Historically, "option httpclose" has always worked the same way. It
only mangles the "Connection" header in the request and the response
if needed, but does not affect the connection by itself, and ignores
any further data. It is dangerous to change this behaviour without
leaving any other alternative. If an active close is desired, it's
better to make use of "option forceclose" which does exactly what
it intends to do.
So as of now, "option httpclose" will only mangle the headers as
before, and will only affect the connection by itself when combined
with another connection-related option (eg: keepalive or server-close).
We basically have to mimmic the code of process_session() here, so
when the remote output is closed, we must abort otherwise we'll end
up with data which cannot leave the buffer.
By default this function returned 0 indicating an end of analysis.
This was not a problem as long as it was the last analyser in the
chain but becomes quite a big one now since it skips the forwarder
with auto_close enabled, causing some data to pass under the nose
of the last one undetected.
There were still several situations leading to CLOSE_WAIT sockets
remaining there forever because some complex transitions were
obviously not caught due to the impossibility to resync changes
between the request and response FSMs.
This patch now centralizes the global transaction state and feeds
it from both request and response transitions. That way, whoever
finishes first, there will be no issue for converging to the correct
state.
Some heavy use of the new debugging function has helped a lot. Maybe
those calls could be removed after some time. First tests are very
positive.
This function outputs to fd #-1 the status of request and response
buffers, the transaction states, the stream interface states, etc...
That way, it's easy to find that output in an strace report, correctly
placed WRT the other syscalls.
The data forwarders are analysers. As such, the have to check for
various situations on which they have to abort, one of them being
the lack of data with closed input. Now we don't leave the functions
anymore without performing these checks. This has solved the new
CLOSE_WAIT issue that became more noticeable since last patch.
It may happen that we forward a close just after we sent the last
chunk, because we forgot to clear the AUTO_CLOSE flag.
This issue caused some pages to be truncated depending on some
timing races. Issue initially reported by Cyril Bonté.
Released version 1.4-dev5 with the following main changes :
- [MINOR] server tracking: don't care about the tracked server's mode
- [MEDIUM] appsession: add "len", "prefix" and "mode" options
- [MEDIUM] appsession: add the "request-learn" option
- [BUG] Configuration parser bug when escaping characters
- [MINOR] CSS & HTML fun
- [MINOR] Collect & provide http response codes received from servers
- [BUG] Fix silly typo: hspr_other -> hrsp_other
- [MINOR] Add "a name" to stats page
- [MINOR] add additional "a href"s to stats page
- [MINOR] Collect & provide http response codes for frontends, fix backends
- [DOC] some small spell fixes and unifications
- [MEDIUM] Decrease server health based on http responses / events, version 3
- [BUG] format '%d' expects type 'int', but argument 5 has type 'long int'
- [BUG] config: fix erroneous check on cookie domain names, again
- [BUG] Healthchecks: get a proper error code if connection cannot be completed immediately
- [DOC] trivial fix for man page
- [MINOR] config: report all supported options for the "bind" keyword
- [MINOR] tcp: add support for the defer_accept bind option
- [MINOR] unix socket: report the socket path in case of bind error
- [CONTRIB] halog: support searching by response time
- [DOC] add a reminder about obsolete documents
- [DOC] point to 1.4 doc, not 1.3
- [DOC] option tcp-smart-connect was missing from index
- [MINOR] http: detect connection: close earlier
- [CLEANUP] sepoll: clean up the fd_clr/fd_set functions
- [OPTIM] move some rarely used fields out of fdtab
- [MEDIUM] fd: merge fd_list into fdtab
- [MAJOR] buffer: flag BF_DONT_READ to disable reads when not required
- [MINOR] http: add new transaction flags for keep-alive and content-length
- [MEDIUM] http request: parse connection, content-length and transfer-encoding
- [MINOR] http request: update the TX_SRV_CONN_KA flag on rewrite
- [MINOR] http request: simplify the test of no-data
- [MEDIUM] http request: simplify POST length detection
- [MEDIUM] http request: make use of pre-parsed transfer-encoding header
- [MAJOR] http: create the analyser which waits for a response
- [MINOR] http: pre-set the persistent flags in the transaction
- [MEDIUM] http response: check body length and set transaction flags
- [MINOR] http response: update the TX_CLI_CONN_KA flag on rewrite
- [MINOR] http: remove the last call to stream_int_return
- [IMPORT] import ebtree v5.0 into directory ebtree/
- [MEDIUM] build: switch ebtree users to use new ebtree version
- [CLEANUP] ebtree: remove old unused files
- [BUG] definitely fix regparm issues between haproxy core and ebtree
- [CLEANUP] ebtree: cast to char * to get rid of gcc warning
- [BUILD] missing #ifndef in ebmbtree.h
- [BUILD] missing #ifndef in ebsttree.h
- [MINOR] tools: add hex2i() function to convert hex char to int
- [MINOR] http: create new MSG_BODY sub-states
