When we leave the I/O handler with an unfinished request, we must report the
applet has more data to deliver. Otherwise, when the channel request buffer
is emptied, the http-client applet is not always woken up to forward the
remaining request data.
This issue was probably revealed by commit "BUG/MEDIUM: http-client: Don't
wake http-client applet if nothing was xferred". It is only an issue with
large POSTs, when the payload is streamed.
This patch must be backported as far as 2.6 with the commit above. But on
older versions, the applet API may differ. So be careful.
When a large request is sent, it is possible to have a response before the
end of the request. It is valid from HTTP perspective but it is an issue
with the current design of the http-client. Indded, the request and the
response are handled sequentially. So the response will be blocked, waiting
for the end of the request. Most of time, it is not an issue, except when
the request transfer is blocked. In that case, the applet is blocked.
With the current API, it is not possible to handle early response and
continue the request transfer. So, this case cannot be handle. In that case,
it seems reasonnable to drain the request if a response is received. This
way, the request transfer, from the caller point of view, is never blocked
and the response can be properly processed.
To do so, the action flag HTTPCLIENT_FA_DRAIN_REQ is added to the
http-client. When it is set, the request payload is just dropped. In that
case, we take care to not report the end of input to properly report the
request was truncated, especially in logs.
It is only an issue with large POSTs, when the payload is streamed.
This patch must be backported as far as 2.6.
Protocol updages are not supported by the http-client. So report an error is
a 101-switching-protocols response is received. Of course, it is unexpected
because the API is not designed to support upgrades. But it is better to
properly handle this case.
This patch could be backported as far as 2.6. It depends on the commit
"BUG/MINOR: http-client: Ignore 1XX interim responses in non-HTX mode".
When the response is re-formatted in raw message, the 1XX interim responses
must be skipped. Otherwise, information of the first interim response will
be saved (status line and headers) and those from the final response will be
dropped.
Note that for now, in HTX-mode, the interim messages are removed.
This patch must be backported as far as 2.6.
when htx_to_buf() function is called, if the HTX message is empty, the
buffer is reset. So HTX flags must not be tested after because the info may
be lost.
So now, we take care to test HTX_FL_EOM flag before calling htx_to_buf().
This patch must be backported as far as 2.8.
When the request payload cannot be xferred to the channel because its buffer
is full, we must request for more room by calling sc_need_room(). It is
important to be sure the httpclient applet will not be woken up in loop to
push more data while it is not possible.
It is only an issue with large POSTs, when the payload is streamed.
This patch must be backported as far as 2.6. Note that on 2.6,
sc_need_room() only takes one argument.
When HTX blocks from the requests are transferred into the channel buffer,
the return value of htx_xfer_blks() function must not be used to increment
the channel input value because meta data are counted here while they are
not part of input data. Because of this bug, it is possible to forward more
data than these present in the channel buffer.
Instead, we look at the input data before and after the transfer and the
difference is added.
It is only an issue with large POSTs, when the payload is streamed.
This patch must be backported as far as 2.6.
When data are transferred to or from the htt-pclient, the applet is
systematically woken up, even when no data are transferred. This could lead
to needlessly wakeups. When called from a lua script, if data are blocked
for a while, this leads to a wakeup ping-pong loop where the http-client
applet is woken up by the lua script which wakes back the script.
To fix the issue, in httpclient_req_xfer() and httpclient_res_xfer()
functions, we now take care to not wake the http-client applet up when no
data are transferred.
This patch must be backported as far as 2.6.
This introduce a change of behavior in the httpclient API. When
generating a request with a payload buffer, the size of the buffer
payload is known and does not need to be streamed in chunks.
This patch force to sends payload buffer using a Content-Length header
in the request, however the behavior does not change if a callback is
still used instead of a buffer.
Add a HTTPCLIENT_O_RES_HTX flag which allow to store directly the HTX
data in the response buffer instead of extracting the data in raw
format.
This is useful when the data need to be reused in another request.
