There was a special case made to allow ARMv6 to use unaligned accesses
via a cast in xxHash when __ARM_FEATURE_UNALIGNED is defined. But while
ARMv6 (and v7) does support unaligned accesses, it's only for 32-bit
pointers, not 64-bit ones, leading to bus errors when the compiler emits
an ldrd instruction and the input (e.g. a pattern) is not aligned, as in
issue #1035.
Note that v7 was properly using the packed approach here and was safe,
however haproxy versions 2.3 and older use the old r39 xxhash code which
has the same issue for armv7. A slightly different fix is required there,
by using a different definition of packed for 32 and 64 bits.
The problem is really visible when running v7 code on a v8 kernel because
such kernels do not implement alignment trap emulation, and the process
dies when this happens. This is why in the issue above it was only detected
under lxc. The emulation could have been disabled on v7 as well by writing
zero to /proc/cpu/alignment though.
This commit is a backport of xxhash commit a470f2ef ("update default memory
access for armv6").
Thanks to @srkunze for the report and tests, @stgraber for his help on
setting up an easy reproducer outside of lxc, and @Cyan4973 for the
discussion around the best way to fix this. Details and alternate patches
available on https://github.com/Cyan4973/xxHash/issues/490.
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>
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.
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.
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.
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
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.
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 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.
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.
The htx_is_unique_blk() function may now be used to know if a block is the
only one in an HTX message, excluding all unused blocks. Note the purpose of
this function is not to know if a block is the last one of an HTTP message.
This means no more data part from the message are expected, except tunneled
data. It only says if a block is alone in an HTX message.
Add an HTX start-line flag and its counterpart into the HTTP message to
track the presence of the Upgrade option into the Connection header. This
way, without parsing the Connection header again, it will be easy to know if
a client asks for a protocol upgrade and if the server agrees to do so. It
will also be easy to perform some conformance checks when a
101-switching-protocols is received.
TCP to H1 upgrades are buggy for now. When such upgrade is performed, a
crash is experienced. The bug is the result of the recent H1 mux
refactoring, and more specifically because of the commit c4bfa59f1 ("MAJOR:
mux-h1: Create the client stream as later as possible"). Indeed, now the H1
mux is responsible to create the frontend conn-stream once the request
headers are fully received. Thus the TCP to H1 upgrade is a problem because
the frontend conn-stream already exists.
To fix the bug, we must keep this conn-stream and the associate stream and
use it in the H1 mux. To do so, the upgrade will be performed in two
steps. First, the mux is upgraded from mux-pt to mux-h1. Then, the mux-h1
performs the stream upgrade, once the request headers are fully received and
parsed. To do so, stream_upgrade_from_cs() must be used. This function set
the SF_HTX flags to switch the stream to HTX mode, it removes the SF_IGNORE
flags and eventually it fills the request channel with some input data.
This patch is required to fix the TCP to H1 upgrades and is intimately
linked with the next commits.
A bug was introduced by the early insertion of idle connections at the
end of connect_server. It is possible to reuse a connection not yet
ready waiting for an handshake (for example with proxy protocol or ssl).
A wrong duplicate xprt_handshake_io_cb tasklet is thus registered as a
side-effect.
This triggers the BUG_ON statement of xprt_handshake_subscribe :
BUG_ON(ctx->subs && ctx->subs != es);
To counter this, a check is now present in session_get_conn to only
return a connection without the flag CO_FL_WAIT_XPRT. This might cause
sometimes the creation of dedicated server connections when in theory
reuse could have been used, but probably only occurs rarely in real
condition.
This behavior is present since commit :
MEDIUM: connection: Add private connections synchronously in session server list
It could also be further exagerated by :
MEDIUM: backend: add reused conn to sess if mux marked as HOL blocking
It can be backported up to 2.3.
NOTE : This bug seems to be only reproducible with mode tcp, for an
unknown reason. However, reuse should never happen when not in http
mode. This improper behavior will be the subject of a dedicated patch.
This bug can easily be reproducible with the following config (a
webserver is required to accept proxy protocol on port 31080) :
global
defaults
mode tcp
timeout connect 1s
timeout server 1s
timeout client 1s
listen li
bind 0.0.0.0:4444
server bla1 127.0.0.1:31080 check send-proxy-v2
with the inject client :
$ inject -u 10000 -d 10 -G 127.0.0.1:4444
This should fix the github issue #1058.
Building with `"DEBUG=-DDEBUG_STRICT=1 -DDEBUG_USE_ABORT=1"` previously emitted the warning:
In file included from include/haproxy/api.h:35:0,
from src/mux_pt.c:13:
include/haproxy/buf.h: In function ‘br_init’:
include/haproxy/bug.h:42:90: warning: implicit declaration of function ‘abort’ [-Wimplicit-function-declaration]
#define ABORT_NOW() do { extern void ha_backtrace_to_stderr(); ha_backtrace_to_stderr(); abort(); } while (0)
^
include/haproxy/bug.h:56:21: note: in expansion of macro ‘ABORT_NOW’
#define CRASH_NOW() ABORT_NOW()
^
include/haproxy/bug.h:68:4: note: in expansion of macro ‘CRASH_NOW’
CRASH_NOW(); \
^
include/haproxy/bug.h:62:35: note: in expansion of macro ‘__BUG_ON’
#define _BUG_ON(cond, file, line) __BUG_ON(cond, file, line)
^
include/haproxy/bug.h:61:22: note: in expansion of macro ‘_BUG_ON’
#define BUG_ON(cond) _BUG_ON(cond, __FILE__, __LINE__)
^
include/haproxy/buf.h:875:2: note: in expansion of macro ‘BUG_ON’
BUG_ON(size < 2);
^
This patch fixes that issue. The `DEBUG_USE_ABORT` option exists for use with
static analysis tools. No backport needed.
