Allow to set the master CLI in expert or experimental mode. No command
within the master are unlocked yet, but it gives the ability to send
expert or experimental commands to the workers.
echo "@1; experimental-mode on; del server be1/s2" | socat /var/run/haproxy.master -
echo "experimental-mode on; @1 del server be1/s2" | socat /var/run/haproxy.master -
Listeners might be disabled by other threads while running in
listener_accept() due to a stopping condition or possibly a rebinding
error after a failed stop/start. When this happens, the listener's FD
is -1 and accesses made by the lower layers to fdtab[-1] do not end up
well. This can occasionally be noticed if running at high connection
rates in master-worker mode when compiled with ASAN and hammered with
10 reloads per second. From time to time an out-of-bounds error will
be reported.
One approach could consist in keeping a copy of critical information
such as the FD before proceeding but that's not correct since in case of
close() the FD might be reassigned to another connection for example.
In fact what is needed is to read-lock the listener during this operation
so that it cannot change while we're touching it.
Tests have shown that using a spinlock only does generally work well but
it doesn't scale much with threads and we can see listener_accept() eat
10-15% CPU on a 24 thread machine at 300k conn/s. For this reason the
lock was turned to an rwlock by previous commit and this patch only takes
the read lock to make sure other operations do not change the listener's
state while threads are accepting connections. With this approach, no
performance loss was noticed at all and listener_accept() doesn't appear
in perf top.
This ought to be backported to about all branches that make use of the
unlocked listeners, but in practice it seems to mostly concern 2.3 and
above, since 2.2 and older will take the FD in the argument (and the
race exists there, this FD could end up being reassigned in parallel
but there's not much that can be done there to prevent that race; at
least a permanent error will be reported).
For backports, the current approach is preferred, with a preliminary
backport of previous commit "MINOR: listener: replace the listener's
spinlock with an rwlock". However if for any reason this commit cannot
be backported, the current patch can be modified to simply take a
spinlock (tested and works), it will just impact high performance
workloads (like DDoS protection).
We'll need to lock the listener a little bit more during accept() and
tests show that a spinlock is a massive performance killer, so let's
first switch to an rwlock for this lock.
This patch might have to be backported for the next patch to work, and
if so, the change is almost mechanical (look for LISTENER_LOCK), but do
not forget about the few HA_SPIN_INIT() in the file. There's no reference
to this lock outside of listener.c nor listener-t.h.
Implement the idle frontend connection cleanup for QUIC mux. Each
connection is registered on the mux_stopping_list. On process closing,
the mux is notified via a new function qc_wake. This function immediatly
release the connection if the parent proxy is stopped.
This allows to quickly close the process even if there is QUIC
connection stucked on timeout.
Do not close immediatly the connection if there is no bidirectional
stream opened. Schedule instead the mux timeout when this condition is
verified. On the timer expiration, the mux/connection can be freed.
This task will be used to schedule a timer when there is no activity on
the mux. The timeout is set via the "timeout client" from the
configuration file.
The timeout task process schedule the timeout only on specific
conditions. Currently, it's done if there is no opened bidirectional
stream.
For now this task is not used. This will be implemented in the following
commit.
Remove the condition on CONNECTION_CLOSE reception to close immediately
streams. It can cause some crash as the QUIC xprt layer still access the
qcs to send data and handle ACK.
The whole interface and buffering between QUIC xprt and mux must be
properly reorganized to better handle this case. Once this is done, it
may have some sense to free the qcs streams on CONNECTION_CLOSE
reception.
It's among the cases that would provoke memory corruption, let's add
some tests against negative FDs and those larger than the table. This
must never ever happen and would currently result in silent corruption
or a crash. Better have a noticeable one exhibiting the call chain if
that were to happen.
This reverts commit ea7371e93484cd55d712abd720f47bc5fcaa9246.
This can't work correctly as we need this FD in the worker to be
inserted in the fdtab. The correct way to do it would be to cleanup the
mworker_proc in the master after the fork().
In fact the xprt_ctx of the connection is first stored into quic_conn
struct as soon as it is initialized from qc_conn_alloc_ssl_ctx().
As quic_conn_init_timer() is run after this function, we can associate
the timer context of the timer to the one from the quic_conn struct.
We must move this initialization from xprt_start() callback, which
comes too late (after handshake completion for 1RTT session). This timer must be
usable as soon as we have packets to send/receive. Let's initialize it after
the TLS context is initialized in qc_conn_alloc_ssl_ctx(). This latter function
initializes I/O handler task (quic_conn_io_cb) to send/receive packets.
We add a new flag to mark a connection as already enqueued for acception.
This is useful for 0-RTT session where a connection is first enqueued for
acception as soon as 0-RTT RX secrets could be derived. Then as for any other
connection, we could accept one more time this connection after handshake
completion which lead to very bad side effects.
Thank you to Amaury for this nice patch.
mworker_cli_sockpair_new() is used to create the socketpair CLI listener of
the worker. Its FD is referenced in the mworker_proc structure, however,
once it's assigned to the listener the reference should be removed so we
don't use it accidentally.