This patch split the httpclient code to prevent confusion between the
httpclient CLI command and the actual httpclient API.
Indeed there was a confusion between the flag used internally by the
CLI command, and the actual httpclient API.
hc_cli_* functions as well as HC_C_F_* defines were moved to
httpclient_cli.c.
The HC_F_HTTPPROXY flag was wrongly named and does not use the correct
value, indeed this flag was meant to be used for the httpclient API, not
the httpclient CLI.
This patch fixes the problem by introducing HTTPCLIENT_FO_HTTPPROXY
which has must be set in hc->flags.
Also add a member 'options' in the httpclient structure, because the
member flags is reinitialized when starting.
Must be backported as far as 3.0.
while new_server() takes the parent proxy as argument and even assigns
srv->proxy to the parent proxy, it didn't actually inserted the server
to the parent proxy server list on success.
The result is that sometimes we add the server to the list after
new_server() is called, and sometimes we don't.
This is really error-prone and because of that hooks such as
REGISTER_POST_SERVER_CHECK() which as run for all servers listed in
all proxies may not be relied upon for servers which are not actually
inserted in their parent proxy server list. Plus it feels very strange
to have a server that points to a proxy, but then the proxy doesn't know
about it because it cannot find it in its server list.
To prevent errors and make proxy->srv list reliable, we move the insertion
logic directly under new_server(). This requires to know if we are called
during parsing or during runtime to either insert or append the server to
the parent proxy list. For that we use PR_FL_CHECKED flag from the parent
proxy (if the flag is set, then the proxy was checked so we are past the
init phase, thus we assume we are called during runtime)
This implies that during startup if new_server() has to be cancelled on
error paths we need to call srv_detach() (which is now exposed in server.h)
before srv_drop().
The consequence of this commit is that REGISTER_POST_SERVER_CHECK() should
not run reliably on all servers created using new_server() (without having
to manually loop on global servers_list)
Since commit fe75c1e12d ("MEDIUM: startup: remove
MODE_MWORKER_WAIT") the MODE_MWORKER_WAIT constant disappearded. The
initialization of the httpclient proxy was conditionned by this
constant.
The proxy must be created in mworker mode, but only in the worker not in
the master. It was currently completely disabled in both the master and
the worker provoking a NULL dereference upon httpclient usage.
No backport needed.
Latest patches on the mworker rework skipped the httpclient_proxy
creation by accident. This is not supposed to happen because haproxy is
supposed to stop when the proxy creation failed, but it shows a flaw in
the API.
When the httpclient_proxy or the proxy used in parameter of
httpclient_new_from_proxy() is NULL, it will be dereferenced and cause a
crash.
The patch only returns a NULL when doing an httpclient_new() if the
proxy is not available.
Must be backported as far as 2.7.
MODE_MWORKER_WAIT becames redundant with MODE_MWORKER, due to moving
master-worker fork in init(). This change allows master no longer perform
reexec just after forking in order to free additional memory.
As after the fork in the master process we set 'master' variable, we can
replace now MODE_MWORKER_WAIT in some 'if' statements by simple check of this
'master' variable.
Let's also continue to get rid of HAPROXY_MWORKER_WAIT_ONLY environment
variable, as it's no longer needed as well.
In cfg_program_postparser(), which is used to check if cmdline is defined to
launch a program, we completely remove the check of mode for now, because
the master process does not parse the configuration for the moment. 'program'
section parsing will be reintroduced in master later in the next commits.
Add a new parameter "alt" that will store wether this configuration
use an alternate protocol.
This alt pointer will contain a value that can be transparently
passed to protocol_lookup to obtain an appropriate protocol structure.
This change is needed to allow for example the servers to know if it
need to use an alternate protocol or not.
Define a new server keyword pool-conn-name. The purpose of this keyword
will be to identify connections inside the idle connections pool,
replacing SNI in case SSL is not wanted.
This keyword uses a sample expression argument. It thus can reuse
existing function parse_srv_expr() for parsing. In the future, it may be
necessary to define a keyword variant which uses a logformat for
extensability.