Since the server SSL_CTX is now stored in the ckch_inst, it is not
needed anymore to pass an SSL_CTX to ckch_inst_new_load_srv_store() and
ssl_sock_load_srv_ckchs().
The client_crt member is not used anymore since the server's ssl context
initialization now behaves the same way as the bind lines one (using
ckch stores and instances).
When trying to update a backend certificate, we should find a
server-side ckch instance thanks to which we can rebuild a new ssl
context and a new ckch instance that replace the previous ones in the
server structure. This way any new ssl session will be built out of the
new ssl context and the newly updated certificate.
This resolves a subpart of GitHub issue #427 (the certificate part)
In order for the backend server's certificate to be hot-updatable, it
needs to fit into the implementation used for the "bind" certificates.
This patch follows the architecture implemented for the frontend
implementation and reuses its structures and general function calls
(adapted for the server side).
The ckch store logic is kept and a dedicated ckch instance is used (one
per server). The whole sni_ctx logic was not kept though because it is
not needed.
All the new functions added in this patch are basically server-side
copies of functions that already exist on the frontend side with all the
sni and bind_cond references removed.
The ckch_inst structure has a new 'is_server_instance' flag which is
used to distinguish regular instances from the server-side ones, and a
new pointer to the server's structure in case of backend instance.
Since the new server ckch instances are linked to a standard ckch_store,
a lookup in the ckch store table will succeed so the cli code used to
update bind certificates needs to be covered to manage those new server
side ckch instances.
Split the server's ssl context initialization into the general ssl
related initializations and the actual initialization of a single
SSL_CTX structure. This way the context's initialization will be
usable by itself from elsewhere.
It is only a problem on the response path because the request payload length
it always known. But when a filter is registered to analyze the response
payload, the filtering may hang if the server closes just after the headers.
The root cause of the bug comes from an attempt to allow the filters to not
immediately forward the headers if necessary. A filter may choose to hold
the headers by not forwarding any bytes of the payload. For a message with
no payload but a known payload length, there is always a EOM block to
forward. Thus holding the EOM block for bodyless messages is a good way to
also hold the headers. However, messages with an unknown payload length,
there is no EOM block finishing the message, but only a SHUTR flag on the
channel to mark the end of the stream. If there is no payload when it
happens, there is no payload at all to forward. In the filters API, it is
wrongly detected as a condition to not forward the headers.
Because it is not the most used feature and not the obvious one, this patch
introduces another way to hold the message headers at the begining of the
forwarding. A filter flag is added to explicitly says the headers should be
hold. A filter may choose to set the STRM_FLT_FL_HOLD_HTTP_HDRS flag and not
forwad anything to hold the headers. This flag is removed at each call, thus
it must always be explicitly set by filters. This flag is only evaluated if
no byte has ever been forwarded because the headers are forwarded with the
first byte of the payload.
reg-tests/filters/random-forwarding.vtc reg-test is updated to also test
responses with unknown payload length (with and without payload).
This patch must be backported as far as 2.0.
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.
This patch follows what has already been done on frontend and backend
side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the server.
A few things to note though:
- state require prior calculation, so I moved that to a sort of helper
`stats_fill_be_stats_computestate`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
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.
This patch follows what has already been done on frontend side.
From this patch it should be possible to remove most of the duplicate
code on prometheuse side for the backend
A few things to note though:
- status and uweight field requires prior compute, so I moved that to a
sort of helper `stats_fill_be_stats_computesrv`.
- all ST_F*TIME fields requires some minor compute, so I moved it at te
beginning of the function under a condition.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
while working on backend/servers I realised I could have written that in
a better way and avoid one extra break. This is slightly improving
readiness.
also while being here, fix function declaration which was not 100%
accurate.
this patch does not change the behaviour of the code.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
The dump state is now passed to the function so that the caller can adjust
the behavior. A new series of 4 values allow to stop *after* dumping main
instead of before it or any of the usual loops. This allows to also report
BUG_ON() that could happen very high in the call graph (e.g. startup, or
the scheduler itself) while still understanding what the call path was.
The purpose is to enable the dumping of a backtrace on BUG_ON(). While
it's very useful to know that a condition was met, very often some
caller context is missing to figure how the condition could happen.
From now on, on systems featuring backtrace, a backtrace of the calling
thread will also be dumped to stderr in addition to the unexpected
condition. This will help users of DEBUG_STRICT as they'll most often
find this backtrace in their logs even if they can't find their core
file.
A new "debug dev bug" expert-mode CLI command was added to test the
feature.
This function calls the ha_dump_backtrace() function with a locally
allocated buffer and sends the output slightly indented to fd #2. It's
meant to be used as an emergency backtrace dump.
The backtrace dumping code was located into the thread dump function
but it looks particularly convenient to be able to call it to produce
a dump in other situations, so let's move it to its own function and
make sure it's called last in the function so that we can benefit from
tail merging to save one entry.
