Both the source file and the dummy library are now at the same place.
Maybe the build howto could be moved there as well to make things even
cleaner.
The Makefile, MAINTAINERS, doc, github build matrix, coverity checks
and travis CI's build were updated.
Now it's much cleaner, both 51d.c and the dummy library live together and
are easier to spot and maintain. The build howto probably ought to be moved
there as well. Makefile, docs and MAINTAINERS were updated, as well as
the github CI's build matrix, travis CI's, and coverity checks.
The following directories were moved from contrib/ to dev/ to make their
use case a bit clearer. In short, only developers are expected to ever
go there. The makefile was updated to build and clean from these ones.
base64/ flags/ hpack/ plug_qdisc/ poll/ tcploop/ trace/
Add a diagnostic to check that two servers of the same backend does not
use the same cookie value. Ignore backup servers as it is quite common
for them to share a cookie value with a primary one.
Define MODE_DIAG which is used to run haproxy in diagnostic mode. This
mode is used to output extra warnings about possible configuration
blunder or sub-optimal usage. It can be activated with argument '-dD'.
A new output function ha_diag_warning is implemented reserved for
diagnostic output. It serves to standardize the format of diagnostic
messages.
A macro HA_DIAG_WARN_COND is also available to automatically check if
diagnostic mode is on before executing the diagnostic check.
In issue #1200 Coverity believes we may use an uninitialized field
smp.sess here while it's not possible because the returned variable
necessarily matches SCOPE_PROC hence smp.sess is not used. But it
cannot see this and it could be confusing if the code later evolved
into something more complex. That's not a critical path so let's
first reset the sample.
A bug was introduced when the legacy HTTP mode was removed. To capture the
HTTP version of the request or the response, we rely on the message state to
be sure the status line was received. However, the test is inverted. The
version can be captured if message headers were received, not the opposite.
This patch must be backported as far as 2.2.
Historically, an option was added to wait for the request payload (option
http-buffer-request). This option has 2 drawbacks. First, it is an ON/OFF
option for the whole proxy. It cannot be enabled on demand depending on the
message. Then, as its name suggests, it only works on the request side. The
only option to wait for the response payload was to write a dedicated
filter. While it is an acceptable solution for complex applications, it is a
bit overkill to simply match strings in the body.
To make everyone happy, this patch adds a dedicated HTTP action to wait for
the message payload, for the request or the response depending it is used in
an http-request or an http-response ruleset. The time to wait is
configurable and, optionally, the minimum payload size to have before stop
to wait.
Both the http action and the old http analyzer rely on the same internal
function.
L6 sample fetches are now ignored when called from an HTTP proxy. Thus, a
warning is emitted during the startup if such usage is detected. It is true
for most ACLs and for log-format strings. Unfortunately, it is a bit painful
to do so for sample expressions.
This patch relies on the commit "MINOR: action: Use a generic function to
check validity of an action rule list".
The check_action_rules() function is now used to check the validity of an
action rule list. It is used from check_config_validity() function to check
L5/6/7 rulesets.
It is not really a context-less sample fetch, but it is internal. And it
only fails if no stream is attached to the sample. This way, it is still
possible to use it on an HTTP proxy (L6 sample fetches are ignored now for
HTTP proxies).
If the commit "BUG/MINOR: payload/htx: Ingore L6 sample fetches for HTX
streams/checks" is backported, it may be a good idea to backport this one
too. But only as far as 2.2.
Use a L6 sample fetch on an HTX streams or a HTX health-check is meaningless
because data are not raw but structured. So now, these sample fetches fail
when called from an HTTP proxy. In addition, a warning has been added in the
configuration manual, at the begining of the L6 sample fetches section.
Note that req.len and res.len samples return the HTX data size instead of
failing. It is not accurate because it does not reflect the buffer size nor
the raw data length. But we keep it for backward compatibility purpose.
However it remains a bit strange to use it on an HTTP proxy.
This patch may be backported to all versions supporting the HTX, i.e as far
as 2.0. But the part about the health-checks is only valid for the 2.2 and
upper.
If a 'switch-mode http' tcp action is configured on a listener with no
backend, a warning is displayed to remember HTTP connections cannot be
routed to TCP servers. Indeed, backend connection is still established using
the proxy mode.
It is now possible to perform HTTP upgrades on a TCP stream from the
frontend side. To do so, a tcp-request content rule must be defined with the
switch-mode action, specifying the mode (for now, only http is supported)
and optionnaly the proto (h1 or h2).
This way it could be possible to set HTTP directives on a TCP frontend which
will only be evaluated if an upgrade is performed. This new way to perform
HTTP upgrades should replace progressively the old way, consisting to route
the request to an HTTP backend. And it should be also a good start to remove
all HTTP processing from tcp-request content rules.
This action is terminal, it stops the ruleset evaluation. It is only
available on proxy with the frontend capability.
The configuration manual has been updated accordingly.
The code responsible to perform an HTTP upgrade from a TCP stream is moved
in a dedicated function, stream_set_http_mode().
The stream_set_backend() function is slightly updated, especially to
correctly set the request analysers.
Now allocation and initialization of HTTP transactions are performed in a
unique function. Historically, there were two functions because the same TXN
was reset for K/A connections in the legacy HTTP mode. Now, in HTX, K/A
connections are handled at the mux level. A new stream, and thus a new TXN,
is created for each request. In addition, the function responsible to end
the TXN is now also reponsible to release it.
So, now, http_create_txn() and http_destroy_txn() must be used to create and
destroy an HTTP transaction.
It is just a small cleanup. AN_REQ_FLT_HTTP_HDRS and AN_RES_FLT_HTTP_HDRS
analysers are now set in HTTP analysers at the same place
AN_REQ_HTTP_XFER_BODY and AN_RES_HTTP_XFER_BODY are set.
We now use the stream instead of the proxy to know if we are processing HTTP
data or not. If the stream is an HTX stream, it means we are dealing with
HTTP data. It is more accurate than the proxy mode because when an HTTP
upgrade is performed, the proxy is not changed and only the stream may be
used.
Note that it was not a problem to rely on the proxy because HTTP upgrades
may only happen when an HTTP backend was set. But, we will add the support
of HTTP upgrades on the frontend side, after te tcp-request rules
evaluation. In this context, we cannot rely on the proxy mode.
Add "none" in the list of supported mux protocols. It relies on the
passthrough multiplexer and use almost the same mux_ops structure. Only the
flags differ because this "new" mux does not support the upgrades. "none"
was chosen to explicitly stated there is not processing at the mux level.
Thus it is now possible to set "proto none" or "check-proto none" on
bind/server lines, depending on the context. However, when set, no upgrade
to HTTP is performed. It may be a way to disable HTTP upgrades per bind
line.
Add "h1" in the list of supported mux protocols. It relies on the H1
multiplexer and use the almost the same mux_ops structure. Only the flags
differ because this "new" mux does not support the upgrades.
Thus it is now possible to set "proto h1" or "check-proto h1" on bind/server
lines, depending on the context. However, when set, no upgrade to HTTP/2 is
performed. It may be a way to disable implicit HTTP/2 upgrades per bind
line.
MX_FL_NO_UPG flag may now be set on a multiplexer to explicitly disable
upgrades from this mux. For now, it is set on the FCGI multiplexer because
it is not supported and there is no upgrade on backend-only multiplexers. It
is also set on the H2 multiplexer because it is clearly not supported.
No warning is emitted if some http-after-response rules are configured on a
TCP proxy while such warning messages are emitted for other HTTP ruleset in
same condition. It is just an oversight.
This patch may be backported as far as 2.2.
When a TCP stream is first upgraded to H1 and then to H2, we must be sure to
inhibit any connect and to properly handle the TCP stream destruction.
When the TCP stream is upgraded to H1, the HTTP analysers are set. Thus
http_wait_for_request() is called. In this case, the server connection must
be blocked, waiting for the request analysis. Otherwise, a server may be
assigned to the stream too early. It is especially a problem if the stream
is finally destroyed because of an implicit upgrade to H2.
In this case, the stream processing must be properly aborted to not have a
stalled stream. Thus, if a shutdown is detected in http_wait_for_request()
when an HTTP upgrade is performed, the stream is aborted.
It is a 2.4-specific bug. No backport is needed.
Always set frontend HTTP analysers when an HTX stream is created. It is only
useful in case a destructive HTTP upgrades (TCP>H2) because the frontend is
a TCP proxy.
In fact, to be strict, we must only set these analysers when the upgrade is
performed before setting the backend (it is not supported yet, but this
patch is required to do so), in the frontend part. If the upgrade happens
when the backend is set, it means the HTTP processing is just the backend
buisness. But there is no way to make the difference when a stream is
created, at least for now.
When an HTX stream is created, be sure to always create the HTTP txn object,
regardless of the ".http_needed" value of the frontend. That happens when a
destructive HTTP upgrades is performed (TCP>H2). The frontend is a TCP
proxy. If there is no dependency on the HTTP part, the HTTP transaction is
not created at this stage but only when the backend is set. For now, it is
not a problem. But an HTTP txn will be mandatory to fully support TCP to
HTTP upgrades after frontend tcp-request rules evaluation.
When a TCP stream is upgraded to H2 stream, a destructive upgrade is
performed. It means the TCP stream is silently released while a new one is
created. It is of course more complicated but it is what we observe from the
stream point of view.
That was performed by returning an error when the backend was set. It is
neither really elegant nor accurate. So now, instead of returning an error
from stream_set_backend() in case of destructive HTTP upgrades, the TCP
stream processing is aborted and no error is reported. However, the result
is more or less the same.
sess_log() was called twice if an error occurred on the preface parsing, in
h2c_frt_recv_preface() and in h2_process_demux().
This patch must be backported as far as 2.0.
The fix in commit 7b0e00d94 ("BUG/MINOR: http_fetch: make hdr_ip() reject
trailing characters") made hdr_ip() more sensitive to empty fields, for
example if a trusted proxy incorrectly sends the header with an empty
value, we could return 0.0.0.0 which is not correct. Let's make sure we
only assign an IPv4 type here when a non-empty address was found.
This should be backported to all branches where the fix above was
backported.
Historically we've used SOL_IP/SOL_IPV6/SOL_TCP everywhere as the socket
level value in getsockopt() and setsockopt() but as we've seen over time
it regularly broke the build and required to have them defined to their
IPPROTO_* equivalent. The Linux ip(7) man page says:
Using the SOL_IP socket options level isn't portable; BSD-based
stacks use the IPPROTO_IP level.
And it indeed looks like a pure linuxism inherited from old examples and
documentation. strace also reports SOL_* instead of IPPROTO_*, which does
not help... A check to linux/in.h shows they have the same values. Only
SOL_SOCKET and other non-IP values make sense since there is no IPPROTO
equivalent.
Let's get rid of this annoying confusion by removing all redefinitions of
SOL_IP/IPV6/TCP and using IPPROTO_* instead, just like any other operating
system. This also removes duplicated tests for the same value.
Note that this should not result in exposing syscalls to other OSes
as the only ones that were still conditionned to SOL_IPV6 were for
IPV6_UNICAST_HOPS which already had an IPPROTO_IPV6 equivalent, and
IPV6_TRANSPARENT which is Linux-specific.
Lukas reported in issue #1203 that the previous fix for silent-drop in
commit ab79ee8b1 ("BUG/MINOR: tcp: fix silent-drop workaround for IPv6")
breaks the build on FreeBSD/MacOS due to SOL_IPV6 not being defined. On
these platforms, IPPROTO_IPV6 must be used instead, so this should fix
it.
This needs to be backported to whatever version the fix above is backported
to.
As reported in github issue #1203 the TTL-based workaround that is used
when permissions are insufficient for the TCP_REPAIR trick does not work
for IPv6 because we're using only SOL_IP with IP_TTL. In IPv6 we have to
use SOL_IPV6 and IPV6_UNICAST_HOPS. Let's pick the right one based on the
source address's family.
This may be backported to all versions.
The issue with non-rotating freq counters was addressed in commit 8cc586c73
("BUG/MEDIUM: freq_ctr/threads: use the global_now_ms variable") using the
global date. But an issue remained with the comparison of the most recent
time. Since the initial time in the structure is zero, the tick_is_lt()
works on half of the periods depending on the first date an entry is
touched. And the wrapping happened last night:
$ date --date=@$(((($(date +%s) * 1000) & -0x8000000) / 1000))
Mon Mar 29 23:59:46 CEST 2021
So users of the last fix (backported to 2.3.8) may experience again an
always increasing rate for the next 24 days if they restart their process.
Let's always update the time if the latest date was not updated yet. It
will likely be simplified once the function is reorganized but this will
do the job for now.
Note that since this timer is only used by freq counters, no other
sub-system is affected. The bug can easily be tested with this config
during the right time period (i.e. today to today+24 days + N*49.7 days):
global
stats socket /tmp/sock1
frontend web
bind :8080
mode http
http-request track-sc0 src
stick-table type ip size 1m expire 1h store http_req_rate(2s)
Issuing 'socat - /tmp/sock1 <<< "show table web"' should show a stable
rate after 2 seconds.
The fix must be backported to 2.3 and any other version the fix above
goes into.
Thanks to Thomas SIMON and Sander Klein for quickly reporting this issue
with a working reproducer.
When a backend is in status DOWN and going UP it is currently displayed
as yellow ("active UP, going down") instead of orange ("active DOWN, going
UP"). This patches restyles the table rows to actually match the
legend.
This may be backported to any version, the issue appeared in 1.7-dev2
with commit 0c378efe8 ("MEDIUM: stats: compute the color code only in
the HTML form").
In payload() and payload_lv() sample fetches, if the buffer is empty, we
must wait for more data by setting SMP_F_MAY_CHANGE flag on the sample.
Otherwise, when it happens in an ACL, nothing is returned (because the
buffer is empty) and the ACL is considered as finished (success or failure
depending on the test).
As a workaround, the buffer length may be tested first. For instance :
tcp-request inspect-delay 1s
tcp-request content reject unless { req.len gt 0 } { req.payload(0,0),fix_is_valid }
instead of :
tcp-request inspect-delay 1s
tcp-request content reject if ! { req.payload(0,0),fix_is_valid }
This patch must be backported as far as 2.2.
Commit b1adf03df ("MEDIUM: backend: use a trylock when trying to grab an
idle connection") solved a contention issue on the backend under normal
condition, but there is another one further, which only happens when the
number of FDs in use is considered too high, and which obviously causes
random crashes with just 16 threads once the number of FDs is about to be
exhausted.
Like the aforementioned patch, this one should be backported to 2.3.
set var <name> <expression>
Allows to set or overwrite the process-wide variable 'name' with the result
of expression <expression>. Only process-wide variables may be used, so the
name must begin with 'proc.' otherwise no variable will be set. The
<expression> may only involve "internal" sample fetch keywords and converters
even though the most likely useful ones will be str('something') or int().
Note that the command line parser doesn't know about quotes, so any space in
the expression must be preceeded by a backslash. This command requires levels
"operator" or "admin". This command is only supported on a CLI connection
running in experimental mode (see "experimental-mode on").
Just like for "set-var" in the global section, the command uses a temporary
dummy proxy to create a temporary "set-var(name)" rule to assign the value.
The reg test was updated to verify that an updated global variable is properly
reflected in subsequent HTTP responses.
Process-wide variables can now be displayed from the CLI using "get var"
followed by the variable name. They must all start with "proc." otherwise
they will not be found. The output is very similar to the one of the
debug converter, with a type and value being reported for the embedded
sample.
This command is limited to clients with the level "operator" or higher,
since it can possibly expose traffic-related data.
In order to process samples from the command line interface we'll need
rules as well, and these rules will have to be marked as coming from
the CLI parser. This new origin is used for this.
In order to prepare for supporting calling sample expressions from the
CLI, let's create a new CLI_PARSER parsing context. This one supports
constants and internal samples only.
While we do support process-wide variables ("proc.<name>"), there was
no way to preset them from the configuration. This was particularly
limiting their usefulness since configs involving them always had to
first check if the variable was set prior to performing an operation.
This patch adds a new "set-var" directive in the global section that
supports setting the proc.<name> variables from an expression, like
other set-var actions do. The syntax however follows what is already
being done for setenv, which consists in having one argument for the
variable name and another one for the expression.
Only "constant" expressions are allowed here, such as "int", "str"
etc, combined with arithmetic or string converters, and variable
lookups. A few extra sample fetch keywords like "date", "rand" and
"uuid" are also part of the constant expressions and may make sense
to allow to create a random key or differentiate processes.
