%Fi: Frontend IP
%Fp: Frontend Port
%Si: Server IP
%Sp: Server Port
%Ts: Timestamp
%rt: HTTP request counter
%H: hostname
%pid: PID
+X: Hexadecimal represenation
The +X mode in logformat displays hexadecimal for the following flags
%Ci %Cp %Fi %Fp %Bi %Bp %Si %Sp %Ts %ct %pid
rename logformat_write_string() to lf_text()
Optimize size computation
The ACL matches rely on the extract_cookie_value() function as used for
for patterns. This permits ACLs to match cookie values based on the cookie
name instead of having to perform substring matching on the cookie header.
Sometimes it is desirable to forward a particular request to a specific
server without having to declare a dedicated backend for this server. This
can be achieved using the "use-server" rules. These rules are evaluated after
the "redirect" rules and before evaluating cookies, and they have precedence
on them. There may be as many "use-server" rules as desired. All of these
rules are evaluated in their declaration order, and the first one which
matches will assign the server.
memcmp()/strcmp() calls were needed in different parts of code to determine
the status code. Each new status code introduces new calls, which can become
inefficient and source of bugs.
This patch reorganizes the code to rely on a numeric status code internally
and to be hopefully more generic.
Previously, the stats admin page required POST parameters to be provided
exactly in the same order as the HTML form.
This patch allows to handle those parameters in any orders.
Also, note that haproxy won't alter server states anymore if backend or server
names are ambiguous (duplicated names in the configuration) to prevent
unexpected results (the same should probably be applied to the stats socket).
Olufemi Omojola provided a config and a core showing a possible crash
when captures are configured on a TCP-mode frontend which branches to
an HTTP backend. The reason is that being in TCP mode, the frontend
does not allocate capture pools for the request, but the HTTP backend
tries to use them and dies on the NULL.
While such a config has long been unlikely to happen, it looks like
people using websocket tend to do this more often now.
Change the control to use the pointer instead of the number of captures
to know when to log.
This bug was reported in 1.4.20, so it must be backported there.
Merge http_sess_log() and tcp_sess_log() to sess_log() and move it to
log.c
A new field in logformat_type define if you can use a logformat
variable in TCP or HTTP mode.
doc: log-format in tcp mode
Note that due to the way log buffer allocation currently works, trying to
log an HTTP request without "option httplog" is still not possible. This
will change in the near future.
Commits 5c6209 and 072930 were aimed at avoiding undesirable PUSH flags
when forwarding chunked data, but had the undesired effect of causing
data advertised by content-length to be affected by the delayed ACK too.
This can happen when the data to be forwarded are small enough to fit into
a single send() call, otherwise the BF_EXPECT_MORE flag would be removed.
Content-length data don't need the BF_EXPECT_MORE flag since the low-level
forwarder already knows it can safely rely on bf->to_forward to set the
appropriate TCP flags.
Note that the issue is only observed in requests at the moment, though the
later introduction of server-side keep-alive could trigger the issue on the
response path too.
Special thanks to Randy Shults for reporting this issue with a lot of
details helping to reproduce it.
The fix must be backported to 1.4.
When a request completes on a server and the server connection is closed
while the client connection stays open, the HTTP engine releases all server
connection slots and scans the queues to offer the connection slot to
another pending request.
An issue happens when the released connection allows other requests to be
dequeued : may_dequeue_tasks() relies on srv->served which is only decremented
by sess_change_server() which itself is only called after may_dequeue_tasks().
This results in no connection being woken up until another connection terminates
so that may_dequeue_tasks() is called again.
This fix is minimalist and only moves sess_change_server() earlier (which is
safe). It should be reworked and the code factored out so that the same occurrence
in session.c shares the same code.
This bug has been there since the introduction of option-http-server-close and
the fix must be backported to 1.4.
Since commit 115acb97, chunk size was limited to 256MB. There is no reason for
such a limit and the comment on the code suggests a missing zero. However,
increasing the limit past 2 GB causes trouble due to some 32-bit subtracts
in various computations becoming negative (eg: buffer_max_len). So let's limit
the chunk size to 2 GB - 1 max.
commit a1cc3811 introduced an undesirable \0\n ending on HTTP log messages. This
is because of an extra character count passed to __send_log() which causes the LF
to be appended past the \0. Some syslog daemons thus log an extra empty line. The
fix is obvious. Fix the function comments to remind what they expect on their input.
This is past 1.5-dev7 regression so there's no backport needed.
http_sess_log now use the logformat linked list to make the log
string, snprintf is not used for speed issue.
CLF mode also uses logformat.
NOTE: as of now, empty fields in CLF now are "" not "-" anymore.
Marcello Gorlani reported that commit 5e205524ad
(BUG: http: re-enable TCP quick-ack upon incomplete HTTP requests) broke build
on FreeBSD.
Moving the include lower fixes the issue. This must be backported to 1.4 too.
These ones are invalid and blocked unless "option accept-invalid-http-request"
is specified in the frontend. In any case, the faulty request is logged.
Note that some of the remaining invalid chars are still not checked against,
those are the invalid ones between 32 and 127 :
34 ('"'), 60 ('<'), 62 ('>'), 92 ('\'), 94 ('^'),
96 ('`'), 123 ('{'), 124 ('|'), 125 ('}')
Using a lookup table might be better at some point.
The HTTP request parser was considering that any non-LWS char was
par of the URI. Unfortunately, this allows control chars to be sent
in the URI, sometimes resulting in backend servers misbehaving, for
instance when they interprete \0 as an end of string and respond
with plain HTTP/0.9 without headers, that haproxy blocks as invalid
responses.
RFC3986 clearly states the list of allowed characters in a URI. Even
non-ASCII chars are not allowed. Unfortunately, after having run 10
years with these chars allowed, we can't block them right now without
an optional workaround. So the first step consists in only blocking
control chars. A later patch will allow non-ASCII only when an appropriate
option is enabled in the frontend.
