We need to specially handle protocol families which regroup common
functions used for a given address family. These functions include
bind(), addrcmp(), get_src() and get_dst() for now. Some fields are
also added about the address family, socket domain (protocol family
passed to the socket() syscall), and address length.
These protocol families are referenced from the protocols but not yet
used.
All protocol's listeners now only take care of themselves and not of
the receiver anymore since that's already being done in proto_bind_all().
Now it finally becomes obvious that UDP doesn't need a listener, as the
only thing it does is to set the listener's state to LI_LISTEN!
This removes all the AF_INET-specific code from tcp_bind_listener()
and now simply relies on sock_inet_bind_listener() to do the same
job. The function was now roughly cut in half and its error path
significantly simplified.
This function collects all the receiver-specific code from both
tcp_bind_listener() and udp_bind_listener() in order to provide a more
generic AF_INET/AF_INET6 socket binding function. For now the API is
not very elegant because some info are still missing from the receiver
while there's no ideal place to fill them except when calling ->listen()
at the protocol level. It looks like some polishing code is needed in
check_config_validity() or somewhere around this in order to finalize
the receivers' setup. The main issue is that listeners and receivers
are created *before* bind_conf options are parsed and that there's no
finishing step to resolve some of them.
The function currently sets up a receiver and subscribes it to the
poller. In an ideal world we wouldn't subscribe it but let the caller
do it after having finished to configure the L4 stuff. The problem is
that the caller would then need to perform an fd_insert() call and to
possibly set the exported flag on the FD while it's not its job. Maybe
an improvement could be to have a separate sock_start_receiver() call
in sock.c.
For now the function is not used but it will soon be. It's already
referenced as tcp and udp's ->bind().
The new RX_O_FOREIGN, RX_O_V6ONLY and RX_O_V4V6 options are now set into
the rx_settings part during the parsing, so that we don't need to adjust
them in each and every listener anymore. We have to keep both v4v6 and
v6only due to the precedence from v6only over v4v6.
It's the receiver's FD that's inherited from the parent process, not
the listener's so the flag must move to the receiver so that appropriate
actions can be taken.
In order to split the receiver from the listener, we'll need to know that
a socket is already bound and ready to receive. We used to do that via
tha LI_O_ASSIGNED state but that's not sufficient anymore since the
receiver might not belong to a listener anymore. The new RX_F_BOUND flag
is used for this.
Some socket settings used to be retrieved via the listener and the
bind_conf. Now instead we use the receiver and its settings whenever
appropriate. This will simplify the removal of the dependency on the
listener.
The receiver is the one which depends on the protocol while the listener
relies on the receiver. Let's move the protocol there. Since there's also
a list element to get back to the listener from the proto list, this list
element (proto_list) was moved as well. For now when scanning protos, we
still see listeners which are linked by their rx.proto_list part.
The listening socket is represented by its file descriptor, which is
generic to all receivers and not just listeners, so it must move to
the rx struct.
It's worth noting that in order to extend receivers and listeners to
other protocols such as QUIC, we'll need other handles than file
descriptors here, and that either a union or a cast to uintptr_t
will have to be used. This was not done yet and the field was
preserved under the name "fd" to avoid adding confusion.
The netns is common to all listeners/receivers and is used to bind the
listening socket so it must be in the receiver settings and not in the
listener. This removes some yet another set of unnecessary loops.
The interface is common to all listeners/receivers and is used to bind
the listening socket so it must be in the receiver settings and not in
the listener. This removes some unnecessary loops.
This code was highly redundant, existing for TCP clients, TCP servers
and UDP servers. Let's move it to sock_inet where it belongs. The new
functions are sock_inet4_make_foreign() and sock_inet6_make_foreign().
This is essentially a merge from tcp_find_compatible_fd() and
uxst_find_compatible_fd() that relies on a listener's address and
compare function and still checks for other variations. For AF_INET6
it compares a few of the listener's bind options. A minor change for
UNIX sockets is that transparent mode, interface and namespace used
to be ignored when trying to pick a previous socket while now if they
are changed, the socket will not be reused. This could be refined but
it's still better this way as there is no more risk of using a
differently bound socket by accident.
Eventually we should not pass a listener there but a set of binding
parameters (address, interface, namespace etc...) which ultimately will
be grouped into a receiver. For now this still doesn't exist so let's
stick to the listener to break dependencies in the rest of the code.
Let's determine it at boot time instead of doing it on first use. It
also saves us from having to keep it thread local. It's been moved to
the new sock_inet_prepare() function, and the variables were renamed
to sock_inet_tcp_maxseg_default and sock_inet6_tcp_maxseg_default.