The way it was done consists in parsing a dummy rule an executing the
expression in the CFG_PARSE context, then releasing the expression.
This is safe because the sample that variables store does not hold a
back pointer to expression that created them.
In order to process samples from the config file we'll need rules as
well, and these rules will have to be marked as coming from the
config parser. This new origin is used for this.
We'd sometimes like to be able to process samples while parsing
the configuration based on purely internal thing but that's not
possible right now. Let's add a new CFG_PARSER context for samples
which only permits constant samples (i.e. those which do not change
in the process' life and which are stable during config parsing).
A number of keywords are really constant and safe to use at config
time. This is the case for str(), int() etc but also env(), hostname(),
nbproc() etc. By extension a few other ones which can be useful to
preset values in a configuration were enabled as well, like data(),
rand() or uuid(). At the moment this doesn't change anything as they
are still only usable from runtime rules.
The "var()" keyword was also marked as const as it can definitely
return stable stuff at boot time.
This level indicates that everything it constant in the expression during
the whole process' life and that it may safely be used at config parsing
time.
For now smp_resolve_args() complains on stderr via ha_alert(), but if we
want to make it a bit more dynamic, we need it to return errors in an
allocated message. Let's pass it an error pointer and have it fill it.
On return we indent the output if it contains more than one line.
The "stopping" sample fetch keyword was accidently duplicated in 1.9
by commit 70fe94419 ("MINOR: sample: add cpu_calls, cpu_ns_avg,
cpu_ns_tot, lat_ns_avg, lat_ns_tot"). This has no effect so no
backport is needed.
This sample fetch doesn't require any L4 client session in practice, as
get_var() now checks for the session. This is important to remove this
dependency in order to support accessing variables in scope "proc" from
anywhere.
Instantiate both lua Socket servers tcp/ssl using standard function
new_server. There is currently no need to tune their settings except to
activate the ssl mode with noverify for the second one. Both servers are
freed with the free_server function.
Replace static initialization of the lua Socket proxy with the standard
function alloc_new_proxy. The settings proxy are properly applied thanks
to PR_CAP_LUA. The proxy is freed with the free_proxy function.
Define a new cap PR_CAP_LUA. It can be used to allocate the internal
proxy for lua Socket class. This cap overrides default settings for
preferable values in the lua context.
Move all liberation code related to a proxy in a dedicated function
free_proxy in proxy.c. For now, this function is only called in
haproxy.c. In the future, it will be used to free the lua proxy.
This helps to clean up haproxy.c.
Create a new function parse_new_proxy specifically designed to allocate
a new proxy from the configuration file and copy settings from the
default proxy.
The function alloc_new_proxy is reduced to a minimal allocation. It is
used for default proxy allocation and could also be used for internal
proxies such as the lua Socket proxy.
Move deinit_acl_cond and deinit_act_rules from haproxy.c respectively in
acl.c and action.c. The name of the functions has been slightly altered,
replacing the prefix deinit_* by free_* to reflect their purpose more
clearly.
This change has been made in preparation to the implementation of a free
proxy function. As a side-effect, it helps to clean up haproxy.c.
Create a new module init which contains code related to REGISTER_*
macros for initcalls. init.h is included in api.h to make init code
available to all modules.
It's a step to clean up a bit haproxy.c/global.h.
If the first active line of a crt-list file is also the first mentioned
certificate of a frontend that does not have the strict-sni option
enabled, then its certificate will be used as the default one. We then
do not want this instance to be removable since it would make a frontend
lose its default certificate.
Considering that a crt-list file can be used by multiple frontends, and
that its first mentioned certificate can be used as default certificate
for only a subset of those frontends, we do not want the line to be
removable for some frontends and not the others. So if any of the ckch
instances corresponding to a crt-list line is a default instance, the
removal of the crt-list line will be forbidden.
It can be backported as far as 2.2.
The default SSL_CTX used by a specific frontend is the one of the first
ckch instance created for this frontend. If this instance has SNIs, then
the SSL context is linked to the instance through the list of SNIs
contained in it. If the instance does not have any SNIs though, then the
SSL_CTX is only referenced by the bind_conf structure and the instance
itself has no link to it.
When trying to update a certificate used by the default instance through
a cli command, a new version of the default instance was rebuilt but the
default SSL context referenced in the bind_conf structure would not be
changed, resulting in a buggy behavior in which depending on the SNI
used by the client, he could either use the new version of the updated
certificate or the original one.
This patch adds a reference to the default SSL context in the default
ckch instances so that it can be hot swapped during a certificate
update.
This should fix GitHub issue #1143.
It can be backported as far as 2.2.
In issue #1197, Stphane Graber reported a rare case of crash that
results from an attempt to close an already closed H1 connection. It
indeed looks like under some circumstances it should be possible to
call the h1_shutw_conn() function more than once, though these
conditions are not very clear.
Without going through a deep analysis of all possibilities, one
potential case seems to be a detach() called with pending output data,
causing H1C_F_ST_SHUTDOWN to be set on the connection, then h1_process()
being immediately called on I/O, causing h1_send() to flush these data
and call h1_shutw_conn(), and finally the upper stream calling cs_shutw()
hence h1_shutw(), which itself will call h1_shutw_conn() again while the
transport and control layers have already been released. But the whole
sequence is not certain as it's not very clear in which case it's
possible to leave h1_send() without the connection anymore (at least
the obuf is empty).
However what is certain is that a shutdown function must be idempotent,
so let's fix h1_shutw_conn() regarding this point. Stphane reported the
issue as far back as 2.0, so this patch should be backported this far.
The hdr_ip() sample fetch function will try to extract IP addresses
from a header field. These IP addresses are parsed using url2ipv4()
and if it fails it will fall back to inet_pton(AF_INET6), otherwise
will fail.
There is a small problem there which is that if a field starts with
an IP address and is immediately followed by some garbage, the IP
address part is still returned. This is a problem with fields such
as x-forwarded-for because it prevents detection of accidental
corruption or bug along the chain. For example, the following string:
x-forwarded-for: 1.2.3.4; 5.6.7.8
or this one:
x-forwarded-for: 1.2.3.4O ( the last one being the letter 'O')
would still return "1.2.3.4" despite the trailing characters. This is
bad because it will silently cover broken code running on intermediary
proxies and may even in some cases allow haproxy to pass improperly
formatted headers after they were apparently validated, for example,
if someone extracts the address from this field to place it into
another one.
This issue would only affect the IPv4 parser, because the IPv6 parser
already uses inet_pton() which fails at the first invalid character and
rejects trailing port numbers.
In strict compliance with RFC7239, let's make sure that if there are any
characters left in the string, the parsing fails and makes hdr_ip()
return nothing. However, a special case has to be handled to support
IPv4 addresses followed by a colon and a valid port number, because till
now the parser used to implicitly accept them and it appears that this
practice, though rare, does exist at least in Azure:
https://docs.microsoft.com/en-us/azure/application-gateway/how-application-gateway-works
This issue has always been there so the fix may be backported to all
versions. It will need the following commit in order to work as expected:
MINOR: tools: make url2ipv4 return the exact number of bytes parsed
Many thanks to https://twitter.com/melardev and the BitMEX Security Team
for their detailed report.
The function's return value is currently used as a boolean but we'll
need it to return the number of bytes parsed. Right now it returns
it minus one, unless the last char doesn't match what is permitted.
Let's update this to make it more usable.
If an isolated thread is marked as harmless, it will loop forever in
thread_harmless_till_end() waiting no threads are isolated anymore. It never
happens because the current thread is isolated. To fix the bug, we exclude
the current thread for the test. We now wait for all other threads to leave
the rendez-vous point.
This bug only seems to occurr if HAProxy is compiled with DEBUG_UAF, when
pool_gc() is called. pool_gc() isolates the current thread, while
pool_free_area() set the thread as harmless when munmap is called.
This patch must be backported as far as 2.0.
Release the lock before calling mux destroy in connect_server when
trying to kill an idle connection because the pool high count has been
reached.
The lock must be released because the mux destroy will call
srv_release_conn which also takes the lock to remove the connection from
the tree. As the connection was already deleted from the tree at this
stage, it is safe to release the lock, and the removal in
srv_release_conn will be a noop.
It does not need to be backported because it is only present in the
current release. It has been introduced by
5c7086f6b0
MEDIUM: connection: protect idle conn lists with locks
In fd_delete(), if we're running with no double-width cas, take the
fd_mig_lock before setting thread_mask to 0 to make sure that
another thread calling fd_set_running() won't miss the new value of
thread_mask and set its bit in running_mask after we checked it.
This should be backported to 2.2 as part of the series fixing fd_delete().
Christopher discovered an issue mostly affecting 2.2 and to a less extent
2.3 and above, which is that it's possible to deadlock a soft-stop when
several threads are using a same listener:
thread1 thread2
unbind_listener() fd_set_running()
lock(listener) listener_accept()
fd_delete() lock(listener)
while (running_mask); -----> deadlock
unlock(listener)
This simple case disappeared from 2.3 due to the removal of some locked
operations at the end of listener_accept() on the regular path, but the
architectural problem is still here and caused by a lock inversion built
around the loop on running_mask in fd_clr_running_excl(), because there
are situations where the caller of fd_delete() may hold a lock that is
preventing other threads from dropping their bit in running_mask.
The real need here is to make sure the last user deletes the FD. We have
all we need to know the last one, it's the one calling fd_clr_running()
last, or entering fd_delete() last, both of which can be summed up as
the last one calling fd_clr_running() if fd_delete() calls fd_clr_running()
at the end. And we can prevent new threads from appearing in running_mask
by removing their bits in thread_mask.
So what this patch does is that it sets the running_mask for the thread
in fd_delete(), clears the thread_mask, thus marking the FD as orphaned,
then clears the running mask again, and completes the deletion if it was
the last one. If it was not, another thread will pass through fd_clr_running
and will complete the deletion of the FD.
The bug is easily reproducible in 2.2 under high connection rates during
soft close. When the old process stops its listener, occasionally two
threads will deadlock and the old process will then be killed by the
watchdog. It's strongly believed that similar situations do exist in 2.3
and 2.4 (e.g. if the removal attempt happens during resume_listener()
called from listener_accept()) but if so, they should be much harder to
trigger.
This should be backported to 2.2 as the issue appeared with the FD
migration. It requires previous patches "fd: make fd_clr_running() return
the remaining running mask" and "MINOR: fd: remove the unneeded running
bit from fd_insert()".
Notes for backport: in 2.2, the fd_dodelete() function requires an extra
argument "do_close" indicating whether we want to remove and close the FD
(fd_delete) or just delete it (fd_remove). While this information is not
conveyed along the chain, we know that late calls always imply do_close=1
become do_close=0 exclusively results from fd_remove() which is only used
by the config parser and the master, both of which are single-threaded,
hence are always the last ones in the running_mask. Thus it is safe to
assume that a postponed FD deletion always implies do_close=1.
Thanks to Olivier for his help in designing this optimal solution.
When a lua context is allocated, its stack must be initialized to NULL
before attaching it to its owner (task, stream or applet). Otherwise, if
the watchdog is fired before the stack is really created, that may lead to a
segfault because we try to dump the traceback of an uninitialized lua stack.
It is easy to trigger this bug if a lua script do a blocking call while
another thread try to initialize a new lua context. Because of the global
lua lock, the init is blocked before the stack creation. Of course, it only
happens if the script is executed in the shared global context.
This patch must be backported as far as 2.0.
The commit reverts following commits:
* 83926a04 BUG/MEDIUM: debug/lua: Don't dump the lua stack if not dumpable
* a61789a1 MEDIUM: lua: Use a per-thread counter to track some non-reentrant parts of lua
Instead of relying on a Lua function to print the lua traceback into the
debugger, we are now using our own internal function (hlua_traceback()).
This one does not allocate memory and use a chunk instead. This avoids any
issue with a possible deadlock in the memory allocator because the thread
processing was interrupted during a memory allocation.
This patch relies on the commit "BUG/MEDIUM: debug/lua: Use internal hlua
function to dump the lua traceback". Both must be backported wherever the
patches above are backported, thus as far as 2.0
The separator string is now configurable, passing it as parameter when the
function is called. In addition, the message have been slightly changed to
be a bit more readable.
If an unknown CA file was first mentioned in an "add ssl crt-list" CLI
command, it would result in a call to X509_STORE_load_locations which
performs a disk access which is forbidden during runtime. The same would
happen if a "ca-verify-file" or "crl-file" was specified. This was due
to the fact that the crt-list file parsing and the crt-list related CLI
commands parsing use the same functions.
The patch simply adds a new parameter to all the ssl_bind parsing
functions so that they know if the call is made during init or by the
CLI, and the ssl_store_load_locations function can then reject any new
cafile_entry creation coming from a CLI call.
It can be backported as far as 2.2.
Previous commit 69ba35146 ("MINOR: tools: introduce new option
PA_O_DEFAULT_DGRAM on str2sa_range.") managed to introduce a
parenthesis imbalance that broke the build. No backport is needed.
str2sa_range function options PA_O_DGRAM and PA_O_STREAM are used to
define the supported address types but also to set the default type
if it is not explicit. If the used address support both STREAM and DGRAM,
the default was always set to STREAM.
This patch introduce a new option PA_O_DEFAULT_DGRAM to force the
default to DGRAM type if it is not explicit in the address field
and both STREAM and DGRAM are supported. If only DGRAM or only STREAM
is supported, it continues to be considered as the default.
In commit a1ecbca0a ("BUG/MINOR: freq_ctr/threads: make use of the last
updated global time"), for period-based counters, the millisecond part
of the global_now variable was used as the date for the new period. But
it's wrong, it only works with sub-second periods as it wraps every
second, and for other periods the counters never rotate anymore.
Let's make use of the newly introduced global_now_ms variable instead,
which contains the global monotonic time expressed in milliseconds.
This patch needs to be backported wherever the patch above is backported.
It depends on previous commit "MINOR: time: also provide a global,
monotonic global_now_ms timer".
The period-based freq counters need the global date in milliseconds,
so better calculate it and expose it rather than letting all call
places incorrectly retrieve it.
Here what we do is that we maintain a new globally monotonic timer,
global_now_ms, which ought to be very close to the global_now one,
but maintains the monotonic approach of now_ms between all threads
in that global_now_ms is always ahead of any now_ms.
This patch is made simple to ease backporting (it will be needed for
a subsequent fix), but it also opens the way to some simplifications
on the time handling: instead of computing the local time and trying
to force it to the global one, we should soon be able to proceed in
the opposite way, that is computing the new global time an making the
local one just the latest snapshot of it. This will bring the benefit
of making sure that the global time is always ahead of the local one.
The function's purpose used to be to fail a buffer allocation if that
allocation wouldn't result in leaving some buffers available. Thus,
some allocations could succeed and others fail for the sole purpose of
trying to provide 2 buffers at once to process_stream(). But things
have changed a lot with 1.7 breaking the promise that process_stream()
would always succeed with only two buffers, and later the thread-local
pool caches that keep certain buffers available that are not accounted
for in the global pool so that local allocators cannot guess anything
from the number of currently available pools.
Let's just replace all last uses of b_alloc_margin() with b_alloc() once
for all.
pool_alloc_dirty() is the version below pool_alloc() that never performs
the memory poisonning. It should only be called directly for very large
unstructured areas for which enabling memory poisonning would not bring
anything but could significantly hurt performance (e.g. buffers). Using
this function here will not provide any benefit and will hurt the ability
to debug.
It would be desirable to backport this, although it does not cause any
user-visible bug, it just complicates debugging.
pool_alloc_dirty() is the version below pool_alloc() that never performs
the memory poisonning. It should only be called directly for very large
unstructured areas for which enabling memory poisonning would not bring
anything but could significantly hurt performance (e.g. buffers). Using
this function here will not provide any benefit and will hurt the ability
to debug.
It would be desirable to backport this, although it does not cause any
user-visible bug, it just complicates debugging.
pool_alloc_dirty() is the version below pool_alloc() that never performs
the memory poisonning. It should only be called directly for very large
unstructured areas for which enabling memory poisonning would not bring
anything but could significantly hurt performance (e.g. buffers). Using
this function here will not provide any benefit and will hurt the ability
to debug.
