post_section_px_cleanup(), which was implemented in abcc73830
("MEDIUM: proxy: register a post-section cleanup function"), is called
for the current section no matter if the parsing was aborted due to
a fatal error. In this case, the curproxy pointer may point to NULL,
yet post_section_px_cleanup() assumes curproxy pointer is always valid,
which could lead to NULL-deref.
For instance, the config below will cause SEGFAULT:
listen toto titi
To fix the issue, let's simply consider that the curproxy pointer may
be NULL in post_section_px_cleanup(), in which case we skip the cleanup
for the curproxy since there is nothing we can do.
No backport needed
75e480d10 ("MEDIUM: stats: avoid 1 indirection by storing the shared
stats directly in counters struct") took care of renaming
counters_fe_shared_init() but we forgot counters_be_shared_init().
Let's fix that for consistency
Following commit 75e480d10 ("MEDIUM: stats: avoid 1 indirection by storing
the shared stats directly in counters struct"), in order to minimize the
impact of the recent sharded counters work, we try to push things a bit
further in this patch by storing and using "fast" pointers at the session
and stream levels when available to avoid costly indirections and
systematic "tgid" resolution (which can not be cached by the CPU due to
its THREAD-local nature).
Indeed, we know that a session/stream is tied to a given CPU, thanks to
this we know that the tgid for a given session/stream will never change.
Given that, we are able to store sharded frontend and listener counters
pointer at the session level (namely sess->fe_tgcounters and
sess->li_tgcounters), and once the backend and the server are selected,
we are also able to store backend and server sharded counters
pointer at the stream level (namely s->be_tgcounters and s->sv_tgcounters)
Everywhere we rely on these counters and the stream or session context is
available, we use the fast pointers it instead of the indirect pointers
path to make the pointer resolution a bit faster.
This optimization proved to bring a few percents back, and together with
the previous 75e480d10 commit we now fixed the performance regression (we
are back to back with 3.2 stats performance)
Between 3.2 and 3.3-dev we noticed a noticeable performance regression
due to stats handling. After bisecting, Willy found out that recent
work to split stats computing accross multiple thread groups (stats
sharding) was responsible for that performance regression. We're looking
at roughly 20% performance loss.
More precisely, it is the added indirections, multiplied by the number
of statistics that are updated for each request, which in the end causes
a significant amount of time being spent resolving pointers.
We noticed that the fe_counters_shared and be_counters_shared structures
which are currently allocated in dedicated memory since a0dcab5c
("MAJOR: counters: add shared counters base infrastructure")
are no longer huge since 16eb0fab31 ("MAJOR: counters: dispatch counters
over thread groups") because they now essentially hold flags plus the
per-thread group id pointer mapping, not the counters themselves.
As such we decided to try merging fe_counters_shared and
be_counters_shared in their parent structures. The cost is slight memory
overhead for the parent structure, but it allows to get rid of one
pointer indirection. This patch alone yields visible performance gains
and almost restores 3.2 stats performance.
counters_fe_shared_get() was renamed to counters_fe_shared_prepare() and
now returns either failure or success instead of a pointer because we
don't need to retrieve a shared pointer anymore, the function takes care
of initializing existing pointer.
"log-steps" was already ignored if directly defined in a backend section,
however, when defined in a defaults section it was inherited to all
proxies no matter their capability (ie: including backends).
As configurations often contain more backends than frontends, this would
result in wasted memory given that the log-steps setting is only
considered on frontends.
Let's fix that by preventing the inheritance from defaults section to
anything else than frontends. Also adjust the documentation to mention
that the setting in not relevant for backends.
For listen/frontend/backend, we now want to be able to clean up the
default-server directive that's no longer used past the end of the
section. For this we register a post-section function and perform the
cleanup there.
The default-server entry used to always be allocated. Now we'll postpone
its allocation for the first time we need it, i.e. during a "default-server"
directive, or when inheriting a defaults section which has one. The memory
savings are significant, on a large configuration with 100k backends and
no default-server directive, the memory usage dropped from 800MB RSS to
420MB (380 MB saved). It should be possible to also address configs using
default-server by releasing this entry when leaving the proxy section,
which is not done yet.
Now we only copy the default server's settings if such a default server
exists, otherwise we only initialize it. At the moment it always exists.
The change is mostly performed in srv_settings_cpy() since that's where
each caller passes through, and there's no point duplicating that test
everywhere.
The server struct has gone huge over time (~3.8kB), and having a copy
of it in the defsrv section of the struct proxy costs a lot of RAM,
that is not needed anymore at run time.
