(http|tcp)-(request|response) action cannot take arguments from the
configuration file. Arguments are useful for executing the action with
a special context.
This patch adds the possibility of passing arguments to an action. It
runs exactly like sample fetches and other Lua wrappers.
Note that this patch implements a 'TODO'.
There's no more reason to keep tcp rules processing inside proto_tcp.c
given that there is nothing in common there except these 3 letters : tcp.
The tcp rules are in fact connection, session and content processing rules.
Let's move them to "tcp-rules" and let them live their life there.
proto/dumpstats.h has been split in 4 files:
* proto/cli.h contains protypes for the CLI
* proto/stats.h contains prototypes for the stats
* types/cli.h contains definition for the CLI
* types/stats.h contains definition for the stats
When:
- A Lua action return data and close the channel. The request status
is set to HTTP_MSG_CLOSED for the request and HTTP_MSG_DONE for the
response.
- HAProxy sets the state HTTP_MSG_ERROR. I don't known why, because
there are many line which sets this state.
- A Lua sample-fetch is executed, typically for building the log
line.
- When the Lua sample fetch exits, a control of the data is
executed. If HAProxy is currently parsing the request, the request
is aborted in order to prevent a segfault or sending corrupted
data.
This ast control is executed comparing the state HTTP_MSG_BODY. When
this state is reached, the request is parsed and no error are
possible. When the state is < than HTTP_MSG_BODY, the parser is
running.
Unfortunately, the code HTTP_MSG_ERROR is just < HTTP_MSG_BODY. When
we are in error, we want to terminate the execution of Lua without
error.
This patch changes the comparaison level.
This patch must be backported in 1.6
It does the opposite of 'set-var' action/converter. It is really useful for
per-process variables. But, it can be used for any scope.
The lua function 'unset_var' has also been added.
Somme HTTP manipulation functions are executed without valid and parsed
requests or responses. This causes a segmentation fault when the executed
code tries to change an empty buffer.
This patch must be backported in the 1.6 version
If an action wrapper stops the processing of the transaction
with a txn_done() function, the return code of the action is
"continue". So the continue can implies the processing of other
like adding headers. However, the HTTP content is flushed and
a segfault occurs.
This patchs add a flag indicating that the Lua code want to
stop the processing, ths flags is forwarded to the haproxy core,
and other actions are ignored.
Must be backported in 1.6
The function txn_done() ends a transaction. It does not make
sense to call this function from a lua sample-fetch wrapper,
because the role of a sample-fetch is not to terminate a
transaction.
This patch modify the role of the fucntion txn_done() if it
is called from a sample-fetch wrapper, now it just ends the
execution of the Lua code like the done() function.
Must be backported in 1.6
The number of arguments pushed in the stack are false, so we try to execute a
function out of the stack. This function is always a nil pointer, so the
following message is displayed.
Lua converter 'testconv': runtime error: attempt to call a nil value.
Thanks Michael Ezzell for the repporting.
This patch must be backported in the 1.6 version.
When compiled with GCC 6, the IP address specified for a frontend was
ignored and HAProxy was listening on all addresses instead. This is
caused by an incomplete copy of a "struct sockaddr_storage".
With the GNU Libc, "struct sockaddr_storage" is defined as this:
struct sockaddr_storage
{
sa_family_t ss_family;
unsigned long int __ss_align;
char __ss_padding[(128 - (2 * sizeof (unsigned long int)))];
};
Doing an aggregate copy (ss1 = ss2) is different than using memcpy():
only members of the aggregate have to be copied. Notably, padding can be
or not be copied. In GCC 6, some optimizations use this fact and if a
"struct sockaddr_storage" contains a "struct sockaddr_in", the port and
the address are part of the padding (between sa_family and __ss_align)
and can be not copied over.
Therefore, we replace any aggregate copy by a memcpy(). There is another
place using the same pattern. We also fix a function receiving a "struct
sockaddr_storage" by copy instead of by reference. Since it only needs a
read-only copy, the function is converted to request a reference.