In order to simplify the code and remove annoying ifdefs everywhere,
let's always export my_backtrace() and make it adapt to the situation
and return zero if not supported. A small update in the thread dump
function was needed to make sure we don't use its results if it fails
now.
use `stats_fill_fe_stats` when possible to avoid duplicating code; make
use of field selector to get the needed field only.
this should not introduce any difference of output.
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 remove most of the duplicate
code on prometheuse side for the frontend.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
Another patch in order to try to reconciliate haproxy stats and
prometheus. Here I'm adding a proper start time field in order to make
proper use of uptime field.
That being done we can move the calculation in `fill_info`
Signed-off-by: William Dauchy <wdauchy@gmail.com>
in order to prepare a possible merge of fields between haproxy stats and
prometheus, duplicate 3 fields:
INF_MEMMAX
INF_POOL_ALLOC
INF_POOL_USED
Those were specifically named in MB unit which is not what prometheus
recommends. We therefore used them but changed the unit while doing the
calculation. It created a specific case for that, up to the description.
This patch:
- removes some possible confusion, i.e. using MB field for bytes
- will permit an easier merge of fields such as description
First consequence for now, is that we can remove the calculation on
prometheus side and move it on `fill_info`.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
The MUX_ES_NOTIMPL_ERR exit status is added to allow the multiplexers to
report errors about not implemented features. This will be used by the H1
mux to return 501-not-implemented errors.
Add the support for the 501-not-implemented status code with the
corresponding default message. The documentation is updated accordingly
because it is now part of status codes HAProxy may emit via an errorfile or
a deny/return HTTP action.
When a tcpcheck ruleset uses multiple connections, the existing one must be
closed and destroyed before openning the new one. This part is handled in
the tcpcheck_main() function, when called from the wake callback function
(wake_srv_chk). But it is indeed a problem, because this function may be
called from the mux layer. This means a mux may call the wake callback
function of the data layer, which may release the connection and the mux. It
is easy to see how it is hazardous. And actually, depending on the
scheduling, it leads to crashes.
Thus, we must avoid to release the connection in the wake callback context,
and move this part in the check's process function instead. To do so, we
rely on the CHK_ST_CLOSE_CONN flags. When a connection must be replaced by a
new one, this flag is set on the check, in tcpcheck_main() function, and the
check's task is woken up. Then, the connection is really closed in
process_chk_conn() function.
This patch must be backported as far as 2.2, with some adaptations however
because the code is not exactly the same.
Now the show_fd helpers at the transport and mux levels return an integer
which indicates whether or not the inspected entry looks suspicious. When
an entry is reported as suspicious, "show fd" will suffix it with an
exclamation mark ('!') in the dump, that is supposed to help detecting
them.
For now, helpers were adjusted to adapt to the new API but none of them
reports any suspicious entry yet.
Just like we did for the muxes, now the transport layers will have the
ability to provide helpers to report more detailed information about their
internal context. When the helper is not known, the pointer continues to
be dumped as-is if it's not NULL. This way a transport with no context nor
dump function will not add a useless "xprt_ctx=(nil)" but the pointer will
be emitted if valid or if a helper is defined.
When 0c439d895 ("BUILD: tools: make resolve_sym_name() return a const")
was written, the pointer argument ought to have been turned to const for
more flexibility. Let's do it now.
It's about the third time I get confused by these functions, half of
which manipulate the reference as a whole and those manipulating only
an entry. For me "pat_ref_commit" means committing the pattern reference,
not just an element, so let's rename it. A number of other ones should
really be renamed before 2.4 gets released :-/
This function must be used to emit an alert if a proxy does not have at
least one of the requested capabilities. An additional message may be
appended to the alert.
This is from the output of codespell. It's done at once over a bunch
of files and only affects comments, so there is nothing user-visible.
No backport needed.
commit c55a626217 ("MINOR: contrib/prometheus-exporter: Add
missing global and per-server metrics") is renaming two metrics between
v2.2 and v2.3:
server_idle_connections_current
server_idle_connections_limit
It is breaking some tools which are making use of those metrics while
supporting several haproxy versions. This build_info will permit tools
which make use of metrics to be able to match the haproxy version and
change the list of expected metrics. This was possible using the haproxy
stats socket but not with prometheus export.
This patch follows prometheus best pratices to export specific software
informations. It is adding a new field `build_info` so we can extend it
to other parameters if needed in the future.
example output:
# HELP haproxy_process_build_info HAProxy build info.
# TYPE haproxy_process_build_info gauge
haproxy_process_build_info{version="2.4-dev5-2e1a3f-5"} 1
Even though it is not a bugfix, this patch will make more sense when
backported up to >= 2.0
Signed-off-by: William Dauchy <wdauchy@gmail.com>
This allows using the address of the server rather than the name of the
server for keeping track of servers in a backend for stickiness.
The peers code was also extended to support feeding the dictionary using
this key instead of the name.
Fixes#814
The accept-encoding normalizer now explicitely manages a subset of
encodings which will all have their own bit in the encoding bitmap
stored in the cache entry. This way two requests with the same primary
key will be served the same cache entry if they both explicitely accept
the stored response's encoding, even if their respective secondary keys
are not the same and do not match the stored response's one.
The actual hash of the accept-encoding will still be used if the
response's encoding is unmanaged.
The encoding matching and the encoding weight parsing are done for every
subpart of the accept-encoding values, and a bitmap of accepted
encodings is built for every request. It is then tested upon any stored
response that has the same primary key until one with an accepted
encoding is found.
The specific "identity" and "*" accept-encoding values are managed too.
When storing a response in the key, we also parse the content-encoding
header in order to only set the response's corresponding encoding's bit
in its cache_entry encoding bitmap.
This patch fixes GitHub issue #988.
It does not need to be backported.
If any of the secondary hash normalizing functions raises an error, the
secondary hash will be unusable. In this case, the response will not be
stored anymore.
Add traces to have an idea why this function may fail. In fact
in never fails when the passed parameters are correct, especially the
lengths. This is not the case when a packet is not correctly built
before being encrypted.
Even if the size of frames built by qc_build_frm() are computed so that
not to overflow a buffer, do not rely on this and always makes a packet
build fails if we could not build a frame.
Also add traces to have an idea where qc_build_frm() fails.
Fixes a memory leak in qc_build_phdshk_apkt().
Remove ->ifcdata which was there to control the CRYPTO data sent to the
peer so that not to saturate its reception buffer. This was a sort
of flow control.
Add ->prep_in_flight counter to the QUIC path struct to control the
number of bytes prepared to be sent so that not to saturare the
congestion control window. This counter is increased each time a
packet was built. This has nothing to see with ->in_flight which
is the real in flight number of bytes which have really been sent.
We are olbiged to maintain two such counters to know how many bytes
of data we can prepared before sending them.
Modify traces consequently which were useful to diagnose issues about
the congestion control window usage.
As there is a lot of information in this protocol, this is not
easy to make the traces readable. We remove here a few of them and
shorten some line shortening the variable names.
This patch adds QUIC structs to server struct so that to make the QUIC code
compile. Also initializes the ebtree to store the connections by connection
IDs.
This patch adds a quic_transport_params struct to bind_conf struct
used for the listeners. This is to store the QUIC transport parameters
for the listeners. Also initializes them when calling str2listener().
Before str2sa_range() it's too early to figure we're going to speak QUIC,
and after it's too late as listeners are already created. So it seems that
doing it in str2listener() when the protocol is discovered is the best
place.
Also adds two ebtrees to the underlying receivers to store the connection
by connections IDs (one for the original connection IDs, and another
one for the definitive connection IDs which really identify the connections.
However it doesn't seem normal that it is stored in the receiver nor the
listener. There should be a private context in the listener so that
protocols can store internal information. This element should in
fact be the listener handle.
Something still feels wrong, and probably we'll have to make QUIC and
SSL co-exist: a proof of this is that there's some explicit code in
bind_parse_ssl() to prevent the "ssl" keyword from replacing the xprt.
This patch imports all the definitions for QUIC protocol with few modifications
from 20200720-quic branch of quic-dev repository found at
https://github.com/haproxytech/quic-dev.
QUIC needs to initialize its BIO and SSL session the same way as for SSL over TCP
connections. It needs also to use the same ClientHello callback.
This patch only exports functions and variables shared between QUIC and SSL/TCP
connections.
We add src/quic_sock.c QUIC specific socket management functions as callbacks
for the control layer: ->accept_conn, ->default_iocb and ->rx_listening.
accept_conn() will have to be defined. The default I/O handler only recvfrom()
the datagrams received. Furthermore, ->rx_listening callback always returns 1 at
this time but should returns 0 when reloading the processus.
This is a simple patch to prepare the integration of QUIC support to come.
quic_conn struct is supposed to embed any QUIC specific information for a QUIC
connection.
As QUIC is a connection oriented protocol, this file is almost a copy of
proto_tcp without TCP specific features. To suspend/resume a QUIC receiver
we proceed the same way as for proto_udp receivers.
With the recent updates to the listeners, we don't need a specific set of
quic*_add_listener() functions, the default ones are sufficient. The fields
declaration were reordered to make the various layers more visible like in
other protocols.
udp_suspend_receiver/udp_resume_receiver are up-to-date (the check for INHERITED
is present) and the code being UDP-specific, it's normal to use UDP here.
Note that in the future we might more reasily reference stacked layers so that
there's no more need for specifying the pointer here.
This way we make all xxhash functions inline, with implementations being
directly included within xxhash.h.
Makefile is updated as well, since we don't need to compile and link
xxhash.o anymore.
Inlining should improve performance on small data inputs.
A new XXH3 variant of hash functions shows a noticeable improvement in
performance (especially on small data), and also brings 128-bit support,
better inlining and streaming capabilities.
Performance comparison is available here:
https://github.com/Cyan4973/xxHash/wiki/Performance-comparison
The assembler on MacOS aarch64 interprets ; as the beginning of comments,
so it is not suitable for separating instructions in inline asm. Use \n
instead.
This should be backported to 2.3, 2.2, 2.1, 2.0 and 1.9.
The MAX_DELAY_MS which is set an upper limit to the poll wait time and
force a wakeup this often used to be set to 1 second in order to easily
spot and correct time drifts. This was added 12 years ago at an era
where virtual machines were starting to become common in server
environments while not working particularly well. Nowadays, such issues
are not as common anymore, however forcing 64 threads to wake up every
single second starts to make the process visible on otherwise idle
systems. Let's increase this wakeup interval to one minute. In the worst
case it will make idle threads wake every second, which remains low.
If this is not sufficient anymore on some systems, another approach
would consist in implementing a deep-sleep mode which only triggers
after a while and which is always disabled if any time drift is
observed.