This patch replaces this struct with a dynamically allocated one. The
field is allocated and initialized during alloc_new_proxy() and is
freed when the proxy is destroyed for now. But the goal will be to
support freeing it after parsing the section.
findserver() used to check for duplicate server names. These are no
longer accepted in 3.3 so let's get rid of that test and simplify the
code. Note that the function still only uses the list instead of the
tree.
This patch adds the support for the RFC2385 (Protection of BGP Sessions via
the + TCP MD5 Signature Option) for the listeners and the servers. The
feature is only available on Linux. Keywords are not exposed otherwise.
By setting "tcp-md5sig <password>" option on a bind line, TCP segments of
all connections instantiated from the listening socket will be signed with a
16-byte MD5 digest. The same option can be set on a server line to protect
outgoing connections to the corresponding server.
The primary use case for this option is to allow BGP to protect itself
against the introduction of spoofed TCP segments into the connection
stream. But it can be useful for any very long-lived TCP connections.
A reg-test was added and it will be executed only on linux. All other
targets are excluded.
Same motivation as previous commit, proxy last_change is "abused" because
it is used for 2 different purposes, one for stats, and the other one
for process-local internal use.
Let's add a separate proxy-only last_change variable for internal use,
and leave the last_change shared (and thread-grouped) counter for
statistics.
last_change server metric is used for 2 separate purposes. First it is
used to report last server state change date for stats and other related
metrics. But it is also used internally, including in sensitive paths,
such as lb related stuff to take decision or perform computations
(ie: in srv_dynamic_maxconn()).
Due to last_change counter now being split over thread groups since 16eb0fa
("MAJOR: counters: dispatch counters over thread groups"), reading the
aggregated value has a cost, and we cannot afford to consult last_change
value from srv_dynamic_maxconn() anymore. Moreover, since the value is
used to take decision for the current process we don't wan't the variable
to be updated by another process in our back.
To prevent performance regression and sharing issues, let's instead add a
separate srv->last_change value, which is not updated atomically (given how
rare the updates are), and only serves for places where the use of the
aggregated last_change counter/stats (split over thread groups) is too
costly.
Most fe and be counters are good candidates for being shared between
processes. They are now grouped inside "shared" struct sub member under
be_counters and fe_counters.
Now they are properly identified, they would greatly benefit from being
shared over thread groups to reduce the cost of atomic operations when
updating them. For this, we take the current tgid into account so each
thread group only updates its own counters. For this to work, it is
mandatory that the "shared" member from {fe,be}_counters is initialized
AFTER global.nbtgroups is known, because each shared counter causes the stat
to be allocated lobal.nbtgroups times. When updating a counter without
concurrency, the first counter from the array may be updated.
To consult the shared counters (which requires aggregation of per-tgid
individual counters), some helper functions were added to counter.h to
ease code maintenance and avoid computing errors.
proxies, listeners and server shared counters are now managed via helpers
added in one of the previous commits.
When guid is not set (ie: when not yet assigned), shared counters pointer
is allocated using calloc() (local memory) and a flag is set on the shared
counters struct to know how to manipulate (and free it). Else if guid is
set, then it means that the counters may be shared so while for now we
don't actually use a shared memory location the API is ready for that.
The way it works, for proxies and servers (for which guid is not known
during creation), we first call counters_{fe,be}_shared_get with guid not
set, which results in local pointer being retrieved (as if we just
manually called calloc() to retrieve a pointer). Later (during postparsing)
if guid is set we try to upgrade the pointer from local to shared.
Lastly, since the memory location for some objects (proxies and servers
counters) may change from creation to postparsing, let's update
counters->last_change member directly under counters_{fe,be}_shared_get()
so we don't miss it.
No change of behavior is expected, this is only preparation work.
Shareable counters are not tagged as shared counters and are dynamically
allocated in separate memory area as a prerequisite for being stored
in shared memory area. For now, GUID and threads groups are not taken into
account, this is only a first step.
also we ensure all counters are now manipulated using atomic operations,
namely, "last_change" counter is now read from and written to using atomic
ops.
Despite the numerous changes caused by the counters being moved away from
counters struct, no change of behavior should be expected.
We have global proxies_list pointer which is announced as the list of
"all existing proxies", but in fact it only represents regular proxies
declared on the config file through "listen, frontend or backend" keywords
It is ambiguous, and we currently don't have a straightforwrd method to
iterate over all proxies (either public or internal ones) within haproxy
Instead we still have to manually iterate over multiple lists (main
proxies, log-forward proxies, peer proxies..) which is error-prone.