It would be desirable to backport this, although it does not cause any
user-visible bug, it just complicates debugging.
pool_alloc_dirty() is the version below pool_alloc() that never performs
the memory poisonning. It should only be called directly for very large
unstructured areas for which enabling memory poisonning would not bring
anything but could significantly hurt performance (e.g. buffers). Using
this function here will not provide any real benefit, it only avoids the
area being poisonned before being zeroed. Ideally a pool_calloc() function
should be provided for this.
pool_alloc_dirty() is the version below pool_alloc() that never performs
the memory poisonning. It should only be called directly for very large
unstructured areas for which enabling memory poisonning would not bring
anything but could significantly hurt performance (e.g. buffers). Using
this function here will not provide any benefit and will hurt the ability
to debug.
It would be desirable to backport this, although it does not cause any
user-visible bug, it just complicates debugging.
This fixes a gcc warning about a missing const on defproxy for
mem_parse_global_fail_alloc.
This is needed since the commit :
018251667e
CLEANUP: config: make the cfg_keyword parsers take a const for the
defproxy
When we try to dump the stack of a lua context, if it is not dumpable,
nothing is performed and a message is emitted instead. This happens when a
lua execution was interrupted inside a non-reentrant part.
This patch depends on following commit :
* MEDIUM: lua: Use a per-thread counter to track some non-reentrant parts of lua
Thanks to this patch, we avoid a possible deadllock if the lua is
interrupted by the watchdog in the lua memory allocator, because realloc()
is not async-signal-safe.
Both patches must be backported as far as 2.0.
Some parts of the Lua are non-reentrant. We must be sure to carefully track
these parts to not dump the lua stack when it is interrupted inside such
parts. For now, we only identified the custom lua allocator. If the thread
is interrupted during the memory allocation, we must not try to print the
lua stack wich also allocate memory. Indeed, realloc() is not
async-signal-safe.
In this patch we introduce a thread-local counter. It is incremented before
entering in a non-reentrant part and decremented when exiting. It is only
performed in hlua_alloc() for now.
It was misspelled (expect-netscaler-ip instead of expect-netscaler-cip). 2
commits are concerned :
* db67b0ed7 MINOR: tcp-rules: suggest approaching action names on mismatch
* 72d012fbd CLEANUP: tcp-rules: add missing actions in the tcp-request error message
The first one will not be backported, but the second one was backported as
far as 1.8. Thus this one may also be backported, but only the 2nd part
about the list of accepted keywords.
Now that connections aren't being reused when they failed, remove the
reset() method. It was unimplemented anywhere, except for H1 where it did
nothing, anyway.
Add a start() method to ssl_sock. It is responsible with initiating the
SSL handshake, currently by just scheduling the tasklet, instead of doing
it in the init() method, when all the XPRT may not have been initialized.
Add a start_method to xprt_handshake. It schedules the tasklet that does
the handshake. This used to be done in xprt_handshake_add_xprt(), but that's
a much better place.
Introduce a new XPRT method, start(). The init() method will now only
initialize whatever is needed for the XPRT to run, but any action the XPRT
has to do before being ready, such as handshakes, will be done in the new
start() method. That way, we will be sure the full stack of xprt will be
initialized before attempting to do anything.
The init() call is also moved to conn_prepare(). There's no longer any reason
to wait for the ctrl to be ready, any action will be deferred until start(),
anyway. This means conn_xprt_init() is no longer needed.
The proto "uxdg" (UNIX DGRAM) was not declared, causing an error trying
to put a socket unix on "dgram-bind" into a log-forward section.
This patch introduces the missing "uxdg" protocol by adding proto_uxdg.c
which was fully created based on the code available for the other
protocols.
This patch should be backported to version 2.3 and above.
Allow to specify the mux proto for a dynamic server. It must be
compatible with the backend mode to be accepted. The reg-tests has been
extended for this error case.
Enable a subset of server options to be used as keywords on the CLI
command 'add server'. These options are safe and can be applied
flawlessly for a dynamic server.
Add a new cli command 'add server'. This command is used to create a new
server at runtime attached on an existing backend. The syntax is the
following one :
$ add server <be_name>/<sv_name> [<kws>...]
This command is only available through experimental mode for the moment.
Currently, no server keywords are supported. They will be activated
individually when deemed properly functional and safe.
Another limitation is put on the backend load-balancing algorithm. The
algorithm must use consistent hashing to guarantee a minimal
reallocation of existing connections on the new server insertion.
Remove static qualifier on stats_allocate_proxy_counters_internal. This
function will be used to allocate extra counters at runtime for dynamic
servers.
Prepare the server parsing API to support dynamic servers.
- define a new parsing flag to be used for dynamic servers
- each keyword contains a new field dynamic_ok to indicate if it can be
used for a dynamic server. For now, no keyword are supported.
- do not copy settings from the default server for a new dynamic server.
- a dynamic server is created in a maintenance mode and requires an
explicit 'enable server' command.
- a new server flag named SRV_F_DYNAMIC is created. This flag is set for
all servers created at runtime. It might be useful later, for example
to know if a server can be purged.
Modify the API of parse_server function. Use flags to describe the type
of the parsed server instead of discrete arguments. These flags can be
used to specify if a server/default-server/server-template is parsed.
Additional parameters are also specified (parsing of the address
required, resolve of a name must be done immediately).
It is now unneeded to use strcmp on args[0] in parse_server. Also, the
calls to parse_server are more explicit thanks to the flags.
Move server linked into proxy backend list outside of _srv_parse_init to
parse_server.
This is groundwork for dynamic servers support. There will be two
differences in case of a dynamic server :
- the server will be attached to the proxy list only at the very end of the
operations when everything is ok
- the server will be directly attached to the end of the server proxy
list
Move every ha_alert calls in parsing functions into parse_server.
Parsing functions now support a pointer-to-string argument which will be
allocated with an error message if needed via memprintf.
parse_server has then the responsibility to display errors with ha_alert.
This is groundwork for dynamic server. No traces should be printed on
stderr as a response to a cli command. cli_err will replace ha_alert in
this case.
The huge parse_server function is splitted into two smaller ones.
* _srv_parse_init allocates a new server instance and parses the address
parameter
* _srv_parse_kw parse the current server keyword
This simplify a bit the parse_server function. Besides, it will be
useful for dynamic server creation.
Move server-keyword hardcoded in parse_server into the srv_kws list of
server.c. Now every server keywords is checked through srv_find_kw. This
has the effect to reduce the size of parse_server. As a side-effect,
common kw list can be reduced.
This change has been made to be able to quickly discard these keywords
in case of a dynamic server.
The idle conn task is is a global task used to cleanup backend
connections marked for deletion. Previously, it was only only allocated
if at least one server in the configuration has idle connections.
This assumption won't be valid anymore when new servers can be created
at runtime with idle connections. Always allocate the global idle conn
task.
Declaring a master CLI socket without activating the master-worker mode
is likely a user error, so we issue a warning.
This patch can be backported as far as 1.8.
If the configuration file contains a 'unix-bind prefix' directive, and
if we use the -S option and specify a UNIX socket path, the path of the
socket will be prepended with the value of the unix-bind prefix.
For instance, if we have 'unix-bind prefix /tmp/sockets/' and we use
'-S /tmp/master-socket' on the command line, we will get this error:
Starting proxy MASTER:
cannot bind UNIX socket (No such file or directory) [/tmp/sockets/tmp/master-socket]
So this patch adds an exception, and will ignore the unix-bind prefix
for the master CLI socket.
This patch can be backported as far as 1.9.
The freq counters were using the thread's own time as the start of the
current period. The problem is that in case of contention, it was
occasionally possible to perform non-monotonic updates on the edge of
the next second, because if the upfront thread updates a counter first,
it causes a rotation, then the second thread loses the race from its
older time, and tries again, and detects a different time again, but
in the past so it only updates the counter, then a third thread on the
new date would detect a change again, thus provoking a rotation again.
The effect was triple:
- rare loss of stored values during certain transitions from one
period to the next one, causing counters to report 0
- half of the threads forced to go through the slow path every second
- difficult convergence when using many threads where the CAS can fail
a lot and we can observe N(N-1) attempts for N threads to complete
This patch fixes this issue in two ways:
- first, it now makes use og the monotonic global_now value which also
happens to be volatile and to carry the latest known time; this way
time will never jump backwards anymore and only the first thread
updates it on transition, the other ones do not need to.
- second, re-read the time in the loop after each failure, because
if the date changed in the counter, it means that one thread knows
a more recent one and we need to update. In this case if it matches
the new current second, the fast path is usable.
This patch relies on previous patch "MINOR: time: export the global_now
variable" and must be backported as far as 1.8.
This is the process-wide monotonic time that is used to update each
thread's own time. It may be required at a few places where a strictly
monotonic clock is required such as freq_ctr. It will be have to be
backported as a dependency of a forthcoming fix.
DNS hostname comparisons were fixed to be case-insensitive (see b17b88487
"BUG/MEDIUM: dns: Consider the fact that dns answers are
case-insensitive"). However 2 comparisons are still case-sensitive.
This patch must be backported as far as 1.8.
Some are not always easy to spot with "chk" vs "check" or hyphens at
some places and not at others. Now entering "option http-close" properly
suggests "httpclose" and "option tcp-chk" suggests "tcp-check". There's
no need to consider the proxy's capabilities, what matters is to figure
what related word the user tried to spell, and there are not that many
options anyway.
Now the suggested keywords are sorted with the most relevant ones first
instead of scanning them all in registration order and only dumping the
proposed ones:
- "tra"
trace <module> [cmd [args...]] : manage live tracing
operator : lower the level of the current CLI session to operator
user : lower the level of the current CLI session to user
show trace [<module>] : show live tracing state
- "pool"
show pools : report information about the memory pools usage
add acl : add acl entry
del map : delete map entry
user : lower the level of the current CLI session to user
del acl : delete acl entry
- "sh ta"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show tasks : show running tasks
set table [id] : update or create a table entry's data
show table [id]: report table usage stats or dump this table's contents
trace <module> [cmd [args...]] : manage live tracing
- "sh state"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
set table [id] : update or create a table entry's data
show table [id]: report table usage stats or dump this table's contents
show servers state [id]: dump volatile server information (for backend <id>)
show sess [id] : report the list of current sessions or dump this session
Till now the fuzzy matching would only work on the same number of words,
but this doesn't account for commands like "show servers conn" which
involve 3 words and were not proposed when entering only "show conn".
Let's improve the situation by building the two fingerprints separately
for the correct keyword sequence and the entered one, then compare them.
This can result in slightly larger variations due to the different string
lengths but is easily compensated for. Thanks to this, we can now see
"show servers conn" when entering "show conn", and the following choices
are relevant to correct typos:
- "show foo"
show sess [id] : report the list of current sessions or dump this session
show info : report information about the running process [desc|json|typed]*
show env [var] : dump environment variables known to the process
show fd [num] : dump list of file descriptors in use
show pools : report information about the memory pools usage
- "show stuff"
show sess [id] : report the list of current sessions or dump this session
show info : report information about the running process [desc|json|typed]*
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show fd [num] : dump list of file descriptors in use
show tasks : show running tasks
- "show stafe"
show sess [id] : report the list of current sessions or dump this session
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show fd [num] : dump list of file descriptors in use
show table [id]: report table usage stats or dump this table's contents
show tasks : show running tasks
- "show state"
show stat : report counters for each proxy and server [desc|json|no-maint|typed|up]*
show servers state [id]: dump volatile server information (for backend <id>)
It's still visible that the shorter ones continue to easily match, such
as "show sess" not having much in common with "show foo" but what matters
is that the best candidates are definitely relevant. Probably that listing
them in match order would further help.
While sums of squares usually give excellent results in fixed-sise
patterns, they don't work well to compare different sized ones such
as when some sub-words are missing, because a word such as "server"
contains "er" twice, which will rsult in an extra distance of at
least 4 for just this e->r transition compared to another one missing
it. This is one of the main reasons why "show conn" only proposes
"show info" on the CLI. Maybe an improved approach consisting in
using squares only for exact same lengths would work, but it would
still make it difficult to spot reversed characters.
The distance between two words can be high due to a sub-word being missing
and in this case it happens that other totally unrealted words are proposed
because their average score looks lower thanks to being shorter. Here we're
introducing the notion of presence of each character so that word sequences
that contain existing sub-words are favored against the shorter ones having
nothing in common. In addition we do not distinguish being/end from a
regular delimitor anymore. That made it harder to spot inverted words.
In commit a0e8eb8ca ("MINOR: cfgparse: suggest correct spelling for
unknown words in global section") we got the ability to locate a better
matching word in case of error. But it mistakenly used the CFG_LISTEN
class of words instead of CFG_GLOBAL, resulting in proposing unsuitable
matches in addition to the long hard-coded list. Now, "tune.dh-param"
correctly proposes "tune.ssl.default-dh-param".
No backport is needed.
I somehow managed to re-break the "help" command in b736458bf ("MEDIUM:
cli: apply spelling fixes for known commands before listing them")
after fixing it once. A null-deref happens when checking the args
early in the processing.
No backport is needed as this was introduced in 2.4-dev12.
When tasklets were derived from tasks, there was no immediate need for
the scheduler to know their status after execution, and in a spirit of
simplicity they just started to always return NULL. The problem is that
it simply prevents the scheduler from 1) accounting their execution time,
and 2) keeping track of their current execution status. Indeed, a remote
wake-up could very well end up manipulating a tasklet that's currently
being executed. And this is the reason why those handlers have to take
the idle lock before checking their context.
In 2.5 we'll take care of making tasklets and tasks work more similarly,
but trouble is to be expected if we continue to propagate the trend of
returning NULL everywhere, especially if some fixes relying on a stricter
model later need to be backported. For this reason this patch updates all
known tasklet handlers to make them return NULL only when the tasklet was
freed. It has no effect for now and isn't even guaranteed to always be
100% safe but it puts the code into the right direction for this.
There were still a very small list of functions, variables and fields
called "stats_" while they were really purely CLI-centric. There's the
frontend called "stats_fe" in the global section, which instantiates a
"cli_applet" called "<CLI>" so it was renamed "cli_fe".
The "alloc_stats_fe" function cas renamed to "cli_alloc_fe" which also
better matches the naming convention of all cli-specific functions.
Finally the "stats_permission_denied_msg" used to return an error on
the CLI was renamed "cli_permission_denied_msg".
Now there's no more "stats_something" that designates the CLI.
This is the number of args accepted on a command received on the CLI,
is has long been totally independent of stats and should not carry
this misleading "stats" name anymore.
Now instead of comparing words at an exact position, we build a fingerprint
made of all of them, so that we can check for them in any position. For
example, "show conn serv" finds "show servers conn" and that "set servers
maxconn" proposes both "set server" and "set maxconn servers".
Instead of making a new one from scratch, let's support not wiping the
existing fingerprint and updating it, and to do the same char by char.
The word-by-word one will still result in multiple beginnings and ends,
but that will accurately translate word boundaries. The char-based one
has more flexibility and requires that the caller maintains the previous
char to indicate the transition, which also allows to insert delimiters
for example.
Entering "show tls" would still emit 35 entries. By measuring the distance
between all unknown words and the candidates, we can sort them and pick the
10 most likely candidates. This works reasonably well, as now "show tls"
only proposes "show tls-keys", "show threads", "show pools" and "show tasks".
If the distance is still too high or if a word is missing, the whole
prefix list continues to be dumped, thus "show" alone will still report
the entire list of commands beginning with "show".
It's still impossible to skip a word, for example "show conn" will not
propose "show servers conn" because the distance is calculated for each
word individually. Some changes to the distance calculation to support
updating an existing map could easily address this. But this is already
a great improvement.
The error message on the CLI has become unreadable due to the long list
and it's not even sorted, making it even harder to figure the right
command.
This patch starts by looking if some of the words match something known,
and if so, will limit the listing only to those commands that start like
the current one. The "help", "prompt" and "quit" commands are always
shown to help the user try something else. Now thanks to this, typing
"add" or "del" will only list "add acl", "add map" and not 50 lines
anymore.
As a small bonus, we won't print "Unknown command" anymore in response
to the "help" command.
By doing so we can report more accurate information about what's wrong.
As a first step, we already distinguish the case of expert-only commands
from other ones.
Now that the appctx contains the master level, it greatly simplifies
all the tests, as we can simply verify that keyword levels match the
effective level without having to cheat with applet pointers. This
also allows to fold the expert test in them.
Right now the code is a bit hackish, it tests for the keyword's level
flags but checks the applet's origin to compare the bits. Let's start
by properly setting the ACCESS_MASTER_ONLY and ACCESS_MASTER flags on
the master CLI's bind_conf so that they are automatically present
all the time.