This patch only implement parsing. Argument is stored inside new server
field <pool_conn_name> and expression is generated in
_srv_parse_finalize() into <pool_conn_name_expr>.
If pool-conn-name is not set but SNI is, the latter is reused
automatically as pool-conn-name via _srv_parse_finalize(). This ensures
current reuse behavior remains compatible and idle connection reuse will
not mix connections with different SNIs by mistake.
Main usage will be for rhttp when SSL is not wanted between the two
haproxy instances. Previously, it was possible to use "sni" keyword even
without SSL on a server line which have a similar effect. However,
having a dedicated "pool-conn-name" keyword is deemed clearer. Besides,
it would allow for more complex configuration where pool-conn-name and
SNI are use in parallel with different values.
Two functions exists for server sni sample expression parsing. This is
confusing so this commit aims at clarifying this.
Functions are renamed with the following identifiers. First function is
named parse_srv_expr() and can be used during parsing. Besides
expression parsing, it has ensure sample fetch validity in the context
of a server line.
Second function is renamed _parse_srv_expr() and is used internally by
parse_srv_expr(). It only implements sample parsing without extra
checks. It is already use for server instantiation derived from
server-template as checks were already performed. Also, it is now used
in http-client code as SNI is a fixed string.
Finally, both functions are generalized to remove any reference to SNI.
This will allow to reuse it to parse other server keywords which use an
expression. This will be the case for the future keyword pool-conn-name.
The goal is to indicate how critical the allocation is, between the
least one (growing an existing buffer ring) and the topmost one (boot
time allocation for the life of the process).
The 3 tcp-based muxes (h1, h2, fcgi) use a common allocation function
to try to allocate otherwise subscribe. There's currently no distinction
of direction nor part that tries to allocate, and this should be revisited
to improve this situation, particularly when we consider that mux-h2 can
reduce its Tx allocations if needed.
For now, 4 main levels are planned, to translate how the data travels
inside haproxy from a producer to a consumer:
- MUX_RX: buffer used to receive data from the OS
- SE_RX: buffer used to place a transformation of the RX data for
a mux, or to produce a response for an applet
- CHANNEL: the channel buffer for sync recv
- MUX_TX: buffer used to transfer data from the channel to the outside,
generally a mux but there can be a few specificities (e.g.
http client's response buffer passed to the application,
which also gets a transformation of the channel data).
The other levels are a bit different in that they don't strictly need to
allocate for the first two ones, or they're permanent for the last one
(used by compression).
Currently, the way proxy-oriented logformat directives are handled is way
too complicated. Indeed, "log-format", "log-format-error", "log-format-sd"
and "unique-id-format" all rely on preparsing hints stored inside
proxy->conf member struct. Those preparsing hints include the original
string that should be compiled once the proxy parameters are known plus
the config file and line number where the string was found to generate
precise error messages in case of failure during the compiling process
that happens within check_config_validity().
Now that lf_expr API permits to compile a lf_expr struct that was
previously prepared (with original string and config hints), let's
leverage lf_expr_compile() from check_config_validity() and instead
of relying on individual proxy->conf hints for each logformat expression,
store string and config hints in the lf_expr struct directly and use
lf_expr helpers funcs to handle them when relevant (ie: original
logformat string freeing is now done at a central place inside
lf_expr_deinit(), which allows for some simplifications)
Doing so allows us to greatly simplify the preparsing logic for those 4
proxy directives, and to finally save some space in the proxy struct.
Also, since httpclient proxy has its "logformat" automatically compiled
in check_config_validity(), we now use the file hint from the logformat
expression struct to set an explicit name that will be reported in case
of error ("parsing [httpclient:0] : ...") and remove the extraneous check
in httpclient_precheck() (logformat was parsed twice previously..)
This patch tries to address a design flaw with how logformat expressions
are parsed from config. Indeed, some parse_logformat_string() calls are
performed during config parsing when the proxy mode is not yet known.
