The two algos defining these functions (first and leastconn) do not need the
server's lock. However it's already present in pendconn_process_next_strm()
so the API must be updated so that the functions may take it if needed and
that the callers indicate whether they already own it.
As such, the call places (backend.c and stream.c) now do not take it
anymore, queue.c was unchanged since it's already held, and both "first"
and "leastconn" were updated to take it if not already held.
A quick test on the "first" algo showed a jump from 432 to 565k rps by
just dropping the lock in stream.c!
The remaining contention on the server lock solely comes from
sess_change_server() which takes the lock to add and remove a
stream from the server's actconn list. This is both expensive
and pointless since we have mt-lists, and this list is only
used by the CLI's "shutdown server sessions" command!
Let's migrate to an mt-list and remove the need for this costly
lock. By doing so, the request rate increased by ~1.8%.
The server lock was taken preventively for anything in health_adjust(),
including the static config checks needed to detect that the lock was not
needed, while the function is always called on the response path to update
a server's status. This was responsible for huge contention causing a
performance drop of about 17% on 16 threads. Let's move the lock only
where it should be, i.e. inside the function around the critical sections
only. By doing this, a 16-thread process jumped back from 575 to 675 krps.
This should be backported to 2.3 as the situation degraded there, and
maybe later to 2.2.
There's an issue when a server state changes, we use an integer comparison
to decide whether or not to reschedule a test instead of using a wrapping
timer comparison. This will cause some health-checks not to be immediately
triggered half of the time, and some unneeded calls to task_queue() to be
performed in other cases.
This bug has always been there as it was introduced with the commit that
added the feature, 97f07b832 ("[MEDIUM] Decrease server health based on
http responses / events, version 3"). This may be backported everywhere.
conn_hash_prehash does not need a nul-terminated string, thus it is only
needed to test if the sni sample is not null before using it as
connection hash input.
Moreover, a bug could be introduced between smp_make_safe and
ssl_sock_set_servername call. Indeed, smp_make_safe may call smp_dup
which duplicates the sample in the trash buffer. If another function
manipulates the trash buffer before the call to ssl_sock_set_servername,
the sni sample might be erased. Currently, no function seems to do that
except make_proxy_line in case proxy protocol is used simultaneously
with the sni on the server.
This does not need to be backported.
In session_count_new() the tracked counter was still incremented with
a "++" outside of any lock, resulting in occasional slightly off values
such as the following:
# table: foo, type: string, size:1000, used:1
0xb2a398: key=127.1.2.3 use=0 exp=86398318 sess_cnt=999959 http_req_cnt=1000004
Now with the correct atomic increment:
# table: foo, type: string, size:1000, used:1
0x7f82a4026d38: key=127.1.2.3 use=0 exp=86399294 sess_cnt=1000004 http_req_cnt=1000004
This can be backported to 1.8.
It seems that fd_delete perform the close of the file descriptor
Se we must not close the fd once again after that.
This should fix issues #1128, #1130 and #1131
This patch fix a case which should never happen writing
in output channel since we check available room before
This patch should fix github issue #1132
This patch fix returns code in case of dns_connect_server is called
on unsupported type (which should not happen). Doing this we have
the warranty that after a return 0 the fd is never -1.
This patch should fix github issues #1127, #1128 and #1130
This patch adds a missing test in dns_session_io_handler, getting
the query id from the buffer of the ring. An error should never
happen since messages are completely added atomically.
This bug should fix github issue #1133
move listen status to a helper, defining both status enum and string
definition.
this will be helpful to be reused in prometheus code. It also removes
this hard-to-read nested ternary.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
prometheus approach requires to output all values for a given metric
name; meaning we iterate through all metrics, and then iterate in the
inner loop on all objects for this metric.
In order to allow more code reuse, adapt the stats API to be able to
select one field or fill them all otherwise.
From this patch it should be possible to add support for listen stats in
prometheus.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
The RMAINT admin state is dynamic and should be remove from the
srv_admin_state parameter when a server state is loaded from a server-state
file. Otherwise an erorr is reported, the server-state line is ignored and
the server state is not updated.
This patch should fix the issue #576. It must be backported as far as 1.8.
This patch introduce the new line "server" to set a TCP
nameserver in a "resolvers" section:
server <name> <address> [param*]
Used to configure a DNS TCP or stream server. This supports for all
"server" parameters found in 5.2 paragraph. Some of these parameters
are irrelevant for DNS resolving. Note: currently 4 queries are pipelined
on the same connections. A batch of idle connections are removed every
5 seconds. "maxconn" can be configured to limit the amount of those
concurrent connections and TLS should also usable if the server supports
. The current implementation limits to 4 pipelined
The name of the line in configuration is open to discussion
and could be changed before the next release.
This patch introduce the "dns_stream_nameserver" to use DNS over
TCP on strict nameservers. For the upper layer it is analog to
the api used with udp nameservers except that the user que switch
the name server in "stream" mode at the init using "dns_stream_init".
The fallback from UDP to TCP is not handled and this is not the
purpose of this feature. This is done to choose the transport layer
during the initialization.
Currently there is a hardcoded limit of 4 pipelined transactions
per TCP connections. A batch of idle connections is expired every 5s.
This code is designed to support a maximum DNS message size on TCP: 64k.
Note: this code won't perform retry on unanswered queries this
should be handled by the upper layer
This patch splits current dns.c into two files:
The first dns.c contains code related to DNS message exchange over UDP
and in future other TCP. We try to remove depencies to resolving
to make it usable by other stuff as DNS load balancing.
The new resolvers.c inherit of the code specific to the actual
resolvers.
Note:
It was really difficult to obtain a clean diff dur to the amount
of moved code.
Note2:
Counters and stuff related to stats is not cleany separated because
currently counters for both layers are merged and hard to separate
for now.
