[http] Work around stateful authentication schemes
As pointedly documented in RFC7230 section 2.3, HTTP is a stateless
protocol: each request message can be understood in isolation from any
other requests or responses. Various authentication schemes such as
NTLM break this fundamental property of HTTP and rely on the same TCP
connection being reused.
Work around these broken authentication schemes by ensuring that the
most recently pooled connection is reused for the subsequent
authentication retry.
Reported-by: Andreas Hammarskjöld <junior@2PintSoftware.com>
Tested-by: Andreas Hammarskjöld <junior@2PintSoftware.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[http] Rewrite HTTP core to support content encodings
Rewrite the HTTP core to allow for the addition of arbitrary content
encoding mechanisms, such as PeerDist and gzip.
The core now exposes http_open() which can be used to create requests
with an explicitly selected HTTP method, an optional requested content
range, and an optional request body. A simple wrapper provides the
preexisting behaviour of creating either a GET request or an
application/x-www-form-urlencoded POST request (if the URI includes
parameters).
The HTTP SAN interface is now implemented using the generic block
device translator. Individual blocks are requested using http_open()
to create a range request.
Server connections are now managed via a connection pool; this allows
for multiple requests to the same server (e.g. for SAN blocks) to be
completely unaware of each other. Repeated HTTPS connections to the
same server can reuse a pooled connection, avoiding the per-connection
overhead of establishing a TLS session (which can take several seconds
if using a client certificate).
Support for HTTP SAN booting and for the Basic and Digest
authentication schemes is now optional and can be controlled via the
SANBOOT_PROTO_HTTP, HTTP_AUTH_BASIC, and HTTP_AUTH_DIGEST build
configuration options in config/general.h.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown