During the stick-table teaching process which occurs at reloading/restart time,
expiration dates of stick-tables entries were not synchronized between peers.
This patch adds two new stick-table messages to provide such a synchronization feature.
As these new messages are not supported by older haproxy peers protocol versions,
this patch increments peers protol version, from 2.0 to 2.1, to help in detecting/supporting
such older peers protocol implementations so that new versions might still be able
to transparently communicate with a newer one.
[wt: technically speaking it would be nice to have this backported into 1.6
as some people who reload often are affected by this design limitation, but
it's not a totally transparent change that may make certain users feel
reluctant to upgrade older versions. Let's let it cook in 1.7 first and
decide later]
The binary sample to stick-table key conversion is wrong. It doesn't
check that the binary sample is writable before padding it. After a
quick audit, it doesn't look like any existing sample fetch function
can trigger this bug. The correct fix consists in calling smp_make_rw()
prior to padding the sample.
This fix should be backported to 1.6.
When a stick-table key is derived from a string-based sample, it checks
if it's properly zero-terminated otherwise tries to do so. But the test
doesn't work for two reasons :
- the reported allocated size may be zero while the sample is maked as
not CONST (eg: certain sample fetch functions like smp_fetch_base()
do this), so smp_dup() prior to the recent changes will fail on this.
- the string might have been converted from a binary sample, where the
trailing zero is not appended. If the sample was writable, smp_dup()
would not modify it either and we would fail again here. This may
happen with req.payload or req.body_param for example.
The correct solution consists in calling smp_make_safe() to ensure the
sample is usable as a valid string.
This fix must be backported to 1.6.
The stick-table converters used to take a string on input because it
was the only type that could be casted to from any other type. This is
inefficient and possibly inaccurate sometimes. For example in order to
look up an IP address, it must first be converted to a string then
converted back to an IP address.
We've had SMP_T_ANY introduced long ago in 1.6, but unfortunately it
was not propagated to these converters, so let's do it now.
It's important to note that a few direct type conversions which already
would not make any sense are not possible (for example, converting a
boolean to an IP address or an HTTP method to an integer). While this
would have caused the lookup to be performed on the wrong key, now the
lookup will fail and the converter will return no data. While there
should not be any case where this happens, it's probably best to avoid
backporting this change before a longer observation period.
Baptiste reported that the table_conn_rate() converter would always
return zero in 1.6.5. In fact, commit bc8c404 ("MAJOR: stick-tables:
use sample types in place of dedicated types") broke all stick-table
converters because smp_to_stkey() now returns a pointer to the sample
instead of holding a copy of the key, and the converters used to
reinitialize the sample prior to performing the lookup. Only
"in_table()" continued to work.
The construct is still fragile, so some comments were added to a few
function to clarify their impacts. It's also worth noting that there
is no point anymore in forcing these converters to take a string on
input, but that will be changed in another commit.
The bug was introduced in 1.6-dev4, this fix must be backported to 1.6.
In C89, "void *" is automatically promoted to any pointer type. Casting
the result of malloc/calloc to the type of the LHS variable is therefore
unneeded.
Most of this patch was built using this Coccinelle patch:
@@
type T;
@@
- (T *)
(\(lua_touserdata\|malloc\|calloc\|SSL_get_app_data\|hlua_checkudata\|lua_newuserdata\)(...))
@@
type T;
T *x;
void *data;
@@
x =
- (T *)
data
@@
type T;
T *x;
T *data;
@@
x =
- (T *)
data
Unfortunately, either Coccinelle or I is too limited to detect situation
where a complex RHS expression is of type "void *" and therefore casting
is not needed. Those cases were manually examined and corrected.
These two actions don't touch the table so the entry will expire and
the values will not be pushed to other peers. Also in the case of gpc0,
the gpc0_rate counter must be updated. The issue was reported by
Ruoshan Huang.
This fix needs to be backported to 1.6.
Since commit bc4c1ac ("MEDIUM: http/tcp: permit to resume http and tcp
custom actions"), some actions may yield and be called back when new
information are available. Unfortunately some of them may continue to
yield because they simply don't know that it's the last call from the
rule set. For this reason we'll need to pass a flag to the custom
action to pass such information and possibly other at the same time.
If an entry is still not present in the update tree, we could miss to schedule
for a push depending of an un-initialized value (upd.key remains un-initialized
for new sessions or isn't re-initalized for reused ones).
In the same way, if an entry is present in the tree, but its update's tick
is far in the past (> 2^31). We could consider it's still scheduled even if
it is not the case.
The fix consist to force the re-scheduling of an update if it was not present in
the updates tree or if the update is not in the scheduling window of every peers.
Before this patch, two type of custom actions exists: ACT_ACTION_CONT and
ACT_ACTION_STOP. ACT_ACTION_CONT is a non terminal action and ACT_ACTION_STOP is
a terminal action.
Note that ACT_ACTION_STOP is not used in HAProxy.
This patch remove this behavior. Only type type of custom action exists, and it
is called ACT_CUSTOM. Now, the custion action can return a code indicating the
required behavior. ACT_RET_CONT wants that HAProxy continue the current rule
list evaluation, and ACT_RET_STOP wants that HAPRoxy stops the the current rule
list evaluation.
This patch removes the special stick tables types names and
use the standard sample type names. This avoid the maintainance
of two types and remove the switch/case for matching a sample
type for each stick table type.
This patch is the first step for sample integration. Actually
the stick tables uses her own data type, and some converters
must be called to convert sample type to stick-tables types.
This patch removes the stick-table types and replace it by
the sample types. This prevent:
- Maintenance of two types of converters
- reduce the code using the samples converters
This patch is the first of a serie which merge all the action structs. The
function "tcp-request content", "tcp-response-content", "http-request" and
"http-response" have the same values and the same process for some defined
actions, but the struct and the prototype of the declared function are
different.
This patch try to unify all of these entries.
The union name "data" is a little bit heavy while we read the source
code because we can read "data.data.sint". The rename from "data" to "u"
makes the read easiest like "data.u.sint".
This patch remove the struct information stored both in the struct
sample_data and in the striuct sample. Now, only thestruct sample_data
contains data, and the struct sample use the struct sample_data for storing
his own data.
This patch removes the 32 bits unsigned integer and the 32 bit signed
integer. It replaces these types by a unique type 64 bit signed.
This makes easy the usage of integer and clarify signed and unsigned use.
With the previous version, signed and unsigned are used ones in place of
others, and sometimes the converter loose the sign. For example, divisions
are processed with "unsigned", if one entry is negative, the result is
wrong.
Note that the integer pattern matching and dotted version pattern matching
are already working with signed 64 bits integer values.
There is one user-visible change : the "uint()" and "sint()" sample fetch
functions which used to return a constant integer have been replaced with
a new more natural, unified "int()" function. These functions were only
introduced in the latest 1.6-dev2 so there's no impact on regular
deployments.
This regression was introduce by commit
9c627e84b2 (MEDIUM: sample: Add type any)
New sample type 'any' was not handled in the matrix used to cast
to stick-tables types.
This patch removes the structs "session", "stream" and "proxy" from
the sample-fetches and converters function prototypes.
This permits to remove some weight in the prototype call.
Many such function need a session, and till now they used to dereference
the stream. Once we remove the stream from the embryonic session, this
will not be possible anymore.
So as of now, sample fetch functions will be called with this :
- sess = NULL, strm = NULL : never
- sess = valid, strm = NULL : tcp-req connection
- sess = valid, strm = valid, strm->txn = NULL : tcp-req content
- sess = valid, strm = valid, strm->txn = valid : http-req / http-res
All of them can now retrieve the HTTP transaction *if it exists* from
the stream and be sure to get NULL there when called with an embryonic
session.
The patch is a bit large because many locations were touched (all fetch
functions had to have their prototype adjusted). The opportunity was
taken to also uniformize the call names (the stream is now always "strm"
instead of "l4") and to fix indent where it was broken. This way when
we later introduce the session here there will be less confusion.
With HTTP/2, we'll have to support multiplexed streams. A stream is in
fact the largest part of what we currently call a session, it has buffers,
logs, etc.
In order to catch any error, this commit removes any reference to the
struct session and tries to rename most "session" occurrences in function
names to "stream" and "sess" to "strm" when that's related to a session.
The files stream.{c,h} were added and session.{c,h} removed.
The session will be reintroduced later and a few parts of the stream
will progressively be moved overthere. It will more or less contain
only what we need in an embryonic session.
Sample fetch functions and converters will have to change a bit so
that they'll use an L5 (session) instead of what's currently called
"L4" which is in fact L6 for now.
Once all changes are completed, we should see approximately this :
L7 - http_txn
L6 - stream
L5 - session
L4 - connection | applet
There will be at most one http_txn per stream, and a same session will
possibly be referenced by multiple streams. A connection will point to
a session and to a stream. The session will hold all the information
we need to keep even when we don't yet have a stream.
Some more cleanup is needed because some code was already far from
being clean. The server queue management still refers to sessions at
many places while comments talk about connections. This will have to
be cleaned up once we have a server-side connection pool manager.
Stream flags "SN_*" still need to be renamed, it doesn't seem like
any of them will need to move to the session.
Some usages of the converters need to know the attached session. The Lua
needs the session for retrieving his running context. This patch adds
the "session" as an argument of the converters prototype.
As a consequence of various recent changes on the sample conversion,
a corner case has emerged where it is possible to wait forever for a
sample in track-sc*.
The issue is caused by the fact that functions relying on sample_process()
don't all exactly work the same regarding the SMP_F_MAY_CHANGE flag and
the output result. Here it was possible to wait forever for an output
sample from stktable_fetch_key() without checking the SMP_OPT_FINAL flag.
As a result, if the client connects and closes without sending the data
and haproxy expects a sample which is capable of coming, it will ignore
this impossible case and will continue to wait.
This change adds control for SMP_OPT_FINAL before waiting for extra data.
The various relevant functions have been better documented regarding their
output values.
This fix must be backported to 1.5 since it appeared there.
IP addresses are a perfect example of fixed size data which we could
cast to binary, still it was not allowed by lack of cast function,
eventhough the opposite was allowed in ACLs. Make that possible both
in sample expressions and in stick tables.
Some users want to add their own data types to stick tables. We don't
want to use a linked list here for performance reasons, so we need to
continue to use an indexed array. This patch allows one to reserve a
compile-time-defined number of extra data types by setting the new
macro STKTABLE_EXTRA_DATA_TYPES to anything greater than zero, keeping
in mind that anything larger will slightly inflate the memory consumed
by stick tables (not per entry though).
Then calling stktable_register_data_store() with the new keyword will
either register a new keyword or fail if the desired entry was already
taken or the keyword already registered.
Note that this patch does not dictate how the data will be used, it only
offers the possibility to create new keywords and have an index to
reference them in the config and in the tables. The caller will not be
able to use stktable_data_cast() and will have to explicitly cast the
stable pointers to the expected types. It can be used for experimentation
as well.
These new converters make it possible to look up any sample expression
in a table, and check whether an equivalent key exists or not, and if it
exists, to retrieve the associated data (eg: gpc0, request rate, etc...).
Till now it was only possible using tracking, but sometimes tracking is
not suited to only retrieving such counters, either because it's done too
early or because too many items need to be checked without necessarily
being tracked.
These converters all take a string on input, and then convert it again to
the table's type. This means that if an input sample is of type IPv4 and
the table is of type IP, it will first be converted to a string, then back
to an IP address. This is a limitation of the current design which does not
allow converters to declare that "any" type is supported on input. Since
strings are the only types which can be cast to any other one, this method
always works.
The following converters were added :
in_table, table_bytes_in_rate, table_bytes_out_rate, table_conn_cnt,
table_conn_cur, table_conn_rate, table_gpc0, table_gpc0_rate,
table_http_err_cnt, table_http_err_rate, table_http_req_cnt,
table_http_req_rate, table_kbytes_in, table_kbytes_out,
table_server_id, table_sess_cnt, table_sess_rate, table_trackers.
Currently we have stktable_fetch_key() which fetches a sample according
to an expression and returns a stick table key, but we also need a function
which does only the second half of it from a known sample. So let's cut the
function in two and introduce smp_to_stkey() to perform this lookup. The
first function was adapted to make use of it in order to avoid code
duplication.
stktable_fetch_key() does not indicate whether it returns NULL because
the input sample was not found or because it's unstable. It causes trouble
with track-sc* rules. Just like with sample_fetch_string(), we want it to
be able to give more information to the caller about what it found. Thus,
now we use the pointer to a sample passed by the caller, and fill it with
the information we have about the sample. That way, even if we return NULL,
the caller has the ability to check whether a sample was found and if it is
still changing or not.
The operations applied on types SMP_T_CSTR and SMP_T_STR are the same,
but the check code and the declarations are double, because it must
declare action for SMP_T_C* and SMP_T_*. The declared actions and checks
are the same. this complexify the code. Only the "conv" functions can
change from "C*" to "*"
Now, if a function needs to modify input string, it can call the new
function smp_dup(). This one duplicate data in a trash buffer.
Since commit 348971e (MEDIUM: acl: use the fetch syntax
'fetch(args),conv(),conv()' into the ACL keyword), ACLs wait on input
that may change. This is visible in the configuration below :
tcp-request inspect-delay 3s
tcp-request content accept if REQ_CONTENT
Nothing will pass before the end of the timer. This is because
historically, sample_process() was dedicated to stick tables where
it was absolutely necessary to wait for a stable sample. Now samples
are used by many other things and we can't afford this. So let's move
this check to the stick tables after the call to sample_process()
instead.
This is post-1.5-dev19 work, no backport is required.
This patch allows each sample cast function to specify the sample
output type. The goal is to be able to emit an output type IPv4 or
IPv6 depending on what is found in the input if the next converter
is able to process them both.
The patch also adds a new pseudo type called "ADDR". This type is an
alias for IPV4 and IPV6 which is only used as an input type by converters
who want to express their compatibility with both address formats. It may
not be emitted.
The goal is to unify as much as possible the processing of IPv4 and IPv6
in order not to add extra keywords for the maps which act as converters,
but will match samples like ACLs do with their patterns.
Make the stick-table key converter automatically adapt to the address
family of the input sample. Samples such as "src" will return an address
with a sample type depending on the input family. We'll have to support
such combinations when we add support for maps because the output type
will not necessarily be fixed.
When a process with large stick tables is replaced by a new one and remains
present until the last connection finishes, it keeps these data in memory
for nothing since they will never be used anymore by incoming connections,
except during syncing with the new process. This is especially problematic
when dealing with long session protocols such as WebSocket as it becomes
possible to stack many processes and eat a lot of memory.
So the idea here is to know if a table still needs to be synced or not,
and to purge all unused entries once the sync is complete. This means that
after a few hundred milliseconds when everything has been synchronized with
the new process, only a few entries will remain allocated (only the ones
held by sessions during the restart) and all the remaining memory will be
freed.
Note that we carefully do that only after the grace period is expired so as
not to impact a possible proxy that needs to accept a few more connections
before leaving.
Doing this required to add a sync counter to the stick tables, to know how
many peer sync sessions are still in progress in order not to flush the entries
until all synchronizations are completed.
Commit 07115412 (MEDIUM: stick-table: allocate the table key...) broke
conversion of samples to strings for stick tables, because if replaced
char buf[BUFSIZE] with char buf[0] and the string converters use sizeof
on this part. Note that sizeof was wrong as well but at least it used
to work.
Fix this by making use of the len parameter instead of sizeof.
Keys are copied from samples to stick_table_key. If a key is larger
than the stick_table_key, we have an overflow. In pratice it does not
happen because it requires :
1) a configuration with tune.bufsize larger than BUFSIZE (common)
2) a stick-table configured with keys strictly larger than buffers
3) extraction of data larger than BUFSIZE (eg: using payload())
Points 2 and 3 don't make any sense for a real world configuration. That
said the issue needs be fixed. The solution consists in allocating it the
same size as the global buffer size, just like the samples. This fixes the
issue.