The same must be done in case of errors if the FDs were already closed.
When starting HAProxy in master-worker, the master pre-allocate a struct
mworker_proc and do a socketpair() before the configuration parsing. If
the configuration loading failed, the FD are never closed because they
aren't part of listener, they are not even in the fdtab.
This patch fixes the issue by cleaning the mworker_proc structure that
were not asssigned a process, and closing its FDs.
Must be backported as far as 2.0, the srv_drop() only frees the memory
and could be dropped since it's done before an exec().
There were a few casts of list* to mt_list* that were upsetting some
old compilers (not sure about the effect on others). We had created
list_to_mt_list() purposely for this, let's use it instead of applying
this cast.
dladdr1() is used on glibc and takes a void**, but we pass it a
const ElfW(Sym)** and some compilers complain that we're aliasing.
Let's just set a may_alias attribute on the local variable to
address this. There's no need to backport this unless warnings are
reported on older distros or uncommon compilers.
At a few places in the code the switch/case ond flags are tested against
64-bit constants without explicitly being marked as long long. Some
32-bit compilers complain that the constant is too large for a long, and
other likely always use long long there. Better fix that as it's uncertain
what others which do not complain do. It may be backported to avoid doubts
on uncommon platforms if needed, as it touches very few areas.
fcgi_trace() declares fconn as a const and casts its mbuf array to
(struct buffer*), which rightfully upsets some older compilers. Better
just declare it as a writable variable and get rid of the cast. It's
harmless anyway. This has been there since 2.1 with commit 5c0f859c2
("MINOR: mux-fcgi/trace: Register a new trace source with its events")
and doens't need to be backported though it would not harm either.
Once in a while we get rid of this one. isblank() is missing on old
C libraries and only matches two values, so let's just replace it.
It was brought with this commit in 2.4:
0bf268e18 ("MINOR: server: Be more strict on the server-state line parsing")
It may be backported though it's really not important.
Compiling vars.c with gcc 4.2 shows that we're initializing some local
structs field members in a not really portable way:
src/vars.c: In function 'vars_parse_cli_set_var':
src/vars.c:1195: warning: initialized field overwritten
src/vars.c:1195: warning: (near initialization for 'px.conf.args')
src/vars.c:1195: warning: initialized field overwritten
src/vars.c:1195: warning: (near initialization for 'px.conf')
src/vars.c:1201: warning: initialized field overwritten
src/vars.c:1201: warning: (near initialization for 'rule.conf')
It's totally harmless anyway, but better clean this up.
These functions are declared as external functions in check.h and
as inline functions in check.c. Let's move them as static inline in
check.h. This appeared in 2.4 with the following commits:
4858fb2e1 ("MEDIUM: check: align agentaddr and agentport behaviour")
1c921cd74 ("BUG/MINOR: check: consitent way to set agentaddr")
While harmless (it only triggers build warnings with some gcc 4.x),
it should probably be backported where the paches above are present
to keep the code consistent.
The man page indicates that CPU_AND() and CPU_ASSIGN() take a variable,
not a const on the source, even though it doesn't make much sense. But
with older libcs, this triggers a build warning:
src/cpuset.c: In function 'ha_cpuset_and':
src/cpuset.c:53: warning: initialization discards qualifiers from pointer target type
src/cpuset.c: In function 'ha_cpuset_assign':
src/cpuset.c:101: warning: initialization discards qualifiers from pointer target type
Better stick stricter to the documented API as this is really harmless
here. There's no need to backport it (unless build issues are reported,
which is quite unlikely).
When the master process is reloaded on a new config, it will try to
connect to the previous process' socket to retrieve all known
listening FDs to be reused by the new listeners. If listeners were
removed, their unused FDs are simply closed.
However there's a catch. In case a socket fails to bind, the master
will cancel its startup and swithc to wait mode for a new operation
to happen. In this case it didn't close the possibly remaining FDs
that were left unused.
It is very hard to hit this case, but it can happen during a
troubleshooting session with fat fingers. For example, let's say
a config runs like this:
frontend ftp
bind 1.2.3.4:20000-29999
The admin wants to extend the port range down to 10000-29999 and
by mistake ends up with:
frontend ftp
bind 1.2.3.41:20000-29999
Upon restart the bind will fail if the address is not present, and the
master will then switch to wait mode without releasing the previous FDs
for 1.2.3.4:20000-29999 since they're now apparently unused. Then once
the admin fixes the config and does:
frontend ftp
bind 1.2.3.4:10000-29999
The service will start, but will bind new sockets, half of them
overlapping with the previous ones that were not properly closed. This
may result in a startup error (if SO_REUSEPORT is not enabled or not
available), in a FD number exhaustion (if the error is repeated many
times), or in connections being randomly accepted by the process if
they sometimes land on the old FD that nobody listens on.