This patch splits recv and send functions in two layers. the
lowest is responsible of DNS message transactions over
the network. Doing this we could use DNS message layer
for something else than resolving. Load balancing for instance.
This patch also re-works the way to init a nameserver and
introduce the new struct dns_dgram_server to prepare the arrival
of dns_stream_server and the support of DNS over TCP.
The way to retry a send failure of a request because of EAGAIN
was re-worked. Previously there was no control and all "pending"
queries were re-played each time it reaches a EAGAIN. This
patch introduce a ring to stack messages in case of sent
failure. This patch is emptied if poller shows that the
socket is ready again to push messages.
Counters are currently stored into lowlevel nameservers struct but
most of them are resolving layer data and increased in the upper layer
So this patch renames the prototype used to allocate/dump them with prefix
'resolv' waiting for a clean split.
Some types are specific to resolver code and a renamed using
the 'resolv' prefix instead 'dns'.
-struct dns_query_item {
+struct resolv_query_item {
-struct dns_answer_item {
+struct resolv_answer_item {
-struct dns_response_packet {
+struct resolv_response {
Resolv callbacks are also updated to rely on counters and not on
nameservers.
"show stat domain dns" will now show the parent id (i.e. resolvers
section name).
FreeBSD has a kernel feature (accf) and a sockopt flag similar to the
Linux's TCP_DEFER_ACCEPT to filter incoming data upon ACK. The main
difference is the filter needs to be placed when the socket actually
listens.
Very often, especially since reg-tests, it would be desirable to be able
to conditionally comment out a config block, such as removing an SSL
binding when SSL is disabled, or enabling HTX only for certain versions,
etc.
This patch introduces a very simple nested block management which takes
".if", ".elif", ".else" and ".endif" directives to take or ignore a block.
For now the conditions are limited to empty string or "0" for false versus
a non-nul integer for true, which already suffices to test environment
variables. Still, it needs to be a bit more advanced with defines, versions
etc.
A set of ".notice", ".warning" and ".alert" statements are provided to
emit messages, often in order to provide advice about how to fix certain
conditions.
The "show peers" output has become huge due to the dictionaries making it
less readable. Now this feature has reached a certain level of maturity
which doesn't warrant to dump it all the time, given that it was essentially
needed by developers. Let's make it optional, and disabled by default, only
when "show peers dict" is requested. The default output reminds about the
command. The output has been divided by 5 :
$ socat - /tmp/sock1 <<< "show peers dict" | wc -l
125
$ socat - /tmp/sock1 <<< "show peers" | wc -l
26
It could be useful to backport this to recent stable versions.
This variable is now only used to point on the local server-state file. When
the server-state is global, it is unused. So, we now use "localfilepath"
instead. Thus, the "filepath" variable can safely be removed.
When a local server-state file is loaded, if its name is too long, the error
is not properly handled, resulting to a call to fopen() with the "filepath"
variable set to NULL. To fix the bug, when this error occurs, we jump to the
next proxy, via a "continue" statement. And we take case to set "filepath"
variable after the error handling to be sure.
This patch should fix the issue #1111. It must be backported as far as 1.6.
When a connect rule is evaluated a test is performed on the "port" variable
while it is set to 0 just on the line just above. Just remove this useless
test to make ccpcheck happy.
This patch fixes the issue #1113.
Now it becomes possible to specify "from foo" on a frontend/listen/backend
or even on a "defaults" line, to mention that defaults section "foo" needs
to be used to preset the proxy's settings.
When not set, the last section remains used. In case the designated name
is found at multiple places, it is rejected and an error indicates two
occurrences of the same name. Similarly, if the section name is found,
its name must only use valid characters. This allows multiple named
defaults section to continue to coexist without the risk that they will
cause trouble by accident.
When it comes to "defaults" relying on another defaults, what happens is
just that a new defaults section is created from the designated one. This
will make it possible for example to reuse some settings such as log-format
like below:
defaults tcp-clear
log stdout local0 info
log-format "%ci:%cp/%b/%si:%sp %ST %ts %U/%B %{+Q}r"
defaults tcp-ssl
log stdout local0 info
log-format "%ci:%cp/%b/%si:%sp %ST %ts %U/%B %{+Q}r ssl=%sslv"
defaults http-clear from tcp-clear
mode http
defaults http-ssl from tcp-ssl
mode http
frontend fe1 from http-clear
bind :8001
frontend fe2 from http-ssl
bind :8002
A small corner case remains in the error detection, if a second defaults
section appears with the same name after the point where it was used, and
nobody references it, the duplicate will not be detected. This could be
addressed by performing the syntactic checks in check_config_validity(),
and by postponing the freeing of the defaults, after tagging a defaults
section as explicitly looked up by another section. This doesn't seem
that important at the moment though.
Now default proxies are stored into a dedicated tree, sorted by name.
Only unnamed entries are not kept upon new section creation. The very
first call to cfg_parse_listen() will automatically allocate a dummy
defaults section which corresponds to the previous static one, since
the code requires to have one at a few places.
The first immediately visible benefit is that it allows to reuse
alloc_new_proxy() to allocate a defaults section instead of doing it by
hand. And the secret goal is to allow to keep multiple named defaults
section in memory to reuse them from various proxies.
Now we'll have a tree of named defaults sections. The regular insertion
and lookup functions take care of the capability in order to select the
appropriate tree. A new function proxy_destroy_defaults() removes a
proxy from this tree and frees it entirely.
In order to make the default proxy configurable, we'll need to have a
pointer to it which might differ from &defproxy. cfg_parse_listen()
now gets curr_defproxy for this.
We don't want to expose this one anymore as we'll soon keep multiple
default proxies. Let's move it inside the parser which is the only
place which still uses it, and initialize it on the fly once needed
instead of doing it at boot time.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
The default proxy was passed as a variable, which in addition to being
a PITA to deal with in the config parser, doesn't feel safe to use when
it ought to be const.
