This implements the feature discussed in the earlier thread of killing
connections on backup servers when a non-backup server comes back up. For
example, you can use this to route to a mysql master & slave and ensure
clients don't stay on the slave after the master goes from down->up. I've done
some minimal testing and it seems to work.
[WT: added session flag & doc, moved the killing after logging the server UP,
and ensured that the new server is really usable]
httponly This option tells haproxy to add an "HttpOnly" cookie attribute
when a cookie is inserted. This attribute is used so that a
user agent doesn't share the cookie with non-HTTP components.
Please check RFC6265 for more information on this attribute.
secure This option tells haproxy to add a "Secure" cookie attribute when
a cookie is inserted. This attribute is used so that a user agent
never emits this cookie over non-secure channels, which means
that a cookie learned with this flag will be presented only over
SSL/TLS connections. Please check RFC6265 for more information on
this attribute.
This one was already taken care of in proxy_cfg_ensure_no_http(), so if a
cookie is presented in a TCP backend, we got two warnings.
This can be backported to 1.4 since it's been this way for 2 years (although not dramatic).
Cookies were mixed with many other options while they're not used as options.
Move them to a dedicated bitmask (ck_opts). This has released 7 flags in the
proxy options and leaves some room for new proxy flags.
Option httplog needs to be checked only once the proxy has been validated,
so that its final mode (tcp/http) can be used. Also we need to check for
httplog before checking the log format, so that we can report a warning
about this specific option and not about the format it implies.
The listener struct is now aware of the socket layer to use upon accept().
At the moment, only sock_raw is supported so this patch should not change
anything.
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.
Tunnel timeouts are used when TCP connections are forwarded, or
when forwarding upgraded HTTP connections (WebSocket) as well as
CONNECT requests to proxies.
This timeout allows long-lived sessions to be supported without
having to set large timeouts to normal requests.
Instead of hard-coding sock_raw in connect_server(), we set this socket
operation at config parsing time. Right now, only servers and peers have
it. Proxies are still hard-coded as sock_raw. This will be needed for
future work on SSL which requires a different socket layer.
All keywords registered using a cfg_kw_list now make use of the new error reporting
framework. This allows easier and more precise error reporting without having to
deal with complex buffer allocation issues.
This is mainly a massive renaming in the code to get it in line with the
calling convention. Next patch will rename a few files to complete this
operation.
All parsing errors were known but impossible to return. Now by making use
of memprintf(), we're able to build meaningful error messages that the
caller can display.
Patterns were using a bitmask to indicate if request or response was desired
in fetch functions and keywords. ACLs were using a bitmask in fetch keywords
and a single bit in fetch functions. ACLs were also using an ACL_PARTIAL bit
in fetch functions indicating that a non-final fetch was performed, which was
an abuse of the existing direction flag.
The change now consists in using :
- a capabilities field for fetch keywords => SMP_CAP_REQ/RES to indicate
if a keyword supports requests, responses, both, etc...
- an option field for fetch functions to indicate what the caller expects
(request/response, final/non-final)
The ACL_PARTIAL bit was reversed to get SMP_OPT_FINAL as it's more explicit
to know we're working on a final buffer than on a non-final one.
ACL_DIR_* were removed, as well as PATTERN_FETCH_*. L4 fetches were improved
to support being called on responses too since they're still available.
The <dir> field of all fetch functions was changed to <opt> which is now
unsigned.
The patch is large but mostly made of cosmetic changes to accomodate this, as
almost no logic change happened.
The Unique ID, is an ID generated with several informations. You can use
a log-format string to customize it, with the "unique-id-format" keyword,
and insert it in the request header, with the "unique-id-header" keyword.
* logformat functions now take a format linked list as argument
* build_logline() build a logline using a format linked list
* rename LOG_* by LOG_FMT_* in enum
* improve error management in build_logline()
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.
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.
The principle behind this load balancing algorithm was first imagined
and modeled by Steen Larsen then iteratively refined through several
work sessions until it would totally address its original goal.
The purpose of this algorithm is to always use the smallest number of
servers so that extra servers can be powered off during non-intensive
hours. Additional tools may be used to do that work, possibly by
locally monitoring the servers' activity.
The first server with available connection slots receives the connection.
The servers are choosen from the lowest numeric identifier to the highest
(see server parameter "id"), which defaults to the server's position in
the farm. Once a server reaches its maxconn value, the next server is used.