This patch will need to be backported as far as 1.8, and depends on
previous patch:
MINOR: sock: move the unused socket cleaning code into its own function
Note that before 2.3 most of the code was located inside haproxy.c, so
the patch above should probably relocate the function there instead of
sock.c.
The startup code used to scan the list of unused sockets retrieved from
an older process, and to close them one by one. This also required that
the knowledge of the internal storage of these temporary sockets was
known from outside sock.c and that the code was copy-pasted at every
call place.
This patch moves this into sock.c under the name
sock_drop_unused_old_sockets(), and removes the xfer_sock_list
definition from sock.h since the rest of the code doesn't need to know
this.
This cleanup is minimal and preliminary to a future fix that will need
to be backported to all versions featuring FD transfers over the CLI.
In the release callback, ctx.peers was used instead of ctx.sft. Concretly,
it is not an issue because the appctx context is an union and these both
fields are structures with a unique pointer. But it will be a problem if
that changes.
This patch must be backported as far as 2.2.
When a string is converted to a domain name label, the trailing dot must be
ignored. In resolv_str_to_dn_label(), there is a test to do so. However, the
trailing dot is not really ignored. The character itself is not copied but
the string index is still moved to the next char. Thus, this trailing dot is
counted in the length of the last encoded part of the domain name. Worst,
because the copy is skipped, a garbage character is included in the domain
name.
This patch should fix the issue #1528. It must be backported as far as 2.0.
Do not use an extra DCID parameter on new_quic_cid to be able to
associated a new generated CID to a thread ID. Simply do the computation
inside the function. The API is cleaner this way.
This also has the effects to improve the apparent randomness of CIDs.
With the previous version the first byte of all CIDs are identical for a
connection which could lead to privacy issue. This version may not be
totally perfect on this aspect but it improves the situation.
The producer must know where is the tailing hole in the RX buffer
when it purges it from consumed datagram. This is done allocating
a fake datagram with the remaining number of bytes which cannot be produced
at the tail of the RX buffer as length.
The CID trees are no more attached to the listener receiver but to the
underlying datagram handlers (one by thread) which run always on the same thread.
So, any operation on these trees do not require any locking.
We copy the first octet of the original destination connection ID to any CID for
the connection calling new_quic_cid(). So this patch modifies only this function
to take a dcid as passed parameter.
As the RX buffer is not consumed by the sock i/o handler as soon as a datagram
is produced, when full an RX buffer must not be reset. The remaining room is
consumed without modifying it. The consumer has a represention of its contents:
a list of datagrams.
Rename quic_lstnr_dgram_read() to quic_lstnr_dgram_dispatch() to reflect its new role.
After calling this latter, the sock i/o handler must consume the buffer only if
the datagram it received is detected as wrong by quic_lstnr_dgram_dispatch().
The datagram handler task mark the datagram as consumed atomically setting ->buf
to NULL value. The sock i/o handler is responsible of flushing its RX buffer
before using it. It also keeps a datagram among the consumed ones so that
to pass it to quic_lstnr_dgram_dispatch() and prevent it from allocating a new one.
As mentionned in the comment, the tx_qrings and rxbufs members of
receiver struct must be pointers to pointers!
Modify the functions responsible of their allocations consequently.
Note that this code could work because sizeof rxbuf and sizeof tx_qrings
are greater than the size of pointer!
quic_dgram_read() parses all the QUIC packets from a UDP datagram. It is the best
candidate to be converted into a task, because is processing data unit is the UDP
datagram received by the QUIC sock i/o handler. If correct, this datagram is
added to the context of a task, quic_lstnr_dghdlr(), a conversion of quic_dgram_read()
into a task. This task pop a datagram from an mt_list and passes it among to
the packet handler (quic_lstnr_pkt_rcv()).
Modify the quic_dgram struct to play the role of the old quic_dgram_ctx struct when
passed to quic_lstnr_pkt_rcv().
Modify the datagram handlers allocation to set their tasks to quic_lstnr_dghdlr().
Add quic_dghdlr new struct do define datagram handler tasks, one by thread.
Allocate them and attach them to the listener receiver part calling
quic_alloc_dghdlrs_listener() newly implemented function.
Add quic_dgram new structure to store information about datagrams received
by the sock I/O handler (quic_sock_fd_iocb) and its associated pool.
Implement quic_get_dgram_dcid() to retrieve the datagram DCID which must
be the same for all the packets in the datagram.
Modify quic_lstnr_dgram_read() called by the sock I/O handler to allocate
a quic_dgram each time a correct datagram is found and add it to the sock I/O
handler rxbuf dgram list.
This function is no more used anymore, broken and uses code shared with the
listener packet parser. This is becoming anoying to continue to modify
it without testing each time we modify the code it shares with the
listener packet parser.
This is to be sure xprt functions do not manipulate the buffer struct
passed as parameter to quic_lstnr_dgram_read() from low level datagram
I/O callback in quic_sock.c (quic_sock_fd_iocb()).
Mention that the token is sent only by servers in both server and listener
packet parsers.
Remove a "TO DO" section in listener packet parser because there is nothing
more to do in this function about the token
