Allocate quic-conn owned socket if possible. This requires that this is
activated in haproxy configuration. Also, this is done only if local
address is known so it depends on the support of IP_PKTINFO.
For the moment this socket is not used. This causes QUIC support to be
broken as received datagram are not read. This commit will be completed
by a following patch to support recv operation on the newly allocated
socket.
This change is part of quic-conn owned socket implementation.
It may be backported to 2.7 after a period of observation.
QUIC protocol support address migration which allows to maintain the
connection even if client has changed its network address. This is done
through address migration.
RFC 9000 stipulates that address migration is forbidden before handshake
has been completed. Add a check for this : drop silently every datagram
if client network address has changed until handshake completion.
This commit is one of the first steps towards QUIC connection migration
support.
This should be backported up to 2.7.
Detect connection migration attempted by the client. This is done by
comparing addresses stored in quic-conn with src/dest addresses of the
UDP datagram.
A new function qc_handle_conn_migration() has been added. For the
moment, no operation is conducted and the function will be completed
during connection migration implementation. The only notable things is
the increment of a new counter "quic_conn_migration_done".
This should be backported up to 2.7.
Extract individual datagram parsing code outside of datagrams list loop
in quic_lstnr_dghdlr(). This is moved in a new function named
quic_dgram_parse().
To complete this change, quic_lstnr_dghdlr() has been moved into
quic_sock source file : it belongs to QUIC socket lower layer and is
directly called by quic_sock_fd_iocb().
This commit will ease implementation of quic-conn owned socket.
New function quic_dgram_parse() will be easily usable after a receive
operation done on quic-conn IO-cb.
This should be backported up to 2.7.
quic_rx_packet struct had a reference to the quic_conn instance. This is
useless as qc instance is always passed through function argument. In
fact, pkt.qc is used only in qc_pkt_decrypt() on key update, even though
qc is also passed as argument.
Simplify this by removing qc field from quic_rx_packet structure
definition. Also clean up qc_pkt_decrypt() documentation and interface
to align it with other quic-conn related functions.
This should be backported up to 2.7.
qc_dgrams_retransmit() could reuse the same local list and could splice it two
times to the packet number space list of frame to be send/resend. This creates a
loop in this list and makes qc_build_frms() possibly endlessly loop when trying
to build frames from the packet number space list of frames. Then haproxy aborts.
This issue could be easily reproduced patching qc_build_frms() function to set <dlen>
variable value to 0 after having built at least 10 CRYPTO frames and using ngtcp2
as client with 30% packet loss in both direction.
Thank you to @gabrieltz for having reported this issue in GH #1903.
Must be backported to 2.6.
Gcc 6.5 is now well known for triggering plenty of false "may be used
uninitialized", particularly at -O1, and two of them happen in quic,
quic_tp and quic_conn. Both of them were reviewed and easily confirmed
as wrong (gcc seems to ignore the control flow after the function
returns and believes error conditions are not met). Let's just preset
the variables that bothers it. In quic_tp the initialization was moved
out of the loop since there's no point inflating the code just to
silence a stupid warning.
This previous patch was not sufficient to prevent haproxy from
crashing when some Handshake packets had to be inspected before being possibly
retransmitted:
"BUG/MAJOR: quic: Crash upon retransmission of dgrams with several packets"
This patch introduced another issue: access to packets which have been
released because still attached to others (in the same datagram). This was
the case for instance when discarding the Initial packet number space before
inspecting an Handshake packet in the same datagram through its ->prev or
member in our case.
This patch implements quic_tx_packet_dgram_detach() which detaches a packet
from the adjacent ones in the same datagram to be called when ackwowledging
a packet (as done in the previous commit) and when releasing its memory. This
was, we are sure the released packets will not be accessed during retransmissions.
Thank you to @gabrieltz for having reported this issue in GH #1903.
Must be backported to 2.6.
As revealed by some traces provided by @gabrieltz in GH #1903 issue,
there are clients (chrome I guess) which acknowledge only one packet among others
in the same datagram. This is the case for the first datagram sent by a QUIC haproxy
listener made an Initial packet followed by an Handshake one. In this identified
case, this is the Handshake packet only which is acknowledged. But if the
client is able to respond with an Handshake packet (ACK frame) this is because
it has successfully parsed the Initial packet. So, why not also acknowledging it?
AFAIK, this is mandatory. On our side, when restransmitting this datagram, the
Handshake packet was accessed from the Initial packet after having being released.
Anyway. There is an issue on our side. Obviously, we must not expect an
implementation to respect the RFC especially when it want to build an attack ;)
With this simple patch for each TX packet we send, we also set the previous one
in addition to the next one. When a packet is acknowledged, we detach the next one
and the next one in the same datagram from this packet, so that it cannot be
resent when resending these packets (the previous one, in our case).
Thank you to @gabrieltz for having reported this issue.
Must be backported to 2.6.
Add more traces to follow CRYPTO data buffering in ncbuf. Offset for
quic_enc_level is now reported for event QUIC_EV_CONN_PRHPKTS. Also
ncb_advance() must never fail so a BUG_ON() statement is here to
guarantee it.
This was useful to track handshake failure reported too often. This is
related to github issue #1903.
This should be backported up to 2.6.
Liberate quic_enc_level ncbuf in quic_stream_free(). In most cases, this
will already be done when handshake is completed via
qc_treat_rx_crypto_frms(). However, if a connection is released before
handshake completion, a leak was present without this patch.
Under normal situation, this leak should have been limited due to the
majority of QUIC connection success on handshake. However, another bug
caused handshakes to fail too frequently, especially with chrome client.
This had the side-effect to dramatically increase this memory leak.
This should fix in part github issue #1903.
QUIC handshakes were frequently in error due to haproxy misuse of
ncbuf. This resulted in one of the following scenario :
- handshake rejected with CONNECTION_CLOSE due to overlapping data
rejected
- CRYPTO data fully received by haproxy but handshake completion signal
not reported causing the client to emit PING repeatedly before timeout
This was produced because ncb_advance() result was not checked after
providing crypto data to the SSL stack in qc_provide_cdata(). However,
this operation can fail if a too small gap is formed. In the meantime,
quic_enc_level offset was always incremented. In some cases, this caused
next ncb_add() to report rejected overlapping data. In other cases, no
error was reported but SSL stack never received the end of CRYPTO data.
Change slightly the handling of new CRYPTO frames to avoid this bug :
when receiving a CRYPTO frame for the current offset, handle them
directly as previously done only if quic_enc_level ncbuf is empty. In
the other case, copy them to the buffer before treating contiguous data
via qc_treat_rx_crypto_frms().
This change ensures that ncb_advance() operation is now conducted only
in a data block : thus this is guaranteed to never fail.
This bug was easily reproduced with chromium as it fragments CRYPTO
frames randomly in several frames out of order.
This commit has two drawbacks :
- it is slightly less worst on performance because as sometimes even
data at the current offset will be memcpy
- if a client uses too many fragmented CRYPTO frames, this can cause
repeated ncb_add() error on gap size. This can be reproduced with
chrome, albeit with a slighly less frequent rate than the fixed issue.
This change should fix in part github issue #1903.
This must be backported up to 2.6.
With GCC 12.2.0 and O2 optimization activated, compiler reports the
following warning for qc_release_lost_pkts().
In function ‘quic_tx_packet_refdec’,
inlined from ‘qc_release_lost_pkts.constprop’ at src/quic_conn.c:2056:3:
include/haproxy/atomic.h:320:41: error: ‘__atomic_sub_fetch_4’ writing 4 bytes into a region of size 0 overflows the destination [-Werror=stringop-overflow=]
320 | #define HA_ATOMIC_SUB_FETCH(val, i) __atomic_sub_fetch(val, i, __ATOMIC_SEQ_CST)
| ^~~~~~~~~~~~~~~~~~
include/haproxy/quic_conn.h:499:14: note: in expansion of macro ‘HA_ATOMIC_SUB_FETCH’
499 | if (!HA_ATOMIC_SUB_FETCH(&pkt->refcnt, 1)) {
| ^~~~~~~~~~~~~~~~~~~
GCC thinks that quic_tx_packet_refdec() can be called with a NULL
argument from qc_release_lost_pkts() with <oldest_lost> as arg.
This warning is a false positive as <oldest_lost> cannot be NULL in
qc_release_lost_pkts() at this stage. This is due to the previous check
to ensure that <pkts> list is not empty.
This warning is silenced by using ALREADY_CHECKED() macro.
This should be backported up to 2.6.
This should fix github issue #1852.
Subscribing was not properly designed between quic-conn and quic MUX
layers. Align this as with in other haproxy components : <subs> field is
moved from the MUX to the quic-conn structure. All mention of qcc MUX is
cleaned up in quic_conn_subscribe()/quic_conn_unsubscribe().
Thanks to this change, ACK reception notification has been simplified.
It's now unnecessary to check for the MUX existence before waking it.
Instead, if <subs> quic-conn field is set, just wake-up the upper layer
tasklet without mentionning MUX. This should probably be extended to
other part in quic-conn code.
This should be backported up to 2.6.
On Initial packet reception, token is checked for validity through
quic_retry_token_check() function. However, some related parts were left
in the parent function quic_rx_pkt_retrieve_conn(). Move this code
directly into quic_retry_token_check() to facilitate its call in various
context.
The API of quic_retry_token_check() has also been refactored. Instead of
working on a plain char* buffer, it now uses a quic_rx_packet instance.
This helps to reduce the number of parameters.
This change will allow to check Retry token even if data were received
with a FD-owned quic-conn socket. Indeed, in this case,
quic_rx_pkt_retrieve_conn() call will probably be skipped.
This should be backported up to 2.6.
Sometimes, a packet is dropped on reception. Several goto statements are
used, mostly to increment a proxy drop counter or drop silently the
packet. However, this labels are interleaved. Re-arrang goto labels to
simplify this process :
* drop label is used to drop a packet with counter incrementation. This
is the default method.
* drop_silent is the next label which does the same thing but skip the
counter incrementation. This is useful when we do not need to report
the packet dropping operation.
This should be backported up to 2.6.
This change is the following of qc_lstnr_pkt_rcv() refactoring. This
function has finally been split into several ones.
The first half is renamed quic_rx_pkt_parse(). This function is
responsible to parse a QUIC packet header and calculate the packet
length.
QUIC connection retrieval has been extracted and is now called directly
by quic_lstnr_dghdlr().
The second half of qc_lstnr_pkt_rcv() is renamed to qc_rx_pkt_handle().
This function is responsible to copy a QUIC packet content to a
quic-conn receive buffer.
A third function named qc_rx_check_closing() is responsible to detect if
the connection is already in closing state. As this requires to drop the
whole datagram, it seems justified to be in a separate function.
This change has no functional impact. It is part of a refactoring series
on qc_lstnr_pkt_rcv(). The objective is to facilitate the integration of
FD-owned quic-conn socket patches.
This should be backported up to 2.6.
Simplify qc_lstnr_pkt_rcv() by extracting code responsible to retrieve
the quic-conn instance. This code is put in a dedicated function named
quic_rx_pkt_retrieve_conn(). This new function could be skipped if a
FD-owned quic-conn socket is used.
The first traces of qc_lstnr_pkt_rcv() have been clean up as qc instance
is always NULL here : thus qc parameter can be removed without any
change.
This change has no functional impact. It is a part of a refactoring
series on qc_lstnr_pkt_rcv(). The objective is facilitate integration of
FD-owned socket patches.
This should be backported up to 2.6.
Received packets treatment has some difference regarding if this is the
first one or not of the encapsulating datagram. Previously, this was set
via a function argument. Simplify this by defining a new Rx packet flag
named QUIC_FL_RX_PACKET_DGRAM_FIRST.
This change does not have functional impact. It will simplify API when
qc_lstnr_pkt_rcv() is broken into several functions : their number of
arguments will be reduced thanks to this patch.