These 3 commands are functionally valid both in master and worker CLIs.
However, while they do have a valid handler, they are not permitted by
the code and work partially by chance in the master:
- "prompt" and "quit" are intercepted by the request analyser
- "help" triggers an error, which results in displaying the error
message
Let's make sure they are permitted so that we don't count errors there and
that we can report appropriate help.
This bug has always been there but it doesn't have any functional effect
at the moment since "help" can only show the error message. As such, there
is no need to backport it.
The loop looking for existing ADD items to renew their last_seen must ignore
the items already renewed in the same loop. To do so, we rely on the
last_seen time. because it is now based on now_ms, it is safe.
Doing so avoid to match several time the same ADD item when the same IP
address is found in several ADD item. This reduces the number of extra DNS
resolutions.
This patch depends on "MINOR: resolvers: Use milliseconds for cached items
in resolver responses". Both may be backported as far as 2.2 if necessary.
The last time when an item was seen in a resolver responses is now stored in
milliseconds instead of seconds. This avoid some corner-cases at the
edges. This also simplifies time comparisons.
At startup, if a SRV resolution is set for a server, no DNS resolution is
created. We must wait the first SRV resolution to know if it must be
triggered. It is important to do so for two reasons.
First, during a "classical" startup, a server based on a SRV resolution has
no hostname. Thus the created DNS resolution is useless. Best waiting the
first SRV resolution. It is not really a bug at this stage, it is just
useless.
Second, in the same situation, if the server state is loaded from a file,
its hosname will be set a bit later. Thus, if there is no additionnal record
for this server, because there is already a DNS resolution, it inhibits any
new DNS resolution. But there is no hostname attached to the existing DNS
resolution. So no resolution is performed at all for this server.
To avoid any problem, it is fairly easier to handle this special case during
startup. But this means we must be prepared to have no "resolv_requester"
field for a server at runtime.
This patch must be backported as far as 2.2.
Another way to say it: "Safely unlink requester from a requester callbacks".
Requester callbacks must never try to unlink a requester from a resolution, for
the current requester or another one. First, these callback functions are called
in a loop on a request list, not necessarily safe. Thus unlink resolution at
this place, may be unsafe. And it is useless to try to make these loops safe
because, all this stuff is placed in a loop on a resolution list. Unlink a
requester may lead to release a resolution if it is the last requester.
However, the unkink is necessary because we cannot reset the server state
(hostname and IP) with some pending DNS resolution on it. So, to workaround
this issue, we introduce the "safe" unlink. It is only performed from a
requester callback. In this case, the unlink function never releases the
resolution, it only reset it if necessary. And when a resolution is found
with an empty requester list, it is released.
This patch depends on the following commits :
* MINOR: resolvers: Purge answer items when a SRV resolution triggers an error
* MINOR: resolvers: Use a function to remove answers attached to a resolution
* MINOR: resolvers: Directly call srvrq_update_srv_state() when possible
* MINOR: resolvers: Add function to change the srv status based on SRV resolution
All the series must be backported as far as 2.2. It fixes a regression
introduced by the commit b4badf720 ("BUG/MINOR: resolvers: new callback to
properly handle SRV record errors").
don't release resolution from requester cb
When the server status must be updated from the result of a SRV resolution,
we can directly call srvrq_update_srv_state(). It is simpler and this avoid
a test on the server DNS resolution.
This patch is mandatory for the next commit. It also rely on "MINOR:
resolvers: Directly call srvrq_update_srv_state() when possible".
srvrq_update_srv_status() update the server status based on result of SRV
resolution. For now, it is only used from snr_update_srv_status() when
appropriate.
When a SRV request trigger an error, if we decide to handle the error
because last_valid duration is expired, the answer list may be purged. All
items are considered as obsolete.
resolv_purge_resolution_answer_records() must be used to removed all answers
attached to a resolution. For now, it is only used when a resolution is
released.
When a ADD item attached to a SRV item is removed because it is obsolete, we
must trigger a DNS resolution to be sure the hostname still resolves or
not. There is no other way to be the entry is still valid. And we cannot set
the server in RMAINT immediatly, because a DNS server may be inconsitent and
may stop to add some additionnal records.
The opposite is also true. If a valid ADD item is still attached to a SRV
item, any DNS resolution must be stopped. There is no reason to perform
extra resolution in this case.
This patch must be backported as far as 2.2.
If no ADD item is found for a SRV item in a SRV response, a DNS resolution
is triggered. When it succeeds, we must be sure the SRV item is still
alive. Otherwise the DNS resolution must be ignored.
This patch depends on the commit "MINOR: resolvers: Move last_seen time of
an ADD into its corresponding SRV item". Both must be backported as far as
2.2.
This function search for a SRV answer item associated to a requester
whose type is server.
This is mainly useful to "link" a server to its SRV record when no
additional record were found to configure the IP address.
This patch is required by a bug fix.
For each ADD item found in a SRV response, we try to find a corresponding
ADD item already attached to an existing SRV item. If found, the ADD
last_seen time is updated, otherwise we try to find a SRV item with no ADD
to attached the new one.
However, the loop is buggy. Instead of comparing 2 ADD items, it compares
the new ADD item with the SRV item. Because of this bug, we are unable to
renew last_seen time of existing ADD.
This patch must be backported as far as 2.2.
when a server status is updated based on a SRV item, it is always set to UP,
regardless it has an IP address defined or not. For instance, if only a SRV
item is received, with no additional record, only the server hostname is
defined. We must wait to have an IP address to set the server as UP.
This patch must be backported as far as 2.2.
When a server is set in RMAINT becaues of a SRV resolution failure, the
server DNS resolution, if any, must be unlink first. It is mandatory to
handle the change in the context of a SRV resolution.
This patch must be backported as far as 2.2.
When a DNS resolution error is detected, in snr_resolution_error_cb(), the
server address must be reset only if the server status has changed. It this
case, it means the server is set to RMAINT. Thus the server address may by
reset.
This patch fixes a bug introduced by commit d127ffa9f ("BUG/MEDIUM:
resolvers: Reset address for unresolved servers"). It must be backported as
far as 2.0.
When an error is received for a DNS resolution, for instance a NXDOMAIN
error, the server must be considered to have no address when its status is
updated, not the opposite.
Concretly, because this parameter is not used on error path in
snr_update_srv_status(), there is no impact.
This patch must be backported as far as 1.8.
This reverts commit a331a1e8eb.
This commit fixes a real bug, but it also reveals some hidden bugs, mostly
because of some design issues. Thus, in itself, it create more problem than
it solves. So revert it for now. All known bugs will be addressed in next
commits.
This patch should be backported as far as 2.2.
This was introduced in previous commit 49c2b45c1 ("MINOR: cfgparse/server:
try to fix spelling mistakes on server lines"), the loop was changed but
the increment left. No backport is needed.
This adds support for action_suggest() in http-request, http-response
and http-after-response rulesets. For example:
parsing [/dev/stdin:2]: 'http-request' expects (...), but got 'del-hdr'. Did you mean 'del-header' maybe ?
action_suggest() will return a pointer to an action whose keyword more or
less ressembles the passed argument. It also accepts to be more tolerant
against prefixes (since actions taking arguments are handled as prefixes).
This will be used to suggest approaching words.
Just like with the server keywords, now's the turn of "bind" keywords.
The difference is that 100% of the bind keywords are registered, thus
we do not need the list of extra keywords.
There are multiple bind line parsers today, all were updated:
- peers
- log
- dgram-bind
- cli
$ printf "listen f\nbind :8000 tcut\n" | ./haproxy -c -f /dev/stdin
[NOTICE] 070/101358 (25146) : haproxy version is 2.4-dev11-7b8787-26
[NOTICE] 070/101358 (25146) : path to executable is ./haproxy
[ALERT] 070/101358 (25146) : parsing [/dev/stdin:2] : 'bind :8000' unknown keyword 'tcut'; did you mean 'tcp-ut' maybe ?
[ALERT] 070/101358 (25146) : Error(s) found in configuration file : /dev/stdin
[ALERT] 070/101358 (25146) : Fatal errors found in configuration.
Let's apply the fuzzy match to server keywords so that we can avoid
dumping the huge list of supported keywords each time there is a spelling
mistake, and suggest proper spelling instead:
$ printf "listen f\nserver s 0 sendpx-v2\n" | ./haproxy -c -f /dev/stdin
[NOTICE] 070/095718 (24152) : haproxy version is 2.4-dev11-caa6e3-25
[NOTICE] 070/095718 (24152) : path to executable is ./haproxy
[ALERT] 070/095718 (24152) : parsing [/dev/stdin:2] : 'server s' unknown keyword 'sendpx-v2'; did you mean 'send-proxy-v2' maybe ?
[ALERT] 070/095718 (24152) : Error(s) found in configuration file : /dev/stdin
[ALERT] 070/095718 (24152) : Fatal errors found in configuration.
The global section also knows a large number of keywords that are not
referenced in any list, so this needed them to be specifically listed.
It becomes particularly handy now because some tunables are never easy
to remember, but now it works remarkably well:
$ printf "global\nsched.queue_depth\n" | ./haproxy -c -f /dev/stdin
[NOTICE] 070/093007 (23457) : haproxy version is 2.4-dev11-dd8ee5-24
[NOTICE] 070/093007 (23457) : path to executable is ./haproxy
[ALERT] 070/093007 (23457) : parsing [/dev/stdin:2] : unknown keyword 'sched.queue_depth' in 'global' section; did you mean 'tune.runqueue-depth' maybe ?
[ALERT] 070/093007 (23457) : Error(s) found in configuration file : /dev/stdin
[ALERT] 070/093007 (23457) : Fatal errors found in configuration.
Let's start by the largest keyword list, the listeners. Many keywords were
still not part of a list, so a common_kw_list array was added to list the
not enumerated ones. Now for example, typing "tmout" properly suggests
"timeout":
$ printf "frontend f\ntmout client 10s\n" | ./haproxy -c -f /dev/stdin
[NOTICE] 070/091355 (22545) : haproxy version is 2.4-dev11-3b728a-21
[NOTICE] 070/091355 (22545) : path to executable is ./haproxy
[ALERT] 070/091355 (22545) : parsing [/dev/stdin:2] : unknown keyword 'tmout' in 'frontend' section; did you mean 'timeout' maybe ?
[ALERT] 070/091355 (22545) : Error(s) found in configuration file : /dev/stdin
[ALERT] 070/091355 (22545) : Fatal errors found in configuration.
Instead of just reporting "unknown keyword", let's provide a function which
will look through a list of registered keywords for a similar-looking word
to the one that wasn't matched. This will help callers suggest correct
spelling. Also, given that a large part of the config parser still relies
on a long chain of strcmp(), we'll need to be able to pass extra candidates.
Thus the function supports an optional extra list for this purpose.
This introduces two functions, one which creates a fingerprint of a word,
and one which computes a distance between two words fingerprints. The
fingerprint is made by counting the transitions between one character and
another one. Here we consider the 26 alphabetic letters regardless of
their case, then any digit as a digit, and anything else as "other". We
also consider the first and last locations as transitions from begin to
first char, and last char to end. The distance is simply the sum of the
squares of the differences between two fingerprints. This way, doubling/
missing a letter has the same cost, however some repeated transitions
such as "e"->"r" like in "server" are very unlikely to match against
situations where they do not exist. This is a naive approach but it seems
to work sufficiently well for now. It may be refined in the future if
needed.
The error message for http-request and http-response starts with a comma
that very likely is a leftover from a previous list construct. Let's remove
it: "'http-request' expects , 'wait-for-handshake', 'use-service' ...".
The error message after "http-response set-var" isn't very clear:
[ALERT] 070/115043 (30526) : parsing [/dev/stdin:2] : error detected in proxy 'f' while parsing 'http-response set-var' rule : invalid variable 'set-var'. Expects 'set-var(<var-name>)' or 'unset-var(<var-name>)'.
Let's change it to this instead:
[ALERT] 070/115608 (30799) : parsing [/dev/stdin:2] : error detected in proxy 'f' while parsing 'http-response set-var' rule : invalid or incomplete action 'set-var'. Expects 'set-var(<var-name>)' or 'unset-var(<var-name>)'.
With a wrong action name, it also works better (it's handled as a prefix
due to the opening parenthesis):
[ALERT] 070/115608 (30799) : parsing [/dev/stdin:2] : error detected in proxy 'f' while parsing 'http-response set-varxxx' rule : invalid or incomplete action 'set-varxxx'. Expects 'set-var(<var-name>)' or 'unset-var(<var-name>)'.
The tcp-request error message only mentions "accept", "reject" and
track-sc*, but there are a few other ones that were missing, so let's
add them.
This could be backported, though it's not likely that it will help anyone
with an existing config.
The refactoring in commit 131b07be3 ("MEDIUM: server: Refactor
apply_server_state() to make it more readable") also had a copy-paste
error resulting in using global.server_state_file instead of the
function's argument, which easily crashes with a conf having a
state file in a backend and no global state file.
In addition, let's simplify the code and get rid of strcpy() which
almost certainly will break the build on OpenBSD.
This was introduced in 2.4-dev10, no backport is needed.
The refactoring in commit 131b07be3 ("MEDIUM: server: Refactor
apply_server_state() to make it more readable") made the global
server_state_base be dereferenced before being checked, resulting
in a crash on certain files.
This happened in 2.4-dev10, no backport is needed.
When a "tcp-check" or a "http-check" rule is parsed, we try to get the
previous rule in the ruleset to get its index. We must take care to reset
the pointer on this rule in case an error is triggered later on the
parsing. Otherwise, the same rule may be released twice. For instance, it
happens with such line :
http-check meth GET uri / ## note there is no "send" parameter
This patch must be backported as far as 2.2.
If an agent-check is configured for a server, When the response is parsed,
the .health threshold of the agent must be updated on up/down/stopped/fail
command and not the threshold of the health-check. Otherwise, the
agent-check will compete with the health-check and may mark a DOWN server as
UP.
This patch should fix the issue #1176. It must be backported as far as 2.2.
CF_FL_ANALYZE flag is used to know a channel is filtered. It is important to
synchronize request and response channels when the filtering ends.
However, it is possible to call all request analyzers before starting the
filtering on the response channel. This means flt_end_analyze() may be
called for the request channel before flt_start_analyze() on the response
channel. Thus because CF_FL_ANALYZE flag is not set on the response channel,
we consider the filtering is finished on both sides. The consequence is that
flt_end_analyze() is not called for the response and backend filters are
unregistered before their execution on the response channel.
It is possible to encounter this bug on TCP frontend or CONNECT request on
HTTP frontend if the client shutdown is reveiced with the first read.
To fix this bug, CF_FL_ANALYZE is set when filters are attached to the
stream. It means, on the request channel when the stream is created, in
flt_stream_start(). And on both channels when the backend is set, in
flt_set_stream_backend().
This patch must be backported as far as 1.7.
Setting multiple http-request track-scX rules generates entries
which never expires.
If there was already an entry registered by a previous http rule
'stream_track_stkctr(&s->stkctr[rule->action], t, ts)' didn't
register the new 'ts' into the stkctr. And function is left
with no reference on 'ts' whereas refcount had been increased
by the '_get_entry'
The patch applies the same policy as the one showed on tcp track
rules and if there is successive rules the track counter keep the
first entry registered in the counter and nothing more is computed.
After validation this should be backported in all versions.
The recent default runqueue size reduction appeared to have significantly
lowered performance on low-thread count configs. Testing various values
runqueue values on different workloads under thread counts ranging from
1 to 64, it appeared that lower values are more optimal for high thread
counts and conversely. It could even be drawn that the optimal value for
various workloads sits around 280/sqrt(nbthread), and probably has to do
with both the L3 cache usage and how to optimally interlace the threads'
activity to minimize contention. This is much easier to optimally
configure, so let's do this by default now.
Instead of setting a hard-limit on runqueue-depth and keeping it short
to maintain fairness, let's allow the scheduler to automatically cut
the existing one in two equal halves if its size is between the configured
size and its double. This will allow to increase the default value while
keeping a low latency.
Emeric found that SSL+keepalive traffic had dropped quite a bit in the
recent changes, which could be bisected to recent commit 9205ab31d
("MINOR: ssl: mark the SSL handshake tasklet as heavy"). Indeed, a
first incarnation of this commit made use of the TASK_SELF_WAKING
flag but the last version directly used TASK_HEAVY, but it would still
continue to remove the already absent TASK_SELF_WAKING one instead of
TASK_HEAVY. As such, the SSL traffic remained processed with low
granularity.