When a converter or sample is called from within a Lua code, there is a risk
of invalid argument string data usage when the upper boundary is reached.
Would be kind to port to 1.6 if possible.
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.
This patch adds a Lua post initialisation wrapper. It already exists for
pure Lua function, now it executes also C. It is useful for doing things
when the configuration is ready to use. For example we can can browse and
register all the proxies.
All the HAProxy Lua object are declared with the same pattern:
- Add the function __tosting which dumps the object name
- Register the name in the Lua REGISTRY
- Register the reference ID
These action are refactored in on function. This remove some
lines of code.
The functions
- hlua_class_const_int()
- hlua_class_const_str()
- hlua_class_function()
are use for common class registration actions.
The function 'hlua_dump_object()' is generic dump name function.
These functions can be used by all the HAProxy objects, so I move
it into the safe functions file.
This is the continuation of previous patch called "BUG/MAJOR: samples:
check smp->strm before using it".
It happens that variables may have a session-wide scope, and that their
session is retrieved by dereferencing the stream. But nothing prevents them
from being used from a streamless context such as tcp-request connection,
thus crashing the process. Example :
tcp-request connection accept if { src,set-var(sess.foo) -m found }
In order to fix this, we have to always ensure that variable manipulation
only happens via the sample, which contains the correct owner and context,
and that we never use one from a different source. This results in quite a
large change since a lot of functions are inderctly involved in the call
chain, but the change is easy to follow.
This fix must be backported to 1.6, and requires the last two patches.
Some functions like sample_conv_var2smp(), var_get_byname(), and
var_set_byname() directly or indirectly need to access the current
stream and/or session and must find it in the sample itself and not
as a distinct argument. Thus we first need to call smp_set_owner()
prior to each such calls.
Since commit 6879ad3 ("MEDIUM: sample: fill the struct sample with the
session, proxy and stream pointers") merged in 1.6-dev2, the sample
contains the pointer to the stream and sample fetch functions as well
as converters use it heavily. This requires from a lot of call places
to initialize 4 fields, and it was even forgotten at a few places.
This patch provides a convenient helper to initialize all these fields
at once, making it easy to prepare a new sample from a previous one for
example.
A few call places were cleaned up to make use of it. It will be needed
by further fixes.
At one place in the Lua code, it was moved earlier because we used to
call sample casts with a non completely initialized sample, which is
not clean eventhough at the moment there are no consequences.
Since commit 6879ad3 ("MEDIUM: sample: fill the struct sample with the
session, proxy and stream pointers") merged in 1.6-dev2, the sample
contains the pointer to the stream and sample fetch functions as well
as converters use it heavily.
The problem is that earlier commit 87b0966 ("REORG/MAJOR: session:
rename the "session" entity to "stream"") had split the session and
stream resulting in the possibility for smp->strm to be NULL before
the stream was initialized. This is what happens in tcp-request
connection rulesets, as discovered by Baptiste.
The sample fetch functions must now check that smp->strm is valid
before using it. An alternative could consist in using a dummy stream
with nothing in it to avoid some checks but it would only result in
deferring them to the next step anyway, and making it harder to detect
that a stream is valid or the dummy one.
There is still an issue with variables which requires a complete
independant fix. They use strm->sess to find the session with strm
possibly NULL and passed as an argument. All call places indirectly
use smp->strm to build strm. So the problem is there but the API needs
to be changed to remove this duplicate argument that makes it much
harder to know what pointer to use.
This fix must be backported to 1.6, as well as the next one fixing
variables.
A value is copied two time in teh stack, but only one is usefull. The
second copy leaves unused in the stack and take some room for noting.
This path removes the second copy.
Must be backported in 1.6
This patch must be backported in 1.6
hlua_yield() function returns the required sleep time. The Lua core must
be resume the execution after the required time. The core dedicated to
the http and tcp applet doesn't implement the wake up function. It is a
miss.
This patch fix this.
This patch moves the function hlua_checkudata which check that
an object contains the expected class_reference as metatable.
This function is commonly used by all the lua functions.
The function hlua_metatype is also moved.
When Lua executes functions from its API, these can throws an error.
These function must be executed in a special environment which catch
these error, otherwise a critical error (like segfault) can raise.
This patch add a c file called "hlua_fcn.c" which collect all the
Lua/c function needing safe environment for its execution.
The applet can't have access to the session private data. This patch
fix this problem. Now an applet can use private data stored by actions
and fecthes.
INNER and XFERBODY analyzer were set in order to support HTTP applets
from TCP rulesets, but this does not work (cf previous patch).
Other cases already provides theses analyzers, so their addition is
not needed. Furthermore if INNER was set it could cause some headers
to be rewritten (ex: connection) after headers were already forwarded,
resulting in a crash in buffer_insert_line2().
Special thanks to Bernd Helm for providing very detailed information,
captures and stack traces making it possible to spot the root cause
here.
This fix must be backported to 1.6.
HTTP applets request requires everything initilized by
"http_process_request" (analyzer flag AN_REQ_HTTP_INNER).
The applet will be immediately initilized, but its before
the call of this analyzer.
Due to this problem HTTP applets could be called with uncompletely
initialized http_txn.
This fix must be backported to 1.6.
In certain circumstances (eg: Lua HTTP applet called from a
TCP ruleset before http_process_request()), the HTTP TXN is not
yet fully initialized so some information it contains cannot be
relied on. Such information include the HTTP version, the state
of the expect: 100-continue header, the connection header and
the transfer-encoding header.
Here the bug only turns something which already doesn't work
into something wrong, but better avoid any references to the
http_txn from the Lua code to avoid future mistakes.
This patch should be backported into 1.6 for code consistency.
If a sample fetch needing http_txn is called from an HTTP Lua applet,
the result will be invalid and may even cause a crash because some HTTP
data can be forwarded and the HTTP txn is no longer valid.
Here the solution is to ensure that a fetch called from Lua never
needs http_txn. This is done thanks to a new flag HLUA_F_MAY_USE_HTTP
which indicates whether or not it is safe to call a fetch which needs
HTTP.
This fix needs to be backported to 1.6.
This patch converts a boolean "int" to a bitfiled. The main
reason is to save space in the struct if another flag may will
be require.
Note that this patch is required for next fix and will need to be
backported to 1.6.
When a POST is processed by a Lua service, the HTTP header are
potentially gone. So, we cannot retrieve their content using
the standard "hdr" sample fetchs (which will soon become invalid
anyway) from an applet.
This patch add an entry "headers" to the object applet_http. This
entry is an array containing all the headers. It permits to use the
HTTP headers during the processing of the service.
Many thanks to Jan Bruder for reporting this issue with enough
details to reproduce it.
This patch will have to be backported to 1.6 since it will be the
only way to access headers from Lua applets.
Sander Klein reported an error messages about SSLv3 not
being supported on Debian 8, although he didn't force-sslv3.
Vincent Bernat tracked this down to the LUA initialization, which
actually does force-sslv3.
This patch removes force-sslv3 from the LUA initialization, so
the LUA SSL socket can actually use TLS and doesn't trigger
warnings when SSLv3 is not supported by libssl (such as in
Debian 8).
This should be backported to 1.6.
When the txn.done() fiunction is called, the ouput buffer is cleaned,
but the associated relative pointer on the HTTP requests elements
is not reseted.
This patch remove this cleanup, because the output buffer may contain
data to forward.
The direction (request or response) is not propagated in the
sample fecthes called throught Lua. This patch adds the direction
status in some structs (hlua_txn and hlua_smp) to make sure that
the sample fetches will be called with all the information.