Here's a config example that illustrates the issue:
defaults
mode tcp
listen test
bind :8888
http-response set-header custom-hdr "%trl" # needs http
mode http
The above config should work, because the effective proxy mode is http,
yet haproxy fails with this error:
[ALERT] (99051) : config : parsing [repro.conf:6] : error detected in proxy 'test' while parsing 'http-response set-header' rule : format tag 'trl' is reserved for HTTP mode.
To fix the issue once and for all, let's implement smart postparsing for
logformat expressions encountered during config parsing:
- split parse_logformat_string() (and subfonctions) in order to create a
new lf_expr_postcheck() function that must be called to finish
preparing and checking the logformat expression once the proxy type is
known.
- save some config hints info during parse_logformat_string() to
generate more precise error messages during lf_expr_postcheck(), if
needed, we rely on curpx->conf.args.{file,line} hints for that because
parse_logformat_string() doesn't know about current file and line
number.
- lf_expr_postcheck() uses PR_FL_CHECKED proxy flag to know if the
function may try to make the proxy compatible with the expression, or
if it should simply fail as soon as an incompatibility is detected.
- if parse_logformat_string() is called from an unchecked proxy, then
schedule the expression for postparsing, else (ie: during runtime),
run the postcheck right away.
This change will also allow for some logformat expression error handling
simplifications in the future.
It is the third applet to be refactored to use its own buffers. In addition to
the CLI applet, some I/O handlers of CLI commands were also updated, especially
the stats ones.
Some command I/O handlers were updated to use applet's buffers instead of
channels ones.
httpclient_precheck(), ssl_ocsp_update_precheck(), and
resolvers_create_default() functions are registered through
REGISTER_PRE_CHECK() macro to be called by haproxy during init from the
pre_check_list list. When calling functions registered in pre_check_list,
haproxy expects ERR_* return values. However those 3 functions currently
use raw return values, so we better use explicit ERR_* macros to prevent
breakage in the future if ERR_* values mapping were to change.
These both flags are set after releasing the applet, in
appctx_shut(). Concretly, it means the applet is shutdown for reads and
writes. Once set, the applet's I/O handler was no longer called. Tests on
these flags are useless. There is no chance to match them.
It's useful to be able to recognize certain functions that are often
present in backtraces as they call lower level functions, and for this
they must not be static. Let's remove "static" in front of these
functions:
sc_notify, sc_conn_recv, sc_conn_send, sc_conn_process,
sc_applet_process, back_establish, stream_update_both_sc,
httpclient_applet_io_handler, httpclient_applet_init,
httpclient_applet_release
The proxy's initialization is rather odd. First, init_new_proxy() is
called to zero all the lists and certain values, except those that can
come from defaults, which are initialized by proxy_preset_defaults().
The default server settings are also only set there.
This results in these settings not to be set for a number of internal
proxies that do not explicitly call proxy_preset_defaults() after
allocation, such as sink and log forwarders.
This was revealed by last commit 79aa63823 ("MINOR: server: always
initialize pp_tlvs for default servers") which crashes in log parsers
when applied to certain proxies which did not initialize their default
servers.
In theory this should be backported, however it would be desirable to
wait a bit before backporting it, in case certain parts would rely on
these elements not being initialized.
str2sa_range() already allows the caller to provide <proto> in order to
get a pointer on the protocol matching with the string input thanks to
5fc9328a ("MINOR: tools: make str2sa_range() directly return the protocol")
However, as stated into the commit message, there is a trick:
"we can fail to return a protocol in case the caller
accepts an fqdn for use later. This is what servers do and in this
case it is valid to return no protocol"
In this case, we're unable to return protocol because the protocol lookup
depends on both the [proto type + xprt type] and the [family type] to be
known.
While family type might not be directly resolved when fqdn is involved
(because family type might be discovered using DNS queries), proto type
and xprt type are already known. As such, the caller might be interested
in knowing those address related hints even if the address family type is
not yet resolved and thus the matching protocol cannot be looked up.
