Edns extensions may be used to negotiate some settings between a DNS
client and a server.
For now we only use it to announce the maximum response payload size accpeted
by HAProxy.
This size can be set through a configuration parameter in the resolvers
section. If not set, it defaults to 512 bytes.
Make it so for each server, instead of specifying a hostname, one can use
a SRV label.
When doing so, haproxy will first resolve the SRV label, then use the
resulting hostnames, as well as port and weight (priority is ignored right
now), to each server using the SRV label.
It is resolved periodically, and any server disappearing from the SRV records
will be removed, and any server appearing will be added, assuming there're
free servers in haproxy.
As DNS servers may not return all IPs in one answer, we want to cache the
previous entries. Those entries are removed when considered obsolete, which
happens when the IP hasn't been returned by the DNS server for a time
defined in the "hold obsolete" parameter of the resolver section. The default
is 30s.
When several stick-tables were configured with several peers sections,
only a part of them could be synchronized: the ones attached to the last
parsed 'peers' section. This was due to the fact that, at least, the peer I/O handler
refered to the wrong peer section list, in fact always the same: the last one parsed.
The fact that the global peer section list was named "struct peers *peers"
lead to this issue. This variable name is dangerous ;).
So this patch renames global 'peers' variable to 'cfg_peers' to ensure that
no such wrong references are still in use, then all the functions wich used
old 'peers' variable have been modified to refer to the correct peer list.
Must be backported to 1.6 and 1.7.
The pool used to log the uri was created with a size of 0 because the
configuration and 'tune.http.logurilen' were parsed too earlier.
The fix consist to postpone the pool_create as it is done for
cookie captures.
Regression introduced with 'MINOR: log: Add logurilen tunable'
We cannot store more than 32K headers in the structure hdr_idx, because
internaly we use signed short integers. To avoid any bugs (due to an integers
overflow), a check has been added on tune.http.maxhdr to be sure to not set a
value greater than 32767 and lower than 1 (because this is a nonsense to set
this parameter to a value <= 0).
The documentation has been updated accordingly.
This patch can be backported in 1.7, 1.6 and 1.5.
This patch is a major upgrade of the internal run-time DNS resolver in
HAProxy and it brings the following 2 main changes:
1. DNS resolution task
Up to now, DNS resolution was triggered by the health check task.
From now, DNS resolution task is autonomous. It is started by HAProxy
right after the scheduler is available and it is woken either when a
network IO occurs for one of its nameserver or when a timeout is
matched.
From now, this means we can enable DNS resolution for a server without
enabling health checking.
2. Introduction of a dns_requester structure
Up to now, DNS resolution was purposely made for resolving server
hostnames.
The idea, is to ensure that any HAProxy internal object should be able
to trigger a DNS resolution. For this purpose, 2 things has to be done:
- clean up the DNS code from the server structure (this was already
quite clean actually) and clean up the server's callbacks from
manipulating too much DNS resolution
- create an agnostic structure which allows linking a DNS resolution
and a requester of any type (using obj_type enum)
3. Manage requesters through queues
Up to now, there was an uniq relationship between a resolution and it's
owner (aka the requester now). It's a shame, because in some cases,
multiple objects may share the same hostname and may benefit from a
resolution being performed by a third party.
This patch introduces the notion of queues, which are basically lists of
either currently running resolution or waiting ones.
The resolutions are now available as a pool, which belongs to the resolvers.
The pool has has a default size of 64 resolutions per resolvers and is
allocated at configuration parsing.
This patch introduces a some re-organisation around the DNS code in
HAProxy.
1. make the dns_* functions less dependent on 'struct server' and 'struct resolution'.
With this in mind, the following changes were performed:
- 'struct dns_options' has been removed from 'struct resolution' (well,
we might need it back at some point later, we'll see)
==> we'll use the 'struct dns_options' from the owner of the resolution
- dns_get_ip_from_response(): takes a 'struct dns_options' instead of
'struct resolution'
==> so the caller can pass its own dns options to get the most
appropriate IP from the response
- dns_process_resolve(): struct dns_option is deduced from new
resolution->requester_type parameter
2. add hostname_dn and hostname_dn_len into struct server
In order to avoid recomputing a server's hostname into its domain name
format (and use a trash buffer to store the result), it is safer to
compute it once at configuration parsing and to store it into the struct
server.
In the mean time, the struct resolution linked to the server doesn't
need anymore to store the hostname in domain name format. A simple
pointer to the server one will make the trick.
The function srv_alloc_dns_resolution() properly manages everything for
us: memory allocation, pointer updates, etc...
3. move resolvers pointer into struct server
This patch makes the pointer to struct dns_resolvers from struct
dns_resolution obsolete.