Control chars are 0..31 and 127, with the exception of 9, 10 and 13
(\t, \n, \r).
New option "http-send-name-header" specifies the name of a header which
will hold the server name in outgoing requests. This is the name of the
server the connection is really sent to, which means that upon redispatches,
the header's value is updated so that it always matches the server's name.
This pattern previously was limited to type IP. With the new header
extraction function, it becomes possible to extract strings, so that
the header can be returned as a string. This will not change anything
to existing configs, as string will automatically be converted to IP
when needed. However, new configs will be able to use IPv6 addresses
from headers in stick-tables, as well as stick on any non-IP header
(eg: host, user-agent, ...).
The new function does not return IP addresses but header values instead,
so that the caller is free to make what it want of them. The conversion
is not quite clean yet, as the previous test which considered that address
0.0.0.0 meant "no address" is still used. A different IP parsing function
should be used to take this into account.
Now strings and data blocks are stored in the temp_pattern's chunk
and matched against this one.
The rdp_cookie currently makes extensive use of acl_fetch_rdp_cookie()
and will be a good candidate for the initial rework so that ACLs use
the patterns framework and not the other way around.
IPv4 and IPv6 addresses are now stored into temp_pattern instead of
the dirty hack consisting into storing them into the consumer's target
address.
Some refactoring should now be possible since the methods used to fetch
source and destination addresses are similar between patterns and ACLs.
All ACL fetches which return integer value now store the result into
the temporary pattern struct. All ACL matches which rely on integer
also get their value there.
Note: the pattern data types are not set right now.
By default we disable TCP quick-acking on HTTP requests so that we
avoid sending a pure ACK immediately followed by the HTTP response.
However, if the client sends an incomplete request in a short packet,
its TCP stack might wait for this packet to be ACKed before sending
the rest of the request, delaying incoming requests by up to 40-200ms.
We can detect this undesirable situation when parsing the request :
- if an incomplete request is received
- if a full request is received and uses chunked encoding or advertises
a content-length larger than the data available in the buffer
In these situations, we re-enable TCP quick-ack if we had previously
disabled it.
This patch settles the 2 loggers limitation.
Loggers are now stored in linked lists.
Using "global log", the global loggers list content is added at the end
of the current proxy list. Each "log" entries are added at the end of
the proxy list.
"no log" flush a logger list.
Stream interfaces used to distinguish between client and server addresses
because they were previously of different types (sockaddr_storage for the
client, sockaddr_in for the server). This is not the case anymore, and this
distinction is confusing at best and has caused a number of regressions to
be introduced in the process of converting everything to full-ipv6. We can
now remove this and have a much cleaner code.
This patch introduces hdr_len, path_len and url_len for matching these
respective parts lengths against integers. This can be used to detect
abuse or empty headers.
Commit 588bd4 fixed header parsing so that trailing spaces were not part
of the returned string. Unfortunately, if a header only had spaces, the
last spaces were trimmed past the beginning of the value, causing a negative
length to be returned.
A quick code review shows that there should be no impact since the only
places where the vlen is used are either compared to a specific value or
with explicit contents (eg: digits).
This must be backported to 1.4.
These requests are mainly monitor requests, as well as stats requests when
the stats are processed by the frontend. Having this counter helps explain
the difference in number of sessions that is sometimes observed between a
frontend and a backend.
Sometimes a bad content-length header is encountered and this causes
an abort. It's hard to debug without a trace, so let's take a capture
of the contents when this happens.
If a server starts to respond but stops before the body, then we
capture the truncated response. We don't do this on the request
because it would happen too often upon stupid attacks.
Trailing spaces after headers were not trimmed, only the leading ones
were. An issue was detected today with a content-length value which
was padded with spaces and which was rejected. Recent updates to the
http-bis draft made it a lot more clear that such spaces must be ignored,
so this is what this patch does.
It should be backported to 1.4.
Many inet_ntop calls were partially right, which was hard to detect given
the complex combinations. Some of them were relying on the listener's proto
instead of the address itself, which could have been different when dealing
with an accept-proxy connection.
The new addr_to_str() function does the dirty job and returns the family, which
makes it particularly suited to calls from switch/case statements. A large number
of if/else statements were removed and the stats output could even be cleaned up
in the case of session dump.
As a side effect of doing this, the resulting code is smaller by almost 1kB.
All changed parts have been tested and provided expected output.
If "option forwardfor" has the "if-none" argument, then the header is
only added when the request did not already have one. This option has
security implications, and should not be set blindly.
This is used to perform cookie-based stickiness with table replication
between multiple masters and across restarts. This partially overrides
some of the appsession capabilities.
The motivation for this is to allow iteration of all the connections
of a server without the expense of iterating over the global list
of connections.
The first use of this will be to implement an option to close connections
associated with a server when is is marked as being down or in maintenance
mode.
gcc (Debian 4.6.0-2) 4.6.1 20110329 (prerelease)
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
...
src/proto_http.c:3029:14: warning: variable ‘del_cl’ set but not used [-Wunused-but-set-variable]
In file included from ebtree/eb64tree.c:23:0:
ebtree/eb64tree.h: In function ‘__eb64_lookup’:
ebtree/eb64tree.h:128:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
ebtree/eb64tree.h: In function ‘__eb64i_lookup’:
ebtree/eb64tree.h:180:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
In file included from ebtree/ebpttree.h:26:0,
from ebtree/ebimtree.c:23:
ebtree/eb64tree.h: In function ‘__eb64_lookup’:
ebtree/eb64tree.h:128:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
ebtree/eb64tree.h: In function ‘__eb64i_lookup’:
ebtree/eb64tree.h:180:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
In file included from ebtree/ebpttree.h:26:0,
from ebtree/ebistree.h:25,
from ebtree/ebistree.c:23:
ebtree/eb64tree.h: In function ‘__eb64_lookup’:
ebtree/eb64tree.h:128:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
ebtree/eb64tree.h: In function ‘__eb64i_lookup’:
ebtree/eb64tree.h:180:6: warning: variable ‘node_bit’ set but not used [-Wunused-but-set-variable]
Bashkim Kasa reported that the stats admin page did not work when colons
were used in server or backend names. This was caused by url-encoding
resulting in ':' being sent as '%3A'. Now we systematically decode the
field names and values to fix this issue.
