In order to address the absurd polling sequence described in issue #253,
let's make sure we disable receiving on a connection until it's established.
Previously with bottom-top I/Os, we were almost certain that a connection
was ready when the first I/O was confirmed. Now we can enter various
functions, including process_stream(), which will attempt to read
something, will fail, and will then subscribe. But we don't want them
to try to receive if we know the connection didn't complete. The first
prerequisite for this is to mark the connection as not ready for receiving
until it's validated. But we don't want to mark it as not ready for sending
because we know that attempting I/Os later is extremely likely to work
without polling.
Once the connection is confirmed we re-enable recv readiness. In order
for this event to be taken into account, the call to tcp_connect_probe()
was moved earlier, between the attempt to send() and the attempt to recv().
This way if tcp_connect_probe() enables reading, we have a chance to
immediately fall back to this and read the possibly pending data.
Now the trace looks like the following. It's far from being perfect
but we've already saved one recvfrom() and one epollctl():
epoll_wait(3, [], 200, 0) = 0
socket(AF_INET, SOCK_STREAM, IPPROTO_TCP) = 7
fcntl(7, F_SETFL, O_RDONLY|O_NONBLOCK) = 0
setsockopt(7, SOL_TCP, TCP_NODELAY, [1], 4) = 0
connect(7, {sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("127.0.0.1")}, 16) = -1 EINPROGRESS (Operation now in progress)
epoll_ctl(3, EPOLL_CTL_ADD, 7, {EPOLLIN|EPOLLOUT|EPOLLRDHUP, {u32=7, u64=7}}) = 0
epoll_wait(3, [{EPOLLOUT, {u32=7, u64=7}}], 200, 1000) = 1
connect(7, {sa_family=AF_INET, sin_port=htons(8000), sin_addr=inet_addr("127.0.0.1")}, 16) = 0
getsockopt(7, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
sendto(7, "OPTIONS / HTTP/1.0\r\n\r\n", 22, MSG_DONTWAIT|MSG_NOSIGNAL, NULL, 0) = 22
epoll_ctl(3, EPOLL_CTL_MOD, 7, {EPOLLIN|EPOLLRDHUP, {u32=7, u64=7}}) = 0
epoll_wait(3, [{EPOLLIN|EPOLLRDHUP, {u32=7, u64=7}}], 200, 1000) = 1
getsockopt(7, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
getsockopt(7, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
recvfrom(7, "HTTP/1.0 200\r\nContent-length: 0\r\nX-req: size=22, time=0 ms\r\nX-rsp: id=dummy, code=200, cache=1, size=0, time=0 ms (0 real)\r\n\r\n", 16384, 0, NULL, NULL) = 126
close(7) = 0
Commit 8a4ffa0a ("MINOR: send-proxy-v2: sends authority TLV according
to TLV received") is missing parentheses around a variable assignment
used as condition in an if statement, and gcc isn't happy about it.
Since patch "7185b789", the authority TLV in a PROXYv2 header from a
client connection is stored. Authority TLV sends in PROXYv2 should be
taken into account to allow chaining PROXYv2 without droping it.
Save the authority TLV in a PROXYv2 header from the client connection,
if present, and make it available as fc_pp_authority.
The fetch can be used, for example, to set the SNI for a backend TLS
connection.
This commit places calls to sockaddr_alloc() at the places where an address
is needed, and makes sure that the allocation is properly tested. This does
not add too many error paths since connection allocations are already in the
vicinity and share the same error paths. For the two cases where a
clear_addr() was called, instead the address was not allocated.
This pool will be used to allocate storage for source and destination
addresses used in connections. Two functions sockaddr_{alloc,free}()
were added and will have to be used everywhere an address is needed.
These ones are safe for progressive replacement as they check that the
existing pointer is set before replacing it. The pool is not yet used
during allocation nor freeing. Also they operate on pointers to pointers
so they will perform checks and replace values. The free one nulls the
pointer.
This is in preparation for the switch to dynamic address allocation,
let's migrate the code using the old fields to the pointers instead.
Note that no extra check was added for now, the purpose is only to
get the code to use the pointers and still work.
In the proxy protocol message handling we make sure the addresses are
properly allocated before declaring them unset.
It's really confusing to call it a task because it's a tasklet and used
in places where tasks and tasklets are used together. Let's rename it
to tasklet to remove this confusion.
Now that the various handshakes come with their own XPRT, there's no
need for the CONN_FL_SOCK* flags, and the conn_sock_want|stop functions,
so garbage-collect them.
Add a new XPRT that is used when using non-SSL handshakes, such as proxy
protocol or Netscaler, instead of taking care of it in conn_fd_handler().
This XPRT is installed when any of those is used, and it removes itself once
the handshake is done.
This should allow us to remove the distinction between CO_FL_SOCK* and
CO_FL_XPRT*.
As the SSL code may have different needs than the upper layer, ie it may want
to receive when the upper layer wants to right, instead of directly forwarding
the subscribe to the underlying xprt, handle it ourself. The SSL code will
know remember any subscribe call, and wake the tasklet when it is ready
for more I/O.
In conn_fd_handler(), if the fd is ready to send/recv, wake the upper layer
even if we have CO_FL_ERROR, or if CO_FL_XPRT_RD_ENA/CO_FL_XPRT_WR_ENA isn't
set. The only reason we should reach that point is if we had a shutw/shutr,
and the upper layer may want to know about it, and is supposed to handle it
anyway.
Just as is done in previous patch for all handshake handlers,
also stop receiving after a SOCKS4 response was received. This
one escaped the previous cleanup but must be done to keep the
code safe.
Connection handshakes were rarely stacked on top of each other, but the
recent experiments consisting in sending PROXY over SOCKS4 revealed a
number of issues in these lower layers. First, each handler waiting for
data MUST subscribe to recv events with __conn_sock_want_recv() and MUST
unsubscribe from send events using __conn_sock_stop_send() to avoid any
wake-up loop in case a previous sender has set this. Second, each handler
waiting for sending MUST subscribe to send events with __conn_sock_want_send()
and MUST unsubscribe from recv events using __conn_sock_stop_recv() to
avoid any wake-up loop in case some data are available on the connection.
Till now this was done at various random places, and in particular the
cases where the FD was not ready for recv forgot to re-enable reading.
Second, while senders can happily use conn_sock_send() which automatically
handles EINTR, loops, and marks the FD as not ready with fd_cant_send(),
there is no equivalent for recv so receivers facing EAGAIN MUST call
fd_cant_send() to enable polling. It could be argued that implementing
an equivalent conn_sock_recv() function could be useful and more
long-term proof than the current situation.
Third, both types of handlers MUST unsubscribe from their respective
events once they managed to do their job, and none may even play with
__conn_xprt_*(). Here again this was lacking, and one surprizing call
to __conn_xprt_stop_recv() was present in the proxy protocol parser
for TCP6 messages!
Thanks to Alexander Liu for his help on this issue.
This patch must be backported to 1.9 and possibly some older versions,
though the SOCKS parts should be dropped.
Have "socks4" and "check-via-socks4" server keyword added.
Implement handshake with SOCKS4 proxy server for tcp stream connection.
See issue #82.
I have the "SOCKS: A protocol for TCP proxy across firewalls" doc found
at "https://www.openssh.com/txt/socks4.protocol". Please reference to it.
[wt: for now connecting to the SOCKS4 proxy over unix sockets is not
supported, and mixing IPv4/IPv6 is discouraged; indeed, the control
layer is unique for a connection and will be used both for connecting
and for target address manipulation. As such it may for example report
incorrect destination addresses in logs if the proxy is reached over
IPv6]
We still have quite a number of build macros which are mapped 1:1 to a
USE_something setting in the makefile but which have a different name.
This patch cleans this up by renaming them to use the USE_something
one, allowing to clean up the makefile and make it more obvious when
reading the code what build option needs to be added.
The following renames were done :
ENABLE_POLL -> USE_POLL
ENABLE_EPOLL -> USE_EPOLL
ENABLE_KQUEUE -> USE_KQUEUE
ENABLE_EVPORTS -> USE_EVPORTS
TPROXY -> USE_TPROXY
NETFILTER -> USE_NETFILTER
NEED_CRYPT_H -> USE_CRYPT_H
CONFIG_HAP_CRYPT -> USE_LIBCRYPT
CONFIG_HAP_NS -> DUSE_NS
CONFIG_HAP_LINUX_SPLICE -> USE_LINUX_SPLICE
CONFIG_HAP_LINUX_TPROXY -> USE_LINUX_TPROXY
CONFIG_HAP_LINUX_VSYSCALL -> USE_LINUX_VSYSCALL
It is not legal to subscribe if we're already subscribed, or to unsubscribe
if we did not subscribe, so instead of trying to handle those cases, just
assert that it's ok using the new BUG_ON() macro.
It's always a pain to have to stuff lots of #ifdef USE_OPENSSL around
ssl headers, it even results in some of them appearing in a random order
and multiple times just to benefit form an existing ifdef block. Let's
make these headers safe for inclusion when USE_OPENSSL is not defined,
they now perform the test themselves and do nothing if USE_OPENSSL is
not defined. This allows to remove no less than 8 such ifdef blocks
and make include blocks more readable.
For most of the xprt methods, provide a xprt_ctx. This will be useful later
when we'll want to be able to stack xprts.
The init() method now has to create and provide the said xprt_ctx if needed.
AIX defines ip_v as ip_ff.ip_fv in netinet/ip.h using a macro, and
unfortunately we do have a local variable with such a name and which
uses the same header file. Let's rename the variable to ip_ver to fix
this.
The SUB_CAN_SEND/SUB_CAN_RECV enum values have been confusing a few
times, especially when checking them on reading. After some discussion,
it appears that calling them SUB_RETRY_SEND/SUB_RETRY_RECV more
accurately reflects their purpose since these events may only appear
after a first attempt to perform the I/O operation has failed or was
not completed.
In addition the wait_reason field in struct wait_event which carries
them makes one think that a single reason may happen at once while
it is in fact a set of events. Since the struct is called wait_event
it makes sense that this field is called "events" to indicate it's the
list of events we're subscribed to.
Last, the values for SUB_RETRY_RECV/SEND were swapped so that value
1 corresponds to recv and 2 to send, as is done almost everywhere else
in the code an in the shutdown() call.
This adds the sample fetch bc_http_major. It returns the backend connection's HTTP
version encoding, which may be 1 for HTTP/0.9 to HTTP/1.1 or 2 for HTTP/2.0. It is
based on the on-wire encoding, and not the version present in the request header.
This commit replaces the explicit pool creation that are made in
constructors with a pool registration. Not only this simplifies the
pools declaration (it can be done on a single line after the head is
declared), but it also removes references to pools from within
constructors. The only remaining create_pool() calls are those
performed in init functions after the config is parsed, so there
is no more user of potentially uninitialized pool now.
It has been the opportunity to remove no less than 12 constructors
and 6 init functions.
This switches explicit calls to various trivial registration methods for
keywords, muxes or protocols from constructors to INITCALL1 at stage
STG_REGISTER. All these calls have in common to consume a single pointer
and return void. Doing this removes 26 constructors. The following calls
were addressed :
- acl_register_keywords
- bind_register_keywords
- cfg_register_keywords
- cli_register_kw
- flt_register_keywords
- http_req_keywords_register
- http_res_keywords_register
- protocol_register
- register_mux_proto
- sample_register_convs
- sample_register_fetches
- srv_register_keywords
- tcp_req_conn_keywords_register
- tcp_req_cont_keywords_register
- tcp_req_sess_keywords_register
- tcp_res_cont_keywords_register
- flt_register_keywords
Avoid using conn_xprt_want_send/recv, and totally nuke cs_want_send/recv,
from the upper layers. The polling is now directly handled by the connection
layer, it is activated on subscribe(), and unactivated once we got the event
and we woke the related task.
When subscribing, we don't need to provide a list element, only the h2 mux
needs it. So instead, Add a list element to struct h2s, and use it when a
list is needed.
This forces us to use the unsubscribe method, since we can't just unsubscribe
by using LIST_DEL anymore.
This patch is larger than it should be because it includes some renaming.
As we don't know how subscriptions are handled, we can't just assume we can
use LIST_DEL() to unsubscribe, so introduce a new method to mux and connections
to do so.
found by coverity.
[wt: this bug was introduced by commit 404d978 ("MINOR: add ALPN
information to send-proxy-v2"). It might be triggered by a health
check on a server using ppv2 or by an applet making use of such a
server, if at all configurable].
This needs to be backported to 1.8.