No backport is needed as this is only 2.4.
The tests were made on slz and the zlib parsers for memlevel and windowsize
managed to escape the change made by commit 018251667 ("CLEANUP: config: make
the cfg_keyword parsers take a const for the defproxy"). This is now fixed.
These are some leftovers from the ancient code where they were still
called sessions, but these areas in the code remain confusing due to
this naming. They were now called "strm" which will not even affect
indenting nor alignment.
When implementing a client applet, a NULL dereference was encountered on
the error path which increment the counters.
Indeed, the counters incremented are the one in the listener which does
not exist in the case of client applets, so in sess->listener->counters,
listener is NULL.
This patch fixes the access to the listener structure when accessing
from a sesssion, most of the access are the counters in error paths.
Must be backported as far as 1.8.
The default proxy was passed as a variable to all parsers instead of a
const, which is not without risk, especially when some timeout parsers used
to make some int pointers point to the default values for comparisons. We
want to be certain that none of these parsers will modify the defaults
sections by accident, so it's important to mark this proxy as const.
This patch touches all occurrences found (89).
grq_total was incremented when picking tasks from the global run queue,
but this variable was not defined with threads disabled, and the code
was optimized away at -O2. No backport is needed.
This commit is a fix/complement to the following one :
08d87b3f49
BUG/MEDIUM: backend: never reuse a connection for tcp mode
It fixes the check for the early insertion of backend connections in
the reuse lists if the backend mode is HTTP.
The impact of this bug seems limited because :
- in tcp mode, no insertion is done in the avail list as mux_pt does not
support multiple streams.
- in http mode, muxes are also responsible to insert backend connections
in lists in their detach functions. Prior to this fix the reuse rate
could be slightly inferior.
It can be backported to 2.3.
Currently, there seems to be no way to have the transport layer ready
but not the mux in the function connect_server. Add a BUG_ON to report
if this implicit condition is not true anymore.
This should fix coverity report from github issue #1120.
The actconns list creates massive contention on low server counts because
it's in fact a list of streams using a server, all threads compete on the
list's head and it's still possible to see some watchdog panics on 48
threads under extreme contention with 47 threads trying to add and one
thread trying to delete.
Moving this list per thread is trivial because it's only used by
srv_shutdown_streams(), which simply required to iterate over the list.
The field was renamed to "streams" as it's really a list of streams
rather than a list of connections.
There are multiple per-thread lists in the listeners, which isn't the
most efficient in terms of cache, and doesn't easily allow to store all
the per-thread stuff.
Now we introduce an srv_per_thread structure which the servers will have an
array of, and place the idle/safe/avail conns tree heads into. Overall this
was a fairly mechanical change, and the array is now always initialized for
all servers since we'll put more stuff there. It's worth noting that the Lua
code still has to deal with its own deinit by itself despite being in a
global list, because its server is not dynamically allocated.
Till now servers were only initialized as part of the proxy setup loop,
which doesn't cover peers, tcp log, dns, lua etc. Let's move this part
out of this loop and instead iterate over all registered servers. This
way we're certain to visit them all.
The patch looks big but it's just a move of a large block with the
corresponding reindent (as can be checked with diff -b). It relies
on the two previous ones ("MINOR: server: add a global list of all
known servers and" and "CLEANUP: lua: set a dummy file name and line
number on the dummy servers").
It's a real pain not to have access to the list of all registered servers,
because whenever there is a need to late adjust their configuration, only
those attached to regular proxies are seen, but not the peers, lua, logs
nor DNS.
What this patch does is that new_server() will automatically add the newly
created server to a global list, and it does so as well for the 1 or 2
statically allocated servers created for Lua. This way it will be possible
to iterate over all of them.
The "socket_tcp" and "socket_ssl" servers had no config file name nor
line number, but this is sometimes annoying during debugging or later
in error messages, while all other places using new_server() or
parse_server() make sure to have a valid file:line set. Let's set
something to address this.
Currently the SSL layer checks the validity of its tasklet's context just
in case it would have been stolen, had the connection been idle. Now it
will be able to be notified by the mux when this situation happens so as
not to have to grab the idle connection lock on each pass. This reuses the
TASK_F_USR1 flag just as the muxes do.
These functions are used on the mux layer to indicate that the connection
is becoming idle and that the xprt ought to be careful before checking the
context or that it's not idle anymore and that the context is safe. The
purpose is to allow a mux which is going to release a connection to tell
the xprt to be careful when touching it. At the moment, the xprt are
always careful and that's costly so we want to have the ability to relax
this a bit.
No xprt layer uses this yet.
The muxes are touching the idle_conns_lock all the time now because
they need to be careful that no other thread has stolen their tasklet's
context.
This patch changes this a little bit by setting the TASK_F_USR1 flag on
the tasklet before marking a connection idle, and removing it once it's
not idle anymore. Thanks to this we have the guarantee that a tasklet
without this flag cannot be present in an idle list and does not need
to go through this costly lock. This is especially true for front
connections.
This flag will be usable by any application. It will be preserved across
wakeups so the application can use it to do various stuff. Some I/O
handlers will soon benefit from this.
It's been too short for quite a while now and is now full. It's still
time to extend it to 32-bits since we have room for this without
wasting any space, so we now gained 16 new bits for future flags.
The values were not reassigned just in case there would be a few
hidden u16 or short somewhere in which these flags are placed (as
it used to be the case with stream->pending_events).
The patch is tagged MEDIUM because this required to update the task's
process() prototype to use an int instead of a short, that's quite a
bunch of places.
It's cleaner to use a flag from the task's state to detect a tasklet
and it's even cheaper. One of the best benefits is that this will
allow to get the nice field out of the common part since the tasklet
doesn't need it anymore. This commit uses the last task bit available
but that's temporary as the purpose of the change is to extend this.
The PRNG used by the "random" LB algorithm was the central one which tries
hard to produce "correct" (i.e. hardly predictable) values suitable for use
in UUIDs or cookies. It's much too expensive for pure load balancing where
a cheaper thread-local PRNG is sufficient, and the current PRNG is part of
the hot places when running with many threads.
Let's switch to the stastistical PRNG instead, it's thread-local, very
fast, and with a period of (2^32)-1 which is more than enough to decide
on a server.
We frequently need to access a simple and fast PRNG for statistical
purposes. The debug_prng() function did exactly this using a xorshift
generator but its use was limited to debug only. Let's move this to
tools.h and tools.c to make it accessible everywhere. Since it needs to
be fast, its state is thread-local. An initialization function starts a
different initial value for each thread for better distribution.
In conn_backend_get() we can cause some extreme contention due to the
idle_conns_lock. Indeed, even though it's per-thread, it still causes
high contention when running with many threads. The reason is that all
threads which do not have any idle connections are quickly skipped,
till the point where there are still some, so the first reaching that
point will grab the lock and the other ones wait behind. From this
point, all threads are synchronized waiting on the same lock, and
will follow the leader in small jumps, all hindering each other.
Here instead of doing this we're using a trylock. This way when a thread
is already checking a list, other ones will continue to next thread. In
the worst case, a high contention will lead to a few new connections to
be set up, but this may actually be what is required to avoid contention
in the first place. With this change, the contention has mostly
disappeared on this lock (it's still present in muxes and transport
layers due to the takeover).
Surprisingly, checking for emptiness of the tree root before taking
the lock didn't address any contention.
A few improvements are still possible and desirable here. The first
one would be to avoid seeing all threads jump to the next one. We
could have each thread use a different prime number as the increment
so as to spread them across the entire table instead of keeping them
synchronized. The second one is that the lock in the muck layers
shouldn't be needed to check for the tasklet's context availability.
Using abort() occasionally results in unexploitable core due to issues
rewinding the stack. Let's use ABORT_NOW() which in addition to crashing
much closer to the call point also has the benefit of showing the call
trace.
We've reached a point where the global pools represent a significant
bottleneck with threads. On a 64-core machine, the performance was
divided by 8 between 32 and 64 H2 connections only because there were
not enough entries in the local caches to avoid picking from the global
pools, and the contention on the list there was very high. It becomes
obvious that we need to have an array of lists, but that will require
more changes.
In parallel, standard memory allocators have improved, with tcmalloc
and jemalloc finding their ways through mainstream systems, and glibc
having upgraded to a thread-aware ptmalloc variant, keeping this level
of contention here isn't justified anymore when we have both the local
per-thread pool caches and a fast process-wide allocator.
For these reasons, this patch introduces a new compile time setting
CONFIG_HAP_NO_GLOBAL_POOLS which is set by default when threads are
enabled with thread local pool caches, and we know we have a fast
thread-aware memory allocator (currently set for glibc>=2.26). In this
case we entirely bypass the global pool and directly use the standard
memory allocator when missing objects from the local pools. It is also
possible to force it at compile time when a good allocator is used with
another setup.
It is still possible to re-enable the global pools using
CONFIG_HAP_GLOBAL_POOLS, if a corner case is discovered regarding the
operating system's default allocator, or when building with a recent
libc but a different allocator which provides other benefits but does
not scale well with threads.
Errors reported by ssl_sock_dump_errors() to stderr would only report the
16 lower bits of the file descriptor because it used to be casted to ushort.
This can be backported to all versions but has really no importance in
practice since this is never seen.
Refactoring performed with the following Coccinelle patch:
@@
char *s;
@@
(
- ist2(s, strlen(s))
+ ist(s)
|
- ist2(strdup(s), strlen(s))
+ ist(strdup(s))
)
Note that this replacement is safe even in the strdup() case, because `ist()`
will not call `strlen()` on a `NULL` pointer. Instead is inserts a length of
`0`, effectively resulting in `IST_NULL`.
When dns_connect_nameserver() is called, the nameserver has always a dgram
field properly defined. The caller, dns_send_nameserver(), already performed
the appropriate verification.
When a DNS session is created, the call to ring_attach() never fails. The
ring is freshly initialized and there is other watcher on it. Thus, the call
always succeeds.
Instead of catching an error that must never happen, we use the DISGUISE()
macro to make static analyzers happy.
Recent changes on the server-state file loading have introduced a
regression. HAproxy crashes if a backend with no server-state file is
disabled in the configuration. Indeed, configuration of such backends is not
finalized. Thus many fields are not defined.
To fix the bug, disabled backends must be ignored. In addition a BUG_ON()
has been added to verify the proxy mode regarding the server-state file. It
must be specified (none, global or local) for enabled backends.
No backport needed.
hlua_pushstrippedstring() function strips leading and trailing LWS
characters. But the result length it too short by 1 byte. Thus the last
non-LWS character is stripped. Note that a string containing only LWS
characters resulting to a stipped string with an invalid length (-1). This
leads to a lua runtime error.
This bug was reported in the issue #1155. It must be backported as far as
1.7.
If dispatch mode or transparent backend is used, the backend connection
target is a proxy instead of a server. In these cases, the reuse of
backend connections is not consistent.
With the default behavior, no reuse is done and every new request uses a
new connection. However, if http-reuse is set to never, the connection
are stored by the mux in the session and can be reused for future
requests in the same session.
As no server is used for these connections, no reuse can be made outside
of the session, similarly to http-reuse never mode. A different
http-reuse config value should not have an impact. To achieve this, mark
these connections as private to have a defined behavior.
For this feature to properly work, the connection hash has been slightly
adjusted. The server pointer as an input as been replaced by a generic
target pointer to refer to the server or proxy instance. The hash is
always calculated on connect_server even if the connection target is not
a server. This also requires to allocate the connection hash node for
every backend connections, not just the one with a server target.
Fix a leak in connect_server which happens when a connection is reused
and a bind_addr was allocated because transparent mode is active. The
connection has already an allocated bind_addr so free the newly
allocated one.
No backport needed.
That comma should've been a semicolon. Fortunately, as it is now there
is no impact thanks to operators precedence, and all expressions are
properly evaluated. But this is troubling and the risk is high to
turn it into an effective bug with a minor change.
Introduced in b8ce8905cf which first
appeared in 2.1-dev3. This fix must be backported to 2.1+.
Since this commit:
144289b45 ("REORG: move init_default_instance() to proxy.c and pass it the defproxy pointer")
as quic_transport_params_init() has been moved from cfgparse.c to proxy.c this
latter source file must include xprt_quic.h header.
Should fix#1153 issue.
When the processing stage is finished for a SPOE applet, before returning it
into the idle list, we check if the assigned server appears as full or if
there are some pending connections on the backend or the assigned server. If
yes, it means we reach a maxconn and we close the applet to free a
slot. Otherwise, the applet can be reused. This test is only performed if
there are more than one thread.
It is important to close SPOE applets when there are pending connections for
multithreaded instances because connections with the SPOE agents are
persistent and local to a thread (applets are local to a thread). If a
maxconn is configured, some threads may take all available slots for a
while, leaving remaining threads without any free slot to process SPOE
messages. It is especially true if the maxconn is low.
This patch should fix the issue #705. It must be backported as far as
1.8. However, the code in 1.8 is quite different, a test must be performed
to be sure it works well.
When the selected server has no address, the destination address of the
client is used. However, for now, only the address is set, not the
family. Thus depending on how the server is configured and the client's
destination address, the server address family may be wrong.
For instance, with such server :
server srv 0.0.0.0:0
The server address family is AF_INET. The server connection will fail if a
client is asking for an IPv6 destination.
To fix the bug, we take care to set the rigth family, the family of the
client destination address.
This patch should fix the issue #202. It must be backported to all stable
versions.
If an IPv4 is set via a TCP/HTTP set-dst rule, the original port must be
preserved or set to 0 if the previous family was neither AF_INET nor
AF_INET6. The first case is not an issue because the port remains the
same. But if the previous family was, for instance, AF_UNIX, the port is not
set to 0 and have an undefined value.
This patch must be backported as far as 1.7.
There was a free(ptr) followed by ptr=malloc(ptr, len), which is the
equivalent of ptr = realloc(ptr, len) but slower and less clean. Let's
replace this.
In ssl_sock_free_srv_ctx() there are some calls to free() which are not
followed by a zeroing of the pointers. For now this function is only used
during deinit but it could be used at run time in the near future, so
better secure this.
In sample_store(), depending on the new sample types, the area pointer
was not always zeroed after being freed. Let's make sure it's always the
case to avoid the risk of dangling pointers being misused.
A few occurrences of calls to free() to free a section name,
peers name or server name were using casts and didn't include
the trailing free, let's switch them to ha_free().
This makes the code more readable and less prone to copy-paste errors.
In addition, it allows to place some __builtin_constant_p() predicates
to trigger a link-time error in case the compiler knows that the freed
area is constant. It will also produce compile-time error if trying to
free something that is not a regular pointer (e.g. a function).
The DEBUG_MEM_STATS macro now also defines an instance for ha_free()
so that all these calls can be checked.
178 occurrences were converted. The vast majority of them were handled
by the following Coccinelle script, some slightly refined to better deal
with "&*x" or with long lines:
@ rule @
expression E;
@@
- free(E);
- E = NULL;
+ ha_free(&E);
It was verified that the resulting code is the same, more or less a
handful of cases where the compiler optimized slightly differently
the temporary variable that holds the copy of the pointer.
A non-negligible amount of {free(str);str=NULL;str_len=0;} are still
present in the config part (mostly header names in proxies). These
ones should also be cleaned for the same reasons, and probably be
turned into ist strings.
A network may be specified to avoid header addition for "forwardfor" and
"orignialto" option via the "except" parameter. However, only IPv4
networks/addresses are supported. This patch adds the support of IPv6.
To do so, the net_addr structure is used to store the parameter value in the
proxy structure. And ipcmp2net() function is used to perform the comparison.
This patch should fix the issue #1145. It depends on the following commit:
* c6ce0ab MINOR: tools: Add function to compare an address to a network address
* 5587287 MINOR: tools: Add net_addr structure describing a network addess
ipcmp2net() function may be used to compare an addres (struct
sockaddr_storage) to a network address (struct net_addr). Among other
things, this function will be used to add support of IPv6 for "except"
parameter of "forwardfor" and "originalto" options.
When an except parameter is used for originalto option, only the destination
address must be evaluated. Especially, the address family of the destination
must be tested and not the source one.
This patch must be backported to all stable versions. However be careful,
depending the versions the code may be slightly different.
The preliminary approach to dealing with heavy tasks forced us to quit
the poller after meeting one. Now instead we process at most one per poll
loop and ignore the next ones, so that we get more bandwidth to process
all other classes.