The converters can not access to a TXN object, so there are not
impacted the direction. However, the samples used as input of the
Lua converter wrapper are initiliazed with the direction. Thereby,
the struct smp stay consistent.
[wt: needs to be backported to 1.6]
This patch cleanups the direction names. It replaces numeric values,
by the associated defines. It ensure the compliance with values found
somwhere else in HAProxy.
It is required by the bugfix patch which is following.
[wt: needs to be backported to 1.6]
Lua needs to known the direction of the http data processed (request or
response). It checks the flag SMP_OPT_DIR_REQ, buf this flag is 0. This patch
correctly checks the flags after applying the SMP_OPT_DIR mask.
Thierry reported that keep-alive still didn't cope well with Lua
services. The reason is that for now applets have to be closed at
the end of a transaction so we want to work in server-close mode,
which isn't noticeable by the client since it still sees keep-alive.
Additionally we want to enable the request body transfer analyser
which will be needed to synchronize with the response analyser to
indicate the end of the transfer.
Only the main execution function can set the run flag, because it is
the last function before the execution time.
This patch removes the flag set by another function. It will be used
by the new lua timeout counter.
The garbage collector is a little bit heavy to run, and it was added
only for cosockets. This patch prevent useless executions when no
cosockets are used.
When the channel is down, the applet is waked up. Before this patch,
the applet closes the stream and the unread data are discarded.
After this patch, the stream is not closed except if the buffers are
empty.
It will be closed later by the close function, or by the garbage collector.
The HAProxy Lua socket respects the Lua Socket tcp specs. these specs
are a little bit limited, it not permits to connect to unix socket.
this patch extends a little it the specs. It permit to accept a
syntax that begin with "unix@", "ipv4@", "ipv6@", "fd@" or "abns@".
Actions may yield but must not do it during the final call from a ruleset
because it indicates there will be no more opportunity to complete or
clean up. This is indicated by ACT_FLAG_FINAL in the action's flags,
which must be passed to hlua_resume().
Thanks to this, an action called from a TCP ruleset is properly woken
up and possibly finished when the client disconnects.
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.
When a thread stops this patch forces a garbage collection which
cleanup and free the memory.
The HAProxy Lua Socket class contains an HAProxy session, so it
uses a big amount of memory, in other this Socket class uses a
filedescriptor and maintain a connection open.
If the class Socket is stored in a global variable, the Socket stay
alive along of the life of the process (except if it is closed by the
other size, or if a timeout is reached). If the class Socket is stored
in a local variable, it must die with this variable.
The socket is closed by a call from the garbage collector. And the
portability and use of a variable is known by the same garbage collector.
so, running the GC just after the end of all Lua code ensure that the
heavy resources like the socket class are freed quickly.
Not having the target set on the connection causes it to be released
at the last moment, and the destination address to randomly be valid
depending on the data found in the memory at this moment. In practice
it works as long as memory poisonning is disabled. The deep reason is
that connect_server() doesn't expect to be called with SF_ADDR_SET and
an existing connection with !reuse. This causes the release of the
connection, its reallocation (!reuse), and taking the address from the
newly allocated connection. This should certainly be improved.
Commit d75cb0f ("BUG/MAJOR: lua: segfault after the channel data is
modified by some Lua action.") introduced a regression causing an
action run from a TCP rule in an HTTP proxy to end in HTTP error
if it terminated cleanly, because it didn't parse the HTTP request!
Relax the test so that it takes into account the opportunity for the
analysers to parse the message.
The lua code must the the appropriate wakeup mechanism for cosockets.
It wakes them up from outside the stream and outside the applet, so it
shouldn't use the applet's wakeup callback which is designed only for
use from within the applet itself. For now it didn't cause any trouble
(yet).
When an action or a fetch modify the channel data, the http request parser
pointer become inconsistent. This patch detects the modification and call
again the parser.