In this patch we add a struct list member (8 bytes) inside struct proxy
in order to store every proxy (except default ones) within a global
"proxies" list which is actually representative for all proxies existing
under haproxy process, like we already have for servers.
proxy_cond_disable() collects and prints cumulated connections for be and
fe proxies no matter their type. With shared stats it may cause issues
because depending on the proxy capabilities only fe or be counters may
be allocated.
In this patch we add some checks to ensure we only try to read from
valid memory locations, else we rely on default values (0).
It is now possile to set a label on a bind line. All sockets attached to
this bind line inherits from this label. The idea is to be able to groud of
sockets. For now, there is no mechanism to create these groups, this must be
done by hand.
In commit b5ee8bebfc ("MINOR: server: always call ssl->destroy_srv when
available"), we made it so srv_drop() doesn't depend on proxy to perform
server cleanup.
It turns out this is now mandatory, because during deinit, free_proxy()
can occur before the final srv_drop(). This is the case when using Lua
scripts for instance.
In 2a9436f96 ("MINOR: lbprm: Add method to deinit server and proxy") we
added a freeing check under srv_drop() that depends on the proxy.
Because of that UAF may occur during deinit when using a Lua script that
manipulate server objects.
To fix the issue, let's perform the lbprm server deinit logic under
free_proxy() directly, where the DEINIT server hooks are evaluated.
Also, to prevent similar bugs in the future, let's explicitly document
in srv_drop() that server cleanups should assume that the proxy may
already be freed.
No backport needed unless 2a9436f96 is.
There are several fields in the appctx structure only used by the CLI. To
make things cleaner, all these fields are now placed in a dedicated context
inside the appctx structure. The final goal is to move it in the service
context and add an API for cli commands to get a command coontext inside the
cli context.
In RFC9110, it is stated that trailers could be merged with the
headers. While it should be performed with a speicial care, it may be a
problem for some applications. To avoid any trouble with such applications,
two new options were added to drop trailers during the message forwarding.
On the backend, "http-drop-request-trailers" option can be enabled to drop
trailers from the requests before sending them to the server. And on the
frontend, "http-drop-response-trailers" option can be enabled to drop
trailers from the responses before sending them to the client. The options
can be defined in defaults sections and disabled with "no" keyword.
This patch should fix the issue #2930.
This changes commit d2a9149f0 ("BUG/MINOR: proxy: always detach a proxy
from the names tree on free()") to be cleaner. Aurlien spotted that
the free(p->id) was indeed already done in proxy_free_common(), which is
called before we delete the node. That's still a bit ugly and it only
works because ebpt_delete() does not dereference the key during the
operation. Better play safe and delete the entry before freeing it,
that's more future-proof.
Stephen Farrell reported in issue #2942 that recent haproxy versions
crash if there's no resolv.conf. A quick bisect with his reproducer
showed that it started with commit 4194f75 ("MEDIUM: tree-wide: avoid
manually initializing proxies") which reorders the proxies initialization
sequence a bit. The crash shows a corrupted tree, typically indicating a
use-after-free. With the help of ASAN it was possible to find that a
resolver proxy had been destroyed and freed before the name insertion
that causes the crash, very likely caused by the absence of the needed
resolv.conf:
#0 0x7ffff72a82f7 in free (/usr/local/lib64/libasan.so.5+0x1062f7)
#1 0x94c1fd in free_proxy src/proxy.c:436
#2 0x9355d1 in resolvers_destroy src/resolvers.c:2604
#3 0x93e899 in resolvers_create_default src/resolvers.c:3892
#4 0xc6ed29 in httpclient_resolve_init src/http_client.c:1170
#5 0xc6fbcf in httpclient_create_proxy src/http_client.c:1310
#6 0x4ae9da in ssl_ocsp_update_precheck src/ssl_ocsp.c:1452
#7 0xa1b03f in step_init_2 src/haproxy.c:2050
But free_proxy() doesn't delete the ebpt_node that carries the name,
which perfectly explains the situation. This patch simply deletes the
name node and Stephen confirmed that it fixed the problem for him as
well. Let's also free it since the key points to p->id which is never
freed either in this function!
No backport is needed since the patch above was first merged into
3.2-dev10.
Same as free_proxy(), but does not free the base proxy pointer (ie: the
proxy itself may not be allocated)
Goal is to be able to cleanup statically allocated dummy proxies.
Split alloc_new_proxy() in two functions: the preparing part is now
handled by setup_new_proxy() which can be called individually, while
alloc_new_proxy() takes care of allocating a new proxy struct and then
calling setup_new_proxy() with the freshly allocated proxy.