Doing so further reduced the induced HTTP request latency at 100k req/s
under the stress of 1000 concurrent SSL handshakes in the following
proportions:
| default | low-latency
---------+------------+--------------
before | 2.75 ms | 2.0 ms
after | 1.38 ms | 0.98 ms
In both cases, the latency is roughly halved. It's worth noting that
both values are now exactly 10 times better than in 2.4-dev9. Even the
percentiles have much improved. For 16 HTTP connections (1 per thread)
competing with 1000 SSL handshakes, we're seeing these long-tail
latencies (in milliseconds) :
| 99.5% | 99.9% | 100%
-----------+---------+---------+--------
2.4-dev9 | 48.4 | 58.1 | 78.5
previous | 6.2 | 11.4 | 67.8
this patch | 2.8 | 2.9 | 6.1
The task latency profiling report now shows this in default mode:
$ socat - /tmp/sock1 <<< "show profiling"
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 3061966 2.224s 726.0ns 42.03s 13.72us
h1_io_cb 3061960 6.418s 2.096us 18.76m 367.6us
process_stream 3059982 9.137s 2.985us 15.52m 304.3us
ssl_sock_io_cb 602657 4.265m 424.7us 4.736h 28.29ms
h1_timeout_task 202973 - - 6.254s 30.81us
accept_queue_process 135547 1.179s 8.699us 16.29s 120.1us
srv_cleanup_toremove_conns 81 15.64ms 193.1us 30.87ms 381.1us
task_run_applet 10 758.7us 75.87us 51.77us 5.176us
srv_cleanup_idle_conns 4 375.3us 93.83us 54.52us 13.63us
And this in low-latency mode, showing that both si_cs_io_cb() and process_stream()
have significantly benefitted from the improvement, with values 50 to 200 times
smaller than 2.4-dev9:
$ socat - /tmp/sock1 <<< "show profiling"
Per-task CPU profiling : on # set profiling tasks {on|auto|off}
Tasks activity:
function calls cpu_tot cpu_avg lat_tot lat_avg
h1_io_cb 6407006 11.86s 1.851us 31.14m 291.6us
process_stream 6403890 18.40s 2.873us 2.134m 20.00us
si_cs_io_cb 6403866 4.139s 646.0ns 1.773m 16.61us
ssl_sock_io_cb 894326 6.407m 429.9us 7.326h 29.49ms
h1_timeout_task 301189 - - 8.440s 28.02us
accept_queue_process 211989 1.691s 7.977us 21.48s 101.3us
srv_cleanup_toremove_conns 220 23.46ms 106.7us 65.61ms 298.2us
task_run_applet 16 1.219ms 76.17us 181.7us 11.36us
srv_cleanup_idle_conns 12 713.3us 59.44us 168.4us 14.03us
The changes are slightly more invasive than previous ones and depend on
recent patches so they are not likely well suited for backporting.
Instead of placing heavy tasklets into the TL_BULK queue, we now place
them into the TL_HEAVY one, which is assigned a default weight of ~1%
load at once. This way heavy tasks will not block TL_BULK anymore.
This class will be used exclusively for heavy processing tasklets. It
will be cleaner than mixing them with the bulk ones. For now it's
allocated ~1% of the CPU bandwidth.
The largest part of the patch consists in re-arranging the fields in the
task_per_thread structure to preserve a clean alignment with one more
list head. Since we're now forced to increase the struct past a second
cache line, it now uses 4 cache lines (for easy multiplying) with the
first two ones being exclusively used by local operations and the third
one mostly by atomic operations. Interestingly, this better arrangement
causes less stress and reduced the response time by 8 microseconds at
1 million requests per second.
A potential null pointer dereference was reported with an old gcc
version (6.5)
src/ssl_ckch.c: In function 'cli_parse_set_cert':
src/ssl_ckch.c:844:7: error: potential null pointer dereference [-Werror=null-dereference]
if (!ssl_sock_copy_cert_key_and_chain(src->ckch, dst->ckch))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ssl_ckch.c:844:7: error: potential null pointer dereference [-Werror=null-dereference]
src/ssl_ckch.c: In function 'ckchs_dup':
src/ssl_ckch.c:844:7: error: potential null pointer dereference [-Werror=null-dereference]
if (!ssl_sock_copy_cert_key_and_chain(src->ckch, dst->ckch))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ssl_ckch.c:844:7: error: potential null pointer dereference [-Werror=null-dereference]
This could happen if ckch_store_new() fails to allocate memory and returns NULL.
This patch must be backported with 8f71298 since it was wrongly fixed and
the bug could happen.
Must be backported as far as 2.2.
These function names are unbearably long, they don't even fit into the
screen in "show profiling", let's trim the "_connections" to "_conns",
which happens to match the name of the lists there.
There's a fairness issue between SSL and clear text. A full end-to-end
cleartext connection can require up to ~7.7 wakeups on average, plus 3.3
for the SSL tasklet, one of which is particularly expensive. So if we
accept to process many handshakes taking 1ms each, we significantly
increase the processing time of regular tasks just by adding an extra
delay between their calls. Ideally in order to be fair we should have a
1:18 call ratio, but this requires a bit more accounting. With very little
effort we can mark the SSL handshake tasklet as TASK_HEAVY until the
handshake completes, and remove it once done.
Doing so reduces from 14 to 3.0 ms the total response time experienced
by HTTP clients running in parallel to 1000 SSL clients doing full
handshakes in loops. Better, when tune.sched.low-latency is set to "on",
the latency further drops to 1.8 ms.
The tasks latency distribution explain pretty well what is happening:
Without the patch:
$ socat - /tmp/sock1 <<< "show profiling"
Per-task CPU profiling : on # set profiling tasks {on|auto|off}
Tasks activity:
function calls cpu_tot cpu_avg lat_tot lat_avg
ssl_sock_io_cb 2785375 19.35m 416.9us 5.401h 6.980ms
h1_io_cb 1868949 9.853s 5.271us 4.829h 9.302ms
process_stream 1864066 7.582s 4.067us 2.058h 3.974ms
si_cs_io_cb 1733808 1.932s 1.114us 26.83m 928.5us
h1_timeout_task 935760 - - 1.033h 3.975ms
accept_queue_process 303606 4.627s 15.24us 16.65m 3.291ms
srv_cleanup_toremove_connections452 64.31ms 142.3us 2.447s 5.415ms
task_run_applet 47 5.149ms 109.6us 57.09ms 1.215ms
srv_cleanup_idle_connections 34 2.210ms 65.00us 87.49ms 2.573ms
With the patch:
$ socat - /tmp/sock1 <<< "show profiling"
Per-task CPU profiling : on # set profiling tasks {on|auto|off}
Tasks activity:
function calls cpu_tot cpu_avg lat_tot lat_avg
ssl_sock_io_cb 3000365 21.08m 421.6us 20.30h 24.36ms
h1_io_cb 2031932 9.278s 4.565us 46.70m 1.379ms
process_stream 2010682 7.391s 3.675us 22.83m 681.2us
si_cs_io_cb 1702070 1.571s 922.0ns 8.732m 307.8us
h1_timeout_task 1009594 - - 17.63m 1.048ms
accept_queue_process 339595 4.792s 14.11us 3.714m 656.2us
srv_cleanup_toremove_connections779 75.42ms 96.81us 438.3ms 562.6us
srv_cleanup_idle_connections 48 2.498ms 52.05us 178.1us 3.709us
task_run_applet 17 1.738ms 102.3us 11.29ms 663.9us
other 1 947.8us 947.8us 202.6us 202.6us
=> h1_io_cb() and process_stream() are divided by 6 while ssl_sock_io_cb() is
multipled by 4
And with low-latency on:
$ socat - /tmp/sock1 <<< "show profiling"
Per-task CPU profiling : on # set profiling tasks {on|auto|off}
Tasks activity:
function calls cpu_tot cpu_avg lat_tot lat_avg
ssl_sock_io_cb 3000565 20.96m 419.1us 20.74h 24.89ms
h1_io_cb 2019702 9.294s 4.601us 49.22m 1.462ms
process_stream 2009755 6.570s 3.269us 1.493m 44.57us
si_cs_io_cb 1997820 1.566s 783.0ns 2.985m 89.66us
h1_timeout_task 1009742 - - 1.647m 97.86us
accept_queue_process 494509 4.697s 9.498us 1.240m 150.4us
srv_cleanup_toremove_connections1120 92.32ms 82.43us 463.0ms 413.4us
srv_cleanup_idle_connections 70 2.703ms 38.61us 204.5us 2.921us
task_run_applet 13 1.303ms 100.3us 85.12us 6.548us
=> process_stream() is divided by 100 while ssl_sock_io_cb() is
multipled by 4
Interestingly, the total HTTPS response time doesn't increase and even very
slightly decreases, with an overall ~1% higher request rate. The net effect
here is a redistribution of the CPU resources between internal tasks, and
in the case of SSL, handshakes wait bit more but everything after completes
faster.
This was made simple enough to be backportable if it helps some users
suffering from high latencies in mixed traffic.
While the scheduler is priority-aware and class-aware, and consistently
tries to maintain fairness between all classes, it doesn't make use of a
fine execution budget to compensate for high-latency tasks such as TLS
handshakes. This can result in many subsequent calls adding multiple
milliseconds of latency between the various steps of other tasklets that
don't even depend on this.
An ideal solution would be to add a 4th queue, have all tasks announce
their estimated cost upfront and let the scheduler maintain an auto-
refilling budget to pick from the most suitable queue.
But it turns out that a very simplified version of this already provides
impressive gains with very tiny changes and could easily be backported.
The principle is to reserve a new task flag "TASK_HEAVY" that indicates
that a task is expected to take a lot of time without yielding (e.g. an
SSL handshake typically takes 700 microseconds of crypto computation).
When the scheduler sees this flag when queuing a tasklet, it will place
it into the bulk queue. And during dequeuing, we accept only one of
these in a full round. This means that the first one will be accepted,
will not prevent other lower priority tasks from running, but if a new
one arrives, then the queue stops here and goes back to the polling.
This will allow to collect more important updates for other tasks that
will be batched before the next call of a heavy task.
Preliminary tests consisting in placing this flag on the SSL handshake
tasklet show that response times under SSL stress fell from 14 ms
before the patch to 3.0 ms with the patch, and even 1.8 ms if
tune.sched.low-latency is set to "on".
Only the first 3 characters are compared for ';no-maint' suffix in
http_handle_stats. Fix it by doing a full match over the entire suffix.
As a side effect, the ';norefresh' suffix matched the inaccurate
comparison, so the maintenance servers were always hidden on the stats
page in this case.
no-maint suffix is present since commit
3e32036701
MINOR: stats: also support a "no-maint" show stat modifier
It should be backported up to 2.3.
This fixes github issue #1147.
In H1, H2 and FCGI muxes, in the show_fd function, there is duplicated test on
the stream's subs field.
This patch fixes the issue #1142. It may be backported as far as 2.2.
Some static functions are now exported and renamed to follow the same
pattern of other exported functions. Here is the list :
* update_server_fqdn: Renamed to srv_update_fqdn and exported
* update_server_check_addr_port: renamed to srv_update_check_addr_port and exported
* update_server_agent_addr_port: renamed to srv_update_agent_addr_port and exported
* update_server_addr: renamed to srv_update_addr
* update_server_addr_potr: renamed to srv_update_addr_port
* srv_prepare_for_resolution: exported
This change is mandatory to move all functions dealing with the server-state
files in a separate file.
This change is not huge but may have a visible impact for users. Now, if a
line of a server-state file is corrupted, the whole file is ignored. A
warning is emitted with the corrupted line number.
In fact, there is no way to recover from a corrupted line. A line is
considered as corrupted if it is too long (truncated line) or if it contains
the wrong number of arguments. In both cases, it means the file was forged
(or at least manually edited). It is safer to ignore it.
Note for now, memory allocation errors are not reported and the
corresponding line is silently ignored.
Now, srv_state_parse_and_store_line() function is used to parse and store a
line in a tree. It is used for global and local server-state files. This
significatly simplies the apply_server_state() function.
Just like for the global server-state file, the line of a local server-state
file are now stored in a tree. This way, the file is fully parsed before
loading the servers state. And with this change, global and local
server-state files are now handled the same way. This will be the
opportunity to factorize the code. It is also a good way to validate the
file before loading any server state.
The loop on the servers of a proxy to load the server states was moved in
the function srv_state_px_update(). This simplify a bit the
apply_server_state() function. It is aslo mandatory to simplify the loading
of local server-state file.
When a server for a given backend is found in the tree containing all lines
of the global server-state file, the node is removed from the tree. It is
useless to keep it longer. It is a small improvement, but it may also be
usefull to track the orphan lines (not used for now).
Parsed parameters are now stored in the tree of server-state lines. This
way, a line from the global server-state file is only parsed once. Before,
it was parsed a first time to store it in the tree and one more time to load
the server state. To do so, the server-state line object must be allocated
before parsing a line. This means its size must no longer depend on the
length of first parsed parameters (backend and server names). Thus the node
type was changed to use a hashed key instead of a string.
Now, we read a full line and expects to found an integer only on it. And if
the line is empty or truncated, an error is returned. If the version is not
valid, an error is also returned. This way, the first line is no longer
partially read.
There is no reason to use a global variable to store the lines of the global
server-state file. This tree is only used during the file parsing, as a line
cache. Now the eb-tree is declared as a local variable in the
apply_server_state() function.
The structure used to store a server-state line in an eb-tree has a too
generic name. Instead of state_line, the structure is renamed as
server_state_line.
<state_line.name_name> field is a node in an eb-tree. Thus, instead of
"name_name", we now use "node" to name this field. If is a more explicit
name and not too strange.
The apply_server_state() function is really hard to read. Thus it was
refactored to be more maintainable. First, an helper function is used to get
the server-state file path. Some useless variables were removed and most of
other variables were renamed to be more readable. The error messages are now
prefixed to know the context (global vs per-proxy). Finally, the loop on the
proxies list was simplified.
This patch may seem a bit huge, but the changes are not so important.
There is no reason to fill two parameter arrays in srv_state_parse_line()
function. Now, only one array is used. The 4th first entries are just
skipped when srv_update_state() is called.
The srv_state_parse_line() function was rewritten to be more strict. First
of all, it is possible to make the difference between an ignored line and an
malformed one. Then, only blank characters (spaces and tabs) are now allowed
as field separator. An error is reported for truncated lines or for lines
with an unexpected number of arguments regarding the provided version.
However, for now, errors are ignored by the caller, invalid lines are just
skipped.
First, we don't want to measure wakeup times if the call date had not
been set before profiling was enabled at run time. And second, we may
only collect the value before clearing the TASK_IN_LIST bit, otherwise
another wakeup might happen on another thread and replace the call date
we're about to use, hence artificially lower the wakeup times.
It is extremely useful to be able to observe the wakeup latency of some
important I/O operations, so let's accept to inflate the tasklet struct
by 8 extra bytes when DEBUG_TASK is set. With just this we have enough
to get live reports like this:
$ socat - /tmp/sock1 <<< "show profiling"
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 8099492 4.833s 596.0ns 8.974m 66.48us
h1_io_cb 7460365 11.55s 1.548us 2.477m 19.92us
process_stream 7383828 22.79s 3.086us 18.39m 149.5us
h1_timeout_task 4157 - - 348.4ms 83.81us
srv_cleanup_toremove_connections751 39.70ms 52.86us 10.54ms 14.04us
srv_cleanup_idle_connections 21 1.405ms 66.89us 30.82us 1.467us
task_run_applet 16 1.058ms 66.13us 446.2us 27.89us
accept_queue_process 7 34.53us 4.933us 333.1us 47.58us
Instead of decrementing grq_total once per task picked from the global
run queue, let's do it at once after the loop like we do for other
counters. This simplifies the code everywhere. It is not expected to
bring noticeable improvements however, since global tasks tend to be
less common nowadays.
Now we don't need to decrement rq_total when we pick a tack in the tree
to immediately increment it again after installing it into the local
list. Instead, we simply add to the local queue count the number of
globally picked tasks. Avoiding this shows ~0.5% performance gains at
1Mreq/s (2M task switches/s).
As indicated in previous commit, this function tries to guess which tree
the task is in to figure what counters to update, while we already have
that info in the caller. Let's just pick the relevant parts to place them
in the caller.