This will only affect new code so no backport is needed.
In proxy_free_defaults(); none of the free() calls was followed by a
pointer reset. Not only it's hard to figure if one of them is duplicated,
but this code started to call other functions which might or might not
rely on such just freed pointers. Let's reset them as they should be to
make sure there will never be any case of use-after-free. The 3 functions
called there were inspected and are all unaffected by this so this remains
safe to do right now.
This used to be open-coded in cfgparse-listen.c when facing a "defaults"
keyword. Let's move this into proxy_free_defaults(). This code is ugly and
doesn't even reset the just freed pointers. Let's not change this yet.
This code should probably be merged with a generic proxy deinit function
called from deinit(). However there's a catch on uri_auth which cannot be
freed because it might be used by one or several proxies. We definitely
need refcounts there!
The proxy initialization code relies on three phases, allocation,
pre-initialization, and assignments from defaults. This last part is
entirely taken from the defaults proxy when arguments are set. This
sensibly complexifies the initialization code as it requires to always
have a default proxy.
This patch instead first applies the original default settings on a
proxy, and then uses those from a default proxy only if one such is
used. This will allow to initialize a proxy out of any default proxy
while still using valid defaults. A careful inspection of the function
showed that only 4 fields used to be set regardless of the default
proxy, and those were moved to init_new_proxy() where they ought to
have been in the first place.
This new function takes over the old open-coding that used to be done
for too long in cfg_parse_listen() and it now does everything at once
in a proxy-centric function. The function does all the job of allocating
the structure, initializing it, presetting its defaults from the default
proxy and checking for errors. The code was almost unchanged except for
defproxy being passed as a pointer, and the error message being passed
using memprintf().
This change will be needed to ease reuse of multiple default proxies,
or to create dynamic backends in a distant future.
init_default_instance() was still left in cfgparse.c which is not the
best place to pre-initialize a proxy. Let's place it in proxy.c just
after init_new_proxy(), take this opportunity for renaming it to
proxy_preset_defaults() and taking out init_new_proxy() from it, and
let's pass it the pointer to the default proxy to be initialized instead
of implicitly assuming defproxy. We'll soon be able to exploit this.
Only two call places had to be updated.
This is just an API bug but it's annoying when trying to tidy the code.
The source list passed in argument must be a const and not a variable,
as it's typically the list head from a default proxy and must obviously
not be modified by the function. No backport is needed as it only impacts
new code.
This is just an API bug but it's annoying when trying to tidy the code.
The default proxy passed in argument must be a const and not a variable.
No backport is needed as it only impacts new code.
The very old error message indicating that a proxy name is mandatory
still had a reference to the optional addr:port argument while this one
is explicitly rejected a few lines later since at least 1.9.
This is harmless but confusing. This can be backported to 2.0.
In 2.1, commit ee4f5f83d ("MINOR: stats: get rid of the ST_CONVDONE flag")
introduced a subtle bug. By testing curproxy against defproxy in
check_config_validity(), it tried to eliminate the need for a flag
to indicate that stats authentication rules were already compiled,
but by doing so it left the issue opened for the case where a new
defaults section appears after the two proxies sharing the first
one:
defaults
mode http
stats auth foo:bar
listen l1
bind :8080
listen l2
bind :8181
defaults
# just to break above
This config results in:
[ALERT] 042/113725 (3121) : proxy 'f2': stats 'auth'/'realm' and 'http-request' can't be used at the same time.
[ALERT] 042/113725 (3121) : Fatal errors found in configuration.
Removing the last defaults remains OK. It turns out that the cleanups
that followed that patch render it useless, so the best fix is to revert
the change (with the up-to-date flags instead). The flag was marked as
belonging to the config. It's not exact but it's the closest to the
reality, as it's not there to configure the behavior but ti mention
that the config parser did its job.
This could be backported as far as 2.1, but in practice it looks like
nobody ever hit it.
Since commit 1.3.14 with commit 1fa3126ec ("[MEDIUM] introduce separation
between contimeout, and tarpit + queue"), check_config_validity() looks
at the last defaults section to update all proxies' queue and tarpit
timeouts if they were not set!
This was apparently an attempt to properly set them on the fallback values,
except that the fallback values were taken from the default proxy before
looking at the current proxy itself. The worst part of it is that it might
have randomly worked by accident for some configurations when there was a
single defaults section, but has certainly caused too short queue
expirations once another defaults section was added later in the file with
these explicitly defined.
Let's remove the defproxy part and keep only the curproxy ones. This could
be backported everywhere, the bug has been there for 13 years.
Since the beginning, this directive is documented to accept an optional file
name. But it should also be possible to use it without any argument to use
the backend name as file name. However, when no argument is provided, an
error is reported during the configuration parsing requesting an argument, a
file name or "use-backend-name". And This last special argument is not
documented.
So, to respect the documentation and to avoid configuration breakages, all
modes are now supported. If this directive is called with no argument or
with "use-backend-name", the backend name is use as file name for the
server-state file. Otherwise, the provided string is used.
In addition, we take care to release any previously allocated file name in
case this directive is defines multiple times in the same backend. And an
error is reported if more than one argument are defined. Finally, the
documentation is updated accordingly. Sections supporting this directive are
also mentioned.
This patch should be backported as far as 1.6.
server health checks and agent parameters are written the same way as
others to be able to enahcne code reuse: basically we make use of
parsing and assignment at the same place. It makes it difficult for
error handling to know whether srv object was modified partially or not.
The problem was already present with SRV resolution though.