The v6only_default variable is not specific to TCP but to AF_INET6, so
let's move it to the right file. It's now immediately filled on startup
during the PREPARE stage so that it doesn't have to be tested each time.
The variable's name was changed to sock_inet6_v6only_default.
The function now makes it clear that it's independent on the socket
type and solely relies on the address family. Note that it supports
both IPv4 and IPv6 as we don't seem to need it per-family.
This one is common to the TCPv4 and UDPv4 code, it retrieves the
destination address of a socket, taking care of the possiblity that for
an incoming connection the traffic was possibly redirected. The TCP and
UDP definitions were updated to rely on it and remove duplicated code.
The new addrcmp() protocol member points to the function to be used to
compare two addresses of the same family.
When picking an FD from a previous process, we can now use the address
specific address comparison functions instead of having to rely on a
local implementation. This will help move that code to a more central
place.
The new file sock.c will contain generic code for standard sockets
relying on file descriptors. We currently have way too much duplication
between proto_uxst, proto_tcp, proto_sockpair and proto_udp.
For now only get_src, get_dst and sock_create_server_socket were moved,
and are used where appropriate.
Let's continue the cleanup and get rid of all bind and server keywords
parsers from proto_tcp.c. They're now moved to cfgparse-tcp.c, just as
was done for ssl before 2.2 release. Nothing has changed beyond this.
Now proto_tcp.c is clean and only contains code related to binding and
connecting.
Let's continue the cleanup and get rid of all sample fetch functions
from proto_tcp.c. They're now moved to tcp_sample.c, just as was done
for ssl before 2.2 release. Nothing has changed beyond this.
This is totally ugly, smp_fetch_src() is exported only so that stick_table.c
can (ab)use it in the {sc,src}_* sample fetch functions. It could be argued
that the sample could have been reconstructed there in place, but we don't
even need to duplicate the code. We'd rather simply retrieve the "src"
fetch's function from where it's used at init time and be done with it.
The file proto_tcp.c has become a real mess because it still contains
tons of definitions that have nothing to do with the TCP protocol setup.
This commit moves the ruleset actions "set-src-port", "set-dst-port",
"set-src", "set-dst", and "silent-drop" to a new file "tcp_act.c".
Nothing has changed beyond this.
This new flag will be used to mark FDs that must be passed to any future
process across the CLI's "_getsocks" command.
The scheme here is quite complex and full of special cases:
- FDs inherited from parent processes are *not* exported this way, as
they are supposed to instead be passed by the master process itself
across reloads. However such FDs ought never to be paused otherwise
this would disrupt the socket in the parent process as well;
- FDs resulting from a "bind" performed over a socket pair, which are
in fact one side of a socket pair passed inside another control socket
pair must not be passed either. Since all of them are used the same
way, for now it's enough never to put this "exported" flag to FDs
bound by the socketpair code.
- FDs belonging to temporary listeners (e.g. a passive FTP data port)
must not be passed either. Fortunately we don't have such FDs yet.
- the rest of the listeners for now are made of TCP, UNIX stream, ABNS
sockets and are exportable, so they get the flag.
- UDP listeners were wrongly created as listeners and are not suitable
here. Their FDs should be passed but for now they are not since the
client doesn't even distinguish the SO_TYPE of the retrieved sockets.
In addition, it's important to keep in mind that:
- inherited FDs may never be closed in master process but may be closed
in worker processes if the service is shut down (useless since still
bound, but technically possible) ;
- inherited FDs may not be disabled ;
- exported FDs may be disabled because the caller will perform the
subsequent listen() on them. However that might not work for all OSes
- exported FDs may be closed, it just means the service was shut down
from the worker, and will be rebound in the new process. This implies
that we have to disable exported on close().
=> as such, contrary to an apparently obvious equivalence, the "exported"
status doesn't imply anything regarding the ability to close a
listener's FD or not.
Let's not look at the listener options passed by the original process
and determine from the socket itself whether it is configured for
transparent mode or not. This is cleaner and safer, and doesn't rely
on flag values that could possibly change between versions.
The v4v6 and v6only options are passed as data during the socket transfer
between processes so that the new process can decide whether it wants to
reuse a socket or not. But this actually misses one point: if no such option
is set and the OS defaults are changed between the reloads, then the socket
will still be inherited and will never be rebound using the new options.