In process_runnable_tasks() we're still calling __task_unlink_rq() to
pick a task, and this function tries to guess where to pick the task
from and which counter to update while the caller's context already
has everything. Worse, the number of local tasks is decremented then
recredited, doubling the operations. In order to avoid this we first
need to keep separate counters for local and global tasks that were
picked. This is what this patch does.
The function htx_reserve_max_data() should be used to get an HTX DATA block
with the max possible size. A current block may be extended or a new one
created, depending on the HTX message state. But the idea is to let the
caller to copy a bunch of data without requesting many new blocks. It is its
responsibility to resize the block at the end, to set the final block size.
This function will be used to parse messages with small chunks. Indeed, we
can have more than 2700 1-byte chunks in a 16Kb of input data. So it is easy
to understand how this function may help to improve the parsing of chunk
messages.
If the DNS resolution failed for a server, its ip address must be
removed. Otherwise, the server is stopped but keeps its ip. This may be
confusing when the servers state are retrieved on the CLI and it may lead to
undefined behavior if HAproxy is configured to load its servers state from a
file.
This patch should be backported as far as 2.0.
When a SRV record expires, the ip/port assigned to the associated server are
now removed. Otherwise, the server is stopped but keeps its ip/port while
the server hostname is removed. It is confusing when the servers state are
retrieve on the CLI and may be a problem if saved in a server-state
file. Because the reload may fail because of this inconsistency.
Here is an example:
* Declare a server template in a backend, using the resolver <dns>
server-template test 2 _http._tcp.example.com resolvers dns check
* 2 SRV records are announced with the corresponding additional
records. Thus, 2 servers are filled. Here is the "show servers state"
output :
2 frt 1 test1 192.168.1.1 2 64 0 1 2 15 3 4 6 0 0 0 http1.example.com 8001 _http._tcp.example.com 0 0 - - 0
2 frt 2 test2 192.168.1.2 2 64 0 1 1 15 3 4 6 0 0 0 http2.example.com 8002 _http._tcp.example.com 0 0 - - 0
* Then, one additional record is removed (or a SRV record is removed, the
result is the same). Here is the new "show servers state" output :
2 frt 1 test1 192.168.1.1 2 64 0 1 38 15 3 4 6 0 0 0 http1.example.com 8001 _http._tcp.example.com 0 0 - - 0
2 frt 2 test2 192.168.1.2 0 96 0 1 19 15 3 0 14 0 0 0 - 8002 _http._tcp.example.com 0 0 - - 0
On reload, if a server-state file is used, this leads to undefined behaviors
depending on the configuration.
This patch should be backported as far as 2.0.
When a SRV record was created, it used to register the regular server name
resolution callbacks. That said, SRV records and regular server name
resolution don't work the same way, furthermore on error management.
This patch introduces a new call back to manage DNS errors related to
the SRV queries.
this fixes github issue #50.
Backport status: 2.3, 2.2, 2.1, 2.0
If no additional record is associated to a SRV record, its TTL must not be
renewed. Otherwise the entry never expires. Thus once announced a first
time, the entry remains blocked on the same IP/port except if a new announce
replaces the old one.
Now, the TTL is updated if a SRV record is received while a matching
existing one is found with an additional record or when an new additional
record is assigned to an existing SRV record.
This patch should be backported as far as 2.2.
At the end of resolv_validate_dns_response(), if a received additionnal
record is not assigned to an existing server record, it is released. But the
condition to do so is buggy. If "answer_record" (the received AR) is not
assigned, "tmp_record" is not a valid record object. It is just a dummy
record "representing" the head of the record list.
Now, the condition is far cleaner. This patch must be backported as far as
2.2.
This function has become large with the multi-queue scheduler. We need
to keep the fast path and the debugging parts inlined, but the rest now
moves to task.c just like was done for task_wakeup(). This has reduced
the code size by 6kB due to less inlining of large parts that are always
context-dependent, and as a side effect, has increased the overall
performance by 1%.
The nb_tasks counter was still global and gets incremented and decremented
for each task_new()/task_free(), and was read in process_runnable_tasks().
But it's only used for stats reporting, so doing this this often is
pointless and expensive. Let's move it to the task_per_thread struct and
have the stats sum it when needed.
The test in __task_wakeup() to figure if the remote threads are sleeping
doesn't make sense outside of the global runqueue test, since there are
only two possibilities here: local runqueue or global runqueue, hence a
sleeping thread is another one and can only happen when sending to the
global run queue. Let's move the test inside the "if" block.
Historically we used to call __task_wakeup() with a known tree root but
this is not the case and the code has remained needlessly complicated
with the root calculation in task_wakeup() passed in argument to
__task_wakeup() which compares it again.
Let's get rid of this and just move the detection code there. This
eliminates some ifdefs and allows to simplify the test conditions quite
a bit.
This one is systematically misunderstood due to its unclear name. It
is in fact the number of tasks in the local tasklet list. Let's call
it "tasks_in_list" to remove some of the confusion.
This one is exclusively used as a boolean nowadays and is non-zero only
when the thread-local run queue is not empty. Better check the root tree's
pointer and avoid updating this counter all the time.
This counter is solely used for reporting in the stats and is the hottest
thread contention point to date. Moving it to the scheduler and having a
separate one for the global run queue dramatically improves the performance,
showing a 12% boost on the request rate on 16 threads!
In addition, the thread debugging output which used to rely on rqueue_size
was not totally accurate as it would only report task counts. Now we can
return the exact thread's run queue length.
It is also interesting to note that there are still a few other task/tasklet
counters in the scheduler that are not efficiently updated because some cover
a single area and others cover multiple areas. It looks like having a distinct
counter for each of the following entries would help and would keep the code
a bit cleaner:
- global run queue (tree)
- per-thread run queue (tree)
- per-thread shared tasklets list
- per-thread local lists
Maybe even splitting the shared tasklets lists between pure tasklets and
tasks instead of having the whole and tasks would simplify the code because
there remain a number of places where several counters have to be updated.
dns_session_release() only uses its struct dns_stream_server to access
the lock, so a warning is emitted when threads are disabled. Let's mark
it __maybe_unused.
The lock was still used exclusively to deal with the concurrency between
the "show sess" release handler and a stream_new() or stream_free() on
another thread. All other accesses made by "show sess" are already done
under thread isolation. The release handler only requires to unlink its
node when stopping in the middle of a dump (error, timeout etc). Let's
just isolate the thread to deal with this case so that it's compatible
with the dump conditions, and remove all remaining locking on the streams.
This effectively kills the streams lock. The measured gain here is around
1.6% with 4 threads (374krps -> 380k).
The global streams list is exclusively used for "show sess", to look up
a stream to shut down, and for the hard-stop. Having all of them in a
single list is extremely expensive in terms of locking when using threads,
with performance losses as high as 7% having been observed just due to
this.
This patch makes the list per-thread, since there's no need to have a
global one in this situation. All call places just iterate over all
threads. The most "invasive" changes was in "show sess" where the end
of list needs to go back to the beginning of next thread's list until
the last thread is seen. For now the lock was maintained to keep the
code auditable but a next commit should get rid of it.
The observed performance gain here with only 4 threads is already 7%
(350krps -> 374krps).
Instead of placing the current stream at the end of the stream list when
issuing a "show sess" on the CLI as was done in 2.2 with commit c6e7a1b8e
("MINOR: cli: make "show sess" stop at the last known session"), now we
compare the listed stream's epoch with the dumping stream's and stop on
more recent ones.
This way we're certain to always only dump known streams at the moment we
issue the dump command without having to modify the list. In theory we
could miss some streams if more than 2^31 "show sess" requests are issued
while an old stream remains present, but that's 68 years at 1 "show sess"
per second and it's unlikely we'll keep a process, let alone a stream, that
long.
It could be verified that the count of dumped streams still matches the
one before this change.
The "show sess" CLI command currently lists all streams and needs to
stop at a given position to avoid dumping forever. Since 2.2 with
commit c6e7a1b8e ("MINOR: cli: make "show sess" stop at the last known
session"), a hack consists in unlinking the stream running the applet
and linking it again at the current end of the list, in order to serve
as a delimiter. But this forces the stream list to be global, which
affects scalability.
This patch introduces an epoch, which is a global 32-bit counter that
is incremented by the "show sess" command, and which is copied by newly
created streams. This way any stream can know whether any other one is
newer or older than itself.
For now it's only stored and not exploited.
The hard-stop event didn't wake threads up. In the past it wasn't an issue
as the poll timeout was limited to 1 second, but since commit 4f59d3861
("MINOR: time: increase the minimum wakeup interval to 60s") it has become
a problem because old processes can remain live for up to one minute after
the hard-stop-after delay. Let's just wake them up.
This may be backported to older releases, though before 2.4 the extra
delay was only one second.
There's no locking around the lookup of a stream nor its shutdown
when issuing "shutdown sessions" over the CLI so the risk of crashing
the process is particularly high.
Let's use a thread_isolate() there which is suitable for this task, and
there are not that many alternatives.
This must be backported to 1.8.
When setting hard-stop-after, hard_stop() is called at the end to kill
last pending streams. Unfortunately there's no locking there while
walking over the streams list nor when shutting them down, so it's
very likely that some old processes have been crashing or gone wild
due to this. Let's use a thread_isolate() call for this as we don't
have much other choice (and it happens once in the process' life,
that's OK).
This must be backported to 1.8.
This patch adds a lock to functions vars_get_by_name() and
vars_get_by_desc() to protect accesses to the list of variables.
After the variable is fetched, a sample data is duplicated by using
smp_dup() because the variable may be modified by another thread.
This should be backported to all versions supporting vars along with
"BUG/MINOR: sample: secure convs that accept base64 string and var name
as args" which this patch depends on.
This patch adds a few improvements in order to secure the use of
converters that accept base64 string and variable name as arguments.
The first change is within related function sample_conv_var2smp_str()
which now flags the sample as SMP_F_CONST if the argument is of type
ARGT_STR. This makes the sample more safe for later use.
A new function sample_check_arg_base64() is added. It checks an argument
and fills it with a variable type if the argument string contains a
valid variable name. If failed, it tries to perform a base64 decode
operation on a non-empty string, and fills the argument with the decoded
content which can be used later, without any additional base64dec()
function calls during runtime. This means that haproxy configuration
check may fail if variable lookup fails and an invalid base64 encoded
string is specified as an argument for such converters.
Both converters, "aes_gcm_dec" and "hmac", now use alloc_trash_chunk()
in order to allocate additional buffers for various conversions, and
avoid the use of a pre-allocated trash chunks directly (usually returned
by get_trash_chunk()). The function sample_check_arg_base64() is used
for both converters in order to check their arguments specified within
the haproxy configuration.
This patch should be backported as far as 2.0. However, it is important
to keep in mind a few things. The "hmac" converter is only available
starting with 2.2. In versions prior to 2.2, the "aes_gcm_dec" converter
and sample_conv_var2smp_str() are implemented in src/ssl_sock.c. Thus
the patch will have to be adapted on these versions.
Note that this patch is required for a subsequent, more important fix.
A potential null pointer dereference was reported with an old gcc
version (6.5)
src/ssl_ckch.c: In function 'cli_parse_set_cert':
src/ssl_ckch.c:838:7: error: potential null pointer dereference [-Werror=null-dereference]
if (!ssl_sock_copy_cert_key_and_chain(src->ckch, dst->ckch))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ssl_ckch.c:838:7: error: potential null pointer dereference [-Werror=null-dereference]
src/ssl_ckch.c: In function 'ckchs_dup':
src/ssl_ckch.c:838:7: error: potential null pointer dereference [-Werror=null-dereference]
if (!ssl_sock_copy_cert_key_and_chain(src->ckch, dst->ckch))
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/ssl_ckch.c:838:7: error: potential null pointer dereference [-Werror=null-dereference]
cc1: all warnings being treated as errors
This case does not actually happen but it's better to fix the ckch API
with a NULL check.
Could be backported as far as 2.1.
RAND_keep_random_devices_open is OpenSSL specific function, not
implemented in LibreSSL and BoringSSL. Let us define guard
HAVE_SSL_RAND_KEEP_RANDOM_DEVICES_OPEN in include/haproxy/openssl-compat.h
That guard does not depend anymore on HA_OPENSSL_VERSION
The runqueue_ticks counts the number of task wakeups and is used to
position new tasks in the run queue, but since we've had per-thread
run queues, the values there are not very relevant anymore and the
nice value doesn't apply well if some threads are more loaded than
others. In addition, letting all threads compete over a shared counter
is not smart as this may cause some excessive contention.
Let's move this index close to the run queues themselves, i.e. one per
thread and a global one. In addition to improving fairness, this has
increased global performance by 2% on 16 threads thanks to the lower
contention on rqueue_ticks.
Fairness issues were not observed, but if any were to be, this patch
could be backported as far as 2.0 to address them.
Historically this function would try to wake the most accurate number of
process_stream() waiters. But since the introduction of filters which could
also require buffers (e.g. for compression), things started not to be as
accurate anymore. Nowadays muxes and transport layers also use buffers, so
the runqueue size has nothing to do anymore with the number of supposed
users to come.
In addition to this, the threshold was compared to the number of free buffer
calculated as allocated minus used, but this didn't work anymore with local
pools since these counts are not updated upon alloc/free!
Let's clean this up and pass the number of released buffers instead, and
consider that each waiter successfully called counts as one buffer. This
is not rocket science and will not suddenly fix everything, but at least
it cannot be as wrong as it is today.
This could have been marked as a bug given that the current situation is
totally broken regarding this, but this probably doesn't completely fix
it, it only goes in a better direction. It is possible however that it
makes sense in the future to backport this as part of a larger series if
the situation significantly improves.
The buffer wait queue used to be global historically but this doest not
make any sense anymore given that the most common use case is to have
thread-local pools. Thus there's no point waking up waiters of other
threads after releasing an entry, as they won't benefit from it.
Let's move the queue head to the thread_info structure and use
ti->buffer_wq from now on.
When a server-state line is parsed, a test is performed to be sure there is
enough but not too much fields. However the test is buggy. The bug was
introduced in the commit ea2cdf55e ("MEDIUM: server: Don't introduce a new
server-state file version").
No backport needed.
This revert the commit 63e6cba12 ("MEDIUM: server: add server-states version
2"), but keeping all recent features added to the server-sate file. Instead
of adding a 2nd version for the server-state file format to handle the 5 new
fields added during the 2.4 development, these fields are considered as
optionnal during the parsing. So it is possible to load a server-state file
from HAProxy 2.3. However, from 2.4, these new fields are always dumped in
the server-state file. But it should not be a problem to load it on the 2.3.
This patch seems a bit huge but the diff ignoring the space is much smaller.
The version 2 of the server-state file format is reserved for a real
refactoring to address all issues of the current format.
If a line of a server-state file has too many fields, the last one is not
cut on the first following space, as all other fileds. It contains all the
end of the line. It is not the expected behavior. So, now, we cut it on the
next following space, if any. The parsing loop was slighly rewritten.
Note that for now there is no error reported if the line is too long.
This patch may be backported at least as far as 2.1. On 2.0 and prior the
code is not the same. The line parsing is inlined in apply_server_state()
function.
Same static arrays of parameters are used to parse all server-state
lines. Thus it is important to reinit them to be sure to not get params from
the previous line, eventually from the previous loaded file.
This patch should be backported to all stable branches. However, in 2.0 and
prior, the parsing of server-state lines are inlined in apply_server_state()
function. Thus the patch will have to be adapted on these versions.
When a HTTP return action is triggered, HAProxy is responsible to return the
response, based on the configured status code. On the request side, there is
no problem because there is no server response to replace. But on the
response side, we must take care to override the server response status
code, if any, to be sure to use the rigth status code to get the http reply
message.
In short, we must always set the configured status code of the HTTP return
action before returning the http reply to be sure to get the right reply,
the one base on the http return action status code and not a reply based on
the server response status code..
This patch should fix the issue #1139. It must be backported as far as 2.2.
If a SPOE filter is configured to send its logs to a ring buffer, the
corresponding sink must be resolved during the configuration post
parsing. Otherwise, the sink is undefined when a log message is emitted,
crashing HAProxy.
This patch must be backported as far as 2.2.
Remove ebmb_node entry from struct connection and create a dedicated
struct conn_hash_node. struct connection contains now only a pointer to
a conn_hash_node, allocated only for connections where target is of type
OBJ_TYPE_SERVER. This will reduce memory footprints for every
connections that does not need http-reuse such as frontend connections.