I was a bit puzzled about the approach to take to be honest, and I did
not wanted to go into a full refactor, so I assumed it was ok to simply
notify whether the line was failed or partially applied.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
logical followup from cli commands addition, so that the state server
file stays compatible with the changes made at runtime; use previously
added helper to load server attributes.
also alloc a specific chunk to avoid mixing with other called functions
using it
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Even if it is possibly too much work for the current usage, it makes
sure we don't break states file from v2.3 to v2.4; indeed, since v2.3,
we introduced two new fields, so we put them aside to guarantee we can
easily reload from a version 1.
The diff seems huge but there is no specific change apart from:
- introduce v2 where it is needed (parsing, update)
- move away from switch/case in update to be able to reuse code
- move srv lock to the whole function to make it easier
this patch confirm how painful it is to maintain this functionality.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
this patch allows to set agent port at runtime. In order to align with
both `addr` and `check-addr` commands, also add the possibility to
optionnaly set port on `agent-addr` command. This led to a small
refactor in order to use the same function for both `agent-addr` and
`agent-port` commands.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
this patch allows to set server health check address at runtime. In
order to align with `addr` command, also allow to set port optionnaly.
This led to a small refactor in order to use the same function for both
`check-addr` and `check-port` commands.
for `check-port`, we however don't permit the change anymore if checks
are not enabled on the server.
This command becomes more and more useful for people having a consul
like architecture:
- the backend server is located on a container with its own IP
- the health checks are done the consul instance located on the host
with the host IP
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Use the proxy protocol frame if proxy protocol is activated on the
server line. Do not add anymore these connections in the private list.
If some requests are made with the same proxy fields, they can reuse
the idle connection.
The reg-tests proxy_protocol_send_unique_id must be adapted has it
relied on the side effect behavior that every requests from a same
connection reused a private server connection. Now, a new connection is
created as expected if the proxy protocol fields differ.
The source address is used as an input to the the server connection hash. The
address and port are used as separate hash inputs. Do not add anymore these
connections in the private list.
This parameter is set only if used in the transparent-proxy mode.
The destination address is used as an input to the server connection hash. The
address and port are used as separated hash inputs. Note that they are not used
when statically specified on the server line. This is only useful for dynamic
destination address.
This is typically used when the server address is dynamically set via the
set-dst action. The address and port are separated hash parameters.
Most notably, it should fixed set-dst use case (cf github issue #947).
Change the API of the function used to allocate the stream target
address. This is done in order to be able to allocate the destination
address and use it to reuse a connection sharing with the same address.
In particular, the flag stream SF_ADDR_SET is now set outside of the
function.
The sni parameter is an input to the server connection hash. Do not add
anymore connections with dynamic sni in the private list. Thus, it is
now possible to reuse a server connection if they use the same sni.
Compare the connection hash when reusing a connection from the session.
This ensures that a private connection is reused only if it shares the
same set of parameters.
The pointer of the target server is used as a first parameter for the
server connection hash calcul. This prevents the hash to be null when no
specific parameters are present, and can serve as a simple defense
against an attacker trying to reuse a non-conform connection.
This is a preliminary work for the calcul of the backend connection
hash. A structure conn_hash_params is the input for the operation,
containing the various specific parameters of a connection.
The high bits of the hash will reflect the parameters present as input.
A set of macros is written to manipulate the connection hash and extract
the parameters/payload.
With http-reuse always, if no matching safe connection is found, check
in idle tree for a matching one. This is needed because now idle
connections can be differentiated from each other.
If only the safe tree was checked because not empty, but did not contain
a matching connection, we could miss matching entry in idle tree.
If no matching connection is found on available, check on idle/safe
trees for a matching one. This is needed because now idle connections
can be differentiated from each other.
If only the available list was checked because not empty, but did not
contain a matching connection, we could miss matching entries in idle or
safe trees.
The server idle/safe/available connection lists are replaced with ebmb-
trees. This is used to store backend connections, with the new field
connection hash as the key. The hash is a 8-bytes size field, used to
reflect specific connection parameters.
This is a preliminary work to be able to reuse connection with SNI,
explicit src/dst address or PROXY protocol.
This is a preparation work for connection reuse with sni/proxy
protocol/specific src-dst addresses.
Protect every access to idle conn lists with a lock. This is currently
strictly not needed because the access to the list are made with atomic
operations. However, to be able to reuse connection with specific
parameters, the list storage will be converted to eb-trees. As this
structure does not have atomic operation, it is mandatory to protect it
with a lock.
For this, the takeover lock is reused. Its role was to protect during
connection takeover. As it is now extended to general idle conns usage,
it is renamed to idle_conns_lock. A new lock section is also
instantiated named IDLE_CONNS_LOCK to isolate its impact on performance.
The wrong lock seems to be held when trying to remove another thread
connection if max fd limit has been reached (locking the current thread
instead of the target thread lock).
This could be backported up to 2.0.
This patch removes unecessary tests on p or pp pointers in
pendconn_process_next_strm() function. This should make cppcheck happy and
avoid false report of null pointer dereference.
This patch should fix the issue #1036.
this is pure cleanup, no need to backport
2116 if ((end - 1) == (payload + strlen(PAYLOAD_PATTERN))) {
2117 /* if the payload pattern is at the end */
2118 s->pcli_flags |= PCLI_F_PAYLOAD;
CID 1399833 (#1 of 1): Unused value (UNUSED_VALUE)assigned_value: Assigning value from reql to ret here, but that stored value is overwritten before it can be used.
2119 ret = reql;
2120 }
This patch fixes the issue #1048.
When an invalid character is found during parsing in parse_dotted_uints()
function, the allocated array of uint must be released. This patch fixes a
memory leak on error path during the configuration parsing.
This patch should fix the issue #1106. It should be backported as far as
2.0. Note that, for 2.1 and 2.0, the function is in src/standard.c
In H1, H2 and FCGI muxes, b_realign_if_empty() is called to reset the head
of an empty buffer before setting it a specific value to permit the
zero-copy. Thus, we can remove call to b_realign_if_empty().