- [BUG] stream_sock: BUF_INFINITE_FORWARD broke splice on 64-bit platforms
- [DOC] option is "defer-accept", not "defer_accept"
- [MINOR] http: keep pointer to beginning of data
- [BUG] x-original-to: name was not set in default instance
- [MINOR] http: detect tunnel mode and set it in the session
- [BUG] config: fix error message when config file is not found
- [BUG] config: fix wrong handling of too large argument count
- [BUG] config: disable 'option httplog' on TCP proxies
- [BUG] config: fix erroneous check on cookie domain names
- [BUG] config: cookie domain was ignored in defaults sections
- [MINOR] config: support passing multiple "domain" statements to cookies
- [MINOR] ebtree: add functions to lookup non-null terminated strings
- [MINOR] config: don't report error on all subsequent files on failure
- [BUG] second fix for the printf format warning
- [BUG] check_post: limit analysis to the buffer length
- [MEDIUM] http: process request body in a specific analyser
- [MEDIUM] backend: remove HTTP POST parsing from get_server_ph_post()
- [MAJOR] http: completely process the "connection" header
- [MINOR] http: only consider chunk encoding with HTTP/1.1
- [MAJOR] buffers: automatically compute the maximum buffer length
- [MINOR] http: move the http transaction init/cleanup code to proto_http
- [MINOR] http: move 1xx handling earlier to eliminate a lot of ifs
- [MINOR] http: introduce a new synchronisation state : HTTP_MSG_DONE
- [MEDIUM] http: rework chunk-size parser
- [MEDIUM] http: add a new transaction flags indicating if we know the transfer length
- [MINOR] buffers: add buffer_ignore() to skip some bytes
- [BUG] http: offsets are relative to the buffer, not to ->som
- [MEDIUM] http: automatically re-aling request buffer
- [BUG] http: body parsing must consider the start of message
- [MINOR] new function stream_int_cond_close()
- [MAJOR] http: implement body parser
- [BUG] http: typos on several unlikely() around header insertion
- [BUG] stream_sock: wrong max computation on recv
- [MEDIUM] http: rework the buffer alignment logic
- [BUG] buffers: wrong size calculation for displaced data
- [MINOR] stream_sock: prepare for closing when all pending data are sent
- [MEDIUM] http: add two more states for the closing period
- [MEDIUM] http: properly handle "option forceclose"
- [MINOR] stream_sock: add SI_FL_NOLINGER for faster close
- [MEDIUM] http: make forceclose use SI_FL_NOLINGER
- [MEDIUM] session: set SI_FL_NOLINGER when aborting on write timeouts
- [MEDIUM] http: add some SI_FL_NOLINGER around server errors
- [MINOR] config: option forceclose is valid in frontends too
- [BUILD] halog: insufficient include path in makefile
- [MEDIUM] http: make the analyser not rely on msg being initialized anymore
- [MEDIUM] http: make the parsers able to wait for a buffer flush
- [MAJOR] http: add support for option http-server-close
- [BUG] http: ensure we abort data transfer on write error
- [BUG] last fix was overzealous and disabled server-close
- [BUG] http: fix erroneous trailers size computation
- [MINOR] stream_sock: enable MSG_MORE when forwarding finite amount of data
- [OPTIM] http: set MSG_MORE on response when a pipelined request is pending
- [BUG] http: redirects were broken by chunk changes
- [BUG] http: the request URI pointer is relative to the buffer
- [OPTIM] http: don't immediately enable reading on request
- [MINOR] http: move redirect messages to HTTP/1.1 with a content-length
- [BUG] http: take care of errors, timeouts and aborts during the data phase
- [MINOR] http: don't wait for sending requests to the server
- [MINOR] http: make the conditional redirect support keep-alive
- [BUG] http: fix cookie parser to support spaces and commas in values
- [MINOR] config: some options were missing for "redirect"
- [MINOR] redirect: add support for unconditional rules
- [MINOR] config: centralize proxy struct initialization
- [MEDIUM] config: remove the limitation of 10 reqadd/rspadd statements
- [MEDIUM] config: remove the limitation of 10 config files
- [CLEANUP] http: remove a remaining impossible condition
- [OPTIM] http: optimize a bit the construct of the forward loops
The cookie parser could be fooled by spaces or commas in cookie names
and values, causing the persistence cookie not to be matched if located
just after such a cookie. Now spaces found in values are considered as
part of the value, and spaces, commas and semi-colons found in values
or names, are skipped till next cookie name.
This fix must be backported to 1.3.
In case of a non-blocking socket, used for connecting to a remote
server (not localhost), the error reported by the health check
was most of a time one of EINPROGRESS/EAGAIN/EALREADY.
This patch adds a getsockopt(..., SO_ERROR, ...) call so now
the proper error message is reported.
It makes sense to permit a client to keep its connection when
performing a redirect to the same host. We only detect the fact
that the redirect location begins with a slash to use the keep-alive
(if the client supports it).
By default we automatically wait for enough data to fill large
packets if buf->to_forward is not null. This causes a problem
with POST/Expect requests which have a data size but no data
immediately available. Instead of causing noticeable delays on
such requests, simply add a flag to disable waiting when sending
requests.
