selftests/net: mptcp: fix uninitialized variable warnings

Same init_rng() in both tests. The function reads /dev/urandom to
initialize srand(). In case of failure, it falls back onto the
entropy in the uninitialized variable. Not sure if this is on purpose.
But failure reading urandom should be rare, so just fail hard. While
at it, convert to getrandom(). Which man 4 random suggests is simpler
and more robust.

mptcp_inq.c:525:6:
mptcp_connect.c:1131:6:

error: variable 'foo' is used uninitialized
whenever 'if' condition is false
[-Werror,-Wsometimes-uninitialized]

Fixes: 048d19d444be ("mptcp: add basic kselftest for mptcp")
Fixes: b51880568f20 ("selftests: mptcp: add inq test case")
Cc: Florian Westphal <fw@strlen.de>
Signed-off-by: Willem de Bruijn <willemb@google.com>

----

When input is randomized because this is expected to meaningfully
explore edge cases, should we also add
1. logging the random seed to stdout and
2. adding a command line argument to replay from a specific seed
I can do this in net-next, if authors find it useful in this case.
Reviewed-by: Matthieu Baerts <matttbe@kernel.org>

Link: https://lore.kernel.org/r/20231124171645.1011043-5-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: mptcp: remove duplicated entries in usage

mptcp_connect tool was printing some duplicated entries when showing how
to use it: -j -l -r

While at it, I also:

- moved the very few entries that were not sorted,

- added -R that was missing since
commit 8a4b910d005d ("mptcp: selftests: add rcvbuf set option"),

- removed the -u parameter that has been removed in
commit f730b65c9d85 ("selftests: mptcp: try to set mptcp ulp mode in different sk states").

No need to backport this, it is just an internal tool used by our
selftests. The help menu is mainly useful for MPTCP kernel devs.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftest: mptcp: exit from copyfd_io_poll() when receive SIGUSR1

For now, mptcp_connect won't exit after receiving the 'SIGUSR1' signal
if '-r' is set. Fix this by skipping poll and sleep in copyfd_io_poll()
if 'quit' is set.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: mptfo Initiator/Listener

This patch first adds TFO support in mptcp_connect.c.

This can be enabled via a new option: -o MPTFO.

Once enabled, the TCP_FASTOPEN socket option is enabled for the server
side and a sendto() with MSG_FASTOPEN is used instead of a connect() for
the client side.

Note that the first SYN has a limit of bytes it can carry. In other
words, it is allowed to send less data than the provided one. We then
need to track more status info to properly allow the next sendmsg()
starting from the next part of the data to send the rest.

Also in TFO scenarios, we need to completely spool the partially xmitted
buffer -- and account for that -- before starting sendfile/mmap xmit,
otherwise the relevant tests will fail.

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Dmytro Shytyi <dmytro@shytyi.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: mptcp: update and extend fastclose test-cases

After the previous patches, the MPTCP protocol can generate
fast-closes on both ends of the connection. Rework the relevant
test-case to carefully trigger the fast-close code-path on a
single end at the time, while ensuring than a predictable amount
of data is spooled on both ends.

Additionally add another test-cases for the passive socket
fast-close.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: make sendfile selftest work

When the selftest got added, sendfile() on mptcp sockets returned
-EOPNOTSUPP, so running 'mptcp_connect.sh -m sendfile' failed
immediately.

This is no longer the case, but the script fails anyway due to timeout.
Let the receiver know once the sender has sent all data, just like
with '-m mmap' mode.

v2: need to respect cfg_wait too, as pm_userspace.sh relied
on -m sendfile to keep the connection open (Mat Martineau)

Fixes: 048d19d444be ("mptcp: add basic kselftest for mptcp")
Reported-by: Xiumei Mu <xmu@redhat.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: Initialize variables to quiet gcc 12 warnings

In a few MPTCP selftest tools, gcc 12 complains that the 'sock' variable
might be used uninitialized. This is a false positive because the only
code path that could lead to uninitialized access is where getaddrinfo()
fails, but the local xgetaddrinfo() wrapper exits if such a failure
occurs.

Initialize the 'sock' variable anyway to allow the tools to build with
gcc 12.

Fixes: 048d19d444be ("mptcp: add basic kselftest for mptcp")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: mptcp: add disconnect tests

Performs several disconnect/reconnect on the same socket,
ensuring the overall transfer is succesful.

The new test leverages ioctl(SIOCOUTQ) to ensure all the
pending data is acked before disconnecting.

Additionally order alphabetically the test program arguments list
for better maintainability.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: try to set mptcp ulp mode in different sk states

The kernel will crash without
'mptcp: clear 'kern' flag from fallback sockets' change.

Since this doesn't slow down testing in a noticeable way,
run this unconditionally.

The explicit test did not catch this, because the check was done
for tcp socket returned by 'socket(.. IPPROTO_TCP) rather than a
tcp socket returned by accept() on a mptcp listen fd.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: mptcp: add TCP_INQ support

Do checks on the returned inq counter.

Fail on:
1. Huge value (> 1 kbyte, test case files are 1 kb)
2. last hint larger than returned bytes when read was short
3. erronenous indication of EOF.

3) happens when a hint of X bytes reads X-1 on next call
but next recvmsg returns more data (instead of EOF).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

selftests: mptcp: add tproxy test case

No hard dependencies here, just skip if test environ lacks
nft binary or the needed kernel config options.

The test case spawns listener in ns2 but ns1 will connect
to the ip address of ns4.

policy routing + tproxy rule will redirect packets to ns2 instead
of forward.

v3: - update mptcp/config (Mat Martineau)
- more verbose SKIP messages in mptcp_connect.sh

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: more stable simult_flows tests

Currently the simult_flows.sh self-tests are not very stable,
especially when running on slow VMs.