This fixes building hpack from contrib, which failed because of the
undeclared VAR_ARRAY:
make -C contrib/hpack
...
cc -O2 -Wall -g -I../../include -fwrapv -fno-strict-aliasing -c -o gen-enc.o gen-enc.c
In file included from gen-enc.c:18:
../../include/haproxy/hpack-tbl-t.h:105:23: error: 'VAR_ARRAY' undeclared here (not in a function)
105 | struct hpack_dte dte[VAR_ARRAY]; /* dynamic table entries */
...
As discussed in the thread below, let's redefine VAR_ARRAY in this file
so that it remains self-sustaining:
https://www.mail-archive.com/haproxy@formilux.org/msg39212.html
SSL_CTX_get0_privatekey is openssl/boringssl specific function present
since openssl-1.0.2, let us define readable guard for it, not depending
on HA_OPENSSL_VERSION
As Ilya reported in issue #998, gcc 11 complains about misleading code
indentation which is in fact caused by dead assignments to zero after
a loop which stops on zero. Let's clean both of these.
Due to the addition of the OpenTracing filter it is necessary to define
ARGC_OT enum. This value is used in the functions fmt_directive() and
smp_resolve_args().
The OpenTracing filter uses several internal HAProxy functions to work
with variables and therefore requires two static local HAProxy functions,
var_accounting_diff() and var_clear(), to be declared global.
In fact, the var_clear() function was not originally defined as static,
but it lacked a declaration.
SSL_CTX_add_server_custom_ext is openssl specific function present
since openssl-1.0.2, let us define readable guard for it, not depending
on HA_OPENSSL_VERSION
Right now the connection subscribe/unsubscribe code needs to manipulate
FDs, which is not compatible with QUIC. In practice what we need there
is to be able to either subscribe or wake up depending on readiness at
the moment of subscription.
This commit introduces two new functions at the control layer, which are
provided by the socket code, to check for FD readiness or subscribe to it
at the control layer. For now it's not used.
Now we don't touch the fd anymore there, instead we rely on the ->drain()
provided by the control layer. As such the function was renamed to
conn_ctrl_drain().
This is what we need to drain pending incoming data from an connection.
The code was taken from conn_sock_drain() without the connection-specific
stuff. It still takes a connection for now for API simplicity.
conn_fd_handler() is 100% specific to socket code. It's about time
it moves to sock.c which manipulates socket FDs. With it comes
conn_fd_check() which tests for the socket's readiness. The ugly
connection status check at the end of the iocb was moved to an inlined
function in connection.h so that if we need it for other socket layers
it's not too hard to reuse.
The code was really only moved and not changed at all.
The send() loop present in this function and the error handling is already
present in raw_sock_from_buf(). Let's rely on it instead and stop touching
the FD from this place. The send flag was changed to use a more agnostic
CO_SFL_*. The name was changed to "conn_ctrl_send()" to remind that it's
meant to be used to send at the lowest level.
These are two other areas where this fd_stop_recv()/fd_stop_send() makes no
sense anymore. Both happen by definition while the FD is *not* subscribed,
since nowadays it's subscribed after failing recv()/send(), in which case
we cannot close.
These functions used to disable polling for writes when shutting down
but this is no longer used as it still happens later when closing if the
connection was subscribed to FD events. Let's just remove this fake and
undesired dependency on the FD layer.
Add a new http-request action 'set-timeout [server/tunnel]'. This action
can be used to update the server or tunnel timeout of a stream. It takes
two parameters, the timeout name to update and the new timeout value.
This rule is only valid for a proxy with backend capabilities. The
timeout value cannot be null. A sample expression can also be used
instead of a plain value.
Allow the modification of the tunnel timeout on the stream side.
Use a new field in the stream for the tunnel timeout. It is initialized
by the tunnel timeout from backend unless it has already been set by a
set-timeout tunnel rule.
These functions are not used anymore and were quite confusing given that
their names reflected their original role and not the current ones. Let's
kill them before they inspire anyone.
We had cs_close() which forces a CS_SHR_RESET mode on the read side,
and due to this there are a few call places in the checks which
perform a manual call to conn_sock_drain() before calling cs_close().
This is absurd by principle, and it can be counter-productive in the
case of a mux where this could even cause the opposite of the desired
effect by deleting pending frames on the socket before closing.
Let's add cs_drain_and_close() which uses the CS_SHR_DRAIN mode to
prepare this.
QUIC will rely on UDP at the receiver level, and will need these functions
to suspend/resume the receivers. In the future, protocol chaining may
simplify this.
In conn_ctrl_init() and conn_ctrl_close() we now use the control layer's
functions instead of manipulating the FD directly. This is safe since the
control layer is always present when done. Note that now we also adjust
the flag before calling the function to make things cleaner in case such
a layer would need to call the same functions again for any reason.
Currnetly conn_ctrl_init() does an fd_insert() and conn_ctrl_close() does an
fd_delete(). These are the two only short-term obstacles against using a
non-fd handle to set up a connection. Let's have pur these into the protocol
layer, along with the other connection-level stuff so that the generic
connection code uses them instead. This will allow to define new ones for
other protocols (e.g. QUIC).
Since we only support regular sockets at the moment, the code was placed
into sock.c and shared with proto_tcp, proto_uxst and proto_sockpair.