This can be seen by starting the following config:
global
stats socket /tmp/haproxy.sock level admin expose-fd listeners
frontend testme
bind :::1234
timeout client 2000ms
Having a look at the OS settins, v6only is disabled:
$ cat /proc/sys/net/ipv6/bindv6only
0
A first check shows it's indeed bound to v4 and v6:
$ ss -an -6|grep 1234
tcp LISTEN 0 2035 *:1234 *:*
Reloading the process doesn't change anything (which is expected). Now let's set
bindv6only:
$ echo 1 | sudo tee /proc/sys/net/ipv6/bindv6only
1
$ cat /proc/sys/net/ipv6/bindv6only
1
Reloading gives the same state:
$ ss -an -6|grep 1234
tcp LISTEN 0 2035 *:1234 *:*
However a restart properly shows a correct bind:
$ ss -an -6|grep 1234
tcp LISTEN 0 2035 [::]:1234 [::]:*
This one doesn't change once bindv6only is reset, for the same reason.
This patch attacks this problem differently. Instead of passing the two
options at once for each listening fd, it ignores the options and reads
the socket's current state for the IPV6_V6ONLY flag and sets it only.
Then before looking for a compatible FD, it checks the OS's defaults
before deciding which of the v4v6 and v6only needs to be kept on the
listener. And the selection is only made on this.
First, it addresses this issue. Second, it also ensures that if such
options are changed between reloads to identical states, the socket
can still be inherited. For example adding v4v6 when bindv6only is not
set will allow the socket to still be usable. Third, it avoids an
undesired dependency on the LI_O_* bit values between processes across
a reload (for these ones at least).
It might make sense to backport this to some recent stable versions, but
quite frankly the likelyhood that anyone will ever notice it is extremely
faint.
If a socket was already bound (inherited from a parent or retrieved from
a previous process), there's no point trying to change its IPV6_V6ONLY
state since it will fail. This is visible in strace as an EINVAL during
a reload when passing FDs.
This way, all fields of the buffer structure are reset when a string argument
(ARGT_STR) is released. It is also a good way to explicitly specify this kind
of argument is a chunk. So .data and .size fields must be set.
This patch may be backported to ease backports.
When a connect() doesn't immediately succeed (i.e. most of the times),
fd_cant_send() is called to enable polling. But given that we don't
mark that we cannot receive either, we end up performing a failed
recvfrom() immediately when the connect() is finally confirmed, as
indicated in issue #253.
This patch simply adds fd_cant_recv() as well so that we're only
notified once the recv path is ready. The reason it was not there
is purely historic, as in the past when there was the fd cache,
doing it would have caused a pending recv request to be placed into
the fd cache, hence a useless recvfrom() upon success (i.e. what
happens now).
Without this patch, forwarding 100k connections does this:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
17.51 0.704229 7 100000 100000 connect
16.75 0.673875 3 200000 sendto
16.24 0.653222 3 200036 close
10.82 0.435082 1 300000 100000 recvfrom
10.37 0.417266 1 300012 setsockopt
7.12 0.286511 1 199954 epoll_ctl
6.80 0.273447 2 100000 shutdown
5.34 0.214942 2 100005 socket
4.65 0.187137 1 105002 5002 accept4
3.35 0.134757 1 100004 fcntl
0.61 0.024585 4 5858 epoll_wait
With the patch:
% time seconds usecs/call calls errors syscall
------ ----------- ----------- --------- --------- ----------------
18.04 0.697365 6 100000 100000 connect
17.40 0.672471 3 200000 sendto
17.03 0.658134 3 200036 close
10.57 0.408459 1 300012 setsockopt
7.69 0.297270 1 200000 recvfrom
7.32 0.282934 1 199922 epoll_ctl
7.09 0.274027 2 100000 shutdown
5.59 0.216041 2 100005 socket
4.87 0.188352 1 104697 4697 accept4
3.35 0.129641 1 100004 fcntl
0.65 0.024959 4 5337 1 epoll_wait
Note the total disappearance of 1/3 of failed recvfrom() *without*
adding any extra syscall anywhere else.