For leastconn, servers used to just be stored in an ebtree.
Each server would be one node.
Change that so that nodes contain multiple mt_lists. Each list
will contain servers that share the same key (typically meaning
they have the same number of connections). Using mt_lists means
that as long as tree elements already exist, moving a server from
one tree element to another does no longer require the lbprm write
lock.
We use multiple mt_lists to reduce the contention when moving
a server from one tree element to another. A list in the new
element will be chosen randomly.
We no longer remove a tree element as soon as they no longer
contain any server. Instead, we keep a list of all elements,
and when we need a new element, we look at that list only if it
contains a number of elements already, otherwise we'll allocate
a new one. Keeping nodes in the tree ensures that we very
rarely have to take the lbrpm write lock (as it only happens
when we're moving the server to a position for which no
element is currently in the tree).
The number of mt_lists used is defined as FWLC_NB_LISTS.
The number of tree elements we want to keep is defined as
FWLC_MIN_FREE_ENTRIES, both in defaults.h.
The value used were picked afrer experimentation, and
seems to be the best choice of performances vs memory
usage.
Doing that gives a good boost in performances when a lot of
servers are used.
With a configuration using 500 servers, before that patch,
about 830000 requests per second could be processed, with
that patch, about 1550000 requests per second are
processed, on an 64-cores AMD, using 1200 concurrent connections.
Add two new methods to lbprm, server_deinit() and proxy_deinit(),
in case something should be done at the lbprm level when
removing servers and proxies.
When using hash-based load balancing, requests are always assigned to
the server corresponding to the hash bucket for the balancing key,
without taking maxconn or maxqueue into account, unlike in other load
balancing methods like 'first'. This adds a new backend directive that
can be used to take maxconn and possibly maxqueue in that context. This
can be used when hashing is desired to achieve cache locality, but
sending requests to a different server is preferable to queuing for a
long time or failing requests when the initial server is saturated.
By default, affinity is preserved as was the case previously. When
'hash-preserve-affinity' is set to 'maxqueue', servers are considered
successively in the order of the hash ring until a server that does not
have a full queue is found.
When 'maxconn' is set on a server, queueing cannot be disabled, as
'maxqueue=0' means unlimited. To support picking a different server
when a server is at 'maxconn' irrespective of the queue,
'hash-preserve-affinity' can be set to 'maxconn'.
Migrate recently added log-forward section options, currently stored under
proxy->options2 to proxy->options3 since proxy->options2 is running out of
space and we plan on adding more log-forward options.
proxy->options2 is almost full, yet we will add new log-forward options
in upcoming patches so we anticipate that by adding a new {no_}options3
and cfg_opts3[] to further extend proxy options
This commit introduces the dont-parse-log option to disable log message
parsing, allowing raw log data to be forwarded without modification.
Also, it adds the assume-rfc6587-ntf option to frame log messages
using only non-transparent framing as per RFC 6587. This avoids
missparsing in certain cases (mainly with non RFC compliant messages).
The documentation is updated to include details on the new options and
their intended use cases.
This feature was discussed in GH #2856
This is the introduction of "minsize-req" and "minsize-res".
These two options allow you to set the minimum payload size required for
compression to be applied.
This helps save CPU on both server and client sides when the payload does
not need to be compressed.
For both servers and proxies, use one connection queue per thread-group,
instead of only one. Having only one can lead to severe performance
issues on NUMA machines, it is actually trivial to get the watchdog to
trigger on an AMD machine, having a server with a maxconn of 96, and an
injector that uses 160 concurrent connections.
We now have one queue per thread-group, however when dequeueing, we're
dequeuing MAX_SELF_USE_QUEUE (currently 9) pendconns from our own queue,
before dequeueing one from another thread group, if available, to make
sure everybody is still running.
Add a per-thread group field to struct proxy, that will contain a struct
queue, as well as a new field, "queueslength".
This is currently unused, so should change nothing.
Please note that proxy_init_per_thr() must now be called for each proxy
once the thread groups number is known.
The "421" status can now be specified on retry-on directives. PR_RE_* flags
were updated to remains sorted.
This patch should fix the issue #2794. It is quite simple so it may safely
be backported to 3.1 if necessary.
A QUIC congestion algorithm can be specified on the bind line via
keyword quic-cc-algo. As such, bind_conf structure has a member
quic_cc_algo.
Previously, if quic-cc-algo was set, bind_conf member was initialized to
one of the globally defined CC algo structure. This patch changes
bind_conf quic_cc_algo initialization to point to a dynamically
allocated copy of CC algo structure.