In h2_process there was two parts where the connection was removed from
the idle trees, without first checking if the connection is a backend
side.
This should not produce a crash as the node is properly zeroed on
conn_init. However, it is better to explicit the test as it is done on
all other places. Besides it will be mandatory if the node part is
dynamically allocated only for backend connections.
The maximum number of connections accepted at once by a thread for a single
listener used to default to 64 divided by the number of processes but the
tasklet-based model is much more scalable and benefits from smaller values.
Experimentation has shown that 4 gives the highest accept rate for all
thread values, and that 3 and 5 come very close, as shown below (HTTP/1
connections forwarded per second at multi-accept 4 and 64):
ac\thr| 1 2 4 8 16
------+------------------------------
4| 80k 106k 168k 270k 336k
64| 63k 89k 145k 230k 274k
Some tests were also conducted on SSL and absolutely no change was observed.
The value was placed into a define because it used to be spread all over the
code.
It might be useful at some point to backport this to 2.3 and 2.2 to help
those who observed some performance regressions from 1.6.
SCTL (signed certificate timestamp list) specified in RFC6962
was implemented in c74ce24cd22e8c683ba0e5353c0762f8616e597d, let
us introduce macro HAVE_SSL_SCTL for the HAVE_SSL_SCTL sake,
which in turn is based on SN_ct_cert_scts, which comes in the same commit
we previously forgot to add `agent-*` commands.
Take this opportunity to rewrite the help string in a simpler way for
readability (mainly removing simple quotes)
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Due to the two-phase server reservation, there are 3 calls to
fwlc_srv_reposition() per request, one during assign_server() to reserve
the slot, one in connect_server() to commit it, and one in process_stream()
to release it. However only one of the first two will change the key, so
it's needlessly costly to take the lock, remove a server and insert it
again at the same place when we can already figure we ought not to even
have taken the lock.
Furthermore, even when the server needs to move, there can be quite some
contention on the lbprm lock forcing the thread to wait. During this time
the served and nbpend server values might have changed, just like the
lb_node.key itself. Thus we measure the values again under the lock
before updating the tree. Measurements have shown that under contention
with 16 servers and 16 threads, 50% of the updates can be avoided there.
This patch makes the function compute the new key and compare it to
the current one before deciding to move the entry (and does it again
under the lock forthe second test).
This removes between 40 and 50% of the tree updates depending on the
thread contention and the number of servers. The performance gain due
to this (on 16 threads) was:
16 servers: 415 krps -> 440 krps (6%, contention on lbprm)
4 servers: 554 krps -> 714 krps (+29%, little contention)
One point worth thinking about is that it's not logic to update the
tree 2-3 times per request while it's only read once. half to 2/3 of
these updates are not needed. An experiment consisting in subscribing
the server to a list and letting the readers reinsert them on the fly
showed further degradation instead of an improvement.
A better approach would probably consist in avoinding writes to shared
cache lines by having the leastconn nodes distinct from the servers,
with one node per value, and having them hold an mt-list with all the
servers having that number of connections. The connection count tree
would then be read-mostly instead of facing heavy writes, and most
write operations would be performed on 1-3 list heads which are way
cheaper to migrate than a tree node, and do not require updating the
last two updated neighbors' cache lines.
The operations are only an insert and a delete into the LB tree, which
doesn't require the server's lock at all as the lbprm lock is already
held. Let's drop it. Just for the sake of cleanness, given that the
served and nbpend values used to be atomically updated, we'll use an
atomic load to read them.
The operations are only an insert and a delete into the LB tree, which
doesn't require the server's lock at all as the lbprm lock is already
held. Let's drop it.
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.
In github issue #822, user @ngaugler reported some performance problems when
dealing with many concurrent SSL connections on restarts, after migrating
from 1.6 to 2.2, indicating a long time required to re-establish connections.
The Run_queue metric in the traces showed an abnormally high number of tasks
in the run queue, likely indicating we were accepting faster than we could
process. And this is indeed one of the differences between 1.6 and 2.2, the
accept I/O loop and the TLS handshakes are totally independent, so much that
they can even run on different threads. In 1.6 the SSL handshake was handled
almost immediately after the accept(), so this was limiting the input rate.
With large maxconn values, as long as there are incoming connections, new
I/Os are scheduled and many of them pass before the handshake, being tagged
for low latency processing.
The result is that handshakes get postponed, and are further postponed as
new connections are accepted. When they are finally able to be processed,
some of them fail as the client is gone, and the client had already queued
new ones. This causes an excess number of apparent connections and total
number of handshakes to be processed, just because we were accepting
connections on a temporarily saturated machine.
The solution is to temporarily pause new incoming connections when the
load already indicates that more tasks are already queued than will be
handled in a poll loop. The difficulty with this usually is to be able
to come back to re-enable the operation, but given that the metric is
the run queue, we just have to queue the global_listener_queue task so
that it gets picked by any thread once the run queues get flushed.
Before this patch, injecting with SSL reneg with 10000 concurrent
connections resulted in 350k tasks in the run queue, and a majority of
handshake timeouts noticed by the client. With the patch, the run queue
fluctuates between 1-3x runqueue-depth, the process is constantly busy, the
accept rate is maximized and clients observe no error anymore.
It would be desirable to backport this patch to 2.3 and 2.2 after some more
testing, provided the accept loop there is compatible.
The allowed chunk size was historically limited to 2GB to avoid risk of
overflow. This restriction is no longer necessary because the chunk size is
immediately stored into a 64bits integer after the parsing. Thus, it is now
possible to raise this limit. However to never fed possibly bogus values
from languages that use floats for their integers, we don't get more than 13
hexa-digit (2^52 - 1). 4 petabytes is probably enough !
This patch should fix the issue #1065. It may be backported as far as
2.1. For the 2.0, the legacy HTTP part must be reviewed. But there is
honestely no reason to do so.
A number of traces could be added or changed to report errors with
TRACE_ERROR. The goal is to be able to enable error tracing only to detect
anomalies.
A number of traces could be added or changed to report errors with
TRACE_ERROR. The goal is to be able to enable error tracing only to detect
anomalies.
In order to announce support for the Extended CONNECT h2 method by
haproxy, always send the ENABLE_CONNECT_PROTOCOL h2 settings. This new
setting has been described in the rfc 8441.
After receiving ENABLE_CONNECT_PROTOCOL, the client is free to use the
Extended CONNECT h2 method. This can notably be useful for the support
of websocket handshake on http/2.
Support for the rfc 8441 Bootstraping WebSockets with HTTP/2
Convert an Extended CONNECT HTTP/2 request into a htx representation.
The htx message uses the GET method with an Upgrade header field to be
fully compatible with the equivalent HTTP/1.1 Upgrade mechanism.
The Extended CONNECT is of the following form :
:method = CONNECT
:protocol = websocket
:scheme = https
:path = /chat
:authority = server.example.com
The new pseudo-header :protocol has been defined and is used to identify
an Extended CONNECT method. Contrary to standard CONNECT, Extended
CONNECT must have :scheme, :path and :authority defined.
Add the header Sec-Websocket-Key when generating a h1 handshake websocket
without this header. This is the case when doing h2-h1 conversion.
The key is randomly generated and base64 encoded. It is stored on the session
side to be able to verify response key and reject it if not valid.
Support for the rfc 8441 Bootstraping WebSockets with HTTP/2
Generate an HTTP/2 Extended CONNECT request from a htx Upgrade message.
This conversion is done when seeing the header Connection: Upgrade. A
CONNECT request is written with the :protocol pseudo-header set from the
Upgrade htx header value.
The protocol is saved in the h2s structure. This is needed on the
response side because the protocol is not present on HTTP/2 response but
is needed if the client side is using HTTP/1.1 with 101 status code.
Support for the rfc 8441 Bootstraping WebSockets with HTTP/2
Convert a 200 status reply from an Extended CONNECT request into a htx
representation. The htx message is set to 101 status code to be fully
compatible with the equivalent HTTP/1.1 Upgrade mechanism.
This conversion is only done if the stream flags H2_SF_EXT_CONNECT_SENT
has been set. This is true if an Extended CONNECT request has already
been seen on the stream.
Besides the 101 status, the additional headers Connection/Upgrade are
added to the htx message. The protocol is set from the value stored in
h2s. Typically it will be extracted from the client request. This is
only used if the client is using h1 as only the HTTP/1.1 101 Response
contains the Upgrade header.
This flag is used to signal that an Extended CONNECT has been sent by
the server mux on the current stream.
This will allow to convert the response to a 101 htx status message.
Add the Sec-Websocket-Accept header on a websocket handshake response.
This header may be missing if a h2 server is used with a h1 client.
The response key is calculated following the rfc6455. For this, the
handshake request key must be stored in the h1 session, as a new field
name ws_key. Note that this is only done if the message has been
prealably identified as a Websocket handshake request.
If a request is identified as a WebSocket handshake, it must contains a
websocket key header or else it can be reject, following the rfc6455.
A new flag H1_MF_UPG_WEBSOCKET is set on such messages. For the request
te be identified as a WebSocket handshake, it must contains the headers:
Connection: upgrade
Upgrade: websocket
This commit is a compagnon of
"MEDIUM: h1: generate WebSocket key on response if needed" and
"MEDIUM: h1: add a WebSocket key on handshake if needed".
Indeed, it ensures that a WebSocket key is added only from a http/2 side
and not for a http/1 bogus peer.
The code dealing with the copy of requests in the L7-buffer and the
retransmits during L7 retries has been moved in the HTTP analysers. The copy
is now performed in the REQ_HTTP_XFER_BODY analyser and the L7 retries is
performed in the RES_WAIT_HTTP analyser. This way, si_cs_recv() and
si_cs_send() don't care of it anymore. It is much more natural to deal with
L7 retry in HTTP analysers.
Some responses must not contain data. Reponses to HEAD requests and 204/304
responses. But there is no warranty that this will be really respected by
the senders or even if it is possible. For instance, the method may be
rewritten by an http-request rule (HEAD->GET). Thus, it is not really
possible to always strip these data from the response at the receive
stage. And the response may be emitted by an applet or an internal service
not strictly following the spec. All that to say that we may be prepared to
handle payload for bodyless responses on the sending path.
In addition, unlike the HTTP/1, it is not really clear that the trailers is
part of the payload or not. Thus, some clients may expect to have the
trailers, if any, in the response to a HEAD request. For instance, the GRPC
status is placed in a trailer and clients rely on it. But what happens for
204 responses then. Read the following thread for details :
https://lists.w3.org/Archives/Public/ietf-http-wg/2020OctDec/0040.html
So, thanks to previous patches, it is now possible to know on the sending
path if a response must be bodyless or not. So, for such responses, no DATA
frame is emitted, except eventually the last empty one carring the ES
flag. However, the TRAILERS frames are still emitted. The h2s_skip_data()
function is added to take care to remove HTX DATA blocks without emitting
any DATA frame expect the last one, if there is no trailers.
The H2 message flag H2_MSGF_BODYLESS_RSP is now used during the request or
the response parsing to notify the mux that, considering the parsed message,
the response is known to have no body. This happens during HEAD requests
parsing and during 204/304 responses parsing.
On the H2 multiplexer, the equivalent flag is set on H2 streams. Thus the
H2_SF_BODYLESS_RESP flag is set on a H2 stream if the H2_MSGF_BODYLESS_RSP
is found after a HEADERS frame parsing. Conversely, this flag is also set
when a HEADERS frame is emitted for HEAD requests and for 204/304 responses.
The H2_SF_BODYLESS_RESP flag will be used to ignore data payload from the
response but not the trailers.
No connection header must be added by the H1 mux in 1xx messages, including
101. Existing connection headers remains untouched, especially the "Connection:
upgrade" of 101 responses. This patch only avoids to add "Connection: close" or
"Connection: keep-alive" to 1xx responses.
204 and 1xx responses must not have any payload. Now, the H1 mux takes care
of that in last resort. But they also must not have any C-L or T-E
headers. Thus, if found on the sending path, these headers are ignored.
Some responses must not contain data. Reponses to HEAD requests and 204/304
xresponses. But there is no warranty that this will be really respected by
the senders or even if it is possible. For instance, the method may be
rewritten by an http-request rule (HEAD->GET). Thus, it is not really
possible to always strip the payload from the response at the receive
stage. And the response may be emitted by an applet or an internal service
not strictly following the spec. All that to say that we may be prepared to
handle payload for bodyless responses on the sending path.
So, thanks to previous patches, it is now possible to know on the sending
path if a response must be bodyless or not. So, for such responses, no
payload is emitted, all HTX blocks after the EOH are silently removed
(including the trailers).
In HTTP/1, responses to HEAD requests and 204/304 must not have payload. The
H1S_F_BODYLESS_RESP flag is not set on streams that should handle such
responses, on the client side and the server side.
On the client side, this flag is set when a HEAD request is parsed and when
a 204/304 response is emitted. On the server side, this happends when a HEAD
request is emitted or a 204/304 response is parsed.
The EOM block may be removed. The HTX_FL_EOM flags is enough. Most of time,
to know if the end of the message is reached, we just need to have an empty
HTX message with HTX_FL_EOM flag set. It may also be detected when the last
block of a message with HTX_FL_EOM flag is manipulated.
Removing EOM blocks simplifies the HTX message filling. Indeed, there is no
more edge problems when the message ends but there is no more space to write
the EOM block. However, some part are more tricky. Especially the
compression filter or the FCGI mux. The compression filter must finish the
compression on the last DATA block. Before it was performed on the EOM
block, an extra DATA block with the checksum was added. Now, we must detect
the last DATA block to be sure to finish the compression. The FCGI mux on
its part must be sure to reserve the space for the empty STDIN record on the
last DATA block while this record was inserted on the EOM block.
The H2 multiplexer is probably the part that benefits the most from this
change. Indeed, it is now fairly easier to known when to set the ES flag.
The HTX documentaion has been updated accordingly.
Tunnel management between the H1 and H2 multiplexers is a bit blurred. And
the HTX is not enough well defined on this point to make things clear. In
fact, Establishing a tunnel between an H2 client and an H1 server, or the
opposite is buggy because the both multiplexers don't handle the EOM block
the same way when a tunnel is established. In fact, the H2 multiplexer is
pretty strict and add an END_STREAM flag when an EOM block is found, while
the H1 multiplexer is more flexible.
The purpose of this patch is to make the EOM block usage pretty clear and to
fix the HTTP multiplexers to really handle HTTP tunnels in the right
way. Now, an EOM block is used to mark the end of an HTTP message,
semantically speaking. That means it may be followed by tunneled data. Thus,
CONNECT requests are now finished by an EOM block, just after the EOH block.
On the H1 multiplexer side, a tunnel is now only established on the response
path. So a CONNECT request remains in a DONE state waiting for the 2xx
response. On the H2 multiplexer side, a flag is used to know an HTTP tunnel
is requested, to not immediately add the END_STREAM flag on the EOM block.
All these changes are sensitives and not backportable because of recent
changes. The same problem exists on earlier versions and should be
addressed. But it will only be possible with a specific patchset.
This patch relies on the following ones :
* MEDIUM: mux-h1: Properly handle tunnel establishments and aborts
* MEDIUM: mux-h2: Close streams when processing data for an aborted tunnel
* MEDIUM: mux-h2: Block client data on server side waiting tunnel establishment
* MINOR: mux-h2: Add 2 flags to help to properly handle tunnel mode
* MINOR: mux-h1: Split H1C_F_WAIT_OPPOSITE flag to separate input/output sides
* MINOR: mux-h1/mux-fcgi: Don't set TUNNEL mode if payload length is unknown
In the same way than the H2 mux, we now bloc data sending on the server side
if a tunnel is not fully established. In addition, if some data are still
pending for a aborted tunnel, an error is triggered and the server
connection is closed.
To do so, we rely on the H1C_F_WAIT_INPUT flag to bloc the output
processing. This patch contributes to fix the tunnel mode between the H1 and
the H2 muxes.
In the previous patch ("MEDIUM: mux-h2: Block client data on server side
waiting tunnel establishment"), we added a way to block client data for not
fully established tunnel on the server side. This one closes the stream with
an ERR_CANCEL erorr if there are some pending tunneled data while the tunnel
was aborted. This may happen on the client side if a non-empty DATA frame or
an empty DATA frame without the ES flag is received. This may also happen on
the server side if there is a DATA htx block. However in this last case, we
first wait the response is fully forwarded.
This patch contributes to fix the tunnel mode between the H1 and the H2
muxes.