It does not make sense to use this algorithm without setting maxconn. Note
that it can however make sense to use minconn so that servers are not used
at full load before starting new servers, and so that introduction of new
servers requires a progressively increasing load (the number of servers
would more or less follow the square root of the load until maxconn is
reached). This algorithm ignores the server weight, and is more beneficial
to long sessions such as RDP or IMAP than HTTP, though it can be useful
there too.
parse_logformat_string: parse the string, detect the type: text,
separator or variable
parse_logformat_var: dectect variable name
parse_logformat_var_args: parse arguments and flags
add_to_logformat_list: add to the logformat linked list
When checking a configuration file using "-c -f xxx", sometimes it is
reported that a config is valid while it will later fail (eg: no enabled
listener). Instead, let's improve the return values :
- return 0 if config is 100% OK
- return 1 if config has errors
- return 2 if config is OK but no listener nor peer is enabled
If the local host is not found as a peer in a "peers" section, we have a
double free, and possibly a use-after-free because the peers section is
freed since it's aliased as the table's name.
In a config where server "s1" is marked disabled and "s2" tracks "s1",
s2 appears disabled on the stats but is still inserted into the LB farm
because the tracking is resolved too late in the configuration process.
We now resolve tracked servers before building LB maps and we also mark
the tracking server in maintenance mode, which previously was not done,
causing half of the issue.
Last point is that we also protect srv_is_usable() against electing a
server marked for maintenance. This is not absolutely needed but is a
safe choice and makes a lot of sense.
This fix must be backported to 1.4.
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 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.
Up to now, if a cookie value was specified on a server when the proxy was
in TCP mode, it would cause a fatal error. Now we only report a warning,
since the cookie will be ignored. This makes it easier to generate configs
from scripts.
When reading the code, the "tracked" member of a server makes one
think the server is tracked while it's the opposite, it's a pointer
to the server being tracked. This is particularly true in constructs
such as :
if (srv->tracked) {
Since it's the second time I get caught misunderstanding it, let's
rename it to "track" to avoid the confusion.
Baptiste Assmann reported that a config where a non-existing peers
section is referenced by a stick-table causes a segfault after displaying
the error. This is caused by the freeing of the peers. Setting it to NULL
after displaying the error fixes the issue.
For a long time, the max number of headers was taken as a part of the buffer
size. Since the header size can be configured at runtime, it does not make
much sense anymore.
Nothing was making it necessary to have a static value, so let's turn this into
a tunable with a default value of 101 which equals what was previously used.
It makes no sense to have one pointer to the hdr_idx pool in each proxy
struct since these pools do not depend on the proxy. Let's have a common
pool instead as it is already the case for other types.
By default, pipes are the default size for the system. But sometimes when
using TCP splicing, it can improve performance to increase pipe sizes,
especially if it is suspected that pipes are not filled and that many
calls to splice() are performed. This has an impact on the kernel's
memory footprint, so this must not be changed if impacts are not understood.
If a peers section has no peer named as the local peer, we must destroy
it, otherwise a NULL peer frontend remains in the lists and a segfault
can happen upon a soft restart.
We also now report the missing peer name in order to help troubleshooting.
Peers' frontends must have logging disabled by default, which was not
the case, so logs were randomly emitted upon restart, sometimes causing
a new process to fail to replace the old one.
This made sense a long time ago but since the maxconn is dynamically
computed from the tracking tables, it does not make any sense anymore
and will harm future changes.
This one enforces a per-process connection rate limit, regardless of what
may be set per frontend. It can be a way to limit the CPU usage of a process
being severely attacked.
The side effect is that the global process connection rate is now measured
for each incoming connection, so it will be possible to report it.
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.
Manoj Kumar reported a case where haproxy would crash upon start-up. The
cause was an "http-check expect" statement declared in the defaults section,
which caused a NULL regex to be used during the check. This statement is not
allowed in defaults sections precisely because this requires saving a copy
of the regex in the default proxy. But the check was not made to prevent it
from being declared there, hence the issue.
Instead of adding code to detect its abnormal use, we decided to implement
it. It was not that much complex because the expect_str part was not used
with regexes, so it could hold the string form of the regex in order to
compile it again for every backend (there's no way to clone regexes).
This patch has been tested and works. So it's both a bugfix and a minor
feature enhancement.
It should be backported to 1.4 though it's not critical since the config
was not supposed to be supported.