In server-close mode particularly, the response buffer is marked for
no-auto-close after a response passed through. This prevented a POST
request from being aborted on errors, timeouts or anything if the
response was received before the request was complete.
If we enable reading of a request immediately after completing
another one, we end up performing small reads until the request
buffer is complete. This takes time and makes it harder to realign
the buffer when needed. Just enable reading when we need to.
The rq.u field is relative to buf->data, not to msg->sol. We have
to subtract msg->som everywhere this error was made. Maybe it will
be simpler to have a pointer to the buffer in the message and find
appropriate data there.
Many times we see a lot of short responses in HTTP (typically 304 on a
reload). It is a waste of network bandwidth to send that many small packets
when we know we can merge them. When we know that another HTTP request is
following a response, we set BF_EXPECT_MORE on the response buffer, which
will turn MSG_MORE on exactly once. That way, multiple short responses can
leave pipelined if their corresponding requests were also pipelined.
While it could be dangerous to enable MSG_MORE on infinite data (eg:
interactive sessions), it makes sense to enable it when we know the
chunk to be sent is just a part of a larger one.
We used to forward more trailers than required, causing a
desynchronization of the output. Now we schedule all for forwarding
as soon as we encounter them.
This option enables HTTP keep-alive on the client side and close mode
on the server side. This offers the best latency on the slow client
side, and still saves as many resources as possible on the server side
by actively closing connections. Pipelining is supported on both requests
and responses, though there is currently no reason to get pipelined
responses.
When too large a message lies in a buffer before parsing a new
request/response, we can now wait for previous outgoing data to
leave the buffer before attempting to parse again. After that
we can consider the opportunity to realign the buffer if needed.
The HTTP parser needed the msg structure to hold pre-initialized pointers.
This causes a trouble with keep-alive because if some data is still in the
buffer, the pointers can be anywhere after the data and later become invalid
when the buffer gets realigned.
It was not needed to rely on that since we have two valid information
in the buffer itself :
- buf->lr : last visited place
- buf->w + buf->send_max : beginning of next message
So by doing the maths only on those values, we can avoid doing tricks
on msg->som.
This option was disabled for frontends in the configuration because
it was useless in its initial implementation, though it was still
checked in the code. Let's officially enable it now.
When we catch an error from the server, speed up the connection
abort since we don't want to remain long with pending data in the
socket, and we want to be able to reuse our source port ASAP.
Doing this helps us flush the system buffers from all unread data. This
avoids having orphans when clients suddenly get off the net without
reading their entire response.
This new flag may be set by any user on a stream interface to tell
the underlying protocol that there is no need for lingering on the
socket since we know the other side either received everything or
does not care about what we sent.
This will typically be used with forced server close in HTTP mode,
where we want to quickly close a server connection after receiving
its response. Otherwise the system would prevent us from reusing
the same port for some time.
The "forceclose" option used to close the output channel to the
server once it started to respond. While this happened to work with
most servers, some of them considered this as a connection abort and
immediately stopped responding.
Now that we're aware of the end of a request and response, we're able
to trivially handle this option and properly close both sides when the
server's response is complete.
During this change it appeared that forwarding could be allowed when
the BF_SHUTW_NOW flag was set on a buffer, which obviously is not
acceptable and was causing some trouble. This has been fixed too and
is the reason for the MEDIUM status on this patch.
Since we'll soon be able to close a connection with remaining data in a
buffer, it becomes obvious that we can prepare to close when we're about
to send the last chunk of data and not the whole buffer.
This error was triggered by requests not starting at the beginning
of the buffer. It cannot happen with earlier versions though it might
be a good idea to fix it anyway.
There were still issues with the buffer alignment. Now we ensure
that we always align it before a request or response is completely
parsed if there is less than maxrewrite bytes free at the end. In
practice, it's not called that often and ensures we can always work
as expected.
Since the introduction of the automatic sizing of buffers during reads,
a bug appeared where the max size could be negative, causing large
chunks of memory to be overwritten during recv() calls if a read pointer
was already past the buffer's limit.
In many places where we perform header insertion, an error control
is performed but due to a mistake, it cannot match any error :
if (unlikely(error) < 0)
instead of
if (unlikely(error < 0))
This prevents error 400 responses from being sent when the buffer is
full due to many header additions. This must be backported to 1.3.
The body parser will be used in close and keep-alive modes. It follows
the stream to keep in sync with both the request and the response message.
Both chunked transfer-coding and content-length are supported according to
RFC2616.
The multipart/byterange encoding has not yet been implemented and if not
seconded by any of the two other ones, will be forwarded till the close,
as requested by the specification.
Both the request and the response analysers converge into an HTTP_MSG_DONE
state where it will be possible to force a close (option forceclose) or to
restart with a fresh new transaction and maintain keep-alive.
This change is important. All tests are OK but any possible behaviour
change with "option httpclose" might find its root here.