When a message is sent, an extra check is performed when the parser is
switch to MSG_DONE state to be sure the EOM flag is really set. This flag is
quite new and replaces the EOM block. Thus, this test is a safeguard waiting
for a proper refactoring of the outgoing side.
In the H2 mux, when a empty DATA frame is used to finish a message, just to
set the ES flag, we now only set the EOM flag on the HTX message. However,
if the HTX message is empty, this event will not be properly handled on the
other side because there is no effective data to handle. Thus, it is
interpreted as an abort by the H1 mux.
It is in part caused by the current H1 mux design but also because there is
no way to emit empty HTX block (NOOP HTX block) or to wakeup a mux for send
when there is no data to finish some internal processing.
Thus, for now, to work around this limitation, an EOT HTX block is added by
the H2 mux if a EOM flag is added on an empty HTX message. This case is only
possible when an empty DATA frame with the ES flag is received.
This fix is specific for 2.4. No backport needed.
In HTTP/2, we may have trailers for messages with a Content-length
header. Thus, when the H2 mux receives a HEADERS frame at the end of a
message, it always emits TLR and EOT HTX blocks. On the H1 mux, if this
happens, these blocks are just skipped because we cannot emit trailers for a
non-chunked message. But the EOT HTX block must not be blindly
ignored. Indeed, there is no longer EOM HTX block to mark the end of the
message. Thus the EOT block, when found, is the end of the message. So we
must handle it to swith in MSG_DONE state.
This fix is specific for 2.4. No backport needed.
When payload is received for a bodyless response, for instance a response to
a HEAD request, it is silently skipped. Unfortunately, when this happens,
the end of the message is not properly handled. The response remains in the
MSG_DATA state (or MSG_TRAILERS if the message is chunked). In addition,
when a zero-copy is possible, the data are not removed from the channel
buffer and the H1 connection is killed because an error is then triggered.
To fix the bug, the zero-copy is disabled for bodyless responses. It is not
a problem because there is no copy at all. And the last block (DATA or EOT)
is now properly handled.
This bug was introduced by the commit e5596bf53 ("MEDIUM: mux-h1: Don't emit
any payload for bodyless responses").
This fix is specific for 2.4. No backport needed.
During the message parsing, if in MSG_DONE state, the CS_FL_EOI flag must
always be set on the conn-stream if following conditions are met :
* It is a response or
* It is a request but not a protocol upgrade nor a CONNECT.
For now, there is no test on the message type (request or response). Thus
the CS_FL_EOI flag is not set for a response with a "Connection: upgrade"
header but not a 101 response.
This bug was introduced by the commit 3e1748bbf ("BUG/MINOR: mux-h1: Don't
set CS_FL_EOI too early for protocol upgrade requests"). It was backported
as far as 2.0. Thus, this patch must also be backported as far as 2.0.
If internal error is reported by the mux during HTTP request parsing, the
HTTP error counter should not be incremented. It should only be incremented
on parsing error to reflect errors caused by clients.
This patch must be backported as far as 2.0. During the backport, the same
must be performed for 408-request-time-out errors.
The HTTP error counter reflects the number of errors caused by
clients. Thus, In the H1 mux, it should only be increment on parsing errors.
This fix is specific for 2.4. No backport needed.
Historically we've been counting lots of client-triggered events in stick
tables to help detect misbehaving ones, but we've been missing the same on
the server side, and there's been repeated requests for being able to count
the server errors per URL in order to precisely monitor the quality of
service or even to avoid routing requests to certain dead services, which
is also called "circuit breaking" nowadays.
This commit introduces http_fail_cnt and http_fail_rate, which work like
http_err_cnt and http_err_rate in that they respectively count events and
their frequency, but they only consider server-side issues such as network
errors, unparsable and truncated responses, and 5xx status codes other
than 501 and 505 (since these ones are usually triggered by the client).
Note that retryable errors are purposely not accounted for, so that only
what the client really sees is considered.
With this it becomes very simple to put some protective measures in place
to perform a redirect or return an excuse page when the error rate goes
beyond a certain threshold for a given URL, and give more chances to the
server to recover from this condition. Typically it could look like this
to bypass a URL causing more than 10 requests per second:
stick-table type string len 80 size 4k expire 1m store http_fail_rate(1m)
http-request track-sc0 base # track host+path, ignore query string
http-request return status 503 content-type text/html \
lf-file excuse.html if { sc0_http_fail_rate gt 10 }
A more advanced mechanism using gpt0 could even implement high/low rates
to disable/enable the service.
Reg-test converteers_ref_cnt_never_dec.vtc was updated to test it.
The sleep time calculation in next_event_delay() was wrong because it
was dividing 999 by the number of pending events, and was directly
responsible for an observation made a long time ago that listeners
would eat all the CPU when hammered while globally rate-limited,
because the more the queued events, the least it would wait, and would
ignore the configured frequency to compute the delay.
This was addressed in various ways in listeners through the switch to
the FULL state and the wakeup of manage_global_listener_queue() that
avoids this fast loop, but the calculation made there remained wrong
nevertheless. It's even visible with this patch that the accept
frequency is much more accurate at low values now; for example,
configuring a maxconrate of 10 would give between 8.99 and 11.0 cps
before this patch and between 9.99 and 10.0 with it.
Better fix it now in case it's reused anywhere else and causes confusion
again. It maybe be backported but is probably not worth it.
When adding the server side support for certificate update over the CLI
we encountered a design problem with the SSL session cache which was not
locked.
Indeed, once a certificate is updated we need to flush the cache, but we
also need to ensure that the cache is not used during the update.
To prevent the use of the cache during an update, this patch introduce a
rwlock for the SSL server session cache.
In the SSL session part this patch only lock in read, even if it writes.