Purpose is to make the resolution as "neutral" as possible and since the
requester is already linked to the resolvers, then we don't need this
information anymore in the resolution itself.
The default len of request uri in log messages is 1024. In some use
cases, you need to keep the long trail of GET parameters. The only
way to increase this len is to recompile with DEFINE=-DREQURI_LEN=2048.
This commit introduces a tune.http.logurilen configuration directive,
allowing to tune this at runtime.
This option exits every workers when one of the current workers die.
It allows you to monitor the master process in order to relaunch
everything on a failure.
For example it can be used with systemd and Restart=on-failure in a spec
file.
This commit remove the -Ds systemd mode in HAProxy in order to replace
it by a more generic master worker system. It aims to replace entirely
the systemd wrapper in the near future.
The master worker mode implements a new way of managing HAProxy
processes. The master is in charge of parsing the configuration
file and is responsible for spawning child processes.
The master worker mode can be invoked by using the -W flag. It can be
used either in background mode (-D) or foreground mode. When used in
background mode, the master will fork to daemonize.
In master worker background mode, chroot, setuid and setgid are done in
each child rather than in the master process, because the master process
will still need access to filesystem to reload the configuration.
When HAProxy is running with multiple processes and some listeners
arebound to processes, the unused sockets were not closed in the other
processes. The aim was to be able to send those listening sockets using
the -x option.
However to ensure the previous behavior which was to close those
sockets, we provided the "no-unused-socket" global option.
This patch changes this behavior, it will close unused sockets which are
not in the same process as an expose-fd socket, making the
"no-unused-socket" option useless.
The "no-unused-socket" option was removed in this patch.
This patch adds a new stats socket command to modify server
FQDNs at run time.
Its syntax:
set server <backend>/<server> fqdn <FQDN>
This patch also adds FQDNs to server state file at the end
of each line for backward compatibility ("-" if not present).
This patch makes backend sections support 'server-template' new keyword.
Such 'server-template' objects are parsed similarly to a 'server' object
by parse_server() function, but its first arguments are as follows:
server-template <ID prefix> <nb | range> <ip | fqdn>:<port> ...
The remaining arguments are the same as for 'server' lines.
With such server template declarations, servers may be allocated with IDs
built from <ID prefix> and <nb | range> arguments.
For instance declaring:
server-template foo 1-5 google.com:80 ...
or
server-template foo 5 google.com:80 ...
would be equivalent to declare:
server foo1 google.com:80 ...
server foo2 google.com:80 ...
server foo3 google.com:80 ...
server foo4 google.com:80 ...
server foo5 google.com:80 ...
When running with multiple process, if some proxies are just assigned
to some processes, the other processes will just close the file descriptors
for the listening sockets. However, we may still have to provide those
sockets when reloading, so instead we just try hard to pretend those proxies
are dead, while keeping the sockets opened.
A new global option, no-reused-socket", has been added, to restore the old
behavior of closing the sockets not bound to this process.
The error doesn't prevent checking for other errors after an invalid
character was detected in an ACL name. Better quit ASAP to avoid risking
to emit garbled and confusing error messages if something else fails on
the same line.
This should be backported to 1.7, 1.6 and 1.5.
There is a silly case where a loop is not detected in tracked servers lists:
when a server tracks itself.
Ex:
server srv1 127.0.0.1:8000 track srv1
Well, this never happens and this does not prevent haproxy from working.
But with this next following configuration:
server srv1 127.0.0.1:8000 track srv2
server srv2 127.0.0.1:8000 track srv2
server srv3 127.0.0.1:8000 track srv2
the code in charge of detecting such loops never returns (without any error message).
haproxy becomes stuck in an infinite loop because of this statement found
in check_config_validity():
for (loop = srv->track; loop && loop != newsrv; loop = loop->track);
Again, such a configuration is never accidentally used I guess.
This latter example seems silly, but as several 'default-server' directives may be used
in the same proxy section, and as 'default-server' settings are not resetted each a
new 'default-server' line is created, it will match the following configuration, in the future,
when 'track' setting will be supported by 'default-server':
default-server track srv3
server srv1 127.0.0.1:8000
server srv2 127.0.0.1:8000
.
.
.
default-server check
server srv3 127.0.0.1:8000
(cherry picked from commit 6528fc93d3c065fdac841f24e55cfe9674a67414)
This adds a new "dynamic" keyword for the cookie option. If set, a cookie
will be generated for each server (assuming one isn't already provided on
the "server" line), from the IP of the server, the TCP port, and a secret
key provided. To provide the secret key, a new keyword as been added,
"dynamic-cookie-key", for backends.
Example :
backend bk_web
balance roundrobin
dynamic-cookie-key "bla"
cookie WEBSRV insert dynamic
server s1 127.0.0.1:80 check
server s2 192.168.56.1:80 check
This is a first step to be able to dynamically add and remove servers,
without modifying the configuration file, and still have all the load
balancers redirect the traffic to the right server.
