A problem was reported recently by some users of programs compiled
with Go 1.5 which by default blocks all signals before executing
processes, resulting in haproxy not receiving SIGUSR1 or even SIGTERM.
This program mimmicks this behaviour to make it easier to run tests.
It also displays the current signal mask. A simple test consists in
running it through itself.
In C89, "void *" is automatically promoted to any pointer type. Casting
the result of malloc/calloc to the type of the LHS variable is therefore
unneeded.
Most of this patch was built using this Coccinelle patch:
@@
type T;
@@
- (T *)
(\(lua_touserdata\|malloc\|calloc\|SSL_get_app_data\|hlua_checkudata\|lua_newuserdata\)(...))
@@
type T;
T *x;
void *data;
@@
x =
- (T *)
data
@@
type T;
T *x;
T *data;
@@
x =
- (T *)
data
Unfortunately, either Coccinelle or I is too limited to detect situation
where a complex RHS expression is of type "void *" and therefore casting
is not needed. Those cases were manually examined and corrected.
A number of config files were present in the tests/ directory and which
would either test features that are easier to test using more recent files
or test obsolete features. All of them emit tons of useless warnings, and
instead of fixing them, better remove them since they have never been used
in the last 10 years or so.
The remaining files may still emit warnings and require some fixing but
they provide some value for some tests.
Summary:
Added a document for hashing under internal docs explaining
hashing in haproxy along with the results of tests under the test
folder.
These documents together explain the motivation for adding
options for hashing algorithms with the option of enabling or
disabling of avalanche.
Before it was possible to resize the buffers using global.tune.bufsize,
the trash has always been the size of a buffer by design. Unfortunately,
the recent buffer sizing at runtime forgot to adjust the trash, resulting
in it being too short for content rewriting if buffers were enlarged from
the default value.
The bug was encountered in 1.4 so the fix must be backported there.
make_arg_list() builds an array of typed arguments with their values,
that the caller describes how to parse. This will be used to support
multiple arguments for ACLs and patterns, which is currently problematic
and prevents ACLs and patterns from being merged. Up to 7 arguments types
may be enumerated in a single 32-bit word, including their number of
mandatory parts.
At the moment, these files are not used yet, they're only built. Note that
the 4-bit encoding for the type has left only one unused type!
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.
The MySQL check has been revamped to be able to send real MySQL data,
and to avoid Aborted connects on MySQL side.
It is however backward compatible with older version, but it is highly
recommended to use the new mode, by adding "user <username>" on the
"mysql-check" line.
The new check consists in sending two MySQL packet, one Client
Authentication packet, with "haproxy" username (by default), and one
QUIT packet, to correctly close MySQL session. We then parse the Mysql
Handshake Initialisation packet and/or Error packet. It is a basic but
useful test which does not produce error nor aborted connect on the
server.
(cherry picked from commit a1e4dcfe5718311b7653d7dabfad65c005d0439b)
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.
If the prefix is set to "/", it means the user does not want to alter
the original URI, so we don't want to insert a new slash before the
original URI.
(cherry-picked from commit 02a35c74942c1bce762e996698add1270e6a5030)
It is now possible to set or clear a cookie during a redirection. This
is useful for logout pages, or for protecting against some DoSes. Check
the documentation for the options supported by the "redirect" keyword.
(cherry-picked from commit 4af993822e880d8c932f4ad6920db4c9242b0981)
If "drop-query" is present on a "redirect" line using the "prefix" mode,
then the returned Location header will be the request URI without the
query-string. This may be used on some login/logout pages, or when it
must be decided to redirect the user to a non-secure server.
(cherry-picked from commit f2d361ccd73aa16538ce767c766362dd8f0a88fd)
22 regression tests for state machines are managed by the new
file tests/test-fsm.cfg. Check it, they are all documented
inside. Most of the bugs introduced during the FSM extraction
have been found with these tests.
The new "wait_end" acl delays evaluation of the rule (and the next ones)
to the end of the analysis period. This is intented to be used with TCP
content analysis. A rule referencing such an ACL will not match until
the delay is over. An equivalent default ACL "WAIT_END" has been created.
This new keyword matches an dotted version mapped into an integer.
It permits to match an SSL message protocol version just as if it
was an integer, so that it is easy to map ranges, like this :
acl obsolete_ssl req_ssl_ver lt 3
acl correct_ssl req_ssl_ver 3.0-3.1
acl invalid_ssl req_ssl_ver gt 3.1
Both SSLv2 hello messages and SSLv3 messages are supported. The
test tries to be strict enough to avoid being easily fooled. In
particular, it waits for as many bytes as announced in the message
header if this header looks valid (bound to the buffer size).
The same decoder will be usable with minor changes to check the
response messages.
Some people need to inspect contents of TCP requests before
deciding to forward a connection or not. A future extension
of this demand might consist in selecting a server farm
depending on the protocol detected in the request.
For this reason, a new state CL_STINSPECT has been added on
the client side. It is immediately entered upon accept() if
the statement "tcp-request inspect-delay <xxx>" is found in
the frontend configuration. Haproxy will then wait up to
this amount of time trying to find a matching ACL, and will
either accept or reject the connection depending on the
"tcp-request content <action> {if|unless}" rules, where
<action> is either "accept" or "reject".
Note that it only waits that long if no definitive verdict
can be found earlier. That generally implies calling a fetch()
function which does not have enough information to decode
some contents, or a match() function which only finds the
beginning of what it's looking for.