The function lua_settable uses the metatable for acessing data,
so in the C part, we want to index value in the real table and
not throught the meta-methods. It's much faster this way.
This function is a callback made only for calls from the applet handler.
Rename it to remove confusion. It's currently called from the Lua code
but that's not correct, we should call the notify and update functions
instead otherwise it will not enable the applet again.
The current Lua action are not registered. The executed function is
selected according with a function name writed in the HAProxy configuration.
This patch add an action registration function. The configuration mode
described above disappear.
This change make some incompatibilities with existing configuration files for
HAProxy 1.6-dev.
This couple of function executes securely some Lua calls outside of
the lua runtime environment. Each Lua call can return a longjmp
if it encounter a memory error.
Lua documentation extract:
If an error happens outside any protected environment, Lua calls
a panic function (see lua_atpanic) and then calls abort, thus
exiting the host application. Your panic function can avoid this
exit by never returning (e.g., doing a long jump to your own
recovery point outside Lua).
The panic function runs as if it were a message handler (see
2.3); in particular, the error message is at the top of the
stack. However, there is no guarantee about stack space. To push
anything on the stack, the panic function must first check the
available space (see 4.2).
We must check all the Lua entry point. This includes:
- The include/proto/hlua.h exported functions
- the task wrapper function
- The action wrapper function
- The converters wrapper function
- The sample-fetch wrapper functions
It is tolerated that the initilisation function returns an abort.
Before each Lua abort, an error message is writed on stderr.
The macro SET_SAFE_LJMP initialise the longjmp. The Macro
RESET_SAFE_LJMP reset the longjmp. These function must be macro
because they must be exists in the program stack when the longjmp
is called
All the code which emits error log have the same pattern. Its:
Send log with syslog system, and if it is allowed, display error
log on screen.
This patch replace this pattern by a macro. This reduces the number
of lines.
The send_log function needs a final \n.
This bug is repported by Michael Ezzell.
Minor bug: when writing to syslog from Lua scripts, the last character from
each log entry is truncated.
core.Alert("this is truncated");
Sep 7 15:07:56 localhost haproxy[7055]: this is truncate
This issue appears to be related to the fact that send_log() (in src/log.c)
is expecting a newline at the end of the message's format string:
/*
* This function adds a header to the message and sends the syslog message
* using a printf format string. It expects an LF-terminated message.
*/
void send_log(struct proxy *p, int level, const char *format, ...)
I believe the fix would be in in src/hlua.c at line 760
<http://git.haproxy.org/?p=haproxy.git;a=blob;f=src/hlua.c;h=1e4d47c31e66c16c837ff2aa5ef577f6cafdc7e7;hb=316e3196285b89a917c7d84794ced59a6a5b4eba#l760>,
where this...
send_log(px, level, "%s", trash.str);
...should be adding a newline into the format string to accommodate what
the code expects.
send_log(px, level, "%s\n", trash.str);
This change provides what seems to be the correct behavior:
Sep 7 15:08:30 localhost haproxy[7150]: this is truncated
All other uses of send_log() in hlua.c have a trailing dot "." in the
message that is masking the truncation issue because the output message
stops on a clean word boundary. I suspect these would also benefit from
"\n" appended to their format strings as well, since this appears to be the
pattern seen throughout the rest of the code base.
Reported-by: Michael Ezzell <michael@ezzell.net>
See commit id bdc97a8795
Michael Ezzell reported that the following Lua code fails in
dev4 when the TCP is not established immediately (due to a little
bit of latency):
function tricky_socket()
local sock = core.tcp();
sock:settimeout(3);
core.log(core.alert,"calling connect()\n");
local connected, con_err = sock:connect("x.x.x.x",80);
core.log(core.alert,"returned from connect()\n");
if con_err ~= nil then
core.log(core.alert,"connect() failed with error: '" .. con_err .. "'\n");
end
The problem is that the flags who want to wake up the applet are
resetted before each applet call, so the applet must set again the
flags if the connection is not established.
