netpfil tests: make the pls tests more robust

Give them more time to hit the expected loss numbers.
We see occasional failures during CI runs. This makes that less likely.

MFC after: 1 week
Sponsored by: Rubicon Communications, LLC ("Netgate")

netpfil tests: disable ICMPv6 rate limiting in the test jail

The dummynet test uses flood ping as source of traffic, so the rate
limiting of ICMP replies broke the test.

Fixes: 32aeee8ce7e72738fff236ccd5629d55035458f8

dummynet: add simple gilbert-elliott channel model

Have a simple Gilbert-Elliott channel model in
dummynet to mimick correlated loss behavior of
realistic environments. This allows simpler testing
of burst-loss environments.

Reviewed By: tuexen, kp, pauamma_gundo.com, #manpages
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D42980

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

dummynet tests: attempt to provoke wf2q+ use-after-free

Attempt to provoke known use-after-free issues with WF2Q+.

Sponsored by: Rubicon Communications, LLC ("Netgate")

pf: Fix tests broken by enabling inet-local filtering

Summary:
Three of the pf dummynet tests were using filter rules which matched
both the intended epair interface as well as lo0 which now receives
PFIL_OUT events for messages delivered to the local network stack (if
enabled). This commit changes the rules to match only for the expected
epair interface.

PR: 268717
Reviewed-by: kp
MFC-after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D40393

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

netpfil tests: add dummynet fq_codel test case

fq_codel was broken due to a missing m_rcvif_serialize() in the enqueue
path.
Add a simple test case to ensure it at least passes traffic.

Sponsored by: Rubicon Communications, LLC ("Netgate")

Temporarily skip flaky test case: sys.netpfil.common.dummynet.ipfw_queue

PR: 264805
Sponsored by: The FreeBSD Foundation

netpfil tests: test removing interfaces with pending dummynet packets

Dummynet queues packets with an associated struct ifnet pointer. Ensure
that things do not explode if that interface goes away with packets
still in the queue.

Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D33065

netpfil tests: dummynet+NAT test for pf

Ensure that NAT still works as expected when combined with dummynet.

MFC after: 3 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D32666

netpfil tests: extend dummynet tests to pf

Now that pf can also use dummynet we should extend the existing dummynet
tests to also test it when used with pf.

Reviewed by: donner
MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D31905

netpfil tests: IPv6 dummynet queue test

Same as the v4 test, but with IPv6.

MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D31789

netpfil tests: dummynet queue test

Test prioritisation and dummynet queues.
We need to give the pipe sufficient bandwidth for dummynet to work.
Given that we can't rely on the TCP connection failing alltogether, but
we can measure the effect of dummynet by imposing a time limit on a
larger data transfer.

If TCP is prioritised it'll get most of the pipe bandwidth and easily
manage to transfer the data in 3 seconds or less. When not prioritised
this will not succeed.

MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D31788

dummynet tests: pipe test for IPv6

MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D31787

netpfil tests: Basic dummynet pipe test

Test dummynet pipes (i.e. bandwidth limitation) with ipfw. This is put
in the common tests because we hope to add dummynet support to pf in the
near future.

MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D30380