Now that we support the http-no-delay mode, we can optimize HTTP
chunking again by always waiting for more data to come until the
last chunk is met.
This patch may or may not be backported to 1.4, it's not a big deal,
it will mainly help for chunks which are aligned with the buffer size.
There are some very rare server-to-server applications that abuse the HTTP
protocol and expect the payload phase to be highly interactive, with many
interleaved data chunks in both directions within a single request. This is
absolutely not supported by the HTTP specification and will not work across
most proxies or servers. When such applications attempt to do this through
haproxy, it works but they will experience high delays due to the network
optimizations which favor performance by instructing the system to wait for
enough data to be available in order to only send full packets. Typical
delays are around 200 ms per round trip. Note that this only happens with
abnormal uses. Normal uses such as CONNECT requests nor WebSockets are not
affected.
When "option http-no-delay" is present in either the frontend or the backend
used by a connection, all such optimizations will be disabled in order to
make the exchanges as fast as possible. Of course this offers no guarantee on
the functionality, as it may break at any other place. But if it works via
HAProxy, it will work as fast as possible. This option should never be used
by default, and should never be used at all unless such a buggy application
is discovered. The impact of using this option is an increase of bandwidth
usage and CPU usage, which may significantly lower performance in high
latency environments.
This change should be backported to 1.4 since the first report of such a
misuse was in 1.4. Next patch will also be needed.
Commit 57f5c1 used to provide a nice improvement on chunked encoding since
it ensured that we did not set a PUSH flag for every chunk or buffer data
part of a chunked transfer.
Some applications appear to erroneously abuse HTTP chunking in order to
get interactive exchanges between a user agent and an origin server with
very small chunks. While it happens to work through haproxy, it's terribly
slow due to the latency added after passing each chunk to the system, who
could wait up to 200ms before pushing them onto the wire.
So we need an interactive mode for such usages. In the mean time, step back
on the optim, but not completely, so that we still keep the flag as long as
we know we're not finished with the current chunk.
This change should be backported to 1.4 too as the issue was discovered
with it.
This status code is used in response to requests matching "monitor-uri".
Some users need to adjust it to fit their needs (eg: make some strings
appear there). As it's already defined as a chunked string and used
exactly like other status codes, it makes sense to make it configurable
with the usual "errorfile", "errorloc", ...
Some people like to make the monitoring URL testable from unsafe locations.
Reporting haproxy's existence there can sometimes be problematic. This patch
should not be backported to 1.4 because it is possible, eventhough unlikely,
that some scripts rely on this word to appear there.
When doing fix 24581bae02 to correctly handle
response cookies, an unfortunate typo was inserted in the less likely code
path, resulting in a risk of crash when cookie-based persistence is enabled
and the server emits a cookie with several spaces around the equal sign.
This bug was noticed during a code backport. Its effects were never reported
because this situation is very unlikely to appear, but it can be provoked on
purpose by the server.
This patch must be backported to 1.4 versions which contain the fix above
(anything > 1.4.8), and to similar 1.3 versions > 1.3.25. 1.5-dev versions
after 1.5-dev2 are affected too.
Despite much care around handling the content-length as a 64-bit integer,
forwarding was broken on 32-bit platforms due to the 32-bit nature of
the ->to_forward member of the "buffer" struct. The issue is that this
member is declared as a long, so while it works OK on 64-bit platforms,
32-bit truncate the content-length to the lower 32-bits.
One solution could consist in turning to_forward to a long long, but it
is used a lot in the critical path, so it's not acceptable to perform
all buffer size computations on 64-bit there.
The fix consists in changing the to_forward member to a strict 32-bit
integer and ensure in buffer_forward() that only the amount of bytes
that can fit into it is considered. Callers of buffer_forward() are
responsible for checking that their data were taken into account. We
arbitrarily ensure we never consider more than 2G at once.
That's the way it was intended to work on 32-bit platforms except that
it did not.
This issue was tracked down hard at Exosec with Bertrand Jacquin,
Thierry Fournier and Julien Thomas. It remained undetected for a long
time because files larger than 4G are almost always transferred in
chunked-encoded format, and most platforms dealing with huge contents
these days run on 64-bit.
The bug affects all 1.5 and 1.4 versions, and must be backported.
Since we now have the copy of the target in the session, use it instead
of relying on the SI for it. The SI drops the target upon unregister()
so applets such as stats were logged as "NOSRV".
Johannes Smith reported some wrong retries count in logs associated with bad
requests. The cause was that the conn_retries field in the stream interface
was only initialized when attempting to connect, but is used when logging,
possibly with an uninitialized value holding last connection's conn_retries.
This could have been avoided by making use of a stream interface initializer.
This bug is 1.5-specific.
And also rename "req_acl_rule" "http_req_rule". At the beginning that
was a bit confusing to me, especially the "req_acl" list which in fact
holds what we call rules. After some digging, it appeared that some
part of the code is 100% HTTP and not just related to authentication
anymore, so let's move that part to HTTP and keep the auth-only code
in auth.c.
Right now, http-request rules are not evaluated if the URL matches the
stats request. This is quite unexpected. For instance, in the config
below, an abuser present in the abusers list will not be prevented access
to the stats.
listen pub
bind :8181
acl abuser src -f abusers.lst
http-request deny if abuser
stats uri /stats
It is not a big deal but it's not documented as such either. For 1.5, let's
have both lists be evaluated in turn, until one blocks. For 1.4 we'll simply
update the doc to indicate that.
Also instead of duplicating the code, the patch factors out the list walking
code. The HTTP auth has been moved slightly earlier, because it was set after
the header addition code, but we don't need to add headers to a request we're
dropping.
