7 files changed, 132 insertions, 2 deletions
diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
index 1dd732855d76..4933d045ab66 100644
--- a/tools/testing/selftests/drivers/net/hw/Makefile
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0+ OR MIT
 
 TEST_PROGS = \
+	csum.py \
 	devlink_port_split.py \
 	ethtool.sh \
 	ethtool_extended_state.sh \
diff --git a/tools/testing/selftests/drivers/net/hw/csum.py b/tools/testing/selftests/drivers/net/hw/csum.py
new file mode 100755
index 000000000000..cb40497faee4
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/csum.py
@@ -0,0 +1,122 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""Run the tools/testing/selftests/net/csum testsuite."""
+
+from os import path
+
+from lib.py import ksft_run, ksft_exit, KsftSkipEx
+from lib.py import EthtoolFamily, NetDrvEpEnv
+from lib.py import bkg, cmd, wait_port_listen
+
+def test_receive(cfg, ipv4=False, extra_args=None):
+    """Test local nic checksum receive. Remote host sends crafted packets."""
+    if not cfg.have_rx_csum:
+        raise KsftSkipEx(f"Test requires rx checksum offload on {cfg.ifname}")
+
+    if ipv4:
+        ip_args = f"-4 -S {cfg.remote_v4} -D {cfg.v4}"
+    else:
+        ip_args = f"-6 -S {cfg.remote_v6} -D {cfg.v6}"
+
+    rx_cmd = f"{cfg.bin_local} -i {cfg.ifname} -n 100 {ip_args} -r 1 -R {extra_args}"
+    tx_cmd = f"{cfg.bin_remote} -i {cfg.ifname} -n 100 {ip_args} -r 1 -T {extra_args}"
+
+    with bkg(rx_cmd, exit_wait=True):
+        wait_port_listen(34000, proto="udp")
+        cmd(tx_cmd, host=cfg.remote)
+
+
+def test_transmit(cfg, ipv4=False, extra_args=None):
+    """Test local nic checksum transmit. Remote host verifies packets."""
+    if (not cfg.have_tx_csum_generic and
+        not (cfg.have_tx_csum_ipv4 and ipv4) and
+        not (cfg.have_tx_csum_ipv6 and not ipv4)):
+        raise KsftSkipEx(f"Test requires tx checksum offload on {cfg.ifname}")
+
+    if ipv4:
+        ip_args = f"-4 -S {cfg.v4} -D {cfg.remote_v4}"
+    else:
+        ip_args = f"-6 -S {cfg.v6} -D {cfg.remote_v6}"
+
+    # Cannot randomize input when calculating zero checksum
+    if extra_args != "-U -Z":
+        extra_args += " -r 1"
+
+    rx_cmd = f"{cfg.bin_remote} -i {cfg.ifname} -L 1 -n 100 {ip_args} -R {extra_args}"
+    tx_cmd = f"{cfg.bin_local} -i {cfg.ifname} -L 1 -n 100 {ip_args} -T {extra_args}"
+
+    with bkg(rx_cmd, host=cfg.remote, exit_wait=True):
+        wait_port_listen(34000, proto="udp", host=cfg.remote)
+        cmd(tx_cmd)
+
+
+def test_builder(name, cfg, ipv4=False, tx=False, extra_args=""):
+    """Construct specific tests from the common template.
+
+       Most tests follow the same basic pattern, differing only in
+       Direction of the test and optional flags passed to csum."""
+    def f(cfg):
+        if ipv4:
+            cfg.require_v4()
+        else:
+            cfg.require_v6()
+
+        if tx:
+            test_transmit(cfg, ipv4, extra_args)
+        else:
+            test_receive(cfg, ipv4, extra_args)
+
+    if ipv4:
+        f.__name__ = "ipv4_" + name
+    else:
+        f.__name__ = "ipv6_" + name
+    return f
+
+
+def check_nic_features(cfg) -> None:
+    """Test whether Tx and Rx checksum offload are enabled.
+
+       If the device under test has either off, then skip the relevant tests."""