This should be backported up to 2.6.
pn_offset field was only set if header protection cannot be removed.
Extend the usage of this field : it is now set everytime on packet
parsing in qc_lstnr_pkt_rcv().
This change helps to clean up API of Rx functions by removing
unnecessary variables and function argument.
This change has no functional impact. It is a part of a refactoring
series on qc_lstnr_pkt_rcv(). The objective is facilitate integration of
FD-owned socket patches.
This should be backported up to 2.6.
Add a new field version on quic_rx_packet structure. This is set on
header parsing in qc_lstnr_pkt_rcv() function.
This change has no functional impact. It is a part of a refactoring
series on qc_lstnr_pkt_rcv(). The objective is facilitate integration of
FD-owned socket patches.
This should be backported up to 2.6.
When generating a Retry token, client CID is used as encryption input.
The client must reuse the same CID when emitting the token in a new
Initial packet.
A memory overflow can occur on quic_generate_retry_token() depending on
the size of client CID. This is because space reserved for <aad> only
accounted for QUIC_HAP_CID_LEN (size of haproxy owned generated CID).
However, the client CID size only depends on client parameter and is
instead limited to QUIC_CID_MAXLEN as specified in RFC9000.
This was reproduced with ngtcp2 and haproxy built with ASAN. Here is the error
log :
==14964==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7fffee228cee at pc 0x7ffff785f427 bp 0x7fffee2289e0 sp 0x7fffee228188
WRITE of size 17 at 0x7fffee228cee thread T5
#0 0x7ffff785f426 in __interceptor_memcpy /usr/src/debug/gcc/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:827
#1 0x555555906ea7 in quic_generate_retry_token_aad src/quic_conn.c:5452
#2 0x555555907e72 in quic_retry_token_check src/quic_conn.c:5577
#3 0x55555590d01e in qc_lstnr_pkt_rcv src/quic_conn.c:6103
#4 0x5555559190fa in quic_lstnr_dghdlr src/quic_conn.c:7179
#5 0x555555eb0abf in run_tasks_from_lists src/task.c:590
#6 0x555555eb285f in process_runnable_tasks src/task.c:855
#7 0x555555d9118f in run_poll_loop src/haproxy.c:2853
#8 0x555555d91f88 in run_thread_poll_loop src/haproxy.c:3042
#9 0x7ffff709f8fc (/usr/lib/libc.so.6+0x868fc)
#10 0x7ffff7121a5f (/usr/lib/libc.so.6+0x108a5f)
This must be backported up to 2.6.
Right now the QUIC thread mapping derives the thread ID from the CID
by dividing by global.nbthread. This is a problem because this makes
QUIC work on all threads and ignores the "thread" directive on the
bind lines. In addition, only 8 bits are used, which is no more
compatible with the up to 4096 threads we may have in a configuration.
Let's modify it this way:
- the CID now dedicates 12 bits to the thread ID
- on output we continue to place the TID directly there.
- on input, the value is extracted. If it corresponds to a valid
thread number of the bind_conf, it's used as-is.
- otherwise it's used as a rank within the current bind_conf's
thread mask so that in the end we still get a valid thread ID
for this bind_conf.
The extraction function now requires a bind_conf in order to get the
group and thread mask. It was better to use bind_confs now as the goal
is to make them support multiple listeners sooner or later.
QUIC datagrams are read from a random thread. They are then redispatch
to the connection thread according to the first packet DCID. These
operations are implemented through a special buffer designed to avoid
locking.
Refactor this code with the following changes :
* <rxbuf> type is renamed <quic_receiver_buf>. Its list element is also
renamed to highligh its attach point to a receiver.
* <quic_dgram> and <quic_receiver_buf> definition are moved to
quic_sock-t.h. This helps to reduce the size of quic_conn-t.h.
* <quic_dgram> list elements are renamed to highlight their attach point
into a <quic_receiver_buf> and a <quic_dghdlr>.
This should be backported up to 2.6.
Implement quic_tls_secrets_keys_alloc()/quic_tls_secrets_keys_free() to allocate
the memory for only one direction (RX or TX).