It's very annoying that frontend and backend stats are merged because we
don't know what we're observing. For instance, if a "listen" instance
makes use of a distinct backend, it's impossible to know what the bytes_out
means.
Some points take care of not updating counters twice if the backend points
to the frontend, indicating a "listen" instance. The thing becomes more
complex when we try to add support for server side keep-alive, because we
have to maintain a pointer to the backend used for last request, and to
update its stats. But we can't perform such comparisons anymore because
the counters will not match anymore.
So in order to get rid of this situation, let's have both frontend AND
backend stats in the "struct proxy". We simply update the relevant ones
during activity. Some of them are only accounted for in the backend,
while others are just for frontend. Maybe we can improve a bit on that
later, but the essential part is that those counters now reflect what
they really mean.
This patch turns internal server addresses to sockaddr_storage to
store IPv6 addresses, and makes the connect() function use it. This
code already works but some caveats with getaddrinfo/gethostbyname
still need to be sorted out while the changes had to be merged at
this stage of internal architecture changes. So for now the config
parser will not emit an IPv6 address yet so that user experience
remains unchanged.
This change should have absolutely zero user-visible effect, otherwise
it's a bug introduced during the merge, that should be reported ASAP.
This one has been removed and is now totally superseded by ->target.
To get the server, one must use target_srv(&s->target) instead of
s->srv now.
The function ensures that non-server targets still return NULL.
s->prev_srv is used by assign_server() only, but all code paths leading
to it now take s->prev_srv from the existing s->srv. So assign_server()
can do that copy into its own stack.
If at one point a different srv is needed, we still have a copy of the
last server on which we failed a connection attempt in s->target.
When dealing with HTTP keep-alive, we'll have to know if we can reuse
an existing connection. For that, we'll have to check if the current
connection was made on the exact same target (referenced in the stream
interface).
Thus, we need to first assign the next target to the session, then
copy it to the stream interface upon connect(). Later we'll check for
equivalence between those two operations.
This is in fact where those parts belong to. The old data_state was replaced
by applet.state and is now initialized when the applet is registered. It's
worth noting that the applet does not need to know the session nor the
buffer anymore since everything is brought by the stream interface.
It is possible that having a separate applet struct would simplify the
code but that's not a big deal.
With HTTP keep-alive, logging the right server name will be quite
complex because the assigned server will possibly change before we log.
Also, when we want to log accesses to an applet, it's not easy because
the applet becomes NULL again before logging.
The logged server's name is now taken from the target stored in the
stream interface. That way we can log an applet, a server name, or we
could even log a proxy or anything else if we wanted to. Ideally the
session should contain a desired target which is the one which should
be logged.
I/O handlers are still delicate to manipulate. They have no type, they're
just raw functions which have no knowledge of themselves. Let's have them
declared as applets once for all. That way we can have multiple applets
share the same handler functions and we can store their names there. When
we later need to add more parameters (eg: usage stats), we'll be able to
do so in the applets themselves.
The CLI functions has been prefixed with "cli" instead of "stats" as it's
clearly what is going on there.
The applet descriptor in the stream interface should get all the applet
specific data (st0, ...) but this will be done in the next patch so that
we don't pollute this one too much.
Similar to the stats socket bug, we must check that the proxy is not disabled
before trying to enable/disable a server.
Even if a disabled proxy is not displayed, someone can inject a faulty proxy
name in the POST parameters. So, we must ensure that no disabled proxy can be
used.
Bryan Talbot reported that POST requests with a query string were not
correctly processed if the hash parameter was the first one, because
the delimiter that was looked for to trigger the parsing was '&' instead
of '?'.
Also, while checking the code, it became apparent that it was enough for
a query string to be present in the request for POST parameters to be
ignored, even if the url_param was in the body and not in the URL.
The code has then been fixed like this :
1) look for URL param. If found, return it.
2) if no URL param was found and method is POST, then look it up into
the body
The code now seems to pass all request combinations.
This patch must be backported to 1.4 since 1.4 is equally broken right now.
Till now, the forwarding code was making use of the hdr_content_len member
to hold the size of the last chunk parsed. As such, it was reset after being
scheduled for forwarding. The issue is that this entry was reset before the
data could be viewed by backend.c in order to parse a POST body, so the
"balance url_param check_post" did not work anymore.
In order to fix this, we need two things :
- the chunk size (reset upon every forward)
- the total body size (not reset)
hdr_content_len was thus replaced by the former (hence the size of the patch)
as it makes more sense to have it stored that way than the way around.
This patch should be backported to 1.4 with care, considering that it affects
the forwarding code.
It seems like if a response message is chunked and the chunk size wraps
at the end of the buffer and the crlf sequence is incomplete, then we
can forward a wrong chunk size due to incorrect handling of the wrapped
size. It seems extremely unlikely to occur on real traffic (no reason to
have half of the CRLF after a chunk) but nothing prevents it from being
possible.
This fix must be backported to 1.4.
req_acl was used instead of req_acl_final. As a matter of luck, both
happen to be the same at this point, but this is not granted in the
future.
This fix should be backported to 1.4.
Some browsers send POST requests in several packets, which was not supported
by the "stats admin" function.
This patch allows to wait for more data when they are not fully received
(we are still limited to a certain size defined by the buffer size minus its
reserved space).
It also adds support for the "Expect: 100-Continue" header.
Stefan Behte reported a strange case where depending on the position of
the Connection header in the header list, some headers added after it
were or were not usable in "balance hdr()". The reason is that when the
last header is removed, the list's tail was not updated, so any header
added after that one was not visible from the list.
This fix must be backported to 1.4 and possibly 1.3.
It's better to avoid sticking on empty parameter values, as this almost
always indicates a missing parameter. Otherwise it's easy to enter a
situation where all new visitors stick to the same server.
Since haproxy 1.4.9, combining option httpclose and option
http-pretend-keepalive can leave the connections opened until the backend
keep-alive timeout is reached, providing bad performances.