+    cfg.have_tx_csum_generic = False
+    cfg.have_tx_csum_ipv4 = False
+    cfg.have_tx_csum_ipv6 = False
+    cfg.have_rx_csum = False
+
+    ethnl = EthtoolFamily()
+    features = ethnl.features_get({"header": {"dev-index": cfg.ifindex}})
+    for f in features["active"]["bits"]["bit"]:
+        if f["name"] == "tx-checksum-ip-generic":
+            cfg.have_tx_csum_generic = True
+        elif f["name"] == "tx-checksum-ipv4":
+            cfg.have_tx_csum_ipv4 = True
+        elif f["name"] == "tx-checksum-ipv6":
+            cfg.have_tx_csum_ipv6 = True
+        elif f["name"] == "rx-checksum":
+            cfg.have_rx_csum = True
+
+
+def main() -> None:
+    with NetDrvEpEnv(__file__, nsim_test=False) as cfg:
+        check_nic_features(cfg)
+
+        cfg.bin_local = path.abspath(path.dirname(__file__) + "/../../../net/lib/csum")
+        cfg.bin_remote = cfg.remote.deploy(cfg.bin_local)
+
+        cases = []
+        for ipv4 in [True, False]:
+            cases.append(test_builder("rx_tcp", cfg, ipv4, False, "-t"))
+            cases.append(test_builder("rx_tcp_invalid", cfg, ipv4, False, "-t -E"))
+
+            cases.append(test_builder("rx_udp", cfg, ipv4, False, ""))
+            cases.append(test_builder("rx_udp_invalid", cfg, ipv4, False, "-E"))
+
+            cases.append(test_builder("tx_udp_csum_offload", cfg, ipv4, True, "-U"))
+            cases.append(test_builder("tx_udp_zero_checksum", cfg, ipv4, True, "-U -Z"))
+
+        ksft_run(cases=cases, args=(cfg, ))
+    ksft_exit()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore
index d996a0ab0765..74ae1068229c 100644
--- a/tools/testing/selftests/net/.gitignore
+++ b/tools/testing/selftests/net/.gitignore
@@ -2,7 +2,6 @@
 bind_bhash
 bind_timewait
 bind_wildcard
-csum
 cmsg_sender
 diag_uid
 fin_ack_lat
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 5befca249452..052c21438dc4 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -81,7 +81,6 @@ TEST_PROGS += test_ingress_egress_chaining.sh
 TEST_GEN_PROGS += so_incoming_cpu
 TEST_PROGS += sctp_vrf.sh
 TEST_GEN_FILES += sctp_hello
-TEST_GEN_FILES += csum
 TEST_GEN_FILES += ip_local_port_range
 TEST_GEN_FILES += bind_wildcard
 TEST_PROGS += test_vxlan_mdb.sh
diff --git a/tools/testing/selftests/net/lib/.gitignore b/tools/testing/selftests/net/lib/.gitignore
new file mode 100644
index 000000000000..1ebc6187f421
--- /dev/null
+++ b/tools/testing/selftests/net/lib/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+csum
diff --git a/tools/testing/selftests/net/lib/Makefile b/tools/testing/selftests/net/lib/Makefile
index 48557e6250dd..82c3264b115e 100644
--- a/tools/testing/selftests/net/lib/Makefile
+++ b/tools/testing/selftests/net/lib/Makefile
@@ -1,8 +1,15 @@
 # SPDX-License-Identifier: GPL-2.0
 
+CFLAGS =  -Wall -Wl,--no-as-needed -O2 -g
+CFLAGS += -I../../../../../usr/include/ $(KHDR_INCLUDES)
+# Additional include paths needed by kselftest.h
+CFLAGS += -I../../
+
 TEST_FILES := ../../../../../Documentation/netlink/specs
 TEST_FILES += ../../../../net/ynl
 
+TEST_GEN_FILES += csum
+
 TEST_INCLUDES := $(wildcard py/*.py)
 
 include ../../lib.mk
diff --git a/tools/testing/selftests/net/csum.c b/tools/testing/selftests/net/lib/csum.c
index b9f3fc3c3426..b9f3fc3c3426 100644
--- a/tools/testing/selftests/net/csum.c
+++ b/tools/testing/selftests/net/lib/csum.c