The tests measure runtime for transfers on multiple subflows
and check that the time is near the theoretical maximum.

The current test infra introduces a bit of jitter in test
runtime, due to multiple explicit delays. Additionally the
runtime is measured by the shell script wrapper. On a slow
VM, the script overhead is measurable and subject to relevant
jitter.

One solution to make the test more stable would be adding more
slack to the expected time; that could possibly hide real
regressions. Instead move the measurement inside the command
doing the transfer, and drop most unneeded sleeps.

Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp_connect: add SO_TIMESTAMPNS cmsg support

This extends the existing setsockopt test case to also check for cmsg
timestamps.

mptcp_connect will abort/fail if the setockopt was passed but the
timestamp cmsg isn't present after successful recvmsg().

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: add a test case for MSG_PEEK

Extend mptcp_connect tool with MSG_PEEK support and add a test case in
mptcp_connect.sh that checks the data received from/after recv() with
MSG_PEEK.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Yonglong Li <liyonglong@chinatelecom.cn>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: add packet mark test case

Extend mptcp_connect tool with SO_MARK support (-M <value>) and
add a test case that checks that the packet mark gets copied to all
subflows.

This is done by only allowing packets with either skb->mark 1 or 2
via iptables.

DROP rule packet counter is checked; if its not zero, print an error
message and fail the test case.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: add cfg_do_w for cfg_remove

In some testcases, we need to slow down the transmitting process. This
patch added a new argument named cfg_do_w for cfg_remove to allow the
caller to pass an argument to cfg_remove.

In do_rnd_write, use this cfg_do_w to control the transmitting speed.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: add remove cfg in mptcp_connect

This patch added a new cfg, named cfg_remove in mptcp_connect. This new
cfg_remove is copied from cfg_join. The only difference between them is in
the do_rnd_write function. Here we slow down the transfer process of all
data to let the RM_ADDR suboption can be sent and received completely.
Otherwise the remove address and subflow test cases don't work.

Suggested-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: mptcp: fix typo in mptcp_connect usage

in mptcp_connect, 's' selects IPPROTO_MPTCP / IPPROTO_TCP as the value of
'protocol' in socket(), and 'm' switches between different send / receive
modes. Fix die_usage(): swap 'm' and 's' and add missing 'sendfile' mode.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

mptcp: more stable diag self-tests

During diag self-tests we introduce long wait in the mptcp test
program to give the script enough time to access the sockets
dump.

Such wait is introduced after shutting down one sockets end. Since
commit 43b54c6ee382 ("mptcp: Use full MPTCP-level disconnect state
machine") if both sides shutdown the socket is correctly transitioned
into CLOSED status.

As a side effect some sockets are not dumped via the diag interface,
because the socket state (CLOSED) does not match the default filter, and
this cause self-tests instability.

Address the issue moving the above mentioned wait before shutting
down the socket.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/68
Fixes: df62f2ec3df6 ("selftests/mptcp: add diag interface tests")
Tested-and-acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests/mptcp: add diag interface tests

basic functional test, triggering the msk diag interface
code. Require appropriate iproute2 support, skip elsewhere.

Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

selftests: add test-cases for MPTCP MP_JOIN

Use the pm netlink to configure the creation of several
subflows, and verify that via MIB counters.

Update the mptcp_connect program to allow reliable MP_JOIN
handshake even on small data file

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mptcp: selftests: add rcvbuf set option

allows to run the tests with fixed receive buffer by passing
"-R <value>" to mptcp_connect.sh.

While at it, add a default 10 second poll timeout so the "-t"
becomes optional -- this makes mptcp_connect simpler to use
during manual testing.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

mptcp: fix use-after-free for ipv6

Turns out that when we accept a new subflow, the newly created
inet_sk(tcp_sk)->pinet6 points at the ipv6_pinfo structure of the
listener socket.

This wasn't caught by the selftest because it closes the accepted fd
before the listening one.

adding a close(listenfd) after accept returns is enough:
BUG: KASAN: use-after-free in inet6_getname+0x6ba/0x790
Read of size 1 at addr ffff88810e310866 by task mptcp_connect/2518
Call Trace:
inet6_getname+0x6ba/0x790
__sys_getpeername+0x10b/0x250
__x64_sys_getpeername+0x6f/0xb0

also alter test program to exercise this.

Reported-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

mptcp: add basic kselftest for mptcp

Add mptcp_connect tool:
xmit two files back and forth between two processes, several net
namespaces including some adding delays, losses and reordering.
Wrapper script tests that data was transmitted without corruption.

The "-c" command line option for mptcp_connect.sh is there for debugging:

The script will use tcpdump to create one .pcap file per test case, named
according to the namespaces, protocols, and connect address in use.
For example, the first test case writes the capture to
ns1-ns1-MPTCP-MPTCP-10.0.1.1.pcap.

The stderr output from tcpdump is printed after the test completes to
show tcpdump's "packets dropped by kernel" information.

Also check that userspace can't create MPTCP sockets when mptcp.enabled
sysctl is off.

The "-b" option allows to tune/lower send buffer size.
"-m mmap" can be used to test blocking io. Default is non-blocking
io using read/write/poll.

Will run automatically on "make kselftest".

Note that the default timeout of 45 seconds is used even if there is a
"settings" changing it to 450. 45 seconds should be enough in most cases
but this depends on the machine running the tests.

A fix to correctly read the "settings" file has been proposed upstream
but not applied yet. It is not blocking the execution of these new tests
but it would be nice to have it:

https://patchwork.kernel.org/patch/11204935/

Co-developed-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Co-developed-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Co-developed-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
Signed-off-by: David S. Miller <davem@davemloft.net>