The same can occur when the proxy is in tunnel mode.
This patch ensures that the server side connection is closed after the
response and ignore http-pretend-keepalive in tunnel mode.
We've had several issues related to data transfers. First, if a
client aborted an upload before the server started to respond, it
would get a 502 followed by a 400. The same was true (in the other
way around) if the server suddenly aborted while the client was
uploading the data.
The flags reported in the logs were misleading. Request errors could
be reported while the transfer was stopped during the data phase. The
status codes could also be overwritten by a 400 eventhough the start
of the response was transferred to the client.
The stats were also wrong in case of data aborts. The server or the
client could sometimes be miscredited for being the author of the
abort depending on where the abort was detected. Some client aborts
could also be accounted as request errors and some server aborts as
response errors.
Now it seems like all such issues are fixed. Since we don't have a
specific state for data flowing from the client to the server
before the server responds, we're still counting the client aborted
transfers as "CH", and they become "CD" when the server starts to
respond. Ideally a "P" state would be desired.
This patch should be backported to 1.4.
HTTP pipelining currently needs to monitor the response buffer to wait
for some free space to be able to send a response. It was not possible
for the HTTP analyser to be called based on response buffer activity.
Now we introduce a new buffer flag BF_WAKE_ONCE which is set when the
HTTP request analyser is set on the response buffer and some activity
is detected. This is not clean at all but once of the only ways to fix
the issue before we make it possible to register events for analysers.
Also it appeared that one realign condition did not cover all cases.
This counter will help quickly spot whether there are new errors or not.
It is also assigned to each capture so that a script can keep trace of
which capture was taken when.
It is possible to block on incorrectly chunked requests or responses,
but this becomes very hard to debug when it happens once in a while.
This patch adds the ability to also capture incorrectly chunked requests
and responses. The chunk will appear in the error buffer and will be
verifiable with the usual "show errors". The incorrect byte will match
the error location.
Error captures did only support contiguous messages. This is annoying
for capturing chunking errors, so let's ensure the function is able to
copy wrapped messages.
When haproxy parses chunk-encoded data that are scheduled to be sent, it is
possible that the other end is closed (mainly due to a client abort returning
as an error). The message state thus changes to HTTP_MSG_ERROR and the error
is reported as a chunk parsing error ("PD--") while it is not. Detect this
case before setting the flags and set the appropriate flag in this case.
Debugging parsing errors can be greatly improved if we know what the parser
state was and what the buffer flags were (especially for closed inputs/outputs
and full buffers). Let's add that to the error snapshots.
When forwarding chunk-encoded data, each chunk gets a TCP PUSH flag when
going onto the wire simply because the send() function does not know that
some data remain after it (next chunk). Now we set the BF_EXPECT_MORE flag
on the buffer if the chunk size is not null. That way we can reduce the
number of packets sent, which is particularly noticeable when forwarding
compressed data, especially as it requires less ACKs from the client.
When a header is removed, the previous header's next pointer is updated
to reflect the next of the current header. However, when cycling through
the loop, we update the prev pointer to point to the deleted header, which
means that if we delete another header, it's the deleted header's next
pointer that will be updated, leaving the deleted header in the list with
a null length, which is forbidden.
We must just not update the prev pointer after a removal.
This bug was present when either "reqdel" and "rspdel" removed two consecutive
headers. It could also occur when removing cookies in either requests or
responses, but since headers were the last header processing, the issue
remained unnoticed.
Issue reported by Hank A. Paulson.
This fix must be ported to 1.4 and possibly 1.3.
Cookies in indirect mode are removed from the cookie header. Three pointers
ought to be updated when appsession cookies are processed next, but were not.
The result is that a memcpy() can be called with a negative value causing the
process to crash. It is not sure whether this can be remotely exploited or not.
(cherry picked from commit c5f3749aa3ccfdebc4992854ea79823d26f66213)
In out of memory conditions, the ->destroy function would free all
possibly allocated pools from the current appsession, including those
that were not yet allocated nor assigned, which used to point to a
previous allocation, obviously resulting in a segfault.
(cherry picked from commit 75eae485921d3a6ce197915c769673834ecbfa5c)
In case of out of memory, it was possible to write to a null pointer
when capturing response cookies due to a missing "else" block. The
request handling was fine though.
(cherry picked from commit 62e3604d7dd27741c0b4c9e27d9e7c73495dfc32)
Enhance pattern convs and fetch argument parsing, now fetchs and convs callbacks used typed args.
Add more details on error messages on parsing pattern expression function.
Update existing pattern convs and fetchs to new proto.
Create stick table key type "binary".
Manage Truncation and padding if pattern's fetch-converted result don't match table key size.
This option makes haproxy preserve any persistence cookie emitted by
the server, which allows the server to change it or to unset it, for
instance, after a logout request.
(cherry picked from commit 52e6d75374c7900c1fe691c5633b4ae029cae8d5)
This match returns true when the request calling it is the first one of
a connection.
(cherry picked from commit 922ca979c50653c415852531f36fe409190ad76b)
When we're enabling a server again (unix CLI or stats interface), we must not mark
it completely up because it can take a while before a failure is detected. So we
mark it one step above failure, which means it's up but will be marked down upon
first failure.
(cherry picked from commit 83c3e06452457ed5660fc814cbda5bf878bf19a2)
The stats web interface must be read-only by default to prevent security
holes. As it is now allowed to enable/disable servers, a new keyword
"stats admin" is introduced to activate this admin level, conditioned by ACLs.
(cherry picked from commit 5334bab92ca7debe36df69983c19c21b6dc63f78)
Based on a patch provided by Judd Montgomery, it is now possible to
enable/disable servers from the stats web interface. This allows to select
several servers in a backend and apply the action to them at the same time.
Currently, there are 2 known limitations :
- The POST data are limited to one packet
(don't alter too many servers at a time).
- Expect: 100-continue is not supported.