It is only at the ACL level that partial data may be processed
as such, because we need to distinguish between MISS and FAIL
*before* applying the term negation.
Thus it is enough to add "| ACL_PARTIAL" to the last argument
when calling acl_exec_cond() to indicate that we expect
ACL_PAT_MISS to be returned if some data is missing (for
fetch() or match()). This is the only case we may return
this value. For this reason, the ACL check in process_cli()
has become a lot simpler.
A new ACL "req_len" of type "int" has been added. Right now
it is already possible to drop requests which talk too early
(eg: for SMTP) or which don't talk at all (eg: HTTP/SSL).
Also, the acl fetch() functions have been extended in order
to permit reporting of missing data in case of fetch failure,
using the ACL_TEST_F_MAY_CHANGE flag.
The default behaviour is unchanged, and if no rule matches,
the request is accepted.
As a side effect, all layer 7 fetching functions have been
cleaned up so that they now check for the validity of the
layer 7 pointer before dereferencing it.
The wait queues now rely on 4 trees for past, present and future
timers. The computations are cleaner and more reliable. The
wake_expired_tasks function has become simpler. Also, a bug
previously introduced in task_queue() by the first introduction
of eb_trees has been fixed (the eb->key was never updated).
A new "redirect" keyword adds the ability to send an HTTP 301/302/303
redirection to either an absolute location or to a prefix followed by
the original URI. The redirection is conditionned by ACL rules, so it
becomes very easy to move parts of a site to another site using this.
This work was almost entirely done at Exceliance by Emeric Brun.
A test-case has been added in the tests/ directory.
About: [BUG] Flush buffers also where there are exactly 0 bytes left
I'm also attaching a debug patch that helps to trigger this bug.
Without the fix:
# echo -ne "GET /haproxy?stats;csv;norefresh HTTP/1.0\r\n\r\n"|nc 127.0.0.1
801|wc -c
16384
With the fix:
# echo -ne "GET /haproxy?stats;csv;norefresh HTTP/1.0\r\n\r\n"|nc 127.0.0.1
801|wc -c
33089
Best regards,
Krzysztof Oledzki
If we want to support netmasks for IP address hashing,
we will need something better than a pure modulus, otherwise
people with even numbers of servers will get surprizes.
Bob Jenkins is known for his works on hashing, and his site
has a lot of very interesting researches and algorithms for
integer hashing. He also points to the work of Thomas Wang
who has similar findings.
The program here tests their algorithms in order to find one
well suited for IP address hashing.
The new "leastconn" LB algorithm selects the server which has the
least established or pending connections. The weights are considered,
so that a server with a weight of 20 will get twice as many connections
as the server with a weight of 10.
The algorithm respects the minconn/maxconn settings, as well as the
slowstart since it is a dynamic algorithm. It also correctly supports
backup servers (one and all).
It is generally suited for protocols with long sessions (such as remote
terminals and databases), as it will ensure that upon restart, a server
with no connection will take all new ones until its load is balanced
with others.
A test configuration has been added in order to ease regression testing.
In order to offer DoS protection, it may be required to lower the maximum
accepted time to receive a complete HTTP request without affecting the client
timeout. This helps protecting against established connections on which
nothing is sent. The client timeout cannot offer a good protection against
this abuse because it is an inactivity timeout, which means that if the
attacker sends one character every now and then, the timeout will not
trigger. With the HTTP request timeout, no matter what speed the client
types, the request will be aborted if it does not complete in time.
Add the "backlog" parameter to frontends, to give hints to
the system about the approximate listen backlog desired size.
In order to protect against SYN flood attacks, one solution is
to increase the system's SYN backlog size. Depending on the
system, sometimes it is just tunable via a system parameter,
sometimes it is not adjustable at all, and sometimes the system
relies on hints given by the application at the time of the
listen() syscall. By default, HAProxy passes the frontend's
maxconn value to the listen() syscall. On systems which can
make use of this value, it can sometimes be useful to be able
to specify a different value, hence this backlog parameter.
A new "timeout" keyword replaces old "{con|cli|srv}timeout", and
provides the ability to independantly set the following timeouts :
- client
- tarpit
- queue
- connect
- server
- appsession
Additionally, the "clitimeout", "contimeout" and "srvtimeout" values
are supported but deprecated. No warning is emitted yet when they are
used since the option is very new.
Other timeouts should follow soon now.
It is not always handy to manipulate large values exprimed
in milliseconds for timeouts. Also, some values are entered
in seconds (such as the stats refresh interval). This patch
adds support for time units. It knows about 'us', 'ms', 's',
'm', 'h', and 'd'. It automatically converts each value into
the caller's expected unit. Unit-less values are still passed
unchanged.
The unit must be passed as a suffix to the number. For instance:
clitimeout 15m
If any character is not understood, an error is returned.
In order to avoid issues in the future, we want to restrict
the set of allowed characters for identifiers. Starting from
now, only A-Z, a-z, 0-9, '-', '_', '.' and ':' will be allowed
for a proxy, a server or an ACL name.
A test file has been added to check the restriction.
Now we can compute the max place depending on the number of servers,
maximum weight and weight scale. The formula has been stored as a
comment so that it's easy to choose between smooth weight ramp up
and high number of servers. The default scale has been set to 16,
which permits 4000 servers with a granularity of 6% in the worst
case (weight=1).
The default_backend did not work in TCP mode since there was no
header state to assign the backend. This causes much trouble when
configs are created by copy-paste.
The solution was to fix the way the backend is assigned upon accept().
A wrong contimeout assignment was fixed too.