Modify ha_quic_set_encryption_secrets() to call these functions for one of this
direction (or both). So, for now on we can rely on the value of the secret keys
to know if it was derived.
Remove QUIC_FL_TLS_SECRETS_SET flag which is no more useful.
Consequently, the secrets are dumped by the traces only if derived.
Must be backported to 2.6.
This issue was reproduced with -Q picoquic client option to split a big ClientHello
message into two Initial packets and haproxy as server without any knowledged of
any previous ORTT session (restarted after a firt 0RTT session). The ORTT received
packets were removed from their queue when the second Initial packet was parsed,
and the QUIC handshake state never progressed and remained at Initial state.
To avoid such situations, after having treated some Initial packets we always
check if there are ORTT packets to parse and we never remove them from their
queue. This will be done after the hanshake is completed or upon idle timeout
expiration.
Also add more traces to be able to analize the handshake progression.
Tested with ngtcp2 and picoquic
Must be backported to 2.6.
Implement quic_get_ncbuf() to dynamically allocate a new ncbuf to be attached to
any quic_cstream struct which needs such a buffer. Note that there is no quic_cstream
for 0RTT encryption level. quic_free_ncbuf() is added to release the memory
allocated for a non-contiguous buffer.
Modify qc_handle_crypto_frm() to call this function and allocate an ncbuf for
crypto data which are not received in order. The crypto data which are received in
order are not buffered but provide to the TLS stack (calling qc_provide_cdata()).
Modify qc_treat_rx_crypto_frms() which is called after having provided the
in order received crypto data to the TLS stack to provide again the remaining
crypto data which has been buffered, if possible (if they are in order). Each time
buffered CRYPTO data were consumed, we try to release the memory allocated for
the non-contiguous buffer (ncbuf).
Also move rx.crypto.offset quic_enc_level struct member to rx.offset quic_cstream
struct member.
Must be backported to 2.6.
Add new quic_cstream struct definition to implement the CRYPTO data stream.
This is a simplication of the qcs object (QUIC streams) for the CRYPTO data
without any information about the flow control. They are not attached to any
tree, but to a QUIC encryption level, one by encryption level except for
the early data encryption level (for 0RTT). A stream descriptor is also allocated
for each CRYPTO data stream.
Must be backported to 2.6
Retrieve the frontend destination address for a QUIC connection. This
address is retrieve from the first received datagram and then stored in
the associated quic-conn.
This feature relies on IP_PKTINFO or affiliated flags support on the
socket. This flag is set for each QUIC listeners in
sock_inet_bind_receiver(). To retrieve the destination address,
recvfrom() has been replaced by recvmsg() syscall. This operation and
parsing of msghdr structure has been extracted in a wrapper quic_recv().
This change is useful to finalize the implementation of 'dst' sample
fetch. As such, quic_sock_get_dst() has been edited to return local
address from the quic-conn. As a best effort, if local address is not
available due to kernel non-support of IP_PKTINFO, address of the
listener is returned instead.
This should be backported up to 2.6.
Continue on the cleanup of QUIC stack and components.
quic_conn uses internally a ssl_sock_ctx to handle mandatory TLS QUIC
integration. However, this is merely as a convenience, and it is not
equivalent to stackable ssl xprt layer in the context of HTTP1 or 2.
To better emphasize this, ssl_sock_ctx usage in quic_conn has been
removed wherever it is not necessary : namely in functions not related
to TLS. quic_conn struct now contains its own wait_event for tasklet
quic_conn_io_cb().
This should be backported up to 2.6.
xprt_quic module was too large and did not reflect the true architecture
by contrast to the other protocols in haproxy.
Extract code related to XPRT layer and keep it under xprt_quic module.
This code should only contains a simple API to communicate between QUIC
lower layer and connection/MUX.
The vast majority of the code has been moved into a new module named
quic_conn. This module is responsible to the implementation of QUIC
lower layer. Conceptually, it overlaps with TCP kernel implementation
when comparing QUIC and HTTP1/2 stacks of haproxy.
This should be backported up to 2.6.