(cherry picked from commit 7693948766cb5647ac03b48e782cfee2b1f14491)
If a maxidle or maxlife parameter is set on the persistence cookie in
insert mode and the client did not provide a recent enough cookie,
then we emit a new cookie with a new last_seen date and the same
first_seen (if maxlife is set). Recent enough here designates a
cookie that would be rounded to the same date. That way, we can
refresh a cookie when required without doing it in all responses.
If the request did not contain such parameters, they are set anyway.
This means that a monitoring request that is forced to a server will
get an expiration date anyway, but this should not be a problem given
that the client is able to set its cookie in this case. This also
permits to force an expiration date on visitors who previously did
not have one.
If a request comes with a dated cookie while no date check is performed,
then a new cookie is emitted with no date, so that we don't risk dropping
the user too fast due to a very old date when we re-enable the date check.
All requests that were targetting the correct server and which had their
expiration date added/updated/removed in the response cookie are logged
with the 'U' ("updated") flag instead of the 'I' ("inserted"). So very
often we'll see "VU" instead of "VN".
(cherry picked from commit 8b3c6ecab6d37be5f3655bc3a2d2c0f9f37325eb)
If a cookie comes in with a first or last date, and they are configured on
the backend, they're checked. If a date is expired or too far in the future,
then the cookie is ignored and the specific reason appears in the cookie
field of the logs.
(cherry picked from commit faa3019107eabe6b3ab76ffec9754f2f31aa24c6)
The set-cookie status flags were not very handy and limited. Reorder
them to save some room for additional values and add the "U" flags
(for Updated expiration date) that will be used with expirable cookies
in insert mode.
(cherry picked from commit 5bab52f821bb0fa99fc48ad1b400769e66196ece)
In all cookie persistence modes but prefix, we now support cookies whose
value is suffixed with some contents after a vertical bar ('|'). This will
be used to pass an optional expiration date. So as of now we only consider
the part of the cookie value which is used before the vertical bar.
(cherry picked from commit a4486bf4e5b03b5a980d03fef799f6407b2c992d)
Some configs may involve httpclose in a frontend and http-pretend-keepalive
in a backend. httpclose used to take priority over keepalive, thus voiding
its effect. This change ensures that when both are combined, keepalive is
still announced to the server while close is announced to the client.
(cherry picked from commit 2be7ec90fa9caf66294f446423bbab2d00db9004)
Some broken browsers still happen to send a CRLF after a POST. Those which
send a CRLF in a second packet have it queued into the system's buffers,
which causes an RST to be emitted by some systems upon close of the response
(eg: Linux). The client may then receive the RST without the last response
segments, resulting in a truncated response.
This change leaves request polling enabled on a POST so that we can flush
any late data from the request buffers.
A more complete workaround would consist in reading from the request for a
long time, until we get confirmation that the close has been ACKed. This
is much more complex and should only be studied for newer versions.
(cherry picked from commit 12e316af4f0245fde12dbc224ebe33c8fea806b2)
This patch addresses exactly the same issues as the previous one, but
for responses this time. It also introduces implicit support for the
Set-Cookie2 header, for which there's almost nothing specific to do
since it is a clean header. This one allows multiple cookies in a
same header, by respecting the HTTP messaging semantics.
The new parser has been tested with insertion, rewrite, passive,
removal, prefixing and captures, and it looks OK. It's still able
to rewrite (or delete) multiple cookies at once. Just as with the
request parser, it tries hard to fix formating of the cookies it
displaces.
This patch too should be backported to 1.4 and possibly to 1.3.
The request cookie parser did not allow spaces to appear in cookie
values nor around the equal sign. The various RFCs on the subject
say different things, some suggesting that a space is allowed after
the equal sign and being worded in a way that lets one believe it
is allowed before too. Some spaces may appear inside values and be
part of the values. The quotes allow delimiters to be embedded in
values. The spaces before and after attributes should be trimmed.
The new parser addresses all those points and has been carefully tested.
It fixes misplaced spaces around equal signs before processing the cookies
or forwarding them. It also tries its best to perform clean removals by
always keeping the delimiter after the value being removed and leaving one
space after it.
The variable inside the parser have been renamed to make the code a lot
more understandable, and one multi-function pointer has been eliminated.
Since this patch fixes real possible issues, it should be backported to 1.4
and possibly 1.3, since one (single) case of wrong spaces has been reported
in 1.3.
The code handling the Set-Cookie has not been touched yet.
The header parser has a bug which causes commas to be matched within
quotes while it was not expected. The way the code was written could
make one think it was OK. The resulting effect is that the following
config would use the second IP address instead of the third when facing
this request :
source 0.0.0.0 usesrc hdr_ip(X-Forwarded-For,2)
GET / HTTP/1.0
X-Forwarded-for: "127.0.0.1, 127.0.0.2", 127.0.0.3
This fix must be backported to 1.4 and 1.3.
Fix 4fe4190278 was a bit too strong. It
has caused some chunked-encoded responses to be truncated when a recv()
call could return multiple chunks followed by a close. The reason is
that when a chunk is parsed, only its contents are scheduled to be
forwarded. Thus, the reader sees auto_close+shutr and sets shutw_now.
The sender in turn sends the last scheduled data and does shutw().
Another nasty effect is that it has reduced the keep-alive rate. If
a response did not completely fit into the buffer, then the auto_close
bit was left on and the sender would close upon completion.
The fix consists in not making use of auto_close when chunked encoding
is used nor when keep-alive is used, which makes sense. However it is
maintained on error processing.
Thanks to Cyril Bont for reporting the issue early.
While it's usually desired to wait for a server response even
when the client closes its request channel, it can be problematic
with long polling requests. In order to let the server decide what
to do in such a case, if option abortonclose is set, we simply
forward the shutdown to the server. That way, it can decide to
take the appropriate action. Most servers will still process the
request, while some will probably want to abort.
Obviously, this only works as long as the client has not sent
another pipelined request over the same connection.