For the sake of an improved readability, let's group the protocol
field members according to where they're supposed to be defined:
- connection layer (note: for now even UDP needs one)
- binding layer
- address family
- socket layer
Nothing else was changed.
The various protocols were made static since there was no point in
exporting them in the past. Nowadays with QUIC relying on UDP we'll
significantly benefit from UDP being exported and more generally from
being able to declare some functions as being the same as other
protocols'.
In an ideal world it should not be these protocols which should be
exported, but the intermediary levels:
- socket layer (sock.c only right now), already exported as functions
but nothing structured at the moment ;
- family layer (sock_inet, sock_unix, sockpair etc): already structured
and exported
- binding layer (the part that relies on the receiver): currently fused
within the protocol
- connectiong layer (the part that manipulates connections): currently
fused within the protocol
- protocol (connection's control): shouldn't need to be exposed
ultimately once the elements above are in an easily sharable way.
This field used to be needed before commit 2b5e0d8b6 ("MEDIUM: proto_udp:
replace last AF_CUST_UDP* with AF_INET*") as it was used as a protocol
entry selector. Since this commit it's always equal to the socket family's
value so it's entirely redundant. Let's remove it now to simplify the
protocol definition a little bit.
The input buffer passed as argument to create a new stream must not be
transferred when the request channel is initialized because the channel
flags are not set at this stage. In addition, the API is a bit confusing
regarding the buffer owner when an error occurred. The caller remains the
owner, but reading the code it is not obvious.
So, first of all, to avoid any ambiguities, comments are added on the
calling chain to make it clear. The buffer owner is the caller if any error
occurred. And the ownership is transferred to the stream on success.
Then, to make things simple, the ownership is transferred at the end of
stream_new(), in case of success. And the input buffer is updated to point
on BUF_NULL. Thus, in all cases, if the caller try to release it calling
b_free() on it, it is not a problem. Of course, it remains the caller
responsibility to release it on error.
The patch fixes a bug introduced by the commit 26256f86e ("MINOR: stream:
Pass an optional input buffer when a stream is created"). No backport is
needed.
With the removal of the family-specific port setting, all protocol had
exactly the same implementation of ->add(). A generic one was created
with the name "default_add_listener" so that all other ones can now be
removed. The API was slightly adjusted so that the protocol and the
listener are passed instead of the listener and the port.
Note that all protocols continue to provide this ->add() method instead
of routinely calling default_add_listener() from create_listeners(). This
makes sure that any non-standard protocol will still be able to intercept
the listener addition if needed.
This could be backported to 2.3 along with the few previous patches on
listners as a pure code cleanup.
At various places we need to set a port on an IPv4 or IPv6 address, and
it requires casts that are easy to get wrong. Let's add a new set_port()
helper to the address family to assist in this. It will be directly
accessible from the protocol and will make the operation seamless.
Right now this is only implemented for sock_inet as other families do
not need a port.
This flags is now unused. It was used in REQ_WAIT_HTTP analyser, when a
stream was waiting for a request, to set the keep-alive timeout or to avoid
to send HTTP errors to client.
The ctl param MUX_EXIT_STATUS can be request to get the exit status of a
multiplexer. For instance, it may be an HTTP status code or an H2 error. For
now, 0 is always returned. When the mux h1 will be able to return HTTP
errors itself, this ctl param will be used to get the HTTP status code from
the logs.
the mux_exit_status enum has been created to map internal mux exist status
to generic one. Thus there is 5 possible status for now: success, invalid
error, timeout error, internal error and unknown.
cumulative numbers of http request and http errors of counters tracked at
the session level and their rates can now be updated at the session level
thanks to two new functions. These functions are not used for now, but it
will be called to keep tracked counters up-to-date if an error occurs before
the stream creation.
The cumulative numbers of http requests, http errors, bytes received and
sent and their respective rates for a tracked counters are now updated using
specific stream independent functions. These functions are used by the
stream but the aim is to allow the session to do so too. For now, there is
no reason to perform these updates from the session, except from the mux-h2
maybe. But, the mux-h1, on the frontend side, will be able to return some
errors to the client, before the stream creation. In this case, it will be
mandatory to update counters tracked at the session level.
It is now possible to set the buffer used by the channel request buffer when
a stream is created. It may be useful if input data are already received,
instead of waiting the first call to the mux rcv_buf() callback. This change
is mandatory to support H1 connection with no stream attached.
For now, the multiplexers don't pass any buffer. BUF_NULL is thus used to
call stream_create_from_cs().
This callback function was only defined by the mux-h1. But it has been
removed in the previous commit because it is unused now. So, we can do a
step forward removing the callback function from the mux definition and the
cs_info structure.
The idle duration between two streams is added to the session structure. It
is not necessarily pertinent on all protocols. In fact, it is only defined
for H1 connections. It is the duration between two H1 transactions. But the
.get_cs_info() callback function on the multiplexers only exists because
this duration is missing at the session level. So it is a simplification
opportunity for a really low cost.
To reduce the cost, a hole in the session structure is filled by moving
.srv_list field at the end of the structure.
The goal is to allow execution of one main lua state per thread.
The array introduces storage of one reference per thread, because each
lua state can have different reference id for a same function. A function
returns the preferred state id according to configuration and current
thread id.
The goal is to allow execution of one main lua state per thread.