With this change, it will be possible to tweak individually each CC algo
of a bind line. This will be used to activate pacing on top of the
congestion algorithm.
As bind_conf member is dynamically allocated now, its member is now
freed via free_proxy() to prevent any leak.
From time to time we face a configuration with very small timeouts which
look accidental because there could be expectations that they're expressed
in seconds and not milliseconds.
This commit adds a check for non-nul unitless values smaller than 100
and emits a warning suggesting to append an explicit unit if that was
the intent.
Only the common timeouts, the server check intervals and the resolvers
hold and timeout values were covered for now. All the code needs to be
manually reviewed to verify if it supports emitting warnings.
This may break some configs using "zero-warning", but greps in existing
configs indicate that these are extremely rare and solely intentionally
done during tests. At least even if a user leaves that after a test, it
will be more obvious when reading 10ms that something's probably not
correct.
proxy auth_uri struct was manually cleaned up during deinit, but the logic
behind was kind of akward because it was required to find out which ones
were shared or not. Instead, let's switch to a proper refcount mechanism
and free the auth_uri struct directly in proxy_free_common().
add proxy->conf.log_steps eb32 root tree which will be used to store the
log origin identifiers that should result in haproxy emitting a log as
configured by the user using upcoming "log-steps" proxy keyword.
It was chosen to use eb32 tree instead of simple bitfield because despite
the slight overhead it is more future-proof given that we already
implemented the prerequisites for seamless custom log origins registration
that will also be usable from "log-steps" proxy keyword.
The proxy lock state isn't passed down to relax_listener
through dequeue_proxy_listeners, which causes a deadlock
in relax_listener when it tries to get that lock.
Backporting: Older versions didn't have relax_listener and directly called
resume_listener in dequeue_proxy_listeners. lpx should just be passed directly
to resume_listener then.
The bug was introduced in commit 001328873c
[cf: This patch should fix the issue #2726. It must be backported as far as
2.4]
We'll soon delete unreferenced and duplicated named defaults sections
from the list of proxies. The problem with this is that this list (in
fact a name-based tree) is used to release all of them at the end. Let's
add a list of orphaned defaults sections, typically those containing
"http-check send" statements or various other rules, and that are
implicitly inherited by a proxy hence have a non-zero refcount while
also having a name. These now makes it possible to remove them from
the name index while still keeping their memory around for the lifetime
of the process, and cleaning it at the end.
Proxy file names are assigned a bit everywhere (resolvers, peers,
cli, logs, proxy). All these elements were enumerated and now use
copy_file_name(). The only ha_free() call was turned to drop_file_name().
As a bonus side effect, a 300k backend config saved 14 MB of RAM.
With these options, it is possible to accept some invalid messages that may
considered as unsafe and may result as vulnerabilities. The naming is not
explicit enough on this point. These option must really be considered as
dangerous and only used as a temporary workaround. Unfortunately, when used,
it is probably because there are some legacy and unsupported applications in
place. Nevermind. The documentation warns about the use of these
options. Now the name of the options itself is a warning.
So now, "accept-invalid-http-request" and "accept-invalid-http-response"
options are deprecated and replaced by
"accept-unsafe-violations-in-http-request" and
"accept-unsafe-violations-in-http-response" options.
The "429" status can now be specified on retry-on directives. PR_RE_* flags
were updated to remains sorted.
This patch should fix the issue #2687. It is quite simple so it may safely
be backported to 3.0 if necessary.
Some systems require log formats in the CLF format and that meant that I
could not send my logs for proxies in mode tcp to those servers. This
implements a format that uses log variables that are compatble with TCP
mode frontends and replaces traditional HTTP values in the CLF format
to make them stand out. Instead of logging method and URI like this
"GET /example HTTP/1.1" it will log "TCP " and for a response code I
used "000" so it would be easy to separate from legitimate HTTP
traffic. Now your log servers that require a CLF format can see the
timings for TCP traffic as well as HTTP.
Implement a new set of rules labelled as quic-initial.
These rules as specific to QUIC. They are scheduled to be executed early
on Initial packet parsing, prior a new QUIC connection instantiation.
Contrary to tcp-request connection, this allows to reject traffic
earlier, most notably by avoiding unnecessary QUIC SSL handshake
processing.
A new module quic_rules is created. Its main function
quic_init_exec_rules() is called on Initial packet parsing in function
quic_rx_pkt_retrieve_conn().
For the moment, only "accept" and "dgram-drop" are valid actions. Both
are final. The latter drops silently the Initial packet instead of
allocating a new QUIC connection.