Thus in this patch we add the optional net_addr_type (custom type)
argument to str2sa_range to enable the caller to check the protocol type
and transport type when the function succeeds.
When 'log' directive was implemented, the internal representation was
named 'struct logsrv', because the 'log' directive would directly point
to the log target, which used to be a (UDP) log server exclusively at
that time, hence the name.
But things have become more complex, since today 'log' directive can point
to ring targets (implicit, or named) for example.
Indeed, a 'log' directive does no longer reference the "final" server to
which the log will be sent, but instead it describes which log API and
parameters to use for transporting the log messages to the proper log
destination.
So now the term 'logsrv' is rather confusing and prevents us from
introducing a new level of abstraction because they would be mixed
with logsrv.
So in order to better designate this 'log' directive, and make it more
generic, we chose the word 'logger' which now replaces logsrv everywhere
it was used in the code (including related comments).
This is internal rewording, so no functional change should be expected
on user-side.
httpclient used to register a global post-check function to iterate over
all known proxies and post-initialize httpclient related ones (mainly
for logs initialization).
But we currently have an issue: post_sink_resolve() function which is
also registered using REGISTER_POST_CHECK() macro conflicts with
httpclient_postcheck() function.
This is because post_sink_resolve() relies on proxy->logsrvs to be
correctly initialized already, and httpclient_postcheck() may create
and insert new logsrvs entries to existing proxies when executed.
So depending on which function runs first, we could run into trouble.
Hopefully, to this day, everything works "by accident" due to
http_client.c file being loaded before sink.c file when compiling source
code.
But as soon as we would move one of the two functions to other files, or
if we rename files or make changes to the Makefile build recipe, we could
break this at any time.
To prevent post_sink_resolve() from randomly failing in the future, we now
make httpclient postcheck rely on per-proxy post-checks by slightly
modifying httpclient_postcheck() function so that it can be registered
using REGISTER_POST_PROXY_CHECK() macro.
As per-proxy post-check functions are executed right after config parsing
for each known proxy (vs global post-check which are executed a bit later
in the init process), we can be certain that functions registered using
global post-check macro, ie: post_sink_resolve(), will always be executed
after httpclient postcheck, effectively resolving the ordering conflict.
This should normally not cause visible behavior changes, and while it
could be considered as a bug, it's probably not worth backporting it
since the only way to trigger the issue is through code refactors,
unless we want to backport it to ease code maintenance of course,
in which case it should easily apply for >= 2.7.
When using the httpclient, one could be bothered with it returning
after a very long time when failing. By default the httpclient has a
retries of 3 and a timeout connect of 5s, which can results in pause of
20s upon failure.
This patch allows the user to configure the "timeout connect" of the
httpclient so it could reduce the time to return an error.
This patch helps fixing part of the issue #2269.
Could be backported in 2.7 if needed.
When using the httpclient, one could be bothered with it returning after
a very long time when failing. By default the httpclient has a retries
of 3 and a timeout connect of 5s, which can results in pause of 20s
upon failure.
This patch allows the user to configure the retries of the httpclient so
it could reduce the time to return an error.
This patch helps fixing part of the issue #2269.
Could be backported in 2.7 if needed.
In the http-client I/O handler, HTX request and response are loaded from the
channels buffer. Some changes are preformed in these messages. So, we must
take care to commit changes into the underlying buffer by calling
htx_to_buf().
It is especially important when the HTX message becoms empty to be able to
quickly release the buffer.
This patch should be backported as far as 2.6.
httpclient.resolvers.disabled allow to disable completely the resolvers
of the httpclient, prevents the creation of the "default" resolvers
section, and does not insert the http do-resolve rule in the proxies.
sc_need_room() now takes the required free space to receive more data as
parameter. All calls to this function are updated accordingly. For now, this
value is set but not used. When we are waiting for a buffer, 0 is used. So
we expect to be unblocked ASAP. However this must be reviewed because
SC_FL_NEED_BUF is probably enough in this case and this flag is already set
if the input buffer allocation fails.