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.
When called from an http ruleset, txn:done() can still crash the process
because it closes the stream without consuming pending data resulting in
the transaction's buffer representation to differ from the real buffer.
This patch also adjusts the transaction's state to indicate that it's
closed to be consistent with what's already done in redirect rules.
When the Lua execution flow endswith the command done (core.done or txn.done())
an error is detourned, and the stack is no longer usable. This patch juste
reinitilize the stack if this case is detected.
The function txn:close() must be terminal because it demands the session
destruction. This patch renames this function to "done()" to be much
clearer about the fact that it is a final operation.
This patch is inspired by Bowen Ni's proposal and it is based on his first
implementation:
With Lua integration in HAProxy 1.6, one can change the request method,
path, uri, header, response header etc except response line.
I'd like to contribute the following methods to allow modification of the
response line.
[...]
There are two new keywords in 'http-response' that allows you to rewrite
them in the native HAProxy config. There are also two new APIs in Lua that
allows you to do the same rewriting in your Lua script.
Example:
Use it in HAProxy config:
*http-response set-code 404*
Or use it in Lua script:
*txn.http:res_set_reason("Redirect")*
I dont take the full patch because the manipulation of the "reason" is useless.
standard reason are associated with each returned code, and unknown code can
take generic reason.
So, this patch can set the status code, and the reason is automatically adapted.
The function dont remove remaineing analysers and dont update response
channel timeout.
The fix is a copy of the behavior of the functions http_apply_redirect_rule()
and stream_int_retnclose().
Tsvetan Tsvetanov reported that the following Lua code fails in
dev2 and dev3 :
function hello(txn)
local request_msg = txn.req:dup()
local tsm_sock = core.tcp()
tsm_sock:connect("127.0.0.1", 7777)
local res = tsm_sock:send(request_msg)
local response = tsm_sock:receive('*l')
txn.res:send(response)
txn:close()
end
Thierry diagnosed that it was caused by commit 563cc37 ("MAJOR: stream:
use a regular ->update for all stream interfaces"). It broke lua's
ability to establish outgoing connections.
The reason is that the applet used to be notified about established
connections just after the stream analyser loop, and that's not the
case anymore. In peers, this issue didn't happen because peers use
a handshake so after sending data, the response is received and wakes
the applet up again. Here we have to indicate that we want to send or
receive data, this will cause the notification to happen as soon as
the connection is ready. This is similar to pretending that we're
working on a full buffer after all. In theory subscribing for reads
is not needed, but it's added here for completeness.
Reported-By: Tsvetan Tsvetanov <cpi.cecko@gmail.com>
Now the prototype for each action from each section are the same, and
a discriminant for determining for each section we are called are added.
So, this patch removes the wrappers for the action functions called from
more than one section.
This patch removes 132 lines of useless code.
This patch normalize the return code of the configuration parsers. Before
these changes, the tcp action parser returned -1 if fail and 0 for the
succes. The http action returned 0 if fail and 1 if succes.
The normalisation does:
- ACT_RET_PRS_OK for succes
- ACT_RET_PRS_ERR for failure
This patch merges the conguration keyword struct. Each declared configuration
keyword struct are similar with the others. This patch simplify the code.
Action function can return 3 status:
- error if the action encounter fatal error (like out of memory)
- yield if the action must terminate his work later
- continue in other cases
For performances considerations, some actions are not processed by remote
function. They are directly processed by the function. Some of these actions
does the same things but for different processing part (request / response).
This patch give the same name for the same actions, and change the normalization
of the other actions names.
This patch is ONLY a rename, it doesn't modify the code.
This patch group the action name in one file. Some action are called
many times and need an action embedded in the action caller. The main
goal is to have only one header file grouping all definitions.
The (http|tcp)-(request|response) action rules use common
opaque type. For the HAProxy embbedded feature, types are know,
it better to add this types in the action union and use it.