The reason behind this, is that in the session part, there is one cache
storage per thread so it is not a problem to write in the cache from
several threads. The problem is only when trying to write in the cache
from the CLI (which could be on any thread) when a session is trying to
access the cache. So there is a write lock in the CLI part to prevent
simultaneous access by a session and the CLI.
This patch also remove the thread_isolate attempt which is eating too
much CPU time and was not protecting from the use of a free ptr in the
session.
both SSL_CTX_set_msg_callback and SSL_CTRL_SET_MSG_CALLBACK defined since
ea262260469e49149cb10b25a87dfd6ad3fbb4ba, we can safely switch to that guard
instead of OpenSSL version
Because of a buggy tests when processing the EOH HTX block, an extra CRLF is
added for empty chunked messages. This bug was introduced by the commit
d1ac2b90c ("MAJOR: htx: Remove the EOM block type and use HTX_FL_EOM
instead").
This fix is specific for 2.4. No backport needed.
special guard macros HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT was defined earlier
exactly for guarding SSL_CTX_add_server_custom_ext, let us use it wherever
appropriate
HAVE_SSL_CTX_ADD_SERVER_CUSTOM_EXT was introduced in ec60909871
however it was defined as HAVE_SL_CTX_ADD_SERVER_CUSTOM_EXT (missing "S")
let us fix typo
The demux loop could quit on missing data but the H2_CF_END_REACHED flag
would not be set in this case. This fixes a remaining situation where
previous commit f09612289 ("BUG/MEDIUM: mux-h2: handle remaining read0
cases") could not be sufficient and still leave CLOSE_WAIT. It's harder
to reproduce but was still observed in prod.
Now we quit via the end of the loop which already takes care of shutr.
This should be backported along with the patch above as far as 2.0.
If allocating a connection object failed right after a successful accept
on a listener, the new file descriptor was not properly closed.
This fixes GitHub issue #905.
It can be backported to 2.3.
During error files conversion to HTX message, in http_str_to_htx(), if a
file is empty, the corresponding buffer's area is initialized with a
malloc(0) and its size is set to 0. There is no problem here. The behaviour
is totally defined. But it is not really intuitive. Instead, we can simply
set the area to NULL.
This patch should fix the issue #1022.
Commit 3d4631fec ("BUG/MEDIUM: mux-h2: fix read0 handling on partial
frames") tried to address an issue introduced in commit aade4edc1 where
read0 wasn't properly handled in the middle of a frame. But the fix was
incomplete for two reasons:
- first, it would set H2_CF_RCVD_SHUT in h2_recv() after detecting
a read0 but the condition was guarded by h2_recv_allowed() which
explicitly excludes read0 ;
- second, h2_process would only call h2_process_demux() when there
were still data in the buffer, but closing after a short pause to
leave a buffer empty wouldn't be caught in this case.
This patch fixes this by properly taking care of the received shutdown
and by also waking up h2_process_demux() on an empty buffer if the demux
is not blocked.
Given the patches above were tagged for backporting to 2.0, this one
should be as well.
FD dumps are not always easy to match against netstat dumps, and often
require an lsof as a third dump. Let's emit the socket family, and the
local and remore ports when the FD is an IPv4/IPv6 socket, this will
significantly ease the matching.
The CO_FL_EARLY_SSL_HS flag was inconditionally set on the connection,
resulting in SSL_read_early_data() always being used first in handshake
calculations. While this seems to work well (probably that there are
fallback paths inside openssl), it's particularly confusing and makes
the debugging quite complicated. It possibly is not optimal by the way.
This flag ought to be set only when early_data is configured on the bind
line. Apparently there used to be a good reason for doing it this way in
1.8 times, but it really does not make sense anymore. It may be OK to
backport this to 2.3 if this helps with troubleshooting, but better not
go too far as it's unlikely to fix any real issue while it could introduce
some in old versions.
in the same manner of agentaddr, we now:
- permit to set agentport through `port` keyword, like it is the case
for agentaddr through `addr`
- set the priority on `agent-port` keyword when used
- add a flag to be able to test when the value is set like for agentaddr
it makes the behaviour between `addr` and `port` more consistent.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
small consistency problem with `addr` and `agent-addr` options:
for the both options, the last one parsed is always used to set the
agent-check addr. Thus these two lines don't have the same behavior:
server ... addr <addr1> agent-addr <addr2>
server ... agent-addr <addr2> addr <addr1>
After this patch `agent-addr` will always be the priority option over
`addr`. It means we test the flag before setting agentaddr.
We also fix all the places where we did not set the flag to be coherent
everywhere.
I was not really able to determine where this issue is coming from. So
it is probable we may backport it to all stable version where the agent
is supported.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
We can currently change the check-port using the cli command `set server
check-port` but there is a consistency issue when using server state.
This patch aims to fix this problem but will be also a good preparation
work to get rid of checkport flag, so we are able to know when checkport
was set by config.
I am fully aware this is not making github #953 moving forward, I
however think this might be acceptable while waiting for a proper
solution and resolve consistency problem faced with port settings.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
While trying to fix some consistency problem with the config file/cli
(e.g. check-port cli command does not set the flag), we realised
checkport flag was not necessarily needed. Indeed tcpcheck uses service
port as the last choice if check.port is zero. So we can assume if
check.port is zero, it means it was never set by the user, regardless if
it is by the cli or config file. In the longterm this will avoid to
introduce a new consistency issue if we forget to set the flag.
in the same manner of checkport flag, we don't really need checkaddr
flag. We can assume if checkaddr is not set, it means it was never set
by the user or config.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
When a server dns resolution is performed, there is no reason to set an
unconfigured check port with the server port. Because by default, if the
check port is not set, the server's one is used. Thus we can remove this
useless assignment. It is mandatory for next improvements.