Provide a way to generate session cookies, based on the IP address of the
server, the TCP port, and a secret key provided.
Surprizingly, http-request, http-response, block, redirect, and capture
rules did not cause a warning to be emitted when used in a TCP proxy, so
let's fix this.
This patch may be backported to older versions as it helps spotting
configuration issues.
Adrian Fitzpatrick reported that since commit f51658d ("MEDIUM: config:
relax use_backend check to make the condition optional"), typos like "of"
instead of "if" on use_backend rules are not properly detected. The reason
is that the parser only checks for "if" or "unless" otherwise it considers
there's no keyword, making the rule inconditional.
This patch fixes it. It may reveal some rare config bugs for some people,
but will not affect valid configurations.
This fix must be backported to 1.7, 1.6 and 1.5.
The previous version used an O(number of proxies)^2 algo to get the sum of
the number of maxconns of frontends which reference a backend at least once.
This new version adds the frontend's maxconn number to the backend's
struct proxy member 'tot_fe_maxconn' when the backend name is resolved
for switching rules or default_backend statment. At the end, the final
backend's fullconn is computed looping only one time for all on proxies O(n).
The load of a configuration using a large amount of backends (10 thousands)
without configured fullconn was reduced from several minutes to few seconds.
http-reuse should normally not be used in conjunction with the proxy
protocol or with "usesrc clientip". While there's nothing fundamentally
wrong with this, whenever these options are used, the server expects the
IP address to be the source address for all requests, which doesn't make
sense with http-reuse.
It is important to defined analyzers (AN_REQ_* and AN_RES_*) in the same order
they are evaluated in process_stream. This order is really important because
during analyzers evaluation, we run them in the order of the lower bit to the
higher one. This way, when an analyzer adds/removes another one during its
evaluation, we know if it is located before or after it. So, when it adds an
analyzer which is located before it, we can switch to it immediately, even if it
has already been called once but removed since.
With the time, and introduction of new analyzers, this order was broken up. the
main problems come from the filter analyzers. We used values not related with
their evaluation order. Furthermore, we used same values for request and response
analyzers.
So, to fix the bug, filter analyzers have been splitted in 2 distinct lists to
have different analyzers for the request channel than those for the response
channel. And of course, we have moved them to the right place.
Some other analyzers have been reordered to respect the evaluation order:
* AN_REQ_HTTP_TARPIT has been moved just before AN_REQ_SRV_RULES
* AN_REQ_PRST_RDP_COOKIE has been moved just before AN_REQ_STICKING_RULES
* AN_RES_STORE_RULES has been moved just after AN_RES_WAIT_HTTP
Note today we have 29 analyzers, all stored into a 32 bits bitfield. So we can
still add 4 more analyzers before having a problem. A good way to fend off the
problem for a while could be to have a different bitfield for request and
response analyzers.
[wt: all of this must be backported to 1.7, and part of it must be backported
to 1.6 and 1.5]
Now we can simply check the transport layer at run time and decide
whether or not to initialize or destroy these entries. This removes
other ifdefs and includes from cfgparse.c, haproxy.c and hlua.c.
Now we exclusively use xprt_get(XPRT_RAW) instead of &raw_sock or
xprt_get(XPRT_SSL) for &ssl_sock. This removes a bunch of #ifdef and
include spread over a number of location including backend, cfgparse,
checks, cli, hlua, log, server and session.
Instead of hard-coding all SSL destruction in cfgparse.c and haproxy.c,
we now register this new function as the transport layer's destroy_bind_conf()
and call it only when defined. This removes some non-obvious SSL-specific
code and #ifdefs from cfgparse.c and haproxy.c
Instead of hard-coding all SSL preparation in cfgparse.c, we now register
this new function as the transport layer's prepare_bind_conf() and call it
only when definied. This removes some non-obvious SSL-specific code from
cfgparse.c as well as a #ifdef.
Most of the SSL functions used to have a proxy argument which was mostly
used to be able to emit clean errors using Alert(). First, many of them
were converted to memprintf() and don't require this pointer anymore.
Second, the rare which still need it also have either a bind_conf argument
or a server argument, both of which carry a pointer to the relevant proxy.
So let's now get rid of it, it needlessly complicates the API and certain
functions already have many arguments.
Historically, all listeners have a pointer to the frontend. But since
the introduction of SSL, we now have an intermediary layer called
bind_conf corresponding to a "bind" line. It makes no sense to have
the frontend on each listener given that it's the same for all
listeners belonging to a same bind_conf. Also certain parts like
SSL can only operate on bind_conf and need the frontend.
