git: 1735d66a9c5b - main - pf tests: verify checksum offload handling

The branch main has been updated by kp:

URL: https://cgit.FreeBSD.org/src/commit/?id=1735d66a9c5b08b59a0323d3825d2e7dacd13064

commit 1735d66a9c5b08b59a0323d3825d2e7dacd13064
Author:     Kristof Provost <kp@FreeBSD.org>
AuthorDate: 2025-10-10 15:43:28 +0000
Commit:     Kristof Provost <kp@FreeBSD.org>
CommitDate: 2025-10-11 11:24:25 +0000

    pf tests: verify checksum offload handling
    
    Disable epair's checksum offload on one interface in a nat test, to ensure
    that pf does the right thing in scenarios where one interface offloads checksum
    handling and one does not.
    
    We trust the TCP (or ICMP) checksum verification code to drop the packet if pf
    does it wrong, which will cause the test case to fail.
    
    Suggested by:   tuexen
    Sponsored by:   Rubicon Communications, LLC ("Netgate")
---
 tests/sys/netpfil/pf/nat.sh | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tests/sys/netpfil/pf/nat.sh b/tests/sys/netpfil/pf/nat.sh
index 63658164c1fe..1ef87cee3598 100644
--- a/tests/sys/netpfil/pf/nat.sh
+++ b/tests/sys/netpfil/pf/nat.sh
@@ -55,6 +55,9 @@ exhaust_body()
 	jexec echo ifconfig ${epair_echo}b 198.51.100.2/24 up
 	jexec echo /usr/sbin/inetd -p ${PWD}/inetd-echo.pid $(atf_get_srcdir)/echo_inetd.conf
 
+	# Disable checksum offload on one of the interfaces to ensure pf handles that
+	jexec nat ifconfig ${epair_nat}a -txcsum
+
 	# Enable pf!
 	jexec nat pfctl -e
 	pft_set_rules nat \