When the server state is loaded from a server-state file, there is no reason
to set an unconfigured check port with the server port. Because by default,
if the check port is not set, the server's one is used. Thus we can remove
this useless assignment. It is mandatory for next improvements.
while reading `update_server_addr_port` I found out some things which
can be seen as incoherency. I hope I did not overlooked anything:
- one comment is stating check's address should be updated if it uses
the server one; however the condition checks if `SRV_F_CHECKADDR` is
set; this flag is set when a check address is set; result is that we
override the check address where I was not expecting it. In fact we
don't need to update anything here as server addr is used when check
addr is not set.
- same goes for check agent addr
- for port, it is a bit different, we update the check port if it is
unset. This is harmless because we also use server port if check port
is unset. However it creates some incoherency before/after using this
command, as check port should stay unset througout the life of the
process unless it is is set by `set server check-port` command.
quite hard to locate the origin of this this issue but the function was
introduced in commit d458adcc52 ("MINOR:
new update_server_addr_port() function to change both server's ADDR and
service PORT"). I was however not able to determine whether this is due
to a change of behavior along the years. So this patch can potentially
be backported up to v1.8 but we must be careful while doing so, as the
code has changed a lot. That being said, the bug being not very
impacting I would be fine keeping it for 2.4 only.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Flush the SSL session cache when updating a certificate which is used on a
server line. This prevent connections to be established with a cached
session which was using the previous SSL_CTX.
This patch also replace the ha_barrier with a thread_isolate() since there
are more operations to do. The reg-test was also updated to remove the
'no-ssl-reuse' keyword which is now uneeded.
Duplicate titles for the stats H2_ST_{OPEN,TOTAL}_{CONN,STREAM}. These
entries are used on csv for the heading.
This must be backported up to 2.3.
This fixes the github issue #1102.
As spotted in issue #822, we're having a problem with error detection in
the SSL layer. The problem is that on an overwhelmed machine, accepted
connections can start to pile up, each of them requiring a slow handshake,
and during all this time if the client aborts, the handshake will still be
calculated.
The error controls are properly placed, it's just that the SSL layer
reads records exactly of the advertised size, without having the ability
to encounter a pending connection error. As such if injecting many TLS
connections to a listener with a huge backlog, it's fairly possible to
meet this situation:
12:50:48.236056 accept4(8, {sa_family=AF_INET, sin_port=htons(62794), sin_addr=inet_addr("127.0.0.1")}, [128->16], SOCK_NONBLOCK) = 1109
12:50:48.236071 setsockopt(1109, SOL_TCP, TCP_NODELAY, [1], 4) = 0
(process other connections' handshakes)
12:50:48.257270 getsockopt(1109, SOL_SOCKET, SO_ERROR, [ECONNRESET], [4]) = 0
(proof that error was detectable there but this code was added for the PoC)
12:50:48.257297 recvfrom(1109, "\26\3\1\2\0", 5, 0, NULL, NULL) = 5
12:50:48.257310 recvfrom(1109, "\1\0\1\3"..., 512, 0, NULL, NULL) = 512
(handshake calculation taking 700us)
12:50:48.258004 sendto(1109, "\26\3\3\0z"..., 1421, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = -1 EPIPE (Broken pipe)
12:50:48.258036 close(1109) = 0
The situation was amplified by the multi-queue accept code, as it resulted
in many incoming connections to be accepted long before they could be
handled. Prior to this they would have been accepted and the handshake
immediately started, which would have resulted in most of the connections
waiting in the the system's accept queue, and dying there when the client
aborted, thus the error would have been detected before even trying to
pass them to the handshake code.
As a result, with a listener running on a very large backlog, it's possible
to quickly accept tens of thousands of connections and waste time slowly
running their handshakes while they get replaced by other ones.
This patch adds an SO_ERROR check on the connection's FD before starting
the handshake. This is not pretty as it requires to access the FD, but it
does the job.
Some improvements should be made over the long term so that the transport
layers can report extra information with their ->rcv_buf() call, or at the
very least, implement a ->get_conn_status() function to report various
flags such as shutr, shutw, error at various stages, allowing an upper
layer to inquire for the relevance of engaging into a long operation if
it's known the connection is not usable anymore. An even simpler step
could probably consist in implementing this in the control layer.
This patch is simple enough to be backported as far as 2.0.
Many thanks to @ngaugler for his numerous tests with detailed feedback.
The "abort ssl cert" command is buggy and removes the current ckch store,
and instances, leading to SNI removal. It must only removes the new one.
This patch also adds a check in set_ssl_cert.vtc and
set_ssl_server_cert.vtc.
Must be backported as far as 2.2.
In order to unify prometheus and stats description, we need to remove
some field reference which are specific to stats implementation:
- `scur` in max current sessions (also reword current session)
- `rate` in max sessions
- `req_rate` in max requests
- `conn_rate` in max connections
Signed-off-by: William Dauchy <wdauchy@gmail.com>
In order to unify prometheus and stats description, we need to clarify
the description for pending connections.
- remove the BE reference in counters struct, as it is also used in
servers
- remove reference of `qcur` field in description as it is specific to
stats implemention
- try to reword cur and max pending connections description
Signed-off-by: William Dauchy <wdauchy@gmail.com>
The function get_check_status_result() can now be used to get the result
code (CHK_RES_*) corresponding to a check status (HCHK_STATUS_*). It will be
used by the Prometheus exporter when reporting the check status of a server.
During the call to thread_isolate(), some other threads might have
performed some task_wakeup() which will have a call date past the
one we retrieved. It could be avoided by taking the current date
once we're alone but this would significantly affect the latency
measurements by adding the isolation time. Instead we're now only
accounting positive times, so that late wakeups normally appear
with a zero latency.
No backport is needed, this is 2.4.
In h2s_bck_make_req_headers() function, in the loop on the HTX blocks, the
most common blocks, the headers, are now handled in first, before the
start-line. The same change was already performed on the response HEADERS
frames. Thus the code is more consistent now.