"state_from" is a pointer to the parent lua state. "state_id"
is the index of the parent state id in the reference lua states
array. "state_id" is better because the lock is a "== 0" test
which is quick than pointer comparison. In other way, the state_id
index could index other things the the Lua state concerned. I
think to the function references.
The goal is to allow execution of one main lua state per thread.
This function will initialize the struct with other things than 0.
With this function helper, the initialization is centralized and
it prevents mistakes. This patch also keeps a reference to each
declared function in a list. It will be useful in next patches to
control consistency of declared references.
The goal is to allow execution of one main lua state per thread.
The function hlua_ctx_init() now gets the original lua state from
its caller. This allows the initialisation of lua_thread (coroutines)
from any master lua state.
The parent lua state is stored in the hlua struct.
This patch is a temporary transition, it will be modified later.
The goal is to allow execution of one main lua state per thread.
Because this struct will be filled after the configuration parser, we
cannot copy the content. The actual state of the Haproxy code doesn't
justify this change, it is an update preparing next steps.
This function will be useful to check if the keyword is already registered.
Also add a define for the max number of args.
This will be needed by a next patch to fix a bug and will have to be
backported.
This function simply calls action_lookup() on the private service_keywords,
to look up a service name. This will be used to detect double registration
of a same service from Lua.
This will be needed by a next patch to fix a bug and will have to be
backported.
These functions will be useful to check if a keyword is already registered.
This will be needed by a next patch to fix a bug, and will need to be
backported.
Sometimes it would be nice to be able to only trace abnormal events such
as protocol errors. Let's add a new "error" level below the "user" level
for this. This will allow to add TRACE_ERROR() at various error points
and only see them.
This patch adds a new logging variable '%HPO' for logging HTTP path only
(without query string) from relative or absolute URI.
For example:
log-format "hpo=%HPO hp=%HP hu=%HU hq=%HQ"
GET /r/1 HTTP/1.1
=>
hpo=/r/1 hp=/r/1 hu=/r/1 hq=
GET /r/2?q=2 HTTP/1.1
=>
hpo=/r/2 hp=/r/2 hu=/r/2?q=2 hq=?q=2
GET http://host/r/3 HTTP/1.1
=>
hpo=/r/3 hp=http://host/r/3 hu=http://host/r/3 hq=
GET http://host/r/4?q=4 HTTP/1.1
=>
hpo=/r/4 hp=http://host/r/4 hu=http://host/r/4?q=4 hq=?q=4
Since 2.3 default local log format always adds hostame field.
This behavior change was due to log/sink re-work, because according
to rfc3164 the hostname field is mandatory.
This patch re-introduce a legacy "local" format which is analog
to rfc3164 but with hostname stripped. This is the new
default if logs are generated by haproxy.
To stay compliant with previous configurations, the option
"log-send-hostname" acts as if the default format is switched
to rfc3164.
This patch addresses the github issue #963
This patch should be backported in branches >= 2.3.
In issue #958 Ashley Penney reported intermittent crashes on AWS's ARM
nodes which would not happen on x86 nodes. After investigation it turned
out that the Neoverse N1 CPU cores used in the Graviton2 CPU are much
more aggressive than the usual Cortex A53/A72/A55 or any x86 regarding
memory ordering.
The issue that was triggered there is that if a tasklet_wakeup() call
is made on a tasklet scheduled to run on a foreign thread and that
tasklet is just being dequeued to be processed, there can be a race at
two places:
- if MT_LIST_TRY_ADDQ() happens between MT_LIST_BEHEAD() and
LIST_SPLICE_END_DETACHED() if the tasklet is alone in the list,
because the emptiness tests matches ;
- if MT_LIST_TRY_ADDQ() happens during LIST_DEL_INIT() in
run_tasks_from_lists(), then depending on how LIST_DEL_INIT() ends
up being implemented, it may even corrupt the adjacent nodes while
they're being reused for the in-tree storage.
This issue was introduced in 2.2 when support for waking up remote
tasklets was added. Initially the attachment of a tasklet to a list
was enough to know its status and this used to be stable information.
Now it's not sufficient to rely on this anymore, thus we need to use
a different information.
This patch solves this by adding a new task flag, TASK_IN_LIST, which
is atomically set before attaching a tasklet to a list, and is only
removed after the tasklet is detached from a list. It is checked
by tasklet_wakeup_on() so that it may only be done while the tasklet
is out of any list, and is cleared during the state switch when calling
the tasklet. Note that the flag is not set for pure tasks as it's not
needed.
However this introduces a new special case: the function
tasklet_remove_from_tasklet_list() needs to keep both states in sync
and cannot check both the state and the attachment to a list at the
same time. This function is already limited to being used by the thread
owning the tasklet, so in this case the test remains reliable. However,
just like its predecessors, this function is wrong by design and it
should probably be replaced with a stricter one, a lazy one, or be
totally removed (it's only used in checks to avoid calling a possibly
scheduled event, and when freeing a tasklet). Regardless, for now the
function exists so the flag is removed only if the deletion could be
done, which covers all cases we're interested in regarding the insertion.
This removal is safe against a concurrent tasklet_wakeup_on() since
MT_LIST_DEL() guarantees the atomic test, and will ultimately clear
the flag only if the task could be deleted, so the flag will always
reflect the last state.
This should be carefully be backported as far as 2.2 after some
observation period. This patch depends on previous patch
"MINOR: task: remove __tasklet_remove_from_tasklet_list()".