When the http-client applet is executed while a shut is pending, the
remaining output data must always be consumed. Otherwise, this can prevent
the stream to exit, leading to a spinning loop on the applet.
It is 2.8-specific. No backport needed.
Just like for other applets, we now use the SE descriptor instead of the
channel to report error and end-of-stream. Here, the applet is a bit
refactored to handle SE descriptor EOS, EOI and ERROR flags
Thanks to the previous patch, it is now possible for applets to not set the
CF_EOI flag on the channels. On this point, the applets get closer to the
muxes.
Read and write timeouts (.rto and .wto) are now replaced by an unique
timeout, call .ioto. Since the recent refactoring on channel's timeouts,
both use the same value, the client timeout on client side and the server
timeout on the server side. Thus, this part may be simplified. Now it
represents the I/O timeout.
Read and write timeouts concerns the I/O. Thus, it is logical to move it into
the stconn. At the end, the stream is responsible to detect the timeouts. So
it is logcial to have these values in the stconn and not in the SE
descriptor. But it may change depending on the recfactoring.
So, now:
* scf->rto is used instead of req->rto
* scf->wto is used instead of res->wto
* scb->rto is used instead of res->rto
* scb->wto is used instead of req->wto
The httpclient emits logs in the httplog format, however it still
display the frontend, the backend and the server.
In the case of the httpclient we only need to know that we are using the
httpclient, so the backend and server information are irelevant.
In the case of extra code the name of the proxy can be long and will be
displayed twice which is not useful.
This is the same log-format as the httplog but the %b/%s is now -/- so
the format is still compatible with an httplog parser.
Before:
<134>Dec 22 15:19:27 haproxy[1013520]: -:- [22/Dec/2022:15:19:27.482] <HTTPCLIENT> <HTTPCLIENT>/<HTTPCLIENT> 2/0/4/6/10 200 848 - - ---- 0/0/0/0/0 0/0 {92.123.236.161} "GET http://r3.o.lencr.org/1234 HTTP/1.1"
After:
<134>Dec 22 15:19:27 haproxy[1013520]: -:- [22/Dec/2022:15:19:27.482] <HTTPCLIENT> -/- 2/0/4/6/10 200 848 - - ---- 0/0/0/0/0 0/0 {92.123.236.161} "GET http://r3.o.lencr.org/1234 HTTP/1.1"
Don't try to create a request with a body in httpclient_req_gen() if the
payload ist has a ptr but no len.
Sometimes people have their httpclient stuck because they use an ist
with a data ptr but no len. Check the len so this mistake doesn't block
the client.
With an OpenSSL library which use the wrong OPENSSLDIR, HAProxy tries to
load the OPENSSLDIR/certs/ into @system-ca, but emits a warning when it
can't.
This patch fixes the issue by allowing to shut the error when the SSL
configuration for the httpclient is not explicit.
Must be backported in 2.6.
The memory for the SSL ca_file was allocated only once (in the function
httpclient_create_proxy()) and that pointer was assigned to each created
proxy that the HTTP client uses. This would not be a problem if this
memory was not freed in each individual proxy when it was deinitialized
in the function ssl_sock_free_srv_ctx().
Memory allocation:
src/http_client.c, function httpclient_create_proxy():
1277: if (!httpclient_ssl_ca_file)
1278: httpclient_ssl_ca_file = strdup("@system-ca");
1280: srv_ssl->ssl_ctx.ca_file = httpclient_ssl_ca_file;
Memory deallocation:
src/ssl_sock.c, function ssl_sock_free_srv_ctx():
5613: ha_free(&srv->ssl_ctx.ca_file);
This should be backported to version 2.6.
Upon a applet_release(), the applet can be scheduled again and a call to
the IO handler is still possible. When the struct httpclient is already
free the IO handler could try to access it.
This patch fixes the issue by setting svcctx to NULL in the
applet_release, and checking its value in the IO handler.
Must be backported as far as 2.5.