When a HEADERS frame is sent, it is always when an HTX start-line block is
found. Thus, in h2s_bck_make_req_headers() and h2s_frt_make_resp_headers()
functions, it is useless to tests the start-line. Instead of being too
defensive, we use BUG_ON() now because it must not happen and must be
handled as a bug.
This patch should fix the issue #1086.
The list is always defined by definition. Thus there is no reason to test
it. There is also plenty of checks on arguments types while it is already
validated during the configuration parsing. But one thing at a time.
This patch should fix the issue #1087.
The sample fetch functions must always be called with a valid argument
list. When called by hand, if there is no argument to pass, empty_arg_list must
be used.
In the stick-table code, there are some calls to smp_fetch_src() with NULL as
argument list. It is changed to use empty_arg_list instead. It is not really a
bug because smp_fetch_src() does not use the argument list. But it is an API
bug.
This patch may be backported to all stable branches as a cleanup.
h1_process_output() function is never called with no data to send (count ==
0). Thus, the first test on count, at the beginning of the function is
useless and may be removed. This way, by reading the code, it is obvious the
<chn_htx> variable is always defined.
This patch should fix the issue #1085.
This handler can take quite some time as it deletes a large number of
entries under a lock, let's export it so that it's immediately visible
in "show profiling".
The check I/O handler, process_chk_conn and server_warmup are often
present in complex backtraces as they're impacted by locking or I/O
issues. Let's export them so that they resolve cleanly.
This finally adds the long-awaited solution to inspect the run queues
and figure what is eating the CPU or causing latencies. We can even see
the experienced latencies when profiling is enabled. Example on a
saturated process:
> show tasks
Running tasks: 14983 (4 threads)
function places % lat_tot lat_avg
process_stream 4948 33.0 5.840m 70.82ms
h1_io_cb 2535 16.9 - -
main+0x9e670 2508 16.7 2.930m 70.10ms
ssl_sock_io_cb 2499 16.6 - -
si_cs_io_cb 2493 16.6 - -
If a user enables profiling by hand, it makes sense to reset the stats
counters to provide fresh new measurements. Therefore it's worth using
this as the standard method to reset counters.
"show profiling" will now dump the stats collected by the scheduler if
profiling was previously enabled. This will immediately make it obvious
what functions are responsible for others' high latencies or which ones
are suffering from others, and should help spot issues like undesired
wakeups.
Example:
Per-task CPU profiling : on # set profiling tasks {on|auto|off}
Tasks activity:
function calls cpu_tot cpu_avg lat_tot lat_avg
si_cs_io_cb 5569479 23.37s 4.196us - -
h1_io_cb 5558654 13.60s 2.446us - -
process_stream 250841 1.476s 5.882us 3.499s 13.95us
main+0x9e670 198 - - 5.526ms 27.91us
task_run_applet 17 1.509ms 88.77us 205.8us 12.11us
srv_cleanup_idle_connections 12 44.51us 3.708us 25.71us 2.142us
main+0x158c80 9 48.72us 5.413us - -
srv_cleanup_toremove_connections 5 165.1us 33.02us 123.6us 24.72us
Now when the profiling is enabled, the scheduler wlil update per-function
task-level statistics on number of calls, cpu usage and lateny, that could
later be checked using "show profiling". This will immediately make it
obvious what functions are responsible for others' high latencies or which
ones are suffering from others, and should help spot issues like undesired
wakeups. For now the stats are only collected but not reported (though they
are readable from sched_activity[] under gdb).
The new sched_activity structure will be used to collect task-level
activity based on the target function. The principle is to declare a
large enough array to make collisions rare (256 entries), and hash
the function pointer using a reduced XXH to decide where to store the
stats. On first computation an entry is definitely assigned to the
array and it's done atomically. A special entry (0) is used to store
collisions ("others"). The goal is to make it easy and inexpensive for
the scheduler code to use these to store #calls, cpu_time and lat_time
for each task.
In 2.0, commit d2d3348ac ("MINOR: activity: enable automatic profiling
turn on/off") introduced an automatic mode to enable/disable profiling.
The problem is that the automatic mode automatically changes to on/off,
which implied that the forced on/off modes aren't sticky anymore. It's
annoying when debugging because as soon as the load decreases, profiling
stops.
This makes a small change which ought to have been done first, which
consists in having two states for "auto" (auto-on, auto-off) to
distinguish them from the forced states. Setting to "auto" in the config
defaults to "auto-off" as before, and setting it on the CLI switches to
auto but keeps the current operating state.
This is simple enough to be backported to older releases if needed.
When reporting some values in debugging output we often need to have
some condensed, stable-length values. This function prints a duration
from nanosecond to years with at least 4 digits of accuracy using the
most suitable unit, always on 7 chars.
Do not consider reuse connection if available list is not allocated for
the target server. This will prevent a crash when using a standalone
server for an external purpose like socket_tcp/socket_ssl on hlua code.
For the idle/safe lists, they are considered allocated if
srv.max_idle_conns is not null.
Note that the hlua code is currently safe thanks to the additional
checks on proxy http mode and stream reuse policy not never. However,
this might not be sufficient for future code.
This patch should be backported in every branches containing the
following patch :
7f68d815af (2.4 tree)
REORG: backend: simplify conn_backend_get
This reverts commit 62e8aaa1bd.
While is works extremely well to address SSL handshake floods, it prevents
establishment of new connections during regular traffic above 50-60 Gbps,
because for an unknown reason the queue seems to have ~1.7 active tasks
per connection all the time, which makes no sense as these ought to be
waiting on subscribed events. It might uncover a deeper issue but at least
for now a different solution is needed. cf issue #822.
The test is trivial to run, just start a config with tune.runqueue-depth 10
and inject on 1GB objects with more than 10 connections. Try to connect to
the stats socket, it only works once, then the listeners are not dequeued.