(was commit 0e25d86da49827ff6aa3c94132c01292b5ba4854 in 1.4)
Having a single tracking pointer for both frontend and backend counters
does not work. Instead let's have one for each. The keyword has changed
to "track-be-counters" and "track-fe-counters", and the ACL "trk_*"
changed to "trkfe_*" and "trkbe_*".
This patch adds support for the following session counters :
- http_req_cnt : HTTP request count
- http_req_rate: HTTP request rate
- http_err_cnt : HTTP request error count
- http_err_rate: HTTP request error rate
The equivalent ACLs have been added to check the tracked counters
for the current session or the counters of the current source.
When resetting a session's request analysers, we must take them from the
listener, not from the frontend. At the moment there is no difference
but this might change.
Till now, the frontend relied on the backend's options for INDEPSTR,
while at the time of accept, the frontend and backend are the same.
So we now use the frontend's pointer instead of the backend and we
don't have any dependency on the backend anymore in the frontend's
accept code.
The conn_retries attribute is now assigned when switching from SI_ST_INI
to SI_ST_REQ. This eliminates one of the last dependencies on the backend
in the frontend's accept() function.
The conn_retries still lies in the session and its initialization depends
on the backend when it may not yet be known. Let's first move it to the
stream interface.
It was particularly embarrassing that the server timeout was assigned
to buffers during an accept() just to be potentially changed later in
case of a use_backend rule. The frontend side has nothing to do with
server timeouts.
Now we initialize them right after the connect() succeeds. Later this
should change for a unique stream-interface timeout setting only.
The connection timeout stored in the buffer has not been used since the
stream interface were introduced. Let's get rid of it as it's one of the
things that complicate factoring of the accept() functions.
The 'client.c' file now only contained frontend-specific functions,
so it has naturally be renamed 'frontend.c'. Same for client.h. This
has also been an opportunity to remove some cross references from
files that should not have depended on it.
In the end, this file should contain a protocol-agnostic accept()
code, which would initialize a session, task, etc... based on an
accept() from a lower layer. Right now there are still references
to TCP.
By using msg->sol as the beginning of a message, wrong messages were
displayed in debug mode when they were truncated on the last line,
because msg->sol points to the beginning of the last line. Use
data+msg->som instead.
This would only be wrong when the server has not completely responded yet.
Fix two other occurrences of wrong rsp<->sl associations which were harmless
but wrong anyway.
Latest BF_READ_ATTACHED fix has unveiled a nice issue with the way
HTTP requests and responses are forwarded. The case where the request
aborts after the response has responded (POST with early response)
forgot to re-enable auto-close on the response. In fact it still
worked thanks to a side effect as long as BF_READ_ATTACHED was there
to force the states to be resynced (and the flags). Since last fix,
the missing auto-close causes CLOSE_WAIT connections when the client
aborts too late during a data transfer.
The right fix consists in considering the situation where the client
experiences an error and to explicitly abort the transfer. There is
no need to wake the response analysers up for that since they'd have
no added value and the analysers flags are cleared. However for a
future usage, that might help (eg: stickiness, ...).
This fix should be backported to 1.4 if the previous one is backported
too. After all the non-reg tests, the risks to see a problem arise
without both patches seems low, and both patches touch sensible areas
of the code. So there's no hurry.
Both dispatch and http_proxy modes were broken since 1.4-dev5 when
the adjustment of server health based on response codes was introduced.
In fact, in these modes, s->srv == NULL. The result is a plain segfault.
It should have been noted critical, but the fact that it remained 6
months without being noticed indicates that almost nobody uses these
modes anymore. Also, the crash is immediate upon first request.
Further versions should not be affected anymore since it's planned to
have a dummy server instead of these annoying NULL pointers.
It is now possible to stick on an IP address found in a HTTP header. Right
now only the last occurrence of the header can be used, which is generally
enough for most uses. Also, the header extraction rule only knows how to
convert the header to IP. Later it will be usable as a plain string with
an implicit conversion, and the syntax will not change.
Networks patterns loaded from files for longest match ACL testing
will now be arranged into a prefix tree. This is possible thanks to
the new prefix features in ebtree v6.0. Longest match testing is
slightly slower than exact data maching. However, the measured impact
of running at 42000 requests per second and testing whether the IP
address found in a header belongs to a list of 52000 networks or
not is 3% CPU (increase from 66% to 69%). This is low enough to
permit true geolocation based on huge tables.
Now if some ACL patterns are loaded from a file and the operation is
an exact string match, the data will be arranged in a tree, yielding
a significant performance boost on large data sets. Note that this
only works when case is sensitive.
A new dedicated function, acl_lookup_str(), has been created for this
matching. It is called for every possible input data to test and it
looks the tree up for the data. Since the keywords are loosely typed,
we would have had to add a new columns to all keywords to adjust the
function depending on the type. Instead, we just compare on the match
function. We call acl_lookup_str() when we could use acl_match_str().
The tree lookup is performed first, then the remaining patterns are
attempted if the tree returned nothing.
A quick test shows that when matching a header against a list of 52000
network names, haproxy uses 68% of one core on a core2-duo 3.2 GHz at
42000 requests per second, versus 66% without any rule, which means
only a 2% CPU increase for 52000 rules. Doing the same test without
the tree leads to 100% CPU at 6900 requests/s. Also it was possible
to run the same test at full speed with about 50 sets of 52000 rules
without any measurable performance drop.
When trying to display an invalid request or response we received,
we must at least check that we have identified something looking
like a start of message, otherwise we can dereference a NULL pointer.
This is used to disable persistence depending on some conditions (for
example using an ACL matching static files or a specific User-Agent).
You can see it as a complement to "force-persist".
In the configuration file, the force-persist/ignore-persist declaration
order define the rules priority.
Used with the "appsesion" keyword, it can also help reducing memory usage,
as the session won't be hashed the persistence is ignored.
I met a strange behaviour with appsession.
I firstly thought this was a regression due to one of my previous patch
but after testing with a 1.3.15.12 version, I also could reproduce it.
