This is the same fixe as for this commit:
"BUILD: tree-wide: avoid warnings caused by redundant checks of obj_types"
Should fix CID 1469649 for GH #1546
Move the QUIC datagram handlers oustide of the receivers. Use a global
handler per-thread which is allocated on post-config. Implement a free
function on process deinit to avoid a memory leak.
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.
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.
Do not proceed to direct accept when creating a new quic_conn. Wait for
the QUIC handshake to succeeds to insert the quic_conn in the accept
queue. A tasklet is then woken up to call listener_accept to accept the
quic_conn.
The most important effect is that the connection/mux layers are not
instantiated at the same time as the quic_conn. This forces to delay
some process to be sure that the mux is allocated :
* initialization of mux transport parameters
* installation of the app-ops
Also, the mux instance is not checked now to wake up the quic_conn
tasklet. This is safe because the xprt-quic code is now ready to handle
the absence of the connection/mux layers.
Note that this commit has a deep impact as it changes significantly the
lower QUIC architecture. Most notably, it breaks the 0-RTT feature.
Create a new type quic_accept_queue to handle QUIC connections accept.
A queue will be allocated for each thread. It contains a list of
listeners which contains at least one quic_conn ready to be accepted and
the tasklet to run listener_accept for these listeners.
Mark QUIC listeners with the flag LI_F_QUIC_LISTENER. It is set by the
proto-quic layer on the add listener callback. This allows to override
more clearly the accept callback on quic_session_accept.
QUIC connections are distributed accross threads by xprt-quic according
to their CIDs. As such disable the thread selection in listener_accept
for QUIC listeners.
This prevents connection from migrating to another threads after its
allocation which can results in unexpected side-effects.
Define a special accept cb for QUIC listeners to quic_session_accept().
This operation is conducted during the proto.add callback when creating
listeners.
A special care is now taken care when setting the standard callback
session_accept_fd() to not overwrite if already defined by the proto
layer.
At this time we allocate an RX buffer by thread.
Also take the opportunity offered by this patch to rename TX related variable
names to distinguish them from the RX part.
The protocol selection is currently performed based on the family,
control type and socket type. But this is often not enough, as both
only provide DGRAM or STREAM, leaving few variants. Protocols like
SCTP for example might be indistinguishable from TCP here. Same goes
for TCP extensions like MPTCP.
This commit introduces a new enum proto_type that is placed in each
and every protocol definition, that will usually more or less match
the sock_type, but being an enum, will support additional values.
Some protocols fail with "error blah [ip:port]" and other fail with
"[ip:port] error blah". All this already appears in a "starting" or
"binding" context after a proxy name. Let's choose a more universal
approach like below where the ip:port remains at the end of the line
prefixed with "for".
[WARNING] (18632) : Binding [binderr.cfg:10] for proxy http: cannot bind receiver to device 'eth2' (No such device) for [0.0.0.0:1080]
[WARNING] (18632) : Starting [binderr.cfg:10] for proxy http: cannot set MSS to 12 for [0.0.0.0:1080]
We allocate an array of QUIC ring buffer, one by thread, and arranges them in a
MT_LIST. Everything is allocated or nothing: we do not want to usse an incomplete
array of ring buffers to ensure that each thread may safely acquire one of these
buffers.
Modify the I/O dgram handler principal function used to parse QUIC packets
be thread safe. Its role is at least to create new incoming connections
add to two trees protected by the same RW lock. The packets are for now on
fully parsed before possibly creating new connections.
No need to keep this flag apart any more, let's merge it into the global
state. The CLI's output state was extended to 6 digits and the linger/cloned
flags moved inside the parenthesis.
Historically we've used SOL_IP/SOL_IPV6/SOL_TCP everywhere as the socket
level value in getsockopt() and setsockopt() but as we've seen over time
it regularly broke the build and required to have them defined to their
IPPROTO_* equivalent. The Linux ip(7) man page says:
Using the SOL_IP socket options level isn't portable; BSD-based
stacks use the IPPROTO_IP level.
And it indeed looks like a pure linuxism inherited from old examples and
documentation. strace also reports SOL_* instead of IPPROTO_*, which does
not help... A check to linux/in.h shows they have the same values. Only
SOL_SOCKET and other non-IP values make sense since there is no IPPROTO
equivalent.
Let's get rid of this annoying confusion by removing all redefinitions of
SOL_IP/IPV6/TCP and using IPPROTO_* instead, just like any other operating
system. This also removes duplicated tests for the same value.
Note that this should not result in exposing syscalls to other OSes
as the only ones that were still conditionned to SOL_IPV6 were for
IPV6_UNICAST_HOPS which already had an IPPROTO_IPV6 equivalent, and
IPV6_TRANSPARENT which is Linux-specific.
Introduce a new XPRT method, start(). The init() method will now only
initialize whatever is needed for the XPRT to run, but any action the XPRT
has to do before being ready, such as handshakes, will be done in the new
start() method. That way, we will be sure the full stack of xprt will be
initialized before attempting to do anything.
The init() call is also moved to conn_prepare(). There's no longer any reason
to wait for the ctrl to be ready, any action will be deferred until start(),
anyway. This means conn_xprt_init() is no longer needed.
This patch adds a quic_transport_params struct to bind_conf struct
used for the listeners. This is to store the QUIC transport parameters
for the listeners. Also initializes them when calling str2listener().
Before str2sa_range() it's too early to figure we're going to speak QUIC,
and after it's too late as listeners are already created. So it seems that
doing it in str2listener() when the protocol is discovered is the best
place.
Also adds two ebtrees to the underlying receivers to store the connection
by connections IDs (one for the original connection IDs, and another
one for the definitive connection IDs which really identify the connections.
However it doesn't seem normal that it is stored in the receiver nor the
listener. There should be a private context in the listener so that
protocols can store internal information. This element should in
fact be the listener handle.
Something still feels wrong, and probably we'll have to make QUIC and
SSL co-exist: a proof of this is that there's some explicit code in
bind_parse_ssl() to prevent the "ssl" keyword from replacing the xprt.
We add src/quic_sock.c QUIC specific socket management functions as callbacks
for the control layer: ->accept_conn, ->default_iocb and ->rx_listening.
accept_conn() will have to be defined. The default I/O handler only recvfrom()
the datagrams received. Furthermore, ->rx_listening callback always returns 1 at
this time but should returns 0 when reloading the processus.
As QUIC is a connection oriented protocol, this file is almost a copy of
proto_tcp without TCP specific features. To suspend/resume a QUIC receiver
we proceed the same way as for proto_udp receivers.
With the recent updates to the listeners, we don't need a specific set of
quic*_add_listener() functions, the default ones are sufficient. The fields
declaration were reordered to make the various layers more visible like in
other protocols.
udp_suspend_receiver/udp_resume_receiver are up-to-date (the check for INHERITED
is present) and the code being UDP-specific, it's normal to use UDP here.
Note that in the future we might more reasily reference stacked layers so that
there's no more need for specifying the pointer here.