This patch fixes this by moving the frontend pointer from the listener
to the bind_conf. The extra indirection is quite cheap given and the
places were this is used are very scarce.
A mistake was made when the socket layer was cut into proto and
transport, the transport was attached to the listener while all
listeners in a single "bind" line always have exactly the same
transport. It doesn't seem obvious but this is the reason why there
are so many #ifdefs USE_OPENSSL in cfgparse : a lot of operations
have to be open-coded because cfgparse only manipulates bind_conf
and we don't have the information of the transport layer here.
Very little code makes use of the transport layer, mainly session
setup and log. These places can afford an extra pointer indirection
(the listener points to the bind_conf). This change is thus very small,
it saves a little bit of memory (8B per listener) and makes the code
more flexible.
ssl_sock functions don't mark pointers as NULL after freeing them. So
if a "bind" line specifies some SSL settings without the "ssl" keyword,
they will get freed at the end of check_config_validity(), then freed
a second time on exit. Simply mark the pointers as NULL to fix this.
This fix needs to be backported to 1.7 and 1.6.
This finishes to clean up the zlib-specific parts. It also unbreaks recent
commit b97c6fb ("CLEANUP: compression: use the build options list to report
the algos") which broke USE_ZLIB due to MAXWBITS not being defined anymore
in haproxy.c.
The following keywords were still parsed in cfgparse and were moved
to ssl_sock to remove some #ifdefs :
"tune.ssl.cachesize", "tune.ssl.default-dh-param", "tune.ssl.force-private-cache",
"tune.ssl.lifetime", "tune.ssl.maxrecord", "tune.ssl.ssl-ctx-cache-size".
It's worth mentionning that some of them used to have incorrect sign
checks possibly resulting in some negative values being used. All of
them are now checked for being positive.
This removes 2 #ifdefs and makes the code much cleaner. The controls
are still there and the two parsers have been merged into a single
function ssl_parse_global_ca_crt_base().
It's worth noting that there's still a check to prevent a change when
the value was already specified. This test seems useless and possibly
counter-productive, it may have to be revisited later, but for now it
was implemented identically.
We already had alertif_too_many_args{,_idx}(), but these ones are
specifically designed for use in cfgparse. Outside of it we're
trying to avoid calling Alert() all the time so we need an
equivalent using a pointer to an error message.
These new functions called too_many_args{,_idx)() do exactly this.
They don't take the file name nor the line number which they have
no use for but instead they take an optional pointer to an error
message and the pointer to the error code is optional as well.
With (NULL, NULL) they'll simply check the validity and return a
verdict. They are quite convenient for use in isolated keyword
parsers.
These two new functions as well as the previous ones have all been
exported.
There's no more reason to keep tcp rules processing inside proto_tcp.c
given that there is nothing in common there except these 3 letters : tcp.
The tcp rules are in fact connection, session and content processing rules.
Let's move them to "tcp-rules" and let them live their life there.
There are 8 functions each repeating what another does and adding one
extra test. We used to have some copy-paste issues in the past due to
this. Instead we now make them simply rely on the previous one and add
the final test. It's much better and much safer. The functions could
be moved to inlines but they're used at a few other locations only,
it didn't make much sense in the end.
We used to have 3 types of counters with a huge overlap :
- listener counters : stats collected for each bind line
- proxy counters : union of the frontend and backend counters
- server counters : stats collected per server
It happens that quite a good part was common between listeners and
proxies due to the frontend counters being updated at the two locations,
and that similarly the server and proxy counters were overlapping and
being updated together.
This patch cleans this up to propose only two types of counters :
- fe_counters: used by frontends and listeners, related to
incoming connections activity
- be_counters: used by backends and servers, related to outgoing
connections activity
This allowed to remove some non-sensical counters from both parts. For
frontends, the following entries were removed :
cum_lbconn, last_sess, nbpend_max, failed_conns, failed_resp,
retries, redispatches, q_time, c_time, d_time, t_time
For backends, this ones was removed : intercepted_req.
While doing this it was discovered that we used to incorrectly report
intercepted_req for backends in the HTML stats, which was always zero
since it's never updated.
Also it revealed a few inconsistencies (which were not fixed as they
are harmless). For example, backends count connections (cum_conn)
instead of sessions while servers count sessions and not connections.
Over the long term, some extra cleanups may be performed by having
some counters update functions touching both the server and backend
at the same time, as well as both the frontend and listener, to
ensure that all sides have all their stats properly filled. The stats
dump will also be able to factor the dump functions by counter types.
The function log format emit its own error message using Alert(). This
patch replaces this behavior and uses the standard HAProxy error system
(with memprintf).
The benefits are:
- cleaning the log system
- the logformat can ignore the caller (actually the caller must set
a flag designing the caller function).
- Make the usage of the logformat function easy for future components.