Instead of having our wake() method called each time a fd event happens,
just subscribe to recv/send events, and get our tasklet called when that
happens. If any recv/send was possible, the equivalent of what h2_wake_cb()
will be done.
Remove the recv() method from mux and conn_stream.
The goal is to always receive from the upper layers, instead of waiting
for the connection later. For now, recv() is still called from the wake()
method, but that should change soon.
For struct connection, struct conn_stream, and for the h2 mux, add 2 new
lists, one that handles waiters for recv, and one that handles waiters for
recv and send. That way we can ask to subscribe for either recv or send.
Resetting the polling flags at the end of conn_fd_handler() shouldn't be
needed anymore, and it will create problem when we won't handle send/recv
from conn_fd_handler() anymore.
This patch improves the previous fix by implementing the socket draining
code directly in conn_sock_drain() so that it always applies regardless
of the protocol's family. Thus it gets rid of tcp_drain().
Cyril Bonté discovered that the proxy protocol randomly fails since
commit 843b7cb ("MEDIUM: chunks: make the chunk struct's fields match
the buffer struct"). This is because we used to store recv()'s return
code into trash.data which is now unsigned, so it never compares as
negative against 0. Let's clean this up and test the result itself
without storing it first.
No backport is needed.
Multiplexers are not necessarily associated to an ALPN. ALPN is a TLS extension,
so it is not always defined or used. Instead, we now rather speak of
multiplexer's protocols. So in this patch, there are no significative changes,
some structures and functions are just renamed.
This function is generic and is able to automatically transfer data from a
buffer to the conn_stream's tx buffer. It does this automatically if the mux
doesn't define another snd_buf() function.
It cannot yet be used as-is with the conn_stream's txbuf without risking to
lose data on close since conn_streams need to be orphaned for this.
http-request set-src possibly creates a situation where src and dst
are from different address families. Convert both addresses to IPv6
to avoid a PROXY UNKNOWN.
This patch should be backported to haproxy 1.8.
This function is generic and is able to automatically transfer data
from a conn_stream's rx buffer to the destination buffer. It does this
automatically if the mux doesn't define another rcv_buf() function.
Totally nuke the "send" method, instead, the upper layer decides when it's
time to send data, and if it's not possible, uses the new subscribe() method
to be called when it can send data again.
Add a new "subscribe" method for connection, conn_stream and mux, so that
upper layer can subscribe to them, to be called when the event happens.
Right now, the only event implemented is "SUB_CAN_SEND", where the upper
layer can register to be called back when it is possible to send data.
The connection and conn_stream got a new "send_wait_list" entry, which
required to move a few struct members around to maintain an efficient
cache alignment (and actually this slightly improved performance).
Now all the code used to manipulate chunks uses a struct buffer instead.
The functions are still called "chunk*", and some of them will progressively
move to the generic buffer handling code as they are cleaned up.
Chunks are only a subset of a buffer (a non-wrapping version with no head
offset). Despite this we still carry a lot of duplicated code between
buffers and chunks. Replacing chunks with buffers would significantly
reduce the maintenance efforts. This first patch renames the chunk's
fields to match the name and types used by struct buffers, with the goal
of isolating the code changes from the declaration changes.
Most of the changes were made with spatch using this coccinelle script :
@rule_d1@
typedef chunk;
struct chunk chunk;
@@
- chunk.str
+ chunk.area
@rule_d2@
typedef chunk;
struct chunk chunk;
@@
- chunk.len
+ chunk.data
@rule_i1@
typedef chunk;
struct chunk *chunk;
@@
- chunk->str
+ chunk->area
@rule_i2@
typedef chunk;
struct chunk *chunk;
@@
- chunk->len
+ chunk->data
Some minor updates to 3 http functions had to be performed to take size_t
ints instead of ints in order to match the unsigned length here.
This patch add option crc32c (PP2_TYPE_CRC32C) to proxy protocol v2.
It compute the checksum of proxy protocol v2 header as describe in
"doc/proxy-protocol.txt".
This patch implement proxy protocol v2 options related to crypto information:
ssl-cipher (PP2_SUBTYPE_SSL_CIPHER), cert-sig (PP2_SUBTYPE_SSL_SIG_ALG) and
cert-key (PP2_SUBTYPE_SSL_KEY_ALG).