To illustrate, the configuration contains :
appsession PHPSESSID len 32 timeout 1h
Then I call a short PHP script containing :
setcookie("P", "should not match")
When calling this script thru haproxy, the cookie "P" matches the appsession rule :
Dumping hashtable 0x11f05c8
table[1572]: should+not+match
Shouldn't it be ignored ?
If you confirm, I'll send a patch for 1.3 and 1.4 branches to check that the
cookie length is equal to the appsession name length.
This is due to the comparison length, where the cookie length is took into
account instead of the appsession name length. Using the appsession name
length would allow ASPSESSIONIDXXX (+ check that memcmp won't go after the
buffer size).
Also, while testing, I noticed that HEAD requests where not available for
URIs containing the appsession parameter. 1.4.3 patch fixes an horrible
segfault I missed in a previous patch when appsession is not in the
configuration and HAProxy is compiled with DEBUG_HASH.
Some servers do not completely conform with RFC2616 requirements for
keep-alive when they receive a request with "Connection: close". More
specifically, they don't bother using chunked encoding, so the client
never knows whether the response is complete or not. One immediately
visible effect is that haproxy cannot maintain client connections alive.
The second issue is that truncated responses may be cached on clients
in case of network error or timeout.
scar Fras Barranco reported this issue on Tomcat 6.0.20, and
Patrik Nilsson with Jetty 6.1.21.
Cyril Bont proposed this smart idea of pretending we run keep-alive
with the server and closing it at the last moment as is already done
with option forceclose. The advantage is that we only change one
emitted header but not the overall behaviour.
Since some servers such as nginx are able to close the connection
very quickly and save network packets when they're aware of the
close negociation in advance, we don't enable this behaviour by
default.
"option http-pretend-keepalive" will have to be used for that, in
conjunction with "option http-server-close".
Using get_ip_from_hdr2() we can look for occurrence #X or #-X and
extract the IP it contains. This is typically designed for use with
the X-Forwarded-For header.
Using "usesrc hdr_ip(name,occ)", it becomes possible to use the IP address
found in <name>, and possibly specify occurrence number <occ>, as the
source to connect to a server. This is possible both in a server and in
a backend's source statement. This is typically used to use the source
IP previously set by a upstream proxy.
Bernhard Krieger reported truncated HTTP responses in presence of some
specific chunk-encoded data, and kindly offered complete traces of the
issue which made it easy to reproduce it.
Those traces showed that the chunks were of exactly 8192 bytes, chunk
size and CRLF included, which was exactly half the size of the buffer.
In this situation, the function http_chunk_skip_crlf() could erroneously
try to parse a CRLF after the chunk believing there were more data
pending, because the number of bytes present in the buffer was considered
instead of the number of remaining bytes to be parsed.
Those two codes can be triggered on demand by client requests.
We must not fail a server on them.
Ideally we should ignore a certain amount of status codes which do
not indicate life nor death.
Hi Willy,
Please find a small patch to prevent haproxy segfaulting when logging captured headers in CLF format.
Example config to reproduce the bug :
listen test :10080
log 127.0.0.1 local7 debug err
mode http
option httplog clf
capture request header NonExistantHeader len 16
--
Cyril Bont
In case of pipelined requests, if the client aborts before reading response
N-1, haproxy waits forever for the data to leave the buffer before parsing
the next response.
Often we need to understand why some transfers were aborted or what
constitutes server response errors. With those two counters, it is
now possible to detect an unexpected transfer abort during a data
phase (eg: too short HTTP response), and to know what part of the
server response errors may in fact be assigned to aborted transfers.
A copy-paste typo and a missing check were causing the logs to
report "PR" instead of "SD" when a server closes before sending
full data. Also, the log would erroneously report 502 while in
fact the correct response will already have been transmitted.
The bounce realign function was algorithmically good but as expected
it was not cache-friendly. Using it with large requests caused so many
cache thrashing that the function itself could drain 70% of the total
CPU time for only 0.5% of the calls !
Revert back to a standard memcpy() using a specially allocated swap
buffer. We're now back to 2M req/s on pipelined requests.
It is wrong to merge FE and BE stats for a proxy because when we consult a
BE's stats, it reflects the FE's stats eventhough the BE has received no
traffic. The most common example happens with listen instances, where the
backend gets credited for all the trafic even when a use_backend rule makes
use of another backend.
The trash buffer may now be smaller than a buffer because we can tune
it at run time. This causes a risk when we're trying to use it as a
temporary buffer to realign unaligned requests, because we may have to
put up to a full buffer into it.
Instead of doing a double copy, we're now relying on an open-coded
bouncing copy algorithm. The principle is that we move one byte at
a time to its final place, and if that place also holds a byte, then
we move it too, and so on. We finish when we've moved all the buffer.
It limits the number of memory accesses, but since it proceeds one
byte at a time and with random walk, it's not cache friendly and
should be slower than a double copy. However, it's only used in
extreme situations and the difference will not be noticeable.
It has been extensively tested and works reliably.
The fix below was incomplete :
commit d5fd51c75b
[BUG] http_server_error() must not purge a previous pending response
This can cause parts of responses to be truncated in case of
pipelined requests if the second request generates an error
before the first request is completely flushed.
Pending response data being rejected was still sent, causing inappropriate
error responses in case of error while parsing a response header. We must
purge pending data from the response buffer that were not scheduled to be
sent (l - send_max).
Now we establish the tunnel only once the status 200 reponse is
received. That way we can still support an authentication request
in response to a CONNECT, then a client's authentication response.
A 101 response is accompanied with an Upgrade header indicating
a new protocol that is spoken on the connection after the exchange
completes. At least we should switch to tunnel mode after such a
response.
I'm not sure if the fix is correct:
- if (req_acl->cond)
- ret = acl_exec_cond(req_acl->cond, px, s, txn, ACL_DIR_REQ);
+ if (!req_acl->cond)
+ continue;
Doesn't it ignore rules with no condition attached? I think that the
proper solution would be the following.