The trace of an HTTP health check is now totally clean, with no useless
syscall at all anymore:
09:14:21.959255 connect(9, {sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("127.0.0.1")}, 16) = -1 EINPROGRESS (Operation now in progress)
09:14:21.959292 epoll_ctl(4, EPOLL_CTL_ADD, 9, {EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=9, u64=9}}) = 0
09:14:21.959315 epoll_wait(4, [{EPOLLOUT, {u32=9, u64=9}}], 200, 1000) = 1
09:14:21.959376 sendto(9, "OPTIONS / HTTP/1.0\r\ncontent-leng"..., 41, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 41
09:14:21.959436 epoll_wait(4, [{EPOLLOUT, {u32=9, u64=9}}], 200, 1000) = 1
09:14:21.959456 epoll_ctl(4, EPOLL_CTL_MOD, 9, {EPOLLIN|EPOLLRDHUP, {u32=9, u64=9}}) = 0
09:14:21.959512 epoll_wait(4, [{EPOLLIN|EPOLLRDHUP, {u32=9, u64=9}}], 200, 1000) = 1
09:14:21.959548 recvfrom(9, "HTTP/1.0 200\r\nContent-length: 0\r"..., 16320, 0, NULL, NULL) = 126
09:14:21.959570 close(9) = 0
With the edge-triggered poller, it gets even better:
09:29:15.776201 connect(9, {sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("127.0.0.1")}, 16) = -1 EINPROGRESS (Operation now in progress)
09:29:15.776256 epoll_ctl(4, EPOLL_CTL_ADD, 9, {EPOLLIN|EPOLLOUT|EPOLLRDHUP|EPOLLET, {u32=9, u64=9}}) = 0
09:29:15.776287 epoll_wait(4, [{EPOLLOUT, {u32=9, u64=9}}], 200, 1000) = 1
09:29:15.776320 sendto(9, "OPTIONS / HTTP/1.0\r\ncontent-leng"..., 41, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 41
09:29:15.776374 epoll_wait(4, [{EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=9, u64=9}}], 200, 1000) = 1
09:29:15.776406 recvfrom(9, "HTTP/1.0 200\r\nContent-length: 0\r"..., 16320, 0, NULL, NULL) = 126
09:29:15.776434 close(9) = 0
It could make sense to backport this patch to 2.2 and maybe 2.1 after
it has been sufficiently checked for absence of side effects in 2.3-dev,
as some people had reported an extra overhead like in issue #168.
To set a connection as private, the conn_set_private() function must now be
called. It sets the CO_FL_PRIVATE flags, but it also remove the connection from
the available connection list, if necessary. For now, it never happens because
only HTTP/1 connections may be set as private after their creation. And these
connections are never inserted in the available connection list.
Previous commit b24bc0d ("MINOR: tcp: Support TCP keepalive parameters
customization") broke non-Linux builds as TCP_KEEP{CNT,IDLE,INTVL} are
not necessarily defined elsewhere.
This patch adds the required #ifdefs to condition the visibility of the
keywords, and adds a mention in the doc about their dependency on Linux.
It is now possible to customize TCP keepalive parameters.
These correspond to the socket options TCP_KEEPCNT, TCP_KEEPIDLE, TCP_KEEPINTVL
and are valid for the defaults, listen, frontend and backend sections.
This patch fixes GitHub issue #670.
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
This one was not easy because it was embarking many includes with it,
which other files would automatically find. At least global.h, arg.h
and tools.h were identified. 93 total locations were identified, 8
additional includes had to be added.
In the rare files where it was possible to finalize the sorting of
includes by adjusting only one or two extra lines, it was done. But
all files would need to be rechecked and cleaned up now.
It was the last set of files in types/ and proto/ and these directories
must not be reused anymore.
extern struct dict server_name_dict was moved from the type file to the
main file. A handful of inlined functions were moved at the bottom of
the file. Call places were updated to use server-t.h when relevant, or
to simply drop the entry when not needed.
This one is particularly difficult to split because it provides all the
functions used to manipulate a proxy state and to retrieve names or IDs
for error reporting, and as such, it was included in 73 files (down to
68 after cleanup). It would deserve a small cleanup though the cut points
are not obvious at the moment given the number of structs involved in
the struct proxy itself.
The current state of the logging is a real mess. The main problem is
that almost all files include log.h just in order to have access to
the alert/warning functions like ha_alert() etc, and don't care about
logs. But log.h also deals with real logging as well as log-format and
depends on stream.h and various other things. As such it forces a few
heavy files like stream.h to be loaded early and to hide missing
dependencies depending where it's loaded. Among the missing ones is
syslog.h which was often automatically included resulting in no less
than 3 users missing it.
Among 76 users, only 5 could be removed, and probably 70 don't need the
full set of dependencies.
A good approach would consist in splitting that file in 3 parts:
- one for error output ("errors" ?).
- one for log_format processing
- and one for actual logging.
It was moved without any change, however many callers didn't need it at
all. This was a consequence of the split of proto_http.c into several
parts that resulted in many locations to still reference it.
The type file is becoming a mess, half of it is for the proxy protocol,
another good part describes conn_streams and mux ops, it would deserve
being split again. At least it was reordered so that elements are easier
to find, with the PP-stuff left at the end. The MAX_SEND_FD macro was moved
to compat.h as it's said to be the value for Linux.
