This removes all the AF_INET-specific code from udp_bind_listener()
and now simply relies on sock_inet_bind_listener() to do the same
job. The function is now basically just a wrapper around
sock_inet_bind_receiver().
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.
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 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.
This patch introduce a new fd handler used to parse syslog
message on udp.
The parsing function returns level, facility and metadata that
can be immediatly reused to forward message to a log server.
This handler is enabled on udp listeners if proxy is internally set
to mode PR_MODE_SYSLOG
This patch introduce proto_udp.c targeting a further support of
log forwarding feature.
This code was originally produced by Frederic Lecaille working on
QUIC support and only minimal requirements for syslog support
have been merged.
The set of files proto_udp.{c,h} were misleadingly named, as they do not
provide anything related to the UDP protocol but to datagram handling
instead, since currently all UDP processing is hard-coded where it's used
(dns, logs). They are to UDP what connection.{c,h} are to proto_tcp. This
was causing confusion about how to insert UDP socket management code,
so let's rename them right now to dgram.{c,h} which more accurately
matches what's inside since every function and type is already prefixed
with "dgram_".
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.
global.h was one of the messiest files, it has accumulated tons of
implicit dependencies and declares many globals that make almost all
other file include it. It managed to silence a dependency loop between
server.h and proxy.h by being well placed to pre-define the required
structs, forcing struct proxy and struct server to be forward-declared
in a significant number of files.
It was split in to, one which is the global struct definition and the
few macros and flags, and the rest containing the functions prototypes.
The UNIX_MAX_PATH definition was moved to compat.h.
A few includes were missing in each file. A definition of
struct polled_mask was moved to fd-t.h. The MAX_POLLERS macro was
moved to defaults.h
Stdio used to be silently inherited from whatever path but it's needed
for list_pollers() which takes a FILE* and which can thus not be
forward-declared.
This is a complement to previous fix for bug #399. The exclusion between
the recv() and send() calls prevents send handlers from being called if
rx readiness is reported. The DNS code can trigger this situations with
threads where the fd_recv_ready() flag disappears between the test in
dgram_fd_handler() and the second test in dns_resolve_recv() while a
thread calls fd_cant_recv(), and this situation can sustain itself for
a while. With 8 threads and an error in the socket queue, placing a
printf on the return statement in dns_resolve_recv() scrolls very fast.
Simply removing the "else" in dgram_fd_handler() addresses the issue.
This fix must be backported as far as 1.6.
There's quite some inconsistency in the internal API. listener_accept()
which is the main accept() function returns void but is declared as int
in the include file. It's assigned to proto->accept() for all stream
protocols where an int is expected but the result is never checked (nor
is it documented by the way). This proto->accept() is in turn assigned
to fd->iocb() which is supposed to return an int composed of FD_WAIT_*
flags, but which is never checked either.
So let's fix all this mess :
- nobody checks accept()'s return
- nobody checks iocb()'s return
- nobody sets a return value
=> let's mark all these functions void and keep the current ones intact.
Additionally we now include listener.h from listener.c to ensure we won't
silently hide this incoherency in the future.
Note that this patch could/should be backported to 1.6 and even 1.5 to
simplify debugging sessions.
Basic introduction of a UDP layer in HAProxy. It can be used as a
client only and manages UDP exchanges with servers.
It can't be used to load-balance UDP protocols, but only used by
internal features such as DNS resolution.