This function is only used at a single place directly within the
scheduler in run_tasks_from_lists() and it really ought not be called
by anything else, regardless of what its comment says. Let's delete
it, move the two lines directly into the call place, and take this
opportunity to factor the atomic decrement on tasks_run_queue. A comment
was added on the remaining one tasklet_remove_from_tasklet_list() to
mention the risks in using it.
This function is only called at a single place and adds more confusion
than it removes. It also makes one think it could be used outside of
the scheduler while it must absolutely not. Let's just move its two
lines to the call place, making the code more readable there. In
addition this clearly shows that the preliminary LIST_INIT() is
useless since the entry is immediately overwritten.
In MT_LIST_TRY_ADDQ() and MT_LIST_TRY_ADD() we can't just check if the
element is already in a list, because there's a small race condition, it
could be added between the time we checked, and the time we actually set
its next and prev, so we have to lock it first.
This is required to address issue #958.
This should be backported to 2.3, 2.2 and 2.1.
As suggested by @AGSaidi in issue #958, on ARMv8 its convenient to use
an "isb" instruction in pl_cpu_relax() to improve fairness. Without it
I've met a few watchdog conditions on valid locks with 16 threads,
indicating that some threads couldn't manage to get it in 2 seconds. I
never happened again with it. In addition, the performance increased
by slightly more than 5% thanks to the reduced contention.
This should be backported as far as 2.2, possibly even 2.0.
The parsing of the check options based on tcp-check rules (redis, spop,
smtp, http...) are moved aways from check.c. Now, these functions are placed
in tcpcheck.c. These functions are only related to the tcpcheck ruleset
configured on a proxy and not to the health-check attached to a server.
This option is now ignored because I/O check buffers are now allocated using the
buffer pool. Thus, it is marked as deprecated in the documentation and ignored
during the configuration parsing. The field is also removed from the global
structure.
Because this option is ignored since a recent fix, backported as fare as 2.2,
this patch should be backported too. Especially because it updates the
documentation.
Historically, the input and output buffers of a check are allocated by hand
during the startup, with a specific size (not necessarily the same than
other buffers). But since the recent refactoring of the checks to rely
exclusively on the tcp-checks and to use the underlying mux layer, this part
is totally buggy. Indeed, because these buffers are now passed to a mux,
they maybe be swapped if a zero-copy is possible. In fact, for now it is
only possible in h2_rcv_buf(). Thus the bug concretely only exists if a h2
health-check is performed. But, it is a latent bug for other muxes.
Another problem is the size of these buffers. because it may differ for the
other buffer size, it might be source of bugs.
Finally, for configurations with hundreds of thousands of servers, having 2
buffers per check always allocated may be an issue.
To fix the bug, we now allocate these buffers when required using the buffer
pool. Thus not-running checks don't waste memory and muxes may swap them if
possible. The only drawback is the check buffers have now always the same
size than buffers used by the streams. This deprecates indirectly the
"tune.chksize" global option.
In addition, the http-check regtest have been update to perform some h2
health-checks.
Many thanks to @VigneshSP94 for its help on this bug.
This patch should solve the issue #936. It relies on the commit "MINOR:
tcpcheck: Don't handle anymore in-progress send rules in tcpcheck_main".
Both must be backport as far as 2.2.
bla
The Vary functionality is based on a secondary key that needs to be
calculated for every request to which a server answers with a Vary
header. The Vary header, which can only be found in server responses,
determines which headers of the request need to be taken into account in
the secondary key. Since we do not want to have to store all the headers
of the request until we have the response, we will pre-calculate as many
sub-hashes as there are headers that we want to manage in a Vary
context. We will only focus on a subset of headers which are likely to
be mentioned in a Vary response (accept-encoding and referer for now).
Every managed header will have its own normalization function which is
in charge of transforming the header value into a core representation,
more robust to insignificant changes that could exist between multiple
clients. For instance, two accept-encoding values mentioning the same
encodings but in different orders should give the same hash.
This patch adds a function that parses a Vary header value and checks if
all the values belong to our supported subset. It also adds the
normalization functions for our two headers, as well as utility
functions that can prebuild a secondary key for a given request and
transform it into an actual secondary key after the vary signature is
determined from the response.
When at least one data filter is registered on a channel, the offsets of all
filters must be kept up to date. For data filters but also for others. It is
safer to do it in that way. Indirectly, this patch fixes 2 hidden bugs
revealed by the commit 22fca1f2c ("BUG/MEDIUM: filters: Forward all filtered
data at the end of http filtering").
The first one, the worst of both, happens at the end of http filtering when
at least one data filtered is registered on the channel. We call the
http_end() callback function on the filters, when defined, to finish the
http filtering. But it is performed for all filters. Before the commit
22fca1f2c, the only risk was to call the http_end() callback function
unexpectedly on a filter. Now, we may have an overflow on the offset
variable, used at the end to forward all filtered data. Of course, from the
moment we forward an arbitrary huge amount of data, all kinds of bad things
may happen. So offset computation is performed for all filters and
http_end() callback function is called only for data filters.
The other one happens when a data filter alter the data of a channel, it
must update the offsets of all previous filters. But the offset of non-data
filters must be up to date, otherwise, here too we may have an integer
overflow.
Another way to fix these bugs is to always ignore non-data filters from the
offsets computation. But this patch is safer and probably easier to
maintain.
This patch must be backported in all versions where the above commit is. So
as far as 2.0.
