that follows the message-headers], the proxy will start passing data from the client connection to the remote server connection

but RFC 2817 (5.3) removes the lack-of-message-body implication:

Any successful (2xx) response to a CONNECT request indicates that the proxy has established a connection to the requested host and port, and has switched to tunneling the current connection to that server connection.

[mnot@…]

Roy: Special-case CONNECT responses to indicate that if there's no Content-Length, the termination of the header fields indicates tunnelling has begun.

[dan.winship@…]

suggested text:

Note: Most existing implementations of CONNECT treat successful (2xx) responses to CONNECT requests as intrinsically having no message-body (ie, like responses to HEAD). For compatibility, servers SHOULD NOT include a non-empty message-body in a successful CONNECT response, and clients SHOULD treat a successful CONNECT response with no Content-Length or Transfer-Encoding headers as having no message-body.

[fielding@…]

Incorporated in [1570].

[julian.reschke@…]

From [1572]:

Note change for [1570] (see #250)

[julian.reschke@…]

From [1973]:

Mention CONNECT special-case in Changes from 2616 (see #250)